In a RTP stream having a plurality of FEC frames containing source blocks of media packets, random access points are inserted in front of the source blocks so as to allow a media decoder to decode the media packets as soon as FEC decoding is finished. In particular, the media packets contain forward error correction (FEC) source blocks for a multimedia broadcast/multicast-based streaming service content. As the multimedia broadcast/multicast streaming service includes dynamic interactive multimedia scene content where the source RTP packets of different media along with the FEC RTP packets are transmitted as separate RTP streams, the inclusion of the random access point facilitates immediate rendering of the dynamic interactive multimedia scene content after FEC decoding, thus reducing the tune-in latency.

Most packet based communication networks, especially Internet Protocol (IP) networks without guaranteed quality of service, suffer from a variable amount of packet losses or errors. Those losses can stem from many sources, for example router or transmission segment overload or bit errors in packets that lead to their deletion. It should be understood that packet losses are a common operation point in most packet networks architectures, and not a network failure. Media transmission, especially the transmission of compressed video, suffers greatly from packet losses.
Annoying artifacts in a media presentation resulting from errors in a media transmission can further be avoided by many different means during the media coding process. However, adding redundancy bits during a media coding process is not possible for pre-coded content, and is normally less efficient than optimal protection mechanisms in the channel coding using a forward error correction (FEC).
Forward Error Correction works by calculating a number of redundant bits over the to-be-protected bits in the various to-be-protected media packets, add those bits to FEC packets, and transmit both, the media packets and the FEC packets. At the receiver, the FEC packets can be used to check the integrity of the media packets and to reconstruct media packets that may be missing. Henceforth, the media packets and the FEC packets which are protecting those media packets will be called a FEC frame. Examples of the FEC frame are shown in FIG. 1. As shown in FIG. 1, a media GOP stream 300 comprises a media GOP 310 and a media GOP 320 separated by a boundary 315. The FEC structure 500 comprises a FEC frame 510 and a FEC frame 520 separated by a boundary 515. In addition to the media packets 514, the FEC frame 510 also contains an FEC packet 512 and two padding packets 516. Likewise, the FEC frame 520 contains an FEC packet in addition to the media packets 524. As such, the FEC frames 510, 520 are generally longer than the media GOPs. As such, the FEC frames are not aligned with the media GOPs.
Most FEC schemes intended for error protection allow selecting the number of to-be-protected media packets and the number of FEC packets to be chosen adaptively to select the strength of the protection and the delay constraints of the FEC subsystem.
Packet based FEC in the sense discussed above requires a synchronization of the receiver to the FEC frame structure, in order to take advantage of the FEC. That is, a receiver has to buffer all media and FEC packets of a FEC frame before error correction can commence.
Video coding schemes, and increasingly some audio coding schemes, for example, use so-called predictive coding techniques. Such techniques predict the content of a later video picture or audio frame from previous pictures or audio frames, respectively. In the following, video pictures and audio frames will both be referred to as "pictures", in order to distinguish them from FEC frames. By using predictive coding techniques, the compression scheme can be very efficient, but becomes also increasingly vulnerable to errors the longer the prediction chain becomes. Hence, so-called key pictures, or the equivalent of non-predictively coded audio frames, both referred to as key pictures hereinafter, are inserted from time to time. This technique re-establishes the integrity of the prediction chain by using only non-predictive coding techniques. It is not uncommon that a key pictures is 5 to 20 times bigger than a predictively coded picture. Each encoded picture may correspond, for example, to one to-be-protected media packet.
Following the conventions of MPEG-2 visual, the picture sequence starting with a key picture and followed by zero or more non-key pictures is henceforth called Group of Pictures (GOP). In digital TV, a GOP consists normally of no more than six pictures. In streaming applications, however, GOP sizes are often chosen much bigger. Some GOPs can have hundred of pictures in a GOP in order to take advantage of the better coding efficiency of predictively coded pictures. For that reason, the "tune in" to such a sequence can take several seconds.
FEC schemes can be designed to be more efficient when FEC frames are big in size, for example, when they comprise some hundred packets. Similarly, most media coding schemes gain efficiency when choosing larger GOP sizes, since a GOP contains only one single key picture which is, statistically, much larger than the other pictures of the GOP. However, both large FEC frames and large GOP sizes are required to synchronize to their respective structures. For FEC frames this implies buffering of the whole FEC frame as received, and correcting any correctable errors. For media GOPs this implies the parsing and discarding of those media packets that do not form the start of a GOP (the key frame).
In U.S. Patent Application Publication No. 2006/0107189 A1, it is stated that, in order to reduce a buffer delay at a decoding end, the FEC frames should be aligned with the groups of media packets. To that end, the encoder should be able to determine, for a group of coded media packets contained in an FEC frame, the number of next subsequent groups of coded media packets which fit completing into that FEC frame, and to select all coded media packets associated with the group or groups of coded media packets so determined for that FEC frame. For alignment purposes, it is possible to equalize the size of selected packets by adding predetermined data to some of them. Examples of aligned FEC frames and the groups of media packets are shown in FIG. 2. As shown in FIG. 2, a media GOP stream 400 comprises a media GOP 410 and a media GOP 420 separated by a boundary 415. The FEC structure 600 comprises a FEC frame 610 and a FEC frame 620 separated by a boundary 615. Although the FEC frames 610 and 620 also contain FEC packets and the media packets, they can be made aligned with the GOPs.
FEC can be applied to rich media content. Rich media content is generally referred to content that is graphically rich and contains compound (or multiple media) including graphics, text, video and audio and preferably delivered through a single interface. Rich media dynamically changes over time and could respond to user interaction.
Streaming of rich media content is becoming more and more important for delivering visually rich content for real-time transport especially within the Multimedia Broadcast/Multicast Services (MBMS) and Packet-switched Streaming Services (PSSS) architectures in 3GPP. PSS provides a framework for Internet Protocol (IP) based streaming applications in 3G networks, especially over point-to-point bearers. MBMS streaming services facilitate resource efficient delivery of popular real-time content to multiple receivers in a 3G mobile environment. Instead of using different point-to-point (PtP) bearers to deliver the same content to different mobiles, a single point-to-multipoint (PtM) bearer is used to deliver the same content to different mobiles in a given cell. The streamed content may consist of video, audio, XML (eXtensible Markup Language) content such as Scalable Vector Graphics (SVG), timed-text and other supported media. The content may be pre-recorded or generated from a live feed. SVG allows for three types of graphic objects: vector graphic shapes, image and texts. Graphic objects can be grouped, transformed and composed from previously rendered objects. SVG content can be arranged in groups such that each of them can be processed and displayed independently from groups that are delivered later in time. Groups are also referred to as scenes.
Until recently, applications for mobile devices were text based with limited interactivity. However, as more wireless devices are coming equipped with color displays and more advanced graphics rendering libraries, consumers will demand a rich media experience from all their wireless applications. A real-time rich media content streaming service is imperative for mobile terminals, especially in the area of MBMS, PSS, and Multi-Media Streaming (MMS) services. Rich media applications particularly in the Web services domain include XML based content such as:
SVGT 1.2—is a language for describing two-dimensional graphics in XML. SVG allows for three types of graphic objects: vector graphic shapes (e.g., paths consisting of straight lines and curves), multimedia (such as raster images, video, video), and text. SVG drawings can be interactive (using DOM event model) and dynamic. Animations can be defined and triggered either declaratively (i.e., by embedding SVG animation elements in SVG content) or via scripting. Sophisticated applications of SVG are possible by use of a supplemental scripting language which accesses the SVG Micro Document Objects Module (μDOM), which provides complete access to all elements, attributes and properties. A rich set of event handles can be assigned to any SVG graphical object. Because of its compatibility and leveraging of other Web standards (such as CDF), features like scripting can be done on XHTML (Extensible HyperText Markup Language) and SVG elements simultaneously within the same Web page.SMIL 2.0—The Synchronized Multimedia Integration Language (SMIL) enables simple authoring of interactive audiovisual presentations. SMIL is typically used for "rich media"/multimedia presentations which integrate streaming audio and video with images, text or any other media type.CDF—The Compound Documents Format (CDF) working group is producing recommendations on combining separate component languages (e.g. XML-based languages, elements and attributes from separate vocabularies), like XHTML, SVG, MathML, and SMIL, with a focus on user interface markups. When combining user interface markups, specific problems have to be resolved that are not addressed by the individual markups specifications, such as the propagation of events across markups, the combination of rendering or the user interaction model with a combined document. The Compound Document Formats working group will address this type of problems. This work is divided in phases and two technical solutions: combining by reference and by inclusion.
In the current 3GPP DIMS (Dynamic Interactive Multimedia Scenes) activity, the streaming of DIMS content has been recognized as an important component of a dynamic rich media service for enabling real time, continuous realization of content at the client. A DIMS content stream typically consists of a series of RTP (Real-time Transport Protocol) packets whose payload is SVG scene, SVG scene update(s), and coded video and audio packets. These RTP packets are encapsulated by UDP (User Datagram Protocol)/IP headers and transmitted over the 3G networks. The packets may be lost due to transmission errors over the wireless links or buffer overflows at the intermediate routers of the 3G networks.
3GPP SA4 defined some media independent packet loss recovery mechanisms at transport layer and above in the MBMS and PSS frameworks. In MBMS, application layer FEC is used for packet loss recovery for both streaming and download services. In PSS, RTP layer retransmissions are used for packet loss recovery. For unicast download delivery, TCP (Transmission Control Protocol) takes care of the reliable delivery of the content.
For rich media based MBMS streaming services, it is very likely that the users tune-in to the service at arbitrary instants during the streaming session. The clients start receiving the packets as soon as they tune-in to the service and may have to wait for a certain time period to start decoding/rendering of the received rich media content. This time period is also called "tune-in delay". For good user experience, it is desirable that the clients start rendering the content as soon as possible from the time they receive the content. Thus one requirement of DIMS is to allow for efficient and quick tune-in of DIMS clients to the broadcast/multicast streaming service. Quick tune-in can be enabled by media level solutions, transport level solutions or a combination of the two.
When streaming rich media (DIMS) content over broadcast/multicast channels of the 3G wireless networks, it is essential to protect the content from packet losses by using application layer forward error correction (AL-FEC) mechanism. AL-FEC algorithm is typically applied over a source block of media RTP packets to generate redundant FEC RTP packets. As mentioned earlier and illustrated in FIGS. 1 and 2, the media and the associated FEC packets are collectively referred to as an "FEC frame". The FEC frame is transmitted over the lossy network. A receiver would be able to recover any lost media RTP packets if it receives sufficient total number of media and FEC RTP packets from that FEC frame. Currently, the length of the above-mentioned source block is configurable. AL-FEC is more effective if large source blocks are used. On the other hand, the tune-in delay is directly proportional to the length of the source block.
In a typical rich media streaming session that involves SVG, audio and video media, at the sender side, source RTP packets of each media are bundled together to form a source block for FEC protection. One or more FEC RTP packets are generated from this source block using an FEC encoding algorithm. The source RTP packets of different media along with the FEC RTP packets are transmitted as separate RTP streams, as shown in FIG. 3. As shown in FIG. 3, the DIMS RTP stream contains a plurality of FEC frames 6101, 6102 and 6103, for example. These FEC frames may contain the source blocks for different DIMS media or the same medium. The FEC frame 6101 comprises a source block 6141 of source RTP packets and a FEC RTP packet 6121. On the receiver side, the client buffers the received RTP packets (both source and FEC) for sufficient duration and tries to reconstruct the above mentioned source block. If any source RTP packets are missing, then it tries to recover them by applying the FEC decoding algorithm.
The length of the FEC source block is a critical factor in determining the tune-in delay. The client has to buffer for the duration of an entire FEC source block. If a client starts receiving data in the middle of the current FEC source block, then it may have to discard the data from the current source block, and wait to receive next source block from the beginning to the end. Hence on an average it has to wait for 1.5 times the FEC source block duration.
After FEC decoding, the packets are sent to various media decoders at the receiver. The media decoders may not be able to decode from arbitrary points in the compressed media bit stream. If the FEC frames and the media GOPs are not aligned, then on an average the decoder may have to discard one half of the current media GOP data.Tune-in delay=1.5*(FEC source block duration)+0.5*(media GOP duration)  (1),where FEC source block duration is the buffering delay of the FEC frame (in isochronous networks this is proportional to the size of the FEC frame), and media GOP duration is the buffering delay of the media GOP. The worst case buffer sizes have to be chosen such that a complete FEC frame and a complete GOP, respectively, fits into the buffer of an FEC decoder and the buffer of a media decoder, respectively.

