A method of manufacturing a thin film transistor array panel is provided, which includes: forming a gate line on a substrate; depositing a gate insulating layer and a semiconductor layer in sequence on the gate line; depositing a lower conductive film and an upper conductive film on the semiconductor layer; photo-etching the upper conductive film, the lower conductive film, and the semiconductor layer; depositing a passivation layer; photo-etching the passivation layer to expose first and second portions of the upper conductive film; removing the first and the second portions of the upper conductive film to expose first and second portions of the lower conductive film; forming a pixel electrode and a pair of redundant electrodes on the first and the second portions of the lower conductive film, respectively, the redundant electrodes exposing a part of the second portion of the lower conductive film; removing the exposed part of the second portion of the lower conductive film to expose a portion of the semiconductor layer; and forming a columnar spacer on the exposed portion of the semiconductor layer.

(a) Field of the Invention
The present invention relates to a thin film transistor array panel and a manufacturing method thereof.
(b) Description of the Related Art
A liquid crystal display (LCD) is one of the most widely used flat panel displays since it is lightweight and occupies less space than conventional cathode ray tube (CRT) displays. An LCD generally includes a liquid crystal (LC) layer that is interposed between a pair of panels including field-generating electrodes such as pixel electrodes and a common electrode. The LC layer is subjected to an electric field generated by the field-generating electrodes and variations in the field strength change the molecular orientation of the LC layer. For example, upon application of an electric field, the molecules of the LC layer change their orientation to change polarization of incident light. Appropriately arranged polarizers partially or fully block the light, creating gray or dark areas that can represent desired images.
One panel for the LCD generally includes a plurality of pixel electrodes, a plurality of thin film transistors (TFTs) for controlling signals to be applied to the pixel electrodes, a plurality of gate lines transmitting control signals for controlling the TFTs, and a plurality of data lines transmitting data voltages to be supplied to the pixel electrodes. The other panel generally includes a common electrode disposed on an entire surface thereof.
The TFT array panel including the TFTs includes several conductive films and insulting films. The gate lines, the data lines, and the pixel electrodes are formed of different films and they are separated by insulating films and sequentially arranged from bottom to top.
The TFT array panel is manufactured by several steps of film deposition and photolithography steps. Accordingly, it is important to obtain stable elements using a minimum process steps.

Thin film transistor array panel and manufacturing method thereof


A method for manufacturing a light-emitting diode (LED) is described. The method comprises: providing a temporary substrate; forming an illuminant epitaxial structure on the temporary substrate; forming a first transparent conductive layer on the illuminant epitaxial structure; forming a metal substrate on the first transparent conductive layer; forming an adhesion layer on the metal substrate; providing a supporting substrate, wherein the supporting substrate is connected to the metal substrate by the adhesion layer; removing the temporary substrate, so as to expose a surface of the illuminant epitaxial structure; forming a second transparent conductive layer on the exposed surface of the illuminant epitaxial structure; and forming an electrode on a portion of the second transparent conductive layer.

Light-emitting diodes are semiconductor illumination devices formed by using semiconductor materials. The light-emitting diodes are one kind of minute solid-state light source that can transform electrical energy into light energy. The semiconductor have many advantages, including small volume, a low driving voltage, rapid response speed, resistance to shock, and long life, and also can meet the light, thin, and miniaturization needs of various apparatuses. Light-emitting diodes have thus have become very popular electric products in daily life.
In the fabrication of light-emitting diodes, III-nitride-based semiconductors, such as GaN, AlGaN, InGaN and AlInGaN, are common. Usually, epitaxial structures of most of the light-emitting devices made of the III-nitride-based semiconductors are grown on an electrically insulating sapphire substrate, which is different from other light-emitting devices utilizing conductive substrates. The sapphire substrate is an insulator, so an electrode can be directly formed on the sapphire substrate. Electrodes have to be formed to contact respectively a p-type semiconductor layer and an n-type semiconductor layer directly, so that the light-emitting devices of the aforementioned type can be completed.
FIG. 1 illustrates a cross-sectional view of a conventional light-emitting diode. In the fabrication of the light-emitting diode, a buffer layer 102 is firstly formed on a transparent substrate 100 by deposition. The substrate 100 is typically made of sapphire. An n-type semiconductor layer 104 is epitaxially formed on the buffer layer 102, in which the n-type semiconductor layer 104 is typically made of III-nitrides. Next, an active layer 106 is epitaxially formed on the n-type semiconductor layer 104, in which the active layer 106 is typically a multiple quantum well (MQW) structure. A p-type semiconductor layer 108 is epitaxially grown on the active layer 106, in which the p-type semiconductor layer 108 is typically made of III-nitrides. An illuminant epitaxial structure is composed of the n-type semiconductor layer 104, the active layer 106 and the p-type semiconductor layer 108.
The substrate 100 is made of sapphire, an insulator, so contact electrodes of the light-emitting diode have to be formed to contact respectively the p-type semiconductor layer 108 and the n-type semiconductor layer 104 directly, and cannot be directly formed on the substrate 100 made of sapphire. Accordingly, after the illuminant epitaxial structure is formed, a definition step is performed by photolithography and etching to remove a portion of the active layer 106, a portion of the p-type semiconductor layer 108 and a portion of the n-type semiconductor layer 104, so as to expose a portion of the n-type semiconductor layer 104. Then, an electrode 110 and an electrode 112 are respectively formed on the p-type semiconductor layer 108 and the exposed portion of the n-type semiconductor layer 104 is formed directly by thermal evaporation, E-beam evaporation or ion-sputtering, so that the fabrication of the light-emitting diode is completed.

Method for manufacturing light-emitting diode


By using embodiments of the present invention, a targeted advertisement, or other customized content, can be published to a consumer when visiting a website. The consumer is connected to a mobile broadband network and is authenticated and authorized to this broadband network. Further, the consumer is given an Internet Protocol (IP) address of the mobile broadband network and this IP address is used to identify the consumer when the targeted advertisement is determined according to a profile of the consumer.

Internet advertising has been present for a long time creating a vast market of advertising solutions. The Internet advertising is very mature and with help of search services, search based advertising is introduced. By using keywords and contextual information of the visited websites the ad networks get a hint of the consumers' profile this enables the ad networks to provide more relevant advertisements for a consumer that is surfing a specific website.
Another ordinary, well used, technique is to store information about the consumer in the browser cookie files. The cookie stores browsing data for a web site.
The advertisers and the media agencies that help the brands to reach out with their message has an interest to always reach the most suitable and desirable consumer category. The more information about the consumer the better relevance the brands will get with their advertising activities. To be seen in the right place for the right consumer is the main target for the advertisers.
Today internet traffic in mobile broadband networks is increasing fast. The internet traffic can be analyzed to derive information about subscriber's internet behavior and dynamic subscriber profiles can be created. A challenge for the mobile broadband (MBB) networks operators is to efficiently analyze all this internet traffic information and leverage on the analysis results.
An example of how the analysis results can be used is transmission of advertisements and other customized content exemplified by mobile apps, games, ring tones, movies, music, etc. This is a growing area and has a huge potential to enable advertisers and content providers to provide customized content and advertisements to the consumers. In order to optimize the revenue for the advertisers and content providers, it is important to optimize the distribution of the content by sending each content to the consumers that have consumer profiles that best fit the type of the content. This is referred to as targeted advertising or targeted content.
Today Mobile Broadband (MBB) subscriber identity over internet and especially mobile broadband is not utilized for targeted advertising. However, every MBB subscriber is connected to the MBB and identified by a Mobile Subscriber Integrated Services Digital Network Number (MSISDN) or similar subscriber identity. Further, each MBB subscriber is allocated an IP address. How to bind the IP address of a MBB subscriber to a specific MSISDN is known technology.
Collecting consumer profile data and storing these profiles with the MSISDN as key for a specific consumer is also known technology.
The MBB devices that can be used are normally Netbook, Laptop or Desktop, but it can also be tablets and smartphones etc. that can surf on the web or install an application.
Nevertheless, still today there exists no solution to utilize the consumer profile information such as the consumer demographics as gender and age, behavioral as e.g. high spender and influential for advertising on the Internet.
Consumer information can be detailed and precise or abstracted in consumer segments and it comes from various sources such as analytic/data mining systems, location based systems, and Call Data Records collected from telecom nodes.
The solution on how to recognize the consumer profile on the public Internet and to make it available for purchase and usage towards the advertising industry/market is still an untapped area.

Method and network node for distributing customized content

Abstract: This is achieved according to embodiments by letting the publisher request a targeted advertisement for a consumer visiting a website of the publisher. The targeted advertisement is found by using the IP address allocated to the consumer device by the mobile broadband network, i.e. the consumer is identifiable by the IP address. By using the mobile broadband operator's ability to map the IP address and the consumer identity a consumer profile of the consumer is found and based on the consumer profile the targeted advertisement can be determined and shown to the consumer. The consumer profile is controlled by the mobile broadband network.


A symmetric relay system for endoscopes includes an optically-aligned pair of elongated concavo-convex rod-type lenses formed from crown glass, to the convex end surface of each of which a meniscus-shaped flint lens is cemented. The concave ends of the rod lenses are disposed to face the intermediate images of the relay system, and the convex ends to face the aperture of the relay system. A pair of achromatic lenses, each formed of a pair of lens elements x, y, are disposed adjacent and in optical alignment with the respective concave ends of the rod lenses between the concave rod ends and the intermediate images. Each achromatic lens fulfills the condition n x/ny=vx/vy. Apochromatic glass combinations may be used in the rod lenses to significantly reduce the secondary spectrum.

