A disk drive includes a disk drive housing and a frame that supports the disk drive housing, wherein a thermally conductive elastic member is interposed between the disk drive housing and the frame for conducting heat in the disk drive housing to the frame and for isolating vibration.

The present invention generally relates to disk drives and more particularly to a frame structure of a disk drive that has a movable head or pickup.
In recent high-speed disk drives such as a magnetic disk drive called a hard disk drive, which carries information on a rigid magnetic disk, the speed of revolution of the disk is increasing for faster operation. Associated with this, the speed of movement of an actuator that carries a head is also increasing. In such high-speed disk drives, there is a keen demand for an improved design for efficient heat dissipation as well as for efficient suppression of vibration associated with such a high speed operation of the disk drive.
Typically, a magnetic disk drive has an actuator arm for carrying a magnetic head such that the magnetic head floats from the surface of the revolving magnetic disk by means of a thin air foil. By swinging the actuator arm back and forth about a swing axle, the magnetic head scans over the surface of the magnetic disk generally in a radial direction thereof.
FIG. 1 shows the construction of a typical conventional magnetic disk drive in a plan view.
Referring to FIG. 1, it will be noted that the magnetic disk drive includes an actuator 11 and a magnetic disk 12, wherein the actuator 11 carries an arm 13 that in turn supports a magnetic head 14 at a distal end thereof via a spring mechanism 13a. It should be noted that the arm 13 has a base part thereof held rotatably by a pivot mechanism 15 and swings back and forth about a swing axle of the pivot mechanism 15.
At the other end of the arm 13, there are formed support members 16a and 16b for holding a coil 17, and a pair of magnets 18a and 18b are disposed below the coil 17 with respective, opposite magnetic polarities. The magnets 18a and 18b are fixed on a chassis of the magnetic disk drive and form a voice coil motor 18 together with the coil 17.
The magnetic disk 12 is revolved by means of a spindle motor 12a, and the actuator 11 causes a scanning of the magnetic head 14 over the surface of the revolving magnetic disk 12 generally in a radial direction of the disk 12 in response to the energization of the coil 17. It should be noted that the actuator 11 is disposed on both sides of the magnetic disk 12, while the magnetic disk 12 is provided in plural numbers on a common drive axis such that the magnetic disks are revolved simultaneously and coaxially by the spindle motor 12a. The magnetic disks 12 and the actuators 11 are hermetically sealed by an enclosure or housing 19.
In recent magnetic disk drives, the speed of revolution of the spindle motor 12a is increasing for increased operational speed and reduced access time. Associated with such an increased speed of the magnetic disks, there is a demand for increased speed of movement of the actuators 11.
When the speed of movement of the actuator 11 is increased as such, there arises a problem of temperature rise in the hermetically sealed interior of the magnetic disk drive. Thus, there is provided a heat sink on the housing of the magnetic disk drive for dissipating heat. Further, the magnetic disk drive is mounted upon a frame for insulating vibration. Further, it should be noted that a plurality of such magnetic disk drives are assembled to form a disk module that provides a large storage capacity, several times as large as the storage capacity of the single magnetic disk drive.
FIGS. 2A and 2B show the construction of the frame structure used in conventional magnetic disk drives, wherein FIG. 2A shows a plane view while FIG. 2B shows a side view.
Referring to FIGS. 2A and 2B, it should be noted that a magnetic disk drive 21 is accommodated in a housing part 22, while the voice coil motor 18 that forms the essential part of the actuator mechanism 11 described previously, is covered by a another housing part 23. Further, FIG. 2A shows a heat sink structure 22a that includes a number of heat radiation fins for efficient dissipation of heat. The housing part 22 and the housing part 23 are connected with each other and form a hermetically sealed housing in which the rotary magnetic disks 12 and the actuators 11 are accommodated.
The magnetic disk drive 21 is mounted upon a U-shaped frame 24 that includes a pair of side plates 24a and 24b opposing each other, wherein the side plate 24a is provided with a support flange 25a as a part of the side plate 24a cut and bent inwardly. Similarly, the side plate 24b is provided with support flanges 25b and 25c as a part of the side plate 24b cut and bent inwardly. As will be described in detail below with reference to FIGS. 3A and 3B, the support flanges 25a and 25b carry respective vibration insulators 26a and 26b and support the housing part 22 of the magnetic disk drive via the vibration insulators 26a and 26b. Similarly, the support flange 25c carries a vibration insulator 26c and support the housing part 23 of the magnetic disk drive via the vibration insulator 26c. Thereby, the housing part 22 is fixed upon the support flanges 25a and 25b by way of screws 27a and 27b, while the housing part 23 is fixed upon the support flange 25c by way of a screw 27c and a mount bracket 28 attached to the housing part 23.
FIGS. 3A and 3B show the support flanges 25b and 25c in detail.
Referring to FIG. 3A, it will be noted that the vibration insulator is formed of a rubber sleeve having upper and lower rubber flanges 26b.sub.1 and 26b.sub.2 disposed at both sides of the support flange 25b, and the screw 27b is threaded into the support flange 25b through the sleeve of the vibration insulator 26b for fixing the housing 22 of the magnetic disk drive. Similarly, the housing 22 is mounted upon the support flange 25c by means of the screw 27c and the bracket 28, such that a rubber member acting as the vibration insulator 26c is interposed between the bracket 28 and the support point 25c.
The magnetic disk drive having such a conventional construction dissipates the heat generated inside the housing 22 by way of the heat radiation fins 22a on the housing 22. Further, the vibration caused by the spindle motor 12 or the voice coil motor 18 is suppressed by way of the vibration insulators 26a-26c. It should be noted that a plurality of magnetic disk drives each having a construction of the magnetic disk drive 21 are mounted upon corresponding frames 24, and such a plurality of the magnetic disk drives form the magnetic disk module mentioned previously.
In the recent high-speed disk drives, however, such a conventional construction of the housing 22 for heat dissipation is not sufficient for suppressing the temperature rise inside the housing 22. As a result of excessive temperature rise, conventional high-speed disk drives have suffered from the problems such as increased off-track, damaging or deterioration of mechanical parts such as bearings or flexible printed circuit boards, as well as deterioration in performance of the integrated circuits provided inside the housing 22. When forced-air-cooling is employed for eliminating this problem, on the other hand, one encounters a problem of excessive cost of the device. Thus, the problems pertinent to such conventional magnetic disk drives urge the development of a further improved design of vibration insulation that is also effective for efficient heat dissipation.

Frame structure of a disk drive for improved heat dissipation and a disk drive that uses such a frame structure


A mounting unit connects a coolant pipe within a radiator tank to a coolant supply pipe or a coolant return pipe outside the radiator tank. The mounting unit includes an engaging structure on the coolant pipe and an engaging flange on the coolant supply pipe or the coolant return pipe. The engaging structure includes a boss, a flange, a connecting hole, and an engaging bolt. The boss is configured to be inserted through a mounting hole of the radiator tank. The engaging flange includes a recess configured for the engaging structure to be inserted therein, a bolt hole configured for the engaging bolt to be inserted therein, and a connecting nipple configured to fluidly communicate with the connecting hole.

(a) Field of the Invention
The present invention relates to an oil cooler mounting unit for an automatic transmission.
(b) Description of the Related Art
A heat exchanger, called an oil cooler, is typically used to cool engine oil or transmission fluid in a vehicle. In an oil cooler for an automatic transmission, transmission fluid, also called oil herein for simplicity, is cooled in a radiator core.
In a down-flow radiator, as opposed to a cross-flow radiator, a coolant pipe is disposed within a lower tank of the radiator, and is connected to a coolant supply pipe and/or coolant return pipe by an oil cooler mounting unit.
A conventional oil cooler mounting unit includes a connecting pipe attached perpendicularly to an end of the coolant pipe. The connecting pipe has a screw thread on its external surface. The connecting pipe is inserted through a mounting hole of the lower tank and attached with a nut. The coolant supply pipe or coolant return pipe is engaged with an end of the connecting pipe with an additional nut.
The screw thread of the connecting pipe may be easily damaged by corrosion. To solve this, the connecting pipe is sometimes made of brass instead of aluminum, but brass is costly. Also, air-tightness between the connecting pipe and the supply or return pipe is not reliable.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

Oil cooler mounting unit for automatic transmission


A method of iris recognition using a cumulative-sum-based change point analysis and an apparatus using the same are disclosed. The method includes: transforming an iris image to a polar coordinated image having n×m pixel size and dividing the polar coordinated image into at least one cell; grouping the divided iris images into at least one of first groups having a predetermined number of cells, and at least one of second groups each having more cells than the first group has; performing a cumulative-sum-based change point analysis using a predetermined characteristic pattern value of each cell as a representative value; and generating a pattern vector by assigning a predetermined value to a cell having the change point and assigning a different value to other cells.

1. Field of the Invention
The present invention relates to a method of iris recognition to identify an authorized user and an apparatus using the same, and more particularly, to a method of iris recognition to identify an authorized user through simply and effectively extracting characteristics of iris using a cumulative-sum-based change point analysis (CPA) with less amount of calculation.
2. Description of the Related Art
Many methods of extracting characteristic patterns from iris were introduced. Among them, a Garbor transform and a wavelet method are widely known technologies to analyze the characteristic patterns of iris. Daugman introduced a conventional method of extracting characteristic patterns from iris using the Garbor transform and creating a pattern vector. Such a Daugman's method requires high quality iris image. Therefore, Daugman's method requires very expensive image processing equipment. Also, the computation complexity thereof is very high due to the calculations related to exponential functions and numerous multiplications. Furthermore, the obtained iris image is transformed into a polar coordinated image and the characteristic patterns are extracted from the polar coordinated image. In this procedure, some differences are generated between the obtained iris image and the polar coordinated image due to the position of iris is shifted. Therefore, the performance of iris recognition obtained through extracting and matching iris patterns is degraded.

