An apparatus and a method configured for the efficient delivery of a viscous material, such as bone cement, to a surgical site are described. A housing removably receives a large gauge syringe which is filled with the viscous material. The apparatus is a syringe-type assembly that uses at least one vibrating motor together with a plunger rod assembly. The method employs the continuous application of vibrational forces to the central barrel portion of the apparatus during the time that the viscous material is being delivered and/or applied in vivo. The vibration to the central barrel portion increases the tendency of the viscous material to flow thereby making delivery of such materials easier and more efficient.

Age, injury, trauma, and disease can cause degenerative changes in both the joints and bones of the body. At some point, these degenerative changes can become so advanced and/or debilitating that it becomes necessary to replace a damaged joint with a prosthetic device. In such cases, bone cement is often used to secure the prosthetic device to the natural bone. For those suffering from severer osteoporosis, procedures such as vertebroplasty and kyphoplasty use bone cement to stabilize and/or build up the vertebral bodies that have been weakened by compression fractures. These procedures can help prevent further fracturing of the vertebral bodies as well as relieve the pain caused by existing fractures.
When referring to bone cement it should be understood that bone cement includes any type of surgical cement used in any type of surgical procedure including: resorbable cement, bone graft material, bone substitute, bone filler or any other biologically compatible mixture that is highly viscous.
Bone cement is primarily a two component material, the first component being a powder and the other being a liquid. The cement may also include additional ingredients such as stabilizers, one or more antibiotics, contrast agent(s), and/or colorants. Typically, the powdered component is comprised of polymethylmethacrylate (PMMA) which copolymerizes with the liquid component, methylmethacrylate (MMA), upon mixing. The polymerization process can be divided into four different phases: mixing, waiting, working, and setting.
The mixing phase starts the moment the powder and liquid components come into contact with each other. During this phase the cement is thoroughly mixed to reduce the porosity of the cement and increase its mechanical strength. The mixing phase is also characterized by changes in cement viscosity. At the beginning of mixing, the cement viscosity increases slowly. As the polymerization reaction progresses, however, the cement rapidly becomes increasingly viscous.
In the waiting phase, the cement will achieve a suitable viscosity for delivery to the surgical site. At the beginning of the waiting phase, the cement has a sticky dough-like consistency. However, the optimal consistency for delivering the cement in vivo is attained when the cement loses this sticky quality. Loss of stickiness marks the beginning of the working phase.
In the working phase, the cement is no longer sticky and has a viscosity that is high enough to allow penetration into cancellous bone without leaking into the surrounding tissues. The duration of the working phase is relatively short-lived and, in part, depends upon the type of bone cement being used. For example, low viscosity cements have a relatively short working phase while high viscosity cements have a longer working phase. Cements with a longer working phase typically allow a surgeon more time to apply the cement before the cement enters the setting phase and begins to harden. Regardless of the type of cement used, the finite duration of the working phase necessitates an efficient and precise means for its delivery and application.
In the setting phase, the cement hardens completely and attains its full mechanical strength. Hardening is generally a temperature sensitive process and can be influenced by body temperature, the temperature of the operating room, and the temperature of the bone cement material itself. High viscosity cements are sometimes pre-chilled before mixing, which prolongs the working phase as well as the setting phase. Humidity can also affect the working and setting phases of bone cement.
Considering the time dependent relationship between the optimal viscosity for delivery of the cement to the surgical site and the onset of cement hardening, an efficient, effective and convenient means for delivering bone cement is highly desirable.

Vibratory syringe apparatus and in vivo delivery method


The brake booster has an envelope (10) with an axis of symmetry (X-X') separated sealingly by at least one movable partition (12) to define at least a first chamber (14) connected permanently to a source of low pressure and at least a second chamber (16). The second chamber (16) being selectively connected to the first chamber (14) or a source of high pressure through a three way valve structure actuated by a control rod (30,130). The three way valve structure has a plunger (28,128) which slides in a bore (26,126) of a piston (20,90) is connected to a control rod (30,130). The position of the plunger (28,128) in bore (26,126) selectively controls the communication between the first chamber (14) and the second chamber (16) or communication between the second chamber (16) and the source of high pressure. Piston (20,90) includes support structure (38,138) having first (46,48) and second (146,148) seals which co-operate with a cylindrical surface (34,134) on the plunger (28,128) and a median part (40,140) for guiding the sliding of the plunger (28,128) in bore (26,126).

Such boosters are well known in automobile technology and comprise in general an envelope within which is disposed a piston formed from a hub and a skirt. The piston defines a front chamber connected permanently to a source of low pressure and a rear chamber connected selectively to the front chamber or to a source of high pressure by a valve means. This valve means is actuated by a control rod which is capable of bearing, through the intermediary of the front face of a plunger, on the rear face of a reaction disc which is solid with a thrust rod, the thrust rod actuating a master cylinder. The valve means usually comprises a valve member whose annular front face co-operates with a first circular valve seat formed on the plunger and a second circular valve seat formed on the piston and of diameter greater than that of the first valve seat. A valve spring urges the annular front face towards the valve seats so that the front face is always in contact with at least one of these two seats.
Such boosters present several disadvantages. Thus, in order to ensure that communication between the front and rear chambers of the booster is closed off before opening communication between the rear chamber and the source of high pressure, it is necessary to manufacture the plunger and the piston hub with very tight tolerances to avoid the control rod having too long a dead stroke, or even to design the valve means in such a way that the "valve lift" between the valve and the first valve seat will be as small as possible.
An additional disadvantage of the known boosters resides in the fact that the only radial passage opened to the high pressure air towards the rear chamber during actuation as well as the only axial passage opened to the air from the rear chamber towards the front chamber during release of breaking, produce turbulence in the moving air, slowing the action of the booster and inducing operational noises which can become troublesome.
Another disadvantage follows from the concentric and substantially coplanar disposition of the two valve seats, which means that the flexible membrane of the valve member is subjected to a variable pressure differential between the high pressure which is substantially constant prevailing permanently within the tubular hub around the input rod, and the variable pressure prevailing in the annular chamber surrounding this part of the flexible membrane of the valve member, on one part of which is exerted the pressure prevailing in the front chamber of the booster and on another part of which is exerted the variable pressure prevailing in the rear chamber of the booster.
This pressure differential, which exists in the rest condition and in the phase of brake release, applies an axial force to the annular front face of the valve member which adds to the valve spring force and which the plunger of the valve must overcome during each phase of brake release to disengage the annular front face of the valve member from the first valve seat formed in the hub and re-establish the communication between the rear working chamber of the booster and the vacuum chamber, which requires the return spring of the input rod to be oversize and in particular results in the driver having to apply a high force to bring the booster into operation, this force being known in the art under the term of "step-in force".
In addition, as the valve member is formed of a flexible diaphragm fixed sealingly by its outer peripheral edge to the piston by means of a metallic cup which also serves as load bearer for the valve spring and for a return spring of the control rod, the assembly of the three way valve means in the piston hub is a delicate and complex operation, with a rejection rate which is not negligible and which causes a significant increase in the cost of the booster.
The document DE-A-3 445 118 attempts to offer a solution to these problems, by making the plunger in a design similar to the spool of a slide valve. The plunger is capable of sliding within a bore in the hub of the piston to close off or open two windows formed in the hub communicating with the rear chamber of the booster. Such a design still requires a very precise match between the bore of the hub in the piston and the plunger sliding in the hub. It also requires the presence of a seal member at the edges of one of the windows formed in the hub of the piston and of a seal member at the end of the plunger. These seals cooperate either with a rib on the plunger, or with the edge of one of the windows, and they are therefore liable to deteriorate very rapidly, which is harmful for the reliability of the booster they are fitted in. In addition, this document still only provides a single axial passage between the front and rear chambers, and a single radial passage between the high pressure source and the rear chamber, resulting once again in turbulence which generates operating noise and in reduced speed of operation of the booster

Pneumatic brake servo with an improved valve


Disclosed herein is an imaging method including: by an imaging device, detecting a user that can be present in a predetermined area; calculating three-dimensional coordinates of an eye and a hand of the detected the user; determining an imaging range on a basis of the calculated the three-dimensional coordinates of the eye and the hand of the user; and imaging the determined the imaging range.

