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An extract, transform, and load software application (ETL) enables companies to move data from one or more data resources, reformat the data, clean it up, and load it into another resource (e.g., one or more databases, such as a data mart or a data warehouse). Typically an ETL application is useful where a company has data about a subject that is being used by different software applications or on different systems and the data is in multiple formats or where data is being migrated from one software application to another and the data structures are different.
For instance, a customer service system may store a customer's data in one way, while an accounting system may store data about the same customer differently. For example, the category “female” might be represented in three different systems as F, female, and 0. An ETL application can recognize that these entries mean the same thing and convert them to a target format which may be one of those three formats or may be something different.
However, conversion errors may occur wherein the data when used provides erroneous results, for example. Due to the large amount of data typically converted in ETL processes; the management of the data is often complex and such errors may be difficult to identify. | {
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1. Field of the Invention
The present invention relates to a positioning mechanism for positioning a palletized device in a processing apparatus.
2. Description of the Prior Art
In subjecting a device mounted on a pallet and transported by a conveyor for sequentially processing by different processing apparatuses installed at different processing stations, one previously proposed loading method transfers only the device from the pallet to the processing apparatus and positions the device on the processing apparatus. Another loading method transfers the pallet holding the device to the processing apparatus under the conditions wherein the pallet can be accurately positioned on the processing apparatus and the device is positioned accurately on the pallet. The former loading method requires the transfer of the device from the pallet to the processing apparatus and then from the processing apparatus to the pallet, at each processing station. This of course increases processing time. The latter loading method is difficult to implement because the error in positioning the device on the pallet and in positioning the pallet on the processing apparatus is far greater than the processing error incurred during the actual processing of the device.
In some cases, data representing the qualitative condition of adjustment of the device on the processing apparatus needs to be recorded, or the data of adjustment of the device in the preceding processes needs to be used. In such cases, adjustment data of the device needs to be written down or stored on a recording medium by an information recording apparatus, and preparatory work and determination of conditions for the adjustment of the device then needs to be carried out. | {
"pile_set_name": "USPTO Backgrounds"
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Laser incited thermonuclear fusion reactions have been produced in practice for some time in laser fusion reactor systems yielding significant neutron radiation. These systems basically present fusion fuel pellets in a central reactor chamber and focus a laser beam thereon to explode the pellets one at a time.
It has been proposed to introduce a gaseous compound such as CO.sub.2 into the central chamber for dissociation into desired part CO by the energy from a D-T reaction. Output cooling and quenching of the dissociated elements or compounds by rapid expansion of the volume of gas leaving a fusion chamber has been proposed by Theodor Teichmann in the copending application Ser. No. 414,367 filed Nov. 9, 1973, for example. However, these techniques rely upon the reaction pressure waves directly to carry the product gases out of a fixed volume chamber through a diffusing funnel for cooling upon exit from the chamber.
Additionally, it has been proposed that pressure and rarefaction waves of the pellet explosion itself be used to actuate inlet and discharge valve of the central chamber.
However, it has not heretofore been proposed that the central chamber itself be expandable to more quickly cool and quench the residue gases by rapid expansion of chamber volume or to provide longer life of the central fusion chamber. Neither has it been proposed heretofore that a fusion reaction be used with individual pellet fuel injections to power D-T reaction explosions within a central chamber in the form of a cylinder having a reciprocating piston movable therein and the individual explosions timed to operate in a manner analogous to an internal combustion engine. | {
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Traditional light sources include incandescent, high-intensity discharge (HID), and compact-fluorescent (CFL) light sources, all of which emit light in all directions (i.e., non-directional light beam). To direct the non-directional light beam down from and out of a recessed fixture, lighting manufacturers have traditionally designed reflectors using a parabolic shape, which is intended to focus the non-directional light beam toward an illuminated target (e.g., a floor or wall surface). Rapid advancements in light-emitting diode (“LED”) technology have caused manufacturers to replace the traditional light sources with LED light sources, which are inherently directional light sources. The manufacturers have continued using traditional reflectors (e.g., parabolic-shaped reflectors) to minimize glare; however, LED light sources are inherently less diffuse emitters than these traditional light sources resulting in additional lighting designs concerns. For example, the combination of LED light sources with a traditional reflector may produce a light beam with a light pattern having a harsh edge between a center beam light area and a peripheral light area (surrounding the center beam light area) of the light beam, which is aesthetically unappealing in spot or narrow flood light applications. | {
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The present invention relates to the manipulation and display of data. More particularly, the present invention allows the display of a particular set of data on a variety of different devices having different display types.
Various types of devices are able to receive web page content. These devices include computer systems (such as desktop systems, laptops, and handheld computers), cellular phones, Personal Digital Assistants (PDAs), and other computing devices. These different devices may have different types of displays for displaying data (e.g., different display sizes, different aspect ratios, and different display resolutions). Furthermore, certain devices may have color displays while other devices have a monochrome or gray-scale display. Certain device displays are capable of displaying only text characters while other device displays can display text characters as well as pictures or other graphical information.
Different types of devices receive web page content at different speeds depending on the bandwidth and traffic volume of the communication link between the device and the data source. Thus, the time required to transmit similar web page content is likely to vary from one type of device to another. Users of devices having a slow communication link (caused by reduced bandwidth or increased traffic volume) may want to receive an abbreviated version of the web page content, thereby reducing the time required to transmit the data across the communication link.
Web content developers may want to create web pages that can be received and rendered by multiple types of devices having different types of displays. One solution that supports multiple devices and multiple display types includes annotating each individual web page with information that will allow the web page to be rendered by different types of devices having different types of displays. Separate annotations are required for each type of device and/or each type of display to be supported by the web page. This solution is tedious and time-consuming due to the large number of device types and display types. Further, if new devices or new display types are developed in the future, the web content may require modification to support these new devices or display types.
Another solution that supports multiple devices and/or display types includes creating a separate web page for each type of device and display type that the web content developer desires to support. This solution is also tedious and time-consuming, and requires the creation of additional web pages in the future if new devices or display types are released. This solution also increases the storage space requirements due to the creation of multiple versions of the same web page content.
The system and method described herein addresses these limitations by applying an adaptive layout process to a layout template.
The systems and methods described herein allow a set of data to be formatted for different devices having different types of displays. Using these systems and methods, the content developer is able to create their data content once and have the data content adapted to a variety of different devices and device displays. Once generated, device-specific templates are cached to reduce the processing resources required to display different sets of data on the same type of device.
A particular embodiment retrieves a first template associated with data identified in a data request. A second template is generated using the first template and a device description, which is associated with a device generating the data request.
In one embodiment, the first template is device independent and the second template is associated with the specific device generating the data request and the first template.
In a described embodiment, the second template defines a data presentation format for displaying the requested data on the device generating the data request.
In a particular embodiment, the second template is stored in a cache.
A particular embodiment also retrieves the requested data from a data source and generates formatted data based on the second template and the requested data. The formatted data is then transmitted to the device generating the data request. | {
"pile_set_name": "USPTO Backgrounds"
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Theft of services and goods has increased with the use of telephone access cards to credit telephone calls and the use of credit and other cards to obtain access by phone to personal accounts and to order goods. Unscrupulous observers, to obtain unauthorized access to phone services and credit accounts, will memorize card and PIN numbers while they are being entered either verbally through the mouthpiece of a phone or by keying them in with touchtone phone keys.
One way of avoiding exposure of card and PIN numbers is to use a portable autodialer. A portable autodialer can be a credit card sized device that can be kept in a wallet or pocketbook. They generate audible dial tone multifrequency (DTMF) signals for telephone and card numbers stored in the card for introduction into the mouthpiece of a telephone. There has been increased interest in autodialers with the increased use of telephone access cards. A standard telephone number has seven digits. A long distance telephone number has up to eleven digits. International dialing may require fourteen digits to access an overseas phone. Furthermore, a telephone access or credit card may have fourteen to sixteen digits. It is quite easy to miskey one of the many numbers that are required to be entered necessitating reentry of a long string of numbers.
The use of an autodialer eliminates the need for keying in large strings of numbers into a phone. The card and telephone numbers are stored in the autodialer. Just a few keystrokes are needed to activate the autodialer and select the correct telephone number. Once the autodialer is activated and the number selected, the card is held against the mouthpiece to enter the information in the form of DTMF tones into the telephone.
U.S. Pat. No. 5,377,263, filed Dec. 29, 1992 and entitled "Telephone Dialer Card" and U.S. Pat. No. 5,343,519, filed Sep. 7, 1993 and entitled "Autodialer with Pin Feature" disclose autodialers that transmit PIN numbers along with telephone access and credit card numbers. In both of these patents, the autodialers contain preprogrammed PIN numbers which are transmitted upon appropriate activation of the card. While such an arrangement prevents the previously mentioned unscrupulous observer from overhearing or seeing the numbers being entered, loss or misappropriation of the card can result in its unauthorized use. Furthermore, storing both card and pin numbers in the same device therefore obviates the intended advantage of having separate card and PIN numbers. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
This invention relates to multichannel audio systems and methods, and more particularly to an apparatus and method for deriving multichannel audio signals from a monaural or stereo audio signal.
2. Description of the Related Art
Monaural sound was the original audio recording and playback method invented by Edison in 1877. This method was subsequently replaced by stereo or two channel recording and playback, which has become the standard audio presentation format. Stereo provided a broader canvas on which to paint an audio experience. Now it has been recognized that audio presentation in more than two channels can provide an even broader canvas for painting audio experiences. The exploitation of multichannel presentation has taken two routes. The most direct and obvious has been to simply provide more record and playback channels directly; the other has been to provide various matrix methods which create multiple channels, usually from a stereo (two channel) recording. The first method requires more recording channels and hence bandwidth or storage capacity. This is generally not available because of intrinsic bandwidth or data rate limitations of existing distribution means. For digital audio representations, data compression methods can reduce the amount of data required to represent audio signals and hence make it more practical, but these methods are incompatible with normal stereo presentation and current hardware and software formats.
Matrix methods are described in Dressler, “Dolby Pro Logic Surround Decoder—Principles of Operation” (http:-//www.dolby.com/ht/ds&pl/whtppr.-html); Waller, Jr., “The Circle Surround® Audio Surround Systems”, Rocktron Corp. White Paper; and in U.S. Pat. Nos. 3,746,792, 3,959,590, 5,319,713 and 5,333,201. While matrix methods are reasonably compatible with existing stereo hardware and software, they compromise the performance of the stereo or multichannel presentations, or both, their multichannel performance is severely limited compared to a true discrete multichannel presentation, and the matrixing is generally uncontrolled. | {
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This invention relates to interactive entertainment network systems, such as interactive television (ITV) systems, and to methods for operating such interactive entertainment network systems.
Movie and television audiences are very familiar with previews, those one to three minute video clips that reveal highlights of upcoming shows. The preview clips, which are known as xe2x80x9ctrailersxe2x80x9d in the film industry, are important promotional tools. They play on viewer emotions to entice viewers to see the program. The trailers are carefully crafted by the studios to present the most compelling sales pitch for watching a program. Given the importance of trailers, it is not uncommon for a studio to allocate a significant portion of the entire program budget to the production of a short trailer.
In the newer, interactive television (ITV) environment, it would be advantageous to provide trailers to attract potential viewers into renting a program over the interactive network. ITV systems have a single computerized control center, known as the xe2x80x9cheadendxe2x80x9d, which interactively communicates with multiple distributed television units located in subscriber homes. The headend provides traditional forms of programming, such as the familiar cable and broadcast programs, as well as newer forms of programming, such as video-on-demand. In the video-on-demand (VOD) mode of operation, a viewer can order video movies directly from his/her own television set. Indeed, in a full interactive entertainment network system like this invention, it is contemplated that a viewer will be able to order xe2x80x9con demandxe2x80x9d movies, video games, television shows, and other video content programs from their home.
Video trailers would be particularly useful for the ITV video-on-demand mode to entice viewers into renting a movie, video game, or TV show. However, there is an unresolved issue with respect to how trailers can be conveniently supplied to selective viewer homes. Present designs of ITV systems anticipate having hundreds to thousands of movies, video games, and TV shows stored at the headend. The trailers for these programs will also be stored at the headend. One approach is to transmit the hundreds to thousands of trailers in sequential order, repeating the transmission each time the full repertoire is exhausted. But, this large volume of unrelated trailers is not very manageable or meaningful to the viewer, and thus, not useful from a practical or marketing standpoint. Viewers might become bored watching multiple trailers in which they have no interest and, as a result, switch out of the VOD mode to another channel.
Movie viewers, in particular, are accustomed to browsing for video movies in video rental stores. Such stores offer hundreds to thousands of videos, but have them grouped according to different categories. For instance, videos are often grouped by kind, such as new releases, oldies, westerns, foreign films, family films, and so forth. Other groupings might be by actor/actress name, alphabetical order of title, or topic. These groupings assist a shopper in locating a section of interest within which the shopper can limit his/her search for a suitable video movie.
It would be nice to provide the convenient organization afforded by a video store in the ITV video-on-demand environment. Unfortunately, unlike a video store which has an abundance of physical floor space to present many different. movies, the ITV system only has the limited space available on a TV screen to present the options. Accordingly, it is one object of this invention to provide an ITV system that organizes video movies according to different categories and provides a manageable set of video trailers about the movies.
Another problem is that once the set of video trailers is provided, the viewer would like to scan the trailers at their own pace, skipping the unappealing ones and perhaps replaying the good ones. In today""s remote control TV world, viewers have become conditioned to quickly scanning television channels, one after another, often staying on a channel for only a few seconds. This practice is known as xe2x80x9cchannel surfingxe2x80x9d. It is another objective of this invention to enable a viewer to xe2x80x9csurfxe2x80x9d through the grouped video trailers at their own rate.
This invention provides an interactive entertainment network system with a video-on-demand (VOD) application that is like having a video store in your own home. Viewers are permitted to select criteria for grouping various video content programs (e.g., movies, games, TV shows, etc.) into manageable sets. Once grouped, preview video trailers for the set of programs are displayed. The VOD application permits the viewer to browse the trailers at their own rate, skipping forward to the next trailer or backward to the previous trailer. If the viewer settles on a particular program, the VOD application allows the user to rent the program immediately from the trailer being displayed on their television set, without returning to a menu or other order screen.
The interactive entertainment network system of this invention has a headend connected to multiple user interface units in individual homes via a distribution network, such as cable, RF, and/or satellite network. The headend provides full length video content programs and associated preview video trailers about the video content programs to the user interface units, which are commonly referred to as xe2x80x9cset-top boxesxe2x80x9d in the ITV arena.
The headend has a continuous media server database which stores the actual video data streams of both the full length video content programs and their associated preview video trailers. The video data streams are stored digitally as individual data files. Unique monikers are assigned to each program and trailer to locate them within the continuous media server database. The headend also has a program information database which maintains program data records pertaining to the video content programs. The program data records contain information about the programs, such as a program ID, title, moniker, cast members, director, rating, length of movie, brief description, and so on.
The program information database also contains information pertaining to Is each preview video trailer, such as its trailer ID and moniker. The program information database correlates the program IDs of the full length video content programs with the trailer IDs of the associated preview video trailers. In one implementation, this correlation is accomplished using a join table which interrelates the program and trailer IDs.
Each user interface unit has a processor and a video-on-demand (VOD) application which executes on that processor. The VOD application enables a user to select a group of programs from among all of the programs stored at the headend based upon a specified criteria, such as new releases, star name, title, customized viewer list, or any other definable criteria. The criteria is preferably presented as scrollable lists which the viewer can manipulate to select a certain criteria. In an example implementation, two lists can be presented simultaneously: a star list and a title list. The star list is first displayed, and upon selection of a star, a second list of movie titles in which the selected actor appears is displayed. The second list of movies provides an example manageable set of related video programs from which the viewer can choose.
Once a viewer actively selects a particular criteria, the user interface unit transmits a message containing that criteria to the headend over the distribution network. In response to the message, the headend searches the program information database using the criteria as a query to locate video content programs which meet the specified criteria. The search finds the program data records of the criteria-satisfying programs. The program IDs are extracted from the records and used to cross-reference via the join table to corresponding trailer IDs. The headend uses the trailer IDs to access other records which contain the trailer monikers of the preview video trailers for the video content programs that satisfy the viewer criteria.
As a result, the headend selectively groups a manageable set of preview video trailers for transmission to the requesting user interface unit. The headend transmits the program data records, including the program IDs and monikers and the trailer IDs and monikers. The headend also begins transmitting the set of preview video trailers in sequential order for display on the viewer""s television set. The transmission of the trailers can be automatic, or in response to the viewer actuating a xe2x80x9cpreviewxe2x80x9d icon.
The user interface unit has a memory which queues the trailer monikers and IDs in an order that corresponds to the sequential order in which the associated preview video trailers are to be displayed. A preview browse user interface executes on the user interface unit as part of the VOD application to facilitate display of the preview video trailers.
The preview browse user interface has actuatable control icon buttons which enable a user to skip from a presently displayed preview video trailer to another preview video trailer. In one implementation, the preview browse user interface has next/previous control buttons which enable a user to skip from a presently displayed preview video trailer to a next or previous preview video trailer. Upon actuation, a processor resident at the user interface unit sends to the headend a trailer moniker that is next or previous to the trailer moniker of the presently displayed preview video trailer relative to their queue order within the unit""s memory. The headend retrieves the next/previous trailer and begins transmitting it. To the viewer, this change appears nearly instantaneously, with little latency. The viewer therefore feels in control of the review rate, and is able to xe2x80x9csurfxe2x80x9d through the different previews.
The preview browse user interface also has an operable order icon overlaid on the displayed preview video trailer to enable the user to order the video content program that corresponds to the displayed preview video trailer. Upon ordering, the user interface unit sends a message containing the program moniker of the program associated with the displayed preview video trailer to the headend. The headend uses the program moniker to access the continuous media server database and retrieve the full length video content program. The headend transmits the full length video content program to the requesting user interface unit for display on the viewer""s television set. | {
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The casement window referred to in the present description usually comprises a rectangular (sometimes a polygonal, arched or the like) framework consisting of a frame anchored within an opening in a wall and a sash swingably mounted thereon with locking means preventing unintended opening of the sash.
IL Patent 115840 to Arpal Aluminium Ltd. describes an adjustable casement window suitable for use as a blast resistant framework illustrated in FIGS. 1 to 3 which are indicated as Prior Art. A rectangular framework 2 for a windowpane 4 is mounted within an opening in a wall 6. The framework comprises an outer frame 8 typically made of steel and anchored within a corresponding rectangular aperture formed in the wall 6 by a portion 11 cast within the wall and by other suitable anchors (not shown), as known per se.
A jamb frame 12 is mounted within the outer frame 8 and consists of an upper frame head 14, a lower frame sill 16, a side shutting jamb 18 and a side hinging jamb 20.
The framework 2 further comprises a window sash 22, which consists of a profiled top rail 24, a bottom rail 26, a shutting stile 28 and a hinging stile 30. The window sash 22 is pivotally mounted with respect to the jamb frame 12 by means of hinges 32, secured respectively to the hinging jamb 20 and the hinging stile 30. The jamb frame 12 and the window sash 22 are typically made of a light metal such as aluminum.
The profiles of the vertical sash members 28 and 30 and the profiles of the horizontal sash members 24 and 26 are respectively formed with inwardly directed pairs of reinforcing flanges 34 and 36 designed to receive the end portion of the window pane 4. These profiles are also provided with suitable seals 38 and 40 for preventing egress or ingress of air, noxious gases, dust and water. The window sash 22 is lockable within the jamb frame 12 by means of a rotary handle 42 mounted on the shutting stile 28 and activating a locking mechanism as known per se, the constituent parts of which being generally and collectively designated as 44 in FIG. 3.
Locking mechanisms which are in use in the casement windows usually comprise upright (and sometimes also horizontal) sliding carrier members which are activated by a rotary handle and, in turn, displace a number of associated locking elements to bring them into their locked state. A blast-resistant casement window with such a locking system is described, for example, in IL Patent 103168 to Arpal Aluminium Ltd., and is effective against distortion and/or detachment with blasts corresponding to one atmosphere pressure (1 Bar=14.2 PSI). Experiments have shown that the above-described frameworks may appear to be ineffective against blasts creating pressures higher than those mentioned above. It has been noticed, that the described air-tight frameworks loose their properties due to bending deformations which appear in vertical and horizontal sash members when blast pressure is momentarily applied to the window pane. Such deformations may cause unlocking of some locking elements, consequent weakening of the lock and sometimes result in collapsing of the window pane into the interior of the shelter or room. | {
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1. Field of the Invention
The present invention relates to flash memory technology, and more particularly to scalable charge trapping memory technology adaptable for high speed erase and program operations.
2. Description of Related Art
Flash memory is a class of non-volatile integrated circuit memory technology. Traditional flash memory employs floating gate memory cells. As the density increases in memory devices, and the floating gate memory cells get closer and closer together, interference between the charge stored in adjacent floating gates becomes a problem. This interference limits the ability to increase the density of flash memory based on floating gate memory cells. Another type of memory cell used for flash memory can be referred to as a charge trapping flash memory cell, which uses a dielectric charge trapping layer in place of the floating gate. Charge trapping memory cells use dielectric charge trapping material that causes much less cell-to-cell interference than that encountered with floating gate technology, and is expected to be applied for higher density flash memory.
The typical charge trapping memory cell consists of a field effect transistor FET structure having a source and drain separated by a channel, and a gate separated from the channel by a stack of dielectric material including a tunnel dielectric layer, the charge storage layer, and a blocking dielectric layer. According to the early designs referred to as SONOS devices, the source, drain and channel are formed in a silicon substrate (S), the tunnel dielectric layer is formed of silicon oxide (O), the charge storage layer is formed of silicon nitride (N), the blocking dielectric layer is formed a silicon oxide (O), and the gate comprises polysilicon (S). The SONOS device is programmed by electron tunneling using one of a number of well-known biasing technologies, and erased by hole tunneling or electron de-trapping. In order to achieve practical operational speeds for the erase operation, the tunneling dielectric layer must be quite thin (less than 3 nm). However at that thickness, the endurance and charge retention characteristics of the memory cell are poor relative to traditional floating gate technology. On the other hand, the electric field required for the erase operation using thicker tunneling dielectric layers also causes electron injection from the gate through the blocking dielectric layer. This electron injection causes an erase saturation condition in which the charge level in the charge trapping device converges on an equilibrium level. See, U.S. Pat. No. 7,075,828, entitled “Operation Scheme with Charge Balancing Erase for Charge Trapping Non-Volatile Memory”, invented by Lue et al. However, if the erase saturation level is too high, the cell cannot be erased at all, or the threshold margin between the programmed and erased states becomes too small for many applications.
Technology has been investigated to improve the ability of the blocking dielectric layer to reduce electron injection from the gate for the high electric fields needed for erase. See, U.S. Pat. No. 6,912,163, entitled “Memory Device Having High Work Function Gate and Method of Erasing Same,” Invented by Zheng et al., issued 28 Jun. 2005; and U.S. Pat. No. 7,164,603, entitled “Operation Scheme with High Work Function Gate and Charge Balancing for Charge Trapping Non-Volatile Memory”, invented by Shih et al., Shin et al., “A Highly Reliable SONOS-type NAND Flash Memory Cell with Al2O3 or Top Oxide,” IEDM, 2003 (MANOS); and Shin et al., “A Novel NAND-type MONOS Memory using 63 nm Process Technology for a Multi-Gigabit Flash EEPROMs”, IEEE 2005.
Also, technology has been investigated to improve the performance of the tunneling dielectric layer for erase at lower electric fields. See, U.S. Patent Application Publication No. US 2006/0198189 A1, “Non-Volatile Memory Cells, Memory Arrays Including the Same and Method of Operating Cells and Arrays,” Invented by Lue et al., publication date Sep. 7, 2006 (describing a “BE-SONOS device”); Lue et al., “BE-SONOS: A Bandgap Engineered SONOS with Excellent Performance and Reliability”, IEEE, December 2005; Wang et al., “Reliability and Processing Effects of the Bandgap Engineered SONOS (BE-SONOS) Flash Memory,” IEEE, May 2007. See also, U.S. Patent Application Publication No. 2006/0261401 A1, entitled “Novel Low Power Non-Volatile Memory and Gate Stack”, by Bhattacharyya, published 23 Nov. 2006. BE-SONOS devices have a three layer dielectric tunneling structure that, as explained in more detail below, includes a first layer of silicon dioxide, typically less than 1.5 nm thick (called herein the “tunneling layer”), a layer of silicon nitride, typically less than 2.5 nm thick (called herein the “band offset layer”), and a third layer of silicon dioxide, typically less than 3 nm thick (called herein the “isolation layer”). Significant performance improvements have been provided by this 3 layer structure, relative to the single layer tunneling dielectric, and other attempts at engineering the tunneling dielectric, by taking advantage of the complex tunneling behavior during relatively low electric field operating modes in which charge retention is necessary, during relatively high positive electric field operating modes in which charge tunneling to increase the device threshold is required, and during relatively high negative electric field operating modes in which charge tunneling to decrease device threshold is required.
BE-SONOS technology has been proven to provide excellent performance, overcoming many of the erase speed, endurance and charge retention issues of prior art SONOS type memory. While the BE-SONOS structure provides excellent reliability, the erase speed remains limited. So, it is desirable to further improve erase speeds for charge trapping memory cells, without sacrificing endurance and retention, so that speeds approach those possible using floating gate technologies. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates generally to disks and disk drives, and more particularly to methods and apparatus for thermally bonding lubricant to a disk with use of a heat source at an air bearing surface (ABS) of a magnetic head.
2. Description of the Related Art
A write head is typically combined with a magnetoresistive (MR) or giant magnetoresistive (GMR) read head to form a magnetic recording head, certain elements of which are exposed at an air bearing surface (ABS). The write head comprises first and second pole pieces connected at a back gap that is recessed from the ABS. The first and second pole pieces terminate at the ABS where they define first and second pole tips, respectively. An insulation stack, which comprises a plurality of insulation layers, is sandwiched between the first and second pole pieces, and a coil layer is embedded in the insulation stack. A processing circuit is connected to the coil layer for conducting write current through the coil layer which, in turn, induces magnetic write fields in the first and second pole pieces.
A non-magnetic gap layer is sandwiched between the first and second pole tips. Write fields of the first and second pole tips at the ABS xe2x80x9cfringexe2x80x9d across the gap layer. In a magnetic disk drive, a magnetic disk is rotated adjacent to, and a short distance (fly height) from, the ABS so that the write fields magnetize the disk along circular tracks. The written circular tracks then contain information in the form of magnetized segments with fields detectable by the MR or GMR read head.
One or more heads may be employed in a magnetic disk drive for reading and writing information on circular tracks of a rotating disk. A magnetic recording head is mounted on a slider that is carried on a suspension. The suspension is mounted to an actuator which places the magnetic head to locations corresponding to desired tracks. As the disk rotates, an air layer (an xe2x80x9cair bearingxe2x80x9d) is generated between the rotating disk and an air bearing surface (ABS) of the slider. A force of the air bearing against the air bearing surface is opposed by an opposite loading force of the suspension, causing the magnetic head to be suspended a slight distance (i.e. its fly height) from the surface of the disk.
It is generally desirable to minimize the fly height of a magnetic head. With lower fly heights between the magnetic head and the disk, however, there is an increasing rate of intermittent contacts between the head and the disk. This may result in damage to the disk surface. To mitigate these problems, lubricants are often coated on the disk surface during manufacturing. After the disk surface is coated with the lubricant, it is typically heated in an oven to help xe2x80x9cbondxe2x80x9d the lubricant to the disk surface. This bond may be made through physical absorption such that the lubricant attaches to carbon on the disk surface. After this process, a large amount of the lubricant (e.g. close to 100%) may be bonded to the disk surface.
In time, however, some of the lubricant will debond from the disk surface depending on particular environmental conditions such as humidity. The debonding process creates what may be generally referred to as xe2x80x9cmobilexe2x80x9d lubricant. After such debonding, there may be between 20-50% mobile lubricant on the disk surface. Mobile lubricant is indeed mobile and moves across the disk surface, creating differences in lubricant thickness from the inner diameter (ID) to the outer diameter (OD) of the disk. In particular, air shear forces due to disk rotation and interaction with the slider push the mobile lubricant from the ID to the OD, creating a much thicker lubricant at the OD than the ID. Eventually, the excess mobile lubricant may be spun off of the disk surface and become too thin or depleted on the disk surface to be effective.
Thus, although the disk is coated and bonded with lubricant during manufacture to protect it from the intermittent contact with the head, the lubricant may be depleted from the disk surface during operation of the drive. Because of these problems, several types of lubricant reservoir systems have been disclosed as a means for continuously maintaining a lubricant film on the disk during operation. Use of such lubricant reservoirs, however, may provide too much mobile lubricant than needed. If the mobile lubricant becomes too thick on the disk surface, it may cause oscillating write errors or oscillating thermal erasures. If the excess mobile lubricant is spun off the disk surface, the lubricant may be picked up by the slider and there may be an undesirable slider-to-disk bridging.
Accordingly, what are needed are improved methods and apparatus for bonding lubricants to the surfaces of magnetic disks.
A method of bonding lubricant to a surface of a magnetic disk in a disk drive involves providing a heat source at an air bearing surface (ABS) of a magnetic head; causing the heat source to be energized to produce heat; and causing the magnetic head to be moved across a surface portion of a magnetic disk so that lubricant is thermally bonded to the surface portion from the heat provided by the heat source. Preferably, this lubricant bonding mode of operation of the disk drive is performed on a regular or periodic basis. Alternatively, the mode is activated based on a predetermined environmental condition (e.g. temperature or humidity) or an external signal.
In a first embodiment, the heat source is comprised of first and/or second pole pieces of the magnetic head through which an electrical current is passed. In a second embodiment, the heat source is comprised of a separate heating element which is formed on or within the magnetic head. In this second embodiment, the heating element may be the same heating element that is utilized for thermal-assist writing to the magnetic disk. In a third embodiment, heat is generated by reading data from a data block on the disk and writing the data back to the data block in a repetitive fashion. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to resistive thin films, particularly to metal-oxide thin film resistors, and more particularly to Tixe2x80x94Crxe2x80x94Alxe2x80x94O thin film resistors and a process for fabricating same.
The development of metal-oxide materials has been widely pursued in the electronics industry for use as resistive thin films. The use of multiple phases provides a path to change the film resistivity. See C. A. Neugebauer, xe2x80x9cResistivity of Cermet Films Containing Oxides Of Siliconxe2x80x9d, Thin Solid Films, 6 (1970), 443-447. The dependence of sheet resistivity on composition is well established for systems such as Crxe2x80x94Sixe2x80x94O. See. R. Glang et al., xe2x80x9cResistivity and Structure of Crxe2x80x94SiO Cermet Filmsxe2x80x9d, J. Vac. Sci. Technol., 4 (1967), 163-70; A. A. Milgram et al., xe2x80x9cElectrical and Structural Properties of Mixed Chromium and Silicon Monoxide Filmsxe2x80x9d, J. Appl. Phys. 39 (1968), 4219-4224; N. C. Miller et al., xe2x80x9cCo-sputtered Cermet Filmsxe2x80x9d, Solid State Tech. 11 (1968), 28-30; and H. Steemers et al., xe2x80x9cStable Thin Film Resistors For Amorphous Silicon Integrated Circuitsxe2x80x9d, Mat. Res. Soc. Symp. Proc., 118 (1988), 445-449. The conduction mechanism for these cermet materials (materials composed of ceramics and metals) can be considered quantum mechanical. See. J. E. Morris, xe2x80x9cStructure and Electrical Properties of Auxe2x80x94SiO Thin Film Cermetsxe2x80x9d, Thin Solid Films, 11 (1972), 299-311. For low metallic concentrations, the charge transport is proposed to be by electron tunneling between the metallic particles. See B. E. Springett, xe2x80x9cConductivity Of A System Of Metallic Particles Dispersed In An Insulating Mediumxe2x80x9d, J. Appl. Phys., 44 (1973), 2925-2926. In general, conduction may be considered to be by means of an activated charge transport process. For film resistivities greater than 10xe2x88x922 Ohm-cm, the microstructure is usually comprised of a continuous insulating matrix in which metallic particles are dispersed. An increase in metallic content produces a decrease ion sheet resistivity. For the Crxe2x80x94Sixe2x80x94O system, the insulating matrix is based on the oxide phase of SiO2, with Cr, silicides, and monoxides serving as conductors/semiconductors. A general observation by Neugebauer, Supra, suggests that the SiO2 composition alone could be used to determine the cermet film resistivity to within two orders of magnitude irrespective of deposition technique or conditions. Whereas this summation may represent a general trend, it is not an inclusive statement for the resistivity behavior of Crxe2x80x94Sixe2x80x94O cermets. Initial work at the Lawrence Livermore National Laboratory with the Crxe2x80x94Sixe2x80x94O cermet system has shown a widely varying range of resistivities that span more than twelve-orders of magnitude and are often accompanied by a non-linear current-voltage behavior. See A. Jankowski et al., xe2x80x9cResistivity Behavior Of Crxe2x80x94Sixe2x80x94O Thin Filmsxe2x80x9d, Chem. Phys. Nanostructures and Related Non-Equilibrium Materials, ed. E. Ma. et al., The Minerals, Metals and Materials Soc. Proc. (1997), pg. 211-219. In addition, post-deposition vacuum annealing can cause changes in the resistivity by several orders of magnitude rendering unreliable use of the Crxe2x80x94Sixe2x80x94O film as a resistor layer of constant value. Due to the limitations of producing a consistent resistivity from 105 to 108 Ohm-cm for the Crxe2x80x94Sixe2x80x94O system, an alternate material has been sought which would have a well-defined and stable behavior as a resistor layer.
The present invention provides the sought for alternate for the Crxe2x80x94Sixe2x80x94O system, and it has been determined that the system of the present invention has a well-defined and stable behavior as a resistor layer. The Tixe2x80x94Crxe2x80x94Alxe2x80x94O cermet of the present invention is being developed for use as a thin film resistor since its properties in bulk form are favorable and controllable. The Tixe2x80x94Crxe2x80x94Alxe2x80x94O films are radio frequency (rf) sputter deposited to transfer the target composition to the growing cermet film. The films are rf sputter deposited from ceramic targets using a reactive working gas mixture of Ar and O2. The film resistivity can be discretely selected through target composition and the control of the deposition parameters.
It is an object of the present invention to provide metal-oxide resistive thin films which have a well-defined and stable behavior.
A further object of the invention is to provide a metal-oxide thin film which is thermodynamically stable.
A further object of the invention is to provide Tixe2x80x94Crxe2x80x94Alxe2x80x94O thin film resistors.
Another object of the invention is to provide a Tixe2x80x94Crxe2x80x94Alxe2x80x94O cermet which can be effectively utilized as a resistor material.
Another object of the invention is to provide a process for fabricating Tixe2x80x94Crxe2x80x94Alxe2x80x94O thin film resistors.
Another object of the invention is to provide a process for producing Tixe2x80x94Crxe2x80x94Alxe2x80x94O ceramic targets and films by rf sputter deposition from the ceramic targets using a reactive working gas mixture of Ar and O2.
Another object of the invention is to provide a process for fabricating Tixe2x80x94Crxe2x80x94Alxe2x80x94O films wherein the resistivity of the film can be discretely selected through control of the deposition parameters.
Other objects and advantages of the invention will become apparent from the following description and accompanying drawings. The present invention is directed to Tixe2x80x94Crxe2x80x94Alxe2x80x94O cermets which can be utilized as a resistor material, and to a process for fabricating Tixe2x80x94Crxe2x80x94Alxe2x80x94O thin film resistors. The films are rf sputter deposited from ceramic targets using a reactive working gas mixture of Ar and O2, and having, for example, a ceramic powder blend of 2-12% TiO2, 30-40% Al2O3, and 50-65% Cr2O3, with a film composition, for example, of 1-3 at.% Ti, 15-20 at.% Cr, 10-20 at.% Al, and 58-70 at.% O. The films are deposited to a thickness greater than 0.2 xcexcm in order to avoid effects often seen in metalxide films less than 0.1 xcexcm thick. See T. Filutowicz et al., xe2x80x9cThe Effects Of Film Thickness On Certain Properties Of Crxe2x80x94SiO Cermet Thin Filmsxe2x80x9d, Electron Technology. 10 (1977), 117-126; and H. S. Hoffman et al., xe2x80x9cCermet Resistors On Ceramic Substratesxe2x80x9d, IEEE Trans. On Components. Hybrids And Manufacturing Technol., 4 (4) (1981), 387-395. The film resistivity can be discretely selected through control of the target composition and the sputter deposition parameters. The application of Tixe2x80x94Crxe2x80x94Alxe2x80x94O as a thin film resistor has been found to be thermodynamically stable, unlike other metal-oxide material systems. | {
"pile_set_name": "USPTO Backgrounds"
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1. The Field of the Invention
The present invention generally relates to the field of dental treatment materials. More particularly, the invention relates to packaging materials for dental treatment systems that can be used to bleach or otherwise treat a patient's teeth.
2. The Relevant Technology
Virtually all people desire white or whiter teeth. To achieve this goal, people have veneers placed over their teeth or have their teeth chemically bleached. A common bleaching method involves the use of a dental tray that is custom-fitted to a person's teeth and that is therefore comfortable to wear. One type of customized tray is made from a stone cast representative of a person's teeth. Another is customized directly using a person's teeth as a template (e.g., “boil-and-bite” trays).
Non-customized trays and strips that can be placed over a user's teeth have also been used. Non-customized trays are generally provided in multiple sizes that approximate the shapes and sizes of a variety of users' dental arches, while strips can be folded around the dental arch and under the occlusal tooth surfaces so as to cover at least a portion of the tooth surfaces of the dental arch.
A dental bleaching composition is often supplied in a separate container (e.g., a syringe or tube) from which it can be dispensed into the dental tray prior to placing the tray over the person's teeth. Alternatively, some dental bleaching trays and dental bleaching strips are provided pre-filled and/or pre-coated with a dental bleaching composition.
One disadvantage of pre-filled dental trays is that the dental bleaching compositions are typically sealed within packaging containers that are not completely impervious to water and oxygen molecules. A typical example of an existing package includes a foil or other peelable cover sealed over a rigid plastic support layer. Although the foil peelable cover may act as an effective barrier to water molecules, existing rigid plastic support layers are much less effective in preventing diffusion of water molecules therethrough over time. These existing packaging systems allow a small amount of water to be diffused across the plastic barrier, which can cause the bleaching compositions to eventually lose potency, particularly when stored at room temperature.
Typically water diffuses out of the dental treatment composition and across the plastic support layer of the packaging container, resulting in a dried out and ineffective treatment (e.g., bleaching) composition. Loss of water can decrease stability, resulting in decreased bleaching ability over time. In addition, diffusion of oxygen and water can also reduce stability since it is believed that peroxides release oxygen and water upon decomposition, and the ability of released oxygen and water to diffuse out of the package can shift the equilibrium toward increased peroxide decomposition.
Because of these disadvantages, it is recommended that many pre-filled bleaching systems be stored in a refrigerated environment prior to use. Refrigerated storage increases the stability of peroxide bleaching agents, thereby extending the shelf life of the packaged product. Such storage is often impractical, particularly for dental treatment systems intended for over-the-counter sale where refrigerated shelving may not be available practical.
It would be an improvement in the art to provide a pre-filled pre-packaged dental treatment system including a sealed packaging container that is substantially impervious to water molecules in order to thereby improve shelf life of the dental treatment composition (e.g., bleach). | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a camera switchable automatic between and manual exposure control.
2. Description of the Prior Art
In conventional TTL light measuring systems, the brightness of an object is measured by responding to light coming from the object through the camera's objective lens. These systems fall into one of three types, namely an average light measuring system which measures the average intensity of the light passing through the lens, a weighted measuring system which responds mainly to the brightness in the center of the beam from the subject, and a partial light measuring system that measures the brightness only of an important selected portion of the subject.