Method of iris recognition using cumulative-sum-based change point analysis and apparatus using the same

Electronics and Telecommunications Research Intitute


An image forming apparatus includes a fixing device configured to include a pressure section and a heating section for heating an image receiving medium and to execute a fixing processing for fixing an image formed on the image receiving medium with a decolorable color material at a fixing temperature or an erasure processing for erasing an image at a decoloring temperature, a reading section configured to be arranged at the upstream side of the fixing device in the conveyance direction of the image receiving medium to read an identifier indicating whether or not the color material of the image formed on the image receiving medium can be decolorized, and a control section configured to control the execution of the erasure processing of the image on the image receiving medium with the fixing device according to a result of reading of the identifier with the reading section.

As a form, it is known that an image forming apparatus comprises a decoloring apparatus which uses a recording material, for example, a decolorable toner to print an image on a sheet, and then executes a decoloring processing on the toner forming the image by heating to erase the image printed on the sheet. It is known that the decoloring apparatus, which includes a reading section configured to read an image to keep the image previous to being decolorized and a decoloring section configured to decolorize the toner forming the image, carries out an image reading processing with the reading section once again to determine whether or not the decoloring processing is normally executed after the decoloring processing. Thus, at the time the image formed on the sheet is decolorized, a series of operations, that is, reading and storing content of the sheet through the reading section and then decolorizing the content, are executed.
In recent years, a writing material the ink of which is colorless according to the change of temperature caused by heat is widespread. Such a writing material is used in a wide range from the use of check or memo to the use of drawing. In this way, due to the wide use, the area to be decolorized when the recorded content is useless is also increased, and the labor and the time are required in the decoloring job by the dedicated eraser. The cases of decolorizing an image with a duplicating machine that is arranged in the convenience store and capable of decolorizing an image through the heat are increased in order to decolorize the content recorded with the writing material. The decolorable ink of the writing material becomes colorless at about 65 degrees centigrade. In the duplicating machine, if the useless sheet is put into the sheet feeding stage to be subjected to a blank paper copy processing, the discharged sheet is decolorized because of being heated at a fixing temperature which is about 180 degrees centigrade for the general toner and is higher than the decoloring temperature. Thus, there is a problem that the memo and figures or the recorded characters in the critical document that are required to be left are also decolorized according to the relationship between the colorless temperature of the ink and the fixing temperature of the toner.


The present disclosure provides a method for establishing a session, which is applied to a terminal device and includes sending a session establishment request to a network device. The session establishment request is used to request to establish a first session. The session establishment request includes first indication information. The first indication information indicates that the first session is a deactivated session or an activated session. The method also includes receiving a response message of the session establishment request from the network device. If the number of DRBs has reached a number threshold, the terminal device can request the network device to establish a deactivated first session via the first indication information. When the number of DRBs is less than the number threshold, the terminal device or the network device can activate the first session.

The present disclosure relates to the field of communications, and in particular to a method and device for establishing a session.
The 5th generation (5G) mobile communication system supports a protocol data unit (PDU) connection service. The PDU connection service is a service of transmitting PDU data packets between a terminal device and a data network. A data channel for transmitting the PDU data packets can be called a PDU session, which is also called a session for short.
In some scenarios, only a limited number of data radio bearers (DRB) can be used by the terminal device. For example, when the terminal device is accessed to a narrow band internet of things (NB-IoT), usually only two DRBs can be used simultaneously, and each DRB corresponds to one activated session. That is, the terminal device can usually use only two activated sessions simultaneously. If more than 2 activated sessions are used by the terminal device, a negative impact may be applied on communications of other NB-IoT devices. Therefore, how to prevent the number of activated sessions of the terminal device from exceeding a prescribed number is a problem that needs to be solved currently.

Method and device for establishing session

GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORP., LTD.


Defect analysis of a flip chip die having a back side opposite circuitry at a circuit side and a liquid crystal layer is enhanced using a method and system that makes possible the detection of the defect from the back side of the flip chip. According to an example embodiment of the present invention, a flip chip die having a liquid crystal layer is analyzed by detecting a liquid crystal phase change caused by heat generation at a defect in the die. By detecting the phase change associated with a defect, the defect can be located. The defect detection can be used through the back side of the die, and can be used to detect defects located near intrinsic heat sources that make conventional liquid crystal analysis difficult or even impossible.

The present invention relates generally to semiconductor devices and their fabrication and, more particularly, to semiconductor devices and their manufacture involving techniques for analyzing and debugging circuitry within an integrated circuit.
The semiconductor industry has recently experienced technological advances that have permitted dramatic increases in circuit density and complexity, and equally dramatic decreases in power consumption and package sizes. Present semiconductor technology now permits single-chip microprocessors with many millions of transistors, operating at speeds of hundreds of millions of instructions per second to be packaged in relatively small, air-cooled semiconductor device packages. A by-product of such high-density and high functionality in semiconductor devices has been the demand for increased numbers of external electrical connections to be present on the exterior of the die and on the exterior of the semiconductor packages which receive the die, for connecting the packaged device to external systems, such as a printed circuit board.
To increase the number of pad sites available for a die, to reduce the electrical path to the pad sites, and to address other issues, various chip packaging techniques have been developed. One of these techniques is referred to as controlled collapse chip connection or xe2x80x9cflip-chipxe2x80x9d packaging. With packaging technology, bonding pads of the die include metal (solder) bumps. Electrical connection to the package is made when the die is xe2x80x9cflippedxe2x80x9d over and soldered to the package. Each bump connects to a corresponding package inner lead. The resulting packages are low profile and have low electrical resistance and a short electrical path. The output terminals of the package, which are sometimes ball-shaped conductive bump contacts, are typically disposed in a rectangular array. These packages are occasionally referred to as xe2x80x9cBall Grid Arrayxe2x80x9d (BGA) packages. Alternatively, the output terminals of the package may be pins and such packages are commonly known as pin grid array (PGA) packages.
Once the die is attached to such a package the back side portion of the die remains exposed. The transistors and other circuitry are generally formed in a very thin epitaxially-grown silicon layer on a single crystal silicon wafer from which the die is singulated. The side of the die including the epitaxial layer containing the transistors and other circuitry is often referred to as the circuit side or front side of the die. The circuit side of the die is positioned very near the package and opposes the back side of the die. Between the back side and the circuit side of the die is bulk silicon.
The positioning of the circuit side near the package provides many of the advantages of the flip chip. However, in some instances orienting the die with the circuit side face down on a substrate is disadvantageous. Due to this orientation of the die, the transistors and circuitry near the circuit side are not directly accessible for testing, modification or other purposes. Therefore, access to the transistors and circuitry near the circuit side is from the back side of the chip.
As the manufacturing processes for semiconductor devices and integrated circuits increase in difficulty, methods for testing and debugging these devices become increasingly important. Not only is it important to ensure that individual chips are functional, it is also important to ensure that batches of chips perform consistently. In addition, the ability to detect a defective manufacturing process early is helpful for reducing the number of defective devices manufactured. With flip-chip technology, these methods for testing and debugging often require accessing the circuitry through the back side.
One integrated circuit analysis method involves using a liquid crystal material for detecting defects from the front side of an integrated circuit. Liquid crystalline materials have both crystalline solid and liquid characteristics. These characteristics enable their use for thermally analyzing an integrated circuit for defects. When the liquid crystal material is heated, its properties change. One such example change is a color change, and another change is an ordering transition. Available defect analysis methods use the change as an indication of temperature in an integrated circuit, which is useful for detecting defects that cause heat generation. By forming a liquid crystal layer on an integrated circuit, the response of the liquid crystal can be monitored and used to detect hot spots that are an indication of a defect.
One type of liquid crystalline material useful for front side defect analysis is calamatic liquid crystal material having nematic ordering. Calamatic liquid crystals have long, rod-shaped molecules, and those having nematic ordering change under temperature variation from a nematic to an isotropic state. In the nematic state, the liquid crystal alters the polarization of light incident upon it. When the liquid crystal changes to an isotropic state, the polarization of incident light is no longer affected. This change in the effect upon incident light is used to detect a temperature change in the liquid crystal material. The transition temperature at which the change occurs is dependent upon the particular characteristics of the material.
Typical analysis methods that use liquid crystals involve forming a liquid crystal layer on an integrated circuit, heating the circuit with an external source, and observing a change in the state of the liquid crystal. The liquid crystal layer is often formed by adding a solvent, such as pentane, to the liquid crystal material and then applying the material to the surface of an integrated circuit device with an eyedropper. The solvent evaporates, leaving the liquid crystal material behind. Other liquid crystal application methods include applying liquid crystal with a spreading strip, and applying a drop of liquid crystal on the chip and spinning the chip to spread out the liquid crystal. In addition, a liquid crystal emulsion may be used in place of the liquid crystal mixed with a solvent.
Once the liquid crystal has been applied, the integrated circuit is then heated with an external heater. The heater is used to bring the integrated circuit to within about 0.1 Kelvin of the transition temperature of the liquid crystal material. A microscope is directed at the liquid crystal layer. A suitable microscope includes a polarized light source and a linear polarizer (analyzer) in front of an eyepiece or camera. The integrated circuit is electrically stimulated, thereby heating a defect in the circuit and raising the liquid crystal material over the defect to its transition temperature. The liquid crystal material changes from nematic to isotropic phase, which is evidenced by a dark spot that is detected by the microscope.
It would be beneficial to be able to use the state change properties of liquid crystal for back side analysis of flip chip dies including defect detection. However, it has been discovered that the heat dissipation throughout the backside is prohibitive to accurate use of liquid analysis via the backside, and that certain types of integrated circuits have internal intrinsic heat sources that tend to overwhelm defect-related heat sources. Typical intrinsic heat sources include fast-switching circuits such as phase lock loops (PLL) and crystal oscillators. Such heat sources generate heat during normal operation that is significantly greater than heat generated by surrounding circuitry. These intrinsic heat sources make liquid crystal analysis of defective integrated circuits via the back side even more difficult because the intrinsic heat causes the liquid crystal to change phase.
Addressing the above and other concerns, the present invention is directed to a method and system for analyzing the back side of a flip chip die involving defect detection using a liquid crystal layer. The defect detection can be used via the back side of the die, and can be used to detect defects located near intrinsic heat sources that make conventional liquid crystal analysis difficult or even impossible. The present invention is exemplified in a number of implementations and applications, some of which are summarized below.
According to an example embodiment of the present invention, a method is adapted for analyzing a flip chip die having a back side opposite circuitry at a circuit side. A flip chip die having a liquid crystal layer formed over a thinned region in the back side is provided for analysis. The thinned region is located in a manner that facilitates sufficient heat transfer to the liquid crystal layer to enable the detection of a defect using a liquid crystal phase change. The die is electrically operated, thereby generating heat in the die circuitry. The heat causes a phase change in the liquid crystal layer, and a defect in the die is detected by detecting a portion of the liquid crystal changing phase. In this manner, liquid crystal analysis can be used for back side analysis.
According to another example embodiment of the present invention, a system is adapted to analyze a flip chip semiconductor die having a back side opposite circuitry at a circuit side and a liquid crystal layer. The system includes an arrangement adapted to provide a flip chip die having the liquid crystal layer formed over a thinned region in the back side. An electrical power supply is adapted to power the die and generate heat in the die circuitry. A testing arrangement is adapted to detect a defect in the die as a portion of the liquid crystal changing phase.
The above summary of the present invention is not intended to describe each illustrated embodiment or every implementation of the present invention. The figures and detailed description that follow more particularly exemplify these embodiments.