Method and device for assembling forward error correction frames in multimedia streaming


A compressible hearing aid includes an exterior deformable skin which bounds an internal region which is filled, at least in part, with an open-cell foam, the foam can be wrapped around or molded to contain an audio output transducer. The skin is not self-supporting and in response to applied forces from user's ear canal, the skin and the foam both deform and readily compress exhibiting a reduced volume. Though compressed, the foam exerts an outward force against the skin thereby continuing to form an elongated seal between the skin and the external periphery of the user's dynamically changing ear canal. As the volume of the ear canal increases, the skin and open-cell foam expand, exhibiting an increased internal volume, while maintaining a comfortable seal with the ear canal. A plurality of external ribs carried on the skin not only reduces feedback but promotes drying of the ear canal and promotes retention of the hearing aid in the ear canal.

Hearing aid housings have long been molded using acrylic resins which when cured are rigid, and hard. These housings often require extensive after the fact adjusting in response to user complaints of poor fit and/or poor performance. Complaints with this type of housing substantially increase overall production costs. Each unsatisfactory hearing aid must be reworked, replaced or the charge refunded to the user.
One of the disadvantages of rigid shell aids is that they are non-compliant and may force the user's ear canal to assume an unnatural shape in the cartilaginous region of the canal in order to achieve a seal. This in time can cause user discomfort and discourage usage of the aid.
It has now been recognized that dynamic changes in the shape of a user's ear canal as the user talks, breaths or swallows produce a situation where a rigid hearing aid housing conforms to the shape of the user's ear canal in only one state. This is the state the ear canal was in when an ear impression was taken. All other states will produce an uncomfortable fit or one that does not seal properly thereby producing feedback. Some of these issues have been addressed in a publication, CIC Handbook, Chasin, Singular Publishing Group, Inc., San Diego, 1997, pg 1–55.
A variety of solutions have addressed the fitting problem. One solution is disclosed in Yoest Patent No. 6,167,141, based on Ser. No. 09/070,124 filed Apr. 30, 1998, assigned to the assignee hereof and incorporated herein by reference. In Yoest, protrusions on a compliant body contribute to a comfortable seal with the respective ear canal.
Another prior solution combined deformable ear tips with rigid standardized housings that are to be inserted into the tips. These solutions rely on the deformable tips to compensate for differences between the user's ear canal and the shape of the housing contained within the tip.
The ear tip solution has had only limited success The thickness of the tip relative to the size of the ear canal and the size of the housing carried therein have resulted in a structure which has limited bendability when inserted into or removed from the ear canal. Thus, this solution can not be used with convoluted ear canals.
Another attempted solution uses a solid elastomeric housing which carries the audio processing circuitry and the battery. Elastomers, when cured, while solid are soft and deformable.
Known solid elastomeric housings, while deformable, are substantially incompressible. Such housings exhibit a substantially constant volume. This results in a situation where portions of the ear canal may push against portions of the elastomeric housing, deforming same. However the elastomeric material pushes back against the adjacent periphery of the ear canal, since it is substantially incompressible. This process is known to produce ear pain at times. This will come about if part of the elastomeric material is adjacent to soft tissue in the ear canal.
Solid elastomeric housings require balancing softness of material with strength. Softer elastomers have lower tensile strengths and tend to rip where they are thin. While exhibiting softness, solid elastomeric housings must still have enough strength to protect internal electrical/electronic components.
It has also been known to combine a gas containing bladder with a housing for a hearing aid. The bladder is deformable and compressible. The bladder is filed with a fluid such as ambient air.
The bladder can be filled before or after insertion. When the ear canal applies compression force to the bladder, the fluid therein will also be compressed. This compression in turn will increase the pressure applied by the fluid to the interior of the bladder, and the adjacent tissue of the user's ear canal.
For a constant temperature, reducing bladder volume by 50% produces a corresponding increase in expansion pressure within the bladder and ultimately, an increased force is applied to the ear canal. This becomes uncomfortable and unacceptable to the users.
In another attempted solution, a hollow deformable hearing aid housing has been formed of a semi-rigid material with thick enough side walls to be insertable into an ear canal without buckling. One known hearing aid with a housing as described above has been publicly marketed in the U.S.A. since 1996. In this hearing aid, the internal components, such as the output transducer, a receiver, were positioned in a gas filled interior. For example, the internal volume could be filled with ambient air.
When the housing is deformed, ambient air therein is forced from the interior. This solution provides only limited flexibility in the housing, due to the thickness of the housing. Insertion rigidity is achieved with this hearing aid as a result of the thickness of the housing. Beyond the limited flexibility, no protection was provided for the receiver and other electronic components. Hence, it was possible to easily damage these components. Finally, except for the tendency of the material to return to its initial shape, the memory of the molded housing, the housing, which was relatively thick, incorporated no force applying structure which tended to force it outward when inserted in the ear canal to provide a feedback reducing seal with the canal.
There continues to be a need for more comfortable hearing aids. Since ear canals are known to change shape and volume in response to jaw movement, it would be preferable if such changes could be responded to dynamically. In addition to comfort, there continues to be a need for hearing aids which effectively seal with the respective ear canal. It would be desirable to provide such improved functionality in either custom or standard sizes of hearing aids.

This patent is subject to a terminal disclaimer.