Each light measuring system has its own advantages and disadvantages. No one can be considered the best. However, various kinds of TTL automatic exposure (AE) control cameras are manufactured. In such cameras, partial photometric systems are not convenient when photographs are taken rapidly. Thus, TTL-AE cameras often use average light measuring or average photometric systems. Such cameras frequently include automatic shutter or aperture controls as well as manual controls and permit free selection of these controls.
In conventional TTL-AE cameras, the exposure is controlled on the basis of the average light measurement even when the camera is operating in the manual mode. However, a photographer may not desire this type of light measuring system in the manual mode.
Moreover, these types of cameras are unable to measure the brightness even when the exposure is mechanically controlled when the voltage of the power source decreases. This makes correct exposure difficult. Normally, the photographer must estimate the needed exposure.
The purpose of the present invention is to eliminate the shortcomings of conventional TTL-AE cameras.
Another purpose of the present invention is to offer an exposure control device so designated that the light measuring circuit is operable with a low voltage even when the circuit does not operate due to the deterioration of the power source apt to take place in the electrically controlled camera in such a manner that all other circuits than the light measuring circuit can be changed over into the mechanical controls.
Further other purposes of the present invention will be disclosed from the explanations to be made below in accordance with embodiments of the present invention. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a current detecting device, a motor controlling system, an image forming apparatus, a sheet conveying device, a robot, and a current detecting method.
2. Description of the Related Art
Currently known image forming apparatuses employ brushless three-phase direct-current (DC) motors in paper conveying mechanisms or the like. A brushless three-phase DC motor operates with three phases, and therefore three current sensors corresponding to the respective phases are needed in principle in detecting current therethrough. It has been known that use of a current detection approach called the “single-shunt approach” enables current detection in the respective phases with one current sensor (a shunt resistor).
Japanese Unexamined Patent Application Publication No. 2011-147306 discloses a control circuit of an electric motor, the control circuit being configured to correct fluctuations in the value of the voltage across a shunt resistor that have been caused by the influence of the power supply voltage, thereby being capable of accurately detecting current that flows through the one shunt resistor.
However, the control circuit of an electric motor disclosed in Japanese Unexamined Patent Application Publication No. 2011-147306 needs a measurement circuit that directly detects the value of the power supply voltage. The control circuit thus has the disadvantages of having a complicated configuration and consequently being expensive to manufacture. | {
"pile_set_name": "USPTO Backgrounds"
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A sender can transfer money to a recipient over the Internet. For example, the sender and recipient can use online banking services. To transfer money, the sender can provide bank information, e.g., account number and routing number, of the recipient to the sender's bank. The bank can process the transfer, e.g., through a wire transfer or the automated clearing house (ACH) financial network. Alternatively, the sender can use a third party money transfer service to transfer money. The third party transfer service can act as a middleman to the transfer. The sender transfers money to the third party transfer service, and the third party transfer service forwards the money to the recipient. To transfer money, the sender uses software, e.g., a web site or mobile application, developed by the third party money transfer service. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to polypeptides found in vertebrate species, which polypeptides are mitogenic growth factors for glial cells, including Schwann cells. The invention is also concerned with processes capable of producing such factors, and the therapeutic application of such factors.
The glial cells of vertebrates constitute the specialized connective tissue of the central and peripheral nervous systems. Important glial cells including Schwann cells which provide metabolic support for neurons and which provide myelin sheathing around the axons of certain peripheral neurons, thereby forming individual nerve fibers. Schwann cells support neurons and provide a sheath effect by forming concentric layers of membrane around adjacent neural axons, twisting as they develop around the axons. These myelin sheaths are a susceptible element of many nerve fibers, and damage to Schwann cells, or failure in growth and development, can be associated with significant demyelination or nerve degeneration characteristic of a number of peripheral nervous system diseases and disorders. In the development of the nervous system, it has become apparent that cells require various factors to regulate their division and growth, and various such factors have been identified in recent years, including some found to have an effect on Schwann cell division or development.
Thus, Brockes et al., inter alia, in J. Neuroscience, 4 (1984) 75-83 describe a protein growth factor present in extracts from bovine brain and pituitary tissue, which was named Glial Growth Factor (GGF). This factor stimulated cultured rat Schwann cells to divide against a background medium containing ten percent fetal calf serum. The factor was also described as having a molecular weight of 31,000 Daltons and as readily dimerizing. In Meth. Enz., 247 (1987), 217-225, Brockes describes a Schwann cell-based assay for GGF.
Brockes et al., supra, also describes a method of purification of GGF to apparent homogeneity. In brief, one large-scale purification method described involves extraction of the lyophilized bovine anterior lobes and chromatography of material obtained thereby using NaCl gradient elution from CM cellulose. Gel filtration is then carried out with an Ultrogel column, followed by elution from a phosphocellulose column, and finally, small-scale SDS gel electrophoresis. Alternatively, the CM-cellulose material was applied directly to a phosphocellulose column, fractions from the column were pooled and purified by preparative native gel electrophoresis, followed by a final SDS gel electrophoresis.
Brockes et al. observe that in previously reported gel filtration experiments (Brockes et al., J. Biol. Chem. 255 (1980) 8374-8377), the major peak of growth factor activity was observed to migrate with a molecular weight of 56,000 Daltons, whereas in the first of the above-described procedures activity was predominantly observed at molecular weight 31,000. It is reported that the GGF dimer is largely removed as a result of the gradient elution from CM-cellulose in this procedure.
Benveniste et al. (PNAS, 82 (1985), 3930-3934) describe a T lymphocyte-derived glial growth promoting factor. This factor, under reducing conditions, exhibits a change in apparent molecular weight on SDS gels.
Kimura et al. (Nature, 348 (1990), 257-260) describe a factor they term Schwannoma-derived growth factor (SDGF) which is obtained from a sciatic nerve sheath tumor. The authors state that SDGF does not stimulate the incorporation of tritium-labelled TdR into cultured Schwann cells under conditions where, in contrast, partially purified pituitary fraction containing GGF is active. SDGF has an apparent molecular weight of between 31,000 and 35,000.
David and Stroobant (J. Cell. Biol., 110 (1990), 1353-1360) describe the screening of a number of candidate mitogens. Rat Schwann cells were used, the chosen candidate substances being examined for their ability to stimulate DNA synthesis in the Schwann cells in the presence of 10% FCS (fetal calf serum), with and without forskolin. One of the factors tested was GGF-carboxymethyl cellulose fraction (GGF-CM), which was mitogenic in the presence of FCS, with and without forskolin. The work revealed that in the presence of forskolin, inter alia, platelet derived growth factor (PDGF) was a potent mitogen for Schwann cells, PDGF having previously been through to have no effect on Schwann cells.
Holmes et al. Science (1992) 256:1205 and Wen et al. Cell (1992) 69:559 demonstrate that DNA sequences which encode proteins binding to a receptor (p185.sup.erbB2) are associated with several human tumors.
The p185.sup.erbB2 protein is a 185 kilodalton membrane spanning protein with tyrosine kinase activity. The protein is encoded by the erbB2 proto-oncogene (Yarden and Ullrich Ann. Rev. Biochem. 57:443 (1988)). The erbB2 gene, also referred to as HER-2 (in human cells) and neu (in rat cells), is closely related to the receptor for epidermal growth factor (EGF). Recent evidence indicates that proteins which interact with (and activate the kinase of) p185.sup.erbB2 induce proliferation in the cells bearing p185.sup.erbB2 (Holmes et al. Science 256:1205 (1992); Dobashi et al. Proc. Natl. Acad. Sci. 88:8582 (1991); Lupu et al. Proc. Natl. Acad. Sci. 89:2287 (1992)). Furthermore, it is evident that the gene encoding p185.sup.erbB2 binding proteins produces a number of variably-sized, differentially-spliced RNA transcripts that give rise to a series of proteins, which are of different lengths and contain some common peptide sequences and some unique peptide sequences. This is supported by the differentially-spliced RNA transcripts recoverable from human breast cancer (MDA-MB-231) (Holmes et al. Science 256:1205 (1992)). Further support derives from the wide size range of proteins which act as (as disclosed herein) ligands for the p185.sup.erbB2 receptor (see below). | {
"pile_set_name": "USPTO Backgrounds"
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1. Related Field
The present invention relates to a paper making machine for producing tissue paper. The invention also relates to a method of producing tissue paper and to an extended nip roll which is suitable for use in the inventive method.
2. Description of Related Art
A paper making machine for the production of tissue paper is known from U.S. Pat. No. 5,393,384. The paper machine shown therein has a belt impermeable to water which runs in a loop through an extended press nip formed by a shoe press and a counter roll. A press felt is conveyed through the press nip. In one embodiment, a shoe press has been placed such that the press shoe is capable of acting on the tissue drying cylinder. It is stated that the drying effect of the shoe press generates a considerably higher degree of drying than a corresponding roll press and that this, in the conjunction with a nonabsorbent belt which avoids remoistening of the web results in considerably increased drying capacities of a press unit.
Another paper making machine for soft paper such as tissue is disclosed in U.S. Pat. No. 6,547,924. The paper making machine shown in that patent also uses a substantially impermeable belt but this belt is a texturing belt which has a web-contacting surface defining a multitude of regularly distributed depressions and surface portions located between the depressions. The belt is used for the purpose of texturing a relief pattern in a fibrous web in order to increase its bulk. The substantially impermeable belt runs in a loop through a press with a shoe press roll and a counter roll and around a transfer roll that forms a transfer nip with a Yankee dryer.
Yet another paper making machine is shown in U.S. Pat. No. 7,811,418. The paper making machine shown in that patent uses a transfer belt that may have depressions and a permeable structuring fabric which is arranged to transfer the wet paper web to a drying cylinder. In embodiments described in that document, a shoe press is used in which the transfer belt passes through a press nip between a shoe press roll and a counter roll.
The above mentioned patents include a large number of components. It is desirable to reduce the number of components used in the machine.
U.S. Pat. No. 4,144,124 discloses a machine for manufacturing paper such a tissue paper. The machine disclosed in that patent comprises a twin-wire former and a press nip between an inner and an outer press roll. The upper or outer press roll is a suction roll which, together with a Yankee cylinder forms a second nip. An endless fabric such as a wire suitable for pattern embossing is may be used and is said to produce impressions in the paper at the press nips. This machine can use uses fewer rolls in the press section since the suction roll is used two nips, one nip with the so called “inner roll” and one nip with the Yankee cylinder.
It is an object of the present invention to provide a paper making machine for tissue paper which has a simple design and few parts and which is capable of producing a tissue paper web that has a high bulk. These and other objects are achieved by means of the present invention as will be explained. | {
"pile_set_name": "USPTO Backgrounds"
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The present application relates to a semiconductor structure and a method of forming the same. More particularly, the present application relates to a semiconductor nanowire field effect transistor with reduced parasitic capacitance and a method of forming the same.
The use of non-planar semiconductor devices such as, for example, FinFETs, trigate and semiconductor nanowire field effect transistors (FETs) is the next step in the evolution of complementary metal oxide semiconductor (CMOS) devices. A semiconductor nanowire with a partially or a totally surrounding gate is one ideal architecture for off-current reduction in sub-45 nm technologies. A gate-all semiconductor nanowire configuration enables to relax channel film thickness requirements for a target leakage control. Stacked semiconductor nanowires yield very high current levels per layout surface area overcoming the current limit imposed by a small width to pitch ratio. Despite providing very high current levels, prior art stacked semiconductor nanowires have a high parasitic capacitance associated therewith. | {
"pile_set_name": "USPTO Backgrounds"
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(a) Technical Field of the Invention
The present invention relates to a safety monitoring mechanism, and in particular, a safety monitoring mechanism of semiconductor wafer fabrication platform, which can instantaneously detect and rectify the abnormalities of the fabrication process at the initial and final stage.
(b) Description of the Prior Art
A plurality of wafer fabrication process integrate into a platform include Precision 5000, Endura, Centura and Producer and are commonly available in Market. The platform of the conventional fabrication process includes a center delivery chamber provided with a plurality of reaction chamber for fabrication processes, and a loading apparatus is provided to the chamber for transferring the wafers between individual chambers. The differences between these platforms include the number and kinds of fabrication, and other related devices.
As shown in FIG. 1, the Centura fabrication platform 1 includes a center delivery chamber 10 having four reaction chamber 11, a cooling chamber 12, an air pressure cleaning chamber 13, and two loading chamber 14. The delivery chamber 10 includes a loading apparatus 15 for transferring wafer between individual chambers 11, and the four reaction chamber 11 includes etching, CVD, high temperature CVD, and physical vapor phase deposition process. The two loading chamber 14 is connected to a small size cleaning room 16 and one side of the small cleaning room 18 is a wafer loading device 17 to provide to-be treated wafer and the wafers via the loading chamber 14 are transferred to the delivery chamber 10.
The fabrication platform utilizes a loading apparatus to carry the wafer and the wafers are transported between individual reaction chambers. However, the loading apparatus generally includes a mechanical arm, and the loading apparatus of the fabrication platform has become out of date and in the course of loading the wafer to the reaction chamber or taking out the wafer from the reaction chamber, impacts may occur and this will damage the wafer. Generally, the tear and wear of the platform will only be noticed after the wafers have been fabricated. Thus, the wafers that fabricated may have defects. | {
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Options for accessing and listening to digital audio in an out-loud setting were severely limited until in 2003, when SONOS, Inc. filed for one of its first patent applications, entitled “Method for Synchronizing Audio Playback between Multiple Networked Devices,” and began offering a media playback system for sale in 2005. The Sonos Wireless HiFi System enables people to experience music from virtually unlimited sources via one or more networked playback devices. Through a software control application installed on a smartphone, tablet, or computer, one can play what he or she wants in any room that has a networked playback device. Additionally, using the controller, for example, different songs can be streamed to each room with a playback device, rooms can be grouped together for synchronous playback, or the same song can be heard in all rooms synchronously.
Given the ever growing interest in digital media, there continues to be a need to develop consumer-accessible technologies to further enhance the listening experience.
The drawings are for the purpose of illustrating example embodiments, but it is understood that the inventions are not limited to the arrangements and instrumentality shown in the drawings. | {
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1. Field of the Invention
The invention relates to sensors for sensing pressure in a fluid flow line. More particularly, the invention relates to a sensor for sensing differential pressure across an orifice plate in a fluid flow line and for sensing gauge pressure upstream or downstream of the orifice plate.
2. Brief Description of the Prior Art
There are many industrial applications which require the measurement of pressures and temperatures in fluid flow lines.
The oil and gas and chemical processing industries, for example, utilize fluid flow line sensors for a variety of reasons. One common utilization of fluid flow line sensors is to determine flow rate, and thus the volume or mass of fluid passing through a flow line.
Often these measurements are used to compute the cost of a fluid such as hydrocarbon gas which is transferred by pipe from a supplier to a purchaser. It is therefore important that the measurements be as accurate as possible.
State-of-the-art fluid flow computers utilize pressure and temperature measurements to determine flow rate. For example, prior art FIG. 1 illustrates pressure/temperature transmitter 2 which is mechanically coupled to a flow line 4 on either side of a orifice plate 6.
A temperature sensor 8 is provided downstream of the orifice plate 6 and is electrically coupled to the transmitter 2 by a cable 10 through an explosion proof boss 12. The transmitter 2 transmits differential pressure, absolute pressure, and process temperature from an electronics package 14 through a cable 20 to another device (not shown). Pressure sensors (not shown) are housed in housing 16.
The orifice plate 6 causes a drop in pressure from the upstream pressure P1 to the downstream pressure P2 so that a differential pressure may be measured. Different state-of-the-art pressure sensors sense pressure in different ways.
Differential pressure is preferably sensed using a piezoresistive silicon membrane where one side of the membrane is exposed to upstream fluid pressure and the other side of the membrane is exposed to downstream fluid pressure.
Prior art FIG. 2 shows an example of a "meter body" 22 which is used for sensing differential pressure. The meter body 22 generally includes a stainless steel diaphragm assembly 24, a sensor header 26, and a sensor cover 28. The diaphragm assembly 24 includes high pressure diaphragm 30, a low pressure diaphragm 32, and a differential pressure diaphragm 34. The high pressure diaphragm 30 is exposed to upstream high pressure P1 and the low pressure diaphragm 32 is exposed to downstream low pressure P2.
A plurality of contiguous cavities 36 between the high pressure diaphragm 30 and the differential pressure diaphragm 34 are filled with an appropriate fluid such as silicon oil via a fill port 38. Similarly, a plurality of contiguous cavities 40 between the low pressure diaphragm 32 and the differential pressure diaphragm 34 are filled with silicon oil via a fill port 42. High pressure silicon oil is conducted from cavities 36 to a location on one end of the diaphragm assembly 24 via a pressure port 44. Low pressure silicon oil is conducted from cavities 40 to another location at the same end of the diaphragm assembly via a pressure port 46. The sensor header 26 and sensor cover 28 are attached to the end of the diaphragm assembly 24 where the ports 44 and 46 terminate.
The sensor header 26 houses a glass tube 48 with a piezoresistive silicon membrane 50 attached to one end. The other end of the tube 48 is coupled to a radial bore 52 which extends to the side surface of the header 26. The sensor cover 26 is dimensioned to provide an annular space 54 between the sensor header 26 and sensor cover 28. The sensor header 26 and sensor cover 28 are coupled to the diaphragm assembly 24 such that the high pressure port 44 is in fluid communication with one side 50a of the membrane 50 and the low pressure port is in fluid communication with the other side 50b of the membrane 50.
It will be appreciated from FIG. 2 that the side 50b is brought into fluid communication with the port 46 via the tube 48, the bore 52, and the annular space 54.
The piezoresistive silicon membrane 50 is essentially a strain gauge. As illustrated in prior art FIGS. 3 and 3A, four electrical resistors 56a-56d are embedded in the silicon membrane 50 to form a Wheatstone bridge.
Those skilled in the art will appreciate that the change in voltage Delta V across two nodes of the bridge shown in FIG. 3A is proportional to the differential pressure dP=P1-P2. As illustrated schematically in FIGS. 3 and 3A, the membrane 50 is rectangular having an overall thickness "T" and a central circular portion of reduced thickness "t". The ratio of T:t is approximately 50:1 and t is approximately 1 mil. The resistors 56a-56d are preferably arranged at the interface between thickness T and thickness t and according to the lattice structure of the silicon in order to provide the most accurate measurements.
According to some prior art methods, the differential pressure together with temperature is useful in calculating flow rate. A prior art pressure sensor utilizing the principles illustrated in FIGS. 2, 3, and 3A is the Honeywell ST3000 Smart Transmitter.
According to other methods, it is necessary or desirable to measure the static pressure of the fluid, either upstream or downstream. A prior art sensor which is capable of measuring both differential pressure and static pressure is the Honeywell SMV3000 Smart Multivariable Transmitter which is illustrated schematically in prior art FIGS. 4 and 4A.
As shown in FIGS. 4 and 4A, a piezoresistive silicon membrane 50' is mounted on the end of a glass tube 48'. The membrane 50' differs from the membrane 50 described above in that it has a second area of reduced thickness t' which overlies a portion of the wall of the tube 48' and which defines a space 58 containing a vacuum. A second strain gauge comprising resistors 60a-60d is arranged around this portion t'. One side 50'c of the membrane at are t' is exposed to upstream high pressure P1 and the other side 50'd is exposed to vacuum.
Those skilled in the art will appreciate that the voltage differential measured by the strain gauge 60a-60d will be proportional to the absolute pressure Plabs. Given the pressure differential dP and the absolute upstream pressure Plabs, the absolute downstream pressure P2abs is known by Plabs-dP.
With these and some other measurements, mass flow rate and other variables can be calculated. U.S. Pat. No. 5,606,513, the complete disclosure of which is hereby incorporated herein by reference, discloses several methods for utilizing the pressure and temperature measurements.
The Honeywell SMV-3000 is compact, efficient, relatively inexpensive, and is capable of measuring differential and absolute pressure in a single assembly. However, it is sometimes desirable to measure static pressure as gauge pressure rather than absolute pressure. One reason why gauge pressure is more desirable than absolute pressure is that it is easier to calibrate sensors using an atmospheric pressure rather than a vacuum as the reference pressure.
The previously incorporated '513 patent discloses an apparatus for measuring differential pressure dP, upstream absolute pressure P1abs, and upstream gauge pressure P1gauge. However, the apparatus requires several assemblies, is complex, mixes capacitive and piezoresistive measurements, and is relatively expensive. | {
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The present invention relates to a method and apparatus for accurately determining an amount of fuel required to transport a vehicle a known distance.
It is well-known that commercially available vehicles are commonly equipped with fuel gauges. The most common type of fuel gauge utilized is a mechanical device which provides a relative measurement of a vehicle""s available fuel. Typically, these devices display the following increments of available fuel: Empty, xc2xc, xc2xd, xc2xe, and Full.
One drawback of such a system of fuel measurement is that one cannot determine with any accuracy the distance one can travel on the relative amount of fuel displayed. This drawback is particularly problematic in the context of delivering vehicles from a manufacturer to a dealer.
When a vehicle is ready for delivery to a dealer, a manufacturer must provide that vehicle with enough fuel to ensure its arrival. If a manufacturer relies exclusively on traditional fuel gauges, the amount of fuel will inevitably be overcompensated. This is because there is no way to accurately assess the actual amount of fuel that is required. Thus, the excess fuel remaining in each vehicle represents a loss to the manufacturer.
Several attempts have been made to address this problem. One such attempt is an automatic fuel gauge which provides an electronic readout of the distance a vehicle can travel based on the amount of fuel in that vehicle""s tank. These devices, however, are generally inaccurate for most fuel levels other than a full tank. At best, therefore, these devices merely provide a rough estimate of the distance a vehicle can travel based on a particular amount of fuel.
Similarly, other devices have attempted to address this problem by providing a fuel gauge which measures the amount of fuel expended by a vehicle. These devices do not, however, provide an indication of how much fuel remains in the vehicle. Consequently, these devices cannot provide an accurate indication of how far a vehicle can travel on the remaining fuel.
A need exists, therefore, for an improved method of determining fuel levels in vehicles.
It is, therefore, an object of the invention to provide a method and apparatus for accurately determining an amount of fuel required to transport a vehicle a known distance.
One aspect of the invention is defined as a method for accurately determining an amount of fuel required to transport a vehicle a known distance comprising the steps of determining the volume of the vehicle""s fuel tank as a function:)n of the height of the tank; determining the distance the vehicle can travel as a function of fuel volume; placing a fuel measurement device into the fuel tank in order to determine the volume of fuel present therein; wherein the fuel measuring device has a plurality of volume and distance indicators labelled thereon, and wherein the volume and distance indicators correspond to the height of the tank; and determining the amount of fuel required by referring to the distance indicators which correspond to the volume of fuel present in the tank.
Another aspect of the invention is defined as an apparatus for accurately determining an amount of fuel required to transport a vehicle a known distance comprising: an elongated measuring device; wherein the elongated measuring device includes a plurality of volume indicators depicting the volume of fuel in the vehicle""s fuel rank as a function of the height of the tank; wherein the fuel measuring device includes a plurality of distance indicators depicting the distance the vehicle can travel as a function of the fuel volume in the vehicle""s fuel tank; wherein the elongated measuring device is adapted to fit into the vehicle""s fuel tank; and wherein the elongated measuring device exhibits a noticeable change in characteristic when submerged in fuel. | {
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While various fittings have been put together heretofore and joined by solder or adjustable fittings, it is believed the new fitting assembly is an advancement in the art and novel over the known fitting assembly art. | {
"pile_set_name": "USPTO Backgrounds"
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A client device, such as a mobile telephone, may include one or more subscriber identity module (SIM), either physical or virtual, which may store information such as an integrated circuit card identifier (ICCID), international mobile subscriber identify (IMSI), authentication keys, local area identity (LAI), operator specific emergency number, short message service center number (SMSC), user phone number, service provider name (SPN), service dialing numbers (SDN), advice-of-charge parameters, value added service (VAS) applications, and mobile network codes (MNC). In addition, a SIM may include SMS messages and contact information.
Client devices with multiple SIMs may be able to access different networks, since each SIM is typically be associated with a different network. Based on time, location, or other factors, communications using each network may have varying performance and cost. While users of a client device may manually switch between multiple SIMs, it may be difficult for a user to determine which SIM should be used to maximize performance and minimize cost. Thus, a desire exists to improve the information made available to a client device such that the user, or the client device itself, may optimally select a SIM for a particular communication. | {
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With the advent of computers and computer software, a number of advancements have been made to help people manage both their working and non-working lives. To help people who are trying to juggle numerous tasks at work, at home, and in between, electronic tasks and calendaring programs have been developed to assist with the often daunting task of maintaining, tracking and remembering all the things that must be accomplished on a daily basis. Unfortunately, most tasks systems are very one-dimensional in that a user must launch a tasks application, open a task entry user interface component, and then manually enter a task. Oftentimes, this process immediately follows or is associated with an activity where the user is caused to decide that a new task is needed. For example, the user may be reading an electronic mail item, the user may be reading or editing a document (for example, a word processing document, a spreadsheet application document, a slide presentation application document, and the like), the user may be browsing an Internet site, the user may be using a social network application site, etc. For example, if the user is editing a document and decides that he/she needs to create a task or reminder to send the edited document to a colleague one week later, the user must move away from the document, launch a task application, enter a desired task and then return to the document being edited. This cumbersome process reduces the utilization and effectiveness of the task application and often leaves the user to avoid the task application altogether and to resort to hand-writing a note on a scrap of paper or “sticky” note.
It is with respect to these and other considerations that the present invention has been made. | {
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1. Field of the Invention
The present invention relates to computer systems, and, in particular, to circuitry for writing data to and reading data from memory devices in computer systems.
2. Description of the Related Art
In a conventional computer system, a host controller provides clock, address, and other control signals for writing data to and reading data from a memory device, such as a random access memory (RAM). Depending on the particular application, there may be relatively stringent requirements related to the timing at which these different signals are applied in parallel to the memory device. For example, system requirements may limit the difference between the earliest and latest arrival times (also referred to as the skew) of these signals to a specified maximum skew value. In addition, there may be a requirement limiting the overall signal propagation delay from the controller to the memory device to a specified maximum delay value.
In the past, a conventional computer system having two or more different memory devices would typically have separate signal buffering and retiming circuitry dedicated to meeting the skew and/or delay requirements for each different memory device. | {
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The invention relates to electrical circuit arrangements and more particularly to electrical signal processing arrangements. One such circuit arrangement to which the invention relates is a circuit arrangement for producing an output representative of the root mean square (RMS) value of an electrical input signal, and another such circuit arrangement to which the invention relates is for multiplying electrical signals together.
Electrical circuit arrangements for producing an output representative of the RMS value of an input signal are known. Such known forms of circuit arrangement may comprise various forms in which a squaring circuit receives an input signal and squares it, an averaging circuit then produces an average signal proportional to the sum of the squared signal, and a square root circuit then takes the square root of the average signal to produce the required RMS output.
Such circuit arrangements often have application in high precision measurements and a disadvantage of known circuit arrangements is that they are susceptible to errors resulting from noise and/or drift.
An object of the invention is an improved electrical circuit arrangement for producing an output signal dependent on the root mean square value of an input signal.
A more specific object of the invention is such a circuit arrangement which is capable of high accuracy by correcting for errors due to noise and/or drift.
A further object of the invention is an improved electrical multiplying circuit which may be used as the squaring circuit in a circuit arrangement for producing the RMS value of an input signal, though it is not limited to such application and may be used in other applications. | {
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Common types of bee-hives include those known as Langstroth-types. These include stacked elements of hive bodies and supers. Frequent readings of both the total weight of the hive and of the individual hive bodies would be of great value to the bee keeper in monotoring the progress in the production of honey and in assisting him to manage and control bee-hive activity. The weight of a honey storage super tells how much honey is stored. The day-to-day change indicates the strength of the "honey flow" and this information permits the keeper to timely add supers or remove them. In preparing the hive for winter, weighing is virtually the only practical means for assuring that stores are sufficient for the entire winter or to determine what corrective or supplemental measures may be necessary.
At present, hives are more or less permanently set upon scales in the apiary. Usually only one hive among many is scale-mounted and the assumption is made that the non-mounted hives are in the same condition indicated on the single scale. It is well known that this is a poor assumption.
A second method involves a two men team, or a man with a tripod and pole using "fish-scales" to actually weigh each hive. This method is expensive and clumsy and doesn't readily show the weight of each hive body.
It is accepted that the bees tend to work each frame in the super fairly symetrically in the direction from front to back and, furthermore, they tend to a lesser degree to work from the center frames to those left and right of center. Secondly, if the edge of a hive body or super is raised to create a gap or a space between the lower edge of that super and the upper edge of the next lowert super and that gap is less than 0.160 inches, the bees will not attempt to crawl through.
It is readily apparent that there is a need in the bee-hive field to provide a small, portable scale that can be used to quickly and efficiently take weighings, as desired, of portions of individual bee-hives and in respect to a large number of individual hives. | {
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Currently, many arithmetic operations in present implementations of microprocessors are sped up by utilizing an on-board floating point (FP) processor, which implements FP mathematics (i.e., mathematics involving operation upon expressions having a significand and an exponent, where the value of each expression is equal to its significand multiplied by 2exponent), typically on very large numbers. These FP processors can include a fused multiply adder to increase the performance of the FP operations.
Fused multiply adders are well known in the art. In a typical fused multiply adder, two operands, for example, A and B, are multiplied together, and added to another operand C, so that the result R=A*B+C or the result R=A*B−C. Generally, in the circuitry, the operands A and B are first multiplied together, while the other operand C is shifted, and then the product of A and B is added to the shifted C. Next, the sum is normalized by a shifting operation., and finally, the shifted sum is rounded.
As in many FP operations, it is frequently required that a result of a FP operation be rounded. IEEE and other industry standards specify different types of rounding processes, for example, round to zero, round to nearest, round to negative infinity, and round to positive infinity. The computation of whether the resulting FP number needs to be rounded and the rounding process itself can significantly undesirably impede the performance and hardware complexity of the fused multiply adder.
The result R is provided in a form that is unincremented or that is incremented, in order to satisfy the rounding requirement. For example, if there were a rounding requirement of either round to zero or round to negative infinity, then the unincremented result R would be output. If there were a rounding requirement of round to positive infinity, then the incremented result R would be output. Further, if the rounding requirement were round to nearest, then either the incremented or unincremented result R would be output.
To more specifically explain the rounding/incrementing process, consider an example of a FP fused multiply adder with rounding capabilities shown in FIG. 1 and generally denoted by reference numeral 5. The fused multiply adder 5 of FIG. 1 is designed to operate upon the significand portions (nonexponent part) of FP numbers. As is well known in the art, the exponent portions of such FP numbers are processed separately from the significand portions, and such processing is not described here for simplicity. As shown in FIG. 1, the fused multiply adder 5 includes a multiplier 11 that receives and multiplies two numbers A, B (for example, 64-bits each). Shifter 12 shifts the operand C by a predetermined amount in order to normalize it with respect to the mathematical product of A and B and to thereby enable it to be appropriately combined with the product of A and B at a later time.
The sum and carry outputs (for example, 128 bits each) of the multiplier 11 and the output of the shifter 12 are input into carry save adder 13, the design and operation of which is well known in the art. The sum and carry data from multiplier 11 are input to the carry, save adder 13 as the addend and augend, respectively. The input from the shifter 12 is considered the carry-in from a less significant stage of the FP fused multiply adder 5. The carry save adder 13 generates a sum output and a carry output. Both the sum and carry outputs are input into a carry propagation adder 14 and a leading bit anticipator 15. The carry propagation adder 14 combines the sum and carry output from the carry save adder 13 to produce a FP number that is input into shifter 16. The design and operation of a carry propagation adder is also well known in the art.
The leading bit anticipator 15 computes a shift number that is equal to the number of significant bits to be shifted out to eliminate the leading zeros in the FP number generated by the carry save adder 13. The leading bit anticipator 15 also computes the shift number in a particular direction. This is done in order to determine the normalization of the sum and carry output of the carry save adder 13, for add, subtract, multiply or divide operations. An example of one of many possible architectures for the leading bit anticipator 15 is described in U.S. Pat. No. 5,798,952 to Miller et al.
The shift number generated by the leading bit anticipator 15 is input into shifter 16. Shifter 16 then performs a shifting operation on the FP number. The FP number is shifted by a number of bits equal to the shift number generated by the leading bit anticipator 15. Shifter 16 performs the function of shifting the FP number to the right or left alternatively as directed by the shift number. This is to eliminate the leading zeros of the FP number (i.e., normalizes the resulting FP number). The resulting normalized FP number is input into incrementor 17, rounding logic 18, and multiplexer (MUX) 19.
The incrementor 17 increments the normalized FP number to provide an incremented normalized FP number. The incrementor 17 inputs the incremented normalized FP number into MUX 19.
The rounding logic 18 determines if the normalized number output from shifter 16 requires rounding and the type based upon the examination of guard, round, and sticky bits associated with the output from shifter 16. The rounding logic 18 directs MUX 19 to select either the unincremented number or the incremented number for ultimate output from the FP fused multiply adder 5.
A major problem with the rounding architecture for a conventional FP fused multiply adder is that until the number resulting from a FP operation is normalized, it is very difficult, if not impossible, to determine whether the normalized result requires rounding. Since the incrementing of a result of a FP operation is performed after the normalization, extra time is needed to complete the FP operation. Furthermore, the incrementor is disadvantageous, as it can add many undesirable gate delays, i.e., at least log2 N gate delays where N is the number of bits. Both of the foregoing significantly compromises the performance of the fused multiply adder 5.
Thus, a heretofore unaddressed need exists in the industry for a way to address the aforementioned deficiencies and inadequacies, particularly, a way to better perform rounding, or incrementing, in a fused multiply adder 5. | {
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The present invention relates to a single crystal of an oxide garnet or, more particularly, to a novel single crystal of an oxide garnet useful as a material of magneto-optical devices such as optical isolators, optical switches and the like exhibiting improved behavior of light absorption at the working wavelengths.
It is an established prior art that magneto-optical devices such as optical isolators and the like are prepared from a single crystal layer of a bismuth-substituted rare earth-iron garnet grown on a substrate single crystal by the liquid-phase epitaxial method. There is an unavoidable problem in this liquid-phase epitaxial method that the garnet single crystal is heavily contaminated with lead or platinum originating in the lead oxide used as a flux of the oxide melt and the platinum-made crucible, respectively. When such a contaminated epitaxial garnet single crystal is used as the magneto-optical element, absorption of light is greatly increased at the working wavelengths of 0.8 .mu.m, 1.3 .mu.m and 1.55 .mu.m to cause an increase in the insertion loss.
A remedial measure for the above mentioned problem is proposed in Preprint for the 11th Conference of Japan Association of Applied Magnetics, November, 1987, 2C-10, page 137, according to which trace amounts of divalent or tetravalent metallic ions, e.g., Ca.sup.2+,Mg.sup.2+ and Ti.sup.4+, are added to the oxide garnet single crystal of this type. This method, however, does not provide a complete solution of the problem because the addition of the above mentioned metallic ions to the melt for the epitaxy necessarily causes changes in the composition of the epitaxially grown layer in the course of the growth so that the uniformity in the performance of the epitaxial garnet layer throughout the thickness can hardly be ensured since the epitaxial layer is usually required to have a thickness as large as 50 .mu.m or larger. | {
"pile_set_name": "USPTO Backgrounds"
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Photoconductive compositions and elements are well known for use in electrophotographic imaging processes. Some of the most useful photoconductive compositions comprise an electron-donating photoconductive material and a sensitizer for the photoconductor. | {
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1. Field of the Invention
This invention relates to a method for fabricating a semiconductor device, and more particularly, to a method for fabricating a semiconductor device by using self-align contact (SAC).
2. Description of the Prior Art
With the advent of Ultra Large Scale Integrated (ULSI) semiconductor devices, the size of the semiconductor device becomes smaller and smaller such that the width of a single semiconductor device has become very small. The manufacture of a semiconductor device usually includes the fabrication of the transistor, the bit line, and the word line, and further includes the contacts. The devices of small area in the semiconductor device with self align contact technology are thus very important for the designer.
The traditional technology employed to fabricate the semiconductor device with the polycide gate using self-align contact often suffers from the rough side-wall after LDD oxidation mainly due to the extruded oxides of polycide. This phenomenon mentioned above frequently results in rough and extruding side-wall which degrades the isolation between polycide gates and self-align contacts.
Taking the method for fabricating a semiconductor device, such as a word line or a transistor, as an example, the transistor-manufacturing method is illustrated as prior art. When the substrate 10 is provided in the manufacturing process, the gate oxide layer 11, the polycrystalline silicon layer 12, and the tungsten silicide layer 13 are subsequently formed on the substrate 10. Next, a TEOS oxide layer 14 is optionally formed on the tungsten silicide layer 13. The TEOS oxide layer 14 can be formed by the CVD (Chemical Vapor Deposition) method. The silicon nitride layer 15 is formed on the TEOS oxide layer 14, and then the photoresist layer 16 is used as a mask when anisotropically etching the silicon nitride layer 15 and the TEOS oxide layer 14. Next, referring to FIG. 1B, photoresist layer 16 is stripped and the polycrystalline silicon layer 12 and the tungsten silicide layer 13 are anisotropically etched to form the multi-layer. The multi-layer above includes the etched polycrystalline silicon layer 12, the etched tungsten silicide layer 13, the etched TEOS oxide layer 14, and the etched silicon nitride layer 15.
Referring to FIG. 1C, the spacer 20 is formed on the side-wall of the foregoing multi-layer to finish the semiconductor device. However, during the subsequent processes, the oxidation process and the self-align technology are employed to proceed with the semiconductor device. The dielectric layer 25, such as an oxide layer, referring to FIG. 1D, formed on the semiconductor device is then etched to form a contact hole. A portion of the substrate 10 is exposed, and then a conductive layer 30 is formed and patterned on the exposed portion of the spacer 20 and the exposed portion of the gate oxide layer 11. The dielectric layer 25 and the subsequent processes are performed to manufacture the semiconductor device.
When the oxidation process is applied to the semiconductor device mentioned above, the polycrystalline silicon generated from the side-wall of the tungsten silicide layer 13 will result in a rough and extruded side-wall which degrades the isolation between polycide gates and self-align contacts. The phenomenon mentioned above results from the portion 35 of the thickness reduced spacer 20. | {
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Human bodies, as well as other organisms and substances, produce electromagnetic radiation in the form of, for example, heat or infrared radiation. In certain circumstances it may be desirable to retain this radiation, such as, for example, applications in which maintaining body heat or food temperature is desired. For example, once a food product is cooked, it may reach a certain temperature; however, this heat is often lost by exposure to cooler temperatures such as ambient air. In another example, a human body may be exposed to cooler temperatures, and infrared radiation may be lost through the epidermis. Retaining this infrared radiation, may have certain beneficial properties including maintaining a particular temperature, evading detection by infrared sensors, insulating pipes and other construction materials to prevent heat transfer, and providing heat to prevent joint stiffness. Known fibers do not completely solve the escape of radiation from a heat-emitting object, without also creating moisture or other undesirable side effects. | {
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Due to the sharp cutoff capability and high cost performance, digital filters are increasingly used in many applications, instead of analog filters. digital filters are of two types, i.e., IIR (infinite impulse response) filter and FIR (finite impulse response) filter. For digital radio, FIR low-pass filters are employed because of their linear operating characteristic for input-output phase relationship. Since the shift registers that comprise a digital filter are the primary source of aliasing, or fold-over distortion noise, they are clocked at twice the symbol rate for oversampling the incoming signal. The clock rate of the shift registers thus determines the maximum operating speed of a digital filter. If higher transmission speed is desired for a system, the clock rate of the digital filters must be increased. However, the operating speed of a digital filter is limited to the maximum operating speed of the integrated circuit components that comprise the shift registers and other constituent parts of the filter.