The present disclosure relates to an imaging method and an imaging device, and particularly to an imaging method and an imaging device that enable photography using a camera installed in a photographing spot of a tourist resort, for example.
When a person visits a place as a so-called photographing spot in a tourist resort or the like, the person needs to carry a camera or the like with himself or herself to take a photograph on the spot.
In addition, even when a person carries a camera, in order to take a group photograph of a group to which the person belongs on the spot, it is for example necessary to ask a person outside the group to perform a shutter operation, or necessary for someone within the group to perform a shutter operation without being photographed in the group photograph. In addition, a timer function or a remote shutter function of a camera may be used.
A method for enabling a commemorative photograph to be taken using a camera installed in advance in a tourist resort or the like has been proposed for a case of not carrying a camera (see Japanese Patent Laid-Open No. 2004-282769, for example).


Methods and nodes are provided for efficiently establishing a route between a mobile node and a correspondent node in a Proxy Mobile Internet Protocol network. A return routability procedure is used between a local mobility anchor and a media access gateway on one hand, and the correspondent node on the other hand. The procedure is made without involvement from the mobile node. The procedure is such that the correspondent node handles return routability as per standard mobile IP mechanisms. Following this return routability procedure, a binding of an address of the mobile node with an address of the media access gateway is stored in the correspondent node. This binding allows data traffic to flow between the mobile node and the correspondent node without passing through the local mobility anchor.

Mobile Internet Protocol (IP) is a protocol that provides routing of IP datagrams to a mobile node (MN) as it travels through the Internet. The MN has a home IP address, which is used when the MN is located within a home domain. The home domain provides a subscription and a home address (HoA) to the MN. When the MN is located outside of the home domain, it acquires a care-of address from a visited domain. The MN informs the home domain of the care-of address allocated thereto by the visited domain in a so-called binding process. When a packet or datagram is received in the home domain identifying the HoA as a destination, while the MN is known to be roaming in the visited domain, the home domain forwards the packet towards the MN in a tunnel, with the care-of address as a new destination address. Mobile IP requires that the MN be capable of detecting whether it is located in the home or in a visited network, and acquiring a care-of address.
Using Mobile IP, MNs may connect to other nodes, usually referred to as correspondent nodes (CN). FIG. 1 shows a Mobile IP network architecture as described in the Mobile IP version 6 (MIPv6) specification found in an Internet Engineering Task Force (IETF)'s Request For Comment (RFC) number 3775, entitled "Mobility Support in IPv6", incorporated herein by reference. As can be seen in FIG. 1, an IP network 100 comprises a MN 110 in communication with a CN 120 on a link 122. The link 122 is unlikely to be composed of only one direct physical connection, but rather represents a series of links between routing equipments transparently enabling the communication therebetween. The way the series of links is used to transport traffic between the MN 110 and the CN 120 is irrelevant to the present description, as long as IP communication therebetween can be established.
The MN 110 has a permanently assigned HoA valid in a home network 127, which HoA is allocated upon initialization of the MN 110 in the home network 127. The allocation mechanism is well known in the art. The MN 110 is further in communication with a home agent (HA) 130 located in its home network 127. Among other functionalities, the HA 130 keeps a record of a foreign address of the MN 110 valid outside the home network 127. The foreign address is called care-of-address (CoA) in the context of MIPv6. The CoA assigned to the MN 110 changes in time as the MN 110 moves from one network to another. A record kept by the HA 130, referred to as binding in the context of MIPv6, ties the CoA to the HoA. A binding between the HoA and the CoA is also kept in the CN 120 for the purpose of reaching the MN 110. The HA 130 is also responsible for routing traffic received at the HoA to the MN 110. The received traffic is forwarded by the HA 120 on a link 125 toward the MN 110. It should be noted that the MN 110 may have multiple home and care-of addresses, and that a binding should be kept at the HA 130 for each HoA-CoA pair.
Following now is an example of how the MIPv6 concept applies in a typical situation. For the benefit of the example, the MN 110 is in bidirectional IP communication with the CN 120 on the link 122. When the MN 110 moves from a first network to another, as illustrated by an arrow 135 on FIG. 1, the MN 110 receives a new CoA. This modification in addressing state of the MN 110 must be advertised to the CN 120 and to the HA 130. Prior to the advertisement, the MN 110 must first make sure that the HoA, which did not change, is still valid and that the newly acquired CoA address is usable to communicate with the CN 120. This assessment is done via a return routability (RR) test or procedure. The RR procedure also allows the creation of an authentication key, used to ensure that the advertisement procedure is made under trust between communicating parties. For this purpose, a care-of init cookie and a home init cookie are built by the MN 110, also protecting the RR procedure from being maliciously intercepted or interfered by a third party.
The RR procedure starts at the MN 110, which sends a home test init (HoTI) message through the HA 130, on the link 125, using its HoA as a source address. The HoTI message contains the home test init cookie and is addressed to the CN 120. Upon reception of the HoTI message, the HA 130 forwards it to the CN 120 on a link 140. The link 140 has similar characteristics as the link 122. Simultaneously to sending the HoTI message, the MN 110 sends a care-of test init (CoTI) message containing the care-of init cookie toward the CN 120 on the link 122, with its new CoA as the source address.
Upon reception of the CoTI message, the CN 120 replies with a care-of test (CoT) message addressed to the source address of the CoTI message, which is in the case the new CoA of the MN 110, on the link 122. The CoT message contains the care-of init cookie and a care-of keygen token generated by the CN 120. Upon reception of the HoTI message, the CN 120 replies with a home test (HoT) message addressed to the source address of the HoTI message, which is the HoA of the MN 110, on the link 140. The HoT message contains the home init cookie and a home keygen token generated by the CN 120. Reception of the CoT and HoT messages at the MN 110 successfully completes the RR procedure. The MN 110 keeps the content of both the HoT and CoT messages and then continues with the advertisement of the modification of its CoA toward the CN 120 and the HA 130.
In order to advertise any modification to its CoA, the MN 110 sends a first binding update (BU) message to the HA 130 on the link 125 containing the newly acquired CoA and other information related to the HA 130 binding. The HA 130 then updates its corresponding binding and replies to the MN 110 with a first binding acknowledgment (BA) indicating the successful update of the binding. The MN 110, after sending the first BU, uses the care-of keygen token and the home keygen token received earlier from the CN 120 to generate an authentication key valid between the MN 110 and the CN. The authentication key is commonly referred to as binding management key (Kbm) in the context of MIPv6. The MN 110 then creates a second BU similar to the first BU, signs it with the authentication key and sends it to the CN 120 on the link 122. The CN 120, upon reception of the second BU or before, generates the same authentication key using the tokens it already generated and further verifies the received second BU before updating its own related bindings. The CN 120 then creates a second BA, signs it using the authentication key and sends it, in accordance with the MIPv6 specification, on the link 122, addressed to the MN 110. Reception of the second BA at the MN 110 indicates the successful completion of the advertisement of the modification.
Many devices, such as laptops or personal assistants, may be moved by their users, but do not have the above described capabilities. Alternatively, the user of a mobile device may elect to disable its Mobile IP capability, for example to reduce signaling on a wireless link between the mobile device and an access point of a visited domain.
Proxy Mobile IP (PMIP) provides mobility capabilities to MNs that do not support mobility as defined in the MIPv6 specification. With PMIP, the MN does not need to support any mobility related signaling. Mobility features are solely supported by the network. The care-of address that was assigned by a visited network to the MN, in Mobile IP, is replaced in PMIP by a proxy care-of address (pCoA). The pCoA is the address of a gateway that provides connectivity to the MN. A description of PMIP is made in RFC 5213, entitled "Proxy Mobile IPv6", from the IETF, incorporated herein by reference.
FIG. 2 (Prior Art) shows a Proxy Mobile IP (PMIP) network 200, consistent with PMIP RFC 5213. The network 200 comprises three subnetworks owned by three distinct operators A, B and C. An access network 210 of operator A comprises a local mobility anchor (LMA) 220, sometimes called local mobility agent, and two media access gateways (MAG) MAG1 and MAG2, which are also sometimes referred to as proxy mobile agents. The LMA and MAGs provide PMIP support to MNs. Mobile nodes, for example MN1, MN3 and MN2, are subscribed in the subnetworks of operators B and/or C, but are currently located within the access network 210 of operator A. The LMA is used within operator A's subnetwork to manage local mobility. In an exemplary fashion, MN1 and MN3 are connected to MAG1 and MN2 is connected to MAG2. The MNs may be connected to the MAGs directly or through access points (not shown), which may be wireless access points. Of course, those skilled in the art will recognize that the subnetworks of each operator may comprise a plurality of MAGs and LMAs. Also, the subnetworks would comprise supplementary nodes such as routers, home agents, foreign agents, authentication servers, databases, and the like. Those supplementary nodes are not depicted in FIG. 2 for ease of the description of the problems present in the prior art.
When a given MN attaches to a domain that supports PMIP, it sends an access request, possibly through an access point. The access request arrives at a MAG. The MAG sends information about the access request to the LMA in a Proxy Binding Update (PBU) message. The access request may also be forwarded from the MAG to an authentication server (not shown) for authentication and profile retrieval. The PBU comprises an address of the MAG, called proxy care-of address (pCoA), to be used as a care-of address of the MN. The LMA stores in a binding cache the pCoA with a home network prefix (HNP) of the MN. The LMA replies to the MAG with a proxy binding acknowledgement (PBA) message carrying the HNP of the MN. Having received the PBA, the MAG advertises the HNP on a link to the MN. This makes the MN act as if it was connected on a home link, and the MN uses the HNP to configure for itself a HoA. If the MN is roaming, implying that the LMA is not part of the home domain for the MN, the LMA builds a regional care-of address (rCoA) and sends the rCoA to the home domain of the MN, thereby making the home domain forward traffic intended to the MN as per the Mobile IP protocol. In a first global mobility process, a packet intended for the MN is sent from the home domain through the LMA by use of the rCoA. Then, in a second local mobility process, the LMA encapsulates this packet and tunnels it to the MAG by use of the pCoA. The MAG receives this packet, decapsulates it, and sends it to the MN. Packets originating from the MN are sent through the MAG to the LMA and then to their destination addresses.
The RFC 5213 that defines PMIP requires that all traffic exchanged between the CN and the MN be tunneled between the MAG and the LMA. That specification does not allow any route optimization; in fact, the specification expressly states that the RR procedure defined in the RFC 3775 is not applicable under PMIP. When the MN is in communication with a CN located outside of the MN's PMIP domain, this tunneling is highly inefficient because it neither accounts for the respective locations of the MN and the CN nor benefits from potential high bandwidth links that may be available between the MN and the CN.