1. Field of the Invention
The present invention relates to optical lens systems and, more particularly, to relay lens systems especially suitable for use in medical endoscopes and other optical imaging devices.
2. Description of Related Art
Medical endoscopes are used to view internal body organs through small openings created in and through the body wall or skin or by way of existing openings or orifices. Such instruments typically include a long, thin, rigid or semi-rigid optical cylinder that is mounted on or to a viewing mechanism or imager. When the endoscope is inserted and positioned for use, an image of the object being viewed is formed by an objective lens at the inserted or distal end of the endoscope. The image passes through a series of relay lenses along the cylinder to a viewer comprising an eyepiece or viewing lens or a video camera or imager at the viewing or proximal end of the endoscope.
The relay lenses must be very narrow and are typically in the range of about 2.4 mm to 6.0 mm in diameter and approximately 20 mm to 50 mm long. Each relay lens is commonly formed of two or more elements, and a pair of relay lenses make up a set of such lenses. Most endoscopes require two or more sets of relay lens pairs for proper operation. The number of sets generally depends on the length and specific requirements of the particular endoscope and/or the application for which it is intended.
Optimization of endoscope performance involves the adjustment, in the design and implementation of the endoscope, of many factors including brightness, contrast, resolution and corrections for various aberrations. Of particular significance are compensations for minimizing the basic Seidel aberrations (spherical aberration, coma, astigmatism, field curvature, distortion and axial and transversal chromatic aberration) as well as secondary spectrum and higher order aberrations. Typically, meaningful correction of one or more of these factors results in a concomitant loss of performance in one or more of the remaining factors.
Brightness of the image that is transmitted through a relay lens system is related to the ratio of the focal length and the diameter of the lens through which the image is being focused, a ratio commonly denoted the f-number. The smaller the f-number, the brighter the image transmitted by the lens. It is preferable in an endoscopic relay lens system to have a system f-number that is as small as possible so that maximum brightness is transmitted from the objective lens to the eyepiece. The resulting image brightness is also impacted by both absorption of energy by the lens media and unwanted reflection losses at interfaces of the lens elements.
Optical systems for medical endoscopes using relay lenses have been known since as early as 1879. In about 1908 a physicist from Zeiss, Moritz Rohr, developed improved optical systems for endoscopes using two or more relay systems. The introduction of anti-reflection coatings for optical components after the end of the Second World War allowed for the use of 3 or more relay systems in an endoscope.
In about 1959, H. H. Hopkins received a patent for a symmetric rod lens system. This relay system technology, and derivatives thereof, became the state of the art for most optical endoscope systems during the 1980""s and 1990""s. Although the Hopkins rod lens relay system corrects axial aberrations, it does not correct field curvature and astigmatism. Optical systems with that relay system necessarily require corrective elements in the objective system with extreme curvatures which are needed to compensate for the accumulated aberrations of the device""s multiple relay systems. The disadvantage of such systems is that for relay lenses with higher numerical apertures, the higher order aberrations of the objective system are unable to fully compensate for the higher order aberrations that are accumulated in the multiple relay systems of the device.
In the 1980""s and 1990""s efforts were made to develop relay systems for disposable endoscopes. See, for example, U.S. Pat. No. 4,946,267 to Hoogland, U.S. Pat. No. 4,784,118 to Fantone et al., and U.S. Pat. No. 5,188,092 to White. These relay systems use pressed aspheres formed of plastic material. Glass rods with plane surfaces may also be added to increase the numerical aperture. However, these relay lens systems do not attain the image quality achieved by systems using only glass lenses, and neither do they meet the performance expectations of surgeons. In addition, the costs per use tend to be higher, overall, than for endoscopes using non-disposable relay systems.
U.S. Pat. No. 5,059,009 to McKinley discloses an endoscope relay lens system containing a symmetric pair of rod lenses in which long flint glass rod lenses are cemented on opposite sides of a biconvex crown glass rod that is formed from a glass ball. This relay lens system, which forms an imaging system, corrects the off-axial aberrations better than relay lens systems based on the Hopkins patent, although the correction is not complete. Specifically, the meridional image curvature is overcorrected, so that the meridional and sagittal image curvatures bend with the same curvature on both sides of the Gaussian image plane but with different signs. As a result, astigmatism remains in this system. Furthermore, the meridional and sagittal image curvatures bend further away from one another as more relay systems are added. Thus, even if the Petzval sum is corrected using strong curvatures in the objective system, the over-corrected astigmatism of this relay system can only be compensated by an under-correction of astigmatism in the objective system. The consequence is a detrimental effect on correction of the coma.
The shortcomings of the McKinley lens system were partially addressed in U.S. Pat. No. 5,568,312 to Horton, in which the relay lens system comprises three axially aligned cylindrical lens pairs, with each lens pair having two substantially rod-like lenses. The system uses three different materialsxe2x80x94namely glass, cement and a polymerxe2x80x94as well as air interfaces to provide improved correction of chromatic and geometric aberrations. The effective f-number of each relay lens element is minimized, as is the number of lens element interfaces, to provide a brighter image. Problems, however, nevertheless remain in this system.
Relay systems currently available need to have both the axial aberration and off-axial aberrations corrected. The objective systems necessary to transfer the viewed object image to the entrance of the relay system and the eyepiece needed to transform the intermediate image from the end of the relay system to the image plane of the endoscope are only able to minimize the aberrations of their associated subsystem, and do not compensate for image aberrations that are accumulated in the relay system as a whole.
In addition, relay lenses for stereo endoscopes require a much higher numerical aperture than do relay lenses for mono endoscopes. Each of the two entrance pupils of a stereo endoscope must be as large as the single entrance pupil of a mono endoscope. But increasing the brightness of current stereo relay lens systems results in an unsatisfactory image. Currently available endoscope relay systems, when used in stereo applications, do not perform as well as mono endoscopes with such relay systems. Surgeons are therefore left in a disadvantaged position as the superior images produced in mono systems lack the apparent depth that can only be achieved with a stereo system.
There is currently a widespread and unsatisfied demand for better mono and stereo endoscopes. Surgeons using these instruments require that the image produced be both clear and sufficiently large and bright, with high resolution and low distortion. It is also desirable for there to be an appreciable three-dimensional or depth perception aspect to the image which requires a stereo relay system rather than a mono system. Finally, resolution in currently available endoscopic optical relay systems is rapidly becoming a limiting factor in the quality of the perceived image. New viewing technology such as HDTV camera sensors and imaging arrays, which allow for greater image resolution than heretofore available CCD (charge-coupled device) video chips, are becoming available for use in conjunction with endoscopes. This technology is driving a demand for endoscopes of increased image brightness, for endoscopes with higher magnification but the same resolution, and for endoscopes with higher resolutions than existing endoscopes. This strong demand for endoscopes with better overall performance can only be satisfied using relay systems of higher numerical aperture and better, or at least equivalent, correction of image aberrations than existing relay systems.
It is accordingly the desideratum of the present invention to provide a symmetric anastigmatic relay system for endoscopes which includes a relay lens system that corrects off-axial aberrations while exhibiting a higher numerical aperture than existing lens systems.
A symmetric anastigmatic relay system constructed in accordance with the present invention has a longitudinally and optically-aligned pair of meniscus (i.e. concavo-convex) shaped, elongated rod-type lenses formed of crown glass, a pair of meniscus-shaped flint lenses cemented on the convex end surfaces of the rod lenses, and a pair of two-element achromatic lenses positioned adjacent to the opposite-end concave end surfaces of the rod lenses. The achromatic lenses of the inventive arrangement satisfy the condition for xe2x80x9cnew achromats,xe2x80x9d namely nx/ny=vx/vy, where n is the refraction index and v is the Abbe number of the lens elements x and y that together form each achromatic lens. The achromatic lenses are mounted adjacent or in close proximity to the concave end faces of the rod lenses between the concave end faces and the intermediate images of the relay system so that they face, or confrontingly oppose, the intermediate images. The flint lenses cemented on the convex end faces of the rod lenses face the aperture of the relay system. The concave surfaces of the rod lenses, in conjunction with the achromatic lenses, reduce the field curvature of the relay system to zero. The cemented surfaces of the rod lenses and the cemented surfaces of the achromatic lenses reduce spherical aberration and astigmatism. Using flint and crown glasses in the rod lenses, in combination with the achromatic lenses, reduces primary chromatic aberrations to a minimum.
In an embodiment of the present invention, apochromatic glass combinations are used in the rod lenses to significantly reduce the secondary spectrum.
In a further embodiment of the invention for relay systems with high numerical aperture, the air surfaces of the flint lenses cemented to the rod lenses are aspheric, thereby providing a further reduction of spherical aberration.
In another embodiment of the invention, a reduction in variations of the correction of aberrations over or across the field of the intermediate images is achieved by making either the air-interfacing surfaces of the negative lens elements or the air-interfacing surfaces of the positive lens elements of the achromatic lenses aspheric.
In yet another embodiment of the invention, for relay systems with both high numerical aperture and large intermediate images, the air surfaces of the flint lenses cemented to the rod lenses and the air surfaces of either the negative lens elements or the positive lens elements of the achromatic lenses are aspheric.
In a still further and most preferred embodiment of the invention, an apochromatic glass combination is used in the rod lenses, aspheric surfaces are used on the air-interfacing surfaces of the flint lenses cemented to the rod lenses, and aspheric surfaces are used on the air-interfacing surfaces of either the negative lens elements or the positive lens elements of the achromatic lenses. Alternatively, instead of providing aspheric surfaces on the air-interfacing surfaces of the flint lenses cemented to the rod lenses, the glass for those flint lenses may be formed or manufactured from an axial gradient material. In another alternative, the glasses for either the negative lens elements or the positive lens elements of the achromatic lenses can be formed from axial gradient material.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.