One approach would be to design a digital filter with two parallel subsystems each being operated respectively on two clock sequences each being out of phase by .pi. radian with respect to the other. However, the hardware cost of the filter is twice as much as the current FIR digital filter. | {
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Multi-mode 850-nm VCSELs based upon the AlGaAs materials system have been the standard optical source for application to glass optical-fiber-based data communication links. However, the implementation of VCSELs for other applications frequently requires different wavelengths and performance attributes than those for which the 850-nm multi-mode VCSELs have been optimized.
As a first example, a very important optically based non-invasive medical-sensor application is oximetry. Pulse oximetry is well-established, and tissue or regional oximetry is an emerging application. Both of these versions of oximetry take advantage of the varying absorption coefficient as a function of wavelength for different types of hemoglobins, (i.e., oxyhemoglobin, reduced hemoglobin, carboxyhemoglobin, or methemoglobin). The sensors rely on the absorption of wavelengths in the regime from about 660 nm to 1000 nm, and as the number of hemoglobin types that are to be analyzed increases, the number of different wavelengths that are required also increases. These applications benefit from the narrow spectral linewidth and the slow spectral shift with temperature of the VCSEL, while wireless implementations benefit from the reduced power consumption of VCSELs as compared to light emitting diodes (LEDs). However, to be commercially viable, VCSEL wavelengths spanning the range from red to near-infrared are required, and in particular, red wavelengths are an important aspect of these systems.
A second example application is plastic optical-fiber links based on poly(methyl methacrylate) (PMMA) fiber materials that have been implemented for sensor and data links in automobiles, and are currently being considered for use in home networks. In some embodiments, PMMA-based fiber has a primary-absorption minimum in the green-wavelength region, and a secondary absorption minimum in the red-wavelength region. Absorption at 850 nm is too high to be practical for typical plastic fiber links having lengths of more than just a few meters.
There is a need for improved laser systems, and in particular, there is a need for VCSELs having improved device characteristics, improved manufacturability, expanded wavelength coverage, improved performance, improved reliability, and improved performance, and additional packaging techniques in order to provide commercially viable devices, products, and systems. | {
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Many electronic systems control on-chip voltages from external power supply sources using linear dropout regulators (LDOs) formed of transistors and capacitors rather than inductors. Such low-dropout regulators serve as direct current (DC) linear voltage regulators that can regulate the output voltage even when the supply voltage is very close to the output voltage.
LDOs have become available for use in on-chip circuitry. Bringing LDOs on-chip has the desirable effect of reducing parts counts, reducing chip I/O (input/output or IO) count, and improving reliability of the electronic system 100. However, on-chip LDOs introduce several undesirable characteristics. Specifically, because these on-chip LDOs use transistors and small capacitors rather than relatively large inductive components and relatively large capacitive components, during operation, these on-chip LDOs introduce undesired voltage transients or ripples at their outputs. When the load on the LDO is small, the voltage swings during rippling can oscillate through overshoots and undershoots—sometimes undershooting to a voltage level well below brownout voltages. As a result, circuitry powered by the LDO may exhibit unwanted behavior (e.g., spontaneously resetting) when the rippling voltage drops below the brownout voltages of the downstream circuit components.
In certain electronic systems, portions of the electronic system 100 including the LDOs can be powered down or placed in a low-power mode during periods when portions of the electronic system 100 are inactive, such as when in a sleep, or dormant, or hibernating mode. Switching between such modes may cause the LDOs to exhibit the unwanted transients described above. Such transients may cause downstream circuitry to receive voltages below their brownout voltages, which in turn can cause such circuitry to fail. Thus, it may be desirable to eliminate or mitigate voltage transients that occur at the outputs of the LDO regulators when changing power modes. | {
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Electrically-driven vehicles using rotating electric machines as drive sources, such as hybrid vehicles and electric cars, are mounted with DC power supplies. For example, International Publication No. WO 2013/157049 discloses a hybrid vehicle including a high-output battery unit having a relatively high output (W) and a high-capacity battery unit having a relatively high capacity (Ah).
In an electric vehicle (EV) drive mode in which a vehicle is driven solely by a rotating electric machine, electric power is supplied mainly from the high-capacity battery unit to the rotating electric machine. When an output request exceeding the maximum output of the high-capacity battery unit is received, electric power is supplied from the high-output battery unit in place of the high-capacity battery unit.
In order to charge these battery units, “external charge”by an external power supply is performed in so-called plug-in hybrid vehicles. Such a vehicle is provided with a connector (charging port) called a “charging inlet” for connecting an external power supply.
The charging inlet may be positioned at a rear side of a vehicle. International Publication No. WO 2013/157049 describes that the high-capacity battery unit and the high-output battery unit are provided in a luggage space at a rear side of the vehicle. By providing all of the charging inlet, the high-capacity battery unit, and the high-output battery unit near to each other at a rear side of the vehicle, wiring resistance in external charge components can be suppressed. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a light emitting apparatus incorporating a semiconductor light emitting device using a nitride semiconductor (e.g., gallium nitride compound semiconductor InxAlyGa1xe2x88x92xxe2x88x92yN, where 0xe2x89xa6x, 0xe2x89xa6y, and x+yxe2x89xa61) and a method for mounting the light emitting device. In particular, the present invention relates to a light emitting apparatus incorporating a nitride semiconductor light emitting device including a substrate which transmits light therethrough and a method for mounting the light emitting device.
2. Description of the Related Art
Typically, a nitride semiconductor light emitting device is produced by depositing a semiconductor multilayer which includes a number of nitride semiconductor layers on an insulative substrate. The semiconductor multilayer is then partially etched into a step like shape. Then a p-type electrode and an n-type electrode are formed on the semiconductor multilayer. The n-type electrode is formed on a lower step of the partially etched semiconductor multilayer. Thus, the height of the n-type electrode differs from that of the p-type electrode. Typically, the n-type electrode is formed at a height which is about 1 xcexcm lower than that of the p-type electrode. One way to emit the light from the nitride semiconductor light emitting device is to include a light transmissive substrate. Conventional mounting methods for electrically connecting such p-type and n-type electrodes formed at different heights to respective electrodes of respective lead frames will be described below.
For example, Japanese Laid-open Patent Publication No. 9-181394 discloses a method in which a nitride semiconductor light emitting device provided with a height difference is mounted on a heat sink that is also provided with a height difference so as to conform with the height difference between the p-type electrode and the n-type, electrode of the light emitting device. FIG. 8 is a schematic diagram illustrating the mounting method. Referring to FIG. 8, a p-type electrode 71 and an n-type electrode 72 are formed on one side of a nitride semiconductor light emitting device 70. A height difference section 700 is provided in a heat sink 73 so as to match with the height difference between the p-type electrode 71 and the n-type electrode 72. The n-type and p-type electrodes 72 and 71 are connected to lead electrodes 75 and 74, respectively, with a conductive material 77.
Japanese Laid-open Patent Publication No. 6-177434 discloses another conventional method for mounting a nitride semiconductor light emitting device, in which the height of an n-type electrode is adjusted to match with that of a p-type electrode. FIG. 9 is a schematic diagram illustrating the mounting method. A thick n-type electrode 80 and a thin p-type electrode 81 are formed on a nitride semiconductor light emitting device 79 so that the surface heights thereof match with each other. The n-type and p-type electrodes 80 and 81 are surrounded by an insulative protective film 82, and connected to lead electrodes 85 and 86 via conductive adhesive layers 83 and 84, respectively.
The first conventional method shown in FIG. 8 has the following problems. In this method, the nitride semiconductor light emitting device 70 needs to be mounted on the heat sink 73 while the p-type electrode 71 and the n-type electrode 72 of the light emitting device 70 are simultaneously placed on (and thus connected to) the lead electrodes 74 and 75 of the heat sink 73, respectively. Therefore, the method requires a very high die bonding accuracy. This causes difficulties during the manufacture of the light emitting device.
The second conventional method shown in FIG. 9 has the following problems. When this method is used with an ordinary light emitting diode or laser, the n-type electrode 80 needs to be as thick as about 1 xcexcm. Such a thick electrode complicates the production process. In stead of making the n-type electrode 80 thicker than the p-type electrode 81, the conductive adhesive layer 83 may be made thicker than the conductive adhesive layer 84 to similarly compensate for the height difference. In such a case, during a die-bonding process for the nitride semiconductor light emitting device, the conductive adhesive material may extend beyond the periphery of the electrode 80 or 81, which may short-circuit the electrodes 80 and 81 with each other. Thus, the production yield may be reduced considerably.
In either one of the conventional methods described above, since the semiconductor layer side is fixed to the heat sink with an adhesive (such as a silver paste and a solder), the semiconductor layer tends to be distorted thereby shortening the lifetime of the nitride semiconductor light emitting device.
Another problem with a conventional light emitting device is that the emission efficiency is decreased because the emitting light is absorbed and scattered by the electrodes formed on the semiconductor layer.
As described above, it has been difficult to provide a method for mounting a nitride semiconductor light emitting device, which improves the emission efficiency and hence the lifetime thereof.
According to one aspect of the present invention, there is provided a light emitting apparatus including: a light emitting device for emitting light; and a first lead frame and a second lead frame on which the light emitting device is mounted. In this apparatus, the light emitting device includes: a substrate which is light transmissive, the substrate defining an output surface; a semiconductor layer formed on the substrate which includes a light emitting layer made of a nitride semiconductor; a first electrode provided lower than a plane running parallel through the light emitting layer with respect to the substrate; and a second electrode provided higher than the plane running parallel through the light emitting layer with respect to the substrate; the first lead frame includes a first lead pad section to which the first electrode is connected; the second lead frame includes a second lead pad section to which the second electrode is connected, at least one of the first and second lead frames includes a die pad section on which the substrate is mounted; and the die pad section does not substantially cover the first output surface.
In one embodiment of the present invention, the light emitting device includes a reflective layer which reflects the light generated in the light emitting layer toward the substrate.
In another embodiment of the present invention, the reflective layer is formed between the light emitting layer and the second electrode.
In still another embodiment of the present invention, the reflective layer is formed to surround the light emitting device.
In still another embodiment of the present invention, the semiconductor layer includes at least a pair of cladding layers, the light emitting layer being made of a gallium nitride type compound semiconductor and being formed between the cladding layers; the reflective layer is a multilayer film including at least two different types of layers which are alternately deposited on one another; and the at least two different types of layers include a first layer made of a nitride semiconductor and having a refractive index of n, and a thickness of xcex/(4xc2x7n1) (where xcex denotes an emission wavelength of the light emitting device), and a second layer made of a nitride semiconductor with a refractive index of n2 and having a thickness of xcex/4xc2x7n2.
In still another embodiment of the present invention, the semiconductor layer includes at least a pair of cladding layers, the light emitting layer being made of a gallium nitride type compound semiconductor and being formed between the cladding layers; the second electrode has a property of transmitting light with a specific wavelength: and the reflective layer is an insulative multilayer film which is formed on the second electrode and reflects the light with the specific wavelength.
In still another embodiment of the present invention, the semiconductor layer includes at least a pair of cladding layers, the light emitting layer being made of a gallium nitride type compound semiconductor and being formed between the cladding layers; the second electrode has a property of transmitting light with a specific wavelength; and the reflective layer includes: a first insulative layer formed on the second electrode, the first insulative layer reflecting light with a specific wavelength; and a second layer formed on the first layer, the second layer reflecting the light with the specific wavelength at a high reflectivity.
According to another aspect of the present invention, there is provided a method for mounting a light emitting device includes the steps of: forming a semiconductor layer on a substrate which is light transmissive, the semiconductor layer including a light emitting layer; forming a first electrode lower than a plane running parallel through the light emitting layer with respect to the substrate and a second electrode higher than the plane running parallel through the light emitting layer with respect to the substrate; placing first and second lead frames in a predetermined position with respect to a light emitting device, the first lead frame including a first lead pad section to which the first electrode is connected, the second lead frame including a second lead pad section to which the second electrode is connected, and at least one of the first and second lead frames including a die pad section; mounting the substrate onto the die pad section of the at least one of the first and second lead frames; and electrically connecting the first and second electrodes to the first and second lead pad sections, respectively, wherein the first and second lead pad sections are positioned farther away from the substrate than the first and second electrodes, respectively.
The present invention provides a mounting method in which at least one edge or the periphery of an insulative substrate in a gallium nitride type compound semiconductor light emitting device is fixed to a die pad section of a lead frame, thus allowing the light from the insulative substrate to be emitted efficiently therethrough. This invention also eliminates a short circuit between a p-type electrode and an n-type electrode which are formed on the nitride type semiconductor light emitting device by connecting the electrodes to respective lead pad sections of the lead frames by lead wires. Furthermore, an insulative adhesive is used to fix the substrate of the light emitting device to the die pad sections, thereby preventing an electric short circuit between the lead frames and the light emitting device. Thus, the present invention improves the production yield of a gallium nitride type compound semiconductor light emitting device. Preferably, the insulative adhesive is an epoxy resin, a polyester resin, or a cyanoacrylic resin, or the like, which is colorless and transparent and has a 90 percent or more of light transmissivity for a short wavelength range which includes the emission wavelength of a gallium nitride type compound semiconductor light emitting device. Furthermore, because the substrate side of the light emitting device is fixed to the die pad sections, and distortion of the light emitting device caused by the adhesive element is decreased. Therefore, the operating lifetime of the gallium nitride type semiconductor light emitting device can be prolonged.
The first gallium nitride type semiconductor light emitting device according to the present invention has at least one pair of cladding layers and a light emitting layer on an insulative substrate. The device further includes a multilayer film between one of the electrodes (which is farther away from the substrate) and the light emitting layer. The multilayer film includes at least two types of nitride semiconductor layers. For example; when two different types of nitride semiconductor layers are included in the multilayer film, the respective thicknesses thereof are xcex/4n1 and xcex/4n2 (where xcex denotes the emission wavelength of the device, and n1 and n2 denote the respective refractive indices for the emission wavelength xcex). This prevents the light generated in a light emitting layer and directed away from the substrate from being absorbed and scattered by the electrode. Therefore, the light is more efficiently reflected by the multilayer film toward the light transmissive substrate. Thus, a gallium nitride type compound semiconductor light emitting device which has an excellent emission efficiency can be obtained. Preferably, each of the two types of nitride semiconductor layers is doped with a p-type impurity or an n-type impurity in order to facilitate the passage of an externally injected current. The multilayer film preferably includes about 10 to about 100 pairs of such two different types of semiconductor layers. Below about 10 pairs, a sufficient refractive index may not be obtained. Over about 100 pairs, the series resistance of the multilayer film, and hence the drive voltage, of the light emitting device increases. Each of the two types of nitride semiconductor layers may be an InxAlyGa1xe2x88x92xxe2x88x92yN layer (0xe2x89xa6x, 0xe2x89xa6y, and x+yxe2x89xa61), preferably, the two layers are a GaN layer and an AlxGa1xe2x88x92xN layer (0 less than xxe2x89xa60.3), respectively. In the latter, the Al molar fraction is more than 0 and about 0.3 or less. If the Al molar fraction in the AlxGa1xe2x88x92xN layer (0 less than xxe2x89xa60.3) is more than about 0.3, the resistance of the layer may be undesirably high, resulting in an undesirable conductivity.
The second gallium nitride type compound semiconductor light emitting device according to the present invention has at least one pair of cladding layers and a light emitting layer on an insulative substrate. The device further includes a thin film electrode on the side opposite to the insulative substrate with respect to the light emitting layer, an insulative multilayer film, and pad electrodes. These elements are deposited in this order. The insulative multilayer film has at least two different types of insulative layers, in which the respective thicknesses thereof are xcex/4n1 and xcex/4n2 (where xcex denotes the emission wavelength of the device, and n1 and n2 denote the respective refractive indices for the emission wavelength xcex). Therefore, the light generated in a light emitting layer and directed away from the substrate is prevented from being absorbed and scattered by the electrode. Since the insulative multilayer film is formed to surround the light emitting device except for the substrate, the light is more efficiently reflected by the multilayer film toward the light transmissive substrate. Thus, a gallium nitride type compound semiconductor light emitting device which has an excellent emission efficiency can be obtained. Preferred materials which may be used for one of the two types of insulative layers that has a higher refractive index include A12O3, CeF3, CeO2, HfO2, MgO, Nd2O3, NdF3, PbO, Pr6O11, Sc2O3, TiO2, TiO, Y2O3, ZrO2, etc. Preferred materials for the other insulative layer with a lower refractive index include CaF3, MgF2, LaF3, LiF, MgF2, Na3AlF6, NaF, SiO2, Si2O3, etc.
The third gallium nitride type compound semiconductor light emitting device according to the present invention has at least one pair of cladding layers and a light emitting layer on an insulative substrate. The device further includes a thin film electrode on the side opposite to the insulative substrate with respect to the light emitting layer. The device still further includes at least one type of an insulative layer and a metal layer having a high light reflectivity which are deposited to surround the light emitting device except for the substrate side, thereby the light is more efficiently reflected by the multilayer film toward the light transmissive substrate. Thus, a gallium nitride type compound semiconductor light emitting device which has an excellent emission efficiency can be obtained. For the above-mentioned metal, aluminum(Al) or silver(Ag) is preferred to be used since they have a high light reflectivity in a visible wavelength range.
These and other advantages of the present invention will become apparent to those skilled in the art upon reading and understanding the following detailed description with reference to the accompanying figures. | {
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The invention relates generally to the field of orthodontics and, more particularly, to computer-automated orthodontic treatment of teeth.
Tooth positioners for finishing orthodontic treatment are described by Kesling in the Am. J. Orthod. Oral. Surg., 31:297-304 (1945) and 32:285-293 (1946). The use of silicone positioners for the comprehensive orthodontic realignment of a patient's teeth is described in Warunek et al., J. Clin. Orthod., 23:694-700 (1989). Clear plastic retainers for finishing and maintaining tooth positions are commercially available from Raintree Essix, Inc., New Orleans, La. 70125, and Tru-Tain Plastics, Rochester, Minn. 55902. The manufacture of orthodontic positioners is described in U.S. Pat. Nos. 5,186,623; 5,059,118; 5,055,039; 5,035,613; 4,856,991; 4,798,534; and 4,755,139. Other publications describing the fabrication and use of dental positioners include Kleemann and Janssen, J. Clin. Orthodon., 30:673-680 (1996); Cureton, J. Clin. Orthodon., 30:390-395 (1996); Chiappone J. Clin. Orthodon., 14:121-133 (1980); Shilliday, Am. J. Orthodontics, 59:596-599 (1971); Wells, Am. J. Orthodontics, 58:351-366 (1970); and Cottingham, Am. J. Orthodontics, 55:23-31 (1969). Kuroda et al., Am. J. Orthodontics, 110:365-369 (1996) describes a method for laser scanning a plaster dental cast to produce a digital image of the cast. See also U.S. Pat. No. 5,605,459.
U.S. Pat. Nos. 5,533,895; 5,474,448; 5,454,717; 5,447,432; 5,431,562; 5,395,238; 5,368,478; and 5,139,419, assigned to Ornco Corporation, describe methods for manipulating digital images of teeth for designing orthodontic appliances.
U.S. Pat. No. 5,011,405 describes a method for digitally imaging a tooth and determining optimum bracket positioning for orthodontic treatment. Laser scanning of a molded tooth to produce a three-dimensional model is described in U.S. Pat. No. 5,338,198. U.S. Pat. No. 5,452,219 describes a method for laser scanning a tooth model and milling a tooth mold. Digital computer manipulation of tooth contours is described in U.S. Pat. Nos. 5,607,305 and 5,587,912. Computerized digital imaging of the jaw is described in U.S. Pat. Nos. 5,342,202 and 5,340,309. Other patents of interest include U.S. Pat. Nos. 5,549,476; 5,382,164; 5,273,429; 4,936,862; 3,860,803; 3,660,900; 5,645,421; 5,055,039; 4,798,534; 4,856,991; 5,035,613; 5,059,118; 5,186,623; and 4,755,139.
U.S. Pat. No. 5,975,893, assigned to the assignee of the instant invention, describes a system for repositioning teeth using a plurality of individual appliances. The appliances are configured to be placed successively on the patient's teeth and to incrementally reposition the teeth from an initial tooth arrangement, through a plurality of intermediate tooth arrangements, and to a final tooth arrangement. The system of appliances is usually configured at the outset of treatment so that the patient may progress through treatment without the need to have the treating professional perform each successive step in the procedure. | {
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The technical field of this invention is phototherapy and, in particular, methods and devices which employ optical fibers or other flexible light waveguides to deliver radiation to a targeted biological site.
Fiber optic phototherapy is a increasing popular modality for the diagnosis and/or treatment of a wide variety of diseases. For example, in surgery, infrared laser radiation will often be delivered to a surgical site via a hand-held instrument incorporating an optically transmissive fiber in order to coagulate blood or cauterize tissue. Similar fiber optic delivery systems have been proposed for endoscopic or catheter-based instruments to deliver therapeutic radiation to a body lumen or cavity. U.S. Pat. No. 4, 336,809 (Clark) and U.S. Reissue Patent No. RE 34,544 (Spears) disclose that hematoporphyrin dyes and the like selectively accumulate in tumorous tissue and such accumulations can be detected by a characteristic fluorescence under irradiation with blue light. These patents further teach that cancerous tissue that has taken up the dye can be preferentially destroyed by radiation (typically high intensity red light) that is absorbed by the dye molecules during phototherapy.
Others have proposed the use of fiber-delivered radiation to treat artherosclerotic disease. For example, U.S. Pat. No. 4,878,492 (Sinofsky et al.) discloses the used of infrared radiation to heat blood vessel walls during balloon angioplasty in order to fuse the endothelial lining of the blood vessel and seal the surface. Another application of fiber-delivered radiation is disclosed in U.S. Pat. No. 5,053,033 (Clarke) which teaches that restenosis following angioplasty can be inhibited by application of UV radiation to the angioplasty site to kill smooth muscle cells which would otherwise proliferate in response to angioplasty-induced injuries to blood vessel walls.
Nonetheless, a number of problems limit the expanded use of fiber-optic phototherapy. Typically, an optical fiber emits light from only its end face. Thus, the emitted light tends to be focused or at best divergent in a conical pattern and, therefore, exposes only a small region directly in front of the fiber's distal end. The small exposure area limits the power available for phototherapy since overheating of the target tissue must often be avoided.
Although "sideways-emitting" fibers have been proposed to permit greater flexibility in phototherapy, this approach still does not allow uniform irradiation of large volumes of tissue and can also be ill-suited for applications where circumferential uniformity is desired. Because sideways-emitting fibers expose limited regions, they do little to alleviate the problem of "hot spots" which limit the intensity of radiation which can be delivered via the fiber to the treatment site.
Others have proposed diffusive tips for optical fibers to enlarge the region which can be irradiated and/or reduce the potential for overexposure. However, diffusive tips have not been satisfactory for many therapeutic purposes because of their complexity of manufacture and/or because the radiation may not be scattered uniformly enough to alleviate the problem of "hot spots." Prior art diffusive tip structures have not be capable of delivering high power radiation, e.g., on the order of ten watts or more, to facilitate photocoagulation therapy or the like.
There exists a need for better apparatus for fiber-optic phototherapy. In particular, diffusive fiber tip assemblies which can provide circumferential (or large angle) exposure regions in radial directions (e.g., sideways) relative to the fiber axis without hot spots would satisfy a long-felt need in the art. Moreover, diffusive assemblies which illuminate or irradiate an azimuthal angle of less than 360.degree. would meet a particularly important need in the field of minimally-invasive, phototherapeutic surgery. In addition, diffusive fiber tip assemblies which can extend the longitudinal extent of irradiation and provide greater flexibility during use would likewise satisfy a need in phototherapy.
In addition, there exists a need for controlling or reduced unwanted heating effects during phototherapy. Typically, light can be delivered to the site of the desired phototherapeutic reaction by inserting a fiber-optic cable into a patient and maneuvering it to the site of the desired photochemical reaction. The position of the fiber's tip can be monitored by including a metallic structure at the tip and monitoring the position of the metallic structure, either visually or by x-ray fluoroscopy. Additionally, metallic structures are sometimes used to reflect light and to thereby control the illumination field within the patient.
When illuminated by light, these metallic structures absorb a small, yet significant amount of optical energy and reradiate it as heat. Since the metallic structures of phototherapeutic instruments are generally in contact with or proximate to surrounding tissue, the rise in temperature of these structures can inflict heat-induced tissue damage on surrounding tissue or melt catheters in the vicinity of the fiber's tip.
Accordingly, there exists a need for better methods and apparatuses for preventing the metallic structure in phototherapeutic devices from being heated excessively by incident light during use. | {
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1. Field of the Invention
The present invention relates to a plasma process apparatus and a plasma process method for providing a film forming process at a temperature range of about room temperature using plasma with an object to be processed such as a semiconductor wafer.
2. Description of the Related Art
Ordinarily, when semiconductor integrated circuits are manufactured, semiconductor wafers undergo various processes such as a film forming process, an etching process, an oxidizing process, an diffusing process, a reforming process and a removing process of natural oxidation.
In recent years, it is required to process film forming materials at a low temperature in consideration of heat resistance or the like thereof. In order to deal with this requirement, there are proposed plasma process apparatuses using plasma with which reaction can be promoted even though a wafer temperature at a time of processing is low (Patent Documents 1 to 4).
An example of the plasma processing apparatuses is illustrated in FIG. 14. FIG. 14 is a schematic view of an example of conventional lateral-type plasma process apparatus. Referring to FIG. 14, semiconductor wafers W are held by a rotatable and multiple-stage wafer boat 4. The wafer boat 4 may be inserted or extracted into or from the processing container 2 by being moved up and down from a lower side of the processing container 2. Further, a lower end of the processing container 2 may be hermetically sealed by a lid 6. A plasma generating box 8 having a rectangular cross-sectional shape is provided in a sidewall of the processing container 2 along the height of the sidewall.
On both outer sides of the compartment walls of the plasma generating box 8, a pair of independent plasma electrodes 12 facing each other are provided along the height of the plasma generating box 8. A high frequency power of, for example 13.56 MHz, is supplied from a high frequency power source 14 for generating plasma to a region between the plasma electrodes 12. Further, an insulating material 16 is provided on the outer side of the processing container 2 including the outer side of a ceiling portion. Further, a heater 18 for heating the semiconductor wafer W is provided on the inner side surface of the inner side surface of the insulating material 16. A shield cover is provided on the outer side surfaces of the insulating material 16, and connected to ground to thereby prevent the high frequency from leaking outside.
In such a structure, when the high frequency power is supplied to the region between the plasma electrodes 12, plasma is generated. The gas supplied into the plasma generating box 8 is activated by the plasma to thereby generate active species. In this way, a reaction or the like is promoted by the generated active species even though the heating temperature is low. [Patent Document 1] Japanese Unexamined Patent Publication No. 2006-049809 [Patent Document 2] Japanese Unexamined Patent Publication No. 2006-270016 [Patent Document 3] Japanese Unexamined Patent Publication No. 2007-42823 [Patent Document 4] International Publication Pamphlet No. WO 2006/093136
In recent years, there is proposed a new technology called micro electro mechanical systems (MEMS) as assembling using a microfabrication technique. According to MEMS, a three-dimensional device such as a pressure sensor or a microphone may be installed in a small chip. One example of MEMS enables assembling a micromotor having a rotor. For example, when the micromotor is formed, a rotatable microscopic rotor should be formed. Therefore, a microscopic part corresponding to the rotor is previously formed to wrap an entire periphery of the microscopic with an oxide film. Then, a casing for accommodating the rotor is formed by a thin film. Thereafter, the entire oxide film is removed by etching it to thereby make an inside of the casing hollow. Thus, the microscopic rotor is furnished to have a structure in which the microscopic rotor is spontaneously rotatable inside the casing.
The thin film which is necessarily formed in mid-flow of the manufacturing process and removed later is referred to as a sacrificial layer which does not remain in the device. In a case of an oxide film, it is referred to as a sacrificial oxide layer. Film properties of the sacrificial layer and the sacrificial oxide layer are not a problem as long as the sacrificial layer and the sacrificial oxide layer are removed later. Therefore, when an oxide film or the like which is required to have good film properties such as ordinary gate oxide films and ordinary inter-layer insulating films, it is necessary to conduct a forming process under a relatively high temperature in order to acquire good film properties. Meanwhile, there is now being developed a technique of forming the sacrificial oxide layer under a low temperature region in order to form such the sacrificial oxide layer.
In order to form the sacrificial oxide layer, a plasma process apparatus as described with reference to FIG. 14 is used as a film forming apparatus. An aminosilane-based gas such as diisopropylaminosilane (DIPAS) and an active species such as ozone generated by plasma are used, and the sacrificial oxide layer is formed at a relatively low temperature of about room temperature.
However, when the plasma process apparatus as described with reference to FIG. 14 is used in order to form the sacrificial oxide layer, heat generated by plasma is accumulated in a space between the processing container 2 and the insulating material 16 at every batch process. As a result, when the batch processes are continuously conducted, there is a problem that a process temperature gradually increases at every batch process to thereby decrease reproducibility of forming the film. | {
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This invention relates to a method of treating fabrics in the rinse cycle of a textile laundering operation with an antimicrobial agent in order to eliminate odor caused by microbial growth.
An antimicrobial is an agent that destroys or inhibits the growth of microorganisms. The major classes of microorganisms are bacteria, fungi including mold and mildew, yeasts, and algae. Microorganisms can be found in the air, the waters, the human body, soil, wastes, and on all surfaces. The organisms are deposited from the air, food and drink spills, dust, dirt and tracked in soil, and from human excreta such as sweat, urine, and feces. Organisms grow and multiply when there is available a nutrient source of food such as dirt, organic or inorganic material, and living tissue. For growth and multiplication, organisms also require warm temperatures, and moisture. When these conditions exist, microorganisms thrive and flourish. Microbial growth, however, leads to many problems such as unpleasant odors ranging from stale to musty and mildew-like, to putrid and foul smelling, resembling ammonia. The growths also produce unsightly stains, discoloration, and deterioration of many surfaces and materials in which they come into contact. A more serious disadvantage of microbial growth is the production of pathogenic microorganisms, germs, their metabolic products and their somatic and reproductive cell parts, which contribute to the spread of disease, infection, and disorders.
Antimicrobial agents are chemical compositions that are used to prevent such microbiological contaminations by inhibiting, killing and/or removing them and neutralizing their effects of deterioration, defacement, odor, disease or other negative effects. Particular areas of application of antimicrobial agents and compositions are, for example, cosmetics, disinfectants, sanitizers, wood preservation, food, animal feed, cooling water, metalworking fluids, hospital and medical uses, plastics and resins, petroleum, pulp and paper, textiles, latex, adhesives, leather and hides, and paint slurries. In the area of medical applications, antimicrobials are often used as powders, in lotions, creams, ointments and/or delivered in a variety of solvents or directly as over-the-counter or ethical drugs to alleviate, mediate, cure and/or protect people or other animals from disease or cosmetic conditions. Of the diverse categories of antimicrobial agents and compositions, quaternary ammonium compounds represent one of the largest of the classes of antimicrobial agents in use. At low concentrations, quaternary ammonium type antimicrobial agents are bacteriostatic, fungistatic, algistatic, sporostatic, and tuberculostatic. At medium concentrations they are bactericidal, fungicidal, algicidal, and viricidal against lipophilic viruses. Silicone quaternary ammonium salt compounds are well known as exemplified by U.S. Pat. No. 3,560,385, issued Feb. 2, 1971, and the use of such compounds as antimicrobial agents is taught, for example; in a wide variety of patents such as U.S. Pat. Nos. 3,730,701, issued May 1, 1973, and 3,817,739, issued Jun. 18, 1974, where the compounds are used to inhibit algae; 3,794,736, issued Feb. 26, 1974, and 3,860,709, issued Jan. 14, 1975, where they are employed for sterilizing or disinfecting a variety of surfaces and instruments; and 3,865,728, issued Feb. 11, 1975, where the compounds are used to treat aquarium filters. Published unexamined European Application No. 228464 of Jul. 15, 1987, teaches that microorganisms on multi-cellular plants can be killed by the application thereto of an aqueous mixture of a surfactant and an organosilicon quaternary ammonium compound. U.S. Pat. No. 4,564,456, issued Jan. 14, 1986, discloses organosilanes as anti-scale agents in water systems. In a particular application of an antimicrobial silicone quaternary ammonium compound, a paper substrate is rendered resistant to the growth of microorganisms in U.S. Pat. No. 4,282,366, issued Aug. 4, 1981. In U.S. Pat. No. 4,504,541, issued Mar. 12, 1985, an antimicrobial fabric is disclosed which is resistant to discoloration and yellowing by treatment of the fabric with a quaternary ammonium base containing an organosilicone. U.S. Pat. No. 4,615,937, issued Oct. 7, 1986, as well as its companion U.S. Pat. No. 4,692,374, issued Sep. 8, 1987, relate to wet wiper towelettes having an antimicrobial agent substantive to the fibers of the web and being an organosilicon quaternary ammonium compound. In a series of Burlington Industries, Inc. U.S. Pat. Nos. 4,408,996, issued Oct. 11, 1983, 4,414,268, issued Nov. 8, 1983, 4,425,372, issued Jan. 10, 1984, and 4,395,454 , issued Jul. 26, 1983, such compounds are disclosed to be useful in surgical drapes, dressings, and bandages. This same assignee also discloses these compounds as being employed in surgeons' gowns in U.S. Pat. Nos. 4,411,928, issued Oct. 25, 1983, and 4,467,013, issued Aug. 21, 1984. Organosilicon quaternary ammonium compounds have been employed in carpets, in U.S. Pat. No. 4,371,577, issued Feb. 1, 1983; applied to walls, added to paints, and sprayed into shoes, in U.S. Pat. No. 4,394,378, issued Jul. 19, 1983; formulated as aqueous emulsions in U.S. Pat. No. 4,631,273issued Dec. 23, 1986; applied to polyethylene surfaces and used in pillow ticking in U.S. Pat. No. 4,721,511, issued Jan. 26, 1988; in flexible polyurethane foams of fine-celled, soft, resilient articles of manufacture in U.S. Pat. No. 4,631,297, issued Dec. 23, 1986; and mixed with a surfactant in British Patent No. 1,386,876, of Mar. 12, 1975, and in Japanese Kokai Application No. 58-156809, filed Aug. 26, 1983, of Sanyo Chemical Industries, Ltd. Some general, more domestic type applications of these compounds, has included their use in a dentifrice as in U.S. Pat. No. 4,161,518 issued Jul. 17, 1979; in a novel laundry detergent in U.S. Pat. No. 4,557,854, issued Dec. 10, 1985; as a hair conditioner in U.S. Pat. No. 4,567,039 , issued Jan. 28, 1986; and in a soft contact lens disinfectant solution in U.S. Pat. No. 4,615,882, issued Oct. 7, 1986. In U.S. Pat. No. 4,614,675, issued Sep. 30, 1986, properties can be influenced by mixing the silicone quaternary ammonium salt compounds with certain siloxanes.
Other typical uses of organosilicon quaternary ammonium compounds in accordance with the prior art can be seen from U.S. Pat. Nos. 4,005,024; '025; '028; and '030; each issued on Jan. 25, 1977, and relating to hard surface rinse aids and detergents for hard surfaces. Contact lenses are treated with an organosilane in U.S. Pat. No. 4,472,327, issued Sep. 18, 1984. In U.S. Pat. No. 4,682,992, issued Jul. 28, 1987, glass spheres are treated with the compounds and employed as filters. The compounds are used to treat swine dysentery in U.S. Pat. No. 4,772,593, issued Sep. 20, 1988; in a wet wiper in U.S. Pat. No. 4,781,974, issued Nov. 1, 1988; applied to a polyester fabric in U.S. Pat. No. 4,822,667, filed Apr. 18, 1989; and adhered to polyamide yarn in U.S. Pat. No. 4,835,019, issued May 30, 1989. In Canadian Patent No. 1,217,004, granted Jan. 27, 1987, organosilane quaternary ammonium compounds are formulated into bleaches that are applied to hard surfaces such as bath tubs, wash basins, toilets, drains, and ceramic tile floors.
Modern washing machines work automatically and the operator places the laundry in the machine, pours in the detergent, and sets the controls. One set of controls determines whether the machine employs hot, warm, or cold water. Water enters the machine through hoses connected to the hot and cold water pipes. The operator also sets controls in order to select the length of washing and rinsing time, and the amount of water that enters the machine. The machine is powered by an electric motor and includes a filter that removes lint, and automatic dispensers for bleach and fabric softeners. A wash cycle typically includes four stages. In the wash cycle, after water fills the wash tub, an agitator reverses direction alternately and moves the laundry through the water and detergent, and forces water through the items of laundry. The washer is then emptied of all of the wash liquor in the spin cycle and the clothes are spun to remove excess water. In the rinse cycle, clean water is added along with the fabric softener and the clothes are again agitated. The washer is emptied of rinse liquor and the clothes are spun in a final spin cycle during which time excess water is removed and pumped out of the machine through a drain hose. The clothing is then ready to be removed from the machine and dried in a dryer or hung on a clothesline until dry.
Fabric treatments for use in such machines are well known in the art. For example, in British Patent No. 1,549,180, issued Jul. 25, 1979, Dumbrell et al disclose a fabric softener which includes, in addition to the softening benefit, the additional benefits of easier ironing, antistatic properties, pleasanter feel, and soil release properties. The additional benefits are stated to be derived from the inclusion along with a cationic quaternary ammonium fabric softening agent, of a silicone compound which is said to be an aqueous emulsion of a linear siloxane.
Specifically, Dumbrell et al relate to fabric softening compositions that include an aqueous dispersion of a cationic softening compound, and a silicone emulsion. The cationic compound is disclosed to be one or more or mixtures of a combination of quaternary mono-ammonium compounds such as tallowtrimethylammonium chloride, and ditetradecyldimethylammonium chloride; quaternary imidazolinium compounds; polyammonium compounds such as acid salts of diamine compounds, and polyamine salts; and polyalkyleneimine salts. The silicone emulsion is preferably a linear dialkyl or alkylaryl siloxane which may be partially or wholly fluorinated, or substituted with cationic nitrogen groups. The viscosity is disclosed to be, at twenty-five degrees Centigrade, at least one hundred and up to eight thousand centistokes. The weight ratio of siloxane content of the emulsion to the dispersion is five to one, to one to one-hundred. Representative compositions are said to be cationic emulsion polymerized dimethylsiloxanes, with the emulsifying agent being, for example, ditallowyldimethylammonium chloride; quaternized polysiloxanes such as dipyridinium polydimethylsiloxane; and aminofunctional linear polysiloxanes such as polydimethylsiloxanes containing dimethylaminopropyl groups.
It is not new to employ an organosilicon quaternary ammonium compound in a laundering environment. For example, in U.S. Pat. No. 4,557,854, issued Dec. 10, 1985, a powdered heavy duty laundry detergent is disclosed which contains insoluble particulate materials, the surfaces of which have been treated with a silane. It is also not new to employ organosilicon compounds in the rinse cycle of a fabric treating laundering operation. Aminofunctional polysiloxanes have been included as an additive in the rinse cycle in the aforementioned British Patent No. 1,549,180, granted Jul. 25, 1979 to Dumbrell et al. What is believed to be new and unique and what is disclosed in the present invention, however, is the concept of employing an organosilane which is an organosilicon quaternary ammonium compound in the rinse cycle of a fabric laundering operation.