Efficient routing between a mobile node and a correspondent node in a proxy mobile IP network


Systems for and methods of drying a wet skin of a wet skinned ceramic ware are disclosed. The wet skinned ceramic ware includes a dry interior web with an outer surface. The wet skin is disposed on the outer surface of the dry interior web. The method includes generating an airstream and then directing the airstream through a first end of the wet-skinned ceramic ware only through an annular portion of the interior web that is adjacent the outer surface of the interior web. The flow of the airstream through the annular portion of the interior web causes moisture in the wet skin to migrate inwardly toward the interior web. The moisture is removed from the annular portion of the interior web when the airstream exits a second end of the ceramic ware, thereby drying the skin from the inside out of the wet-skinned ceramic ware.

Ceramic greenwares having an array of channels are formed, for example, by extrusion or casting and then processed (i.e., dried and fired) to form ceramic articles or "ceramic wares." These ceramic wares can be further processed to form filters and catalytic converters having a honeycomb porous structure for use in exhaust-producing engines and related applications. Ceramic greenwares can be formed by extruding a plasticized batch comprising ceramic-forming components, or ceramic precursors, through a die, such as a die that produces a honeycomb structure, to form an extrudate of the ceramic-forming material. The extrudate that exits the extruder is cut transversely to the direction of extrusion to form a greenware piece. The piece may itself be transversely cut into shorter pieces after drying.
The ceramic ware dimensions can vary due to drying and firing shrinkage during manufacturing. Ceramic wares can also be difficult to manufacture to the stringent external dimensional requirements set by original equipment manufacturers (OEMs) and the supply chain. To help ensure compliance with dimensional requirements, ceramic wares can be machined or "contoured" to a desired dimension. A thin layer of ceramic cement is then used to form an exterior skin that provides a smooth protective outer surface for the ceramic ware.

Systems for and methods of drying the skin of a cellular ceramic ware


An apparatus for cleaning a carcass includes an elongate housing having a forward and a rearward frame disposed in parallel, transversely opposed relation to one another. The elongate housing includes a plurality of stations. At least one rotating device at each station is disposed on the forward or rearward frame. A first station may include a pair of transversely opposed counter-rotating devices disposed at a common downward angle relative to a longitudinal axis of the elongate housing. A second station includes a plurality of rotating devices positioned near the top of the apparatus to clean the hoof and ankle area. A third station includes a plurality of vertically stacked rotating devices. A fourth, fifth, and sixth station include plural rotating devices in axial alignment with one another that are collectively oriented in a predetermined downward slope relative to the longitudinal axis to clean a carcass from top to bottom.

1. Field of the Invention
This invention relates, generally, to devices that clean animal carcasses. More particularly, it relates to a hide-on washer that removes organic matter from animal carcasses.
2. Description of the Prior Art
The purpose of washing animal carcasses after slaughter and prior to hide removal is to reduce or remove organic matter and pathogens that are likely to be present on all carcasses, thus lessening the chances of cross-contamination from hide to raw meat.
A problem exists in cleaning whole animal carcasses after they have been killed and prior to the hide being removed. Conventional hide-on carcass washing, whether manual or mechanical, uses high volumes of water often boosted to high pressures.
The known conventional methods are inadequate to remove sufficient amounts of organic material and pathogens.
However, in view of the prior art considered as a whole at the time the present invention was made, it would not have been obvious to those of ordinary skill in the art how to develop an apparatus capable of removing such organic material and pathogens from a carcass in a more effective manner.