Flip chip defect analysis using liquid crystal


Techniques are described for automatic discovery of two or more virtual service instances configured to apply a given service to a packet in a software-defined networking (SDN)/network functions virtualization (NFV) environment. Virtual service instances may be deployed as virtual entities hosted on one or more physical devices to offer individual services or chains of services from a service provider. The use of virtual service instances enables automatic scaling of the services on-demand. The techniques of this disclosure enable automatic discovery by a gateway network device of virtual service instances for a given service as load balancing entities. According to the techniques, the gateway network device automatically updates a load balancing group for the given service to include the discovered virtual service instances on which to load balance traffic for the service. In this way, the disclosed techniques provide auto-scaling and auto-discovery of services in an SDN/NFV environment.

A computer network is a collection of interconnected computing devices that can exchange data and share resources. In a packet-based network, the computing devices communicate data by dividing the data into small blocks called packets, which are individually routed across the network from a source device to a destination device. Certain devices, referred to as routers, within a computer network maintain routing information that describes routes through the network. A "route" can generally be defined as a path between two locations on the network. Routers include a control plane that maintains the routing information, and a data plane that forwards received packets according to the routing information.
Network service providers provide services such as security, tunneling, virtual private networks, filtering, load-balancing, VoIP/Multimedia processing and various types of application proxies (HTTP, XML, WAP, etc.) to incoming packets. Service providers also provide content-specific services designed to improve the quality of a user's experience, for example, video streaming and caching. The network infrastructure of a service provider network typically includes a vast collection of access nodes, aggregation nodes and high-speed edge routers interconnected by communication links. These network devices typically execute various protocols and exchange signaling messages to anchor and manage subscriber sessions and communication flows associated with subscriber devices.
A software defined networking (SDN) controller and/or a network functions virtualization (NFV) orchestrator may be included in the network architecture to provide centralized control of the subscriber sessions and communication flows within the service provider network. An SDN architecture is often used to provide at least a degree of separation of the control plane and the data plane in network devices, and the abstraction of the control plane into a more modular and layered architecture. An NFV architecture provides virtualization to remove dependency on specialized hardware and to consolidate many different network equipment types onto industry standard high volume servers, switches and storage, which may be located in data centers, network nodes and in end user premises.

This patent is subject to a terminal disclaimer.

Auto discovery and auto scaling of services in software-defined network environment


A method for determining motion estimation in a set of video frames including the comparing of a first macroblock from a video frame in the set of video frames to a second macroblock in a reference video frame to determine a differential value. Then, the differential value is compared to a comparison value. If the differential value is not smaller than the comparison value, then the differential value is compared to a minimal differential value. If the differential value is less than or equal to the minimal differential value, then the differential value is stored as the minimum differential value. An apparatus for performing the method.

This invention is related to the field of use of image processing. More particularly, this invention is directed to a method and apparatus for motion estimation for digital video encoding.
Video image capture using a digital camera has become very prevalent. Video capture may be used for such applications as video concerning, video editing, and distributed video training. Many components of hardware and software need to work seamlessly to both get the video data (also referred to as a video xe2x80x9cstreamxe2x80x9d) from the hardware through the various layers of software on the personal computer (PC) and made visible on a display medium such as a monitor.
Motion estimation is performed in a variety of video encoding algorithms. For example, the moving pictures experts group (MPEG) standards for compression, decompression, processing, and coded representation of moving pictures, audio and their combination utilize motion estimation in their algorithms. See, Coding of Moving Pictures and Audio, International Organisation for Standardisation Organisation Internationale de Normalisation, ISO/IEC JTC1/SC29/WG11, June 1996.
Motion estimation is a pattern matching technique, and is extremely expensive for conventional computers to perform. Essentially, motion estimation involves comparing segments of one image frame against the previous image frame to determine if the new segment can be simply repeated at a new location rather than retransmitted. Image segments may be such sizes as 8 pixels by 8 pixels or 16 pixels by 16 pixels in size. For example, if an image is 640 pixels wide and 480 tall, it may be divided into 4,800 segments that are 8 square pixels in size if (i.e., 80 segments wide by 60 segments tall). At 30 images per second, there is a minimum of 144,000 segments per second on which to operate. Considering each pixel may be represented by many bits of information for color images (e.g., 1-bit for black and white image pixels, and 2 or more bits-typically 32-bits-for it color image pixels), billion of bits have to be processed per second.
Many current implementations require hardware compression in order to achieve xe2x80x9creal-timexe2x80x9d compression. That is because it takes more computational power to compress a video stream than it does to play it back. A significant part of the computation process involves motion estimation. Thus, it would be desirable to find a fast technique to compute motion estimation.
A method for determining motion estimation in a set of video frames including the comparing of a first macroblock from a video frame in the set of video frames to a second macroblock in a reference video frame to determine a differential value. Then, the differential value is compared to a comparison value. If the differential value is not smaller than the comparison value, then the differential value is compared to a minimal differential value. If the differential value is less than or equal to the minimal differential value, then the differential value is stored as the minimum differential value.

Method and apparatus for motion estimation for digital video encoding


To provide a technique of writing data efficiently on a storage medium and thereby play back a content continuously. Specifically, the file allocation table (FAT) of a storage medium is supposed to be read on a partial FAT basis and data is written by a preferred method for that reading method.

Recently, various types of digital appliances (such as optical disk recorders and camcorders) that can write and store digital data, representing a content, on a number of types of media including an optical disk such as a DVD, a magnetic disk such as a hard disk, and a semiconductor memory, have become more and more popular. The content may be a broadcast program or the video and audio that have been captured with a camcorder, for example.
Also, PCs often have the functions of recording, playing and editing a content lately, and may also be regarded as being included in those digital appliances. In writing data such as document data, PCs have used various media such as a hard disk, an optical disk and a semiconductor memory. That is why a file system that has a data management structure compatible with a PC such as a file allocation table (FAT) has been adopted in such media. The FAT 32 system that is often adopted currently can handle a file that may have a maximum size of 4 gigabytes or can manage a medium with a maximum storage capacity of 2 terabytes.
The bigger the maximum storage capacity of a medium, the longer the overall content recording duration. The optical disks, hard disks, semiconductor memories and so on are so-called "randomly accessible" media. Therefore, when a data stream representing a content with a long duration is stored on such a medium, it would be convenient if playback could be started from any arbitrary location of the content.
For example, Patent Document No. 1 identified below generates time map information, defining correspondence between a playback time and the address at which the AV data to play back at the time is stored, at regular time intervals from the beginning of a data stream. If the start time and end time, specified by the user, are converted into a start address and an end address, respectively, by reference to the time map information and if the data stored at those addresses are read, the content can start being played back at the specified time.
Meanwhile, a lot of storage media, in which the FAT file system has been established, are currently available for sale. For instance, a removable semiconductor memory (i.e., a memory card) usually has its file management done by an FAT file system.
In a semiconductor memory, the target recording address is specified on the basis of a data unit of 512 bytes, which is called a "sector". A logical address is allocated to each address on a sector-by-sector basis.
In an FAT file system on the other hand, the availability and non-availability of the storage areas are managed on the basis of a unit called "cluster". For example, if the semiconductor memory has a storage capacity of 2 gigabytes or less, then one cluster has a data size of 32 sectors (i.e., 16 kilobytes). In that case, a file system called "FAT 16" is used. However, if the semiconductor memory has a storage capacity exceeding 2 gigabytes, then one cluster has a data size of 64 sectors (i.e., 32 kilobytes). In that case, a file system called "FAT 32" is used.
In recording a data stream on such a semiconductor memory, the writing rate varies with the degree of continuity between the sectors to be written. For example, if the sectors to be written had non-serial numbers, then the writing rate would decrease. This is because if a written sector and a sector to be written were included in the same cluster, then the written data should be read once and rewritten and then new data should be written, thus causing a processing delay.
Stated otherwise, if writing is done continuously on a number of consecutive sectors or clusters, then data can be written at a higher rate than an ordinary writing rate that is supposed to be adopted in normal applications.                Patent Document No. 1: Japanese Patent Application Laid-Open Publication No. 11-155130