There is a basic distinction between the aminofunctional polysiloxane employed in the rinse cycle in the British Patent 1,549,180, and the organosilane quaternary ammonium compound of the present invention when it is employed in the rinse cycle. While both compositions are organosilicon compounds, and while both are employed in the rinse cycle, the two compositions function in the rinse cycle in an entirely different fashion one from the other. For example, in the rinse cycle, the silane end of the organosilicon quaternary ammonium molecule of the present invention is substantive to natural textile surfaces such as cotton, wool, and jute, but the siloxane end of the aminofunctional organosilicon molecule of Dumbrell is not substantive to such surfaces. The organofunctional end of the organosilane quaternary ammonium molecule of the present invention is substantive to wetted surfaces and anionic surfaces such as synthetic textiles of the types nylon and polyester, but the aminofunctional end of the polysiloxane molecule of Dumbrell et al is not substantive to such surfaces. Further, the organosilane quaternary ammonium compounds of the present invention are antimicrobially active and hence are capable of killing microorganisms and preventing their proliferation, while the aminofunctional polysiloxanes of Dumbrell et al are not active antimicrobials. In addition, because of the substantive textile affinity of both ends of the molecule of the organosilane quaternary ammonium compounds of the present invention, the antimicrobial treatments rendered by these compounds are durable. This the aminofunctional polysiloxane of Dumbrell et al is incapable of duplicating.
The "unbound" antimicrobials of the prior art are not the equivalent of the "bound" antimicrobial organosilane of the present invention because the unbound antimicrobials do not perform substantially the same function, in substantially the same way, to produce substantially the same results, as do the bound silanes of the present invention. The function differs because the bound antimicrobial is permanent whereas the unbound types are easily washed away or rubbed from the surface. The compounds of the present invention are not only durable but retain their antimicrobial activity after some ten laundering cycles, and only slightly diminish in their activity after as many as twenty-five laundering cycles. The bound silanes of the present invention retain an effective kill level of microorganisms. The manner in which the bound silane functions differs from the unbound types, since the bound silane attaches itself to the surface to which it is applied, whereas the unbound types are mere coatings which are not substantive. This is significant since the silane antimicrobial will continue to prevent reinfestation, and enables one to utilize the intrinsic antimicrobial activity of the silane treated surface to kill transient microbes, long after the unbound types of antimicrobials have been depleted of their activity. Further, the bound silanes of the present invention destroy, reduce, and inhibit the growth and multiplication of bacteria, fungi, and other pathogenic microorganisms, by the disruption of cell membranes, a mechanism absent from conventional unbound antimicrobial materials. The results produced by the bound silanes is not the same as the results produced by the unbound types, since the bound silanes provide a prolonged antimicrobial activity and continue to kill and inhibit the proliferation of potentially destructive microorganisms, versus mere temporary and superficial protection offered by the unbound category of material.
Thus, it should be apparent that the method of the present invention in employing the bound antimicrobially active organosilicon quaternary ammonium compounds is far removed from methods that have been previously disclosed by the prior art.
Among the numerous attempts to alleviate the problems of microorganisms on surfaces have involved the use of soaps, detergents, and surface cleaners. The treatments, however, have for the most part included an unbound category of antimicrobial which is not actually bonded to the surface sought to be treated, and therefore is consumed by the microorganisms, with the result that the unbound antimicrobial is depleted and washed away during routine cleansing. As this diffusion continues, the concentration of the active ingredient becomes diluted below effective levels, with the result that the microorganisms sought to be inhibited, adapt and build up a tolerance, becoming immune to what was once an effective treatment dose. Such unbound diffusible antimicrobials have therefore been found to be limited in their ability to offer broad spectrum control of microorganisms, in contrast to the bound type of antimicrobial which remains chemically attached to the surface to which it is applied providing for a surface that prevents recolonization by the microflora associated therewith. Diffusing types of antimicrobials also often suffer from the propensity to transfer percutaneously, giving rise to sensitization and irritation immunological responses, and raising serious questions as to their ultimate fate within the body and body systems.
Bound antimicrobials kill organisms on contact and continue to kill organisms without being diffused or leached from the surface. Thus, the bound antimicrobial leaves behind an effective level of active ingredient and is able to control a broad spectrum of microorganisms including gram negative and gram positive bacteria, mold, mildew, fungi, yeast, and algae. An exemplary category of bound antimicrobial is an alkoxysilane quaternary ammonium compound, and such alkoxysilane quaternary ammonium compounds have been found to be more effective at reducing the number of microorganisms, and inhibiting microbially generated odors, than conventional organotin compounds and other organic quaternary ammonium compounds. The silanes of the present invention immobilize on surfaces and bond thereto to provide a coating of immobilized antimicrobial, unlike conventional materials.
In the present invention, this bound characteristic of alkoxysilane quaternary ammonium compounds, as well as their capabilities of performing at effective kill levels beyond prior art types of compositions, is taken advantage of in the treatment of fabrics, in order to reduce or substantially eliminate the incidence of microorganisms, germs, their metabolic products and their somatic and reproductive cell parts, which contribute to the spread of such microbes. | {
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Manual transmissions of countershaft design and that can be actuated with manual shifting devices have long been in use in drive-trains of motor vehicles. In a conventional countershaft transmission loose wheels and fixed wheels, which mesh in pairs, are usually arranged in a number of gearset planes. In each case, the shifting of transmission gears is accomplished by opening a gear clutch of a gear that is engaged and closing a gear clutch of a target gear, whereby a rotationally fixed connection between a loose wheel and a gear shaft on which the loose wheel concerned is mounted to rotate is released, whereas another rotationally fixed connection between a loose wheel and a transmission shaft is formed. Before the formation of the force closure in the drive-train, the rotating components of the target gear that have to be engaged are synchronized. In order to save space and weight the gear clutches, i.e. the synchronizing devices or claw clutches of the shifting devices, are where possible formed as dual clutches such that two gear clutches or synchronizing devices at a time are arranged in shifting packets that can be actuated from both sides. The number of gears in such transmissions usually corresponds to the number of gearset planes.
To obtain more gears with a given number of gearset planes or, for a set number of gears, to produce a more compact and cost-saving structure with fewer gearset planes, it is already known to set up shifting logic systems in which, to produce the transmission gears, existing gearset planes and gear clutches are used more than one at a time. In such manual transmissions, due to the smaller number of components, to produce a force flow in the transmission when the gears are engaged in each case more than one gear clutch is closed or is kept closed.
The design of a manual shifting device for such a transmission is relatively complex, as shown for example by DE 10 2008 017 862 A1 from which an operating device for a 7-gear manual transmission with an H-type shifting pattern is known.
Thus, such transmissions are usually actuated by means of actuators which are controlled automatically by a control unit by virtue of a shifting program. But if such a compact manual transmission is to be operated by a driver as a manually shifted transmission with shift-lever actuation in a logical shift pattern, then in order to limit the design complexity it is appropriate to actuate at least part of the gearshift, i.e. in each case at least one of the gear clutches to be engaged for the gearshift, automatically with the help of an actuator.
When the shift lever is guided in the gearshift consoles of such a manual-shift device of an at least partially automated transmission, shift processes are initiated by actuator means and/or control elements of the transmission are operated manually. For this, gear clutches can be actuated both by shifting movements in the shifting gates of the gearshift console and also by selector movements in the selection gates of the gearshift console. This entails a correspondingly high level of complexity for the actuators and their control.
DE 10 2005 057 813 A1 describes a manual shift transmission with an input shaft, an output shaft arranged coaxially with and behind it, and a countershaft arranged with its axis parallel to these shafts. The transmission gears can be engaged in each case by closing more than one gear clutch. The transmission comprises five gearset planes for the production of six forward gears and one reverse gear, such that the fifth gear is designed as a direct gear and the sixth gear as an overdrive gear, i.e. a fast-driving gear. The third and fourth gearset planes consist in each case of two meshing loose wheels, the loose wheels on the countershaft side of the two gearset planes being firmly connected with one another. On the input shaft, the output shaft and the countershaft are arranged a total of seven gear clutches, arranged as three dual gear clutches and one single clutch. By suitable adaptation of the radial dimensions of the gear clutches, all the gear clutches can be mechanically actuated by way of a single shifting shaft or shifting roller.
DE 10 2010 043 564 A1 describes a manual shift transmission with a manual shifting device, which is designed as a group transmission. This transmission comprises an input shaft, an output shaft arranged coaxially with and behind it, and a countershaft arranged parallel to the shafts. With five gearset planes, six forward and one reverse gear can be obtained. The first two gearset planes act as a splitter group, wherein the second gearset plane is also active with the other gearset planes in a main group. Of the total of six gear clutches three are formed as dual clutches, and one of the dual clutches is connected to the input shaft while the other two dual clutches are connected to the output shaft. All the loose wheels are arranged on the input shaft and the output shaft, whereas all the fixed wheels are connected to the countershaft. The transmission can be shifted in an H-shifting pattern having a plurality of shifting gates and a selection gate orientated transversely thereto, such that when any gear is engaged, two of the gear clutches are in each case closed and in the shifting gates with two opposite gears in each case one of the gear clutches in the two gears is closed. Several of the gear clutches can be actuated both in the selection gates and also in one or more of the shifting gates. A comparable transmission is also known from DE 197 53 061 C1. | {
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The present invention relates generally to oil and gas well completion methods, and more particularly, to well completion methods utilizing rubber latex compositions in subterranean formations containing salt zones.
A variety of oil and gas well completion methods have heretofore involved the use of hydraulic cement compositions. Such cement compositions are usually comprised of a water slurry of Portland cement and various additives such as set time accelerators, retarders, fluid loss reducers, dispersants, etc. The cement slurries are pumped into completion or remedial locations within well bores and/or subterranean formations penetrated thereby and allowed to set into hard impermeable masses.
A principal well completion technique which utilizes a cement composition is known as primary well cementing. Primary well cementing involves the placement of a cement composition in the annulus between the walls of the well bore and a conduit, e.g., casing, disposed therein, and allowing the cement composition to set therein whereby the exterior surfaces of the conduit are bonded to the walls of the well bore. The bonding of the conduit within the well bore serves to maintain the conduit in place and to prevent formation fluids from communicating between subterranean formations or zones or to the surface by way of the annulus.
While primary cementing operations utilizing Portland cement compositions have generally been very successful, when such primary cementing is carried out in wells through salt zones wash-out areas in the formation can occur as a result of salt dissolution into non-salt saturated aqueous well bore fluid. Salt zones can also have adverse effects on freshwater cement compositions used in well completion methods, and therefore, salt saturated slurries are often necessary for cementing through these zones. However, the use of a salt saturated cement slurry is often undesired because the salt increases the length of time required for the cement to set. Hence, there are needs for improved well completion methods utilizing compositions which provide protective barriers between the salt zones and fluids being used in such methods. | {
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This invention pertains to incandescent light, especially to a therapeutic incandescent light device that produces a focused and controlled source of light and heat to assist in the prevention and elimination of congestion due to injury, inflammation, or infection of the external, middle, or inner human ear and structures thereof. | {
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1. Field of the Invention
This invention is generally related to laser processing of materials and more specifically to an improved method of welding or sealing together the edges of juxtaposed, spaced apart glass sheets in a vacuum.
2. Description of the Prior Art
In our U.S. Pat. No. 4,683,154, which is incorporated herein by reference, we described a laser sealed vacuum insulation window. The window comprises two juxtaposed sheets of glass held spaced apart in relation to each other by a plurality of spherical glass beads, and the edges of the juxtaposed glass sheets are glass-welded together to provide a sealed, evacuated space between the juxtaposed glass sheets that is completely glass-sealed from the exterior. The edges of the juxtaposed glass sheets are welded together in a vacuum chamber by a laser beam that is focused and steered around the edges of the glass sheets. The laser used to melt and weld the edges together had to be of a wavelength that is absorbed by the glass and of sufficient power to raise the temperature of the glass edges to the melting temperature of the glass, which is about 1,200.degree. C. to 1,300.degree. C. for borosilicate glass.
Unfortunately, the laser welding of the edges of the juxtaposed glass sheets to seal the vacuum space has been hindered by several technical problems that occur when the glass is heated above its annealing temperature in the vacuum chamber. First, dissolved gases in the glass tend to nucleate bubbles in the weld line, which become defects that can produce flaws and failures of the vacuum tight seal. Second, the molten glass at the weld point vaporizes and contaminates the mirror in the vacuum chamber that is used to steer the laser beam around the edges of the glass sheets being welded, which decreases specularity of the mirror and diffuses the laser beam, thus causing a loss of power and frustrating the welding process, and, if allowed to continue, could result in excessive absorption of the laser beam and consequent heat damage to the mirror. | {
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Conventional costume systems or methods are directed to apparel. The present disclosure generally relates to apparatuses worn by users or to a costume toy that arouses interest or emotion using display designs, slogans, pictures, of other like types of display. More particularly, the disclosure relates to apparatus used to entertain and make people laugh, happy, aroused, playful, or silly.
Display apparatuses of various kinds are widely used to display information or to promote various materials to the public. Different types of displays can be utilized including billboards, signs, banners, decals, pins, bumper stickers, and the like. The information included on such display apparatuses include designs, slogans, advertisements, messages, and pictures. Such apparatuses are commonly used by commercial entities, political organizations, charitable organizations, educational institutions, and other large entities to promote various causes and endeavors. Individual persons or smaller entities also create, use, and distribute display apparatuses for such reasons.
Wearable display apparatuses are one type of display apparatus that are commonly used with several advantages. One advantage is that most apparatuses are small and therefore easy and convenient to use. Once the display apparatus is affixed to a user, it can potentially attract viewers wherever tire user carries it. The public can view the apparatus while the wearer participates in normal daily activities, such as when talking to neighbors or friends, going shopping, walking down a street or through a public area, etc.
Display apparatuses are usually affixed to a user in a manner intended to display information to the public. However, wearable display apparatuses and the accompanying designs are often not be sufficiently noticeable achieve the desired degree of attention from the public. Such lack of appeal often results from a lack of creative design; unattractive design detail; large complex and bulky configurations; and other like shortcomings. Such unnoticeable or bland designs may prevent the display apparatuses from attracting attention and thus undermine the purpose of such display apparatuses particularly where a significant amount of time and resources are employed in creating and distributing the apparatus. Thus, display apparatuses are desirable that attract viewers while being portably attached to a user. Such apparatus can be used to entertain and excite viewers at various occasions including parties, events, performances, personal residences, bedrooms, and any other place. The prior-art does not disclose entertaining or alluring materials for adults including petite sized cones to enhance the shape of body parts while presenting lovable sayings and suggestions using a LED display apparatus.
Therefore, a need exists for a new and improved a costume toy that would provide the above-mentioned benefits. In this regard, the present disclosure substantially fulfills this need. The costume toy according to the present disclosure substantially departs from the conventional concepts and designs of the prior art, and in doing so provides an apparatus primarily developed for the purpose of entertaining and alluring a user using petite sized cones provided with LED lights. | {
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The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
An increasing amount of sensitive data is displayed on mobile devices, such as banking information, e-mail, insurance account information, etc. Combined with the increasing screens sizes of mobile computing devices, it may be possible for a malicious party to look over someone's shoulder (or otherwise eavesdrop), and view sensitive data displayed within the viewport, or viewing region, of the display of a computing device. Although many applications that display sensitive data authenticate a user via a password and user name, these traditional authentication techniques may not prevent others from viewing sensitive data from a distance. | {
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1. Field of the Invention
The present invention relates to a printed circuit board unit comprising a printed circuit board and an electronic component such as a chip mounted on the surface of the printed circuit board through solders.
2. Description of the Prior Art
Soldering is often employed to mount electronic components such as semiconductor devices or bare chips on a printed circuit board in a multi-chip module (MCM) or a semiconductor package. Soldering is also employed to mount electronic components such as the MCMs on a printed circuit board of a larger size, namely, a motherboard. When the individual bare chip or MCM is to be exchanged in the MCM or motherboard, solders must be broken or removed to release bonding between input/output terminals on the bare chip or the MCM and input/output pads arranged on the printed circuit board. For example, an exchanging operation is designed to detach the older bare chip or MCM from the printed circuit board when the solders are subjected to heat of temperature higher than the melting point of the solders. A new bare chip or MCM is thereafter mounted on the printed circuit board by soldering input/output terminals of the new bare chip or MCM to the input/output pads which have previously received the input/output terminals of the old bare chip or MCM.
It is well known that part of the old solder still remains on the input/output pad on the printed circuit board even after the old bare chip or MCM is detached in the above-described exchanging operation. When a new bare chip or MCM is mounted on the printed circuit board, a new solder of a predetermined amount is added to the old solder remaining on the input/output pad. An excessive solder may induce a short between the adjacent input/output terminals.
In particular, the respective input/output pads are not expected to keep solders of a uniform amount remaining thereon. When a bare chip or MCM employs a plurality of input/output terminals such as a ball grid array (BGA) and a pin grid array (PGA), the bare chip or MCM may suffer from the solders of a varied height on the input/output pads. The input/output terminals of the new bare chip or MCM may in part fail to touch the surface of the input/output pads on the printed circuit board. No electric connection can thus be achieved partly.
In view of the above inconvenience, the solders remaining on the input/output pads should be wiped out before a new bare chip or MCM is mounted. For example, the printed circuit board along with the remaining bare chips or MCMs is subjected to another heat so as to melt the solders remaining on the input/output pads. Heat is sometimes repeatedly applied to the printed circuit board more than twice until the solders are completely wiped out. Repeated application of heat is supposed to damage and shorten the life of the printed circuit board, and bare chips or MCMs remaining on the printed circuit board. It sometimes deteriorates the wetness of the input/output pads to solders. | {
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The present invention relates to a magnetic tunnel device incorporating a pair of magnetic layers laminated through a tunnel barrier layer to pass a tunnel current from either of the magnetic layers to another magnetic layer and structured such that the conductance of the tunnel current varies depending on a polarizability of magnetization of the pair of the magnetic layers, a manufacturing method therefor and a magnetic head.
Hitherto, a magnetic tunneling effect has been reported which can be obtained from a layer structure in which a thin insulating layer is held between a pair of magnetic metal layers. In this case, the conductance of a tunnel current which flows in the insulating layer varies depending on the relative angle of the pair of the magnetic metal layers. That is, the layer structure in which the thin insulating layer is held between the pair of the magnetic metal layers has a magnetic resistance effect with respect to the tunnel current which flows in the insulating layer.
The magnetic tunneling effect enables a magnetic resistance ratio to theoretically be calculated from the polarizability of magnetization of the pair of the magnetic metal layers. When Fe is employed as the material of the pair of the magnetic metal layers, a magnetic resistance ratio of about 40% can be expected.
Therefore, the magnetic tunnel device having at least the layer structure in which the thin insulating layer is held by the pair of the magnetic metal layers has attracted attention as a device for detecting an external magnetic field.
A magnetic tunnel device of the foregoing type usually has a structure that metal oxide is employed to constitute the thin insulating layer. If the metal oxide is employed to constitute the insulating layer, a pinhole or the like is, however, formed. In this case, short circuit undesirably occurs between the magnetic metal layers forming the pair. When the metal oxide is employed to constitute the insulating layer, a satisfactory degree of oxidation cannot sometimes be obtained. The tunnel barrier becomes too incomplete to always realize the magnetic tunneling effect.
In view of the foregoing, an object of the present invention is to provide a magnetic tunnel device with which a tunnel current can reliably be introduced into a tunnel barrier layer to exhibit a stable magnetic tunnel effect, a manufacturing method therefor and a magnetic head.
A magnetic tunnel device according to the present invention comprises: first and second magnetic layers laminated though a tunnel barrier layer, wherein the magnetic tunnel device has a region in which change in a magnetic resistance ratio with respect to change in a voltage applied in such a manner that the second magnetic layer has a lower potential as compared with the potential of the first magnetic layer is smaller than change in a magnetic resistance ratio with respect to change in a voltage applied in such a manner that the second magnetic layer has a higher potential as compared with the potential of the first magnetic layer.
The magnetic tunnel device having the above-mentioned structure and according to the present invention is structured such that the voltage is applied in such a manner that the potential of the second magnetic layer is lower than that of the first magnetic layer. Therefore, electrons flow from the second magnetic layer to the first magnetic layer through the tunnel barrier layer. At this time, the quantity of change in the magnetic resistance ratio in the magnetic tunnel device is reduced as compared with a case in which electrons are allowed to flow in an inverse direction. That is, the voltage is applied in such a manner that the potential of the second magnetic layer is lower than that of the first magnetic layer. Thus, the dependency of the magnetic resistance ratio of the magnetic tunnel device on the voltage is inhibited. Therefore, in the magnetic tunnel device, stable tunnel currents flow to the tunnel barrier layer without any dependency on the level of the voltage.
A magnetic tunnel device according to the present invention comprises: a first magnetic layer; a tunnel barrier layer formed on the first magnetic layer and structured such that the degree of oxidation is raised from the first magnetic layer; and a second magnetic layer formed on the tunnel barrier layer, wherein electrons are supplied from the second magnetic layer to the first magnetic layer so that tunnel currents are supplied to the tunnel barrier layer.
The magnetic tunnel device structured as described above and according to the present invention is arranged such that metal is oxidized in stages on the first magnetic layer so that the tunnel barrier layer is formed. That is, the tunnel barrier layer having a lowest degree of oxidation is formed on the first magnetic layer. Therefore, the tunnel barrier layer has a satisfactory adhesiveness with respect to the first magnetic layer. Moreover, the magnetic tunnel device is structured such that a direction in which electrons are supplied to the tunnel barrier layer is determined. Therefore, in the magnetic tunnel device, stable tunnel currents are supplied to the tunnel barrier layer without any dependency on the voltage.
A method of manufacturing a magnetic tunnel device according to the present invention comprises the steps of: forming a first magnetic layer; forming a tunnel barrier layer on the first magnetic layer by oxidizing metal in stages; and forming a second magnetic layer on the first magnetic layer through the tunnel barrier layer.
The method of manufacturing a magnetic tunnel device structured as described above and according to the present invention is arranged such that the tunnel barrier layer is formed by oxidizing metal in stages. Therefore, the adhesiveness of the tunnel barrier layer with respect to the first magnetic layer can be improved. Since the foregoing method is structured such that metal is oxidized in stages to form the tunnel barrier layer, a magnetic tunnel device can be manufactured in which tunnel currents are stably flow without any dependency on the voltage.
A magnetic head according to the present invention comprises: a magnetic tunnel device incorporating first and second magnetic layers laminated though a tunnel barrier layer, wherein the magnetic tunnel device has a region in which change in a magnetic resistance ratio with respect to change in a voltage applied in such a manner that the second magnetic layer has a lower potential as compared with the potential of the first magnetic layer is smaller than change in a magnetic resistance ratio with respect to change in a voltage applied in such a manner that the second magnetic layer has a higher potential as compared with the potential of the first magnetic layer, and the magnetic tunnel device serves as a sensitive portion.
The magnetic bead having the above-mentioned structure and according to the present invention is structured such that the voltage is applied to the magnetic tunnel device in such a manner that the potential of the second magnetic layer is lower than that of the first magnetic layer. Therefore, electrons flow from the second magnetic layer to the first magnetic layer through the tunnel barrier layer. At this time, the quantity of change in the magnetic resistance ratio in the magnetic tunnel device is reduced as compared with a case in which electrons are allowed to flow in an inverse direction. That is, the voltage is applied in such a manner that the potential of the second magnetic layer is lower than that of the first magnetic layer. Thus, the dependency of the magnetic resistance ratio of the magnetic tunnel device on the voltage is inhibited. Therefore, in the magnetic head, the magnetic tunnel device serving as the sensitive portion can stably be operated.
A magnetic head according to the present invention comprises: a magnetic tunnel device incorporating a first magnetic layer; a tunnel barrier layer which is formed on the first magnetic layer and in which the degree of oxidation is raised from the first magnetic layer; and a second magnetic layer formed on the tunnel barrier layer, wherein electrons are supplied from the second magnetic layer to the first magnetic layer to cause tunnel currents to flow to the tunnel barrier layer, and the magnetic tunnel device serves as a sensitive portion.
The magnetic head structured as described above and according to the present invention is arranged such that the magnetic tunnel device having the tunnel barrier layer formed on the first magnetic layer by oxidizing metal in stages serves as the sensitive portion. That is, the tunnel barrier layer having a lowest degree of oxidation is formed on the first magnetic layer. Therefore, the tunnel barrier layer has a satisfactory adhesiveness with respect to the first magnetic layer. Moreover, the magnetic head is structured such that a direction in which electrons are supplied to the tunnel barrier layer is determined. Therefore, in the magnetic heads, stable tunnel currents are supplied to the tunnel barrier layer without any dependency on the voltage. As a result, the magnetic tunnel device serving as the sensitive portion can stably be operated. | {
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An opening which can be opened up by a sliding roof, or possibly also an opening which is closed off by a glass roof, in a vehicle roof is usually provided with a sunshade element which, in order to provide protection from solar radiation, can be moved by the vehicle occupants such that it fully or partially covers the opening or the glass roof on the inside. Such protection from the sun is also important because incident solar radiation can blind the driver. Here, even a small gap between a front end of the sunshade element and the edge of the roof opening, through which blinding solar radiation can still pass, can prove to be disturbing. It is therefore desirable for the front end of the sunshade element, in its closed position, to completely cover the front part of the roof opening to the interior space.
In recent years, use has increasingly been made of sunshade assemblies in which the sunshade element is moved by a motor as opposed to being moved manually. Here, tolerances which add up in the assembly can lead to an end setting of the front end of the sunshade element varying within a tolerance path. Such tolerances arise for example from the movement of the force-transmitting drive element which moves the sunshade element, and which is generally a cable guided to be resistant to tension and rigid in compression. Further tolerances arise, when using a roller blind as a sunshade element, during the winding and unwinding of the roller blind, or else from structural tolerances.
To compensate for these tolerances, a trim panel has hitherto been attached to the front end of the roof opening. This trim panel covers the front end of the sunshade element in its closed position in order to ensure that there is not an exposed gap. The disadvantage of this solution is that the clear width of the roof opening is reduced, which gives the vehicle occupants the impression that the roof opening is smaller.
Such a known solution is shown in FIG. 1, in which a front end of a sunshade element 1, in its closed position, moves beyond an upper end of a roof lining 2, and a gap formed between the roof lining 2 and a roof frame 3 is covered by a trim panel 4.
It is an object of the invention to provide a sliding roof sunshade assembly for a vehicle, in which substantially the entire clear width of the roof opening is opened up in the open state of the sunshade element. | {
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1. Field of the Invention
The present invention relates generally to electrical substrates, and more particularly to a support circuit that can be connected to a semiconductor chip to provide a semiconductor chip assembly.
2. Description of the Related Art
Semiconductor chips have input/output pads that must be connected to external circuitry in order to function as part of an electronic system. The connection media is typically an array of metallic leads (e.g., a lead frame) or a support circuit (e.g., a substrate), although the connection can be made directly to a circuit panel (e.g., a mother board). Several connection techniques are widely used. These include wire bonding, tape automated bonding (TAB) and flip-chip bonding. Wire bonding is by far the most common. In this approach, wires are bonded, one at a time, from the chip to external circuitry by ultrasonic, thermocompression or thermosonic processes. TAB involves bonding gold-bumped pads on the chip to external circuitry on a polymer tape using thermocompression bonding. Both wire bonding and TAB require mechanical force such as pressure or a burst of ultrasonic vibration and elevated temperature to accomplish metallurgical welding between the wires or bumps and the designated surface.
Flip-chip bonding involves providing pre-formed solder bumps on the pads, flipping the chip so that the pads face down and are aligned with and contact matching bond sites, and melting the solder bumps to wet the pads and the bond sites. After the solder reflows it is cooled down and solidified to form solder joints between the pads and the bond sites. Organic conductive adhesive bumps with conductive fillers in polymer binders have been used in place of solder bumps, but they do not normally form a metallurgical interface in the classical sense. A major advantage of flip-chip bonding over wiring bonding and TAB is that it provides shorter connection paths between the chip and the external circuitry, and therefore has better electrical characteristics such as less inductive noise, cross-talk, propagation delay and waveform distortion. In addition, flip-chip bonding requires minimal mounting area and weight which results in overall cost saving since no extra packaging and less circuit board space are used.
While flip chip technology has tremendous advantages over wire bonding and TAB, its cost and technical limitations are significant. For instance, the cost of forming bumps on the pads is significant. In addition, an adhesive is normally underfilled between the chip and the support circuit to reduce stress on the solder joints due to thermal mismatch between the chip and the support circuit, and the underfilling process increases both manufacturing complexity and cost. Furthermore, the solder joints exhibit increased electrical resistance as well as cracks and voids over time due to fatigue from thermo-mechanical stresses. Finally, the solder is typically a tin-lead alloy and lead-based materials are becoming far less popular due to environmental concerns over disposing of toxic materials and leaching of toxic materials into ground water supplies.
Other techniques besides wire bonding, TAB and flip-chip bonding have been developed to connect chips to external circuitry without using wires, leads or bumps. Such techniques include thin film rerouting at the wafer, panel or module level, and attaching a pre-patterned substrate to the chip such that through-holes in the substrate expose the pads and selectively applying conductive material into the through-holes. Several approaches are described below.
A typical thin film routing approach includes depositing a dielectric material on the chip, providing through-holes in the dielectric material that expose the pads, providing metallization in the through-holes that contacts the pads, and providing a top layer of conductive circuitry on the dielectric material that contacts the metallization. In this manner, the additional circuitry is fabricated on the chip. Drawbacks to this approach include complicated manufacturing requirements, high cost, and chip loss if the additional circuitry is defective. In particular, since the chip or wafer provides a substrate for the additional circuitry, chips will be lost if the additional circuitry fails to achieve certain quality and yield criteria. Unpredictable chip loss has prevented the wide spread adoption of this xe2x80x9cchip firstxe2x80x9d approach in volume production. Furthermore, if the process is not performed on wafers, the commercially available silicon wafer processing equipment may not be compatible with common tooling and handling techniques.
U.S. Pat. No. 5,407,864 discloses providing a partially assembled printed circuit board (PCB) with buried conductive traces and through-holes that expose portions of the conductive traces, attaching the PCB to the chip using an adhesive, removing portions of the adhesive exposed by the through-holes to expose the pads, depositing a blanket conductive layer over the PCB which covers the pads and sidewalls of the through-holes without filling the through-holes, depositing a blanket insulative layer over the PCB which fills the remaining space in tile through-holes, polishing the PCB to remove the conductive layer and the insulative layer from the top surface, and providing circuitry at the top surface that is connected to the conductive traces. In this manner, the circuitry at the top surface is connected to the pads through the conductive traces and portions of the conductive layer in the through-holes. Since, however, the conductive layer is blanket deposited over the entire PCB, polishing is used to remove the conductive layer from the top surface of the PCB since it would otherwise short the pads together. Polishing the conductive layer is costly and time consuming. Another drawback is that the polishing completely removes the top layer of the PCB, and therefore subsequent processes such as masking, circuitization and bumping are necessary for fabricating top surface circuitry such as traces and terminals for the next level assembly.
U.S. Pat. No. 6,037,665 discloses providing a chip with solder bumped pads, providing a pre-patterned multi-layer substrate with pre-metallized through-holes aligned with the pads, filling solder from the bumped pads into the through-holes, and reflowing the solder to form solder joint connections with the pads. This approach is similar to flip-chip bonding except that the solder is filled into the through-holes instead of merely being disposed between the chip and the substrate. Drawbacks to this approach include the need to solder bump the chip as well as the disadvantages of solder joints discussed above.
U.S. Pat. No. 5,116,463 discloses attaching a multi-layer substrate to a chip that includes forming through-holes through a dielectric layer that extend to the pads and electrolessly plating metal into the through-holes. The electroless plating is initiated by the pads and continues until the deposited metal fills the through-holes and contacts metallization on the top surface of the substrate. Drawbacks to this approach include the need for the metallization on the top surface to provide endpoint detection and the possibility that electroless plating on the metallization on the top surface adjacent to the top of the through-hole may close the through-hole before the electroless plating fills the through-hole.
U.S. Pat. No. 5,556,810 discloses inner leads laminated by an organic film and attached to a chip by an adhesive. Distal ends of the inner leads are positioned near the pads and then electrically connected to the pads by L-shaped plated metal. However, since the inner leads are flexible and vary in height and length, the inner leads may not be positioned precisely and uniformly, the gaps between the distal ends and the respective pads can vary, and consequently the plated metal joints may be weak or open. Furthermore, if the chip has moderate to high pad density and a separate power/ground plane is needed to achieve better electrical performance, the single layer inner leads may not be suitable. In addition, handling of this leaded-chip for the next level assembly such as outer lead bonding or board level assembly can be problematic since the leads are soft and easily bent, rendering it difficult to maintain co-planarity among the leads during the next level assembly.
Recent introduction of grid array packaging (e.g., ball grid arrays), chip size packages (CSP) and flip-chip packages using high density interconnect substrates are relentlessly driving increased printed circuit board density. Shrinking traces and spaces and increasing layer count increase printed circuit board density, however reducing the size of plated through-holes can even more significantly increase printed circuit board density. Small through-holes allow more routing space so that more conductive lines can be placed between the through-holes. Small throughholes also increase design flexibility and reduce design cycle time and overall product introduction time.
Conventional printed circuit boards have drilled through-holes with a size (diameter) in the range of 200 to 400 microns. As drilling technology improves, the drilled through-hole size is anticipated to reach 100 microns. Moreover, recently developed methods for forming through-holes using a punch, plasma or laser have driven down through-hole size to the range of 50 microns or less. A typical chip pad has a length and width on the order of 50 to 100 microns. Since the through-holes allow the pads to interconnect with various circuitry layers, using through-holes with similar sizes to the pads is desirable. The major advantage of using metallization in through-holes to interconnect the pads is that it replaces external media such as wires, bumps and leads.
The semiconductor chip assembly is subsequently connected to another circuit such as a PCB or mother board during next level assembly. Different semiconductor assemblies are connected to the next level assembly in different ways. For instance, ball grid array (BGA) packages contain an array of solder balls, and land grid array (LGA) packages contain an array of metal pads that receive corresponding solder traces on the PCB. However, since BGA and LGA packages are connected to the PCB by solder joints, the compliance is small and solder joint reliability problems exist. Plastic quad flat pack (PQFP) packages have a lead frame formed into a gull-wing shape. When the PQFP is assembled on a PCB, this gull-wing lead serves as the contact terminal which provides compliance and reduces stress on the solder joints. However, drawbacks to PQFP packages include the large size of the lead and poor high frequency electrical characteristics.
Thermo-mechanical wear or creep of the solder joints that connect the semiconductor chip assembly to the next level assembly is a major cause of failure in most board assemblies. This is because non-uniform thermal expansion and/or contraction of different materials causes mechanical stress on the solder joints.
Thermal mismatch induced solder joint stress can be reduced by using materials having a similar coefficient of thermal expansion (CTE). However, due to large transient temperature differences between the chip and other materials during power-up of the system, the induced solder joint stress makes the assembly unreliable even when the chip and the other materials have closely matched thermal expansion coefficients.
Thermal mismatch induced solder joint stress can also be reduced by proper design of the support circuit. For instance, BGA and LGA packages have been designed with pillar post type contact terminals that extend above the package and act as a stand-off or spacer between the package and the PCB in order to absorb thermal stress and reduce solder joint fatigue. The higher the aspect ratio of the pillar, the more easily the pillar can flex to follow expansion of the two ends and reduce shear stress.
Conventional approaches to forming the pillar either on a wafer or a separate support circuit include a bonded interconnect process (BIP) and plating using photoresist.
BIP forms a gold ball on a pad of the chip and a gold pin extending upwardly from the gold ball using a thermocompression wire bonder. Thereafter, the gold pin is brought in contact with a molten solder bump on a support circuit, and the solder is reflowed and cooled to form a solder joint around the gold pin. A drawback to this approach is that when the wire bonder forms the gold ball on the pad it applies substantial pressure to the pad which might destroy active circuitry beneath the pad. In addition, gold from the pin can dissolve into the solder to form a gold-tin intermetallic compound which mechanically weakens the pin and therefore reduces reliability.
U.S. Pat. No 5,722,162 discloses fabricating a pillar by electroplating the pillar on a selected portion of an underlying metal exposed by an opening in photoresist and then stripping the photoresist. Although it is convenient to use photoresist to define the location of the pillar, electroplating the pillar in an opening in the photoresist has certain drawbacks. First, the photoresist is selectively exposed to light that initiates a reaction in regions of the photoresist that correspond to the desired pattern. Since photoresist is not fully transparent and tends to absorb the light, the thicker the photoresist, the poorer the penetration efficiency of the light. As a result, the lower portion of the photoresist might not receive adequate light to initiate or complete the intended photo-reaction. Consequently, the bottom portion of the opening in the photoresist might be too narrow, causing a pillar formed in the narrowed opening to have a diameter that decreases with decreasing height. Such a pillar has a high risk of fracturing at its lower portion in response to thermally induced stress. Second, if the photoresist is relatively thick (such as 100 microns or more), the photoresist may need to be applied with multiple coatings and receive multiple light exposures and bakes, which increases cost and reduces yield. Third, if the photoresist is relatively thick, the electroplated pillar may be non-uniform due to poor current density distribution in the relatively deep opening. As a result, the pillar may have a jagged or pointed top surface instead of a flat top surface that is better suited for providing a contact terminal for the next level assembly.
In view of the various development stages and limitations in currently available support circuits for semiconductor chip assemblies, there is a need for a support circuit that is cost-effective, reliable, manufacturable, provides excellent mechanical and electrical performance, and complies with stringent environmental standards.
An object of the present invention is to provide a support circuit adapted for semiconductor chip assemblies such as chip size packages, ball grid arrays or other structures.
Another object of the present invention is to provide a convenient, costeffective method for manufacturing a support circuit for use in a low cost, high performance, high reliability package.
In accordance with one aspect of the invention, a method of manufacturing a support circuit includes providing a conductive layer with top and bottom surfaces, providing a top etch mask on the top surface that includes an opening that exposes a portion of the top surface, providing a bottom etch mask on the bottom surface that includes an opening that exposes a portion of the bottom surface, applying an etch to the exposed portion of the top surface through the opening in the top etch mask thereby etching partially but not completely through the conductive layer and forming a recessed portion in the conductive layer below the top surface, forming an insulative base on the recessed portion without forming the insulative base on the top surface, applying an etch to the exposed portion of the bottom surface through the opening in the bottom etch mask thereby forming a routing line in the recessed portion, applying an etch to the insulative base to form an opening in the insulative base that exposes a portion of the routing line, and applying an etch to the exposed portion of the routing line through the opening in the insulative base thereby forming an opening in the routing line with tapered sidewalls.
Preferably, the method includes applying the etch to the exposed portion of the top surface, then providing the insulative base, then applying the etch to the exposed portion of the bottom surface, then providing the opening in the insulative base, then applying the etch to the exposed portion of the routing line.
It is also preferred that the opening in the routing line has a diameter that increases with increasing height, the tapered sidewalls have a slope of about 45 to 75 degrees, the pillar extends above the routing line at least twice the distance that the insulative base extends above the routing line, and the pillar has a diameter that decreases with increasing height.
The method may include simultaneously forming the etch masks and then simultaneously stripping the etch masks after applying the etches to the exposed portions of the top and bottom surfaces.
The method may also include applying an etch that enlarges the opening in the base after forming the opening in the routing line, thereby exposing a portion of a top surface of the routing line adjacent to the tapered sidewalls and exposing an upper portion of the tapered sidewalls.
The method may further include covering the bottom surface with an adhesive and applying the etch that enlarges the opening in the base so as to at least partially form an opening in an adhesive below the opening in the routing line.