In storage subsystems such as winchester disk, blocks of sequential data corresponding to sectors are concurrently accessed by the disk and the host. Semiconductor memory devices for storing block data are often utilized as storage location for sectors of data read or written to the disk and the host. Application of a semiconductor memory which increases the effective transfer rate of the system is highly desirable particularly in disk storage systems. A semiconductor memory for use in disk storage applications where information is transferred in blocks of data is hereby disclosed. Specifically, the memory includes a main memory configured as a random access memory array having rows and columns, each row having a plurality of n-bit words, a secondary memory having a data register file, first and second parallel-by-bit interfaces and a transferring circuit for transferring data between the main and secondary memories. Access to the main memory through a first interface is achieved independently of accesses to the secondary memory through a second interface thereby allowing concurrent accesses. Accordingly, concurrent and independent semiconductor memory accesses by any two utilization devices located externally to the memory such as a host, a disk sequencer, an ECC logic or a microcontroller are performed without corruption of the data. Further included in the secondary memory is a mask register file for maintaining the integrity of adjacent blocks of data when a block or sector of data having more words than the number of words in a row of the main memory is affected.

FIG. 1 shows the block diagram of the electrical system 1 of a typical winchester disk drive storage subsystem, having a host interface 5, a disk interface 2-4, a serial interface 8, a microcontroller 10, a microcontroller data bus 6, a microcontroller address and control bus 7, a non-volatile semiconductor memory such as an Electrically Programmable Read Only Memory (EPROM) 20 for storing code executed by the microcontroller and, a code/data RAM 30 for storing parameters, and variables used by the microcontroller 10. A typical Winchester disk array storage system may also have a Controller 40, a local buffer RAM 50, a R/W Channel 60, a Motion Control 70, a Servo Driver 81, and a Motor Driver 82. The controller 40 includes a host Interface Control 41, Buffer Control 42, Sequencer 43, Error Checking and Correction (ECC) 44 and a first micro Interface 45. The Motion Control 70 includes a Servo Control 71, a Motor control 72, and a second micro Interface 73.
The local buffer RAM 50 is used for temporary storage of data between the host and storage system add and if the storage subsystem employs caching, then also for storage of cached data of the storage subsystem. The local buffer RAM 50 must support a bandwidth that allows the concurrent transfer of data from host, disk, ECC and the microcontroller. The buffer control 42 controls access to the local buffer 50, by different utilization devices, namely host, disk, on the fly correction circuitry of the ECC, and the microcontroller 10.
With the continuous increase in the disk transfer rates and the transfer rate at the host interface, the local buffer RAM must support higher bandwidth. The ATA-2 standard requires host transfer rates up to 22 Mbyte/sec. The SCSI-2 standard requires host transfer rates of 10/20 Mbytes/sec (8-bit SCSI bus/16-bit SCSI bus) and proposed UltraSCSI standard requires host transfer rates of 20/40 Mbytes/sec (8-bit SCSI bus/16-bit SCSI bus). The disk transfer rates are increasing to 10-20 Mbytes/sec. Therefore the local buffer RAM must support bandwidths of 20-60 Mbytes/sec. In the prior art in order to increase the buffer bandwidths, the size of buffer RAM data bus is increased to 16 or 32 bits. Bandwidths up to 40 MBytes/sec can be achieved with commercially available DRAMs having 16 bit data bus.
The code/data RAM 30 is used for storing parameters and variables used by the microcontroller firmware. It can also be used to store part of the firmware code that is executed by the microcontroller 10. A drawback of storing code only in ROM is that once ROM or EPROM is programmed, making changes is costly and requires scrapping ROMs which have been previously manufactured. Executing code from RAM provides the flexibility of making changes and/or additions to the code. In systems that execute code from RAM, the microcontroller executes the code from a boot ROM during power-on initialization to load the RAM with code which is stored on the storage media itself.
To reduce the cost of the electrical system of the storage subsystem, it is desirable to combine the local buffer RAM 50 with the code/data RAM 30. The ProDrive Low Profile Series 270/340/540 of 3.5-inch hard disk drives for AT and SCSI bus from Quantum Corporation employs an architecture in which the code/data RAM is combined with local buffer RAM, and the code/data used by the microcontroller (previously stored in a separate RAM) is also stored in the local buffer. In these drives the maximum disk transfer rate is 46 Mbits/sec. The drives for AT bus support ATA transfer rates of 6 Mbytes/sec in PIO mode and 13 MBytes/sec in Fast Multiword DMA mode. Drives for SCSI bus support transfer rates of 10 MBytes/sec in synchronous mode. In these drives, a conventional 64K.times.16 DRAM (part # TC511664) is used for local buffer RAM where 32K bytes of the RAM is used to store code used by the microcontroller.
As mentioned earlier and also evidenced by the performance of these drives, the conventional memories can not meet the requirements of a cost effective high performance storage subsystem.
A major improvement can be made if the microcontroller access and the access coupled through a buffer controller from other independent utilization devices (such as disk interface, host interface control) are separated.
Application specific multiport memories have been developed for serial scan applications such as video display systems which combine a DRAM with an on-board Serial Access Memory (SAM).
FIG. 2 shows an application specific memory according to U.S. Pat. No. 4,541,075, by Dill et al. having a row buffer register which can transfer rows of data to and from the main memory and a second Input/Output port for accessing the row buffer register in either serial or parallel mode. A limitation of the memory device described in this patent is that only one utilization device can independently use the second I/O port. Yet another limitation of the memory device proposed by Dill et al. is that partial write or masked write (writing only to selected words) from the row buffer register to a row of the main memory is not supported. In this memory device, the partial write can be emulated by "memory row read modify write" operation which includes the steps of: transferring the row from the main memory to the row buffer register, modifying the row buffer register through the second I/O port, and transferring the row buffer register back to the row of the main memory. This "memory row read modify write" operation assumes that the data of the same row in the main memory was not changed between the read and write back. Note that data corruption will occur if during "memory row read modify write" operation, part of the data in the main memory row was modified through the first I/O port. This is a general limitation of the prior art and will be discussed in more detail below.
Utilization or peripheral devices generally access a semiconductor memory through the memory's ports. Accesses by multiple utilization devices therefore require the semiconductor memory being accessed to have multiple ports to support independent utilization device accesses. A major limitation in providing access by multiple independent utilization devices through a dedicated port per utilization device is that concurrent write to the same row of the memory by two or more utilization devices is not possible without comprimising integrity of the data. FIG. 3 shows an extension of the memory device taught by Dill et al. In this patent further having a third I/O port for accessing a second row buffer independent of the first row buffer for use by a second utilization device. FIG. 4 shows two blocks in the main memory wherein the tail end of block 1 and beginning of block 2 are in the same row of the main memory (row 2). Consider an application in which the first utilization device is using first row buffer register through second I/O port and a second utilization device is using the second row buffer register through the third I/O port; and furthermore utilization device 1 is accessing block 1, and utilization device 2 is accessing block 2. Now consider the following sequence of operations in this example: utilization device 1 reads row 2 of the memory into the first row buffer register and starts modifying the first row buffer register through the second I/O port, utilization device 2 read the same row of memory into the second row buffer register and starts modifying the second row buffer register through the third I/O port, utilization device 1 completes modifying the beginning of the row buffer register which is part of block 1 and writes it back to the row of the memory, utilization device 2 completes modifying the tail end of the second row buffer register which is part of the block 2 and writes it back to the row of the memory. It should be apparent that the last operation will then overwrite the data of block 1 which was modified by utilization device 1 and causes data corruption.
Yet another data corruption resulting from "memory row read modify write" operation unique to storage subsystem applications will be discussed next. Consider an execution of a read command by the storage subsystem during which blocks are read from the disk and disk interface (first utilization device) will be writing blocks of data to the memory, and concurrently good blocks which are buffered in the memory are read by the host interface (second utilization device). During this operation if an error occurs when a block is read from the media and transferred from disk interface to buffer, then the on-board "on the fly correction (OFC)" circuitry of the ECC will attempt to correct the correctable errors concurrent with the transfer of the next block from the disk interface. The case in which the error was located at the tail end of the blocks, which is in the same row of the memory as the beginning of the next block, will be considered. This case may use the following sequence of operations: utilization device reads the row of the memory into the first row buffer register and starts modifying the first row buffer register through the second I/O port, the OFC circuitry locates an error in the same row of the memory and corrects the error through the first I/O port, utilization device completes modifying the tail end of the row buffer register which is the beginning of block and writes it back to the row of the memory, which will then overwrite the data which was corrected by the OFC circuitry and cause data corruption.
These types of a problems, in order to be avoided, place a restriction on memory utilization such that if a subset of memory rows are dedicated for each block, which requires that either the data block to be multiple of a row size (which may not be always possible) or waste some part of the memory.
Furthermore, multiple parallel-by-bit I/O ports each coupled to a utilization device increases the number of the pins of the memory device package, which increases the cost of the memory device.
There is a need for a cost effective high performance multiport memory for block access applications such as disc drive applications that allows independent access by multiple utilization devices coupled through a buffer controller to a second parallel-by-bit I/O port.