Symmetric anastigmatic endoscope relay system


This patent discloses a system to release a seatbelt in a vehicle automatically. The system may include a seatbelt sensor, mishap sensors, a controller, and a guillotine unit. The controller may communicate signals with the seatbelt sensor and mishap sensors and the guillotine unit may receive signals from the controller. The guillotine unit may include a webbing guide, a gas chamber having a supply of pressurized gas, and a gas supply line connected between the webbing guide and the gas chamber. The webbing guide may include spring biased piston and a blade attached to the piston at a positioned above a seatbelt webbing of the seatbelt. On receiving a cut signal from the controller, pressurized gas from the gas chamber may be released to cause the piston to move the blade through the seatbelt webbing to slice through seatbelt webbing.

Priority is claimed to South Africa patent application no. 2003/4782 filed in South Africa on Jun. 20, 2003, the entire disclosure of which is incorporated herein by reference.
1. Field
The information disclosed in this patent relates to a system to release a seatbelt in a vehicle automatically.
2. Background Information
A seatbelt, sometimes called a safety belt, may be viewed as a safety harness to secure the occupant of a vehicle against harmful movement that may result from a collision or a sudden stop. As part of an overall occupant restraint system, seatbelts may reduce injuries by stopping the wearer from hitting hard interior elements of the vehicle or other passengers and by preventing the wearer from being thrown from the vehicle.
While seatbelts are beneficial in protecting people from an initial collision, their restraining feature may pose serious problems should the vehicle catch fire, overturn, fall into a lake, or experience some other mishap. Worldwide, thousands of people including infants are trapped in their vehicles due to head on collisions, vehicles over turning, or vehicles catching fire.
Due to the immense force the body exerts onto the seatbelt unlocking mechanism during a collision, the seatbelt unlocking mechanism invariably is twisted in such a way that neither rescuer nor the trapped person can reach the unlocking mechanism. In the panic situation often following a collision, bystanders run around the vehicle searching for something to release the safety belt. It is during this time that accident victims suffer significant harm. What is needed is system to overcome these and other problems.


A switch, such as an electromechanical or optical switch, whose state is responsive to temperature history, for example temperature excursions above or below a critical temperature. An element of the sensor made from shape memory alloy changes shape when exposed, even temporarily, to temperatures above the Austenitic start temperature As or below the Martensite start temperature Ms of the shape memory alloy sensor element. The shape change of the SMA element causes the sensor to change between two readily distinguishable states. The sensor can include a one-way stop element that creates a persistent indication of the temperature history. The switch also has built-in stops allowing the sensor to be manufactured and stored at temperatures above the Austenitic temperature without causing the indication of an over-temperature event, before the actual use.

This invention relates to temperature sensors, specifically shape memory alloy temperature sensors that provide persistent indication once their temperature reaches, exceeds or goes below a critical value.
Exposure to temperatures above or below a critical temperature can damage many important materials. Food products such as frozen dairy products and frozen meats can spoil when exposed to thawing temperatures for even a short time. Products that need to be kept cool but unfrozen, such as pharmaceutical drugs, vaccines, and serums can spoil if frozen temporarily and then warmed up to normal but cool temperatures. Frozen medical products such as blood and certain pharmaceuticals can be unsafe once exposed to thawing or other high temperatures, even if the temperature later returns to a safe value. Low temperatures can also compromise important properties of some rubber and rubber-like materials. The damage is often unseen, and can persist even if the temperature returns to an acceptable level. This situation can arise in transportation, where a frozen product temporarily experiences high temperatures due to improper handling or cooling equipment malfunction or a cooled product temporarily experiences a freezing temperature due to improper handling or cooling equipment malfunction.
Many conventional temperature sensors do not provide a persistent record of temporary temperature deviations. Conventional temperature sensors, such as common thermometers, indicate the current temperature only. They provide a continuous indication of the current temperature of the material. They do not provide a permanent indication of out-of-range temperatures without additional permanent recording apparatus. Accordingly, there is a need for sensors that provide a persistent record of temporary out-of-range temperatures.
Shape memory alloys (SMAs) have properties that can be useful in developing the needed sensors. An SMA can be trained to have a certain shape in its Austenitic state or at temperatures above the SMA's Austenitic finish temperature Af. The SMA moves in a certain fashion to a second shape, its Martensitic state, which is a softer state for the material, when the temperature drops below the Austenitic finish temperature Af and eventually reaches below the Martensite start temperature Ms. The SMA will not return to the Martensite shape without additional external force even if the temperature subsequently falls below the Austenitic temperature Af. SMAs are used in a variety of applications, such as those described in "Design and Modeling of a Novel Fibrous SMA Actuator," Proc. SPIE Smart Materials and Structures Conference, vol. 2190, pp. 730-738 (1994), and "A Phenomenological Description of Thermodynamical Behavior of Shape Memory Alloys," Transactions of the ASME, J. Appl. Mech., vol. 112, pp. 158-163 (1990). SMAs have been suggested for use in persistent temperature indicators. See Shahinpoor, U.S. Pat. No. 5,735,607, incorporated herein by reference. The sensors suggested by the U.S. Pat. No. 5,735,607 patent, however, can require that the apparatus be kept below the threshold temperature during assembly and storage. This requirement can complicate manufacture and handling. There is a need for temperature indicators that can be manufactured, stored, and handled at arbitrary temperatures, then enabled to provide a persistent record of temporary temperature deviations. There is a further need for such indicators that can be integrated with other systems, where the temperature indicator can be used to control, activate, or deactivate other systems according to the state of the temperature indicator.

Shape memory alloy temperature sensor and switch


A memory controller, such as a memory controller for reading data received from a DDR SDRAM memory, may detect the beginning and end of a read cycle. The memory controller may include a preamble detection circuit to receive a strobe signal and output a first control signal indicating detection of a preamble window in the strobe signal that indicates a beginning of the read cycle, where the first control signal is delayed based on a selectable delay period applied to the first control signal. The memory controller may further include a first gate to, based on the first control signal, either output the strobe signal for reading of the data lines or block the strobe signal, and the control logic to set an amount of the selectable delay period for the preamble detection circuit.

Random access memory (RAM) is a type of storage for computing devices. RAM is typically associated with volatile memory that is implemented in integrated circuits and in which stored information is lost when power provided to the RAM is switched off.
One type of RAM is known as DDR SDRAM (double-data-rate synchronous dynamic random access memory). DDR SDRAM is typically used in computing applications that require high bandwidth and low latency memory access. One version of this memory technology is known as DDR3 SDRAM, which can provide for high performance data rates, high bandwidth, high density, and low power consumption relative to earlier generations of SDRAM.
The high bandwidth and high operating frequencies required to drive DDR SDRAM can be problematic as they can make the controller to memory interface electrically complex due to signal integrity considerations. A DDR3 SDRAM controller and associated memory may perform read and write operations synchronously based on a periodic signal transmitted over a "strobe" line. Static and dynamic timing variations between the strobe line and a data line can cause memory errors. Static variations that cause timing skew between the strobe and data lines may be due to, for example, on-die process and wire variations across strobe and data logic, on-chip power supply grid variations, package and board interconnect, and material variations. Dynamic timing variations may be caused by short or long term voltage drift and temperature changes during functional operation of the interface
The strobe line may be used to signal the beginning and end of a burst of data. A read "preamble cycle" may be used to indicate the beginning of a read burst and a "postamble cycle" may be used to signal the end of the read burst. For high frequency memory operation, detection of the read preamble window and appropriate postamble closure at the controller is not trivial as board round trip delays, and static and dynamic timing variations can cause the preamble window to cross one or more clock cycle boundaries.
Existing techniques to detect read preamble and postamble cycles may be based on an echo clock emitted from a memory controller. This technique, however, may require dedicated input/output (I/O) pins and may not be effective when preamble arrival times cross a clock cycle boundary.

Preamble detection and postamble closure for a memory interface controller


An optical recording medium which is a multilayer optical recording medium including a plurality of recording layers and records or reproduces information by the irradiation of light having a wavelength of λ0. At least one recording layer out of a plurality of recording layers includes a variable absorption film. The variable absorption film contains a material in which an electron energy has a band structure, and the absorption end of an absorption spectrum moves toward a longer wavelength side with a rise in temperature when light is absorbed by transition between electron bands, has a first absorptance to light having a wavelength of λ0 when a film temperature is a first temperature (application environment temperature), and has a second absorptance higher than the first absorptance to light having a wavelength of λ0 when a film temperature is a second temperature higher than the first temperature.