An advantage of the present invention is that the opening in the routing line with the tapered sidewalls is particularly well-suited to receive a ball bond connection joint applied by wire bonding that contacts both the tapered sidewalls and an underlying pad on a chip. Another advantage is that the pillar is formed using etching (i.e., subtractively) rather than by electroplating or electroless plating (i.e., additively) which improves uniformity and reduces manufacturing time and cost. Another advantage is that the support circuit can be manufactured using low temperature processes which reduces stress and improves reliability. A further advantage is that the support circuit can be manufactured using well-controlled wet chemical processes which can be easily implemented by circuit board, lead frame and tape manufacturers. Still another advantage is that the support circuit can be manufactured using materials that are compatible with copper chip and lead-free environmental requirements.
These and other objects, features and advantages of the invention will be further described and more readily apparent from a review of the detailed description of the preferred embodiments which follows. | {
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1. Field of the Invention
The present invention relates, in general, to metal making apparatus and, specifically, to molten metal receptacles and, more specifically, to a slag control shape loading device used in molten metal vessels.
2. Description of the Art
In metal making processes, such as steel making, molten metal is transferred from a furnace or converter by a ladle to a tundish or directly to a casting machine. In all metal making processes, and, in particular, in steel making processes, a layer of slag containing metal impurities forms above the top surface of the molten metal within the ladle and the tundish. When the molten metal is discharged from the ladle or tundish, it is necessary to maintain a separation between the slag and the molten metal so that high quality steel without significant amounts of slag can be produced.
The slag forms a layer of impurities several inches thick on top of the layer of molten metal in the ladle and in the tundish. In addition, the flow of molten metal through the discharge nozzle in the ladle or tundish creates a vortex which introduces a conically-shaped rotation to the molten metal immediately above the discharge nozzle. When a sufficient quantity of molten metal is maintained within the ladle or tundish, the vortex forms completely within the molten metal layer and does not reach to the slag layer atop the molten metal layer. However, when the level of molten metal within the ladle or tundish drops below the predetermined critical depth, the vortex reaches into the slag layer and draws slag through the center of the vortex to the discharge nozzle along with molten metal. This causes the introduction of slag into the molten metal as it is discharged from the ladle or the tundish and results in steel having less than desirable quantities as well as creating a potentially hazardous situation.
In order to prevent the introduction of slag into the molten metal, various slag control shapes, such as balls, frusto-conical bodies, etc., as shown in U.S. Pat. Nos. 4,725,045 and 4,968,007, are introduced into the transfer ladle or tundish. Such slag control shapes or bodies have a predetermined specific gravity less than the specific gravity of the molten metal and greater than the specific gravity of the slag layer so that the slag control shape or body is buoyantly supported at the interface between the slag layer and the molten metal layer. Such slag control bodies or shapes are also designed to locate and center themselves automatically in the vortex formed above the discharge nozzle from the molten metal vessel or receptacle. The lower portion of such slag control bodies is disposed in the molten metal layer and will enter and seat within the upper portion of the discharge nozzle of the molten metal receptacle when the molten metal layer drops below a predetermined depth so as to block the discharge nozzle and prevent the discharge of slag from the receptacle.
While such slag control bodies or shapes have found widespread use and effectively block the undesirable discharge of slag from a molten metal vessel, such as a transfer ladle or tundish, the introduction of such slag control bodies into the molten metal receptacle has proved to be a problem.
Typically, such slag control bodies are introduced into the transfer ladle or tundish at a predetermined time during the discharge of molten metal from the ladle or tundish. The time of insertion of the slag control body is based on an operator's experience, typically on the total time of molten metal discharge, or on a potentially inaccurate vessel or ladle weight reading from a load cell in a ladle weight system. As ladles positioned in caster turret arms are typically 20 feet or more in height, overhead cranes have been used to drop the slag control body into the ladle at the point in time indicated by an operator. However, such cranes are assigned numerous other tasks which make it difficult to insure that a crane is available at the precise time that the operator determines it necessary to insert the slag control body into the molten metal vessel.
A small number of metal making or casting machine installations have a stairway located adjacent the discharge position of a ladle which enables a worker, such as a ladleman, to climb to the top of the ladle and insert the slag control body into the ladle at the required time. However, the height of the ladle, the approximate 25 pounds or more weight of the slag control body, and the high temperatures involved in the molten metal process make such a task difficult, undesirable and dangerous. Further, the ladleman typically has other duties in monitoring the metal making process which must be neglected for the time it takes to climb the stairs and insert the slag control body. Dedicating one person solely to the task of inserting the slag control body into the molten metal vessel at the required time adds costs to the metal making process as such an individual is only required is to perform his single task at widely spaced, intermittent intervals.
Further, when such slag control shapes are dropped into a molten metal vessel, they typically fall from 10 to 15 feet before hitting the slag layer. Due to the buoyancy characteristics of a slag control shape and its momentum during dropping into the vessel, the slag control shape will initially pass through the slag layer and into the molten metal and then bob up out of the molten metal and slag until it settles at the molten metal/slag interface. However, this bobbing force and the inherent buoyancy characteristics of a slag control shape frequently cause the slag control shape to settle at a position away from a desired position directed above the discharge outlet of the molten metal vessel. Indeed, it is infrequent for the slag control shape to settle directly over the discharge outlet since the discharge outlet is typically 2½ to 4½ inches in diameter as compared to the 10 to 20 foot diameter of a typical ladle. Thus, when a vortex begins to form above the discharge outlet when the molten metal reaches a low level within the ladle or vessel, the slag control shape may not be able to reach the vortex in time to serve its function of blocking the outlet to prevent the discharge of slag through the outlet. Furthermore, even if the slag control shape initially settles directly over the discharge outlet, it frequently drifts away since a vortex may not have formed above the outlet and never returns to the desired centered position thereby defeating its intended purpose.
In order to address these problems, one of Applicants' previously devised a slag control shape release apparatus which is disclosed in U.S. Pat. No. 5,249,780 issued on Oct. 5, 1993. In this apparatus, the hanger of a slag control shape extends through a bore in a molten metal vessel cover and, also, through a bore in a lid pivotally mounted on the cover. A pin is mounted on the lid and biased to a position extending through the hanger to support the slag control shape on the cover. An actuating cable is connected to the pin and extends from the cover to an easily accessible position for remote actuation of the release mechanism to release the pin from the slag control shape and to allow the descent of the slag control shape into the molten metal vessel.
A similar release apparatus has also been devised by one of the Applicants and is disclosed in U.S. Pat. No. 5,303,902 issued on Apr. 19, 1994. In this apparatus, a mounting means including a reciprocally movable pin is mounted on a frame pivotally mounted on the cover of a molten metal vessel and is actuated by a cable extending from the pin to a free end remote from the cover. A cable wound around a reel mounted on the frame is attached to the slag control shape to control the descent of the slag control shape into the molten metal vessel after release from the pin.
Yet another release apparatus has been devised by one of the Applicants' and is disclosed in U.S. Pat. No. 5,423,522, which issued on Jun. 13, 1995. In this release apparatus, a lid is removably implacable in a bore in the cover. The hanger or rod of a slag control shape extends through the lid and is releasably received in mounting means on the lid. The actuating means is similar to that in the other release devices devised by the Applicants' in that it is in the form of a cable having an end operable from a location remote from the cover on the molten metal receptacle. In this latter design, means are provided for releasably connecting the actuating means to the mounting means after the mounting means and the lid have been mounted on the cover. This enables the heavy mounting and activating means to be mounted on the lid rather than on the cover which is typically formed of lightweight refractory or ceramic fiber materials.
In the slag control apparatus, also devised by one of the Applicants, and shown in U.S. Pat. No. 5,421,560, issued on Jun. 6, 1995, the mounting means of the slag control shape release apparatus includes a frame fixedly mounted on a lid and slidably supporting a tubular pin. The pin supports the hanger of the slag control shape at one end. A biasing means mounted on the frame normally biases the pin to a first position. The actuating means is releasably connected to the mounting means for actuating the mounting means to release the slag control shape. The actuating means is also operable from a location remote from the cover. In one embodiment, a weight control means determines the weight of the ladle indicate the amount of molten metal remaining in the receptacle. At an appropriate preset weight, a controller transmits a radio frequency signal to the actuating means to automatically release the slag control shape into the molten metal receptacle.
While all of these apparatus have proved effective at accurately dropping a slag control shape into a molten metal vessel and permitting the timely release of the slag control shape from an easily accessible location remote from the cover on top of a molten metal vessel, all except the latter release apparatus require the manual intervention of the ladleman or operator at the proper time to pull the cable to release the slag control shape from the cover. Despite the close location of the end of the cable connected to the actuating means in each of these release devices to the operator, the operator is still required to move at least a short distance to grasp and pull the cable. Thus, it would be desirable to provide a slag control shape release apparatus for use with a molten metal receptacle or vessel which enables an operator to release a slag control shape into the receptacle from a location more convenient or closer to the usual location of the operator or ladleman on the casting platform adjacent to the ladle. | {
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The invention relates to a distributed queuing system, such as a system providing timed delivery of messages.
Distributed message queue systems are currently available, including several commercial solutions such as IBM's Message Queue (MQ) Series and Microsoft's Message Queue Server (MSMQ). However, the existing systems invariably involve a centralized server or process for control of the queue. Therefore, there is a need for a system utilizing decentralized processes. | {
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1. Technical Field
The present invention relates to a bonding pad fabrication method, a method for fabricating a bonding pad and an electronic device, and an electronic device.
2. Related Art
In a semiconductor device, a semiconductor device (chip) and a bonding pad as an electrode pad, both disposed on a substrate, are connected by a bonding wire. The bonding wire is made of a conductive material, such as aluminum or gold, and establishes continuity between the semiconductor device (chip) and the bonding pad.
As described in an example below, the bonding pad is made of a conductive material, such as aluminum, and a thin film forming method is used because when forming a film, the method can easily control the thickness of the film.
JP-A-2005-167274 is an example of related art.
However, the method according to JP-A-2005-167274 requires more accurate mask alignment as the shape of the bonding pad becomes minuter. It is troublesome that each substrate requires mask alignment work. The flat bonding pad makes it difficult to apply force to the pad uniformly when bonding a wire to the pad. This may prevent the wire from being properly connected to the bonding pad. | {
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The invention concerns an apparatus for producing a honeycomb body, in particular a catalytic converter carrier body, having at least one stack of a plurality of at least partially structured metal sheets.
Carrier bodies for catalytic converters which provide for a reduction in the amount of pollutants in exhaust gases, in particular exhaust gases of an engine, can be in the form of a metallic honeycomb body. Such honeycomb bodies include a stack having a plurality of at least partially structured metal sheets. U.S. Pat. No. 4,923,109 describes a honeycomb body which has a stack of at least partially structured metal sheets, the stack being wrapped or twisted in opposite directions around itself and around a central region.
Published German Patent Application DE 195 21 685 A1 discloses a method for producing such a honeycomb body. In accordance with that method it is proposed that initially a stack is formed from a plurality of at least partially structured sheet metal layers. The stack is thereafter introduced into an open mould formed from mould segments corresponding to the outside shape of the honeycomb body to be produced, and the stack is held by a wrapping device in a central region. Thereupon the stack is wound or wrapped around in a direction of rotation and the mould is closed by pivoting the mould segments in the opposite direction to the direction of rotation of the wrapping device when a predetermined degree of wrapping is attained.
German Patent DE 195 22 327 discloses a method for producing a honeycomb body having a plurality of channels through which a fluid can flow. The honeycomb body has a plurality of at least partially structured sheet metal layers. This method is suitable in particular for producing a honeycomb body as is known from International Patent Application WO 90/03220. Such a honeycomb body has at least three stacks of metal sheets. At least three of the stacks are folded around a respective associated bend line in the central region of the honeycomb body and twisted in the folded condition in the same direction around each other and around the central region with the bend lines. Production of such a honeycomb body is effected in accordance with Published German Patent Application DE 195 22 327 A1 by virtue of each stack being folded about a respective bend line. The stacks when folded in that way are introduced into a mould. Each stack is held by a wrapping or twisting device in a central region. The wrapping or twisting device has winding bars which engage into the bent stack in the region of each bend line. The individual stacks are twisted in the same direction by rotation of the winding bars about a central axis.
International Patent Application WO 94/01661 discloses a honeycomb body which is made up of only a small number of metal sheets. The structure of the honeycomb body is suitable for at least one elongate electrical conductor to be integrated into at least one of the sheet metal layers or for one of the sheet metal layers itself to be in the form of an elongate insulated electrical conductor. For the production of such a metallic honeycomb body consisting of at least partially structured sheet metal layers, WO 94/01661 proposes that a hollow cone is produced from a small number of at least partially structured sheet metal strips. That hollow cone or circular ring is deformed from the outside inwardly at least at three lines so that a corresponding number of reversal lines are formed both in an outer region of the ring and also in an inner region thereof. The resulting star-like or rosette-like structure, which has loop configurations, is twisted by same-directional, rotational twisting of the loop configurations, which extend between the inner reversal lines and the outer reversal lines, about the inner reversal lines.
It has been found that defects, which adversely affect the quality of the honeycomb body, occur in some regions in the macrostructure of the finished honeycomb body. Such defects occur in an irregular fashion when successively producing a plurality of honeycomb bodies, which are manufactured using the same apparatuses. This requires particular measures in the quality control of the honeycomb bodies produced.
It is accordingly an object of the invention to provide an apparatus for producing a honeycomb body which overcomes the above-mentioned disadvantages of the heretofore-known methods of this general type and which improves the quality of the honeycomb body produced. A further object of the invention is to provide a method for producing a plurality of honeycomb bodies that simplifies quality assurance.
With the foregoing and other objects in view there is provided, in accordance with the invention, a method for producing a honeycomb body having a plurality of at least partially structured sheet metal layers and formed with a plurality of channels through which a fluid can pass. The method comprises the following steps:
a) forming a stack with a plurality of at least partially structured sheet metal layers defining channels and with a central region, the channels defining a longitudinal direction;
b) introducing the stack into a mould;
c) holding the stack in the mould with a wrapping device and with positioning elements reaching at least partially into the channels in the central region of the stack, the wrapping device being pivotable around a winding axis and having at least two winding bars located essentially parallel to the winding axis and extending along the longitudinal direction of the channels, the at least two winding bars engaging the stack at a respective exterior surface at the central region of the stack; and
d) wrapping the stack until a predetermined degree of wrapping of the stack is attained, while maintaining, in the central region of the stack, a structural configuration of structures disposed relative to one another and formed by the at least partially structured-sheet metal layers.
With the objects of the invention in view there is also provided a method for producing honeycomb bodies, each having a plurality of at least partially structured sheet metal layers and each formed with a plurality of channels through which a fluid can pass. The method which comprises the following steps:
a) forming a stack with a plurality of at least partially structured sheet metal layers defining channels and with a central region, the channels defining a longitudinal direction;
b) introducing the stack into a mould;
c) holding the stack in the mould with a wrapping device and with positioning elements reaching at least partially into the channels, in the central region of the stack, the wrapping device being pivotable around a winding axis and having at least two winding bars located essentially parallel to the winding axis and extending along the longitudinal direction of the channels, the at least two winding bars engaging the stack at a respective exterior surface at the central region of the stack; and
d) wrapping the stack until a predetermined degree of wrapping of the stack is attained for producing a honeycomb body;
e) removing the stack in its wrapped condition from the mould; and
f) repeating steps a) to e) with further stacks for producing further honeycomb bodies, the stack and each of the further stacks formed with the same structural configuration in the respective central region, the structural configuration having structures disposed relative to one another and formed by the at least partially structured sheet metal layers, and maintaining, during the wrapping step, the structural configuration of the at least partially structured sheet metal layers of each of the stacks.
In accordance with another mode of the invention, the structural configuration in the central region of the stack for the honeycomb body is determined after the step of forming the stack, and the further stacks are formed such that the structural configuration in the central region of the stack is repeated by layering further pluralities of at least partially structured sheet metal layers for the further honeycomb bodies, if the honeycomb body produced from the stack satisfies predetermined quality criteria.
With the objects of the invention in view there is further provided an apparatus for producing a honeycomb body from a stack having a plurality of at least partially structured sheet metal layers forming a plurality of channels through which a fluid can pass, comprising:
a mould having an internal shape substantially corresponding to an external shape of a honeycomb body to be produced;
a wrapping device for holding a stack at least partially structured sheet metal layers at a central region thereof, the wrapping device being pivotally disposed about an axis for wrapping the stack; and
a holding device having positioning elements at least partially insertable into channels formed in the central region of the stack for maintaining a structural configuration in the central region of the stack during a wrapping of the stack.
In accordance with the invention, a method is provided for producing a honeycomb body having a plurality of channels through which a fluid can flow. The honeycomb body comprises a plurality of at least partially structured metal sheets or sheet metal layers. According to the method, at least one stack is formed from a plurality of at least partially structured metal sheets. The stack is introduced into a mould and is held therein by a wrapping device rotatable about an axis in the central region of the stack. The stack, which has been introduced into the mould, is then subjected to a wrapping procedure until the stack has reached a predetermined degree of wrapping. At least during the wrapping procedure a structural configuration formed in a central region with structures of the metal sheets, which are disposed relative to one another, is maintained. The method thus ensures that no relative movement of the structures occurs in a central region of the stack, whereby it is possible to produce honeycomb bodies which are of consistent quality. Maintaining the structural configuration with structures of the metal sheets, which are disposed relative to each other, in the central region of the stack, is preferably effected as from formation of the structural configuration in the central region. In the case of honeycomb bodies known for example from Published German Patent Application DE 195 21 685 A1, the structural configuration is preferably maintained for the further steps in the method, with the termination of the operation of forming the stack of metal sheets. In the case of honeycomb bodies in which the stack is bent about a bend line, the macrostructure of the stack in the central region, that is to say in the region of the bend line, is considered as the structural configuration.
The structural configuration is preferably predetermined or designated in the central region of a stack. It is also possible to determine, on the basis of empirical investigations, a structural configuration in the central region of a stack, which results in honeycomb bodies which are particularly advantageous in terms of their quality.
It has already been stated above that honeycomb bodies may have defects in their macrostructure. Those defects involve deformation of channel walls which are formed by the at least partially structured metal sheets or sheet metal layers. Such deformations adjoin in particular regions in which the honeycomb body has a relatively stiff structure. To avoid deformation of the channel walls in the region of such stiff structures, it is proposed that a stack is layered alternately from structured metal sheets, which have corrugation crests and troughs, and smooth metal sheets, wherein the layering of the stack is effected in such a way that a corrugation crest of a structured metal sheet is disposed substantially between two corrugation troughs of an adjacent structured metal sheet. Such a stack involves a relatively low level of stiffness. Relative displacement of the structures of adjacent metal sheets occurs due to the operation of wrapping the stack or stacks. As a result, the cross-section of the honeycomb body has regions which can have a higher level of stiffness than the central region.
Those stiffer regions however are not so pronounced or stiff that in adjacent areas of those regions the assembly suffers from deformation of the structures which form the channel walls. Forming a stack with a relatively soft central region is particularly suitable for the production of honeycomb bodies of a small diameter or a small degree of wrapping.
To avoid relatively stiff regions in the cross-section of the honeycomb body it is sufficient if the structural configuration in the central region of a stack is relatively soft. It is also possible to construct a stack in such a way that the stiffness of the stack does not change in a direction transverse with respect to the longitudinal direction of the structures. For that purpose it is proposed that the structured metal sheets have corrugation crests and troughs which are repeated with a constant corrugation or wave length. With such a configuration of the structured sheets, it is proposed that the metal sheets, prior to the stacking operation, are severed from a metal sheet strip, wherein the sheets are of a length which corresponds to an integral multiple of the corrugation length. That operation of cutting the metal sheets to length provides that, when the structured metal sheets are put into a layered assembly to form a stack, a corrugation crest of a structured metal sheet is disposed substantially between two corrugation troughs of an adjacent structured sheet.
As an alternative to a stack having a structural configuration in the central region which is of a low level of stiffness, it is proposed that the structural configuration in the central region of the stack has a relatively high level of stiffness. A relatively high level of stiffness of the structural configuration in the central region of the stack is achieved with the structured metal sheets with corrugation crests and troughs and the smooth metal sheets being configured in an alternately layered layer assembly, such that that corrugation crests and troughs of adjacent structured metal sheets are aligned in a direction substantially perpendicular with respect to the longitudinal direction along which the corrugation crests or troughs, respectively, extend. If the structured metal sheets are such that the corrugation crests and troughs have a repeating corrugation or wave length, the layering array produces a stack which has a relatively high level of stiffness. The operation of wrapping around the stack causes relative displacement of the corrugation crests and troughs of the adjacent metal sheets. As a result, the corrugation crests are no longer disposed in alignment with respect to the corrugation troughs of adjacent metal sheets. Thus the finished honeycomb body has, outside the central region, as viewed in the radial direction, a structure with a lower level of stiffness than the central region. The central region of the finished honeycomb body can be considered as a relatively hard core and the region outside the core can be considered as a relatively soft shell. This mode of the invention allows producing a honeycomb body in which the formation of pronounced regions with a high level of strength in the shell is avoided.
If structured sheets which have corrugation crests and troughs that are repeated with a corrugation or wave length xcex are used to form the honeycomb body, it is proposed that the sheets, prior to the stacking operation, are severed from a sheet metal strip in a length corresponding to the relationship L=nxcex+0.5xcex wherein n is an element from the group of natural numbers. That ensures that in the operation of stacking the structured metal sheets corrugation crests and troughs of adjacent structured metal sheets are substantially aligned with each other.
In the production of a honeycomb body the length of the structured metal sheets cannot always be freely selected because the finished honeycomb body, as a catalytic converter carrier body, must have certain geometrical properties, for example a given number of channels in its cross-section. To form a defined structural configuration in the central region of the stack it is therefore proposed that positioning elements are introduced into the channels in the central region after forming a stack. A suitable form and configuration of the positioning elements with respect to each other makes it possible to produce a structural configuration in the central region of the stack, which has a relatively low or a relatively high level of stiffness. It is also possible to achieve suitable levels of stiffness of the stack in the central region, by suitably adapting the positioning elements to the required structural configuration of the central region.
In accordance with another mode of the invention, a method for producing honeycomb bodies with an improved quality is proposed, wherein each honeycomb body has a plurality of channels made of a plurality of at least partially structured metal sheets through which channels a fluid can flow.
In accordance with this method for the production of honeycomb bodies it is proposed that at least one stack is formed from a plurality of at least partially structured metal sheets. The layered stack is introduced into a mould and held therein by a wrapping device rotatable about an axis in the central region of the stack. The stack is subjected to a wrapping procedure until a predetermined degree of wrapping of the stack is achieved. The stack when wrapped in that way is removed from the mould, possibly after a fixing operation, for example through the us a tubular casing.
Those method steps are repeated for each stack of a further honeycomb body. Each stack is formed with a structural configuration which is always the same in a central region. The structural configuration has structures of the metal sheets, which structures are disposed relative to one another. That structural configuration is maintained at least during the wrapping procedure for each stack. The fact that the structural configuration of the structures of the metal sheets, which are disposed relative to each other, in the central region of the stack is the same in the case of each honeycomb body ensures that the distribution of the channels over the cross-section of the honeycomb body is almost the same in a plurality of honeycomb bodies. Preferably the structural configuration in the central region of a stack is predetermined for a first honeycomb body of a plurality of honeycomb bodies. The predetermined structural configuration in the central region is preferably so selected that within the cross-section of the honeycomb body there are no pronounced regions with a high level of stiffness generated, in the proximity of which deformed structures are formed.
A further mode of the invention provides that a stack for a first honeycomb body of a plurality of honeycomb bodies is formed in a layered configuration and the structural configuration in the central region of the stack is determined for the first honeycomb body. That structural configuration of the first stack in the central region is repeated by suitably layering metal sheets to form stacks for each further honeycomb body if the honeycomb body produced from the first stack satisfies predetermined quality criteria.
With the objects of the invention in view there is further provided an apparatus for producing at least one honeycomb body, in particular a catalytic converter honeycomb body, made from at least one stack having a plurality of at least partially structured metal sheets which form a plurality of channels through which a fluid can flow. The apparatus includes a mould, the internal configuration of which substantially corresponds to an external shape of a honeycomb body to be produced. The apparatus also includes a wrapping device by which each stack is held in its central region at least during a wrapping procedure. The wrapping device has a holding device by which each stack is held in the central region of the stack in such a way that a structural configuration produced in a central region with structures of the metal sheets, which are disposed relative to one another, is maintained at least during the wrapping procedure.
Advantageously the holding device has positioning elements which can be at least partially introduced into the channels of the structural configuration in a central region of each stack. The configuration of the positioning elements substantially corresponds to the shape of the channels. The positioning elements are preferably bar-shaped or have the shape of a mandrel. The width of the holding device is preferably such that it corresponds to the thickness of a stack.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in an apparatus for producing a honeycomb body, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. | {
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Underground conduits are widely used for the transmission of fluids, such as in pipelines and the like, as well as for carrying wires and cables for the transmission of electrical power and electrical communication signals. While the installation of such conduits is time-consuming and costly for locations where the earth can be excavated from the surface, the routing of such conduits becomes more difficult where such surface excavation cannot be done due to the presence of surface obstacles through which the excavation cannot easily proceed. Such surface obstacles include highways and railroads, where the installation of a crossing conduit would require the shutdown of traffic during the excavation and installation. Such surface obstacles also include rivers, which present extremely difficult problems for installing a crossing conduit, due to their size and the difficulty of excavation thereunder.
Prior methods for the installation of conduit have included the use of directional drilling for the formation of an inverted underground arcuate path extending between two surface locations and under the surface obstacle, with the conduit installed along the drilled path. A conventional and useful method for installing such underground conduits is disclosed in U.S. Pat. No. 4,679,637, issued July 14, 1987, assigned to Cherrington Corporation, and incorporated herein by this reference. This patent discloses a method for forming an enlarged arcuate bore and installing a conduit therein, beginning with the directional drilling of a pilot hole between the surface locations and under a surface obstacle such as a river. Following the drilling of the pilot hole, a reamer is pulled with the pilot drill string from the exit opening toward the entry opening, in order to enlarge the pilot hole to a size which will accept the conduit, or production casing in the case of a pipeline conduit. The conduit may be installed during the reaming operation, by the connection of a swivel behind the reamer and the connection of the conduit to the swivel, so that the conduit is installed as the reaming of the hole is performed. Alternatively, the conduit can be installed in a separate operation, following the reaming of the pilot hole (such reaming referred to as "pre-reaming" of the hole). Additional examples of the reaming operation, both as pre-reaming and in conjunction with the simultaneous installation of the product conduit, are described in U.S. Pat. No. 4,784,230, issued Nov. 15, 1988, assigned to Cherrington Corporation and incorporated by this reference.
While the above-described methods are generally successful in the installation of such conduit, certain problems have been observed, especially as the length of the conduit exceeds one mile in length, and especially where certain types of sub-surface formations are encountered. Referring now to FIGS. 1 and 2, examples of such problems in the installation of conduit in an underground arcuate path will now be described.
FIG. 1 illustrates the reaming operation described above, in conjunction with the installation of production conduit as the reamer is pulled back. In the example of FIG. 1, entry opening O is at surface S on one side of river R; exit opening E is on the other side of river R from entry opening O. At the point in the installation process illustrated in FIG. 1, a drilling apparatus, including a hydraulic motor 114 mounted on a carriage 116 which is in place on an inclined ramp 112, has drilled the pilot borehole B from entry O to exit E, using drill string 110, and the reaming and installation is in progress. Motor 114 is now pulling reamer 48, to which production conduit 46 is mounted, back from exit E toward entry O. Reamer 48 is larger in diameter than the diameter of production conduit 46. Upon completion of the reaming operation of FIG. 1, if successful, production conduit 46 will be in place under river R, and extending between exit E and entry O.
Referring now to FIG. 2, a close-up view of the location of reamer 48 and production conduit 46 in FIG. 1 is now illustrated. Leading drill string section 110C is attached by way of tool joint 52 to reamer 48, reamer 48 having cutting teeth at its face. Swivel 50 connects product conduit 46 to reamer 48, by way of extension 62 connected to a sleeve 66 on conduit 46. As is evident from FIGS. 1 and 2, borehole B is enlarged to enlarged opening D by operation of reamer 48. Conventional sizes of conduit 46 are on the order of 20 to 48 inches in outside diameter, with the size of reamer 48 greater in diameter than conduit 46. Due to reamer 48 being larger than conduit 46, an annulus 68 surrounds conduit 46 as it is pulled into the hole D. Provision of the annulus 68 allows for reduced friction as the conduit 46 is placed therein.
As noted above, prior techniques have also included a pre-reaming step, wherein a reamer such as reamer 48 is pulled back from exit E to entry 0 without also pulling production conduit 46 into the reamed hole. In such a pre-reaming step, a following pipe generally trails reamer 48 in such the same manner as conduit 46 trails reamer 48 in FIGS. 1 and 2, to provide a string for later installation of conduit 46. Such a trailing pipe will be of a much smaller size than conduit 46 of FIGS. 1 and 2, for example on the order of five to ten inches in diameter.
It has been observed in the field that both the pre-reaming and reaming with installation operations are subject to conduit or pipe sticking problems, especially as the size of the production conduit increases in diameter, and as the length of the path from entry O to exit E increases. Such sticking is believed to be due, in large degree, to the inability to remove cuttings resulting from the reaming operation. Due to the large volume of earth which is cut by way of the reaming operation, and the generally low fluid flow velocity of drilling or lubricating mud or fluid into the reaming location, the velocity of cuttings circulating from the reaming location is minimal. While the mud or other lubricating fluid flow could be increased in order to increase the velocity of the cuttings from the reaming location, such an increase in the velocity of the fluid could result in such undesired results as hole wall erosion and fracturing through the formation.
Due to the inability to sufficiently remove the cuttings during the reaming operation, it is believed that the cuttings pack together near the location of the reamer. Many of the cuttings from the reaming operation are heavier than the fluid transporting them and, in such large diameter holes as are required for the installation of conduit, these large cuttings will fall out or settle toward the bottom of the hole first, and then build up into a circumferential packed mass, especially when the rate of reaming is poor, as will be described hereinbelow. Referring to FIG. 2, where a production conduit 46 is being pulled through with reamer 48, it is believed that such packing will begin at locations P surrounding the leading end of conduit 46, and also along the sides of conduit 46 in annulus 68. As the cuttings pack together, squeezing out whatever water or fluid is present therein, the density of the packed mass increases. Upon sufficient packing, it is believed that pressure builds up ahead of locations P, toward the bit of reamer 48, such pressure resulting from the mud or fluid continuing to be pumped into the reaming location with the return flow reduced at locations P around conduit 46 in annulus 68. It is also believed that this buildup of pressure will also force cuttings into borehole B ahead of reamer 48, and that these cuttings will also begin to pack, most likely at locations P' near the first tool joint 70 ahead of reamer 48.
The buildup of pressure between locations P and P' surrounding reamer 48 causes significant problems in the reaming operation. Such effects have been observed in the field during reaming operations, when the reamer cannot be rotated, pulled or pushed at a particular location in the operation. It should be noted that the sticking of the reamer occurs both for the pre-reaming operation described hereinabove and for the combined reaming and pulling operation. It should further be noted that the pressure buildup described hereinabove is believed to be worse in high pressure formations such as clay.
Another undesired effect resulting from the buildup of pressure when the reamer cuttings are insufficiently removed is similar in nature to differential sticking in the downhole drilling field. As is well known in the downhole drilling art, differential sticking of the drill string occurs when the pressure of the drilling mud surrounding the drill string is greater than the pressure exerted by the surrounding formation. In the event that the caking of drilling mud and the structure of the well bore is not strong enough to maintain its shape when presented with such a differential pressure, the pressure of the drilling mud can force the drill string into the formation, holding it there with sufficient pressure that it cannot be released from the surface.
It is now believed that similar effects can be present in the field of installation of underground conduit, due to insufficient removal of the reaming cuttings. If the pressure near reamer 48, when packed off as described hereinabove, is sufficiently greater than the pressure exerted by a surrounding formation, the conduit 46 can be driven into the formation, causing sticking of the conduit 46 thereat. It should be noted that the installation of underground conduit is particularly susceptible to such sticking, since much of the formations underlying rivers are sedimentary or alluvial formations, with relatively thin layers of differing strength. Accordingly, the drilling and reaming operations in river crossing installations are exposed to many differing formations along the length of the path, with the likelihood of encountering a weak (in pressure) formation being relatively large. Accordingly, such pressure buildup due to insufficient reaming cutting removal can cause conduit sticking at particular locations along the underground path.
Furthermore, it should be noted that the insufficient removal of cuttings impacts the reaming operation itself. If cuttings are not sufficiently removed from the reaming location, a number of cuttings will tend to be present in front of reamer 48 of FIG. 2; as a result, reamer 48 will tend to recut its own cuttings, rather than cutting the earth in its path and enlarging the hole. This results in poor penetration rates for the reaming operation. As noted above, as the reaming rate slows, the pressure buildup between the packed locations will accelerate, further degrading the operation and increasing the likelihood of the reamer and conduit sticking. In addition, the recutting of the cuttings results in a high degree of reamer wear, both at the teeth and also in the parent metal of reamer 48. In rotor reamers, such wear has been observed also at the seals and bearings. This has also been observed for reamers which use carbide-coated rotating cones as the cutting bits, in similar manner as a downhole tri-cone bit; while the carbide wears slowly, the insufficient removal of the cuttings has been evidence in significant wear of the parent metal of the reamer.
Other methods for installing conduit in an underground path includes forward thrust techniques, such as described in U.S. Pat. Nos. 4,176,985, 4,221,503 and 4,121,673. Particularly, U.S. Pat. No. 4,176,985 discloses an apparatus which thrusts a casing into a pilot hole, with a bit leading the casing. However, while such forward thrust techniques are useful for unidirectional application such as the introduction of conduits into the ocean, such methods place significant stress on the conduit itself, and also present relatively slow installation rates. The pull-back methods described hereinabove and hereinbelow are preferable from the standpoint of reduced stress on the casing, as well as increased installation rates.
It is therefore an object to provide a method and apparatus of removing cuttings from the reaming operation in a method of installing underground conduit.
It is a further object of this invention to provide such a method and apparatus which is useful in a pre-reaming operation.
It is a further object of this invention to provide such a method and apparatus which is useful in an operation where the conduit is installed during the reaming operation.
It is a further object of this invention to provide such a method and apparatus which provides control of the pressure at the reaming location.
It is a further object of this invention to provide such a method and apparatus which includes agitation of the cuttings so that packing of the cuttings does not occur during a standstill in the reaming operation.
It is a further object of this invention to provide such a method and apparatus which provides a fluid return from the reamer which may easily be cleaned out in the event the return backs up.
It is a further object of this invention to provide such a method and apparatus which includes the solids control and pumping on the same side of the surface obstacle.
Other objects and advantages of the invention will be apparent to those of ordinary skill in the art having reference to the following specification, together with its drawings. | {
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The present invention relates generally to medical dispensing devices and, more particularly, to a recyclable dispensing device that permits selectively measured dosages of a liquid to be dispensed.
Patients suffering from diseases such as diabetes must inject themselves several times each day with an insulin solution. Since the volume of insulin solution to be injected varies from injection to injection, it is necessary for such patients to be able to measure a precise volume of insulin. Diabetics have conventionally used a syringe for injection of insulin. However, it is difficult to control the operation of the syringe as well as the quantity of drug injected.
In order to permit a diabetic to measure and administer a more accurate and controlled dosage, injector pens have been developed which enable a particular dosage to be accurately and conveniently measured. Generally, these pens are secured onto a cartridge having a particular quantity of liquid medication sealed therein. The cartridge includes a plunger and a mechanism for advancing the plunger in the cartridge in such a manner to dispense the medication. Injector pens may be reusable or disposable. In reusable pens, a user can change a spent cartridge and reset the leadscrew of the pen back to its initial position. In a disposable pen, the cartridge is permanently captured in the pen which is disposed of after the contents of the cartridge have been exhausted.
One such disposable pen that has functioned very adequately is disclosed in U.S. Pat. No. 5,295,976. Specifically, a dispensing device is disclosed and includes an internally threaded collar and an externally threaded plunger rod. In order to set a dosage of medication to be delivered, the collar is rotated thereby causing displacement of the collar toward the proximal end of the injection device. Rotation of the collar causes the integral cap to become effectively displaced both rotationally and axially toward the proximal end of the pen. As this displacement occurs, the segment of the dose-indicating scale which is visible through a window varies showing a linear increase in the number to indicate an increase dosage of liquid to be dispensed. Once the desired dosage is selected, a force is applied to the end of the cap causing a linear displacement of the cap, integral plunger rod, and piston to dispense liquid from the container. The dispensing displacement of the plunger rod is halted by abutting contact between the cap and a stop element.
In U.S. Pat. No. 5,308,340, another recyclable injection device is disclosed. In particular, a plunger rod is received within the housing for exerting a force on a piston closing a second end of the container. The plunger rod has a noncylindrical cross section with a first surface including threads and a second surface which can, optionally, include a series of ratchet teeth. A collar is received within the housing adjacent the second end of the container for permanently retaining the container of liquid within the housing. The plunger rod passes through the noncylindrical opening in the collar and is prevented from rotating with respect to the housing by the collar. A hollow cap envelopes the plunger rod opposite the container of liquid. The skirt of the hollow cap extends inside the housing. The cap includes a threaded interior surface which movably engages the plunger rod for calibrated adjustment relative thereto. A stop is provided within the housing, and a distal facing surface is provided on the hollow cap for contacting the stop upon linear movement of the cap and plunger rod as a unit toward the container to dispense liquid therefrom. In operation, the cap is rotated in a counterclockwise direction causing the threads of the cap to travel along the threaded portion of the rod. This rotation does not cause displacement of the plunger rod with respect to the housing, but backs the distal end of the proximal cap portion away from a stop shoulder on the inside of the housing. When the cap has been positioned to the desired dosage, pressure is applied to the end of the cap for causing it to move linearly toward the distal end of the housing until a shoulder defined by a radially exposed portion of the distal end contacts a stop. | {
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This invention concerns thermoformed products, and in particular open-topped plastic containers such as plant pots, formed with a rim which is slitted to receive a display insert.
Bedding plants are usually sold in rimmed pots or trays, and in the past, small display inserts printed with information such as the name of the plant, type, etc. were stuck into the soil in the pots. Such inserts were easily dislodged, removed, or switched to other containers by customers.
A display insert has been heretofore developed which is placed into a slit in the container rim with a locking action created by a barbed shape preventing removal.
In the thermoforming process, portions of a preheated plastic sheet material is stretched into a mold cavity in a tooling die, using plug assists and differential fluid pressure in a well known manner.
The containers so formed are subsequently cut free from the rest of the sheet in a trim station, using trim dies.
The regions surrounding portions of the sheet material to be formed into the container are clamped with clamping rings associated with each container mold cavity. A plug assist for each mold cavity is advanced into the sheet material to pre-stretch the material prior to application of the fluid pressure which is thereby applied to cause the material to be drawn into intimate contact with the mold cavities.
A through slot could possibly be molded to the rim during the thermoforming process by a mold feature, but this approach increases tooling costs since a special tooling feature must be provided for each cavity and a large number of cavities are typically employed, i.e., 24 or more cavities is typical for this type of product. Further more the need to mold in such a feature complicates the thermoforming process since only minimal space available in that area of the tooling.
Punching slots into the relatively thick rim after forming the containers requires a delicate punch and die set, prone to failure and also increasing the tooling costs.
More importantly, separate slugs would be produced by a punching process, and removing these slugs from the tooling is typically difficult. The presence of slugs which are not removed can create jams and other problems. Even if removed, disposal of the slugs is another burden.
As noted, the rim of the containers so formed is thicker than the body wall since a portion of the sheet material is stretched out during forming of the body while the rim is formed without stretching. This thick rim material is difficult to cut and thin knife blades will break easily if slitting is done in the trimming operation, to thus require a punch and die set.