Semiconductor memory device for mass storage block access applications


Disclosed is an alternating current dimming drive circuit for an LED, comprising a rectification unit and N stages of LED direct current drive circuits. In the ith stage of LED direct current drive circuit, a first end of the ith voltage sampling unit and an input end of the ith LED light source module directly or indirectly receive the output voltage of the rectification unit; a voltage division end of the ith voltage sampling unit is connected to a second input end of the ith switch unit; and a first input end of the ith switch unit is connected to an output end of the ith LED light source module, and an output end of the ith switch unit, a second end of the ith voltage sampling unit and a second output end of the rectification unit are grounded. When the ith switch unit is switched on, the first to the ith LED light source modules emit light. When the ith switch unit is switched off, if i is less than N, the first to the (i+1)th LED light source modules emit light, and if i is equal to N, the first to the Nth LED light source modules stop emitting light. The present invention realizes an alternating current directly-driven LED light source module and will not flicker in the case of alternating current voltage fluctuation.

LEDs, as newly emerged solid light sources, have the prospect of becoming a new generation of light source with advantages such as energy conservation, environmental protection, long service life and the like. It is known that an LED is driven by a DC voltage. However, AC power is generally supplied in daily life. Therefore, for the LED to normally emit light, a power converter is required to implement the functions of rectification and voltage reduction. Introduction of a power converter may bring about many negative effects. Firstly, service life of the power converter is far shorter than that of the LED, so service life of a light-emitting device may be shortened. Secondly, the power converter may reduce efficiency of the light-emitting device. Thirdly, in a low-power application, the power converter may cause reduction of the power factor and increase of the total harmonic current. In order to fully utilize the advantages of the LED, an LED light-emitting device directly driven by an AC power is developed.
In conventional technical solutions of LED driving, in combination with a traditional silicon-controlled dimmer, only the traditional function of luminance adjustment is considered, but the adjustability of color temperature and hue of the LED is not taken into consideration. In addition, in most of the conventional technical solutions of LEDs driven by the AC power, multiple LED components are coupled in reverse parallel or based on a topology of a rectification bridge circuit, to meet the driving requirements of the AC power. However, the AC power is subjected to fluctuation according to a specific frequency cycle. Since the LED has its own switch-on voltage, when the transient voltage exceeds the switch-on voltage, the LED may be unintentionally switched on and emit light. Otherwise, the LED may be cut-off and does not emit light. Such circuit causes low light-emitting efficiency for the LED, and in addition, when the AC voltage fluctuates, the LED may flicker.

Dimming drive circuit of alternating current directly-driven LED module


The semiconductor memory system includes a memory controller, N system data buses, and first through P-th memory module groups. The N system data buses are connected to the memory controller and respectively have a width of M/N bits. The first through P-th memory module groups are connected to the N system data buses and respectively have N memory modules. In each of the first through P-th memory module groups, a different one of the N system data buses is connected to each of the N memory modules, and each of the N system data buses has a data bus width of M/N bits. The first through P-th memory module groups are operated in response to first through P-th corresponding chip select signals. M is the bit-width of an entire system data bus of the semiconductor memory system. The N system data buses are wired such that data transmission times are the same from each N memory modules that operate in response to the same chip select signal to the memory controller.

1. Field of the Invention
The present invention generally relates to the field of semiconductor memory systems, and more particularly, the present invention relates to a semiconductor memory system having multiple system data buses.
A claim of priority is made to Korean Patent Application No. 2002-50172, filed on Aug. 23, 2002, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
2. Description of the Related Art
Memory devices have been developed with emphasis on the realization of high degrees of integration and large memory capacities. Central processing units (CPUs), on the other hand, have been developed with emphasis on achieving high processing speeds. As a result, the difference in operating speeds between CPUs and memory devices has been gradually increasing. As such, the operating speed of the computer system memory device has become a chief factor limiting the performance of the computer system itself.
FIG. 1 is a block diagram of the structure of a conventional semiconductor memory system.
A system data bus having a width of M bits connects memory modules 120, 130, 140, and 150 to a memory controller 110. The memory modules 120, 130, 140, and 150 are installed in respective memory slots (not shown). The memory modules 120, 130, 140, and 150 have the same data bus width as the system data bus. Each of the memory slots is commonly connected to the system data bus.
Also, all of the memory slots are sequentially connected to the system data bus. Thus, in large-capacity memory systems, as the number of memory slots increases, channel discontinuity in the system data bus line and impedance mismatch increase. Hence, the operating characteristics of the system data bus are deteriorated in a high frequency region, thus limiting the operation speed of the system.
Large-capacity memory devices are essential for, in particular, the operation of a high-performance, large-capacity server system. In order to maximize the capacity of a memory system, the number of memory devices installed in the memory system should be maximized. For this purpose, the number of memory slots accommodating memory modules should be increased, and the number of memory devices per memory module should be maximized.
On the other hand, for high-speed operation of the memory system, an impedance mismatch factor of the system data bus or load of the system data bus caused by the memory devices should be minimized. In order to meet these requirements for high-speed operation, both the number of memory slots connected to a channel and the number of memory modules should be small.
Thus, a conflict exists between maximizing the number of memory devices to achieve a large memory capacity and minimizing the number of memory devices to achieve a high-speed operation. It is therefore difficult to simultaneously achieve both a large memory capacity and a high-speed operation.

Semiconductor memory system having multiple system data buses


According to the invention there is provided a method of reducing wear of one or both of two steel elements having surfaces in sliding or sliding-rolling contact. The method involves applying an HPF friction control composition to one, or more than one contacting surface of one or both of the two steel elements. In a particular example, the HPF friction control composition comprises a rheological control agent, a lubricant, a friction modifier, and one, or more than one of a retentivity agent, an antioxidant, a consistency modifier, and a freezing point depressant.