Abstract: A data processor writes a content data stream on a storage medium, on which a data storage location is defined based on a file allocation table (FAT). The processor includes: a control section for determining the amount of data to be read continuously until a portion of the data stream, which should be played back during a data stream reading suspended period, is acquired, the suspended period including at least a time for reading a partial FAT forming a part of the FAT; an area detecting section for detecting an available area, in which that amount of data is storable, from a partial area managed by a single partial FAT; and a writing section for writing the content data stream on the available area, whereby the data stream is readable, and the content is playable, based on the partial FAT.


An electrode plate is formed by a substrate and a plurality of patterned electrodes formed on the substrate. Each patterned electrode has a laminate structure including a first layer of nickel metal formed on the substrate and a second layer of copper formed thereon. The electrode plate may be prepared by a process including a step of etching such a multi-layer metal electrode-forming film formed on a substrate by spraying an etchant downwardly and uniformly onto the substrate while rotating the substrate at a rotation speed sufficient to allow quick liberation of the etchant from the substrate. The metal electrodes can be formed with good adhesion onto the substrate and with good width and thickness accuracy. By incorporating the electrode plate as a pair of substrates sandwiching a liquid crystal, a liquid crystal device free from transmission delay and rounding of voltage waveforms can be provided.

Liquid crystal devices of TN (twisted nematic) type, STN (super twisted nematic) type, etc., have conventionally adopted electrode plates comprising ITO (indium tin oxide) films, etc., as transparent electrodes formed on glass substrates in many cases.
The above-mentioned conventional transparent electrode (ITO) has a relatively large resistivity so that it is liable to cause a problematic delay in transmission of applied voltage waveforms according to recent demands for a larger display size and a higher resolution. Particularly, in a liquid crystal device using a ferroelectric liquid crystal requiring a smaller substrate gap or liquid crystal layer thickness on the order of 1.0-2.0 xcexcm, the transmission delay of an applied voltage waveform is liable to be noticeable. A reduced resistance may be given by use of a thicker transparent electrode, but such a transparent electrode having an increased thickness is liable to exhibit poor adhesion onto a glass substrate and require a longer time for film formation, thus resulting in an increased production cost.
In order to solve these problems, there has been proposed a liquid crystal device equipped with an electrode plate comprising a glass substrate having thereon low resistivity metal electrodes of aluminum, etc., and thereon transparent electrodes of ITO, etc., electrically contacting the metal electrodes. Further, in order to comply with demands for liquid crystal devices with a higher aperture ratio and a high speed responsiveness in recent years, it has been desired to develop a metal electrode material of even lower resistivity.
When using metal electrodes of copper having a lower resistivity than aluminum, it is possible to realize a higher aperture ratio and a higher speed responsiveness, but problems are liable to occur regarding adhesion between a glass substrate and a copper electrode layer and the corrosive nature of copper. As a solution to such problems, there has been proposed an electrode plate having a sectional structure as shown in FIG. 17 including a glass substrate 100 having thereon an adhesion layer 101 of chromium, a principal conductor layer 102 of copper and thereon a chromium-copper alloy layer 103 formed by sintering in a reducing atmosphere. The adhesion layer 101 and the principal conductor layer 102 may be formed by forming a chromium layer and a copper layer respectively by sputtering on the glass substrate, followed by etching in a prescribed electrode pattern.
When providing ordinary print circuit boards, the etching of a copper layer may be performed using an iron chloride solution, a copper chloride solution or a liquid acid mixture principally comprising nitric acid and phosphoric acid as an etchant (or etching liquid), and dipping a substrate coated with a copper layer together with an etching pattern in a vessel of the etchant or showering the etchant onto the substrate to etch the copper layer into a desired pattern.
However, in the electrode plate structure shown in FIG. 17 including a glass substrate 100 and a laminate film disposed thereon comprising a copper principal conductor layer 102 and a chromium adhesion layer 101 for enhancing the adhesion between the copper layer 102 and the glass substrate 100, the chromium layer 101 and the copper layer 102 cannot be patterned in a single etching step. More specifically, when an etchant as described above having an etching effect on both the chromium and copper layers is used for etching of the laminate layer, a cell effect occurs between the chromium and copper layers via the etchant. As a result, the layer of chromium (similar to molybdenum and titanium) having a larger ionization tendency (i.e., a smaller standard electrode potential) than copper is selectively etched to result in an abnormal undercut. The undercut may remain within a tolerable limit for an electrode or wire pattern having a width on the order of mm as in ordinary print circuit boards, but provides a serious problem for providing an electrode or wire pattern having a width on the order of 10 xcexcm. Thus, the undercut can lead to peeling of the laminate electrode pattern.
For the above reason, it is necessary to use an etchant reacting only on the adhesion layer metal and an etchant reacting only on copper and repeat the etching of the respective metal layers while changing the etchant. More specifically, in the case of providing a chromium adhesion layer, it is possible to effect selective etching of the chromium and copper layers in multiple steps using etchants selectively reacting on chromium and copper, but this requires a complicated process and a considerable processing time. Moreover, the chromium-containing etching waste liquid can provide another difficulty with respect to environmental pollution.
On the other hand, in the case of providing an adhesion layer of molybdenum or titanium, most etchants reactive with these metals are also reactive with copper and also cause the undercut problem. Incidentally, the use of a potassium ferricyanide solution allows selective etching of molybdenum, but simultaneously promotes the growth of a stable oxide film on copper. The oxide film functions as a passivation film against a copper chloride solution as a selective etchant for copper, thus preventing the copper etching. An acid solution containing nitric acid, etc., can effect etching of a copper layer coated with the oxide film, but this is also accompanied with the problem of undercut arising from the difference in ionization tendency.
On the other hand, in the dry etching process, such as the reactive etching process, etc., the above-mentioned problems arising from the difference in ionization tendency can be obviated, but the etching speed is too small for commercial application.
As another process for providing a patterned copper film without resorting to an etching process, it has been proposed to form an adhesion layer film of chromium, molybdenum, etc., by sputtering, followed by etching into an electrode pattern, and to selectively coat the patterned adhesive layer with copper by plating and also with a protective layer by plating, etc. This process obviates most of the practical problems mentioned above accompanying copper electrode production, but it is difficult to form an accurate film thickness on the order of xcexcm as required on an electrode plate for a liquid crystal device. Further, the adhesion layer formed by sputtering on the glass substrate shows a good adhesion onto the glass substrate, but shows a rather poor adhesion with a copper plating layer, thus possibly requiring another adhesion promoting layer between the adhesion layer and the copper layer.
From the above discussion, it is still desirable to provide an electrode plate with patterned electrodes by sequentially forming an adhesive layer and a copper layer on a substrate and then etching the layers in a prescribed electrode or wire pattern. In this instance, it is desired to effect simultaneous etching of the adhesive layer and the copper layer in a single etching step.
On the other hand, the wet etching process has been frequently used as an etching process for locally removing or patterning a film formed on a substrate not only for production of semiconductor devices and ornamental articles, because of a simple structure and a low production cost.
FIG. 11 is an illustration of such a wet etching process. Referring to FIG. 11, in this process, a vessel 81, such as a beaker, is charged with an etchant 82, in which a substrate 84 having thereon a pattern of resist 83 exposing portions to be etched is dipped for a prescribed period. After the prescribed time, the substrate 84 is taken out and washed with, e.g., a large amount of flowing water to terminate the etching. In this way, a film on a substrate can be etched into various patterns through a simple step according to the wet etching process.
In the wet etching process, however, a difficulty is sometimes encountered in that the etching speed can vary locally on the substrate depending on the affinity between the etchant and the film to be etched. For example, etching of an aluminum (Al) film may generally be performed using a liquid mixture of nitric acid, phosphoric acid and acetic acid (which may sometimes be called mixture acid aluminum liquid) and, in that case, the central portion of the film on the substrate is preferentially etched because of the difference in etching speed between the central portion and the edge portion on the substrate. On the other hand, etching of a copper (Cu) film may frequently be performed using a liquid mixture of ferric chloride and acetic acid. The mixture liquid provides a greater etching speed at an edge portion than a central portion of the Cu film on the substrate, thus causing a preferential etching at the edge portion.
Further, as the wet etching process proceeds isotropically by way of a chemical reaction between the film and the etchant, it is liable to cause a side etching phenomenon as shown at 90 in FIG. 12 (showing a side view of an etched film portion) wherein a portion below a resist 83 of a Cu film formed on a substrate 86 of, e.g., glass, is etched hemispherically. Because of the side etching, it becomes difficult to effect etching of a minute pattern on a micron order.