In recent years, large-capacity external storage devices are desired as society becomes more and more computerized. In optical recording of information, there is conventionally a limit to higher density achieved by reducing the size of a recording pit because of a diffraction limit defined by the wavelength of light and the numerical aperture of an objective lens. In order to solve the above-mentioned problem, multilayer optical recording media having a plurality of recording layers are proposed (e.g., JP 5(1993)-151591 A). However, in such mutilayer-type optical recording media, a semitransparent film having a certain reflectance and transmittance with respect to light is used for the recording layers, which results in a light loss due to light reflection in recording layers other than a target recording layer. Moreover, with an upstream side in the traveling direction of incident light being the upper side, and a downstream side being the lower side, transmitted light also reaches layers located lower than the target recording layer, resulting in a further light loss.
In order to solve the above-mentioned problems, multilayer optical recording media that use a nonlinear material having nonlinear optical characteristics for recording layers are proposed (e.g., JP 2000-3529 A).
FIG. 11 shows a cross-sectional configuration of a conventional multilayer optical recording medium. The optical recording medium as shown in FIG. 11 includes a first recording layer 12 located between a first light transmission film 10 and a second light transmission film 14, and a second recording layer 16 formed so as to be opposed to the first recording layer 12 with the second light transmission film 14 sandwiched therebetween. Further, the first recording layer 12 is provided with guide grooves 12A. The first recording layer 12 is formed of a nonlinear reflective material having a reflectance that nonlinearly increases with the intensity of light. As the nonlinear reflective material having such properties, a-Si, InSb, ZnTe, ZnSe, CdSSe, GaAs, GaSb, or the like may be used. When the first recording layer 12 is formed of such a nonlinear reflective material, the first recording layer 12 has a reflectance changing in accordance with |(n−ns)/(n+ns)|2. Herein, "ns" represents the refractive index of the light transmission films 10 and 14, and "n" represents the refractive index of the first recording layer 12 as a nonlinear reflective material. The nonlinear reflective material used here is a material that causes a phenomenon in which the refractive index changes depending upon the light intensity, i.e., a material having a great nonlinear optical effect.
The optical characteristics of such an optical recording medium will be described. When the first recording layer 12 is accessed, a light spot is formed on the first recording layer 12, and accordingly the first recording layer 12 is irradiated with a relatively intense light beam. The reflectance of the first recording layer 12 at this time may be 40%, for example. On the other hand, when the second recording layer 16 is accessed, a radiated light spot is formed on the second recording layer 16, and accordingly the first recording layer 12 is irradiated with relatively weak light. The reflectance of the first recording layer 12 at this time may be 30%, for example, which means the first recording layer 12 reflects 30% of incident light and transmits 70% thereof to the second recording layer 16 side. Thus, the second recording layer 16 can be accessed efficiently.
However, the above-described prior art provides only a 10% reflectance change, from 30% to 40%. This is a limit due to the fact that the material having nonlinear optical characteristics is used for the first and second recording layers 12 and 16, and there is a problem that an amount of light would be insufficient for an optical recording medium that is further multilayered. Further, the above-described prior art relates to a read-only memory (ROM) in which information is recorded previously. Thus, it is difficult to ensure the energy required for recording information so as to realize a recordable multilayer optical recording medium with this art.

Optical recording medium, optical information processor, and optical recording/reproducing method


An optical system includes a light source 102 disposed for generating light preferably in a line. An optical element 104 includes a stepped reflecting surface 106 that includes reflecting surfaces 132 and step surfaces 130. The reflecting surfaces 132 have a metalized coating thereon so that the plurality of metalized reflecting surfaces reflect light therefrom. Each reflecting surface is a circular sector that increases in radius from an adjacent circular sector.

Conventional lighting systems used in automotive vehicle applications such as headlights, taillights, and active night vision systems utilize an incandescent bulb with a reflector. The light emitted by the incandescent bulb is generally collimated by the reflector. The incandescent bulb may be used to generate light in the visible spectrum for headlight and taillight applications. Active night vision systems typically require near-infrared emissions that are compatible with solid state CCD or CMOS cameras to illuminate the scenery.
Advances in solid state lasers have given rise to thin-sheet lighting systems for use in taillight and active night vision systems. The thin-sheet systems require less space than bulb-and-reflector systems. Furthermore, laser diodes are more energy efficient and reliable than incandescent bulbs. A challenge in thin-sheet lighting systems is to rapidly spread the laser light over a sufficiently wide area to meet spatial illumination and eye safety requirements required under law. Many different approaches have been suggested to expand the point source of laser light uniformly over several square inches of an exterior optical surface.
U.S. Pat. No. 5,791,757, issued to O'Neil et al. on Aug. 11, 1998, discloses a lighting system that uses a uniform thickness thin-sheet optical element. This optical element has a plurality of micro-optical wedges that collimate and direct divergent laser light emitted from multiple fiber optic bundles. Diffractive optical elements are disposed intermediate the thin-sheet and fiber optics to direct the laser light to predetermined regions of the plurality of micro-optical wedges. The diffractive optical elements guide the light to the micro-optical wedges either in a direct path, or by bouncing the light off the exterior side of the thin-sheet opposite the micro-optical wedges. The optical efficiency of this approach could be improved upon if the diffractive optical element could be eliminated. Design complexity could be reduced if each of the micro-optical wedges did not have to be designed to receive the light from a different incident angle.
U.S. Pat. No. 6,422,713 describes a solid optical element that uses total internal reflection to reflect light from various facets. The light is projected into the optical element and projected outwardly by the facets. The optical element may be made of a plastic material. One drawback to this is that some plastic materials absorb light in the infrared range desirable for use in night vision illumination.
Therefore, it would be desirable to provide an optical structure that does not rely on internal reflection for distributing light in the infrared range.


A piezoelectric ceramic composition includes a primary component represented by the formula (1-x)(K1-a-bNaaLib)m(Nb1-c-dTacSbd)O3-xM1nM2O3, and 0.1 to 10 moles (preferably 1.5 to 10 moles) of at least one specific element selected from the group consisting of In, Sc, Y, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, and Lu with respect to 100 moles of the primary component, wherein M1 is Ca, Sr, or Ba M2 is Ti, Zr, or Sn; and x, a, b, c, d, m, and n satisfy 0.005≦x≦0.1, 0≦a≦0.9, 0≦b≦0.3, 0≦a+b≦0.9, 0≦c≦0.5, 0≦d≦0.1, 0.9≦m≦1.1, and 0.9≦n≦1.1. Preferably, Mn, Ni, Fe, Zn, Cu, or Mg is further added. As a result, at both a very low and a high electric field, a high piezoelectric d constant can be stably obtained with a high efficiency.

In recent years, in consideration of environmental conservation, attention has been paid to a lead-free piezoelectric ceramic composition which contains no Pb; however, it has been known that a piezoelectric d constant of the lead-free piezoelectric ceramic composition is generally low as compared to that of a lead-based piezoelectric ceramic composition such as PZT (PbTiO3—PbZrO3).
Under circumstances as described above, since a (K,Na)NbO3-based piezoelectric ceramic composition has a relatively high piezoelectric d constant (piezoelectric strain constant) among lead-free piezoelectric ceramic compositions, research and development of the (K,Na)NbO3-based piezoelectric ceramic composition has been aggressively carried out.
For example, in Patent Document 1, a piezoelectric ceramic composition has been disclosed which contains a primary component represented by the general formula of (1-n)(K1-x-yNaxLiy)m(Nb1-zTaz)O3-nM1M2O3 (where M1 is a divalent metal element, and M2 is a tetravalent metal element), and in Patent Document 2, a piezoelectric ceramic composition has been disclosed which contains a primary component represented by the general formula of (1-n)(K1-x-yNaxLiy)m(Nb1-zTaz)O3-nM1M2M3O3 (where M1 is a trivalent metal element, M2 is a monovalent metal element, and M3 is a tetravalent metal element). In addition, in both Patent Documents 1 and 2, x, y, z, m, and n are adjusted so as to satisfy 0.1≦x, y≦0.3, x+y<0.75, 0≦z≦0.3, 0.98≦m≦1.0, and 0<n<0.1.
According to Patent Documents 1 and 2, when a predetermined number of moles of a perovskite composite oxide M1M2O3 or M1M2M3O3 (such as BaTiO3, CaTiO3, or (Na0.5Bi0.5)TiO3) is solid-dissolved as a third component in (K,Na,Li) (Nb,Ta)O3, a piezoelectric ceramic composition is obtained which has a relative dielectric constant ∈r (=∈T/∈0; ∈T represents the absolute dielectric constant, and ∈0 represents the vacuum dielectric constant) of 1,000 or more, an electromechanical coupling factor kp of 25% or more, and a Curie point Tc of more than 200° C.
In addition, in Patent Document 3, a piezoelectric ceramic composition has been disclose which contains 0.005 to 0.15 moles of at least one metal element selected from the group consisting of Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir, La, Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, Si, Sm, Sn, Sr, Tb, Ti, Tm, V, Y, Yb, Zn, and Zr with respect to 1 mole of a primary component represented by {Lix(K1-yNay)1-x}(Nb1-z-wTazSbw)O3 (where 0≦x≦0.2, 0≦y≦1, 0<z≦0.4, and 0<w≦0.2) and which has an open porosity of 0.4 percent by volume or less.
According to Patent Document 3, it has been disclosed that when the open porosity (the amount of dimples generated in the surface of the piezoelectric ceramic composition is represented by volume percent) is controlled to be 0.4 percent by volume or less by addition of the above Ag to Zr metal elements, the mechanical strength can be improved. In addition, since the composition represented by the general formula of {Lix(K1-yNay)1-x}(Nb1-z-wTazSbw)O3 is the primary component, by using superior piezoelectric d constant and electromechanical coupling factor kp of the compound represented by the above general formula, a piezoelectric ceramic composition having superior properties described above can be obtained.
In Patent Document 4, a piezoelectric ceramic composition has been disclosed which is represented by {(K1-xNax)1-yAgy}NbO3-z[Mα+][O2−]α/2 (where 0≦x≦1, 0≦y≦0.1, 0≦z≦0.05, and 0<y+z; Mn is at least one metal element selected from the group consisting of Mn, Mg, In, Si, Ga, and Sb; and α is an average valance of metal element M).
According to this Patent Document 4, by addition of predetermined amounts Ag and at least one metal element selected from the group consisting of Mn, Mg, In, Si, Ga, and Sb to (K,Na)NbO3, besides a decrease in the dielectric loss, that is, tan δ, and improvement in reliability, the piezoelectric d constant can be improved.
Patent Document 1: Japanese Unexamined Patent Application Publication No. 11-228227
Patent Document 2: Japanese Unexamined Patent Application Publication No. 11-228228
Patent Document 3: Japanese Unexamined Patent Application Publication No. 2004-244300
Patent Document 4: Japanese Unexamined Patent Application Publication No. 2002-68835
According to Patent Documents 1 and 2, a high relative dielectric constant ∈r of 1,000 or more is obtained by addition of M1M2O3 or M1M2M3O3 as a third component to (K,Na,Li)(Nb,Ta)O3; however, when the content of the above third component is increased, since the electromechanical coupling factor kp is decreased, although an increase in piezoelectric d constant is slightly observed, the increase is not yet sufficient.
That is, among the piezoelectric d constant, the dielectric constant ∈T, and the electromechanical coupling factor kp, the following equation (1) holds.
[Equation 1]
                    d        =                  kp                                                              ɛ                T                            Y                                                          (        1        )
In the above equation, Y indicates Young's modulus.
Accordingly, in order to obtain a high piezoelectric d constant, the relative dielectric constant ∈r and the electromechanical coupling factor kp are both preferably increased; however, as described in Patent Documents 1 and 2, when only M1M2O3 or M3M4M2O3 is simply added as a third component to (K,Na,Li)(Nb,Ta)O3, the electromechanical coupling factor kp is decreased as the content of the third component is increased, and even if the relative dielectric constant ∈r can be increased, there has been a problem in that a desired sufficiently high piezoelectric d constant cannot be obtained.
In addition, according to Patent Document 3, the open porosity can be suppressed to 0.4 percent by volume or less by addition of a metal element, such as In, to {Lix(K1-yNay)1-x} (Nb1-z-wTazSbw)O3; however, according to an experiment carried out by the inventors of the present invention, a significant improvement in piezoelectric d constant could not be observed, and it was found that a piezoelectric ceramic composition having a desired high piezoelectric d constant cannot be obtained.
In addition, according to Patent Document 4, by addition of Ag, and In or the like to (K,Na)NbO3, d31 is improved; however, the improving rate is small, and it was found that a piezoelectric ceramic composition having a sufficiently high piezoelectric d constant cannot be obtained.
In addition, in recent years, concomitant with development of a technique to decrease a ceramic layer thickness, a multilayer piezoelectric ceramic electronic component driven by a high electric field has been developed and has been practically used.
In addition, as a piezoelectric material for a multilayer piezoelectric ceramic electronic component driven by a high electric field, a material having a high piezoelectric d constant at a high electric field, which is an electric field to be actually used, is preferable.
However, in general, a piezoelectric d constant at a high electric field, that is, at a practical electric field, and a piezoelectric d constant at a very low electric field, which is usually measured, are different from each other. Although the piezoelectric d constant at a very low electric field is high, the piezoelectric d constant at a high electric field is not always high.
That is, a piezoelectric material is composed of many regions, which are called domains, having different spontaneous polarization directions. In addition, at a very low electric field, only 180° domains respond which have a spontaneous polarization direction parallel to the direction of an applied electric field. On the other hand, at a high electric field, besides the response of the 1800 domains, since 90° domains, which have a spontaneous polarization direction perpendicular to the applied electric field direction, rotate toward the direction of the applied electric field, so that a large strain is generated; hence, as a result, a piezoelectric d constant which is higher than that at a very low electric field can be obtained. However, at a high electric field which is more than a certain predetermined electric field, since most of the 90° domains fully rotate and become 180° domains, a large displacement cannot be obtained. In addition, since the domain structure may vary with a material composition, although a material having a high piezoelectric d constant at a very low electric field is used, by the influence of the domain structure, the piezoelectric d constant at a high electric field may not be so much higher than expected in some cases.