A light emitting device is provided which contains an anode, a cathode, and two organic layers disposed between the anode and the cathode. The first organic layer contains a phosphorescent material and the second organic layer contains a crosslinked body of a crosslinkable material and a phosphorescent material. The two phosphorescent materials contain the same phosphorescent compound represented by formula (1), and the crosslinkable material is a compound represented by formula (3):

Light emitting devices such as an organic electroluminescent device (organic EL device) can be suitably used for display and illumination because of properties such as high light emission efficiency and driving at low voltage, and are drawing attention in recent years. This light emitting device comprises organic layers such as a light emitting layer and a charge transporting layer.
Patent document 1 discloses a light emitting device comprising a first organic layer comprising a phosphorescent compound (B), (G) or (R) represented by the following formula and a second organic layer composed only of a crosslinked body of a crosslinkable material XL represented by the following formula.
(Chemical Formula 1)
Crosslinkable Material XL

Abstract: In formula (1), M represents a metal atom, n1 is ≥1, n2 is ≥0, E1 and E2 represent a carbon atom, L1 and L2 represent an aromatic heterocyclic ring, and A1-G1-A2 represents an anionic bidentate ligand.

Abstract: In formula (3), mB1 to mB3 represent an integer of ≥0, Ar7 may represent an aromatic hydrocarbon group, LB1 may represent a divalent group, and X″ may represent a crosslinkable group.


A method of obtaining a series of images of a three-dimensional object by transmitting pulsed terahertz (THz) radiation through the entire object from a plurality of angles, optically detecting changes in the transmitted THz radiation using pulsed laser radiation, and constructing a plurality of imaged slices of the three-dimensional object using the detected changes in the transmitted THz radiation. The THz radiation is transmitted through the object as a scanning spot. The object is placed within the Rayleigh range of the focused THz beam and a focusing system is used to transfer the imaging plane from adjacent the object to a desired distance away from the object. A related system is also disclosed.

The term "terahertz" (THz), originally used by sub-millimeter spectroscopists to describe spectral lines with frequencies in the trillions of hertz, today is applied to broadband pulsed electromagnetic (EM) radiation between the infrared and microwave bands of the EM spectrum, ranging from 0.1 to 10 THz. The photon energies of THz radiation range from 0.4 to 80 mev, which corresponds to the range of fundamental energies associated with changes between molecular energy levels.
Over the past 20 years the technologies in the THz field have developed significantly, both in the generation of THz radiation as well as in its detection. Recent advances in high-speed optoelectronic and femtosecond laser technology facilitate generation and detection of short bursts of terahertz radiation, which has proven to be extremely useful for spectroscopic measurements in the sub-millimeter-wave range. Terahertz imaging combines these coherent spectroscopic measurements with real-time imaging and advanced signal processing and recognition, so that each pixel element of the image contains spectroscopic information about the object. Terahertz radiation is described in greater detail in an article by M. Nuss entitled "Chemistry is Right for T-Ray Imaging," Circuits & Devices, IEEE (March, 1996).
Typical apparatus and associated imaging methods for free-space electro-optic characterization of propagating terahertz beams are described in U.S. Pat. No. 5,952,818 issued on Sep. 14, 1999 to Zhang et al. and assigned to the assignee of the present invention, Rensselaer Polytechnic Institute. The sensing technique is based on a non-linear coupling between a low-frequency electric field (terahertz pulse) and a laser beam (optical pulse) in an electro-optic crystal, such as a zinc telluride (ZnTe) crystal. Modulating the crystal's birefringence by applying the polarized electric field to the crystal modulates the polarization states of an optical probe beam passing through the crystal. This ellipticity modulation of the optical beam is then polarization-analyzed to provide information on both the amplitude and phase of the applied electric field.
A further improvement in terahertz imaging is disclosed in U.S. Pat. No. 6,414,473 issued on Jul. 2, 2002 to Zhang et al. and also assigned to Rensselaer Polytechnic Institute. The described imaging system in this reference employs a chirped optical beam and dynamic subtraction to rapidly reconstruct an image, thereby providing a system that is suitable for real-time imaging applications. According to this patent, the imaging system generates a free-space electromagnetic radiation pulse positionable to pass through the object to be imaged. One of an electro-optic crystal or a magneto-optic crystal is positioned so that the electromagnetic radiation pulse passes through the crystal after passing through the object.
The system further generates a chirped optical probe signal to impinge the crystal simultaneously with the electromagnetic radiation pulse passing through the crystal so that a temporal waveform of the radiation is encoded onto a wavelength spectrum of the chirped optical probe signal. The chirped optical probe signal modulated by the free-space radiation is then passed to a decoder for decoding a characteristic of the free-space electromagnetic radiation using the chirped optical probe signal with the temporal waveform of the radiation encoded on the signal. The system further determines a characteristic of the object using the characterization of the free-space electromagnetic radiation pulse after passing through the object.
Both of the patents summarized above are incorporated, in their entirety, in this document by reference.
Tomography refers to the cross-sectional imaging of an object from measuring either the transmitted or reflected illumination. Three-dimensional THz tomography coupled with spectroscopic analysis has many potential applications such as mail package examination, security screening, and nondestructive inspection. In 1997, Mittleman et al. demonstrated THz tomography in which the 3D image of a floppy disk was successfully reconstructed using reflected THz pulses and a digital processing algorithm. A number of assumptions were made in the use of the algorithm: first that the targets had no dispersion and diffraction, second that the reflection is so weak that multiple reflections could be ignored, and third that the refractive index is uniform in each layer examined. Such assumptions restrict the applicability of the tomographic technique and exclude the possibility of spectroscopic analysis.
Although computed tomography is well known in X-ray radiographic imaging, a serious problem in reconstructing an image using THz computed tomography is that the THz wave does not satisfy the short wave limit as the X-ray satisfies in X-ray computed tomography. For example, if one attempts to image a 10 cm target using a THz beam with a 10 cm Rayleigh range, the minimum THz beam size will have an electric field waist of 6 mm. Therefore, if one treats the beam as a ray line, the resolution will not be any better than 6 mm. This implies that the resulting image of the target only contains 30×30 pixels—an inadequate resolution. Therefore, a need remains for a THZ CT imaging system and imaging method that provide improved resolution compared with the resolution obtained using traditional X-ray computed tomography technology and that permit the use of the computed tomographic algorithm.

Transmission mode terahertz computed tomography


A system and method for controlling the position of a digital data storage device slider through the use of an electro-thermal micromechanical actuator is disclosed. A movable member is etched into a face of a slider opposite the air-bearing surface of the slider. The movable member is substantially freestanding in relation to the slider, having only a single end connected to the slider. An electrically actuated heater element with two parallel current paths is disposed on the movable member. One of the current paths is substantially narrower than the other current path. When a current is passed through the heater element, the narrower current path heats up more quickly than the wider current path. By varying the current passed through the heater element in a selected manner, a distortion of the movable member is harnessed and used to create a relative motion in the slider body, allowing the slider to be quickly and exactly located over the centerline of a track of a storage device.

1. The Field of the Invention
The invention relates to digital storage devices having a rotating media and more specifically to systems and methods for finitely positioning a read/write slider in such a storage device.
2. The Relevant Art
Computer systems generally utilize auxiliary storage devices onto which data can be written and from which data can be read for later use. A direct access storage device (DASD) is a common auxiliary storage device in which data is stored in known locations and accessed by reference to those locations. A hard disk drive is a type of DASD that incorporates rotating magnetic disks for storing data in magnetic form on concentric, radially spaced tracks on the disk surfaces. Transducer heads driven in a path generally perpendicular to the drive axis are used to write data to and read data from addressed locations on the disks. These transducer heads are often referred to as sliders.
Current hard disk drives also typically utilize an actuator connected to the slider by a support arm assembly. The actuator moves the slider to the desired track and maintains it over the track centerline during read or write operations. The movement of the slider to a desired track is referred to as data seeking or merely "seeking," Maintaining the slider over the centerline of the desired track during read or write operation is referred to as track following or "tracking."
Current hard disk drives also typically utilize an actuator connected to the slider by a support arm assembly. The actuator moves the slider to the desired track and maintains it over the track centerline during read or write operations. The movement of the slider to a desired track is referred to as data seeking or merely "seeking." Maintaining the slider over the centerline of the desired track during read or write operation is referred to as track following or "tracking."
The voice coil motor (VCM) typically comprises a coil movable throughout the magnetic field of a permanent magnetic stator. The application of current to the VCM causes the coil, and thus the attached head, to move in a radial fashion. In the absence of bias forces, the acceleration of the coil is proportional to the applied current. A power amplifier in response to a control input supplies this current.
In modem hard disk drive systems, the density of data tracks on the magnetic disks is increasing at a dramatic rate. Prior art control systems of the described type are experiencing difficulty in adequately positioning the slider exactly over the centerline of the track for read and write operation in such high density hard disk drives. As the track pitch of hard disk drives becomes smaller, prior art VCM systems are becoming inadequate at positioning the slider with sufficient speed and accuracy to ensure that the read/write transducer remains positioned over the centerline of the desired track during read and write processes.
Accordingly, it should be apparent that a need exists for an improved positioning device capable of finely positioning the slider of a hard disk drive such that a read/write transducer can be quickly and accurately positioned over the centerline of a DASD track in response to control signals from the DASD and positioning signals from the disk surface of the hard disk drive.