The control of friction and wear of metal mechanical components that are in sliding or rolling-sliding contact is of great importance in the design and operation of many machines and mechanical systems. For example; many steel-rail and steel-wheel transportation systems including freight, passenger and mass transit systems suffer from the emission of high noise levels and extensive wear of mechanical components such as wheels, rails and other rail components such as ties. The origin of such noise emission, and the wear of mechanical components may be directly attributed to the frictional forces and behaviour that are generated between the wheel and the rail during operation of the system.
In a dynamic system wherein a wheel rolls on a rail, there is a constantly moving zone of contact. For purposes of discussion and analysis, it is convenient to treat the zone of contact as stationary while the rail and wheel move through the zone of contact. When the wheel moves through the zone of contact in exactly the same direction as the rail, the wheel is in an optimum state of rolling contact over the rail. However, because the wheel and the rail are profiled, often misaligned and subject to motions other than strict rolling, the respective velocities at which the wheel and the rail move through the zone of contact are not always the same. This is often observed when fixed-axle railcars negotiate curves wherein true rolling contact can only be maintained on both rails if the inner and the outer wheels rotate at different peripheral speeds. This is not possible on most fixed-axle railcars. Thus, under such conditions, the wheels undergo a combined rolling and sliding movement relative to the rails. Sliding movement may also arise when traction is lost on inclines thereby causing the driving wheels to slip.
The magnitude of the sliding movement is roughly dependent on the difference, expressed as a percentage, between the rail and wheel velocities at the point of contact. This percentage difference is termed creepage.
At creepage levels larger than about 1%, appreciable frictional forces are generated due to sliding, and these frictional forces result in noise and wear of components (H. Harrison, T. McCanney and J. Cotter (2000), Recent Developments in COF Measurements at the Rail/Wheel Interface, Proceedings The 5th International Conference on Contact Mechanics and Wear of Rail/Wheel Systems CM 2000 (SEIKEN Symposium No. 27), pp. 30–34, which is incorporated herein by reference). The noise emission is a result of a negative friction characteristic that is present between the wheel and the rail system. A negative friction characteristic is one wherein friction between the wheel and rail generally decreases as the creepage of the system increases in the region where the creep curve is saturated. Theoretically, noise and wear levels on wheel-rail systems may be reduced or eliminated by making the mechanical system very rigid, reducing the frictional forces between moving components to very low levels or by changing the friction characteristic from a negative to a positive one, that is by increasing friction between the rail and wheel in the region where the creep curve is saturated. Unfortunately, it is often impossible to impart greater rigidity to a mechanical system, such as in the case of a wheel and rail systems used by most trains. Alternatively, reducing the frictional forces between the wheel and the rail may greatly hamper adhesion and braking and is not always suitable for rail applications. In many situations, imparting a positive frictional characteristic between the wheel and rail is effective in reducing noise levels and wear of components.
It is also known that, wear of train wheels and rails may be accentuated by persistent to and fro movement resulting from the presence of clearances necessary to enable a train to move over a track. These effects may produce undulatory wave patterns on rail surfaces and termed corrugations. Corrugations increase noise levels beyond those for smooth rail-wheel interfaces and ultimately the problem can only be cured by grinding or machining the rail and wheel surfaces. This is both time consuming and expensive.
There are a number of lubricants known in the art and some of these are designed to reduce rail and wheel wear on rail roads and rapid transit systems. For example, U.S. Pat. No. 4,915,856 discloses a solid anti-wear, anti-friction lubricant. The product is a combination of anti-wear and anti-friction agents suspended in a solid polymeric carrier for application to the top of a rail. Friction of the carrier against the wheel activates the anti-wear and anti-friction agents. However, the product does not display a positive friction characteristic. Also, the product is a solid composition with poor retentivity.
U.S. Pat. Nos. 5,308,516, 5,173,204 and WO 90/15123 relate to solid friction modifier compositions having high and positive friction characteristics. These compositions display increased friction as a function of creepage, and comprise resins to impart the solid consistency of these formulations. The resins employed included amine and polyamide epoxy resins, polyurethane, polyester, polyethylene or polypropylene resins. However, these require continuous application in a closed loop system for optimal performance.
European Patent application 0 372 559 relates to solid coating compositions for lubrication which are capable of providing an optimum friction coefficient to places where it is applied, and at the same time are capable of lowering abrasion loss. However, the compositions do not have positive friction characteristics. Furthermore, there is no indication that these compositions are optimized for durability or retentivity on the surfaces to which they are applied.
There are several drawbacks associated with the use of compositions of the prior art, including solid stick compositions. First, outfitting railcars with friction modifier stick compositions and applying to large stretches of rail is wasteful if a noise problem exists at only a few specific locations on a track. Second, some railroads have a maintenance cycle that may last as long as 120 days. There is currently no stick technology that will allow solid lubricant or friction modifiers to last this period of time. Third, freight practice in North America is for freight cars to become separated all over the continent, therefore friction modifier sticks are required on many if not all rail cars which would be expensive and impractical. Similarly, top of rail friction management using solid sticks requires a closed system to achieve adequate buildup of the friction modifier product on the rail. A closed system is one where there is essentially a captive fleet without external trains entering or leaving the system. While city transit systems are typically closed, freight systems are typically open with widespread interchange of cars. In such a system, solid stick technology may be less practical.
As many lubricant compositions of the prior art are either formulated into solid sticks or are viscous liquids (pastes), they may not be applied to sliding and rolling-sliding systems as an atomized spray. The application of a liquid friction control composition in an atomized spray, in many instances reduces the amount of the composition to be applied to a rail system and provides for a more even distribution of the friction modifier composition at the required site. Furthermore, atomized sprays dry rapidly which may lead to minimizing the potential for undesired locomotive wheel slip.
Applying liquid-based compositions to the top of the rail, or to rail car wheels has distinct advantages over using a solid stick delivery system applied to the wheels. Using a liquid system allows for site-specific application via a hirail, wayside or onboard system. Such specific application is not possible with the solid delivery system that continually applies product to the wheels. Furthermore the low transference rate of the solid stick application method will not yield any benefits until the track is fully conditioned. This is an unlikely situation for a Class 1 rail line due to the extensive amount of track that must be covered and the presence of rail cars not possessing the solid stick lubricant. Liquid systems avoid this problem as the product is applied to the top of the rail, allowing all axles of the train to come in contact with, and benefit immediately from the product. However, this is not always true as the ability of the applied film to remain adhered to the rail and provide friction control is limited. Under certain conditions liquid products have worn off before a single train pass.
WO 98/13445 (which is incorporated by reference) describes several water-based compositions exhibiting a range of frictional compositions including positive frictional characteristics between two steel bodies in rolling-sliding contact. While exhibiting several desirous properties relating to frictional control, these composition exhibit low retentivity, and do not remain associated with the rail for long periods of time, requiring repeated application for optimized performance. Also, as these compositions are water-based, the lower limit of the temperature range within which they can be used is limited. These compositions are useful for specific applications, however, for optimized performance repeated re-application is required, and there is an associated increase in cost. Furthermore, due to several of the characteristics of these liquid compositions, these compositions have been found to be unsuitable for atomized spray applications. WO 02/26919 (which is incorporated by reference), also discloses water-based friction control agents that comprise retentivity agents to extend the beneficial properties of the composition on a steel surface.
U.S. Pat. Nos. 6,387,854 and 5,492,642 disclose water-based lubricating compositions comprising a polyoxyalkylene glycol lubricant having a MW of about 2,500, a polyoxyalkylene glycol thickener having a MW of about 12,000, and a solvent (e.g. propylene glycol). The disclosed compositions in U.S. Pat. Nos. 6,387,854 and 5,492,642 do not, however, have positive friction characteristics. These materials are pure lubricants as distinguished from friction modifiers,for example, HPF compositions, as described herein. If applied to the top of the rail, these types of lubricants require sophisticated, complicated and expensive control systems to avoid problems of wheel slip or braking. True friction modifiers, as described herein, do not require this type of application control.
The deleterious effect of high lateral forces in curves is of increasing interest in heavy haul. Although quantitative relationships are hard to come by, it is understood that high lateral forces are a significant factor in accelerated track structure degradation, rail wear, and rail rollover derailments. Lateral forces depend on the coefficient of friction (COF) at the wheel-rail interface, train handling, track geometry, steering ability of rail car trucks, and wheel/rail profiling (D. Creggar, Seventh Annual Advanced Rail Management Rail/Wheel Interface Seminar, Chicago May 2000). As railroads reduce costs and improve efficiency, top of rail friction control has emerged as a viable option for controlling lateral forces, representing an alternative approach to reducing the stress state of the railroad and associated track structure degradation. Instead of continual investment in the upgrade and strengthening of track components to better accommodate lateral train force, this technology can mitigate these forces through improved friction management at the wheel-rail interface.
The present invention provides a method of reducing wear of one or both of two steel elements having surfaces in sliding or sliding-rolling contact, in particular, a railcar wheel and a rail, which are in sliding or sliding-rolling contact. The method comprises applying a high and positive (HPF) friction control composition to one, or more than one surface of one or both of the two steel surfaces.
It is an object of the present invention to overcome drawbacks of the prior art. The above object is met by a combination of the features of the main claims. The sub claims disclose further advantageous embodiments of the invention.