Piezoelectric ceramic composition, method for manufacturing the same, and piezoelectric ceramic electronic component


In resin-molded engine control unit, a coil, an electrolytic capacitor, a microprocessor, electronic parts and a connector terminal are mounted on a board. Inside a cover fixed on the board, a resin-free region is formed. The coil, the electrolytic capacitor and the microprocessor, which should not be sealed with resin, are mounted in the resin-free region, while the board and the electronic parts which are not capped by the cover are sealed with a resin.

The present invention relates to the structures of module units having electronic parts and waterproof connectors mounted on circuit boards and encapsulated therein by resin molding. In particular, the invention relates to a structure suitable for engine control units and other electronic control units installed in automobiles, ships, agricultural machines, engineering machines, electric generators, etc.
Recently, the thermal environments of engine control modules (hereinafter, denoted as "engine control units") used in automobiles, ships, agricultural machines, engineering machines and electric generators are getting harsher and harsher.
That is, the situation is: (1) while they were conventionally installed in cabins, installation in engine compartments and on-engine mount are becoming popular, exposing engine control units to higher temperatures; (2) the amounts of heat generated by engine control units are increasing due to the increasing load current to be controlled; and (3) due to their downsizing, the amounts of heat generated by engine control units are increasing per unit volume as well.
Conventionally, typical engine control units employ a non-watertight structure comprising a printed circuit board having electronic parts mounted thereon and a case to cover them. For installation in engine compartments, inexpensive engine control units have appeared with cases which are structurally improved in heat radiation and resistance.
However, on-engine mount units are used in a still harsher thermal environment. They are required to endure 120° C. or higher temperatures. Engine control units for installation in engine compartments cannot operate at temperatures higher than 100° C. and therefore can not cope with such an environment.
Although there are engine control units which employ a high heat radiation structure comprising a ceramic board and bare chips, this structure is expensive as compared to the conventional structure.
As a conventional technology to solve these problems, Japanese Patent Laid-Open No. 2004-111435 discloses a resin-molded high heat radiation and high reliability engine control unit capable of enduring higher temperatures and higher thermal dissipation.
In addition, Japanese Patent Laid-Open No. 1996-70066 discloses a structure in which a cavity is provided on only one side of a circuit board in a semiconductor device.
The conventional technology of Japanese Patent Laid-Open No. 2004-111435, which encapsulates all electronic parts by resin molding, has various problems.
For example, the internal electrolytic solution of an electrolytic capacitor used in an engine control unit usually causes a small amount of leakage to the outside due to gasification. Therefore, if the electrolytic capacitor is sealed with resin, the gasified electrolyte solution accumulates near an electrode of the electrolytic capacitor and may result in causing a short circuit. Although an electrolytic capacitor is usually provided with an explosion-protection valve to release the gas pressure, the gas pressure may rise since this function is disabled if the electrolytic capacitor is sealed with resin. Therefore, using this conventional technology with electrolytic capacitors is not practical.
Although ceramic capacitors, tantalum capacitors and like can be used as substitutes, they are expensive and have a disadvantage in terms of cost. In addition, while common rail systems are becoming popular for low-emission diesel engines in Europe, their engine control units must contain capacitors having large capacitance values which neither the ceramic capacitor nor the tantalum capacitor can have. Therefore, this requirement can not be met if the control unit is encapsulated simply by resin molding.
In addition, large coils used in engine control units are likely to change in properties if they are sealed with resin. Therefore, it is not preferable to seal coils with resin in resin-molded engine control units.
Further, each electronic control unit is recently required to be provided with a self-diagnosis function to detect abnormality in the system. If the system malfunctions, the system must record details of the abnormality in an internal storage device to allow later investigation. However, if the electronic unit is encapsulated by resin molding, it is not possible to probe or visually inspect the internal circuit and electronic elements after the occurrence of a trouble in the electronic circuit. This makes it difficult to determine the causes of abnormalities of the system.
In the case of Japanese Patent Laid-Open No. 1996-70066 which discloses a structure where a cavity is provided on only one side of the circuit board, it is not possible to contain large electronic parts such as pin insertion type ones although this is effective to semiconductor and other small parts.

Electronic control unit and method thereof


A packaging assembly including a sealing station for sealing a product with at least one film web, wherein a printer is provided upstream of the sealing station and configured to print information, in particular a product weight and an associated retail price, onto the film web or onto a label, which may already be present on the film web, wherein, upstream of the sealing station, a forward weighing device is provided and configured to detect a weight value of a product and forward it to a control unit. The packaging assembly is characterized in that the control unit controls the printer for printing-on the information depending on the detected weight value, and that, downstream of the sealing station, at least a first inspection device is provided to read the information on the imprint. A method for making the packaging assembly is also included.

EP 2281749 A1 discloses a thermoform packaging machine comprising a weighing unit in the infeed area, so as to ascertain the weight of products, which are then manually fed into the packaging troughs. The packaging trough into which the product taken from the scales is to be fed is indicated to the operator by a signal, and a monitoring unit monitors this process so as to ensure that the product in question has been fed into the packaging trough intended for this purpose. This course of action aims at ensuring that the information of the weight of the respective trough matches the information printed on a top film, the information being printed onto the top film before the latter closes the packaging troughs in a sealing station. It is impossible to detect if products should be removed or exchanged on the conveying path between the infeed area and the sealing station. This concept does not allow compliance with certain guidelines for calibrated weighing and approved pricing.
DE 102005018251 A1 discloses a tray sealer, in the case of which, after sealing, the packages are transferred to a weighing belt, so as to ascertain the specific weight of each package. Subsequently, the weighed package is transmitted to a marking belt and provided with a label on the upper side of the package. The label comprises weight and price information, said information being transmitted to a printer on the label dispenser. The concept according to which a package that has already been closed is weighed and provided with price information immediately after weighing corresponds, on the machine-side, to the admission to pricing, provided that the weighing belt and the marking belt cannot be accessed from outside.

MULTIVAC MARKING & INSPECTION GMBH & CO. KG


Apparatus, methods, system and devices for providing a high efficiency parallel post regulator for a wide range input DC/DC converter. The wide input range DC/DC converter achieves zero-voltage-switching in the primary side switches in full range load due to 0.5 duty cycle of the operation at full load. The DC/DC converter reduces voltage stresses across main rectifiers, has a smaller conduction losses compared with conventional post regulators and the requirement of input and output filters is significantly reduced due to the filtered waveforms produced.