Electro-thermal micromechanical actuator for finitely positioning a storage device slider and methods of use and manufacture


A system is provided in an exhaust emission sampling system for controlling a flow controller in order to compensate for the effects of changing water vapor content in a diluted sample having a predetermined dilution ratio. A water measuring device such as a relative humidity sensor generates a water vapor signal based on the amount of water vapor in the diluted sample. The water vapor signal is then processed within a control unit to obtain a value for the amount of water in the diluted sample. A control signal is generated by the control unit based on the amount of water vapor, flow rate of the exhaust emissions, and also, on the type of fuel used in the combustion process to control the flow controller which is, preferably, a mass flow controller. A second system is provided in an exhaust emission analyzing system for determining a final amount of pollutants also compensated for the effects of changing water vapor content in the exhaust emissions. The control unit not only processes the water vapor signal from the sensor to obtain a value for the amount of water vapor in the diluted sample as in the first embodiment, but also generates a correction factor based on the value. The correction factor is then utilized by a computer to calculate a final amount of the pollutants based on the correction factor and a preliminary amount of pollutants determined by analyzers of the exhaust emission analyzing system.

The constant volume sampler (i.e. CVS) was first applied in the late 1950's to make possible the measurement of the mass of exhaust emissions. Before that time, emissions tests had been based on concentration limits. Since the effect on the environment is assessed by the grams of pollutants emitted by vehicles per mile driven, a sampling system was needed that could measure the mass of these emissions while the vehicle was operated through a sequence of accelerations and decelerations that approximated normal driving.
The CVS and its operation are illustrated in FIG. 1 wherein vehicle exhaust enters the CVS at inlet 10, ambient air for dilution enters at 12, and ambient bags and sample bags are indicated at 14 and 16, respectively. The CVS also includes a sample flow pump and a controller 18, a measuring device 20 such as a CFV or SAO to measure CVS flow to calculate volume, and a blower or pump 22 to set CVS flow rate.
All of the vehicle's exhaust is diluted with ambient air in the relatively large mixing "T" of FIG. 1. The combined gases are drawn through the system by the blower or pump 22 at a relatively constant combined flow rate. Thus, a CVS operates at a variable dilution ratio. As the vehicle produces more exhaust, less ambient air is mixed with it in order to keep the total flow constant.
The measuring or metering device 20 in the bulk stream determines the flow rate. In this manner, the total volume of the mixture is easy to determine from the time of the sampling multiplied by the constant flow rate. Today, CVS units actually do not quite operate at a constant rate of flow, but the name CVS is still used.
A small, proportional sample of the diluted gases is collected in the sample bags 16 during the sampling period. The sample bags 16 are analyzed later for the concentrations of the pollutants. A simultaneous sample of the dilution air is also collected in the bag 14 for subsequent analysis.
There are several types of CVS units available today, including fixed flow PDP and CFV types as well as variable flow SAO types.
The requirements of testing low emission vehicles make better sampling systems necessary. Vehicles today may use alternative fuels such as Methanol, CNG and LPG. Burning these fuels produces more water, requiring more dilution, which lowers sample concentrations.
However, the same vehicles are likely to be LEVs and ULEVs, low and ultra low emission vehicles. The emissions from these vehicles are very low, and the concentrations have become very difficult to measure accurately. It is clearly important not to over-dilute these samples, making them even more difficult to measure.
To meet these conflicting requirements, a CVS needs to operate at the correct flow rate for each vehicle, fuel and ambient condition. CVS units based on fixed flow metering orifices however, are only able to operate at a relatively small number of fixed flow rates.
At this point, the CVS method is very near its limit of capability for accurate measurement of low amounts of pollution. The basic limitation arises from the method for diluting the exhaust gases. The only diluent available in sufficient quantity to be practical in a CVS is the ambient air in the test cell. However, this gas already contains considerable water and has background concentrations of the pollutants that can be as large as the concentrations coming from the vehicle. So the CVS must dilute the exhaust gases more than necessary with contaminated diluent. The sample concentrations that result are too low to be conveniently analyzed with conventional gas analyzers and the need to compensate for an almost equal amount of pollutant contributed by the background doubles the uncertainty of the measurement.
Mini-diluters are a new class of devices that avoid these limitations by reversing the order of the diluting and sampling of the exhaust gases, as shown in FIG. 2. The mini-diluter of FIG. 2 includes a pump 24 and sample bags 26.
As previously mentioned, while a CVS system must dilute all of the vehicle's exhaust at a variable dilution ratio, and then take a proportional sample, a mini-diluter reverses this process by first taking a small sample of the exhaust gas and then accurately diluting it at a relatively constant dilution ratio. Since only a small volume of diluent is needed, a dry, contaminant free gas, dry air or nitrogen, can be used. Two advantages are the higher, more easily measured concentrations resulting from less dilution and the absence of background contaminants, eliminating a need for a separate, error prone analysis of the background pollution. The collection and analysis of samples of the diluent air is eliminated, doubling the accuracy of the mass calculation.
A challenge for the mini-diluter is that the rate of collected sample over a test period must be kept proportional to the raw exhaust flow from the vehicle, which is strongly varying, instead of the bulk stream flow through the CVS, which is relatively constant.
The following table illustrates the improvement in accuracy that can be expected with a mini-diluter. It shows the expected sample bag concentrations for a vehicle getting 25 mpg tested at 50% relative humidity at 74.degree. F. that meets the required ULEV emissions levels. The table compares the resulting bag concentrations for a standard CVS with fixed flow at 320 cfm, as referenced in the Code of Federal Regulations, a variable flow CVS, optimized for these conditions, and for a mini-diluter.
______________________________________ Expected Bag Concentrations ULEV Limit CVS VFCVS Mini-Diluter ______________________________________ HC 0.040 g/mi 1.1 ppm 1.9 ppm 3.3 ppm CO 1.70 g/mi 22.7 ppm 39.1 ppm 70.1 ppm NO.sub.x 0.20 g/mi 1.6 ppm 2.8 ppm 5.0 ppm ______________________________________
It can be observed that the mini-diluter technique raises the bag concentrations enough that it is feasible to measure these levels with the same analyzer technology that is in use today.
All these sampling systems, fixed and variable flow CVS's as well as mini-diluter, must perform the following three functions:
Prevent condensation of water in the sample before it can be measured. The water content creates two problems. First, water condensing during the analysis process changes the concentration or the volume of the sampled gases, affecting the accuracy of the result. Second, some contaminants, such as formaldehyde and NO.sub.x, are affected by the removal of water. PA1 Measure the total gas volume over a sampling interval, so the mass of emissions can be calculated. PA1 Collect a proportional sample of diluted exhaust in a sample bag for analysis. At any time, the rate of flow of sampled gases and the total rate of flow of diluted exhaust through the CVS must be in the same proportion.
An improved mini-diluter of the above-noted patent application is illustrated in FIG. 3. The mini-diluter of FIG. 3 includes critical flow orifices (CFO's) 28 to establish a stable dilution ratio. One of the orifices 28 is for the diluent, either nitrogen or dry air, and the other of the orifices 28 is smaller and is for the sample gas. The orifices 28 operate on the principle from fluid dynamics that the flow through an orifice reaches a known maximum flow when the pressure drop across it is large enough that the velocity in the orifice throat reaches the speed of sound. The two orifices 28 are appropriately sized to provide a fixed dilution ratio appropriate for the type of fuel being used.
A modified pressure regulator 30 of the mini-diluter maintains equal pressure at the inlets of the two orifices 28, even as the conditions at the sampling point may change. A reference port is connected to the sample inlet and the action of the regulator 30 keeps the pressure at the inlet of the diluent orifice equal to the pressure at the inlet to the sample orifice.
The wet raw gases are brought to the dilution component via heated lines, and the orifices 28 and pressure regulator 30 are kept in an oven 32 to prevent any condensation of the sample before it is diluted. The oven 32 also keeps the inlet temperatures of both orifices 28 at the same temperature. Together with the action of the pressure regulator 30, this keeps the dilution ratio relatively constant.
The diluted gases can then be pumped by a pump 34 and then routed to either a conventional analyzer bench 36 for a modal analysis or sent to sample bags 38. When used for modal sampling, the mini-diluter replaces the usual sample conditioning unit, providing the advantages of much less extracted sample and no modification of the sample by a cooler.
A mass flow controller 40 having a control valve (not shown) is used to proportion the flow to the bags 38. The absolute accuracy of the mass flow controller 40 is not critical, only that its flow be kept in proportion to the vehicle exhaust flow. It is also important to compensate for the gas transport delays from the sample point to the flow controller 40 so that the desired weighting of the collected gases is correct.
As noted above, one approach to implementing a mini-diluter has been to use mass flow controllers, such as commonly used in the semiconductor industry, to control the rates of flow of raw exhaust sample, diluent gas and proportional diluted sample. However, early attempts have not yet been entirely successfully demonstrated to be equivalent to the CVS method. The stability of the mass flow controllers and the sensitivity of their controlled flow rate to the composition of the flowing gases, as well as their slower response times to sudden changes in desired flow, have presented difficulties.
One of the difficulties of sampling exhaust, which others may not fully appreciate, is the changing water content of the sample. A key realization is that water is lost from the exhaust gas even inside the vehicle exhaust manifolds and piping, before it is even available to be sampled, even by a mini-diluter using heated sampling lines. An engine is initially cold when testing begins and it is during this relatively brief period that most of the pollutants are emitted. It is also during this period that the inaccuracies caused by lost water vapor from condensation in the exhaust manifolds and tailpipes have their greatest influence on the performance of the active elements of the mini-diluter.
The critical flow orifices 28 of FIG. 3 are affected by the changing water content of the exhaust gases, but to a much lesser extent than are the thermo-dynamic elements of a mass flow controller. The mass flow controller 40 of FIG. 3 is utilized only to proportion the sample to the exhaust flow. The absolute accuracy of the flow is not important, since this flow does not need to be measured.