This patent is subject to a terminal disclaimer.

Method for reducing wear of steel elements in sliding-rolling contact


In the case of a process for measuring the distance between a motor vehicle and an object, in the vehicle, in the case of a short distance of the object, the output signals of a first measuring device with a corresponding measuring range and, in the case of a longer distance of the object, the output signals of a second measuring device with a correspondingly longer measuring range are taken into account in a dominating manner. The measuring devices are constructed as analysis devices. The output signal of a single receiver for a single distance generator is supplied to the analysis devices as an input signal. The analysis devices analyze this input signal via an analysis process which is characteristic of the shorter or the longer distance range.

This application claims the priority of German Application No. 196 24 043.3, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a measuring process as known from U.S. Pat. No. 4,026,654. In the case of the known process, two measuring devices are provided which are completely independent of one another and may operate, for example, on a different basis. Thus, the measuring device for a short distance range may operate on an ultrasound basis and the measuring device for a longer distance range may operate on a radar or laser basis.
There is therefore needed a simplified measuring process of the above-mentioned type to the extent that the measuring equipment required for this purpose is simplified.
These needs are met according to the present invention by process for measuring the distance between a motor vehicle and an object, in which, in the vehicle, in the case of a short distance to the object, the output signals of a first measuring device with a corresponding measuring range and, in the case of a longer distance to the object, the output signals of a second measuring device with a corresponding larger measuring range are taken into account in a dominating manner. The measuring devices are constructed as analysis devices. The output signal of a single receiver for a single distance generator is fed to the analysis devices as an input signal. The analysis devices analyze this input signal via an analysis process characteristic of the short distance range or of the long distance range.
According to the present invention, only a single sensor is required which scans the whole distance range. The sensor can operate on a laser or radar basis. The use of ultrasound should, as a rule, be eliminated when a distance range is involved which on the whole is relatively long and measures more than ten meters.
The sensor emits a test signal, preferably a periodically repeated frequency-modulated continuous wave radar signal (FMCW). The signals reflected by an object are received by a single receiver and fed to the two analysis devices. There, the input signal is treated by means of analyzing processes which are characteristic of the respective distance range.
The output signal of the two analysis devices is weighted differently corresponding to the respective distance of the measuring range.
The analysis processes for the respective measuring ranges can have different designs. Having a particularly good resolution precision, a correlation process is suitable for the short distance range. In this case, the reflected signal is correlated with a reference signal; for example, is subjected to an auto correlation and the distance of the respective object is determined in this manner. Alternatively, the analysis process can be a spectral analysis process according to a Fast Fourier Transform (FFT) process using a signal delay line.
For the longer distance range, different measuring processes are also known. In tests, the use of a spectral analysis was found to be particularly advantageous. In this case, a radar signal is modulated in the transmission frequency in a suitable manner, for example, in a saw tooth shape or a triangular shape and, from the frequency shift, the distance is determined by means of a spectral analysis. It is also possible to determine the distance by the transit time of a radar pulse which is frequency-modulated during its emission.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

Process for measuring the distance between a motor vehicle and an object

Bayerische Motoren Werke Aktiengesellschaft


A pressure sensor includes a liquid crystal positioned between transparent, electrically conductive films (18 and 20), that are biased by a voltage (V) which induces an electric field (E) that causes the liquid crystal to assume a first state of orientation. Application of pressure (P) to a flexible, transparent film (24) causes the conductive film (20) to move closer to or farther from the conductive film (18), thereby causing a change in the electric field (E'(P)) which causes the liquid crystal to assume a second state of orientation. Polarized light (P.sub.1) is directed into the liquid crystal and transmitted or reflected to an analyzer (A or 30). Changes in the state of orientation of the liquid crystal induced by applied pressure (P) result in a different light intensity being detected at the analyzer (A or 30) as a function of the applied pressure (P). In particular embodiments, the liquid crystal is present as droplets (10) in a polymer matrix (12) or in cells (14) in a polymeric or dielectric grid (16) material in the form of a layer (13) between the electrically conductive films (18 and 20). The liquid crystal fills the open wells in the polymer matrix (12) or grid (16) only partially.