Range winding topology activates to increase the transformer turn-ratio for hold up time when the input DC voltage drops to certain value, so the converter is only required to be designed for narrow range input and it operates with large duty cycle with easy soft switching in the primary side resulting in good efficiency. At the same time range winding topology needs small current rating components because only certain hold up time, such as 20 ms, is its operation. However, transient problems occur during range winding activation because of the nonlinearity of range winding topology performance and the limitation of the close-loop bandwidth.
Conventional secondary side post regulators (SSPR) control the pulse width to regulate the tight output voltage and the primary side switches operate at 0.5 duty cycle, resulting in very easy conditions for soft switching in the primary side. But post regulators introduce extra conduction loss in the secondary side. Also post regulators cannot reduce the voltage stress across the secondary side rectifiers in wide range input DC/DC converter because the converter is required to be designed in the lowest DC input voltage and operates in the highest DC input voltage, so the efficiency resulting from the use of a conventional post regulator is poor.
In medium power rating converters, a half bridge converter is attractive because of its simplicity and low transformer turn-ratio. In wide range input DC/DC converters, conventional half bridge does not achieve zero voltage switching (ZVS) in the primary side because of small duty cycle operation. Asymmetrical half bridge converter and duty cycle shifting (DCS) control can achieve ZVS under certain conditions, but it does not provide ZVS in full range loads. In wide range input conditions, the efficiency of the half bridge converter is low. The best efficiency of isolated converters such as half bridge, full bridge and push pull topologies, exist in the conditions of approximately 0.5 duty cycle in the primary side, there is still the problem of regulating the output voltage.
Generally, wide range input DC/DC converters are designed at the minimum input voltage Vin min and always operates at the maximum input voltage Vin max with a small duty cycle, which makes very difficult to achieve soft switching in the primary side switch while achieving higher voltage stresses in the secondary rectifier that have large conduction and switching losses, so that the resulting converter has low efficiency.
FIG. 1 is a graph showing the operational point and design points for prior art front end DC/DC converters. With a requirement for a holdup time when the line input dropout occurs, the converter has to provide the regulated output voltage during holdup time, which means front end DC/DC converter has to operate in wide range input voltage between maximum and minimum voltage as shown on the graph. Most of time the converter operates at high input Vin max, and it only operates for very short holdup time when AC line dropout. So the converter should be designed in lowest voltage Vin min and it operates in high input voltage Vin max with very small duty cycle, which makes it very difficult to achieve soft switching and high voltage stresses across the secondary side rectifiers, all of those result in low efficiency in wide range input DC/DC converter.
FIG. 2 shows an example of a prior art half bridge converter and FIGS. 3a, 3b and 3c show different types of conventional prior art secondary side post regulators. FIG. 3d shows the range winding topology. Secondary side post regulators regulate the output voltage using secondary side control and the primary side easily achieves zero-voltage-switching in full range load due to 50% duty cycle operation. Main rectifiers are composed of rectifiers D1 and D2, filter Lf and output capacitor Co and the post regulator composed of rectifiers D3, D4 and switches Q3 and Q4.
In FIG. 3a, switches Q3 and Q4 are connected in series with the main rectifiers to control the pulse width for tight regulation of the output voltage with ZVS if the switches turn on or off at the intervals of main rectifiers' current commutation, but this series type SSPR it introduces large conduction loss due to large current ratings in the current path especially in low voltage applications. At the same time, this series type SSPR cannot reduce the voltage rating across the main rectifiers in wide range input converter in wide range input converter.
In FIG. 3b, switches Q3 and Q4 are series with D1 and D2 respectively and they can achieve ZCS. However, this is a cascade system so total converter efficiency is a concern during design. Also the cascade system cannot reduce the voltage rating across the main rectifiers in a wide range input converter.
The schematic diagram of FIG. 3c shows a combination of the topology of FIG. 3b and the rectifier in FIG. 1 to reduce the output filter inductance and to reduce the voltage rating across the main rectifiers in a wide range input converter. However, the combination increases conduction losses in primary side switches and post regulator because of the high current rating in the current path when the post regulator is activated.
In FIG. 3d, switch Q3 of range winding topology turns on when primary input voltage drops to certain value, the increased transformer turn ratio extends the hold up time so that the range winding topology can be designed in narrow input range. However, the transient response is the problem because of nonlinearity of range winding topology and bandwidth limitation.

High efficiency parallel post regulator for wide range input DC/DC converter

University of Central Florida Research Foundation, Inc.


A power source equipment (PSE) controller exhibiting low standby levels for power over Ethernet (PoE) includes a micro-controller, a detection and classification circuitry coupled to the micro-controller to detect if a powered device (PD) is connected and determine power needed to operate the connected PD, a power control and monitor circuitry coupled to the micro-controller to power the connected PD and to monitor the power consumption of the PD. The detection and classification circuitry, the power control and monitor circuitry can be individually turned off by the micro-controller to minimize standby power, the micro-controller can be put into deep sleep if no PD is detected or can be come out of deep sleep if a PD is detected.

Power over Ethernet (PoE) describes standard systems which pass electric power in parallel to data over twisted pair Ethernet cabling. This allows a single cable to provide both data connection and electric power to devices such as wireless access points, security network cameras, IP (Internet Protocol) phones and other IP-based terminals.
Ethernet communications provide high speed data communications over a communications link between two communications nodes that operates according the IEEE (The Institution of Electrical and Electronic Engineers, Inc.) 802.3 Ethernet Standard. The communications medium between the two nodes can be twisted pair wires for Ethernet, or other types communications medium that are appropriate. Power over Ethernet (PoE) communication systems provide power and data communications over a common communications link. More specifically, a power source device (PSE) connected to the physical layer of the first node of the communications link provides DC power (for example, 56 volts DC) to a powered device (PD) at the second node of the communications link. The DC power is transmitted simultaneously over the same communications medium with the high-speed data from one node to the other node.
In a PoE system, its power is supplied in common mode over two or more of the differential pairs of wires found in the Ethernet cable and comes from a power supply within a PoE-enabled networking device, such as an Ethernet switch, or can be injected into a cable run with a midspan power supply. A midspan power supply, or called a PoE power injector, is an additional PoE power source that can be used in combination with an non-PoE switch. In general, endpoint PSEs place their power onto the data pair of wires in the cable, while midspan PSEs are restricted to using spare pair of wires. Here, three variants of PoE as contemplated by the IEEE 802.3af standard, as illustrated in FIGS. 1A, 1B and 1C, just used as examples for demonstrating possible PoE configurations. In FIG. 1A a data telecommunications networks 10 comprises a switch or hub 3 with integral PSE 5. Power from the PSE 5 is injected on the two data carrying Ethernet twisted pairs 9a and 9b via center-tapped transformers 7a and 7b. Non-data carrying Ethernet twisted pairs 9c and 9d are unused in this variant. The power from data carrying Ethernet twisted pairs 9a and 9b is conducted from center-tapped transformers 7c and 7d to PD 13 for use. In FIG. 1B a data communications network 20 comprises a switch or hub 3a with integral PSE 15. Power from the PSE 15 is injected on the two non-data carrying Ethernet twisted pairs 19c and 19d. Data carrying Ethernet twisted pairs 19a and 19b are unused in this variant for power transfer. The power from non-data carrying Ethernet twisted pairs 19c and 19d is conducted to PD 23 for use as shown. In FIG. 1C a data communications network 30 comprises a switch or hub 3b without integral PSE. Midspan power insertion equipment 31 simply pass the data signals on the two data carrying Ethernet twisted pairs 29a-1 and 29b-1 to corresponding data carrying Ethernet twisted pairs 29a-2 and 29b-2. Power from the PSE 25 located in the midspan power insertion equipment 31 is injected on the two non-data carrying Ethernet twisted pairs 29c-2 and 29d-2 as shown. The power from non-data carrying Ethernet twisted pairs 29c-2 and 29d-2 is conducted to PD 33 for use as shown. The powered end stations 11, 11a and 11b are all the same so that they can achieve compatibility with each of the previously described variants.
In the PoE system, the PSE can be configured in a variety of standard as well as non-standard modes for delivering various levels or classes of power. Each of the IEEE 802.3af and 802.3at standards contains specifications and configuration details. One part of each standards provides each PSE a mechanism to detect the presence of a PD at a network port, such as by sensing the resistance of a PD. For example, the PSE can detect whether a PD is attached as part of a start-up procedure before applying power. FIG. 2A-B depicts an example of a block diagram of the conventional control from the PSE section of an IC-based PoE system.
FIG. 2A depicts an IC-based PoE system, it includes a PSE device 201 and a PD 203 that electrically coupled via an Ethernet connection. In the example of FIG. 2A the Ethernet connection is demonstrated as RJ-45 connector and category 5e (CAT5E) cable that implement four twisted pair conductors including two communication ports. The PSE device 201 includes a voltage source 205 that is configured to generate a voltage signal. The PSE device 201 further includes a PSE controller 207 which performs the power management functions based on the dynamic needs of the PD 203. Further, the PSE controller 207 detects and validates a compatible PD 203, determines a power classification signature for the validated PD 203, supplies power to the PD 203, monitors the power, and reduces or removes power from the PD 203 when the power is no longer requested or required. The PD 203 includes a pair of rectifiers 209 that are each coupled to the Ethernet connection at the respective ports. The rectifiers 209 are configured to provide the voltage signal to PD 203. The PD further includes a PD controller 211 that monitors the voltage and current on the PD 203 side of the PoE configuration. The PD controller 211 further provides the necessary impedance signatures on the return path during initialization. A DC-DC converter 213 may be optionally insert before the load been attached to step down the voltage as necessary to meet the voltage requirements of the PD 203.
FIG. 2B shows the block diagram of the output control circuit for one PSE channel. The PSE micro-controller 207 provide a gate signal (pass control) to modulate the impedance of the circuit breaker MOSFET (not shown) in each output channel. By controlling the MOSFET impedance, the output voltage of each channel can be tailed to perform detection, classification, full power application and power removal via PSE sensing and control circuit 215. Current and voltage sensors provide continuous feedback signals, i.e. Isense and Vsense respectively, for the PSE micro-controller 207 to supervise and execute the power management according to IEEE 802.3af specifications.
PoE technology is continuing to evolve. The PD power limitation outlined in IEEE 802.3af of 13 W is becoming inadequate for some new applications. Next-generation PoE applications will call for more power to support demanding features, and at the same time demand increased power efficiency in an effort to be more "green" and reduce costs. In early 2016 the department of energy (DOE) of the USA and Europe Union (EU) code of conduct (COC) officially enacted regulations, i.e. DOE level VI and COC tier II respectively, to increase the average efficiency of external power sources (EPS) and to lower standby levels. The lower standby levels for both the DOE level VI and COC tier II are very difficult to meet for active/IEEE802.3 based POEs. In order to meet the requirements, the PoE related circuitry needs to be shut down or removed and software needs to go into deep sleep. Therefore, in order to pass the standby requirements of the DOE level VI and COC tier II design changes for low standby power circuit architecture of PoE operation need to be addressed.