In order to obviate such difficulties with respect to etching speed distribution and side etching, there has been proposed a wet etching process utilizing a showering scheme (wherein the etchant is showered onto a substrate). As a result, it has become possible to effect etching of a pattern of several xcexcm, so that the showering process has been frequently used, particularly in an early period of semiconductor device production.
FIG. 13 illustrates such a showering scheme wet etching process. Referring to FIG. 13, an etchant 88 is showered from a number of nozzles 87, and a substrate 84 to be etched is moved under the shower of the etchant 88. As a result, the etchant 88 can be uniformly supplied to the entire area of the substrate 84 surface, and uniform etching over the entire surface becomes possible.
Further, in the showering scheme process, since the etchant 88 may be sprayed with a certain degree of directionality onto the substrate 89 surface, the amount of side etching 90 can be reduced as shown in FIG. 14 (compared with a conventional state shown in FIG. 12 described above), so that it can provide an etching pattern showing a higher aspect ratio.
On the other hand, in the production of semiconductor devices, a dry etching process has become popular due to high accuracy controllability and occurrence of less waste liquid in addition to the above-described demands for patterning of a laminate film of different materials and an etching pattern giving a high aspect ratio.
In the dry etching process, a film on a substrate is vaporized through a plasma reaction with a reactive gas to remove the film from the substrate. The dry etching process requires a reaction vessel to be placed under vacuum and a huge etching apparatus for processing of a substrate having a diameter of several tens cm. Accordingly, this process cannot be readily applicable to a larger size liquid crystal substrate required to meet the demand for larger size liquid crystal panels in recent years.
In semiconductor device production in recent years, the use of Cu films has been examined for providing lower resistivity electrodes or wires, but no reactive gases for providing a vaporizable copper compound have been discovered, hence, the dry etching process has not been successfully adopted therefor. Further, the dry etching process is accompanied with a problem that the substrate is liable to be damaged due to irradiation with charged particles.
For obviating the difficulties of the dry etching process, the wet etching process is again receiving better evaluation in recent years. Further, the problem of side etching which has been regarded as a defect of the conventional wet etching process can be solved by formation of a side wall protective film, thus allowing etching of a higher aspect ratio.
FIG. 15 illustrates a principle of the side wall protection film. A Cu etching process is explained for example. A mixture aqueous solution of ferric chloride and acetic oxide is generally used as the etchant, and ca. 1% of thiourea is added thereto. The etchant is sprayed onto a substrate 84 surface. As a result, a reaction according to the following formula (1) is caused at the Cu film 85 surface to form a deposition of insoluble matter 89, which inhibits the etching:
As shown in FIG. 15, the etchant 88 is sprayed onto the substrate 84 surface so that the bottom portion rather than the side wall portion of the Cu film 85 is preferentially eroded to provide a larger etching speed in a downward direction, thereby allowing a higher aspect ratio of etching than before.
On the other hand, known etching apparatuses include one wherein an etchant is sprayed onto a rotating substrate to be etched, and the showering scheme can be adopted for providing better controllability.
FIG. 16 illustrates such a spin coating apparatus adopting the showering scheme. Referring to FIG. 16, in the apparatus, a substrate 91 to be etched held on a rotating substrate holder 90 is rotated together with the holder 90. After the rotation of the holder 90 is stabilized, a nozzle 92 disposed above the substrate 91 is vibrated, and a changeover valve 93 is turned on to open an etchant pipe 94, thus spraying the etchant through a nozzle 92 onto the substrate 91 surface.
After etching for a prescribed period, the changeover valve 93 is switched to stop the etchant and open a pipe 95 for a rinse such as water, thus spraying the rinse onto the substrate 91 surface to wash off the etchant 94. The substrate rotation speed and the vibration speed of the nozzle during the etching may be appropriately adjusted depending on the combination of etchant and film to be etched.
In such a spin etching process wherein an etchant supplied to a substrate surface is liberated from the substrate due to a centrifugal force accompanying the substrate rotation, there are attained several advantages for providing an improved etching accuracy not attainable by the conventional wet etching process. These advantages include: a fresh etchant is less liable to be buffered with the etchant after the reaction; the etchant can be supplied over the entire substrate by an appropriately adjusted combination of substrate rotation speed and nozzle vibration frequency; and the etching time can be controlled with improved accuracy by shortening the distance between the etchant discharge nozzle and the etchant selection valve.
However, one difficulty with the spin etching process is that the etching termination point determination accuracy is inferior as compared to the dry etching process.
More specifically, in the dry etching process using a plasma reaction for etching, the reaction of the film on the substrate for gassification is accompanied with light emission in many cases, and the resultant emission spectrum is peculiar to the film material and the etching gas. Accordingly, by specifying a light emission spectrum and measuring an intensity change of the spectrum, it is possible to accurately evaluate the progression state of the etching.
In contrast thereto, in the wet etching process, no noticeable phenomenon like light emission is involved. Accordingly, the progression of the etching has been evaluated according to an etching time experimentally determined based on trial experiments performed in advance. However, the evaluation of the progression state according to the etching time requires an accurate stabilization of reaction speed as a critical factor so that it also becomes necessary to accurately control the etchant and the temperature of the substrate to be etched.
In this regard, a large amount of etchant is used in the wet etching process, and, in order to suppress the etching cost and minimize environmental pollution, it has been generally practiced to recover the etchant and repeatedly use the etchant. However, during such repeated use of the etchant, the etching speed can be lowered due to saturation of a reaction called xe2x80x9cetchant fatiguexe2x80x9d or the vaporization of a relatively volatile component in the case of an etchant comprising a mixture of several components which causes a compositional change of the etchant, the latter can even lead to an increase in etching speed.
Thus, even if accurate control of the etchant and the substrate temperature are attempted so as to provide an accurately stabilized reaction speed, it becomes difficult to effect stable etching control with good reproducibility due to factors, such as etchant fatigue, and also to evaluate etching progression with good accuracy.
Accordingly, an object of the present invention is to provide an electrode plate having thereon an electrode laminate of a metal adhesion layer and a principal conductor layer of copper which can be patterned with high accuracy through a single etching step, a process for producing such an electrode plate, a liquid crystal device equipped with such an electrode plate, and also a process for producing such a liquid crystal device.
Another object of the present invention is to provide a process and an apparatus for spin etching allowing accurate determination or evaluation of etching progression.
According to the present invention, there is provided an electrode plate comprising a substrate and a plurality of patterned electrodes formed on the substrate, wherein each patterned electrode has a laminate structure including a first layer of nickel metal formed on the substrate and a second layer of copper formed on the first layer.
According to the present invention, there is provided a process for producing an electrode plate sequentially comprising a first layer-forming step of forming a first layer of nickel metal on a substrate, a second layer-forming step of forming a second layer of copper on the first layer, and an etching step of spraying an etchant downwardly onto the first and second layers on the substrate while rotating the substrate, thereby etching the first and second layers in a prescribed pattern to form a plurality of laminated metal electrodes.
According to another aspect of the present invention, there is also provided a spin etching process, comprising the steps of fixing a substrate to be etched onto a substrate holder, and spraying an etchant onto the substrate while rotating the substrate holder to etch a surface of the substrate, wherein etching progression is monitored by illuminating the substrate with light, detecting a light quantity or a spectrum pattern of emitted light as reflected light or transmitted light from the substrate, and evaluating the detected emitted light from the substrate.
These and other objects, features and advantages of the present invention will become more apparent upon a consideration of the following description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings.

Electrode plate, liquid crystal device and production thereof


An image forming apparatus includes a developing device for developing an electrostatic latent image formed in a prescribed region on an image carrier corresponding to an original document with a charged developer to form a developer image on the image carrier, a transfer charger for transferring the developer image onto an image receiving medium from the image carrier, and a pre-transfer charger for applying an electric charge having the same polarity as that of the charged developer to the image carrier before transferring the developer image onto the image receiving medium. The apparatus further includes a controller for controlling the pre-transfer charger so that the electric charge is applied only to a given area extending from a front end of the prescribed region on the image carrier on which the developer image is formed, the given area smaller than the prescribed region.