System for controlling flow of a diluted sample and determining pollutants based on water content in engine exhaust emissions


A ribbon-shaped ion beam having an elongate cross-section normal to a beam direction is modified by generating, at a predetermined position along the ribbon-shaped beam, a magnetic field extending in an x-direction along an x-axis. The x-direction magnetic field has a non-uniform intensity which is a desired function of x.

1. Field of the Invention
This invention relates to ion implantation and in particular to a method of modifying a ribbon-shaped ion beam which has an elongate cross-section normal to a beam direction, and also to apparatus for modifying such a ribbon-shaped ion beam.
2. Background Information
Ribbon-shaped ion beams are known to be used for implanting ions into substrates, particularly semiconductor substrates as used in the semiconductor manufacturing industry. Typically, such semiconductor substrates comprise relatively thin wafers of the substrate, commonly formed of monocrystalline silicon. Wafers of monocrystalline silicon may be circular with a diameter of about 200 or about 300 mm, although other shapes and dimensions may be used. A ribbon-shaped ion beam can be used for implanting ions into such wafers, in which case the ribbon-shaped ion beam may be controlled to have an elongate cross-section at the location of the wafer to be implanted which has a length just greater than the diameter of the wafer. Then, in order to ensure an even implantation of ions over the entire surface of the wafer, it may be necessary only to produce relative movement between the ribbon-shaped ion beam and the wafer in a direction perpendicular to the elongate cross-section direction of the ion beam.
It is a known requirement in the field of ion implantation into semiconductor substrates, that the dose of ions being implanted should be delivered evenly over the entire surface of the wafer. To achieve this, it is therefore important that the ribbon-shaped ion beam has an even distribution of intensity over the width of the elongate cross-section of the ion beam at the location of the wafer being implanted. Intensity non-uniformity over the elongate cross-section of the ribbon beam can be caused at the ion source, through a number of processes, including errors in the alignment of extraction electrodes, temperature effects, and physical changes causing plasma non-uniformity within the ion source chamber. It is therefore become a common practice in the production of ribbon-shaped beams for ion implantation, to employ a beam line profilometer, which can measure intensity variations across the ribbon beam, in combination with some suitable uniformity correction apparatus.
A known apparatus for modifying a ribbon-shaped ion beam has a high magnetic permeability rectangular steel structure defining an elongate open space which accommodates the ribbon-shaped beam passing through the rectangular structure with the length of the elongate open space aligned with the long cross-section of the ribbon beam. Multiple individual coils are distributed along each of the long bars of the rectangular steel structure, with individual controllable power supplies establishing current through each of the coils. These multiple coils may be energized to produce selected field distributions in the open space within the rectangular steel structure, including quadrupole, other multipole field distributions and other useful magnetic field distributions.
It is also known to employ quadrupole and other multipole field distributions in the field of magnetic spectography, for correcting aberrations in the trajectories of particles travelling through a spectrograph. The technical considerations for magnetic spectrographs are, however, very different compared to those applicable for a ribbon-shaped beam used in an ion implanter. Most particularly, space charge considerations are normally completely absent in magnetic spectrograph applications, as there is seldom more than a single charged particle traversing any region of a spectrograph at any time. In general, the considerations relating to the correction of optical aberrations along the charged particle path of a magnetic spectrograph are quite different from the considerations mentioned above for modifying, and improving the uniformity, of a ribbon-shaped ion beam in the ion implantation of semiconductor substrates.

Method and apparatus for modifying a ribbon-shaped ion beam


A latch (10) including a casing (12) adapted to be fixedly mounted in a door, a carriage (20) mounted in the casing (12) and adapted for slidable movement relative to the casing (12) between an actuated position and a return position, a first spring (34) biasing the carriage (20) to the return position and a lock bolt (42) mounted to the carriage (20) and adapted to protrude from the casing (12) when the carriage (20) is in the return position. The latch (10) also includes a master cam (60) and a slave cam (80) each pivotally mounted to the casing (12) such that the master cam (60) directly acts upon the slave cam (80) whereby the pivoting actuation of the master cam (60) drives pivoting actuation of the slave cam (80) which in turn actuates sliding movement of the carriage (20) from the return position to the actuated position. Pivoting actuation of the master cam (60) through at most 35° is sufficient to move the carriage (20) to the actuated position.

The use of latches to retain doors closed but not locked is widespread, particularly for internal doors of residences or offices where locking security is not required. Latches have a lock bolt that is spring-biased to a latching position, in which the lock bolt protrudes from an edge face of the door. Turning a knob or lever associated with the latch retracts the lock bolt to its unlatching position in which the lock bolt is retracted into the door, to allow the door to be opened. The knob or lever is also spring-biased to a position corresponding to the latching position of the lock bolt. This is typically horizontal for a lever handle.
When the door is closed without turning a knob or lever, the lock bolt initially engages a strike plate attached to a door jamb which urges the lock bolt to retract into the door, into the unlatching position. The lock bolt then travels across the strike plate and enters a recess in the strike plate. This allows the lock bolt to return to its (protruding) latching position to retain the door closed.
A known simple latch uses a single spring to bias the latch mechanism and the knob or lever to the latching position. A spring of sufficiently high stiffness to return the knob or lever to the latching position often makes it difficult to close the door without also turning the knob or lever, which is inconvenient. A spring of sufficiently low stiffness to allow easy door closure without turning of the knob or lever often does not return the latch mechanism and the knob or lever to the latching position (which can result in lever sag) and so won't reliably latch the door.
Another known latch uses a single spring for biasing the lock bolt and a separate return mechanism in the door furniture to return the knob or lever to the latching position. This complicates the production and assembly of the latch.
Another known latch utilises a relatively stronger spring to return the knob or lever to prevent sag and a relatively weaker spring to bias the lock bolt to provide easy door closure. A disadvantage of known latches of this type is that they require the knob or lever to be rotated through at least 75° to sufficiently retract the bolt for door opening.
Other known latches require that components of the latch mechanism protrude significantly outside of the latch casing. A disadvantage of known latches of this type is that they requires a large cross bore hole in the door to accommodate the protruding components and equally large door furniture to conceal the bore hole.
It is the object of the present invention to substantially overcome or at least ameliorate one or more of the above prior art disadvantages.

Gainsborough Hardware Industries, Limited


A method of manufacturing a cable assembly using stranded cable material. A manufacturing jacket is placed over the cable to hold the strands in a desired state. A length of jacketed cable is then cut to a desired length. Appropriate terminations are slipped over the manufacturing jacket on the cable's first end, its second end, or at some intermediate point. For a typical type of termination, a short portion of the manufacturing jacket is stripped away at the point of termination to expose the strands. After the terminations are placed in the appropriate position, potting compound or other mechanical means are typically applied to lock the terminations to the exposed lengths of strands. A completed cable assembly is thus created. However, the presence of the manufacturing jacket, while highly desirable for manufacturing, is often undesirable for end use. All of the manufacturing jacket, or in some instances a substantial portion thereof, is therefore removed, using a variety of disclosed methods, to form an unjacketed cable. A variety of techniques are disclosed for carrying out these steps, including the use of modified terminations and modified jackets. The finished product may have no jacket at all, a partial jacket, or a jacket which is different from the one used in the manufacturing process.