Low standby power circuit architecture for power saving within power source equipment


The present invention generally features therapeutic and diagnostic compositions and methods for increasing or decreasing the binding of a lysozyme polypeptide to a Treponema pallidum P17 polypeptide (Tp17) or a Tp17-like polypeptide. More particularly, the invention relates to compositions and methods for detecting, treating, or preventing a pathogen infection or a chronic disorder; and to binding assays using a Tp17-like polypeptide and a lysozyme polypeptide.

Syphilis is a disease caused by Treponema pallidum (hereinafter also referred to as "Tp") infection. The diagnosis of syphilis is generally made by an immunoassay of anti-Tp antibody in the blood using, for example, the Treponema pallidum Hemagglutination Test (TPHA), the Fluorescent Treponema Antibody Absorption Test (FTA-ABS) and/or the Treponema pallidum Immobilization Test (TPI), as well as enzyme-linked immuno sorbent assay (ELISA) and Western Blot systems. These tests detect antibodies that react with Tp or antigen preparations from Tp, such as the Tp antigens Tp15, Tp17, and Tp47, for example. The TPI test involves a microscopic assessment of the extent to which complement activating antibodies in a patient's serum inhibit the mobility of Tp. This test is not generally used as a diagnostic due to its high cost. The TPHA test involves agglutination of patient serum antibodies with erythrocytes to which the Tp sonicate antigen is bound. The FTA-ABS test involves indirect immunofluorescence microscopy to detect the binding of specific antibodies in patient serum to Tp attached to a solid support via a fluorescent-labelled secondary antibody. Although these assays are widely used, they lack the sensitivity required for detecting early stage or low level infection, when Tp antibody levels in the body fluids are very low.
In addition, the popular use of individual recombinant or purified Tp antigens in existing immunoassays for syphilis does not account for the binding by some antibodies to complexes formed between Tp antigens and other antigens (i.e., Tp antigen binding partners) normally present in the subject's body fluid. Existing immunoassays thus fail to detect such antibodies in the absence of the Tp antigen binding partner, which results in some instances in low sensitivity or false negative assay results. A need therefore exists for pathogen diagnostic assays with improved sensitivity, which detect antibodies that bind to pathogen antigen/binding partner complexes.

Compositions and kits for detecting pathogen infection


Methods of treating a subject who has an tissue damage or who is at risk for tissue necrosis are disclosed. Also disclosed are methods of treating a subject who has an inflammatory disorder. The methods can include administering to the subject a pharmaceutical composition comprising inorganic nitrite or a pharmaceutically acceptable salt thereof, for a time and in an amount sufficient to reduce the tissue damage. The subject can be diagnosed as having a medical condition that results tissue damage, for example, diabetes, peripheral artery disease, cardiovascular disease, defective wound healing, arthritis, inflammatory bowel disease, ischemia, or a bacterial infection, e.g., Group A staphylococcal infection. The methods can include the step of monitoring the course of treatment.

Multicellular organisms are made up of tissues, i.e., organized aggregates of specialized groups of cells of similar form and function. Animal tissues include connective tissue, muscle tissue, nervous tissue and epithelial tissue. Regardless of the kind of tissue, tissue damage, whether by infection, trauma, or disease, contributes significantly to human morbidity and mortality. There is a continuing need for therapeutic strategies that lead to successful treatment of damaged tissue.

This patent is subject to a terminal disclaimer.

Use of nitrite salts in treating tissue damage

Board of Supervisors of Louisiana State University and Agricultural and Mechanical college


The present invention relates to a projection apparatus in which a beam of light from light source means is separated into beams of two polarized components by a polarization separator, and the direction of polarization of one of the separated beams of two polarized components is caused to coincide with the direction of polarization of the other beam of light through polarizing rotatable means, whereafter the two beams of light are condensed by a condenser of which the refractive power differs between two directions orthogonal to each other, a projected image is irradiated with the beam of light passed through the condenser and the projected image is projected onto a predetermined surface by a projector.

1. Field of the Invention
This invention relates to an illuminating device and a projection apparatus using the same, and is particularly suitable for an apparatus such as a slide projector or a liquid crystal projector adapted to achieve the effective utilization of a beam of light from a light source, illuminate a projected image efficiently and project the projected image onto the surface of a screen by a projection lens.
2. Related Background Art
There have heretofore been proposed various projection apparatuses designed such that the original picture of a projected image displayed on film, a liquid crystal light valve (liquid crystal display element) or the like is magnified and projected onto the surface of a screen.
Of these, there have been proposed various projection apparatuses designed such that in order to enhance the utilization efficiency of light, beams of light from a light source are converted into a polarized beam of light which illuminates the liquid crystal display element.
FIG. 7 of the accompanying drawings is a plan view showing the essential portions of the optical system of a projection apparatus according to the conventional art, and FIG. 8 of the accompanying drawings is a side view showing the essential portions of FIG. 7. These figures shows a case where a transmission type liquid crystal panel (liquid crystal light valve) is used as a projected image 72 and this image is magnified and projected by a projection lens 71.
In FIGS. 7 and 8, the reference numeral 73 designates a white light source comprising, for example, a halogen lamp, a metal halide lamp or the like. The reference numeral 74 denotes a reflector comprising a parabolic or otherwise shaped reflecting surface, which effectively directs a beam of light from the white light source 73 toward a polarizing conversion element 70.
The polarization converting element 70 has the optical function of causing an incident beam of light to emerge as a polarized beam of light (P-polarized light). The polarizing conversion element 70 has a polarizing beam splitter 75 for transmitting P-polarized light therethrough and reflecting S-polarized light, a polarizing rotatable element 77 having a quarter wavelength plate and a reflecting surface for converting the S-polarized light from the polarized beam splitter 75 into P-polarized light and reflecting it, and a reflecting mirror 76.
In FIGS. 7 and 8, a beam of light La including the P-polarized light and S-polarized light from the light source 73 is made into two polarized lights P.sub.1 and P.sub.2 by the polarizing conversion element 70, and these P-polarized lights P.sub.1, and P.sub.2 are directed to a condenser lens 78, and a liquid crystal panel 72 is illuminated by a beam of light condensed by the condenser lens 78.
The reference numeral 71 designates a projection lens which projects an image displayed on the liquid crystal panel 72 onto a screen (not shown).
In the projection apparatus shown in FIGS. 7 and 8, the emergent light from the liquid crystal panel 72 is greatly widened in a plane containing both the normal to the polarizing beam splitter 75 and the normal to the reflecting mirror 76 (the plane of the drawing sheet of FIG. 7, hereinafter referred to as the "polarizing conversion plane").
On the other hand, the expanse of the beam of light in a plane perpendicular to the polarizing conversion plane (the plane of the drawing sheet of FIG. 8) is small as compared with that in the polarizing conversion plane. In the projection apparatus according to the conventional art, a beam of light of which the expanses in the polarizing conversion plane and a plane orthogonal thereto differ from each other has been condensed by the condenser lens 78 comprising a spherical lens and the liquid crystal panel 72 has been illuminated by this beam of light. This has led to the problem that the utilization efficiency of the beam of light is low.


An organopolysiloxane having monofunctional siloxane units (M unit) and tetrafunctional siloxane units (Q unit) and also having in the molecule an epoxy group-containing organic group, a polydiorganosiloxane residue bonded therein across a divalent hydrocarbon group, and optionally alkoxysilylalkyl is useful as an internal stress-relaxing agent, an internal mold-release, and as an adhesion promoter for curable organopolysiloxanes. These organopolysiloxanes are made by an addition reaction.