Once slits are formed in the rim, the relatively thin plastic inserts are difficult to insert into a slit, particularly through an arcuate slit in the thick rim of a round container. If a punched out slot is formed to allow easier insertion, the expensive and delicate punch and die sets would be required. Also, slugs are formed creating problems as described above.
Furthermore, a high tonnage trim press would be required to perform the punching process, particularly when other steps are required to be done at the same time, such as to punch out bottom holes in the body portion.
It is the object of the present invention to provide an improved method and tooling to produce a thermoformed open-topped container having one or more slits in the rim thereof.
It is a further object to provide a thermoformed open topped product with slitted rim configuration which allows easy installation of a display insert into a slit in the rim. | {
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Field of the Disclosure
Embodiments of the present disclosure relates to the art of a power transmission unit for delivering torque of a prime mover to drive wheels, and especially to a power transmission unit having a torque limiter for preventing the prime mover and the power transmission unit from being subjected to an overload.
Discussion of the Related Art
JP-A-2009-120043 describes a drive unit for a hybrid vehicle having an engine, a first motor and a second motor, and a single-pinion planetary gear unit for distributing torque of the first motor to the engine and to the drive wheels. According to the teachings of JP-A-2009-120043, in the planetary gear unit, a carrier is connected to the engine, a sun gear is connected to the first motor, and a ring gear is connected to an output member for delivering power to the drive wheels. In the drive unit taught by JP-A-2009-120043, an operating mode can be selected from an electric mode in which the vehicle is powered at least by one of the first motor and the second motor while stopping the engine, a regeneration mode in which at least one of the first motor and the second motor is operated as a generator, and an engine mode in which the vehicle is powered by the engine. In order to halt a rotation of the engine during propulsion under the electric mode, the drive unit taught by JP-A-2009-120043 is provided with a dog clutch serving as a locking device in a casing holding the motors and the planetary gear unit.
US2015/0040720 A1 describes a vehicular transmission including a transmission input shaft to which engine torque is input, and a torque limiter arranged between the transmission input shaft and an engine. According to the teachings of US2015/0040720 A1, the torque limiter is configured to enable torque transmission between the transmission input shaft and an engine output shaft, and to inhibit an input of excessive torque larger than predetermined torque between the transmission input shaft and the engine output shaft. The vehicular transmission taught by US2015/0040720 is also used in a hybrid vehicle having an engine and two motors, and further provided with a one-way clutch serving as a locking device to prohibit reverse rotation of the engine while allowing normal rotation of the engine. The one-way clutch is fixed to a flywheel connected to an output shaft of the engine between the engine and a transmission, and the torque limiter and a damper device are also fixed to the flywheel outside of a transmission casing.
According to the teachings of JP-A-2009-120043, a drag loss of the engine can be reduced by halting (i.e., locking) a rotation of the engine by the locking device during propulsion under the electric mode. In addition, during propelling the vehicle by both motors, an output torque of the first motor can be delivered efficiently to the output member through the planetary gear unit by halting a rotation of the carrier together with the engine. In the drive unit taught by JP-A-2009-120043, a powertrain between the engine and the drive wheels can be prevented from being subjected to an excessive torque by arranging the torque limiter taught by US2015/0040720 in the powertrain. However, if the locking device is actuated during propulsion under the electric mode, the torque limiter may not function in the powertrain. In this situation, if an excessive disturbance torque is applied from the drive wheel, gears and shafts of the powertrain between the drive wheels and the locking device may be subjected to an excessive load. | {
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1. Field of the Invention
The invention relates to pallet jacks. More particularly, the invention relates to a system and method for operating and transporting a pallet jack loaded with packaged goods, wherein the packaged goods comprise consumer goods and/or raw materials for manufacturing, and wherein the pallet jack can be transported from a lower non-smooth surface to an upper surface, and further wherein the pallet jack can carry two pallets, side-by-side, and can place a first pallet at a first location separately from a second pallet without lowering the tines to disengage the second pallet.
2. Background Art
Manually operated pallet jacks are mechanical devices used primarily for interior applications in such locations as warehouses and some larger consumer stores. The term “manually” refers to the means for moving and operating the pallets jacks: typically, they use hydraulic, pneumatic or electric lifting mechanisms that an operator enables to lift goods. Pallet jacks typically have two or more tines or forks, that are placed under a pallet, upon which is stored the goods to be moved. In the U.S., loaded pallets are typically about 4 feet long by 4 feet wide, and can be between a couple of inches to as much as 8-10 feet in height. The major considerations in the maximum height are the weight to be lifted and the center of gravity.
Other types of pallet jacks include those that are completely or semi-automated. These pallet jacks can include an internal combustion engine or motor, or an electric or propane operated motor that drives the pallet jack according to mechanical inputs received from the operator. Some of these pallet jacks can place goods on pallet several stories in height (20′-40′).
As briefly discussed above, pallet jacks are usually operated in the interior of buildings, on substantially smooth, pre-stressed concrete floors. These floors are extremely smooth and extremely strong. Pallet jacks are generally designed to operate in such an interior environment, and usually have two small wheels located in the rear portion of the pallet jack, directly under the lifting mechanism. The tines, or forks, are located outwardly from the centrally located rear wheels (see FIG. 1 as an example of prior art pallet jack), and the lifting mechanism is located directly over the centrally located rear wheels. Such known pallet jacks are generally useful for lifting heavily loaded pallets, wherein the pallets have a length (measured in the same direction as the tines extend from the pallet jack) to width ratio of about 1.0 and less. That is, the prior art pallet jacks generally are used to lift pallets in which the width is usually the same or greater than the length. That is the most stable lifting configuration for these prior art pallet jacks.
As can be seen in the typical prior art pallet jack, the front and centrally located rear wheels are designed to be used on the substantially smooth surfaces inside warehouses on the pre-stressed concrete floors. Using these types of pallet jacks outside, on the rough terrain of a gravel parking lot would be ineffective at best, and possibly dangerous because of their instability in that type of environment. Furthermore, if the dimensions of the pallet the pallet jack were carrying was such that its width exceeds the width of the tines, and the pallet's length was longer than that of the tines, then again the pallet jack could be dangerous to operate. Further still, using the prior art jack as shown in FIG. 1 inside a retail environment, such as a convenience store, could scuff the polished floors because of the type of wheels that are typically used.
FIG. 2 illustrates a second type of device for carrying goods inside a retail environment. As can be seen, however, these types of devices lack any type of lifting mechanism, the rear wheels that pivot are too small for rough terrain (such as gravel parking lots) and the amount of goods they can lift are limited by structural limitations of the device. Furthermore, to use such a device shown in FIG. 2, a user will have to load each item and then unload each item. This type of repetitious activity can lead to repetitive motion injuries, accidents and thus increases costs for the manufacturer/distributor of the goods/products delivered by the device.
Thus, a need exists for a pallet jack that can operate on both non-smooth exterior and smooth interior surfaces with substantial ease, and that can also carry a significant amount of goods using differently shaped pallets, wherein the length to width ratios are about 2:1, 3:1 or even more. | {
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It is often desirable to accurately measure the distance between two objects. It becomes increasingly difficult to measure the distance between two objects when the distance that separates the objects is small, e.g., nanoscale spacing between two objects. A specific example of such a distance that is difficult to measure is the “fly height” between a slider and a disc positioned adjacent thereto. Such slider/disc arrangements are commonly used, for example, in data storage systems. Increased storage density is becoming increasingly important and a reduced fly height allows information to be stored in a smaller area, i.e., at a higher areal density. As fly height dimensions continue to decrease to support increased storage densities, it is important to be able to accurately measure the fly height in order to ensure that the data storage system is operating as designed. | {
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The pest control industry has changed dramatically over the last decade. One of these marked changes involves a reduction of the use of chemicals in homes, schools and the workplace in ridding them of pests. Health and well-being has seemed to take center stage in today's society. One of the latest trends regards the consumption of organic foods, so it seems rather counterproductive to employ chemicals in order to eliminate vermin.
Rats, mice and other rodents are indeed persistent problems in almost all areas of the world. In order to control such pests, people have resorted to various methods, including pesticides, to eradicate them. One of the most traditional methods of rodent elimination is now perhaps one that is most in keeping with the latest trends—a trap. In a typical configuration, a spring-loaded bar is held in place with a hair touch trigger typically loaded with bait such as cheese or other types of food. When the rodent attempts to move the bait, the trigger releases the spring which instantly swings the bar around and down upon the rodent thus trapping or killing it. While it is mostly effective, sometimes the bar does miss the rodent, due to the rodent's speed or position. In most cases a wider bar would be of assistance, but the increased weight would slow the movement of the bar down even more.
Accordingly, there exists a need for a means by which the trapping efficiency of a rat or mouse trap can be increased. The development of the “Z”-Bar Rodent Trap fulfills this need.
U.S. Pat. No. 7,162,832 issued to Simpson and Price discloses a rodent snap trap device. This patent does not appear to disclose a device that possesses a zig-zag configured trap bar to increase efficiency of the device.
U.S. Pat. No. 6,655,077 issued to Trevino discloses a trap for a mouse. This patent does not appear to disclose a device that possesses a zig-zag configured trap bar to provide increased efficacy of the device.
U.S. Pat. No. 6,415,544 issued to Leyerle discloses a rodent trap with entrapping teeth. This patent does not appear to disclose a device that possesses a zig-zag configured trap bar to provide increased efficiency of the device.
U.S. Pat. No. 5,375,367 issued to Pust discloses a mousetrap with deep bait receptacle. This patent does not appear to disclose a device that possesses a zig-zag configured trap bar.
U.S. Pat. No. 4,245,423 issued to Sousa and Bumstead discloses an animal trap. This patent does not appear to disclose a device with a zig-zag configured trap bar for increased efficiency.
U.S. Pat. No. 2,724,209 issued to Cain discloses an animal trap. This patent does not appear to disclose a device that possesses a zig-zag configuration on the trap bar and this device does not appear to possess the trap bar range of motion of the instant invention.
The prior art appears to disclose various tools for trapping rodents and animals. The prior art does not appear to disclose a rodent trap with a zig-zag configured trap bar for maximizing trapping efficiency. | {
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This invention relates to a nonvolatile semiconductor memory device.
EPROMs including floating gate MOS FETs as memory cells are generally used as nonvolatile semiconductor memories. Data are written into the EPROM through the effect of injection of the electrons into the floating gate. These electrons which are separated from holes by impact ionization in a pinch-off region formed in the vicinity of the drain when a high voltage is applied to the drain and control gate of a floating gate MOS FET. FIG. 1 shows an example of a prior art EPROM. The output signal of a memory array 2 formed of floating gate MOS FETs 1 is supplied to an input terminal of a differential sense amplifier 4, while the output signal of a reference signal generator 6, including floating gate MOS FETs 5 with the same configuration of the MOS FETs 1 forming the memory array 2, is supplied to the other input terminal of the differential sense amplifier 4. A gate signal generator 8 is connected to the control gate of the MOS FETs 5 in the reference signal generator 6. The output signal of the differential sense amplifier 4 is read out by means of an output buffer (not shown), and used as data.
At the time of reading, a specified memory cell in the memory array 2 is selected. The state of conduction of the memory cell depends on whether or not the floating gate is injected with electrons. Thus, the output line of the memory array 2 is charged or discharged. The output level of the sense amplifier 4 depends on the difference between the level of the output line of the memory array 2 and the output level of the reference signal generator 6. If the output voltages of the memory array 2 and the reference signal generator 6 are VA and VB, respectively, the output level of the sense amplifier 4 is logic 1 level where VA.degree.VB, and logic 0 level where VA<VB. If the gate voltage of the transistor 5 in the reference signal generator 6, i.e. the output voltage of the gate signal generator 8, is VR, VB is equal to VA corresponding to the gate voltage of the selected memory cell at VR when the memory cell is neutral, that is, when the floating gate is not injected with electrons.
If VR=0.6 VC is given by resistors between VC and VS in the gate signal generator 8, the gate potential of the selected memory cell is substantially equal to VC. If a neutral cell is selected, the relationship of VA<VB is established, so that the output level of the sense amplifier 4 becomes logic 0. If a written cell is selected, on the other hand, the relationship of VA>VB is established, so that the output level of the sense amplifier 4 becomes logic 1.
In order to check up the amount of data written in the memory cell, there will be investigated the minimum value of the threshold voltage of the memory cell whereby it is given as a conclusion that data is written in the memory cell. Since the MOS FET 5 for generating the reference signal is equivalent to the MOS FET 1 of the memory cell, a current flowing through both these MOS FETs is in proportion to the difference between the gate voltage and the threshold voltage. VA.degree.VB may be obtained under the following condition: EQU VC-VTH<VR-VTH' (1)
Here VTH and VTH' are the threshold voltages of the MOS FETs 1 and 5, respectively.
Substituting VR=0.6 VC into Expression (1), we obtain the following condition: EQU VTH.degree.0.4 VC+VTH' (2)
If VC=5.5 V and VTH'=1.5 V are given, the threshold voltage VTH of the memory cell is more than 3.7 V. Namely, data may be written in the memory cell at a voltage higher than 3.7 V as compared with the supply voltage of 5.5 V even if the MOS FET in the memory cell is not perfectly cutoff due to the electrons injected into the floating gate.
It is important, to check the memory cells of the EPROM for acceptablity, e.g. data holding capability before shipment. In a general test on an EPROM, the product is exposed to a high temperature after data is written, and then the threshold voltage VTH of the memory cell is detected. For this purpose, the supply voltage VC, i.e. the gate voltage of the memory cell, is changed, and a supply voltage VC' for the inversion of the state of the memory cell is detected. Suppose when the supply voltage VC' of the memory cell is 7 V, the memory data is inverted. The memory data is inverted when the supply voltage VC' is 6 V after high heating testing. Then, it may be given as a conclusion of high heating test that the electrons have slipped out of the floating gate, revealing defective insulation of the floating gate. Subsequently, as regards the EPROM of FIG. 1, the minimum value of the supply voltage VC to invert the output data is sought for. If the threshold voltage VTH of the memory cell is 5.5 V, VC is obtained by reversing the sign of inequality of Expression (2) as follows: EQU 5.5<0.4 VC+1.5 EQU VC.degree.10.0
Namely, the data is inverted when the supply voltage is higher than 10 V. The higher the threshold voltage VTH of the memory cell in which the data is written necessitates the higher the supply voltage. However, it is not advisable to apply such a high voltage to the memory because transistors in a circuit with 5 V power supply may possibly be broken. Thus, the EPROM of this type cannot be checked before shipment, leaving room for improvement in reliability.
Operations of a MOS FET may be classified by biasing conditions into two modes; saturated operation (pentode operation) and unsaturated operation (triode operation). These two modes of operation may be expressed, respectively, as follows: EQU VG-VTH-VS.ltoreq.VD-VS (3) EQU VG-VTH-VS>VD-VS (4)
VG is the control gate voltage; VD, drain voltage;
VS, source voltage; and VTH, threshold voltage.
It is known that the pentode operation of the MOS FET would produce a pinch-off region. In the EPROM of FIG. 1, the gate voltage of the MOS FET 5 in the reference signal generator 6 is lower than VC, so that the operation of the MOS FET 5 resembles the pentode operation more than the operation of the memory cell does. Accordingly, electrons may possibly be accumulated gradually in the floating gate of the floating gate MOS FET 5 during prolonged use. As a result, the reference voltage of the differential sense amplifier 4 may be varied to change the speed of data reading from the memory array 2 or to cause wrong data decision. Thus, the reliability of the memory is lowered.
In other conventional ROMs than the EPROM, moreover, the data readout time depends on the charge and discharge time of the output line. As the memory capacity increases, therefore, the stray capacity of the output line increases to prolong the readout time. | {
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Pursuant to 35 U.S.C. xc2xa7119(d) the present application claims priority to China patent application Serial No. 02225418.8, filed Jan. 28, 2002, which is incorporated by reference herein.
A. Field of the Invention
The present invention relates to a roaster for roasting meat or a roaster with a spraying device for roasting meat; more particularly, to an electric roaster for smoked meat.
B. Description of the Prior Art
In general, the process for producing smoked meat includes two steps, that is, roasting and smoking. In the roasters of the prior art, only the process for roasting meat is provided. However, no smoking function is provided in the prior art roasters.
To overcome the above problem of the prior art, the present invention provides an electric roaster for smoked meat which not only has the function of roasting meat, but also provides the function of smoking meat during the roasting.
According to the present invention, there is provided an electric roaster for smoked meat including: an outer shell; an inner pan, covered by heating elements; and an up lid. The electric roaster for smoked meat of the present invention is characterized in that said electric roaster further includes: a tray for containing the meat roasted, a supporting ring, some wood material for producing smoke and an outer pan, wherein said supporting ring is disposed on the bottom of said inner pan; said tray is disposed on said supporting ring; said up lid is disposed on the top of said inner pan; said outer pan is disposed outside said inner pan within said outer shell; and some wood material for producing smoke is put around said supporting ring.
According to a first aspect of the present invention, said inner pan, said tray and said supporting ring are formed to be separate units.
According to a second aspect of the present invention, said supporting ring and the bottom of said inner pan are integrally formed, that is, the bottom of said inner pan has a convex annular platform projected at its center portion with a closed top surface on which said tray is placed.
According to a third aspect of the present invention, the top of said supporting ring and the back of said tray are integrally formed, so that the ring can be taken out along with said tray.
Preferably, said supporting ring is formed to be an oblate a short sleeve with a side wall of mesh structure and an upper and a lower open ends; and said supporting ring is provided between said tray and said inner pan and above the bottom of said inner pan, with its diameter being smaller than those of both said tray and said bottom.
Preferably, said tray is provided with a periphery warped upward. | {
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This invention is concerned with a method of interpolation of any quantity in any point of a sphere as well as with a device to determine an said electrical value and a device to display the topography of a potential field.
It is concerned more particularly with tests of functional exploration in neurology consisting in reading out from the electroencephalogram the brain's electric response as caused by applying a physiological stimulation (acoustical, visual, somesthesical stimulation)to the subject. The response is collected by means of several electrodes distributed over the scalp.
In the existing art, a great number of electrodes are used, that are evenly distributed on the whole spherical surface. The evaluation of the measures between two acquisition points is made by methods of interpolation which do not ensure an adequate accuracy. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to a disposable syringe in the field of medical apparatus, and in particular to a self-destroying disposable syringe and a self-destroying method thereof.
It is a trend that the disposable syringe is used for substituting the reusable syringe, and there have been various types of disposable syringes. A self-destroying syringe disclosed in Chinese patent application no. 200320110786.X and a self-destroying syringe disclosed in Chinese patent application no. 03266160.6 develop in the aspect of avoiding the reuse of syringe. However, there are still some problems, for example, in the former, the self-destroying characteristic is poor due to only a plug fitting with a plug cavity, while in the latter, the configuration is complex for manufacturing. In another Chinese patent application no. 200420105856.7, another self-destroying disposable syringe as shown in FIG. 1 is disclosed, the syringe comprising a needle base 1, a barrel 2, a pushing stem 3, and a piston 4, wherein the end of the needle base 1 is provided with a dual self-destroying ring, the front end of the pushing stem 3 is provided with a hub for fitting with the piston 4, while the rear end is provided with a pawl for interlocking with a self-locking ring of the barrel 2. Though the syringe with the above structure can achieve the function of self-destroying, there are still some problems: 1. the needle base structure is complex and thus increases the resistance to self-destroy, which affects the self-destroy result; 2. the tip end and the spherical protrusion of the pushing stem 3 are hard for manufacturing; 3. the front end of the pushing stem 3 is provided with a pushing disc for fitting with the barrel 2 and sealed by the piston 4, and during the pushing process, negative pressure and resistance may be generated, which goes against the injection; 4. the piston 4 is of abnormal shape and consequently hard for manufacturing. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to ice fishing in general, and specifically to heat type devices for preventing freezing of water in a hole opening through ice.
Prior art heating devices for maintaining open ice fishing holes have not been without significant drawbacks. One type of heating device shown in U.S. Pat. No. 4,612,910 to Williams utilizes a bouyant water proof canister which is floated in the hole, filled with combustible material, and ignited. As the material burns, heat is produced and conducted through the canister. While the water within the ice hole is warmed nicely with this method, the canister is free to bob around in the hole and can easily contact the fishing line which passes through the same hole. Such contact is detrimental and may result in cut or damaged line.
U.S. Pat. No. 4,006,732 to Schumm discloses a gas heater which maintains an open hole and which is anchored to the hole with special legs designed for the purpose. However, the complexity of the Schumm patent is apparent, and the cost of producing such a device can be prohibitive. Schumm also lists several other pertinent patents and the associated drawbacks of each.
Many of the aforementioned disadvantages are overcome by using a device known as a water spitter and disclosed in Panfish, by Sternberg et al, 1983, p. 138. The water spitter disclosed in the prior art is disadvantageous in that little control over the throughput of the device (through thermosiphonic action) is available. Additionally, the prior art water spitter is non-transportable, and requires a significant warm-up period to generate a puddle of water sufficient for operation. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to non-destructive inspection of turbine components. More specifically, the invention provides inspection heads for positioning sensing elements on the surface of turbine rotor discs on either a fully assembled rotor or on discs that have been removed from the rotor in a controlled, repeatable manner.
2. Description of the Related Art
The blades of steam turbines are attached to discs and are subjected to significant stress due to the heat, pressure, and vibrations within their operating environments. It is therefore necessary to periodically inspect these discs for surface cracking, internal cracking, and pitting at the blade attachment area and the rotor attachment area, known as the disc bore. If such inspections locate indications of defects beginning to form that are not sufficient to take the disc out of service, it is desirable to ensure that later inspections focus on locations within the discs where the indications were found in the previous inspection.
Turbine discs are presently inspected using sensing elements such as ultrasonic probes and eddy current probes, the operation of which is well known in the art. Presently used probes are hand held, thereby limiting the positional accuracy of the inspection, and the repeatability with which the probes may be positioned.
Accordingly, there is a need for a means of accurately and repeatably positioning an inspection probe in a desired location with respect to a turbine disc. There is an additional need for such probes to fit within the small space available between discs within a typical turbine rotor assembly, thereby avoiding a need to remove the discs from the turbine for inspection. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to a RAM (Random Access Memory) using a MOS FET (Metal Oxide Semiconductor Field Effect Transistor) and more particularly to a dynamic RAM consisting of one transistor/one capacitor memory cells.
2. Description of the Prior Art
Generally, when a random access memory (RAM) is formed on a semiconductor substrate, the areas occupied by the individual memory cells take up almost the whole area of the memory chip. In the latest MOS type semiconductor memory devices, in order to increase the memory capacity, what is known as the one transistor/one capacitor cell system has become the main trend and is being widely used. In this system, the area occupied by a single memory cell is small and the structure which consists of one transistor and one capacitor for each bit is simple.
As is well known this one transistor/one capacitor cell consists of a MOS transistor for reading out and writing in information and a capacitor connected in series between the MOS transistor and a power source for storing the information. Furthermore an address line is connected to a gate electrode of the MOS transistor and a digit line is connected to an electrode region of the MOS transistor. In this memory cell the reading out and writing in of information takes place by charging and discharging the capacitor controlling the MOS transistor. Conventionally this memory cell is formed as a semiconductor integrated circuit as follows. A polycrystalline silicon gate electrode of the MOS transistor is formed bridging two diffused electrode regions, one of which is connected to the impurity diffused data line. An electrode of the capacitor made of polycrystalline silicon is formed adjacent to the MOS transistor on a semiconductor substrate with an insulating layer between this layer and the substrate. When the highest voltage is applied to the electrode of the capacitor, an inversion layer in the semiconductor substrate is formed, which works as both another electrode region of the MOS transistor and another electrode of the capacitor. Thereby a one transistor/one capacitor memory cell is formed. An address line made of aluminum disposed above an insulating layer is connected to the gate electrode at the contact portion.
The above-mentioned memory cell has some drawbacks. First, the MOS transistor is connected to the metal layer, which constitutes the address line, by the gate electrode, and one contact hole is needed per memory cell for electrical connection between this metal layer and the polycrystalline layer which constitutes this gate electrode. Therefore, as the memory capacity is increased, the number of contact holes on the semiconductor substrate also increases, which makes the chip size large. On the other hand, in order to make the integration density higher it is necessary to make the size of the contact holes more and more minute, and in this respect lowering of the manufacturing yield cannot be avoided. Also, a second drawback is that in the manufacture of the memory cell the gate electrode of the above-mentioned MOS transistor and one electrode of the capacitor are made in the same step. Specifically, a polycrystalline silicon layer is formed over the whole surface and then is etched away leaving two polycrystalline silicon electrodes. Accordingly, in order to make sure of separating the gate electrode of the MOS transistor and one electrode of the capacitor, the gap between the polycrystalline silicon layers must be at least about 5.mu.. This is the limiting value in the present state of separation etching by using a mask pattern, and the wasteful presence of such a space between the transistor and the capacitor, in addition to the first drawback, is still more undesirable as regards increasing the degree of integration. | {
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An amplifier is a device designed to increase the power of an input signal by controlling the output of the amplifier to match the shape of the input signal. Typically, an amplifier modulates the output of a power supply based on the input signal, thereby outputting a signal that has the same waveform of the input signal but at a higher amplitude. A radio frequency (RF) power amplifier is a type of amplifier that converts a low-power RF signal into a higher power RF signal, typically used to drive an antenna to transmit the higher power RF signal. | {
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The present invention relates to the field of powering a system comprising multiple components, and in particular to a system and entities for DC power pooling.
Systems comprising multiple modules, such as communication systems, commonly comprise modules having on-board power supplies that are connected to a common mains. In order to provide uninterrupted operation of the system, including during failure of power mains, systems often comprise a back-up power supply, such as an uninterruptible power supply (UPS), which during a power interrupt functions to supply AC power to each of modules in the system.
The combination of modules each comprising an on-board power supply often leads to a less than optimum situation, in which the on-board power supply of some modules are operating at low utilization, while the on-board power supply of other modules are approaching or have reached maximum utilization. Power supply longevity is at least partially a function of the utilization rate, in which typically a highly utilized power supply begins to increase in temperature. This increase in temperature leads to a shortened life for the power supply.
Certain modules, for example an Ethernet switch having power over Ethernet functionality, may have a need for additional power above that available from the on-board power supply. Prior art systems require a dedicated additional power supply to be added as a module, feeding the additional required power. Such a dedicated additional power supply is required despite the on-board power supply of other modules in the system being at low utilization, thus having spare power available. Furthermore, in prior art systems, a dedicated additional power supply will typically be initially underutilized, and will only experience optimum utilization as the system power needs grow. This underutilized dedicated additional power supply is thus unavailable in the event that one of the other modules in the system has reached maximum utilization of its on-board power supply.
In the event that one of the modules in the system experiences an on-board power supply failure, the prior art further does not teach an arrangement for supplying power to the module in place of the local power supply. Furthermore, the prior art does not teach an arrangement in which the utilization of local power supplies is optimized.
U.S. Pat. No. 6,125,448 issued to Schwan et al. discloses a method and apparatus of powering components on a network by using a load-share technique and by using over-voltage and current limiting circuitry. Under normal operation of the power subsystem, the load will be powered directly from the power subsystem. Unfortunately, no means of optimization of overall network power is described.
U.S. Pat. No. 5,745,670 issued to Linde discloses a fault tolerant power supply system including a plurality of nodes coupled to a common power distribution bus. Under normal operation of the power subsystem, the load will be powered directly from the power subsystem, and excess power is available to be supplied to the bus. Upon failure of the local power supply, bus power is supplied under certain conditions. No means of optimization of overall network power is described, and no means of centralized control of individual local power supplies exist.
IEEE 1394 specification, “IEEE Standard for a High Performance Serial Bus”, IEEE Std 1394-1995, Aug. 30, 1996, describes a high speed serial bus that includes the capability for sourcing power from one “node” to another over a power bus coupling the nodes. This power sourcing capability introduces potential complexities into the process of configuring the power source/sink relationships between a set of nodes or systems, such as those coupled by a 1394 specification compliant bus. For example, at any given time, one node should be providing or sourcing power and the remaining nodes should either consume power as a power sink, power themselves, or act as a power “conduit” distributing power from the power source to nodes coupled to the power distribution bus or cable (but not directly coupled to the power source). Such a layout does not teach an arrangement or a means allowing for optimization of overall network power.
U.S. Pat. No. 6,539,484 issued to Cruz describes an electronically configurable physical arrangement of power transistors. The arrangement is configurable under externally derived electrical signals to: sink power to a node from a power bus segment; source power from the node to a power bus segment; and distribute power through the node. Such an arrangement allows flexibility and power sharing, however it does not optimize overall network power.
There is therefore a need for an arrangement in which the utilization of local power supplies is optimized. | {
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Some connection systems between electronic components such as printed circuit boards (PCBs), backplanes, cables, integrated circuits (ICs), IC connectors and the like, use metal pins and metallic, plated-through cylinders called vias. Often, such a system includes one electronic component which has a set of metal pins and another component which has a corresponding set of vias. In general, the component with the pins includes a housing which positions the pins such that the pins extend from the housing in a grid-like manner (e.g., in rows and columns). Similarly, the component with the vias typically arranges the vias in a complementary manner such that holes of the vias align with ends of the pins when the two components are brought into alignment with one another.
In general, to connect the two components, the housing of the pin-providing component is positioned relative to the via-providing component such that the end of each pin properly aligns with a corresponding via hole. Then, the housing of the pin-providing component and the via-providing component are brought together so that the metal pins evenly insert into the via holes. There are different conventional approaches to making sure that the connections between the pins and the vias are secure.
One conventional approach is called xe2x80x9creflow solderingxe2x80x9d or the xe2x80x9cwave solderingxe2x80x9d. In this approach, wave soldering machinery typically solders the pins and vias together once the pins have been inserted into the vias. In general, molten solder flows through the remaining voids between the pins and the vias to form electrical pathways for carrying signals between the pins and the vias.
Typically, the reflow approach uses a grid pattern pitch of approximately 0.100 of an inch or 0.100xe2x80x3 (often pronounced xe2x80x9c100 milsxe2x80x9d). That is, the pins are arranged generally in rows and columns such that the center axis of each pin is approximately 0.100xe2x80x3 away from the center axes of pins in adjacent rows and columns. Similarly, the vias typically are arranged in complementary rows and columns such that the center axis of each via is approximately 0.100xe2x80x3 away from the center axes of vias in adjacent rows and columns.
For the reflow soldering approach, the diameters of the holes of the vias typically are 100% larger than the maximum cross-sectional dimension of the pins in order to promote solder flow within the vias once the pins have been inserted. For example, for a round pin having a maximum diameter of 0.030xe2x80x3, the inner diameter of the via hole is generally 0.060xe2x80x3.
In general, pins having a square cross-section, which are stamped from flat metal stock, are also suitable for use in the reflow soldering approach. Such square cross-sectioned shaped pins generally are less expensive than pins having a circular cross-section or pins with rounded corners since the square cross-sectioned pins typically do not need to undergo a tumbling, coining or turning process to round the comers of the pins. Rather, the pin manufacture can simply cut/punch/stamp the square cross-sectioned pins from a sheet of metal stock. Accordingly, the thickness of each pin is essentially the width of the metal stock. Although flat pins are less expensive than rounded pins, better soldering results typically are obtained with pins having circular cross-sections or rounded corners than with pins having a square or rectangular cross-section and sharp comers.
Another approach to forming secure connections is the xe2x80x9cintrusive reflow solderingxe2x80x9d approach. In this approach, automated equipment typically provides portions of solder and flux for each pin/via combination prior to insertion of the pins into the via holes. Often, the equipment partially inserts these solder portions (sometimes in the form of a paste and sometimes as solder pre-forms assembled to the pin base) into the via holes of a component prior to pin insertion. Then, the equipment brings the pin-providing component and the via-providing component together by inserting the pins of the pin-providing component into the via holes of the via-providing component. The equipment then provides heat to melt the solder portions and additional solder to fill any remaining voids between the pins and the vias.
Typically, the grid pattern for the intrusive reflow approach has a pitch that is similar to that used in the reflow soldering approach (i.e., 0.100xe2x80x3), or a finer pitch in the range of 0.080xe2x80x3 to 0.100xe2x80x3. Furthermore, for the intrusive reflow soldering approach, the diameters of the vias holes typically are not 100% larger than the maximum cross-sectional dimension of the pins, as in the reflow soldering approach. Rather, the via holes for the intrusive reflow approach generally can be 25% larger than the maximum cross-sectional dimension of the pins for sufficient solder distribution since pre-placement of the solder portions facilitates solder delivery into the via holes.
For the intrusive reflow soldering approach, as in the reflow soldering approach, square or round cross-sectioned pins are generally preferred. Pins having a round cross-section are ideally suited for intrusive reflow soldering. Pins having a square cross-section are generally suitable but require more solder. Pins having a rectangular (but non-square) cross-section typically are not used in the reflow soldering approach since such pins provide little or no additional benefit over pins having a square cross-section.
Another approach to forming secure connections between two components is called the xe2x80x9ccompression fitxe2x80x9d approach. This approach is also known as the xe2x80x9ccompliant fitxe2x80x9dor the xe2x80x9ceye-of-the-needlexe2x80x9d approach. In this approach, no solder is used. Rather, each pin typically is flat (i.e., each pin has a square or rectangular cross-section) and has a hole (or eye) stamped through it (i.e., the xe2x80x9ceye-of-the-needlexe2x80x9d) allowing the pin to compress when inserted into a via to form a secure connection. In particular, each pin has a cross-sectional diameter that is sized to be larger than the cross-section diameter of its corresponding via hole to provide an interference fit when inserted into that via hole. Accordingly, when the pins are inserted into the holes of the vias, the pins compress to fit within the via holes and apply pressure against the inner metallic surfaces of the vias (e.g., copper-plated surfaces). As a result, the connections formed between the pins and vias are secure.
Typically, the compression fit approach uses a finer grid pattern pitch than either the reflow soldering approach or the intrusive reflow soldering approach. One example of a pitch that is suitable for the compression fit approach is an 0.080xe2x80x3 by 0.060xe2x80x3 grid. Connection systems which used grids of this size are often called xe2x80x9chigh-densityxe2x80x9d due to the large number of connections (i.e., pin/via connections) that can be formed in such a small area.
Typically, pins which have a rectangular or even square cross-section are used in the compression fit approach. The range for a typical width for a rectangular pin suitable for use in the compression fit approach is 0.012xe2x80x3 to 0.015xe2x80x3. The range for a typical pin length is 0.026xe2x80x3 to 0.028xe2x80x3. The sides of the compression-fit pin typically are allowed to vary by 0.002xe2x80x3 in either direction. A particular characteristic of compression fit pins is their central portions which have a bulging shape. That is, the shape of the eye and the pin material around the eye is designed to provide a particular form factor, and a particular size reduction when inserted into a via.
Unfortunately, there are disadvantages to the conventional reflow soldering, compression fit and intrusive reflow soldering approaches. For example, the conventional reflow soldering approach generally is not used in high-density connection applications (e.g., in connection arrangements having rows and columns less than 0.100xe2x80x3 apart) for several reasons. In particular, reflow soldering connection systems are susceptible to tail shorts, i.e., shorts formed by excess solder hanging from pin ends extending from adjacent via holes. Additionally, the via holes are typically sized to be 100% larger than the maximum pin diameters to promote solder flow within the via holes. This size restriction imposes a limit on how small the grid pattern pitch of the connection system can be before significantly increasing the likelihood of forming unwanted shorts between adjacent vias. Moreover, any reduction in the size of the via would tend to hinder solder flow around the standard reflow soldering pins thus creating excessive voids within the via holes which would pose manufacturing yield difficulties and product reliability issues. Furthermore, in a high-density configuration, solder, which occasionally flows or xe2x80x9cwicks upxe2x80x9d the lengths of the pins and flows out the ends of the via holes closest to the housing (e.g., a connector body) holding the pins, would be more likely to cause shorts directly beneath the housing. Such shorts may be hidden by the housing and inaccessible for detection and/or repair.
The compression fit approach suffers from manufacturing yield and reliability drawbacks as well. In particular, formation of high-density connections between compression fit pins and vias typically require high insertion forces (particularly compared to low or zero insertion force situations for reflow soldering pins and vias). Accordingly, a small abnormality (e.g., a bend or irregular shape which places a pin or via slightly out of tolerance) can cause the pin to collapse or bend improperly, or cause the via to distort. As a result, the electrical connection, if made at all, will likely be unreliable.
The intrusive reflow soldering approach also suffers from certain drawbacks. In particular, this approach is complex and expensive to implement. In particular, specialized procedures, equipment and soldering materials are required to pre-position solder at the via holes prior to pin insertion, insert the pins and then apply heat and additional solder to form secure connections between components. Some component manufacturers have been known to prefer the reflow soldering approach or the compression fit approach over the intrusive reflow soldering approach due to the added complexity and expense which typically characterizes the intrusive reflow soldering approach.
In contrast to the above-described conventional approaches, the invention is directed to techniques for forming a soldered connection using a pin having a channel. The channel enables the pin to form a secure connection with a via (e.g., by facilitating gas percolation out of the via hole during soldering to improve solder flow, by holding solder prior to pin insertion and soldering, or by facilitating accurate pin bending to hold solder or a pin insert member prior to pin insertion and soldering) to improve connection system reliability and increase manufacturing yields.
In one arrangement, the pin has a surface which includes (i) a first surface area, (ii) a second surface area that is substantially parallel to the first surface area, and (iii) a channel surface area which defines a channel that extends from the first surface area toward the second surface area. To form a soldered connection, the pin is inserted into a cavity defined by a via of a connecting member (e.g., a circuit board), in a direction that is parallel to a central axis of the via. The pin is then soldered to the via to establish an electrical pathway between the pin and the via. Depending on the particular arrangement (as will be explained in further detail below), the channel generally facilitates the introduction of solder into the cavity of the via. Accordingly, the cavity dimension of the via can be smaller than that required for vias of the conventional reflow soldering approach (i.e., less than 100% of the maximum pin cross-section as is typically required for the conventional reflow soldering approach). Hence, the invention is suitable for use in high-density, micro-soldered connection arrangements (e.g., in situations with vias closer together than in the conventional reflow soldering approach).
In one arrangement, the channel is a tunnel that extends from a first plane defined by the first surface area to a second plane defined by the second surface area through the pin. In this arrangement, the channel allows gas within the via hole to escape out of the remaining voids within the via cavity during soldering. Preferably, the pin is located relative to the via such that a portion of the channel extends outside the cavity defined by the via to facilitate gas percolation even when solder has almost filled the via cavity. Additionally, the channel provides additional surface area for drawing solder. In a preferred arrangement, a solder-stop member is placed around the pin such that a first portion of the channel extends on a first side of the solder-stop member and a second portion of the channel extend on a second side of the solder-stop member that is opposite the first side. Such an arrangement helps block solder such that it is less likely to escape out of the via cavity while continuing to enable gas to escape through the channel.
In this arrangement, the presence of the channel promotes solder flow within the via cavity to the extent that the via cavity can be made narrow (e.g., less than 100% of the maximum pin diameter as is typically used in a conventional reflow soldering approach). Accordingly, the via can be positioned closer to other neighboring vias in a high-density connection arrangement. Hence, the benefits of forming a soldered connection (e.g., high reliability and improved manufacturing yields) can be derived in a high-density, micro-soldered configuration.
In the above-described arrangement, the channel preferably extends along a central axis of the pin to facilitate gas percolation and to promote solder flow. In one arrangement, the channel extends all the way to the end of the pin to form a solder flow path. That is, the channel includes a gap at the end of the pin. Such a gap facilitates entry of the solder into the via cavity (and particularly the channel) during soldering.