1. Field of the Invention
This invention relates to the field of cables. More specifically, the invention comprises a manufacturing method which allows the automation of previously manual processes, as well as providing a superior end product.
2. Description of the Related Art
Ropes and cables have been traditionally made of natural fibers or metals. These would include wire rope and hemp "hawsers." In the last half century, synthetic fibers such as NYLON and polyester have been commonly used to replace natural fibers. NYLON and polyester ropes have been used for low tension applications, whereas wire ropes (typically steel) have been used for high tension applications.
Those skilled in the art will know that wire rope behaves very differently from NYLON or polyester rope. Though it is stronger for a given cross section, it is also very stiff. If a wire rope is kinked, the constituent strands may undergo plastic deformation—permanently damaging the rope. Thus, wire ropes must be fed around large radius pulleys, pins, or capstans and must otherwise be protected from kinking. Those skilled in the art will also know that wire rope is susceptible to corrosion, typically rusting, as well as fatigue. It is also quite heavy. Thus, there has long been the desire to obtain the high-strength properties of wire rope without its inherent stiffness and weight.
In recent years, progress has been made in this regard. Advanced synthetic fibers have come onto the market in addition to the older synthetic fibers. These fibers include KEVLAR, VECTRAN, ZYLON, and SPECTRA, to name a few. These advanced synthetic fibers typically have smaller diameters for the individual fibers that was common for the older materials—though this is not always the case.
FIG. 1 shows a stranded cable 10. It includes a stranded core 14, composed of a cluster of parallel strands. Surrounding stranded core 14 is braided strand jacket 12. Although the individual strands are depicted as being substantial in size, the reader should appreciate that they are often very small—having the diameter of a human hair or even less. Within the cabling industry, the individual constituents within a bundled cable are called "fibers" or "strands." Some publications use "strands" for metal constituents and "fibers" for non-metallic constituents. Throughout this disclosure, the term "strands" will be used to describe both metallic and non-metallic constituents.
Braided strand jacket 12 is used, among other purposes, to contain the parallel strands within strand core 14. In its absence, stranded core 14 can become disorganized. Those skilled in the art will know that the style of weave shown in FIG. 1 is one of dozens in common use. In some cases, the entire cross section of a cable is formed by sets of helical wrappings as shown for braided strand jacket 12.
In order to be useful, any cable must be terminated. That is, any cable must have attachments provided on its two ends (or sometimes at one or more intermediate points) to transmit a tensile load. In the simplest form, these terminations can simply be tying the cable to attachment cleats by knotting or looping. In order to maximize the strength of the completed assembly, however, more efficient terminations are desirable. Such terminations can also facilitate connection of the cable via threads, grommets, eyes, snapping features, etc.
FIG. 2 shows one type of termination. Anchor 16 has been affixed to the end of stranded cable 10. Anchor 16 incorporates loading flange 20. In operation, anchor 16 would be passed into a grommet, so that loading flange 20 can bear against a mating surface and place tension on the cable. Numerous other types of terminations are known, including hooks, threaded fasteners, eye fittings, button studs, clevis fittings, etc.
FIG. 3 shows stranded cable 10 from the top and from the side, with the side view having a partial section to reveal the internal details of this particular type of termination. The reader will observe that tapered bore 18 passes completely through anchor 16. One method of locking the termination in place is as follows: Strands 22 of stranded cable 10 are splayed within tapered bore 18. Potting compound 24—typically high strength resin—is then poured into tapered bore 18. Once potting compound 24 solidifies, strands 22 are locked within tapered bore 18.
Of course, potting is not the only method used to affix terminations. The present invention applies to both potted and non-potted terminations. Other methods of affixing terminations include compression fittings and mechanically swaged fittings. However, as potting is a quite common method, most of the examples are presented for use with the potting approach.
Potting is carried out in a variety of ways. Where the use of very fine strands makes wetting difficult, it may be desirable to wet the strands while they are exposed and loose. Anchor 16 is then pulled over the wet strands. The liquid potting compound is then allowed to harden. Whatever potting method is used, the result after hardening is shown in FIG. 3. Loading flange 20 may then be used to put tension on stranded cable 10 without pulling the strands free of anchor 16. FIG. 4 shows the result with anchor 16 removed for visual clarity. The tapered shape of potted region 32 locks it in place. Although a conical shape for tapered bore 18 has been illustrated, many different shapes can be used, so long as they generally expand from left to right in the view as shown, or have ribs or other features which will mechanically engage the potted strands.
Those skilled in the art will know that the alignment of the strands in the finished termination is important to the ultimate strength, stiffness, fatigue resistance, and working life of the stranded cable. The typical goal is to maximize the maximum allowable stress of the completed assembly as a percentage of the maximum allowable stress of one of the individual strands (In other words, the load should be evenly distributed among the strands).
One factor influencing the result is the nature of the transition from the freely flexing portion of the cable to the region locked within a termination (In this case—potted region 32). FIG. 5 shows this transition as termination plane 34. Termination plane 34 is ideally perfectly orthogonal to the central axis of stranded cable 10, meaning that the anchor attached is perfectly parallel to the central axis of stranded cable 10.
Prior art techniques for creating a terminated cable often manage to generally align the termination with the bundle of strands. However, because the strands are free to shift around, it is often true that some strands have more slack along their length than others. Once the terminations are attached, the result is that some strands within the stranded cable are slightly longer then others. When the cable is loaded in tension, the load will be initially transferred to the shortest strands. The shorter strands can overload and break. This causes a cascading failure as the load is carried by fewer and fewer strands. Thus, the load-carrying ability of the stranded cable will be compromised.
The individual strands within stranded cable 10 are also often difficult to process. Although they can be cut using a metal blade, many strands are not cut easily (NYLON and polyester being notable exceptions). The cable as a whole will tend to smash flat or flare out under the cutting knife and deform. Thus, traditional cutting methods may produce varied results. Cutting and terminating processes on stranded cables are also made difficult by the following additional factors:
1. The strands along the length of the cable can easily shift or snag during production processes, thereby causing misalignments;
2. The accurate positioning and application of a temporary localized binding mechanism (such as tape or bundling string) is difficult (explained in more detail subsequently). The length between the binding mechanism and the end of the cable is critical for properly creating the termination. Thus, the inability to accurately position the binding mechanism introduces error;
3. The addition of a localized binding mechanism causes an increased overall diameter, which may snag on machinery, feed holes, terminations, or the like;
4. A temporary localized binding mechanism is generally unable to bind the strands tightly. It is also difficult to maintain a predictable outer diameter. This fact means that bores through the terminations must be oversized. The result is a sloppy fit between the termination and the strands;
5. The individual strands are so small that they tend to wedge between opposing cutter knives rather than shearing;
6. The stranded cable often has little stiffness in compression, meaning that it cannot be reliably fed into a hole, holding device, or termination by pushing;
7. When a stranded cable is cut, many strands on the outside will fray and catch on moving equipment, feeding devices, terminations, feed holes, and the like;
8. The strands themselves are often very slick, making it difficult to control movement and to accurately measure length (because of slippage in the measurement device);
9. The stranded cable tends to flatten when passed around drive capstans and similar hardware, meaning that a constant diameter is not maintained; and
10. In order to cut the stranded cable to a consistent length, it is commonly placed under tension. When the cut occurs, a "snap back" can result. And, of course, not all the strands are cut in the same instant. When the first are cut, these snap back and the load on the remaining strands increases. Since tension is maintained approximately constant for the stranded cable as a whole, the remaining strands elongate before they are cut. The result is that the strands have different lengths, and may be displaced.
FIG. 6 shows one approach to the problem of cutting a stranded cable. Stranded cable 10 is wrapped with tape 28 (a form of localized binding mechanism) at the point where it is to be cut. Tape wrap 26 binds the cable and keeps the strands somewhat aligned. The alignment function is restricted, however, as the tape only holds the strands in the position they occupied just prior to its application. The strands may have become quite misaligned by this point, through handling and spooling of the stranded cable. Even a small bend in the cable can produce significant misalignment.
FIG. 7 shows knife 30 cutting stranded cable 10. Such a shearing action is appropriate in some circumstances. An angled guillotine type blade is also commonly used. FIG. 8 shows a possible result: Sheared surface 36 is not perpendicular to the central axis of stranded cable 10. In addition, the reader will observe that the round cross section has been deformed into an oval at sheared surface 36.
A thorough and tight taping job can minimize these deformations. With manual skill, a technician can in fact produce a perpendicular cut without substantially deforming the stranded cable. However, despite these efforts, the cable may still contain strands having unequal overall lengths. The strands may also be misaligned. Although sheared surface 36 may tend to "relax" into a more perpendicular and round shape, the discrepancies in strand length will remain. The repeatability of such manual processes is limited. Thus, it is difficult to predict the ultimate physical strengths and other properties of a cable manufactured using these prior art techniques.
In order to complete the termination process, additional steps must be performed. A termination is slipped over the tape and slid down the cable a short distance. The tape is then removed to expose the end strands. A second taping is applied at the position where the strands enter the termination. The exposed end strands are then potted into the termination.
The taping and re-taping process is obviously labor intensive. It also requires a skilled employee. FIG. 9 shows a resulting termination in cross section. The bore through the termination must be made oversized to allow for the inconsistent diameter, fiber misalignment, and lack of concentricity of the taped cable. The reader will observe that anchor 16 is not properly aligned with the centerline of the stranded cable. The assembly in FIG. 9 is obviously an undesirable result. The shortcomings of the taping example presented are also true when using other manual binding processes.


A power system for an electrical system with highly fluctuating loads is powered by one or more power sources that are slow to react to load changes. The power sources are connected to electrical equipment used on the drill rig which provide active load to the generators. One or more load banks may be positioned to provide passive load to the generators to maintain generally constant generator load, while allowing for instant access to power as active load increases. Generators may be run at 100% capacity, a maximum efficient capacity, or at a high enough level to allow for a sufficiently rapid increase in power output. At least one parameter of a drilling operation may be utilized to anticipate load demand changes.

In a modern drilling rig, much of the associated equipment is driven electrically. For some drilling rigs, generators are used to supply electricity to the drilling rig. In general, generators are most efficient when producing power within a certain range of power output. During drilling operations, electric loads may vary greatly depending on what is happening at the rig at any given time. Electrical equipment, including drawworks, mud pumps, top drives, rotary tables, etc. may consume large amounts of power when in use. Because each piece of equipment is used intermittently, the power drawn by the drilling rig may vary greatly at different times, at times going from very high to very low in short intervals. At other times, very little power is consumed by the drilling rig equipment. Additionally, a rapid decrease in electric load may cause a power spike which may cause the rig and generator to automatically shut down.


The circuit is for the measurement of the current of the memory cells of an electrically modifiable non-volatile memory. The read circuit is complemented by two current sources to improve the biasing of the current mirror of the read circuit during the measurement.