1. Field of the Invention
The present invention relates to an image forming apparatus which forms a toner image on a photoconductive drum according to a photoelectrostatic process and more particularly to an image forming apparatus equipped with a pre-transfer drum charger which charges a photoconductive drum before transferring a toner image on a paper.
2. Description of the Related Art
An image forming apparatus using a photoelectrostatic process, for instance, an electrostatic copying machine contains an image reading portion to read an image to be copied and an image forming portion to form an image to be copied based on an image read by way of this image reading portion and output the formed image on a transfer material. This image forming portion has a paper conveying path to take a transfer material, that is, paper out of a paper stacker one by one and convey a paper having a transferred and fixed image to an exit port.
In recent years, an electrostatic copying machine equipped with a pre-transfer drum charger which charges a photoconductive drum before transferring a toner image formed on the photoconductive drum through the electrostatic process has been put for practical use in its image forming portion as described above. This pre-transfer drum charger is arranged around a photoconductive drum and between a developing device and a transferring device.
This pre-transfer drum charger charges an toner image formed on a photoconductive drum using AC voltage, DC voltage having the same polarity as that of a toner or AC voltage with DC voltage superposed.
Thus, as a result of the charging of a toner image by the pre-transfer drum charger, it becomes possible to discharge the surface of the photoconductive drum after the development and at the same time, enhance the electric charge retained by the toner image and efficiently transfer the toner image in the next transfer process and the separation process. Further, it also becomes possible to prevent occurrences of so-called re-transfer phenomenon wherein a toner to be transferred on a paper is returned to the photoconductive drum, image void, etc.
However, such a conventional pre-transfer drum charger has such problems as described below.
That is, as shown in FIG. 1, a developing device 33 has normally a small amount of a reverse charged toner B which has the polarity reverse to a normal toner A besides this normal toner A which has the positive polarity and is adsorbed to an image portion of a photoconductive drum 30 around a developing roller 33a.
The potential of the white ground portion, that is, the non-image forming portion of the photoconductive drum 30 is at, for instance, -30 through -150 V. On the other hand, the developing roller 33a of the developing device 33 is set at a higher potential than that of the white ground portion of the photoconductive drum, for instance, at -200V.
So, static electricity is added to the normal toner A charged with positive electric charge in the arrow direction shown in FIG. 1 and the toner A is attracted to the developing roller 33a having the higher negative potential. Thus, the white ground portion of the photoconductive drum 30 is not developed.
On the other hand, static electricity is added to the reverse charged toner B charged with negative electric charge in the arrow direction in FIG. 1 and the toner is attracted to the photoconductive drum 30 side which has the lower negative potential. Thus, the toner is adhered to the white ground portion of the photoconductive drum 30.
On a conventional pre-transfer drum charger, there are such problems that electric charge of the same polarity as the normal toner is uniformly given to the reverse charged toner B adhered on the non-image portion of the photoconductive drum in addition to the normal toner A adhered on the image portion of the photoconductive drum. As a result, the reverse charged toner B is also transferred on a paper in the next transferring process and the so-called fog is produced, deteriorating the quality of an image formed on a paper.
Further, in a developer comprising two ingredients having toner to develop an electrostatic latent image on a photoconductive drum and a carrier to feed these toners to a developing region, if the toner content increased from the 5 to 6% proper toner mixed ratio, that is, a toner concentration increased, a reverse charged toner content also increases. As a result, the fog level on a paper increases and the quality of image will be extremely deteriorated.

Image forming apparatus equipped with pre-transfer drum charger


Network device drivers that interface with a communication transport are described. In one aspect, a networked computing system includes the network device driver and the communication transport. The network device driver converts abstract network device calls to network hardware device specific calls. The network hardware device specific calls are transported from the network device driver via the communication transport to a network hardware device.

The use of corporate intranets, the Internet, and other complex networks has exploded over the past several years and continues to grow. People have become very comfortable with many services offered on the World Wide Web (or simply "Web"), such as electronic mail, online shopping, gathering news and information, listening to music, viewing video clips, looking for jobs, and so forth. One useful tool in networking involves the use of network device drivers that allow computers to interface with network hardware devices. Network device drivers often work by converting abstract calls (such as abstract Application Programming Interface [API] calls that are produced by a client) into hardware specific calls (e.g., hardware specific API calls) that can be understood by a network hardware device.
Relatively straight-forward network device drivers are most applicable to simple network configurations with relatively few servers, routers, links, and other such networking components. Unfortunately, as network configurations become more complex, the ability of network device drivers to effectively manage network configurations, and the ability of network device drivers to effectively perform their functions, is diminished. Much human interaction is often used to properly configure the network device drivers to ensure proper operation of the network. Accordingly, there is a need for improved techniques for designing and deploying network device drivers, especially in more complex networked systems.

Network device drivers using a communication transport


A dual lumen catheter is provided having an elongate body defining coaxial intake and return lumens and a junction containing a proximal end of the body with parts of the lumens in the junction constrained in side-by-side relationship. First and second connecting tubes are engaged in the junction and extend generally longitudinally away from the main body. The junction provides fluid continuity between the first connecting tube and the intake lumen and between the second connecting tube and the return lumen to permit the catheter to be used for simultaneous dual flow. The distal end of the catheter includes a conical transition portion at which the exterior diameter of the dual lumen main catheter section is smoothly reduced to that of an open-ended, single lumen cylindrical tip section of lesser diameter.

Hemodialysis treatments have been developed since the early 1960s using a variety of combinations and arrangements of catheters. The earliest treatments were conducted using two needles in the same vein, and this subsequently led to pioneer work done by Dr. Shaldon in England who used two flexible catheters which could be left in place for limited periods. It was recognized by some practitioners that it would be preferable to use a single incision rather than to use two incisions and this led to the development of techniques involving dual flow catheters. There are two basic types. The first to be attempted was a coaxial catheter with the intake lumen surrounding the return lumen. While this had advantages, there were some difficulties of manufacture. The other approach is to use side-by-side lumens either in individual tubes connected to one another or in a single tube divided by an interior septum so that the lumens are D-shaped. These structures also had advantages and disadvantages, the notable disadvantages being that because the lumens are side-by-side, the intake openings must be in one side of the catheter. As a consequence of this, if the catheter were to attach itself to the wall of a vein due to suction applied to the intake lumen, then the flow would stop. Medical staff then have to move the catheter by rotating it until blood again flows. This is a very delicate manipulation which is normally performed only by a qualified medical practitioner who must be available at all times in case the flow is discontinued.
The side-by-side structures have advantages in manufacture due to the fact that the two lumens can be created simultaneously in an extrusion. This has led to great activity in developing devices having side-by-side D-shaped lumens at the expense of coaxial structures. Nevertheless, due to the inherent disadvantages of the side-by-side structures, there has been renewed interest in developing suitable coaxial devices. This is primarily because the intake lumen can have openings in any part of the wall of the catheter. As a result, no matter where the catheter may rest against a vein, some of the intake openings remain patent. There is then less likelihood that the procedures must be serviced by a trained medical practitioner.
An early patent showing the use of coaxial tubing in haemodialysis treatments is U.S. Pat. No. 4,037,599 to Raulerson. This structure involves the use of a needle forming the return lumen and a coaxial sleeve which is tapered at its leading end to follow the incision made by the needle and to provide an intake lumen between the tube and the needle. This structure can not of course be left in place, but it is an indication of the approach to the use of coaxial tubes to form two lumens.
Another structure involving the use of a needle is found in U.S. Pat. No. 4,073,297 to Kopp. Again this structure involves a tube about a needle to define an intake lumen and blood is returned through the needle.
A further approach to co-axial dual lumens is found in U.S. Pat. No. 4,196,860 to McLaughlin. In this structure the intake lumen is open at its end, and blood is withdrawn down this lumen about the return lumen. Further structures of a similar kind are to be found in U.S. Pat. No. 4,202,332 to Tersteegen et al.
U.K. Patent Application No. GB 2017499 A teaches the use of a dual lumen coaxial catheter made of flexible plastics material. The inner tube projects beyond the outer tube to form a return lumen, and the intake lumen is tapered at its end to close about the return lumen. This kind of structure is also to be found in Canadian Patent 1,150,122 to the present inventor.
A contrasting structure is shown in U.S. Pat. No. 4,493,696 to Uldall. In this the outer tube converges to fit about the inner tube and then projects beyond the inner tube to form an extension of the inner tube at the tip. Although this contrasts with all of the previous structures mentioned, there are disadvantages in this arrangement. Notably that there is a discontinuity where the end of the inner tube terminates, and the rigidity of the tip is determined by the material of the outer tube, which of course must be sufficiently rigid to maintain its patency in use.
Another reference known to applicant and involving a coaxial dual lumen arrangement is found in U.S. Pat. No. 4,666,426 to Aigner, which uses the inner tube to form a tip.
These prior art structures suffer from contrasting design criteria which have the effect of limiting the acceptance of coaxial dual lumen catheters in hemodialysis. In all instances the tip section is made up of material formed from an extension of either the inner or outer tubes forming the dual flow portion of the catheter. As a result the tip section has the same physical characteristics as parts chosen to be sufficiently stiff to resist kinking, if the catheter should be bent. By contrast, it is desirable that the tip section be sufficiently soft and pliable to permit this section to take up the local shape of a vein containing the catheter, thereby to avoid applying distorting forces to the vein and to permit prolonged access with a suitable selection of materials.


A method for preparing collagenous biological tissues for use as implantable bioprosthetic material, and articles prepared thereby. The method generally comprises the steps of a) contacting the tissue with an aldehyde fixative to effect cross-linking of the connective tissue protein(s) and subsequently b) contacting the tissue with a polyglycidyl ether. The treatment of the crosslinked tissue with the polyglycidyl ether serves to mitigate the tissue's propensity to undergo calcification following implantation in the body.