In one arrangement, a portion of solder can be positioned within the channel prior to soldering. Accordingly, less solder is required to flow into the via hole during soldering. Preferably, the solder is fitted within the channel (e.g., by automated equipment) such that (i) a first portion of the piece of solder extends from the channel of the pin in a first direction, and (ii) a second portion of the piece of the solder extends from the channel of the pin in a second direction that is opposite the first direction. Preferably, the first and second portions are substantially the same amounts. Any amounts that interfere with pin insertion can be shaped prior to insertion to provide a minimal or zero insertion force fit.
In another arrangement, the first surface area defines a first plane, the second surface area defines a second plane that is parallel to the first plane, and the channel extends from the first plane toward the second plane to enable machinery (e.g., automated equipment) to bend the pin along the channel prior to insertion of the pin into the via hole. In this arrangement, the channel preferably forms a groove along one of the sides of the pin to facilitate accurate and controlled bending of the pin along the channel since no material needs to be displaced in the channel region during bending.
In one arrangement, the pin further includes multiple tab portions which bend around a pin insert member when the pin is bent. The multiple tab portions of the pin hold the pin insert member in place during soldering. The pin insert member is preferably metallic and contributes both structural strength and electrical conductivity to the connection formed between the pin and the via.
In another arrangement, the channel is a groove or slot which divides the pin into a first pin portion and a second pin portion. In this arrangement, the first and second pin portions are bent relative to each other such that the first and second pin portions hold a piece of solder for soldering. Accordingly, the piece of solder enters the via hole prior to soldering and less solder is required to flow into the via hole during soldering. Preferably, the surface of the pin further includes a first side-channel surface area that defines a first side-channel (in addition to the grooved-channel), and a second side-channel surface area that defines a second side-channel. In this arrangement, the first and second side-channels are essentially holes which extend along a direction that is parallel to the central axis of the via. Accordingly, gas can percolate out of the via hole through these multiple side-channels during soldering.
Preferably, the pin has a cross-section that is less than or equal to a cross-section of the cavity defined by the via. Accordingly, insertion of pin into the via hole requires little or no insertion force (e.g., xe2x80x9ca zero insertion force connection systemxe2x80x9d). This arrangement reduces the likelihood of bending the pin or distorting the via during pin insertion.
In the above-described arrangements of the invention, it should be understood that there is no restriction on the shape of the pin or its channel (as there is in the compression fit approach where a compression fit pin is designed to provide a particular cross-sectional reduction during insertion into a via). Accordingly, the top portion of the pin (or neck), which is adjacent the housing holding the pin, can be made thicker than compression fit pins to further prevent pin bending during pin insertion.
The features of the invention, as described above, may be employed in electronic systems and related components such as those manufactured by EMC Corporation of Hopkinton, Mass. | {
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This invention relates to mobile phones or media players and other portable/mobile electronics and devices aimed at providing a useful cover for smart phones or media players for their protection aimed at all the users of smart phones and media players. More specifically, the disclosed invention relates to a cover designed for smart phones, media players and other portable/ mobile electronics and devices which does not use a clip as an attachment on the cover, as is used by other covers, but has an inbuilt clip which is very thin welded on to the back of the cover. The cover itself is very thin and hence the cover with the clip is very light weight and does not spoil the aesthetics of the cover unlike other covers designed for mobile phones or media players.
With the invention of mobile phones and their proliferation during the past decade, mobile phones have become the necessity of the people and therefore its demand has led to extensive research in this field, and the technological advancements have led to newer applications being invented which can be used in a single mobile phone and has also led to the shrinking of the size of the phone. Therefore, now the mobile phones have a variety of applications, through the internet, people are connected throughout the world and the internet has become a necessity today where people not only connect with each other, but also exchange ideas and valuable information on the internet. This has led to the invention of smart phones which has helped people remain connected while on the move. The smart phones are mini computers which help people access data and process information.
The current invention provides for protection of such smart phones and media players as their users carry them all the time while at home, in the office or on the move. The protection provided is in the form of a poly carbonated cover, making the back of the cover/cover the clip that is used to secure the smart phone and/or media player to a waistband or belt or other surface that is chosen by the user, a very thin clip is joined to the cover by ultrasonic welding to the cover.
No invention to the knowledge of the inventor has disclosed an apparatus which has features as that of the present invention. No other invention has provided for an apparatus with portability, extra protection, lightweight, and which tightly clamps on and the phone cannot fall or slip off easily.
The limitations and non-effectiveness of the prior art has been overcome by the instant invention as described below. 1) In a previously published patent, Patent Publication No. —U.S. Pat. No. 8,177,107 B2, Publication Date—15 Mar., 2012, a patent for mobile covers was patented, but the clip is not welded to the back of the cover with the ultrasonic welding as is done in the present invention which provides strength and durability and does not spoil the aesthetics of the cell phone. This application only attaches a new component and does not use the back cover itself. 2) In a previously published patent, Publication no. —U.S. Pat. No. 7,110,802 B1, Publication Date—Sep. 19, 2006, a patent for mobile covers was patented, but the clip is again not welded to the back of the cover with the ultrasonic welding as is done in the present invention which provides strength and durability and does not spoil the aesthetics of the cell phone. This application also does not use the functions of the current invention, this is in fact a holster. 3) In a previously published patent, Publication no.—WO2007142382 A1, Publication Date—Dec. 13, 2007, a patent for mobile covers was patented, but the clip is again not welded to the back of the cover with the ultrasonic welding as is done in the present invention which provides strength and durability and does not spoil the aesthetics of the cell phone. This application focuses on rotation of the mobile phone at different angles when the cover is put on the cell phone. | {
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1. Field of the Invention:
The present invention relates to an apparatus and a method for processing a multi-channel audio signal and, in particular, to an apparatus and a method for processing a multi-channel audio signal in a stereo-compatible manner.
In recent times, the multi-channel audio reproduction technique is becoming more and more important. This may be due to the fact that audio compression/encoding techniques such as the well-known mp3 technique have made it possible to distribute audio records via the Internet or other transmission channels having a limited bandwidth. The mp3 coding technique has become so famous because of the fact that it allows distribution of all the records in a stereo format, i.e., a digital representation of the audio record including a first or left stereo channel and a second or right stereo channel.
Nevertheless, there are basic shortcomings of conventional two-channel sound systems. Therefore, the surround technique has been developed. A recommended multi-channel-surround representation includes, in addition to the two stereo channels L and R, an additional center channel C and two surround channels Ls, Rs. This reference sound format is also referred to as three/two-stereo, which means three front channels and two surround channels. Generally, five transmission channels are required. In a playback environment, at least five speakers at the respective five different places are needed to get an optimum sweet spot in a certain distance from the five well-placed loudspeakers.
Several techniques are known in the art for reducing the amount of data required for transmission of a multi-channel audio signal. Such techniques are called joint stereo techniques. To this end, reference is made to FIG. 10, which shows a joint stereo device 60. This device can be a device implementing e.g. intensity stereo (IS) or binaural cue coding (BCC). Such a device generally receives —as an input—at least two channels (CH1, CH2, . . . CHn), and outputs a single carrier channel and parametric data. The parametric data are defined such that, in a decoder, an approximation of an original channel (CH1, CH2, . . . CHn) can be calculated.
Normally, the carrier channel will include subband samples, spectral coefficients, time domain samples etc, which provide a comparatively fine representation of the underlying signal, while the parametric data do not include such samples of spectral coefficients but include control parameters for controlling a certain reconstruction algorithm such as weighting by multiplication, time shifting, frequency shifting . . . The parametric data, therefore, include only a comparatively coarse representation of the signal or the associated channel. Stated in numbers, the amount of data required by a carrier channel will be in the range of 60-70 kbit/s, while the amount of data required by parametric side information for one channel will be in the range of 1.5-2.5 kbit/s. An example for parametric data are the well-known scale factors, intensity stereo information or binaural cue parameters as will be described below.
Intensity stereo coding is described in AES preprint 3799, “Intensity Stereo Coding”, J. Herre, K. H. Brandenburg, D. Lederer, February 1994, Amsterdam. Generally, the concept of intensity stereo is based on a main axis transform to be applied to the data of both stereophonic audio channels. If most of the data points are concentrated around the first principle axis, a coding gain can be achieved by rotating both signals by a certain angle prior to coding. This is, however, not always true for real stereophonic production techniques. Therefore, this technique is modified by excluding the second orthogonal component from transmission in the bit stream. Thus, the reconstructed signals for the left and right channels consist of differently weighted or scaled versions of the same transmitted signal. Nevertheless, the reconstructed signals differ in their amplitude but are identical regarding their phase information. The energy-time envelopes of both original audio channels, however, are preserved by means of the selective scaling operation, which typically operates in a frequency selective manner. This conforms to the human perception of sound at high frequencies, where the dominant spatial cues are determined by the energy envelopes.
Additionally, in practically implementations, the transmitted signal, i.e. the carrier channel is generated from the sum signal of the left channel and the right channel instead of rotating both components. Furthermore, this processing, i.e., generating intensity stereo parameters for performing the scaling operation, is performed frequency selective, i.e., independently for each scale factor band, i.e., encoder frequency partition. Preferably, both channels are combined to form a combined or “carrier” channel, and, in addition to the combined channel, the intensity stereo information is determined which depend on the energy of the first channel, the energy of the second channel or the energy of the combined or channel.
The BCC technique is described in AES convention paper 5574, “Binaural cue coding applied to stereo and multi-channel audio compression”, C. Faller, F. Baumgarte, May 2002, Munich. In BCC encoding, a number of audio input channels are converted to a spectral representation using a DFT based transform with overlapping windows. The resulting uniform spectrum is divided into non-overlapping partitions each having an index. Each partition has a bandwidth proportional to the equivalent rectangular bandwidth (ERB). The inter-channel level differences (ICLD) and the inter-channel time differences (ICTD) are estimated for each partition for each frame k. The ICLD and ICTD are quantized and coded resulting in a BCC bit stream. The inter-channel level differences and inter-channel time differences are given for each channel relative to a reference channel. Then, the parameters are calculated in accordance with prescribed formulae, which depend on the certain partitions of the signal to be processed.
At a decoder-side, the decoder receives a mono signal and the BCC bit stream. The mono signal is transformed into the frequency domain and input into a spatial synthesis block, which also receives decoded ICLD and ICTD values. In the spatial synthesis block, the BCC parameters (ICLD and ICTD) values are used to perform a weighting operation of the mono signal in order to synthesize the multi-channel signals, which, after a frequency/time conversion, represent a reconstruction of the original multi-channel audio signal.
In case of BCC, the joint stereo module 60 is operative to output the channel side information such that the parametric channel data are quantized and encoded ICLD or ICTD parameters, wherein one of the original channels is used as the reference channel for coding the channel side information.
Normally, the carrier channel is formed of the sum of the participating original channels.
Naturally, the above techniques only provide a mono representation for a decoder, which can only process the carrier channel, but is not able to process the parametric data for generating one or more approximations of more than one input channel.
To transmit the five channels in a compatible way, i.e., in a bitstream format, which is also understandable for a normal stereo decoder, the so-called matrixing technique has been used as described in “MUSICAM surround: a universal multi-channel coding system compatible with ISO 11172-3”, G. Theile and G. Stoll, AES preprint 3403, October 1992, San Francisco. The five input channels L, R, C, Ls, and Rs are fed into a matrixing device performing a matrixing operation to calculate the basic or compatible stereo channels Lo, Ro, from the five input channels. In particular, these basic stereo channels Lo/Ro are calculated as set out below:Lo=L+xC+yLs Ro=R+xC+yRs
x and y are constants. The other three channels C, Ls, Rs are transmitted as they are in an extension layer, in addition to a basic stereo layer, which includes an encoded version of the basic stereo signals Lo/Ro. With respect to the bitstream, this Lo/Ro basic stereo layer includes a header, information such as scale factors and subband samples. The multi-channel extension layer, i.e., the central channel and the two surround channels are included in the multi-channel extension field, which is also called ancillary data field.
At a decoder-side, an inverse matrixing operation is performed in order to form reconstructions of the left and right channels in the five-channel representation using the basic stereo channels Lo, Ro and the three additional channels. Additionally, the three additional channels are decoded from the ancillary information in order to obtain a decoded five-channel or surround representation of the original multi-channel audio signal.
Another approach for multi-channel encoding is described in the publication “Improved MPEG-2 audio multi-channel encoding”, B. Grill, J. Herre, K. H. Brandenburg, E. Eberlein, J. Koller, J. Mueller, AES preprint 3865, February 1994, Amsterdam, in which, in order to obtain backward compatibility, backward compatible modes are considered. To this end, a compatibility matrix is used to obtain two so-called downmix channels Lc, Rc from the original five input channels. Furthermore, it is possible to dynamically select the three auxiliary channels transmitted as ancillary data.
In order to exploit stereo irrelevancy, a joint stereo technique is applied to groups of channels, e. g. the three front channels, i.e., for the left channel, the right channel and the center channel. To this end, these three channels are combined to obtain a combined channel. This combined channel is quantized and packed into the bitstream. Then, this combined channel together with the corresponding joint stereo information is input into a joint stereo decoding module to obtain joint stereo decoded channels, i.e., a joint stereo decoded left channel, a joint stereo decoded right channel and a joint stereo decoded center channel. These joint stereo decoded channels are, together with the left surround channel and the right surround channel input into a compatibility matrix block to form the first and the second downmix channels Lc, Rc. Then, quantized versions of both downmix channels and a quantized version of the combined channel are packed into the bitstream together with joint stereo coding parameters.
Using intensity stereo coding, therefore, a group of independent original channel signals is transmitted within a single portion of “carrier” data. The decoder then reconstructs the involved signals as identical data, which are rescaled according to their original energy-time envelopes. Consequently, a linear combination of the transmitted channels will lead to results, which are quite different from the original downmix. This applies to any kind of joint stereo coding based on the intensity stereo concept. For a coding system providing compatible downmix channels, there is a direct consequence: The reconstruction by dematrixing, as described in the previous publication, suffers from artifacts caused by the imperfect reconstruction. Using a so-called joint stereo predistortion scheme, in which a joint stereo coding of the left, the right and the center channels is performed before matrixing in the encoder, alleviates this problem. In this way, the dematrixing scheme for reconstruction introduces fewer artifacts, since, on the encoder-side, the joint stereo decoded signals have been used for generating the downmix channels. Thus, the imperfect reconstruction process is shifted into the compatible downmix channels Lc and Rc, where it is much more likely to be masked by the audio signal itself.
Although such a system has resulted in fewer artifacts because of dematrixing on the decoder-side, it nevertheless has some drawbacks. A drawback is that the stereo-compatible downmix channels Lc and Rc are derived not from the original channels but from intensity stereo coded/decoded versions of the original channels. Therefore, data losses because of the intensity stereo coding system are included in the compatible downmix channels. A stereo-only decoder, which only decodes the compatible channels rather than the enhancement intensity stereo encoded channels, therefore, provides an output signal, which is affected by intensity stereo induced data losses.
Additionally, a full additional channel has to be transmitted besides the two downmix channels. This channel is the combined channel, which is formed by means of joint stereo coding of the left channel, the right channel and the center channel. Additionally, the intensity stereo information to reconstruct the original channels L, R, C from the combined channel also has to be transmitted to the decoder. At the decoder, an inverse matrixing, i.e., a dematrixing operation is performed to derive the surround channels from the two downmix channels. Additionally, the original left, right and center channels are approximated by joint stereo decoding using the transmitted combined channel and the transmitted joint stereo parameters. It is to be noted that the original left, right and center channels are derived by joint stereo decoding of the combined channel. | {
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Initial industrial design concepts and customer requirements typically limited the assembly and disassembly of a set-top box (STB) and hard disk drive (HDD) dock enclosures so as to prevent non-skilled technicians, using traditional tools, from assembling and disassembling the coupled devices. Typically, the coupling of STBs to HDD dock enclosures is designed to limit access to the internal features of the enclosure. For example, typical designs would not permit the opening of the STB to install the HDD or access an internal cable assembly. Therefore, it is desirable to improve systems and apparatuses to provide a robust and customizable interface for the transfer of data.
Like reference numbers and designations in the various drawings indicate like elements. | {
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As mobile terminal devices, for example, a tablet computer, become increasingly popular with users, the users pay more and more attention to the characters of thinness and thickness of a complete appliance of a mobile terminal device.
For the thickness of the complete appliance of the mobile terminal device in the prior art, the volume and the thickness of a loudspeaker box may greatly affect the thickness design of the complete appliance of the mobile terminal device. However, in the prior art, a loudspeaker is generally placed in a sealed box to form a sealed loudspeaker box, and as shown in FIG. 1, the loudspeaker 1 is placed in the box 2, where the box 2 includes a front housing and a rear housing, a foam 3 is placed between the loudspeaker 1 and an inner surface of the front housing of the box 2, and a gap is reserved between the loudspeaker 1 and the rear housing of the box 2 to finally form a sealed loudspeaker box.
However, the inventor found that, in the prior art, the thickness of the loudspeaker box in the prior art is formed of the wall thickness of the front housing and the wall thickness of the rear housing of the box, the thickness of the foam and the thickness of the loudspeaker; and because the thickness of the loudspeaker box may be affected by the four thicknesses and the placing position of the front housing, the rear housing of the box, the foam and the loudspeaker, in which the four thicknesses refer to the wall thickness of the front housing and the wall thickness of the rear housing of the box, the thickness of the foam and the thickness of the loudspeaker, the loudspeaker box may be very thick, and the complete appliance of the mobile terminal device may be very thick if the loudspeaker box is placed in the mobile terminal device. | {
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This invention relates to hydrolyzable derivatives of poly(ethylene glycol) useful as prodrugs and as degradable components of cross-linked polymers.
Covalent attachment of the hydrophilic polymer, poly(ethylene glycol), commonly referred as PEG, to biologically active agents and surfaces has important applications in biotechnology and medicine.
PEG is generally soluble in water and many organic solvents. PEG is also substantially non-toxic and normally does not elicit any significant immune response in animals. When PEG is chemically attached to a water insoluble compound, the resulting conjugate generally is soluble in water as well as many organic solvents. When the agent to which PEG is attached is biologically active, such as a drug, the activity of the agent can be retained after the attachment of PEG, and the conjugate generally displays altered pharmacokinetics.
The prodrug approach, in which drugs are released by degradation of more complex agents (prodrugs) under physiological conditions, is a powerful component of drug delivery. See R. B. Greenwald, Exp. Opin. Ther. Patents, 7(6):601-609 (1997).
Prodrugs can, for example, be formed by bonding PEG to drugs using linkages which are degradable under physiological conditions.
However, not all linkages are readily degradable and useful in prodrug applications. In general, ester linkages, formed by condensation reactions between PEG carboxylic acids or activated PEG carboxylic acids and alcohol groups on drugs, hydrolyze under physiological conditions to release the drug. For example, in PCT Publication No. WO 96/23794, it is disclosed that paclitaxel can be linked to PEG using ester linkages and the linked paclitaxel can be released in serum by hydrolysis. Antimalarial activity of dihydroartemisinin bonded to PEG through a hydrolyzable ester linkage has also been demonstrated. Bentley et al., Polymer Preprints, 38(1):584 (1997).
Conventional amide and carbamate linkages, formed with amine groups on drugs, generally are stable and do not hydrolyze to release a free drug within a sufficiently short time that is required in practical applications. See, e.g., Zalipsky, Advanced Drug Delivery Reviews, 16:157-182 (1995); Zalipsky, et al., Eur. Polym. J., 19:1177-1183 (1983). For example, it has been demonstrated that carbamate linkages between PEG and a protein in a conjugate are stable under a variety of physiological conditions. Larwood and Szoka, J. Labeled Compd. Radiopharm. 21:603 (1984). Many useful drugs including peptides, proteins, and small agents having amine groups have been bonded to PEG through non-hydrolyzable amide and carbamate linkages. PEG can also be bonded to amine groups on drugs through reductive amination with PEG aldehydes and the resulting amine linkage is non-degradable in vivo.
Because many drugs such as proteins have amine groups that are readily available for reaction to form linkages, it is desirable to make such linkages hydrolytically degradable so that free proteins or other amine-containing agents can be released from the prodrugs at a controlled rate in vivo. Imines, or Schiff bases, offer a possible approach since they hydrolyze to generate the free amine and an aldehyde:
where Rxe2x80x2 is a drug or other agent bearing an amino group. This approach has been used in attaching doxorubicin to PEG with release of the drug occurring by hydrolysis of the imine linkage. Ouchi et al. Polymer Preprints 38(1):582-3 (1997). Since the formation of imines is reversible in water, these compounds are best prepared in organic solvents. Many proteins, peptides, and other agents are thus not amenable to the imine prodrug approach because of their poor solubility or instability in organic solvents.
Conjugates can be prepared by linking an amine-containing drug, through a non-hydrolyzable amide or carbamate linkage, to a PEG molecule having hydrolytically degradable linkages in the PEG backbone. The amine-containing drug is releasable upon the degradation of the PEG backbone. However, the released drug usually has a fragment attached through an amide or carbamate linkage, and the native or parent drug is not released.
U.S. Pat. No. 4,935,465 discloses a water-soluble prodrug in which neighboring group participation by a carboxyl group aids in the hydrolysis of an amide, thus releasing the drug. PEG was a component of a bovine serum albumin (BSA) prodrug disclosed in that patent:
U.S. Pat. No. 5,561,119 and European Patent No. 595133-A disclose a doxorubicin prodrug as shown below, which utilizes a benzylglucuronyl carbamate linkage. A second component, glucuronidase, must be added in order to cleave the glucuronic acid and liberate doxorubicin and a nitrobenzoquinone methide.
In yet another approach as disclosed in U.S. Pat. No. 5,413,992, a prodrug of daunamycin shown below, liberates the native drug by an enzyme-induced elimination initiated by abstraction of a proton adjacent to the sulfone group.
In addition, U.S. Pat. No. 4,760,057 describes enzymatic hydrolysis of a prodrug containing a carbamate linkage:
RRxe2x80x2NCO2CR1R2O2CR3
where RRxe2x80x2N represents the secondary amine on a drug moiety, and R1-3 are various moieties such as hydrogen, alkyls, or cycloalkyls. Such prodrugs are hydrolyzed by esterases to generate RRxe2x80x2NCO2CR1R2OH which then decomposes to liberate the drug agent.
Greenwald et al. J. Med. Chem., 42:3657-3667 (1997) discloses prodrugs having a drug linked, through a carbamate linkage to a PEG derivative. 1,4 or 1,6 elimination reaction is required to release the free drug. The prodrug is structurally complex and toxic quinone methide intermediates may be liberated along the free drug.
Thus, the prodrugs in the prior art generally have drawbacks that limit their practical applications. The requirement for enzyme digestion makes the prodrugs unsuitable or at least less useful for in vivo use. In addition, the generation of toxic intermediates can be associated with the release of free drugs. Thus, there remains a need for prodrugs having improved characteristics.
The invention provides a water soluble prodrug in which a biologically active agent is linked to a water soluble non-immunogenic polymer by a hydrolyzable carbamate bond. The biologically active agent can be readily released by the hydrolysis of the carbamate bond in vivo without the need for adding enzymes or catalytic materials. Generally, the biologically active agent is released, upon hydrolysis, into its parent state, i.e., without any additional moieties attached thereto. In addition, because a water soluble, non-peptidic polymer is used, even a substantially insoluble biologically active agent can be readily delivered in the prodrug in vivo.
Thus, in accordance with the present invention, a prodrug is provided having the formula:
wherein POLY is a water soluble and non-peptidic polymer, L is a linking group, Ar is an aromatic group, and Y is a biologically active agent.
The water soluble non-immunogenic polymer can have a capping group selected from the group consisting of OH, alkoxy, and
wherein Lxe2x80x2 is a linking group, Arxe2x80x2 is an aromatic group, and Yxe2x80x2 is a biologically active agent. Preferably, POLY is a poly(ethylene glycol) or a derivative thereof having a molecular weight of from about 200 to about 100,000 Daltons.
In accordance with another embodiment of the invention, a compound is provided having the formula:
in which POLY is a water soluble, non-peptidic polymer, L is a linking group, Ar is an aromatic group, and X is an activating group capable of reacting with an amino group of a biologically active agent to form a carbamate linkage.
Optionally, POLY can have a capping group selected from the group consisting of OH, alkoxy, and
wherein Lxe2x80x2 is a linking group, Arxe2x80x2 is an aromatic group , and Xxe2x80x2 is an activating group capable of reacting with an amino group of a biologically active agent to form a carbamate linkage. Preferably, POLY is a poly(ethylene glycol) or a derivative thereof having a molecular weight of from about 200 to about 100,000 Dalton.
In another embodiment of this invention, a prodrug is provided having the formula:
Yxe2x80x94Arxe2x80x94Oxe2x80x94C(O)xe2x80x94NH-POLY
where Y is a biologically active agent having an aromatic group, Ar is the aromatic group of the biologically active agent Y, such as a substituted benzene or other aromatic such as a substituted naphthalene or heterocylic moiety, and POLY is a water soluble, non-peptidic polymer, preferably poly(ethylene glycol) in any of its form. Hydrolysis of this derivative yields the parent drug Yxe2x80x94ArOH, and POLY-NH2 and CO2.
In accordance with yet another embodiment of the present invention, a hydrolytically degradable hydrogel is provided. The hydrogel comprises a backbone bonded to a crosslinking agent through a hydrolyzable carbamate linkage. Typically, a suitable backbone can be any compound having an amino group, preferably at least two amino groups. Examples of such backbones include, but are not limited to, proteins, peptides, aminocarbohydrates, aminolipids, poly(vinylamine), polylysine, poly(ethylene glycol) amines, pharmaceutical agents having an amino group, etc. The crosslinking agent is selected from the group consisting of:
wherein POLY is a non-peptidic, water soluble polymer, L and Lxe2x80x2 are linking groups, Ar and Arxe2x80x2 are aromatic groups, Z is a central branch core, n is from 2 to about 100, and X and Xxe2x80x2 are activating groups capable of reacting with the amino groups in the backbone to form hydrolyzable carbamate linkages. Preferably, POLY is a poly(ethylene glycol) or derivative thereof having a molecular weight of from about 200 to about 100,000.
The foregoing and other features and advantages of the invention, and the manner in which the same are accomplished, will be more readily apparent upon consideration of the following detailed description of the invention in conjunction with the claims and the drawings. | {
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The food service industry needs to manage the high number of soiled dishes encountered on a daily basis. The food service industry includes restaurants and numerous institutional food service establishments present in schools, prisons, municipal buildings, military mess halls, and the like.
In such food service industry establishments, the warewashing process typically begins with scraping of dishes into a garbage can or other refuse container. Scraping is performed to remove the larger scraps of food and the like. Following scraping, pre-rinse sprayers are used to rinse the dishes prior to placement of the dishes into commercial warewashing machines.
The commercial warewashing machine market is different that of most other commercial food service equipment markets. Warewashing machines often are not owned by the individual restaurant or food service operator. Rather, warewashing machines are leased to the individual restaurant or food service operator by a chemical sales company. As a term of many leases, the food establishment is not able to modify, service or repair the warewashing machine. Rather, the food establishment is simply able to use the machine to wash the dishes. | {
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The invention relates to a lining part, particularly to a door-lining carrier, for a motor vehicle, preferably of foamed plastic.
Such lining parts, especially the door-lining carriers addressed above, are manufactured in the automobile industry from various materials such as molded fiber-containing materials, flax/sisal bonded in resin, HM polypropylene, hard polyurethane foam with fiberglass or glass mats, as well as of thermoplastic materials. At the surface, these carriers have a decor on which the adhesive is placed or which is connected directly with the carrier.
The weight of all these lining parts is high and there is a lack of integrated protection zones in the event of an impact from the side. Aside from a lack of additional thermal insulation and sound protection, many of them absorb water up to an amount of 40% by weight. With the passage of time, this leads not only to a destruction of the lining part, but also to an appreciable increase in the total weight of the vehicle. | {
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1. Field of the Invention
The invention generally relates to light bulbs and more particularly relates to a LED wedge light bulb system.
2. Description of Related Art
Light bulbs, such as T-10 style light bulbs and LED's, have been well known in the art and available in the market place for quite sometime. Generally, in the prior art, a wedge bulb is only the light bulb portion of a lighting system. Some prior art LED light bulbs require a base to mount to a circuit board in order to emit light in a predetermined direction and color. Generally, these prior art LED bulb bases are a twist in style base with metal connectors, which carry the current to the light bulb for use in lighting the LED style light bulb. It should be noted that these prior art T-10 wedge light bulbs generally have low power consumption and ultra long life and may be used in any known lighting application, but generally are used for replacement of turn signal lights, corner lights, parking lights, side marker lights, tail lights, backup lights, etc., and may be used in the automotive, marine or aviation vehicle industries. These prior art LED light bulbs may be compatible to numerous socket and bulb models, such as but not limited to T-10, 194, W5W, 147, 152, etc. It should be noted that generally these wedge style prior art LED light bulbs use SMD panels or surface mounted devices to form the light bulbs. These surface mounted devices (SMD) generally have pixels that consist of red, green and blue diodes mounted into a single package, which is then mounted on a driver PC board. It should be noted that the individual diodes in some prior art LED bulbs are smaller than a pin head and are set very close together. It should also be noted that conventional or discrete LED's may also be used in prior art LED bulb technologies.
Therefore, there is a need in the art for an improved LED SMD light bulb system. There also is a need in the art for an LED SMD light bulb system that is easier to connect to the lighting system. There also is a need in the art for a more reliable LED SMD style light bulb that may assure proper alignment between metal contactors and the circuit boards, components, or receptacles carrying the LEDs. There also is a need in the art for a more robust LED SMD light bulb system that may not vibrate out of a wedge base during use in a vehicle. There also is a need in the art for a one piece design or system for a LED light bulb and base integrated with one another. | {
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1. Field of the Invention
The present invention relates generally to integrated circuit comparators, and, more particularly, to integrated circuit comparators for use in low voltage applications.
2. Description of the Related Art
A conventional CMOS voltage comparator 10 is illustrated in FIG. 1. The CMOS voltage comparator 10 includes a differential amplifier II and an inverter 12. A reference voltage VR is applied to one input of the differential amplifier 11, i.e., a gate terminal of a transistor 21, and an input voltage V1 to be compared to the reference voltage is applied to another input to the differential amplifier 11, i.e., a gate terminal of a transistor 22. In operation, when the input voltage V1 becomes higher than the reference voltage VR, an output signal on a line 25 switches from a low voltage, for example, a logic level xe2x80x9czero,xe2x80x9d to a high voltage, for example, a logic level xe2x80x9cone.xe2x80x9d When the input voltage V1 becomes lower than the reference voltage VR, the transistor 22 turns off, the input signal to the inverter 12 becomes high, and the output signal VOUT changes from a high state to a low state. In this manner, the input voltage V1 is compared to the reference voltage VR. Ideally, the transition between logic levels at the output line 25 will occur when V1 is equal to VR, there being no offset voltage. Also ideally, the transition between logic levels will occur with no time delay, the speed of the comparator 10 being very fast. These ideals are rarely, if ever, attained.
Comparators are widely used in integrated circuits, for example, in analog-to-digital converters and as voltage signal receivers on interconnections and clock distribution lines. Two primary concerns in the application of comparators are the mismatch of transistor characteristics, resulting in voltage offsets, and the speed of operation, or time delay in operation. Because one of the basic components of a comparator is a differential amplifier, which typically involves three transistors coupled in series, operation of the comparator becomes slower and less reliable as power supply voltages are reduced. Lower power supply voltages result in lower magnitudes of the excess of gate voltage above the threshold voltage of the MOS transistors. The switching current, or saturation current, depends upon the square of this excess gate voltage:
Ids=(uCo) (W/L) (VGSxe2x88x92VT)2/2
The time, t, required to discharge a capacitor with charge Q can be estimated as:
t=Q/Ids
If the excess of gate-to-source voltage above threshold (VGSxe2x88x92VT) is small, the delay time will be long, and the circuits will operate at low switching speeds.
The inverter 12 of FIG. 1 is a conventional single-ended input, single-ended output, CMOS amplifier. To illustrate the operation of the inverter amplifier 12, assume a power supply potential 26 is 1.6 volts, i,e., VDD equals 1.6 volts DC. Assume further that the quiescent input and output voltages are at VDD/2, or 0.8 volts DC. Both the PMOS transistor 28 and the NMOS transistor 30 are assumed, for purposes of illustration, to have matching characteristics and matching threshold voltages of 0.5 volts. That is, VTN equals 0.5 volts, and VTP equals xe2x88x920.5 volts. In practice, different sizes or W/L ratios can be used to compensate for the fact that the transistors do not have matching characteristics. Assuming the stated values, the turn-on time for the inverter amplifier 12 is approximately three nanoseconds, whereas, the turn-off time for the inverter amplifier 12 is on the order of tens of nanoseconds.
Low switching speeds and circuit functional failure at low power supply voltages are even more acute in differential amplifiers that form part of a comparator circuit, such as the comparator circuit 10 of FIG. 1. In the differential amplifier 11 of the comparator circuit 10 of FIG. 1, three devices, transistors 21, 23, 24, are coupled in series between the power supply potential 26 and the power supply ground 29. Also, three other transistors 22, 24, 27 are coupled in series between the power supply potential 26 and the power supply ground 29. Each of the transistors 21, 22, 23, 24, 27 needs a reasonable magnitude of excess gate voltage above threshold to operate properly. With the power supply potential 26 equal to 1.5 volts DC, the turn-on time for the comparator 10 is just over one nanosecond, while the turn-off time is on the order of 3-4 nanoseconds. When the power supply potential 26 is dropped to 1.2 volts DC, the turn-on time lengthens to approximately 4 nanoseconds, while the turn-off time lengthens to approximately 6 nanoseconds. When the power supply potential 26 is dropped even further, to 0.9 volts DC, the turn-on time for the comparator 10 is again approximately 4 nanoseconds, but the turn-off time approaches 10 nanoseconds, becoming so long that the comparator 10 begins to function incorrectly.
The present invention is directed to eliminating, or at least reducing the effects of, some or all of the aforementioned problems.
In one aspect of the present invention, an integrated circuit comparator comprises a differential amplifier, a source follower circuit coupled to a gate terminal of a first transistor in the differential amplifier, and an output circuit. A single or multiple source follower circuits may be utilized as desired.
In another aspect of the present invention, an integrated circuit comparator comprises a differential amplifier, a first power supply line coupled to the differential amplifier, the first power supply line adapted to receive a positive power supply potential of approximately 0.9 volts, a source follower circuit coupled to a gate terminal of a first transistor in the differential amplifier, and an output circuit. A single or multiple source follower circuit may be utilized as desired.
In yet another aspect of the present invention, a differential amplifier comprises first and second transistors coupled in electrical series between a first node and a second node, third and fourth transistors coupled in electrical series between the first node and the second node, and a source follower circuit coupled to a gate terminal of the first transistor, the second transistor adapted to receive a first input signal, and the fourth transistor adapted to receive a second input signal.
In yet another aspect of the present invention, a low voltage amplifier comprises a first transistor and a second transistor coupled in electrical series between first and second power supply nodes, a source follower circuit coupled to a gate terminal of the first transistor, and an input line coupled to the source follower circuit and coupled to a gate terminal of the second transistor.
In another aspect of the present invention, a low voltage amplifier comprises first and second transistors coupled in electrical series between first and second power supply nodes, a third transistor coupled between the first power supply node and a gate terminal of the first transistor, a current source device coupled between the gate terminal of the first transistor and the second power supply node, and an input node coupled to a gate terminal of the third transistor and to a gate terminal of the second transistor. | {
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1. Technical Field
The present invention relates to a stack of absorbent articles for absorption of body fluids, each article being individually wrapped.
2. Background Art
Absorbent articles for personal hygiene, especially those articles which are intended to be worn inside ordinary briefs and are in this connection fitted in the briefs by the user personally, are often single-wrapped. Single wrapping means that each absorbent article is packed in a wrapping cover. In this way, it is simple for the user, in an easy and hygienic manner, to carry one or more absorbent articles, for example in a handbag. Examples of the type of absorbent article concerned are sanitary towels, panty liners and incontinence pads for people with mild to moderate incontinence.
The most common way of single-wrapping absorbent articles is by folding them together into a smaller size, after which they are packed in a thin wrapping cover made of plastic or paper. Such a wrapping cover often consists of a rectangular piece of material, which has been folded twice in its transverse direction and subsequently joined together along its side edges so that a bag-like container for the absorbent article is formed, and also a lid part which can close the container. In the closed state of the wrapping cover, the lid part is frequently fastened in the edge joins on the outside of the container part by releasable joins, such as breakable welds or releasable glue. There can also be further sealing between the lid part and the container part along the end edge of the lid part. Such sealing can be in the form of, for example, releasable glue, hook and loop means, tape flaps or the like. If the sealing means allows resealing, it can also be used for closing the wrapping cover if it is used for wrapping up an absorbent article after use.
It has been found, however, that the known single wrappings can be difficult to open. As the wrapping material is thin and flexible, the lid part will come to lie close to the outside of the container part. This problem is accentuated by the fact that absorbent articles of the type concerned here are packed with a large number of individually wrapped articles in a larger outer packing. In this connection, the articles are pressed together with a fair degree of force, the wrapping covers also being subjected to being pressed together, which of course means that the lid part of the wrapping cover is pressed against the outside of the container part. Owing to the strong compression of the wrapping material and the fact that the wrapping material is usually very thin and flexible, it has become apparent that many users find it difficult to grip the edge of the lid part so that the wrapping cover can be opened. It can be very difficult both to discern the edge visually and to feel where it is with the fingers. This is clearly a particular problem for people with impaired vision or with limited manual dexterity. As the occurrence of incontinence increases with increasing age, as do vision problems and problems of poor mobility and/or feeling in the hands, handling of the known single wrappings is therefore a common and particularly irritating problem especially for older users of absorbent articles. | {
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Mycobacteria are a significant cause of morbidity and mortality, particularly among immunocompromised or elderly individuals and in countries with limited medical resources. Ninety-five percent of human infections are caused by seven species: Mycobacterium tuberculosis, M. avium (also known as the mycobacterium avium complex or M. avium-intracellulare), M. leprae, M. kansasii, M. fortuitum, M. chelonae, and M. abscessus. The most common mycobacterial infections in the United States are pulmonary infections by M. tuberculosis or M. avium. Such mycobacterial infections have been of increasing concern over the past decade, particularly in light of the increasing incidence of multi-drug resistant strains.
Mycobacterium tuberculosis (Mtub) is the causative agent of the disease tuberculosis in humans. Estimates indicate that one-third of the world's population, including 10 million in the U.S., are infected with M. tuberculosis, with 8 million new cases and 3 million deaths reported world wide each year. Although incidence of tuberculosis steadily decreased since the early 1900s, this trend changed in 1984 with increased immigration from endemic countries and increased infection among homeless individuals, drug and alcohol abusers, prisoners, and HIV-infected individuals. The increasing occurrence of drug-resistant strains requires continued research into new and more effective treatments.
M. avium infection poses the greatest health risk to immunocompromised individuals, and is one of the most common opportunistic infections in patients with AIDS (Horsburgh (1991) New Eng. J. Med. 324:1332-1338). In contrast with disease in other patients, M. avium infection can be very serious in immunocompromised individuals (e.g., AIDS patients, who have a low CD4+ T-cell count (Crowe, et al. (1991) J. AIDS 4:770-776)), and can result in disseminated infection in which virtually no organ is spared.
Treatment of mycobacterial infections is complicated and difficult. For example, treatment of M. tuberculosis and of M. avium infections requires a combination of relatively toxic agents, usually three different drugs, for at least six months. The toxicity and intolerability of these medications usually result in low compliance and inadequate treatment, which in turn increases the chance of therapeutic failure and enhances the selection for drug-resistant organisms. Treatment of mycobacterial infections is further complicated in pregnant women, patients with pre-existing liver or renal diseases, and immunocompromised patients, e.g., AIDS patients.