The methods used to manufacture integrated circuits very often introduce defects. Thus, after manufacture, each integrated circuit is subjected to tests aimed at detecting the presence of such defects. In the case of non-volatile memories, it is ascertained first of all that the column and row decoders of the memory are working properly by programming cells of the memory array in predetermined configurations, and then carrying out successive readings of these same cells. Any divergence between the data elements that should have been written and the data elements read indicates the presence of a defect.
The leakage current of these memory cells is then measured, and, thus, it is ascertained that the value of this leakage current is acceptable or not acceptable. The source of these leakage currents is varied: it may be the presence of electrical charges in the oxide layer of the transistor of the memory cell or a defect in the structure of the memory cell that, for example, generates a leakage current.
At the present time, this measurement of leakage current is an analog measurement done by means of a testing apparatus whose inputs are connected to the external terminals of the memory to be tested. In practice, a cell to be tested is selected by the application to its grid of a zero voltage, and the current flowing in the bit line connected to this cell is measured. The leakage current is then accessible on the data pad associated with the cell, care being taken to short-circuit the read circuit connected to the bit line concerned. The value of the leakage current measured is then compared with a current threshold value indicating whether the cell is defective or not. Typically, the maximum leakage current acceptable for a cell is in the range of 10 microamperes for a reference current in the range of 50 to 100 microamperes. The testing apparatus is generally a programmed unit designed to generate the addresses of the memory cells of the matrix one-by-one, and measure the leakage current flowing in the corresponding bit line for each of the memory cells.
The main drawback of this measurement of the leakage current lies in its relatively lengthy performance time, for it is an analog measurement. The use of equipment external to the memory is another drawback for it is liable to introduce unwanted currents, and, hence, falsify the measurement of the leakage current.
One approach to address these drawbacks includes using the read circuit of the memory to perform this measurement. Usually, the read circuit of a non-volatile memory is entrusted with the task of comparing the current flowing through a memory cell with a reference current during a reading phase. During the reading phase a read voltage is applied to the grid of the memory cell to be read. The read circuit then delivers a logic data element indicating whether the current of the cell is smaller than or greater than the reference current which, for its part, is set by a reference cell.
To measure the leakage current of a memory cell, it would be enough to apply a zero voltage to the grid of the memory cell to be tested and then compare the leakage current with a reference current equal to a predetermined maximum leakage current. However, this technique, which could very easily be implemented in standard memories, is not very precise. Indeed, when the reference current is very low, in the range of some microamperes, the low value of the reference current can no longer be used for the accurate biasing of the current mirror of the read circuit, since the gate-source voltage of the transistors of the current mirror tends to approach the conduction threshold Vt of the transistors. The duplication of the current by the current mirror becomes imprecise and the read circuit is very sensitive to noise.

Read circuit for memory adapted to the measurement of leakage currents


A handle cover structure includes two casings and a connecting element, and the two casings are engaged with each other to form a sleeve having a hollow inner side and at least one open end for sheathing on a handle. Each casing has an external surface facing an outer side of the sleeve, an internal surface facing an inner side of the sleeve, a first recess formed on the external surface of each casing, and a through hole penetrating into the internal surface of the casing; and the connecting element is flexible and disposed on the external surfaces of the two casings, and both ends of the connecting element are passed into the through holes from the first recesses of the casings, extended into the inner side of the sleeve, and fixed onto the internal surfaces of the casings respectively.

Most common tools used in our daily life come with a handle cover sheathed on a handle of the tools to achieve the anti-slip effect and improve the comfort of holding the handle and usually has a decorative element installed on the exterior of the handle cover to improve the aesthetic look. However the decorative element is attached onto the handle cover by adhesive, the decorative element may be separated from the handle cover easily due to uneven forces applied onto the handle of the tool or moisture entering into the handle to deform the handle and separate the decorative element from the handle. As a result, both of the use and appearance of the tool are affected adversely.


An apparatus and method are provided, for accessing extended registers within a microprocessor. The apparatus includes translation logic and extended register logic. The translation logic translates an extended instruction into corresponding micro instructions for execution by the microprocessor. The extended instruction has an extended prefix and an extended prefix tag. The extended prefix specifies register address extensions, the register address extensions indicating the extended registers, where the extended registers cannot be specified by an existing instruction set, and where the existing instruction set includes the x86 instruction set. The extended prefix tag indicates the extended prefix, where the extended prefix tag is an otherwise architecturally specified opcode within the existing instruction set, and where the extended prefix tag includes opcode F1 (ICE BKPT) in the x86 instruction set. The extended register logic is coupled to the translation logic. The extended register logic receives the corresponding micro instructions, and for accesses the extended registers.

1. Field of the Invention
This invention relates in general to the field of microelectronics, and more particularly to a technique for incorporating additional addressable registers into an existing microprocessor instruction set architecture.
2. Description of the Related Art
Since microprocessors were fielded in the early 1970's, their use has grown exponentially. Originally applied in the scientific and technical fields, microprocessor use has moved over time from those specialty fields into commercial consumer fields that include products such as desktop and laptop computers, video game controllers, and many other common household and business devices.
Along with this explosive growth in use, the art has experienced a corresponding technology pull that is characterized by an escalating demand for increased speed, expanded addressing capabilities, faster memory accesses, larger operand size, more types of general purpose operations (e.g., floating point, single-instruction multiple data (SIMD), conditional moves, etc.), and added special purpose operations (e.g., digital signal processing functions and other multi-media operations). This technology pull has resulted in an incredible number of advances in the art which have been incorporated in microprocessor designs such as extensive pipelining, super-scalar architectures, cache structures, out-of-order processing, burst access mechanisms, branch predication, and speculative execution. Quite frankly, a present day microprocessor is an amazingly complex and capable machine in comparison to its 30-year-old predecessors.
But unlike many other products, there is another very important factor that has constrained, and continues to constrain, the evolution of microprocessor architecture. This factor—legacy compatibility—furthermore accounts for much of the complexity that is present in a modern microprocessor. For market-driven reasons, many producers have opted to retain all of the capabilities that are required to insure compatibility with older, so-called legacy application programs as new designs are provided which incorporate new architectural features.
Nowhere has this legacy compatibility burden been more noticeable than can be seen in the development history of x86-compatible microprocessors. It is well known that a present day virtual-mode, 32-/16-bit x86 microprocessor is still capable of executing 8-bit, real-mode, application programs which were produced during the 1980's. And those skilled in the art will also acknowledge that a significant amount of corresponding architectural "baggage" is carried along in the x86 architecture for the sole purpose of supporting compatibility with legacy applications and operating modes. Yet while in the past developers have been able to incorporate newly developed architectural features into existing instruction set architectures, the means whereby use of these features is enabled—programmable instructions—are becoming scarce. More specifically, there are no more "spare" instructions in certain instruction sets of interest that provide designers with a means to incorporate newer features into an existing architecture.
In the x86 instruction set architecture for example, there are no undefined 1-byte opcode states that have not already been used. All 256 opcode states in the primary 1-byte x86 opcode map are taken up with existing instructions. As a result, x86 microprocessor designers must presently make a choice between providing new features and abandoning legacy compatibility. If new programmable features are to be provided, then they must be assigned to opcode states in order for programmers to exercise those features. And if spare opcode states do not remain in an existing instruction set architecture, then some of the existing opcode states must be redefined to provide for the new features. Thus, legacy compatibility is sacrificed in order to provide for new feature growth.
On area of growth that continues to plague microprocessor designers involves the number and use of addressable registers within a microprocessor. Early microprocessor designs provided for one or two general purpose 8-bit registers. Then, as computations within application programs became more complex, both the number and size of the general purpose registers grew. The present state of the art in microprocessors that are employed in desktop/laptop computing applications provides for less than 10 general purpose 32-bit registers. But even at present, there are application programming areas that are disadvantageously impacted because present day microprocessors do not provide more addressable registers for general purpose operations.
Therefore, what is needed is an apparatus and method that incorporate additional general purpose registers into an existing microprocessor instruction set architecture that has a completely full opcode set, and where incorporation of the technique additionally allows a conforming microprocessor to retain the capability to execute legacy application programs.

Mechanism for extending the number of registers in a microprocessor


Azimuth brake for wind power plants, includes at least two pairs of brake shoes arranged at a common brake disk and each having an actuator associated therewith. Each actuator includes a lever that is pivotable about an axis extending normal to the plane of the brake disk, and a transmission for translating the pivotal movement of the lever into an axial engaging movement of the brake shoes against the brake disk. The levers of at least two actuators are coupled by a common drive mechanism.

The invention relates to an azimuth brake for wind power plants, comprising at least two pairs of brake shoes arranged at a common brake disk and each having an actuator associated therewith.
Wind power plants have a pod, which carries the blade rotor and is rotatable about a vertical axis, so that the blade rotor may be directed into the wind. The azimuth brake has the purpose to fix the pod in its respective azimuth position and/or to dampen the rotary movement of the pod. The azimuth brake has a horizontal annular brake disk at which several pairs of brake shoes, e.g. 4 to 24 pairs of brake shoes, are arranged, so that a sufficiently high braking force may be exerted onto the brake disk. In conventional azimuth brakes of this type, the brake shoes are actuated hydraulically.
For the blade rotor of a wind power plant, DE 202 03 794 U proposes a brake which can be actuated electromechanically. The actuator of this brake comprises a lever that is pivotable about an axis extending normal to the plane of the brake disk, and a transmission for translating the pivotal movement of this lever into an axial engaging movement of the brake shoes against the brake disk. For actuating the brake, a drive mechanism, which is preferably an electromechanical drive mechanism, e.g. a motor with spindle drive, acts upon the lever. A high engaging force of the brake shoes is achieved by the lever action of the lever and the force translation in the transmission.