In modern medical practice, numerous implantable devices or prostheses are formed wholly or partially of biological tissue which has been chemically "fixed" or preserved. The technique used for chemical fixation of biological tissues typically requires exposure of the biological tissue to one or more chemical agents which are capable of forming cross-linkages between connective tissue protein molecules present in the tissue.
Examples of fixed biological tissues which have been used as bioprostheses include cardiac valves, blood vessels, skin, dura mater, pericardium, ligaments and tendons. These tissues typically contain a matrix of connective tissue proteins which act as the supportive framework of the tissue.
Collagen and elastin are two connective tissue proteins which make up the connective tissue framework of most biological tissues. The pliability or rigidity of each biological tissue is largely determined by its relative amounts of collagen and elastin and/or by the physical structure and confirmation of its connective tissue frame work.
Each collagen molecule is made up of three (3) polypeptide chains intertwined in a coiled helical confirmation. The chemical fixatives (i.e., tanning agents) which are used to preserve biological tissues generally form chemical cross-linkages between the polypeptide chains within a given collagen molecule (i.e., intramolecular crosslinkages), or between adjacent collagen molecules (i.e., intermolecular crosslinkages).
Examples of chemical fixative agents which have been utilized to crosslink collagenous biological tissues include; formaldehyde, glutaraldehyde, dialdehyde starch, hexamethylene diisocyanate and certain polyepoxy compounds. Of the various chemical fixatives available, glutaraldehyde is the most widely used. Glutaraldehyde is used as the fixative for many commercially available bioprosthetic products, such as porcine bioprosthetic heart valves (i.e., the Carpentier-Edwards.RTM. stented porcine bioprosthesis; Baxter Healthcare Corporation; Edwards CVS Division, Irvine, Calif. 92714-5686), bovine pericardial heart valve prostheses (e.g., Carpentier-Edwards.RTM. Pericardial Bioprosthesis, Baxter Healthcare Corporation, Edwards CVS Division; Irvine, Calif. 92714-5686) and stentless porcine aortic prostheses (e.g., Edwards.RTM. PRIMA.TM. Stentless Aortic Bioprosthesis, Baxter Edwards AG, Spierstrasse 5, GH6048, Horn, Switzerland).
One problem associated with the implantation of bioprosthetic materials is that the connective tissue proteins within these materials tend to undergo calcification. Such calcification can result in undesirable stiffening or degradation of the bioprosthesis. Both intrinsic and extrinsic calcification are known to occur in fixed collagenous bioprostheses, although the exact mechanism(s) by which such calcification occurs is unknown.
Clinical experience and experimental data has taught that glutaraldehyde-fixed collagenous bioprostheses may tend to calcify sooner than bioprostheses which have been fixed by other nonaldehyde fixative agents. Such accelerated calcification of glutaraldehyde-fixed bioprostheses has been reported to predominantly occur in pediatric patients. (Carpentier et al., Continuing Improvements in Valvular Bioprostheses, J. Thoracic Cardiovasc. Surg. 83:27-42, 1982.) Such accelerated calcification is undesirable in that it may lead to deterioration and/or failure of the implanted bioprostheses. In view of this propensity for accelerated calcification of glutaraldehyde-fixed bioprostheses in young patients, surgeons typically opt to implant mechanical heart valves or homografts (if available) into pediatric or relatively young patients (i.e., patients under 65 years of age), rather than glutaraldehyde-fixed bioprosthetic valves. However, patients who receive mechanical valve implants require ongoing treatment with anticoagulant medications, which can be associated with increased risk of hemorrhage. Also, homografts are of limited availability and may carry pathogens which can result in infection.
The factors which determine the rate at which glutaraldehyde-fixed bioprosthetic grafts undergo calcification have not been fully elucidated. However, factors which are thought to influence the rate of calcification include:
a) patient's age; PA1 b) existing metabolic disorders (i.e., hypercalcemia, diabetes, etc.); PA1 c) dietary factors; PA1 d) race; PA1 e) infection; PA1 f) parenteral calcium administration; PA1 g) dehydration; PA1 h) distortion/mechanical factors; PA1 i) inadequate coagulation therapy during initial period following surgical implantation; and PA1 j) host tissue responses. PA1 a. preparing a biological tissue which contains connective tissue proteins; PA1 b. contacting the biological tissue with an aldehyde fixative (e.g., formaldehyde or glutaraldehyde) to effect crosslinking of the connective tissue proteins within the tissue; and PA1 c. concurrently with, or after, the completion of step (b), contacting the tissue with a polyglycidyl ether. PA1 (a) preparing a biological tissue which contains connective tissue proteins; PA1 (b) contacting the biological tissue with an aldehyde fixative, such as glutaraldehyde, to effect crosslinking of the connective tissue proteins within the tissue; and PA1 (c) concurrently with or after the completion of step (b), contacting the tissue with a polyglycidyl ether.
Many investigators have attempted to discover ways of mitigating the in situ calcification of glutaraldehyde-fixed bioprostheses. Included among these calcification mitigating techniques are the methods described in U.S. Pat. No. 4,885,005 (Nashef et al.) entitled Surfactant Treatment of Implantable Biological Tissue To Inhibit Calcification; U.S. Pat. No. 4,648,881 (Carpentier et al.) entitled Implantable Biological Tissue and Process For Preparation Thereof; U.S. Pat. No. 4,976,733 (Girardot) entitled Prevention of Prosthesis Calcification; U.S. Pat. No. 4,120,649 (Schechter) entitled Transplants; U.S. Pat. No. 5,002,2566 (Carpentier) entitled Calcification Mitigation of Bioprosthetic Implants; EP 103947A2 (Pollock et al.) entitled Method For Inhibiting Mineralization of Natural Tissue During Implantation and WO84/01879 (Nashef et al.) entitled Surfactant Treatment of Implantable Biological Tissue to Inhibit Calcification; and, in Yi, D., Liu, W., Yang, J., Wang, B., Dong, G., and Tan, H.; Study of Calcification Mechanism and Anti-calcification On Cardiac Bioprostheses Pgs. 17-22, Proceedings of Chinese Tissue Valve Conference, Beijing, China, June 1995.
Because none of the previously known calcification mitigation, technique has proven to be optimal for glutaraldehyde-fixed tissues. There exists a need in the art for the development of new methods for inhibiting or mitigating calcification of glutaraldehyde-fixed biological tissues.

Method for inhibiting calcification of aldehyde-fixed bioprosthetic materials


A stacked MOS configuration for use in short channel length analog circuit technologies is provided. The stacked MOS configuration comprises a plurality of short-channel MOS transistors coupled in series and sharing a common gate terminal. In an embodiment, a first peripheral transistor provides a drain terminal for the stacked MOS configuration. A second peripheral transistor provides a source terminal for the stacked MOS configuration. Adjacent transistors in the stacked MOS configuration are connected in a drain-to-source configuration.

With the current progress in scaling down MOS transistors to increasingly smaller dimensions, the trend is such that the dimensions involved will soon extend into the nanometer scale regime. As transistor geometries shrink, however, short-channel effects cause a variety of shifts in the behavior of MOS transistors away from conventional models.
In one aspect, the intrinsic gain of a short-channel MOS is around 20 dB, too low for many high-accuracy high-gain analog blocks. In another aspect, the gain variation due to temperature of a short-channel MOS can be up to 12 dB, complicating the design of short-channel temperature-insensitive analog blocks, such as bandgap and temperature sensor circuits.
One solution, commonly adopted in long-channel analog circuits, to improve the intrinsic gain of a transistor is to increase its channel length. Intuitively, widening the channel of a transistor increases its resistance, which, in turn, increases its intrinsic gain. In short-channel technology, however, this solution works adversely. In fact, an increase in the channel length of a short-channel MOS results in a decrease in the voltage required to deplete the channel, lowering the channel resistance and, consequently, the intrinsic gain of the MOS.
What is needed therefore is a high-gain MOS topology for short-channel analog circuits. Further, a MOS topology with reduced gain variation due to temperature is needed.

High voltage gain topology for analog circuits in short channel technologies


A thermally sensitive recording medium whose luster of printed part is excellent can be provided by a thermally sensitive recording medium of single layer or multi layers having at least a thermally sensitive recording layer that contains a colorless or pale colored electron donating leuco dye and an electron accepting color developing agent on a substrate comprising, containing a pigment whose aspect ratio is 30 or more in at least one layer formed on a substrate.