1. Technical Field
The present invention relates to organopolysiloxane and method for the preparation thereof. More specifically, the present invention relates to organopolysiloxane (i) that has monofunctional siloxane units (M unit) and tetrafunctional siloxane units (Q unit). (ii) that contains in each molecule at least one epoxy group-containing organic group, and (iii) that contains in each molecule at least one diorganopolysiloxane residue bonded therein through a divalent hydrocarbon group.
2. Prior Art
Various types of MQ organopolysiloxanes are already known in the art. Shirahata in U.S. Pat. No. 4,707,531, issued Nov. 17, 1987, describes a method of making MQ organopolysiloxanes which have long been used as starting materials for varnishes and pressure sensitive adhesives. According to Shirahata an alkyl silicate is dripped into a mixture of an aqueous hydrochloric acid which contains at least 5 weight percent hydrogen chloride and a trialkylsilane or a disiloxane at a temperature of 0.degree. to 90.degree. C. Shirahata and Fukutani in U.S. Pat. No. 4,946,921, issued Aug. 7, 1990, describe a hydroxyphenyl-containing MQ organopolysiloxane of the general formula ##STR1## where A is a hydroxyphenyl group. R' is an alkylene group having 1 to 4 carbon atoms, n is zero or one. R" is an alkyl group having 1 to 4 carbon atoms, x and z are positive numbers y is zero or a positive number, x, y, and z have values such that their ratios are 0.ltoreq.(x+y)/z.ltoreq.4, and zero.ltoreq.y/x.ltoreq.5.
Fukutani in U.S. Pat. No. 5,011,901, issued Apr. 30, 1991, describes a chloromethyl-containing MQ organopolysiloxane of the general formula ##STR2## where R' is a monovalent hydrocarbon group having 1 to 6 carbon atoms, R" is a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms, x and y are positive numbers, y is zero or a positive number, and x, y, and z have values such that their ratios are 0.3.ltoreq.(x+y)/z.ltoreq.4 and zero.ltoreq.y/x.ltoreq.100.
However, the groups bonded to the silicon in the monofunctional siloxane units (M unit) of these MQ organopolysiloxanes are limited to the hydrogen atom, alkyl, alkenyl hydroxyphenyl, and chloromethyl. There have been no reports of MQ organopolysiloxane in which the silicon in the monofunctional siloxane unit (M unit) carries both an epoxy-containing organic group and a polydiorganosiloxane residue bonded thereto through a divalent hydrocarbon group.
The present invention was developed as the result of extensive investigations by the present inventor in order to solve the preceding problem.

Epoxy-containing organopolysiloxane and method for the preparation thereof


A resuscitation device for automatic compression of a victim's chest using a compression belt operably attached to a platform upon which a patient rests. In use, the compression belt is wrapped around the patient and at least one spindle operably attached to the platform.

Cardiopulmonary resuscitation (CPR) is a well known and valuable method of first aid. CPR is used to resuscitate people who have suffered from cardiac arrest after heart attack, electric shock, chest injury and many other causes. During cardiac arrest, the heart stops pumping blood, and a person suffering cardiac arrest will soon suffer brain damage from lack of blood supply to the brain. Thus, CPR requires repetitive chest compression to squeeze the heart and the thoracic cavity to pump blood through the body. Very often, the patient is not breathing, and mouth to mouth artificial respiration or a bag valve mask is used to supply air to the lungs while the chest compression pumps blood through the body.
It has been widely noted that CPR and chest compression can save cardiac arrest patients, especially when applied immediately after cardiac arrest. Chest compression requires that the person providing chest compression repetitively push down on the sternum of the patient at 80 to 100 compressions per minute. CPR and closed chest compression can be used anywhere, wherever the cardiac arrest patient is stricken. In the field, away from the hospital, it may be accomplished by ill-trained bystanders or highly trained paramedics and ambulance personnel.
When a first aid provider performs chest compression effectively, blood flow in the body is typically about 25 to 30% of normal blood flow. This is enough blood flow to prevent brain damage. However, when chest compression is required for long periods of time, it is difficult if not impossible to maintain adequate compression of the heart and rib cage. Even experienced paramedics cannot maintain adequate chest compression for more than a few minutes. Hightower, et al., Decay In Quality Of Chest Compressions Over Time, 26 Ann. Emerg. Med. 300 (September 1995). Thus, long periods of CPR, when required, are not often successful at sustaining or reviving the patient. At the same time, it appears that, if chest compression could be adequately maintained, cardiac arrest victims could be sustained for extended periods of time. Occasional reports of extended CPR efforts (45 to 90 minutes) have been reported, with the victims eventually being saved by coronary bypass surgery. See Tovar, et al., Successful Myocardial Revascularization and Neurologic Recovery, 22 Texas Heart J. 271 (1995).
In efforts to provide better blood flow and increase the effectiveness of bystander resuscitation efforts, modifications of the basic CPR procedure have been proposed and used. Of primary concern in relation to the devices and methods set forth below are the various mechanical devices proposed for use in main operative activity of CPR, namely repetitive compression of the thoracic cavity.
The device shown in Barkolow, Cardiopulmonary Resuscitator Massager Pad, U.S. Pat. 4,570,615 (Feb. 18, 1986), the commercially available Thumper device, and other such devices, provide continuous automatic closed chest compression. Barkolow and others provide a piston which is placed over the chest cavity and supported by an arrangement of beams. The piston is placed over the sternum of a patient and set to repeatedly push downward on the chest under pneumatic power. The patient must first be installed into the device, and the height and stroke length of the piston must be adjusted for the patient before use, leading to delay in chest compression. Other analogous devices provide for hand operated piston action on the sternum. Everette, External Cardiac Compression Device, U.S. Pat. No. 5,257,619 (Nov. 2, 1993), for example, provides a simple chest pad mounted on a pivoting arm supported over a patient, which can be used to compress the chest by pushing down on the pivoting arm. These devices are not clinically more successful than manual chest compression. See Taylor, et al., External Cardiac Compression, A Randomized Comparison of Mechanical and Manual Techniques, 240 JAMA 644 (August 1978).
Other devices for mechanical compression of the chest provide a compressing piston which is secured in place over the sternum via vests or straps around the chest. Woudenberg, Cardiopulmonary Resuscitator, U.S. Pat. No. 4,664,098 (May 12, 1987) shows such a device which is powered with an air cylinder. Waide, et al., External Cardiac Massage Device, U.S. Pat. No. 5,399,148 (Mar. 21, 1995) shows another such device which is manually operated. In another variation of such devices, a vest or belt designed for placement around the chest is provided with pneumatic bladders which are filled to exert compressive forces on the chest. Scarberry, Apparatus for Application of Pressure to a Human Body, U.S. Pat. No. 5,222,478 (Jun. 29, 1993), and Halperin, Cardiopulmonary Resuscitation and Assisted Circulation System, U.S. Pat. No. 4,928,674 (May 29, 1990), show examples of such devices. Lach, et al., Resuscitation Method and Apparatus, U.S. Pat. No. 4,770,164 (Sep. 13, 1988), proposed compression of the chest with wide band and chocks on either side of the back, applying a side-to-side clasping action on the chest to compress the chest.
Several operating parameters are required for a successful resuscitation device. Chest compression must be accomplished vigorously if it is to be effective because very little of the effort exerted in chest compression actually compresses the heart and large arteries of the thorax and most of the effort goes into deforming the chest and rib cage. The force needed to provide effective chest compression, however, creates risk of other injuries. It is well known that placement of the hands over the sternum is required to avoid puncture of the heart during CPR. See Jones and Fletter, Complications After Cardiopulmonary Resuscitation, 12 Am. J. Emerg. Med. 687 (November 1994), which indicates that lacerations of the heart, coronary arteries, aortic aneurysm and rupture, fractured ribs, lung herniation, stomach and liver lacerations have been caused by CPR. Thus the risk of injury attendant to chest compression is high, and clearly may reduce the chances of survival of the patient vis-à-vis a resuscitation technique that could avoid those injuries. Further, chest compression will be completely ineffective for very large or obese cardiac arrest patients because the chest cannot be compressed enough to cause blood flow. Additionally, chest compression via pneumatic devices is hampered in its application to females due to the lack of provision for protecting the breasts from injury and applying compressive force to deformation of the thoracic cavity rather than the breasts.
CPR and chest compression should be initiated as quickly as possible after cardiac arrest to maximize its effectiveness and avoid neurologic damage due to lack of blood flow to the brain. Hypoxia sets in about two minutes after cardiac arrest, and brain damage is likely after about four minutes without blood flow to the brain. Further, the severity of neurologic defect increases rapidly with time. A delay of two or three minutes significantly decreases the chance of survival and increases the probability and severity of brain damage. However, CPR and ACLS are unlikely to be provided within this time frame. Response to cardiac arrest is generally considered to occur in four phases, including action by Bystander CPR, Basic Life Support, Advanced Cardiac Life Support, and the Emergency Room. Bystander CPR occurs, if at all, within the first few minutes after cardiac arrest. Basic Life Support is provided by First Responders who arrive on scene about 4 to 6 minutes after being dispatched to the scene. First responders include ambulance personnel, emergency medical technicians, firemen and police. They are generally capable of providing CPR but cannot provide drugs or intravascular access, defibrillation or intubation. Advanced Life Support is provided by paramedics or nurse practitioners who generally follow the first responders and arrive about 8 to 15 minutes after dispatch. ALS is provided by paramedics, nurse practitioners or emergency medical doctors who are generally capable of providing CPR, and drug therapy, including intravenous drug delivery, defibrillation and intubation. The ALS providers may work with a patient for twenty to thirty minutes on scene before transporting the patient to a nearby hospital. Though defibrillation and drug therapy are often successful in reviving and sustaining the patient, CPR is often ineffective even when performed by well trained first responders and ACLS personnel because chest compression becomes ineffective as the providers become fatigued. Thus, the initiation of CPR before arrival of first responders is critical to successful life support. Moreover, the assistance of a mechanical chest compression device during the Basic Life Support and Advanced Life Support stages is needed to maintain the effectiveness of CPR.

CPR assist device adapted for anterior/posterior compressions