Sulfotransferases are enzymes that catalyze the transfer of a sulfate from a donor compound to an acceptor compound, usually placing the sulfate moiety at a specific location on the acceptor compound. In mycobacteria, the most notable sulfated compounds identified to date are the “sulfatides” of Mtub. Sulfatides are a closely related set of sulfated glycolipids. They are characterized by a common trehalose-2-sulfate core disaccharide. Sulfatide-1 (sulfolipid-1 or SL-1), the most abundant of the sulfatides, has been extensively studied both structurally and biologically. The molecule consists of a 2,3,6,6′-tetra-O-acyl-trehalose-2′-sulfate. Other members of the family differ in the number and type of the acyl substituents, but not in the core sulfated disaccharide. Reported biological properties of the purified SL-1 include its ability to inhibit macrophage phagosome/lysosome fusion, to enhance the secretion of TNF-α, to inhibit macrophage priming, and to activate human neutrophils.
Recently, a second set of sulfated structures have been identified and characterized in Mycobacteria. A sulfate group has been found in an ester linkage to a sugar residue of a mycobacterial glycopeptidolipid (GPL), in one case at the 2-position of a 3,4-di-O-methylrhamnose in the GPL of M. fortuitum, and in another case at the 4-position of a 6-deoxy-talose in a GPL of a drug-resistant strain of M. avium.
To date, numerous virulence factors and potential drug targets have been studied in Mtub and M avium (Mav). No single genetic or metabolic entity, however, has yet to be identified as solely or even mostly responsible for the organisms' ability to cause disease in humans. In particular, information regarding the enzymes responsible for synthesizing sulfated macromolecules in mycobacteria is needed. As such, there is continued interest in identifying additional genes and gene products in Mycobacterium species that can serve as diagnostic tools, and as targets for therapeutic intervention.
Literature Bloom and Murray (1999) Science 257:105-1064 Daffe and Draper (1998) Adv. Microb. Physiol. 39:149-152; Hemmerich and Rosen (2000) Glycobiol. 10:848-856; Goren et al. (1976) Proc. Natl. Acad. Sci. USA 73:2510-2514; Bronzna et al. (1991) Infect. Immun. 59:2542-2548; Pabst et al. (1988) J. Immunol. 140:634-640; Zhang et al. (1991) J. Immunol. 146:2730-2736; Lopez Marin et al. (1992) Biochem. 31:11106-11111; Khoo et al. (1999) J. Biol. Chem. 274:9778-9785; Tsukamara and Mizuno (1981) Microbiol. Immunol. 25:215; Cole et al. (1998) Nature 393:537-544; U.S. Pat. No. 6,046,002. | {
"pile_set_name": "USPTO Backgrounds"
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Field of the Invention
One disclosed aspect of the embodiments relates to an electromechanical transducer and a method of producing the transducer. More specifically, one embodiment relates to an electromechanical transducer that is used as an ultrasonic transducer and a method of producing the transducer.
Description of the Related Art
A capacitive electromechanical transducer produced by micromachining technology has been being researched as a substitute for piezoelectric devices. In the capacitive electromechanical transducer, charging of an insulating film constituting an element changes the effective voltage applied between opposing electrodes, and thereby the conversion efficiency varies. The conversion efficiency herein is the efficiency of converting vibration of a vibration film into an electrical signal. The conversion efficiency is increased with an increase in the voltage applied or with a decrease in the distance between the electrodes. The variations among the cells or the elements in conversion efficiency cause variations in sensitivity and bandwidth of the electromechanical transducer.
Japanese Patent Laid-Open No. 2008-288813 describes an electromechanical transducer in which the charge storage (charging) of an insulating film disposed between electrodes is prevented and, at the same time, the pressure resistance of the insulating film between the upper and lower electrodes is improved. In the electromechanical transducer described in Japanese Patent Laid-Open No. 2008-288813, the insulating film being in contact with the lower electrode is a silicon oxide film, and the insulating film (membrane) being in contact with the upper electrode on the space side is also a silicon oxide film. Silicon oxide films hardly accumulate charge, and thereby such a configuration may prevent charging. In addition, a silicon nitride film is disposed between the lower electrode and the upper electrode. The silicon nitride film has a higher relative dielectric constant than that of the silicon oxide film and therefore may have a larger thickness for providing the same capacitance as an insulating film. Accordingly, such a configuration may enhance the dielectric strength.
However, the silicon oxide film has compression stress. In the case of using a silicon oxide film as the membrane that is in contact with the upper electrode on the space side for preventing charging, as in Japanese Patent Laid-Open No. 2008-288813, the vibration film is highly bent due to, for example, buckling. If the bending amount is large, the vibration film may be broken in some cases. In the case of a silicon oxide film, the degree of bending of the vibration film also tends to vary among cells or elements. The variation among the vibration films in bending causes a variation among the elements in sensitivity. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a magnetic recording apparatus and in particular, to a magnetic recording apparatus for recording and reproducing data with comparatively high density. The present invention also relates to a head error detection apparatus for detecting an error caused by a magnetic head for writing and in particular, to a program product for detecting a head error.
2. Description of the Related Art
Conventionally, a magnetic recording apparatus comprises a head drive circuit including a head error detection circuit for detecting a head error such as a write magnetic head disconnection and a short-circuit.
In general, the head error detection circuit detects a voltage level of reverse electromotive force pulse generated at a head current switching and compares the value detected with a reference value. When a head error such as disconnection and short-circuit is caused, the voltage level of the reverse electromotive force pulse does not reach the reference value. Upon detection of this small voltage, the error detection circuit generates a fault pulse signal, which causes a magnetic recording apparatus to enter an interrupt mode in which no data recording is carried out.
The head error detection circuit executes a write unsafe (WUS) check. A WUS check circuit has an inherent frequency characteristic and cannot operate in response to a frequency above a predetermined frequency band. Moreover, WUS check circuits of an identical type may differ in the frequency characteristic. To cope with this, in general, a head portion of a data area contains a signal of a single frequency, i.e., xc2xd or ⅓ of the maximum frequency, and the area where this signal is written serves as an object of the WUS check. This area to be checked will be referred to as a xe2x80x9cWUS check areaxe2x80x9d.
Explanation will be given of a conventional head error detection circuit disclosed in Japanese Patent Publication (Unexamined) No. A-4-313864. In this circuit a recording current is reduced because an apparatus using this circuit has a high efficiency, low-floating head. This results in a low frequency data write which is normal but regarded as an error. To cope with this, the aforementioned head detection circuit changes the area subjected to the write unsafe (WUS) check. This prevents a malfunction and enables correct execution of the WUS check.
These years, the magnetic recording apparatus has increased its data transfer rate and write frequency, which in turn requires strict conditions of overwrite and non-linear bit shift. Accordingly, depending on the recording frequency, the head error detection circuit has a higher sensitivity, which increases the frequency of malfunctions caused by a noise overlaid in a power source and grinding line or inductance. If the head error detection circuit operates incorrectly, an error is detected and a write operation is interrupted even when the apparatus is in a normal state.
It is therefore an object of the present invention to provide an improved magnetic recording apparatus capable of preventing a malfunction to decide a normal apparatus as an error.
Another object of the present invention is to provide a magnetic recording apparatus capable of carrying out a stable recording operation, irrespective of the recording frequency change.
In the magnetic recording apparatus according to the present invention, when a head error is detected, a data write is retried with a recording frequency different from a normal recording frequency. More specifically, the data write is retried with a recording frequency higher or lower than the normal recording frequency. If no error is detected in this retrial, a write operation is resumed in a data area. This prevents incorrect an decision that the apparatus which should be normal is not in a normal state. Moreover, it is possible to carry out, at a write check or apparatus rise, a data write with a recording frequency different from a normal recording frequency, irrespective of a head error. | {
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The instant invention relates generally to waste containers and more specifically it relates to a trash separation receptacle. Numerous waste containers have been provided in prior art that are adapted to receive refuse material, so that the refuse material can be disposed of. For example, U.S. Pat. Nos. 4,593,615 to Kehl; 4,834,262 to Reed; 4,729,489 to Papaianni; 4,867,328 to McCarthy; 4,913,308 to Culbertson and 4,955,495 to Ruebesam all are illustrative of such prior art. While these units may be suitable for the particular purpose to which they address, they would not be as suitable for the purposes of the present invention as heretofore described. | {
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The loudspeaker amplifier in a line-powered loudspeaking telephone is easily excited to maximum level due to only limited power being available from the telephone network. This causes distortion, which is often already noticeable at normal speech levels and which can be heavy for high speech levels.
Simple and cheap loudspeaker elements usually have small diaphragm masses and small magnet systems, which give low mechanical attenuation and thereby a high Q-value. The efficiency of such loudspeaker elements is considerably higher for frequencies in the vicinity of the resonance frequency than for higher and lower frequencies. In the utilisation of such loudspeaker elements, a large part of the acoustic effect must therefore be attenuated with the aid of suitable absorbents in a sealed loudspeaker box so that the resulting efficiency will be relatively uniform. It will also be rather low, however. It is therefore generally the case in loudspeaking telephones to use expensive loudspeaker elements with relatively uniform efficiency. However, here also the elements must be mounted conventionally in a closed box with absorbents for attenuating resonances. | {
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I. Field of the Invention
The present invention relates to a system and methods generally aimed at surgery. More particularly, the present invention is directed at a system and related methods for performing surgical procedures and assessments involving the use of neurophysiology.
II. Description of Related Art
A variety of surgeries involve establishing a working channel to gain access to a surgical target site. Oftentimes, based on the anatomical location of the surgical target site (as well as the approach thereto), the instruments required to form or create or maintain the working channel may have to pass near or close to nerve structures which, if contacted or disturbed, may be problematic to the patient. Examples of such “nerve sensitive” procedures may include, but are not necessarily limited to, spine surgery and prostrate or urology-related surgery.
Systems and methods exist for monitoring nerves and nerve muscles. One such system determines when a needle is approaching a nerve. The system applies a current to the needle to evoke a muscular response. The muscular response is visually monitored, typically as a shake or “twitch.” When such a muscular response is observed by the user, the needle is considered to be near the nerve coupled to the responsive muscle. These systems require the user to observe the muscular response (to determine that the needle has approached the nerve). This may be difficult depending on the competing tasks of the user. In addition, when general anesthesia is used during a procedure, muscular response may be suppressed, limiting the ability of a user to detect the response.
While generally effective (although crude) in determining nerve proximity, such existing systems are incapable of determining the direction of the nerve to the needle or instrument passing through tissue or passing by the nerves. This can be disadvantageous in that, while the surgeon may appreciate that a nerve is in the general proximity of the instrument, the inability to determine the direction of the nerve relative to the instrument can lead to guess work by the surgeon in advancing the instrument and thereby raise the specter of inadvertent contact with, and possible damage to, the nerve.
Another nerve-related issue in existing surgical applications involves the use of nerve retractors. A typical nerve retractor serves to pull or otherwise maintain the nerve outside the area of surgery, thereby protecting the nerve from inadvertent damage or contact by the “active” instrumentation used to perform the actual surgery. While generally advantageous in protecting the nerve, it has been observed that such retraction can cause nerve function to become impaired or otherwise pathologic over time due to the retraction. In certain surgical applications, such as spinal surgery, it is not possible to determine if such retraction is hurting or damaging the retracted nerve until after the surgery (generally referred to as a change in “nerve health” or “nerve status”). There are also no known techniques or systems for assessing whether a given procedure is having a beneficial effect on a nerve or nerve root known to be pathologic (that is, impaired or otherwise unhealthy).
In spinal surgery, and specifically in spinal fusion procedures, a still further nerve-related issue exists with regard to assessing the placement of pedicle screws. More specifically, it has been found desirable to detect whether the medial wall of a pedicle has been breached (due to the formation of the hole designed to receive a pedicle screw or due to the placement of the pedicle screw into the hole) while attempting to effect posterior fixation for spinal fusion through the use of pedicle screws. Various attempts have been undertaken at assessing the placement of pedicle screws. X-ray and other imaging systems have been employed, but these are typically quite expensive and are oftentimes limited in terms of resolution (such that pedicle breaches may fail to be detected).
Still other attempts involve capitalizing on the insulating characteristics of bone (specifically, that of the medial wall of the pedicle) and the conductivity of the exiting nerve roots themselves. That is, if the medial wall of the pedicle is breached, a stimulation signal (voltage or current) applied to the pedicle screw and/or the pre-formed hole (prior to screw introduction) will cause the various muscle groups coupled to the exiting nerve roots to twitch. If the pedicle wall has not been breached, the insulating nature of the medial wall will prevent the stimulation signal from innervating the given nerve roots such that the muscle groups will not twitch.
To overcome this obviously crude technique (relying on visible muscles twitches), it has been proposed to employ electromyographic (EMG) monitoring to assess whether the muscle groups in the leg are innervating in response to the application of a stimulation signal to the pedicle screw and/or the pre-formed hole. This is advantageous in that it detects such evoked muscle action potentials (EMAPs) in the leg muscles as much lower levels than that via the “visual inspection” technique described above. However, the traditional EMG systems employed to date suffer from various drawbacks. First, traditional EMG systems used for pedicle screw testing are typically quite expensive. More importantly, they produce multiple waveforms that must be interpreted by a neurophysiologist. Even though performed by specialists, interpreting such multiple EMG waveforms in this fashion is nonetheless disadvantageously prone to human error and can be disadvantageously time consuming, adding to the duration of the operation and translating into increased health care costs. Even more costly is the fact that the neurophysiologist is required in addition to the actual surgeon performing the spinal operation.
The present invention is directed at eliminating, or at least reducing the effects of, the above-described problems with the prior art. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a compound containing 5-membered heterocycles, an organic electronic device using the same, and a terminal including the latter.
2. Description of the Prior Art
In general, an organic light emitting phenomenon indicates conversion of electric energy into light energy by means of an organic material. An organic electronic device using the organic light emitting phenomenon generally has a structure including an anode, a cathode, and an organic material layer interposed therebetween. Herein, in many cases, the organic material layer may have a multi-layered structure having respective different materials in order to improve efficiency and stability of an organic electronic device. For example, it may include a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and the like.
Materials used as an organic material layer in an organic electronic device may be classified into a light emitting material and a charge transport material, for example, a hole injection material, a hole transport material, an electron transport material, an electron injection material, etc. according to their functions. Then, the light emitting material may be divided into a high molecular weight type and a low molecular weight type according to their molecular weight, and may be divided into a fluorescent material from electronic singlet excited states and a phosphorescent material from electronic triplet excited states according to their light emitting mechanism. Further, the light emitting material can be classified into a blue, green or red light emitting material and a yellow or orange light emitting material required for giving a more natural color, according to a light emitting color.
Meanwhile, when only one material is used as a light emitting material, an efficiency of a device is lowered owing to a maximum luminescence wavelength being moved to a longer wavelength due to the interaction between the molecules, the deterioration of color purity and the reduction in light emitting efficiency. Therefore, a host/dopant system can be used as the light emitting material for the purpose of enhancing the color purity and the light emitting efficiency through energy transfer. It is based on the principle that if a small amount of a dopant having a smaller energy band gap than a host forming a light emitting layer is mixed with the light emitting layer, excitons which are generated in the light emitting layer are transported to the dopant, thus emitting a light having a high efficiency. Here, since the wavelength of the host is moved according to the wavelength of the dopant, a light having a desired wavelength can be obtained according the kind of the dopant.
In order to allow the organic electronic device to fully exhibit the above-mentioned excellent characteristics, a material constituting the organic material layer in the device, for example, a hole injection material, a hole transport material, a light emitting material, an electron transport material and an electron injection material should be essentially composed of a stable and efficient material. However, the development of a stable and efficient organic material layer material for the organic electronic device has not yet been fully realized. Accordingly, the development of new materials is continuously desired. | {
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Multiview displays are operable to display multiple views of an image. The views are directed to different locations within a viewing area. A multiview display can be used to generate a three-dimensional (3D) visual effect by displaying two or more views to a person viewing the display (i.e. viewer or observer) to create the perception of depth. For example, left and right views representing different perspectives of a scene or object may be directed to the left and right eyes of the viewer, respectively. As the views are spatially separated, the viewer does not need to wear viewing eyeglasses to view the left and right images displayed by a multiview display.
Some multiview displays can display two views (e.g. left and right views). Such displays may be suitable for viewing by a single viewer. Other multiview displays can display more than two views. Such multiview displays can repeat sets of left and right views over a range of viewing positions within the viewing area so that the same 3D image can be observed by a viewer located at one of the viewing positions. In other cases, multiview displays can display images representing different perspectives of a scene or object so that a viewer observes the scene or object from different perspectives when moving from place to place.
A multiview display may be constructed from a flat panel display or projection display having a light source, such as, for example, a liquid crystal display (LCD), digital light projector (DLP) display, liquid crystal on silicon (LCOS) display, organic light-emitting diode (OLED) display, high-dynamic range (HDR) display, plasma display, or the like. An optical layer or filter may be provided with such displays to direct light for an image to different locations in the viewing area. In some multiview displays the optical layer comprises a parallax barrier which blocks light in particular directions so that for a given viewing angle only certain parts of the image can be viewed. In other multiview displays the optical layer comprises a plurality of micro-lenses (e.g. lenticular lenses) for refracting the light. The lenses may be adapted to direct the light to different locations along a horizontal direction, or along horizontal and vertical directions, for example.
Some multiview displays have an optical layer comprising active optical steering elements (e.g. switchable parallax barrier, displaceable lenses, and the like). An example of such a display is described by Goulanian et al. in US Patent Application Publication No. 2007/0165013 titled “Apparatus and System for Reproducing 3-Dimensional Images.”
In addition to the above-noted technologies, other technologies exist for directing light in particular directions to display multiple views within a viewing area.
A problem that the inventors have identified in relation to multiview displays is that increasing the number of views may lead to a degradation of the image quality given the display constraints. It is desirable to provide a multiview display system which can be adapted for different viewing circumstances. Such adaptable displays may provide improved viewing experiences to viewers.
It is also desirable to provide a multiview display that is energy efficient.
The foregoing examples of the related art and limitations related thereto are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings. | {
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The present invention relates generally to damping spacers for overhead parallel conductors and particularly to a damping spacer having a variable damping characteristic that is effective to dampen aeolian vibrations in both low and high temperature environments as well as wake-induced oscillations that occur in conductor bundles.
A properly designed damping spacer for overhead conductor bundles should be capable of controlling two major forms of conductor motion, namely, an aeolian vibration and a wake-induced oscillation of one or more of the bundle conductors. respectively. aeolian vibration is a conductor motion of relatively high frequency and low amplitude; it results from smoothly flowing winds moving at velocities of 2 to 15 miles per hour. Wake-induced oscillation, on the other hand, comprises motion of a relatively low frequency and large and sometimes clashing amplitudes. This type of motion is peculiar to bundle conductors and arises from the effects of the shielding of the leeward conductor by the windward conductor. The wake-induced phenomena is discussed in U.S. Pat. Nos. 3,925,594 and 4,018,980 to Rawlins and Mohajery et al, respecively.
The design of an elastomer damping spacer for damping aeolian vibration is complicated by the effects of changes in temperature; i.e., when the temperature falls, the material of the damping elastomer tends to harden such that it is less amenable to working by the low energy of aeolian motion. For this reason the design of the spacer and the material of the damping element should provide a characteristic that is "soft" so that aeolian vibration is damped in the worst case, i.e., at the lowest anticipated cold weater condition. And for this reason such softness is ineffective as a damping mechanism when there is high energy input to the conductor under conditions of wake-induced oscillation.
In U.S. Pat. No. 4,223,176 to Hawkins, a damping spacer is shown in which damping elements are protected from the ultraviolet degradation of the sun by a hub interlock structure that is also effective to protect the damping elements from harm by wake-induced and other high energy oscillations. This latter function is acomplished by integral metal wall structures of the hub that act as stop means when conductor motion beomes excessive. However, under conditions where excessive motion of conductors is prolonged, the metal walls of the hub can become damaged due to prolonged, continuous impacting of the wall structures. Under such conditions, it would be better to have a stop mechanism that does not involve impacting of metal structures.
A damping spacer having motion limiting stop means introduces a shock into the system of the conductor bundle when the bundle experiences the phenomena of wake-induced oscillation. When a shock is applied to a distributed system, such as a conductor bundle, waves occur in the manner of the waves that radiate from the location where a stone thrown into a pond strikes the surface of the pond. The wavelengths and frequencies of these waves are not directly related to the frequency of the wake-induced oscillation, or the frequency at which stones are thrown into a pond. Generally, the frequencies of impact waves in a conductor bundle are higher than the frequency of the wake-induced oscillation. The source of the energy of the impact waves, i.e., the wind, is the same as that causing the conductor to oscillate. Hence, the energy imparted to impact waves is diverted from the energy of the oscillations induced by the wind. For this reason impacts provided by damping spacers appear as a form of damping. In addition, the impact waves that are generated, since they are of a higher frequency than wake-induced oscillations, will generally not correspond to a mode of conductor oscillation that is unstable, i.e., to a mode that tends to oscillate. Rather, the impact waves disperse through the bundle system and die out. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of Invention
The present invention relates generally to optical imaging systems that monitor oxygen levels in tissue. More specifically, the present invention relates to monitoring oxygen levels to determine the viability of flaps before and after a flap transplant.
2. Description of the Related Art
Flap surgery is a type of plastic or reconstructive procedure that enables tissue from one area of a body to effectively be moved to another area of the body. A flap is a section of living tissue with a blood supply that may be transported from a “donor” area of a body to a new area of the body, i.e., an area onto which the flap is to be transplanted. A flap may be transplanted to an area of the body that has lost, for example, skin, fat, or muscle. Flap surgery generally restores some muscle movement or skeletal support to an area in which muscle movement or skin coverage may have been missing.
There are many different kinds of flaps that are used in flap surgery. A local flap is typically a piece of skin with underlying tissue that is located next to a wound. The local flap is repositioned over the wound while remaining attached at one end such that the local flap may be nourished by its original blood supply. A regional flap is generally a section of tissue that is attached by a specific blood vessel or specific blood vessels. When lifted, the regional flap uses a relatively narrow attachment to the donor, or original, site to receive a blood supply from the specific blood vessel or vessels, e.g., a tethered artery and vein. A musculocutaneous flap, i.e., a muscle and skin flap, is typically used when an area to be covered by the flap is relatively large and requires a significant blood supply. A musculocutaneous flap is often used in breast reconstruction surgery, and remains tethered to its original blood supply. A microvascular free flap is a flap of tissue and skin that is detached, along with blood vessels, from an original site of a body and reattached to a new site in the body. As a microvascular free flap is completely detached from an original site, the attachment of such a flap to a new site requires reattaching severed blood vessels at the new site.
Blood flow through transplanted flaps may change drastically in the period of time substantially immediately after a transplant is completed. A transplanted flap may sometimes die, i.e., transplanted tissue may die, when the blood flow through the transplanted flap is compromised. For example, a blood clot in the transplanted flap or a pinched vein in the transplanted flap may cause the transplanted flap to die. Currently, to monitor a transplanted flap to determine whether blood flow through a transplanted flap is adequate to sustain the transplanted flap, laser Doppler flap monitoring may be used. Laser Doppler flap monitoring, or laser Doppler flowmetry, allows Doppler measurements to be made near blood vessels of the transplanted flap. Interpretation of the Doppler measurements may enable potential flap failures to be detected before clinical signs of failure, e.g., discoloration of the transplanted flaps, manifest themselves.
Though laser Doppler flap monitoring may be effective for enabling potential flap failures to be detected in some instances, laser Doppler systems are generally able to make measurements on relatively large vessels, and are unable to measure regional perfusion in the micro-vasculature within a skin flap. Even though flow may be detected in larger vessels when laser Doppler flap monitoring is employed, distal flap tissue may be underperfused and, as a result, may die.
As an alternative to laser Doppler flap monitoring, some surgeons may nick a transplanted flap in various places to assess the blood flow therethrough. Nicking a transplanted flap is invasive and does not always allow for an accurate determination of the viability of a transplanted flap, as assessing the blood flow in such a manner is highly subjective. Further, it may be very difficult to determine where in a transplanted flap to make a nick, e.g., a surgeon may inadvertently fail to make a nick near a blood vessel that is pinched.
Therefore, what is needed is a method and an apparatus which allows the viability of a transplanted flap to be accurately determined. That is, what is desired is a system which is non-invasive and relatively non-subjective, and allows the blood flow through a flap to be accurately assessed. | {
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Botanical classification/cultivar designation: Alstroemeria hybrida cultivar Zalsasweet.
The present Invention relates to a new and distinct cultivar of Alstroemeria plant, botanically known as Alstroemeria hybrida, commercially used as a cut flower Alstroemeria, and hereinafter referred to by the name xe2x80x98Zalsasweetxe2x80x99.
The new Alstroemeria is a product of a planned breeding program conducted by the Inventor in Hillegom, The Netherlands. The objective of the breeding program was to develop new cut flower Alstroemeria cultivars with desirable flower and plant qualities, attractive flower colors and excellent postproduction longevity.
The new Alstroemeria originated from a cross-pollination made by the Inventor in June, 1997 in Hillegom, The Netherlands, of a proprietary Alstroemeria hybrida selection identified as 95705-5, not patented, as the female, or seed, parent with a proprietary Alstroemeria hybrida selection identified as 96391-4, not patented, as the male, or pollen, parent. The new Alstroemeria was discovered and selected by the Inventor as a flowering plant within the progeny of the stated cross-pollination in a controlled environment in Hillegom, The Netherlands in May, 1998.
Asexual reproduction of the new cultivar by root divisions taken in a controlled environment in Hillegom, The Netherlands, since September, 1998, has shown that the unique features of this new Alstroemeria are stable and reproduced true to type in successive generations of asexual propagation.
Plants of the cultivar Zalsasweet have not been observed under all possible environmental conditions. The phenotype may vary somewhat with variations in environment such as temperature and light intensity without, however, any variance in genotype.
The following traits have been repeatedly observed and are determined to be the unique characteristics of xe2x80x98Zalsasweetxe2x80x99. These characteristics in combination distinguish xe2x80x98Zalsasweetxe2x80x99 as a new and distinct cultivar:
1. Erect and strong flowering stems.
2. Vigorous growth habit.
3. Pink and yellow bi-colored flowers with few to no stripes.
4. Good postproduction longevity.
Plants of the new Alstroemeria can be compared to plants of the female parent selection. In side-by-side comparisons conducted in Rijnsburg, The Netherlands, plants of the new Alstroemeria differed from plants of the female parent selection in the following characteristics:
1. Plants of the new Alstroemeria had longer flowering stems than plants of the female parent selection.
2. Plants of the new Alstroemeria and the female parent selection differed in flower color.
Plants of the new Alstroemeria can be compared to plants of the male parent selection. In side-by-side comparisons conducted in Rijnsburg, The Netherlands, plants of the new Alstroemeria differed from plants of the male parent selection in the following characteristics:
1. Plants of the new Alstroemeria had shorter flowering stems than plants of the male parent selection.
2. Inner perianths of plants of the new Alstroemeria were virtually without stripes, however inner perianths of plants of the male parent selection had numerous stripes.
Plants of the new Alstroemeria can be compared to plants of the cultivar Stabec, disclosed in U.S. Plant Pat. No. 9,041. In side-by-side comparisons conducted in Rijsenhout, The Netherlands, plants of the new Alstroemeria differed from plants of the cultivar Stabec in the following characteristics:
1. Plants of the new Alstroemeria had smaller flowers than plants of the cultivar Stabec.
2. Plants of the new Alstroemeria had pink and yellow bi-colored flowers that were virtually without stripes whereas plants of the cultivar Stabec had red and white bi-colored flowers with stripes.
3. Plants of the new Alstroemeria had shorter peduncles than plants of the cultivar Stabec. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a wire with corrosion-resistant terminal.
2. Description of the Related Art
In recent years, aluminum wires have been used for the purpose of weight reduction and the like also in the fields of automotive wiring harnesses and the like. In electrically conductively connecting an aluminum wire to a terminal, electrolytic corrosion in which metals are dissolved in the form of ions in moisture and the corrosion of base metals proceeds by an electrochemical reaction is known to occur if a core of the aluminum wire and the terminal are formed of different types of metals, particularly if moisture is present on a contact part of the both. Here, since the terminal is formed by press-working a copper base material, the electrolytic corrosion of the aluminum wire becomes problematic between copper and aluminum if the aluminum wire is used as a wire as described above.
Accordingly, in a wire with terminal described in Japanese Unexamined Patent Publication No. 2003-297447, electrolytic corrosion is prevented by applying an anticorrosion treatment to a wire connecting portion with a resin mold or the like. However, since this anticorrosion treatment method is for covering the entire wire connecting portion, the wire connecting portion becomes one size larger. Thus, a housing is provided with an escaping structure in some cases in order to avoid the interference of the anticorrosive with the housing in which this terminal is accommodated.
Generally, plating is applied to a surface of a copper base material constituting a terminal. However, in a terminal production process, the copper base material having the surface covered with the plating is punched, whereby copper is exposed on end parts of the base material. Thus, electrolytic corrosion more easily occurs on the end parts of the base material where copper is exposed than on parts having the surface covered with the plating. Specifically, in the case of taking an anticorrosion measure for an aluminum wire with priority given to easy occurrence of electrolytic corrosion, it is first essential to seal the end parts of the base material where copper is exposed with an anticorrosive.
The present invention was completed based on the above situation and aims to realize the miniaturization of a wire with corrosion-resistant terminal by making a range covered with an anticorrosive smaller. | {
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The spine includes a series of joints routinely called motion segment units, which is the smallest component of the spine that exhibits kinematic behavior characteristic of the entire spine. The motion segment unit is capable of flexion, extension, lateral bending and translation. The components of each motion segment unit include two adjacent vertebrae and their apophyseal joints, the intervertebral disc, and the connecting ligamentous tissue. Each component of the motion segment unit contributes to the mechanical stability of the joint.
Components of a motion segment that move out of position or become damaged can lead to serious pain and may lead to further injury to other components of the spine. Depending upon the severity of the structural changes that occur, treatment may include fusion, discectomy, or laminectomy.
Underlying causes of structural changes in the motion segment unit leading to instability include trauma, degeneration, aging, disease, surgery, and the like. Thus, rigid stabilization of one or more motion segment units may be an important element of a surgical procedure in certain cases (e.g., injuries, deformities, tumors, etc.), whereas it is a complementary element in others (e.g., fusion performed due to degeneration). The purpose of rigid stabilization is the immobilization of a motion segment unit Rigid stabilization typically results in a rigid, internal fixation of all or part of intervertebral joints and usually involves metallic rods, screws, plates, and the like for stabilization. In general, the devices are intended to immobilize the motion segment.
In addition to a loss of mobility, total immobilization of the motion segment also can cause unloading of the disk. This can undesirably impact fusion, for example, slowing or even reducing the growth of bone into our through an implant placed into the disc space. Additionally, unloading of the disc can lead to further degeneration of the disk in the immobilized motion segment. Another drawback is that total immobilization also can cause the mobility of the motion segment to be transferred to other motion segments of the spine. The added stresses transferred to motion segments neighboring or nearby the immobilized segment can cause or accelerate the degeneration of those segments.
Thus, there is a need for improved systems that can stabilize motion segments with reduced degeneration of neighboring joints with faster and more substantial fusion. | {
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In general, ceramic capacitors are produced according to the process mentioned below.
First, a plurality of sheet-like dielectric materials each of which is coated with an electrode material to be an inner electrode are prepared. As the dielectric material, for example, employable is a material consisting essentially of BaTiO.sub.3. Next, these sheet-like dielectric materials each coated with such an electrode material are laminated together, pressed under heat to make them integrate, and thereafter fired at from 1250.degree. to 1350.degree. C. in air to give a dielectric ceramic having therein inner electrodes. Next, outer electrodes are attached to the terminals of the dielectric ceramic and electrically connected to the inner electrodes by baking. As a result of this process, a monolithic ceramic capacitor is obtained.
Therefore, the material of such inner electrodes must satisfy the following conditions.
(a) Since the inner electrodes are fired along with the dielectric material, they must have a melting point higher than the temperature at which the dielectric material is fired and PA1 (b) The material of the inner electrodes cannot be oxidized even in an oxidizing, high-temperature atmosphere and cannot react with the dielectric material.
As electrodes that satisfy the above-mentioned conditions, there have heretofore been employed noble metals such as platinum, gold, palladium, silver-palladium alloys, etc.
However, these electrode materials are expensive, although they have excellent characteristics. As a result, the proportion of the cost of electrode materials to the total cost in producing monolithic ceramic capacitors reached from 30 to 70%, and, therefore, was the most essential factor in increasing the production costs of such monolithic ceramic capacitors.
Apart from such noble metals, base metals such as Ni, Fe, Co, W, Mo, etc. are known to have a high melting point. However, these base metals are easily oxidized in an oxidizing atmosphere at high temperatures and therefore cannot be used as electrodes in such monolithic ceramic capacitors. Therefore, if these base metals are desired to be used as inner electrodes in monolithic ceramic capacitors, they must be fired in a neutral or reducing atmosphere along with the dielectric material. However, if conventional dielectric materials are fired in such a neutral or reducing atmosphere, they are noticeably reduced and converted into semiconductors.
In order to solve this problem, for example, a dielectric material comprising a solid solution of barium titanate where the ratio of barium sites/titanium sites is more than the stoichiometric ratio, such as that disclosed in Japanese Patent Publication No. 57-42588, and a dielectric material comprising a solid solution of barium titanate with an oxide of a rare earth metal such as La, Nd, Sm, Dy, Y or the like added thereto, such as that disclosed in Japanese Patent Laid-Open No. 61-101459, have been proposed.
In addition, other dielectric materials modified to have a reduced temperature-dependent variation in the dielectric constant have been proposed. As examples, mentioned are the composition of BaTiO.sub.3 --CaZrO.sub.3 --MnO-MgO such as that disclosed in Japanese Patent Laid-Open No. 62-256422 and the composition of BaTiO.sub.3 --(Mg, Zn, Sr, Ca)O-B.sub.2 O.sub.3 --SiO.sub.2 such as that disclosed in Japanese Patent Publication No. 61-14611.
By using these dielectric materials, it has become possible to obtain dielectric ceramics that are not converted into semiconductors even when fired in a reducing atmosphere, and the production of monolithic ceramic capacitors having inner electrodes made of base metal such as nickel and the like has been realized.
With recent developments in electronics, small-sized electronic parts have become much more popular, and the tendency toward small-sized, large-capacity monolithic ceramic capacitors has become remarkable.
Given the situation, the development of dielectric materials having an enlarged dielectric constant and also thin dielectric layers is desired. Accordingly, there is a great demand for reliable dielectric materials having a high dielectric constant and having a temperature-dependent variation in the dielectric constant.
However, the dielectric ceramics to be produced from the dielectric materials as disclosed in Japanese Patent Publication No. 57-42588 and Japanese Patent Laid-Open No. 61-101459 comprises large crystal grains, even though the materials have a high dielectric constant. Therefore, if the dielectric ceramics are used to produce thin dielectric layers having a thickness of not larger than 10 .mu.m in monolithic ceramic capacitors, the number of the crystal grains in each dielectric layer is decreased with the result that it is difficult to improve the quality and the reliability of the monolithic ceramic capacitors comprising the layers. In addition, the temperature-dependent variation in the dielectric constant of the dielectric materials is large.
On the other hand, the dielectric material as disclosed in Japanese Patent Laid-Open No. 62-256422 has a relatively high dielectric constant, and the dielectric ceramic to be produced from the material comprises small crystal grains and has a small temperature-dependent variation in the dielectric constant. In the material, however, CaZr.sub.12 O.sub.3 and also CaTiO.sub.3 that are formed during baking easily give a secondary phase along with Mn and others. Therefore, it is difficult to improve the reliability of the material at high temperatures.
The dielectric material as disclosed in Japanese Patent Publication No. 61-14611 has a dielectric constant of from 2000 to 2800. Therefore, it is difficult to say that the material is suitable in producing small-sized, large-capacity monolithic ceramic capacitors. In addition, the material does not satisfy the requirement stipulated in EIA Standard, which is such that the variation in the electrostatic capacity of condensers at temperatures falling between -55.degree. C. and +125.degree. C. shall be within .+-.15%.
In order to make them applicable to automatic surface mounting, small-sized, large-capacity monolithic ceramic capacitors have a plated film of solder or the like over the outer electrodes formed by baking an electroconductive metal powder. Electrolytic plating is generally employed to form such a plated film.
In general, the electrodes to be formed by baking an electroconductive metal powder have fine voids. Therefore, if a monolithic ceramic capacitor with such outer electrodes is dipped in a plating bath so as to form a plated film on the electrodes, the plating liquid penetrates into the electrodes through their voids. As the case may be, the plating liquid often reaches the interface between the inner electrode and the dielectric ceramic layer. For these reasons, the dielectric materials mentioned above are problematic in that their reliability is lowered. | {
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A number of instruments exist for mapping optical elements, and especially for ophthalmic use. Such instruments generally use a Hartman Shack matrix for analyzing the refractions of a beam of light transmitted through the spectacle lens. In U.S. Pat. No. 5,825,476, there is described such a system, and other such systems are cited in that patent. One of the major disadvantages of many of such prior art instruments is that the user places the spectacle frames directly on the measurement table, such that the reference plane used to align the lenses is then effectively that of the frame itself, and not of the lenses being mapped. Consequently, if the lens form has a large element of sag, or if the lens has a large tilt, then the mapping results obtained may be inaccurate. Furthermore, in many such prior art instruments, the frames have to be aligned manually or by means of motors in order to align the mechanical center of the lenses being measured with the measurement beam.
There therefore exists a need for a spectacle measurement system, which can map both lenses automatically and which overcomes at least some of the disadvantages of prior art systems and methods.
The disclosures of each of the publications mentioned in this section and in other sections of the specification, are hereby incorporated by reference, each in its entirety. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a semiconductor device and a manufacturing method therefor.
2. Description of the Related Art
The demands for reduction in chip area with respect to memory LSI, system LSI, and other semiconductor devices, are increasing each year, coupled with the miniaturization of information communications equipment in recent years. It is desired, therefore, that memory cell areas be reduced with the conventional electrical characteristics of transistors being maintained. Vertical transistors are employed as an approach to implementing such reduction in cell area. Conventional vertical transistors include: a type in which, as disclosed in Japanese Patent Laid-open No. 2001-320031, a hole is formed in the thin film formed on a silicon substrate and a vertical transistor has its channel embedded in the hole; a type in which, as disclosed in Japanese Patent Laid-open No. 10-107286, a hole is formed in a silicon substrate and a side of the hole is used as a channel; and a type in which, as disclosed in Japanese Patent Laid-open No. 10-326879, a protrusion of silicon is formed on a silicon substrate and used as a channel.
The conventional vertical transistors require preventive measures against the deterioration of their electrical characteristics, increases in the nonuniformity of the characteristics, and other events. In embodiments of the aforementioned conventional technologies, however, concrete preventive measures are not incorporated against decreases in product yield or against performance deterioration. The present inventors have studied the fact that the deterioration of electrical characteristics and increases in the nonuniformity thereof, caused by excessive stresses in comparison with those of conventional lateral transistors, result in product yield decreases and performance deterioration becoming problems. That is to say, the present inventors have studied the fact that the above is associated with several problems. More specifically, since the region for forming a channel is excessively stressed, drain current “ids” is affected by the stress. Also, since the stress on a gate oxide film also becomes excessive similarly, the leakage current in the gate oxide film increases. In addition, nonuniform processing of the silicon section including the channel region easily changes the internal stress thereof and the stress on the gate oxide film, thus increasing not only drain current “ids”, but also the leakage current in the gate oxide film and the nonuniformity of withstand voltage characteristics. | {
"pile_set_name": "USPTO Backgrounds"
} |
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