In general, a thermally sensitive recording medium having a thermally sensitive recording layer whose main components are colorless or pale colored electron donating leuco dye (hereinafter shortened to dye) and electron accepting color developing agent (hereinafter shortened to color developing agent) that develops color when heated with a dye is practically used widely. A thermal printer in which a thermal head is built in is used to record images on it. This thermally sensitive recording method has advantages that, noiseless at recording process, developing process and fixing process are not necessary, maintenance free, an apparatus is relatively cheap and compact and a obtained color is very clear, therefore, is widely applied in the field of a facsimile, a terminal printer of computer, an automatic ticket vendor, a recorder for measuring instrument or a handy terminal that is used in outdoor. As uses of this thermally sensitive recording medium, besides above mentioned output paper for various instruments, the thermally sensitive recording medium are becoming to be used in the field of a paper for note to which good preservability is required. Along with the diversification of uses, recording instrument itself is disversified and becoming high performance (high speed, compact), accordingly, for the thermally sensitive recoding medium, a product which has higher color developing sensitivity and can obtain high quality recorded image in all range from lower printing density to higher printing sensitivity.
In general, as the method to improve color developing sensitivity and quality of developed image, a method to improve smoothness of an under coating layer formed on the surface of a thermally sensitive recording medium or between a substrate and thermally sensitive recording layer by a super calendar is well known.
In Patent Document 1, for the purpose to provide a thermally sensitive recording material which is excellent in dot reappearance ability (quality of image), a technique to laminate first intermediate layer and second intermediate layer in order between substrate and thermally sensitive color developing layer, wherein Ohken smoothness of the first intermediate layer is 700 seconds or more and density of the second intermediate layer is 0.1 or less is disclosed. In Patent Document 2, a technique to contain scale shape silica particles in an intermediate layer formed between a substrate and a thermally sensitive recording layer is disclosed. However, in a case when the smoothness of the thermally sensitive recording medium is improved by means of super calendar, although high quality recorded image can be obtained, porosity (abiabatic ability) of the layers which construct a thermally sensitive medium is deteriorated by calendar pressure. Accordingly, thermal efficiency at the thermally sensitive layer is deteriorated and high color developing sensitivity can not be obtained. Further, recently, since the required level for quality of image is becoming higher, sufficient quality can not be obtained by only improving the smoothness of the surface of the thermally sensitive recording medium or the under coating layer.
Further, along with the diversification of uses, a thermally sensitive recording medium to which fixed informations such as logo mark or ruled lines are previously printed by a common printing method such as offset printing is becoming to be used more frequently, accordingly, a high lustrous thermally sensitive recording medium having aptitude for a common printing, especially high lustrous aptitude for a printed part is required.
In Patent Document 3, for the purpose to improve aptitude for a common printing and lustor of thermally sensitive recording medium, an art characterized to contain aluminum hydroxide in a thermally sensitive layer is disclosed and in Patent Document 4, an art to form a protecting layer for the purpose to obtain high lustrous thermally sensitive recording medium is disclosed. However, when a protection layer is formed, since heat conduction to a thermally sensitive recording layer becomes slow, not only disadvantages such as deterioration of sensitivity, deterioration of printing speed or increase of printing energy cause, but also a problem of production cost rising causes because numbers of coating layer are increased.
Further, for the purpose to obtain high color developing sensitivity, there is an art to blend a silica having high oil absorbing ability in a thermally sensitive recording medium and to fix fused dye and color developing agent, however, when silica is blended, since lustrous of a thermally sensitive recording medium is deteriorated, problem that high printing lustrous can not be obtained causes. As mentioned above, at the present time, a thermally sensitive recording medium having high color developing sensitivity and characterized that lustrous of printed part is high when printed by a common printing method such as an offset printing, is not obtained yet.
Furthermore, since basic leuco dye and color developing agent contained in a thermally sensitive recording medium can be easily dissolved in various solvent, the thermally sensitive recording medium has a problem that the developed color density is deteriorated when a developed image is contacted with chemicals such as plasticizer contained in an ink of water mark pen or oily mark pen or an adhesive. In Patent Documents 5 and 6, for the purpose to overcome said defect, an art to form a protecting layer containing a pigment and a resin as main components on a thermally sensitive recording medium is disclosed.
However, recently, uses of a thermally sensitive recording medium are extending widely, for example, for various tickets, receipt, label, for ATM use of bank, for inspection of city gas or water supply or for a note of cycle race or horse race. Therefore, severe requirement for feature of the thermally sensitive recording medium is rising, which is not required to a conventional thermally sensitive recording medium. Since these cases of use are mainly outdoor use, the function of an over coating layer, which can endure practical use in more severe environment compared with the conventional use such as rain, water, humid, sun shine or in a car of summer, becomes necessary. However, when such kind of protecting layer is formed, although stability can be improved, above mentioned disadvantage such as deterioration of sensitivity, deterioration of printing speed or increase of printing energy are caused, further, large friction is caused between pigment such as silica contained in a protecting layer with a head, a problem of abrasion of a head is caused when continuously used for long time.
(Patent Document 1) JP 2000-108528 A publication
(Patent Document 2) JP 2002-137542 A publication
(Patent Document 3) JP Patent No. 2786912
(Patent Document 4) JP H09-156222 A publication
(Patent Document 5) JP S48-30437 A publication
(Patent Document 6) JP S48-31958 A publication


A system for providing a mobile communication terminal, the position of which can be detected with location-based information that is associated with a detected position, and a method of service for providing the mobile communication terminal with the location-based information automatically and quickly by synchronizing with behavior of the mobile communication terminal. A location-based information intermediation method and a location-based information acquisition method are disclosed. Still further, the present invention provides the mobile communication terminal and the intermediation computer system for the method.

Four examples of prior art location-based information acquisition methods are now described.
Prior art 1 (JP-A 160076/1999) discloses a navigation unit that communicates with a destination facility (e.g. a restaurant) to send a predetermined message about a user name, reservation request and so on by e-mail when a vehicle on which the unit is mounted reaches within a predetermined distance from the destination facility on a map installed on the unit or the time required to reach the destination facility comes to a predetermined value.
Prior art 2 (ITS Congress '99 "Proposal of an Algorithm for Transmission and Cache of Location Dependent Data for In-Vehicle Computer System") discloses another navigation unit that receives a series of information that is necessary for driving such as landmarks located in the traveling direction, maps and so on successively when the vehicle reaches predetermined positions. This unit receives the series of information that is transmitted from a database through networks by way of radiowave transmission facilities and so on placed along roads everywhere. Furthermore, as an extension of this method, this unit obtains data on positions along a planned route in advance and in a unit. This configuration may solve the problem that if the data concerning the planned route has not been obtained in advance, too much time may be taken to retrieve data concerning landmarks, maps and so on in a database after the vehicle has arrived a predetermined position, and to receive and display the data, Therefore, the data may be displayed only after the vehicle has passed the position corresponding to the data.
Prior art 2 (ITS Congress '99 "Proposal of an Algorithm for Transmission and Cash of Location Dependent Data for In-Vehicle Computer System") discloses another navigation unit that receives a series of information that is necessary for driving such as landmarks located in the traveling direction, maps and so on successively when the vehicle reaches predetermined positions. This unit receives the series of information that is transmitted from a database through networks by way of radiowave transmission facilities and so on placed along roads everywhere. Furthermore, as an extension of this method, this unit obtains data on positions along a planned route in advance and in a lump. With this configuration, it may solve the problem that if the data concerning the planned route has not been obtained in advance, it takes too much time to retrieve data concerning landmarks, maps and so on in a database after the vehicle has arrived a predetermined position and then receive and display the data, and therefore the data may be displayed only after the vehicle has passed the position corresponding to the data.
However, the method as shown in prior art 2 may have the following problems when the vehicle changes its route or stops driving:
(1) Communication may often be performed uselessly (communication costs may often be wasted);
(2) An extra memory is needed in every navigation unit to store data for, e.g., four nodes (crossovers) in advance;
(3) This method cannot be adapted when the driving route has not been fixed beforehand;
(4) Since it is not indicated who prepares and updates a database, this method may lack in operational feasibility;
(5) Since the contents of the database are permanent, the navigation unit according to this method is totally equal in terms of functions to the conventional navigation units that store the map database on a storage device such as a CD-ROM or a DVD permanently.
Next, prior art 3 (JP-A 307035/1998) discloses a system for determining a position of a vehicle equipped with a (GPS) Global Positioning System receiver at a center and informing the vehicle of appearance of an information providing spot in the neighborhood of the vehicle by any communicating means. For example, in this system, the center monitors when a landmark, such as a gas station, approaches and informs the vehicle of situation that by telephone, FAX or a pager and the like.
However, the system shown in prior art 3 has a problem that significant communication costs are wasted uselessly since the vehicle must transmit location information to the center continuously regardless of presence of the landmark in the neighborhood. Further, since conventional navigation units have already implemented a function to notify to the vehicle of the approach of the landmark (the gas station in this example) by setting the gas station as a passing point, there is no need to take a trouble to communicate with the center. Moreover, in this system shown in prior art 3, the mobile communication terminal cannot know information that is provided by facilities and that would be updated daily such as, for example, "today's gasoline price—90 yen/liter, Aug. 10, 2000".
In addition, there has been another prior art wherein a mobile communication terminal unit that comprises a (PDA) personal digital assistant or a notebook PC equipped with communicating means such as a cellular phone or a PHS and so on, and position detecting means such as a GPS receiver and so on retrieves a facility such as a restaurant in the vicinity of the retrieving point on the Internet and displays the facility on a map in an overlapping manner. This system is intended to simply check whether there is a desired facility in the vicinity of a given position. The system may further be configured to display a detailed description when the user selects a mark of a particular facility.
However, the system described above has a problem that time-consuming manual operations and retrieval are needed to acquire information since the mobile communication terminal unit must access and retrieve sites on the Internet sequentially by manual operation while the mobile communication terminal unit moves. Further, it is not feasible because it may not be safe to operate the mobile communication terminal unit continuously while driving. Still further, timing to acquire the information may often be delayed in such system.
Each of the prior art location-based information acquisition methods as described above simply provides so-called landmark displaying function that gives notice when a predetermined destination facility approaches, or simply checks whether there is a desired type of facilities such as shops and restaurants in the neighborhood. Therefore, the information that is provided by the facilities and that would be updated daily or momentarily such as "today's articles for special sale till 5:00 p.m. are . . . " cannot be recognized automatically and quickly just prior to passing in front of the facilities. Further, in such prior art methods, it is impossible to acquire peripheral information about the area where the vehicle enters successively and automatically.
In view of the foregoing, this invention has been made, and it is an object of this invention to solve the problems described above and provide a location-based information intermediation and acquisition method that can access a desired information source by synchronizing with behavior such as a present position or a moving bearing angle, and acquire location-based information (contents) automatically and quickly. Further, this invention provides a mobile communication terminal and an intermediation computer system for implementing such method.