The invention relates to a turbine machine, in particular, a steam turbine, comprising an inner housing, a turbine shaft, mounted such as to rotate, characterized in that the inner housing and the turbine shaft are produced from differing materials. The turbine is made from a chrome steel with 9 to 12 wt. % of chromium and the inner housing from a chrome steel with 1 to 2 wt % of chromium.

A steam turbine as an embodiment of a turbomachine within the meaning of the present invention is to be understood as meaning any turbine or partial turbine through which a working medium in the form of steam flows. By contrast, gas and/or air flows through gas turbines as working medium, but this involves completely different temperature and pressure conditions than the steam in a steam turbine. Unlike gas turbines, in steam turbines by way of example the working medium at the highest temperature flowing to a partial turbine is at the same time also at the highest pressure. A steam turbine usually comprises a turbine shaft which is fitted with blades, is mounted rotatably and is arranged within an inner casing. As heated and pressurized steam flows through the interior of the flow space formed by the inner casing, the turbine shaft is made to rotate by the steam via the blades.
The blades of the turbine shaft are also known as rotor blades. Furthermore, it is customary for guide vanes to be mounted on the inner casing, engaging into the spaces between the rotor blades. The inner casing can also be referred to as the casing shell. A guide vane is usually held at a first position along an inner side of the steam turbine casing. It is usually part of a guide vane ring comprising a number of guide vanes which are arranged along an inner circumference of the inner casing. In this case, the air foil part of each guide vane faces radially inward.
Steam turbines or steam partial turbines can be divided into high-pressure partial turbines, intermediate-pressure partial turbines or low-pressure partial turbines. The entry temperatures and entry pressures of high-pressure partial turbines may be 600° C. and 300 bar.
There are known single-casing steam turbines which represent a combination of a high-pressure steam turbine and an intermediate-pressure steam turbine. These steam turbines are characterized by a common casing and a common turbine shaft and are also known as compact partial turbines.
Steam turbines for higher steam states usually use a material with a high chromium content. The material with a high chromium content is usually a chromium steel with a chromium content of 9 to 12% by weight. Hitherto, the same material used for the turbine shaft has also been used as material for the inner casing. This has been justified by the coefficient of thermal expansion needing to be identical for shaft and casing. The use of the material with a high chromium content for the turbine shaft and the inner casing leads to expensive designs of steam turbine.


Changes to a hierarchical organizational structure may be stored in different versions of a data structure depicting the hierarchical organizational structure. Each of these versions may include a validity period field representing a time period that the hierarchical organizational structure depicted in the version accurately reflects the organizational structure of the organization. Each of the versions may also be designated as active or inactive. In some instances, each of the versions may be designated as inactive except for a version that reflects the organizational structure of the organization at a particular time, which may change over time. Historical copies of versions may be stored and subsequently recalled to identify an organizational structure that was in effect at a particular time in the past. The recalled version may then be used to limit the results of a query to a selected node of the historical organizational structure.

Many organizations have hierarchical organizational structures. For example, organizations may be structured into different parent and subsidiary companies. Hierarchical structures may also be implemented within individual companies as different divisions, departments, and groups within a company may be organized hierarchically. For example, groups and division may be organized by product and/or geographic area, so that similar groups of products may be part of a same division covering a particular geographic area. Hierarchies may also be used to organize data by type, function, or other criteria. For example, cost and/or profit centers of an organization may be organized into hierarchical groups in a tree structure according to a product type, geographic location, department organization, or other criteria. One or more nodes in the tree structure may then be selected to identify particular data of interest in a query or other data inquiry.
In many organizations, these hierarchical structures may change periodically as the organization reorganizes, merges, acquires another entity, or otherwise restructures. As the hierarchical structures change, the data structure in the organization's computing systems representing the hierarchy must also be updated. In many instances, the data structure is updated by overwriting the existing the data structure with the new hierarchical information. While the existing data structure may then accurately reflect an updated hierarchy, this procedure may make it difficult to retrieve and use past hierarchical information when querying historical data.
The inventors perceive a need to timely update hierarchical data structures as a hierarchical structure of an organization changes while preserving and making accessible historical hierarchical structures.

Enablement of quasi time dependency in organizational hierarchies


A semiconductor memory device (1) comprises a memory cell array (100) in which memory cells each have a variable resistance element and the memory cells in the same row are connected to a common word line and the memory cells in the same column are connected to a common bit line, wherein during a predetermined memory action, the voltage amplitude of the voltage pulse applied to an end of at least one of the selected word line and the selected bit line is adjusted based on the position of the selected memory cell in the memory cell array (100) so that the effective voltage amplitude of a voltage pulse applied to the variable resistance element of the selected memory cell to be programmed or erased falls within a certain range regardless of the position in the memory cell array (100).

Research and development on various kinds of nonvolatile memory (nonvolatile semiconductor memory device) have been promoted recently, and among them, an MRAM (Magneto-resistance Random Access Memory), OUM (Ovonic Universal memory), a PRAM (Phase-change Random Access Memory) and an RRAM (Resistance Random Access Memory) that read a difference in resistance value as data have the advantages that there is no statistical physical limit regarding scaling.
In general, the PRAM and the RRAM are provided with a nonvolatile variable resistance element whose resistance value is changed when a voltage pulse having a certain threshold value or more is applied, and include a memory cell array having memory cells each including a variable resistance element without a selection element such as a transistor and a diode. Here, FIG. 2 is a schematic view showing one constitution example of the memory cell array. A memory cell array 100 is constituted such that memory cells each having a variable resistance element 103 are arranged in a row direction and a column direction, one end of each of the variable resistance elements 103 arranged in the same row is connected to a word line 102, and one end of each of the variable resistance elements 103 arranged in the same column is connected to a bit line 101. A resistance value of the variable resistance element 103 is changed when the potential difference between the bit line 101 and the word line 102 becomes higher than a certain threshold value VTH.
FIG. 13 shows one example of a memory cell array 200 including no selection element. The memory cell array 200 is a cross point type memory in which a variable resistor 202 and an upper electrode 203 that intersect with a lower electrode 201 at right angles are laminated on the lower electrode 201. Since the selection element is not used, an area occupied by a memory cell can be small, so that the memory has large capacity. Furthermore, since such cross point type memory is simple in structure, a multilayer structure can be easily provided and a high-integrated memory can be implemented.    Patent document 1: U.S. Pat. No. 6,204,139B1    Patent document 2: Japanese Laid-Open Patent Publication No. 2003-338607


A method of (and apparatus for) electrophoresis in which the gel temperature is controlled automatically. A sensor may measure a gel temperature and a processor may control a power supply for the electrophoresis process in response to that measurement. Measurements may be made at predetermined times (e.g., periodically) and the processor may determine control settings for the power supply based on a preferred temperature for the electrophoresis process. The preferred temperature for the electrophoresis process may be a predetermined temperature which is chosen so that the electrophoresis process operates at or near the highest speed which is unlikely to break the glass plates.

1. Field of the Invention
This invention relates to electrophoresis, particularly to regulating gel temperature during gel electrophoresis.
2. Description of Related Art
Electrophoresis is a process for separating chemical substances from one another by means of their differential molecular weights. The chemical substances may be naturally charged, or a charge may be applied to them prior to electrophoresis. The chemical substances may be embedded in a neutral medium such as a gel. An electric potential is applied to the mixture for a fixed time period, during which lighter molecules will move more quickly. At the end of the period, the lighter molecules will have moved farther than the heavier molecules. Thus, one application of electrophoresis is to determine relative proportions of chemical substances in a mixture.
Electrophoresis is commonly used to determining the sequence of base pairs in nucleic acids such as deoxyribonucleic acid (DNA) or ribonucleic acid (RNA). This process is called "sequencing". Although sequencing may be done automatically by certain specialized equipment, but the cost of such equipment is too high for the average researcher. Manual sequencing is often tedious and time-consuming.
It has been found that electrophoresis is faster when performed with higher voltages; and that higher voltages generate heat which elevates the gel temperature. If the temperature rises too high, the glass plates which are used in the electrophoresis process may break, generally ruining the results and requiring that the sequencing must be run again. An associated problem is that factors which may influence the temperature of the gel during electrophoresis may vary widely, making it difficult to control the temperature during electrophoresis accurately.
One method of the prior art has been for a researcher to "baby sit" the electrophoresis sequencing process, periodically checking the temperature to see if the glass is becoming too hot. Typically the researcher will check the temperature by hand, i.e., by feeling the surface of the glass plates. While this method of the prior art may achieve the objective of speeding up the electrophoresis process, it is subject to the drawbacks that it is inaccurate, unreliable, and of course occupies the time of the researcher.
Accordingly, it is an object of the invention to provide a method and system for performing electrophoresis under automated temperature control.

Electrophoresis temperature feedback controller