1. Field of the Invention
The invention is generally related to pressure sensors and, more particularly, to a new kind of pressure sensor which utilizes a combination of an electric component that includes spaced apart conductive films with a liquid crystal therebetween and an optical component which includes a polarized light transmission scheme that operates in conjunction with the liquid crystal.
2. Description of the Prior Art
Pressure is defined as force per unit area. Precise knowledge of the pressure on a system is required in a number of situations. For example, in any system which involves fluid-dynamics (e.g., oil rigs, air conditioning equipment, etc.), monitoring and control of differential pressure is essential. Pressure is one of the fundamental terms in the ideal gas law and its corollaries and is one of the determining factors in vapor-liquid equilibria. In semiconductor manufacturing, many fabrication processes are performed under vacuum pressure (e.g., plasma etching, etc.) and knowledge and control of the pressure in these processes is absolutely required. Pressure often plays an important role in the safety and performance of a system or element (e.g., point of failure, etc.).
Over the years, many different sensors have been devised for measuring pressure. For example, diaphragm elements have been used as pressure sensors wherein a thin flexible disk is connected to an indicator pointer, recorder pen, or other element. Deflection of the diaphragm due to pressure from an impinging fluid or other source causes the indicator pointer, recorder pen, or other element to move on scale which is related to pressure. Diaphragm capsules are used in a similar pressure measurement scheme and include two or more circular diaphragms welded at the edges. An inverted bell pressure sensing device includes two inverted bells in an oil bath suspended on opposite ends of a balance beam. Movement of the balance beam due to different pressures under the two bells is coupled to an attached pointer or other indicating device which is scaled to correlate with pressure. A Bourdon tube pressure sensor includes a tube with a sealed end and an open end which is connected to a fluid pressure source. The tube is typically spiral shaped, helix shaped or a C-type. Rotating motion of the tube under the operating pressure actuates a pointer or other indicator that corresponds with a pressure scale. Piezoresistive transducers convert a change in pressure into a change in resistance. These type of pressure sensors are typically silicon wafers or chips with embedded resistors. Strain on the embedded resistor caused by a source of pressure on the silicon substrate results in a linear change in resistance that is measured and converted to pressure units. Piezoelectric pressure sensing devices are based on the principle that quartz, when properly cut and oriented with respect to its crystallographic axes, generates a small electric charge on certain surfaces when stressed. In practice, a stack of piezoelectric elements are coupled to a diaphragm element, such that deflection of the diaphragm under the influence of a pressure source results in a compressive force on the quartz stack which, in turn, generates a charge proportional to the stack.
The quantitative measurement of local and global pressure on a surface is important in many applications. For example, local and global pressure measurements are particularly required in a flow field on the walls of an object in aerodynamic testing. Conventional techniques of pressure measurement in such applications generally fall in two categories. First, pressure measurements can be performed where calibration of the device is independent of the flow. Second, pressure measurements can be performed where calibration of the device in terms of the law of the wall is necessary. Pressure sensors utilizing capacitance gauges, magnin wires, etc., can be calibrated against dead weights, and are exemplary of the first category of pressure measurement. Pressure scanners and Preston tubes rely on the basic Newtonian relations and thus produce results which are unreliable and difficult to interpret in a disturbed and/or under dynamic boundary layer conditions. Pressure sensitive paints, apart from having slow response controlled by diffusion times (on the order of a few seconds), suffer similarly from the requirement of an oxygen environment which is undesirable in some working situations and also have repeatability problems. Moreover, for local pressure measurements, there are practical limitations in microsizing most available sensors. Also, when sensors need to be mounted within the body of the surface being monitored, there are limitations on the area of measurements. In view of this, there is a clear need for development of pressure sensors capable of measuring local as well as global pressures on a continuous basis which are easy to mount and cost effective.


Reading a plurality of consecutive entries and writing a plurality of consecutive entries with only one read address and one write address using a 2Read/2Write register file is provided. In one exemplary embodiment, a 64 entry register file array is partitioned into four sub-arrays. Each sub-array contains sixteen entries having one or more 2Read/2Write SRAM cells. A mechanism to write the consecutive entries by only having a 4 to 16 decode of one address is also provided. In addition, a mechanism for reading data from the register file array using a starting read word address and two read word lines generated based on the starting read word address is provided. The two read word lines are used to access the two read ports of the entries in the sub-arrays.

1. Technical Field
The present invention relates generally to an improved data processing system and method. More specifically, the present invention provides an apparatus and method for providing multiple reads/writes using a 2Read/2Write register file array.
2. Description of Related Art
The basic structure of a conventional computer system includes one or more processing units connected to various input/output devices for the user interface (such as a display monitor, keyboard and graphical pointing device), a permanent memory device (such as a hard disk, or a floppy diskette) for storing the computer's operating system and user programs, and a temporary memory device (such as random access memory or RAM) that is used by the processor(s) in carrying out program instructions. The evolution of computer processor architectures has transitioned from the now widely-accepted reduced instruction set computing (RISC) configurations, to so-called superscalar computer architectures, wherein multiple and concurrently operable execution units within the processor are integrated through a plurality of registers and control mechanisms.
An illustrative embodiment of a conventional processing unit is shown in FIG. 1, which depicts the architecture for a PowerPC™ microprocessor 12 manufactured by International Business Machines Corporation. Microprocessor 12 operates according to reduced instruction set computing (RISC) and is a single integrated circuit superscalar microprocessor. The system bus 20 is connected to a bus interface unit (BIU) of microprocessor 12. Bus 20, as well as various other connections described, include more than one line or wire, e.g., the bus could be a 32-bit bus.
BIU 30 is connected to an instruction cache 32 and a data cache 34. The output of instruction cache 32 is connected to a sequencer unit 36. In response to the particular instructions received from instruction cache 32, sequencer unit 36 outputs instructions to other execution circuitry of microprocessor 12, including six execution units, namely, a branch unit 38, a fixed-point unit A (FXUA) 40, a fixed-point unit B (FXUB) 42, a complex fixed-point unit (CFXU) 44, a load/store unit (LSU) 46, and a floating-point unit (FPU) 48.
The inputs of FXUA 40, FXUB 42, CFXU 44 and LSU 46 also receive source operand information from general-purpose registers (GPRs) 50 and fixed-point rename buffers 52. The outputs of FXUA 40, FXUB 42, CFXU 44 and LSU 46 send destination operand information for storage at selected entries in fixed-point rename buffers 52. CFXU 44 further has an input and an output connected to special-purpose registers (SPRs) 54 for receiving and sending source operand information and destination operand information, respectively. An input of FPU 48 receives source operand information from floating-point registers (FPRs) 56 and floating-point rename buffers 58. The output of FPU 48 sends destination operand information to selected entries in rename buffers 58.
Microprocessor 12 may include other registers, such as configuration registers, memory management registers, exception handling registers, and miscellaneous registers, which are not shown. Microprocessor 12 carries out program instructions from a user application or the operating system, by routing the instructions and data to the appropriate execution units, buffers and registers, and by sending the resulting output to the system memory device (RAM), or to some output device such as a display console.
A high-level schematic diagram of a typical general-purpose register 50 is further shown in FIG. 2. GPR 50 has a block 60 labeled "MEMORY_ARRAY—80×64," representing a register file with 80 entries, each entry being a 64-bit wide word. Blocks 62a (WR0_DEC) through 62d (WR3_DEC) depict address decoders for each of the four write ports 64a-64d. For example, decoder 62a (WR0_DEC, or port 0) receives the 7-bit write address wr0_addr<0:6> (write port 64a). The 7-bit write address for each write port is decoded into 80 select signals (wr0_sel<0:79> through wr3_sel<0:79>). Write data inputs 66a-66d (wr0_data<0:63> through wr3_data<0:63>) are 64-bit wide data words belonging to ports 0 through 3 respectively. The corresponding select line 68a-68d for each port (wr0_sel<0:79> through wr3_sel<0:79>) selects the corresponding 64-bit entry inside array 60 where the data word is stored.
There are five read ports in this particular prior art GPR. Read ports 70a-70e (0 through 4) are accessed through read decoders 72a-72e (RD0_DEC through RD4_DEC), respectively. Select lines 74a-74e (rd0_sel<0:79> through rd4_sel<0:79>) for each decoder are generated as described for the write address decoders above. Read data for each port 76a-76e (rd0_data<0:63> through rd4_data<0:63>) follows the same format as the write data. The data to be read is driven by the content of the entry selected by the corresponding read select line.
Register files, such as the one described above, are a common type of storage circuitry used in modern day state-of-the-art microprocessors. For example, in a high performance processor application, in order to maximize the number of instructions executed concurrently and to provide high bandwidth to the instruction cache, a large register file, e.g., an instruction buffer (IBUF) supporting multiple simultaneous reads and writes is required. However, large register file arrays having multiple simultaneous reads and writes require a large SRAM cell area to support several read and write ports and a complex decoding scheme. The result is slow access and large register file array area. Therefore, it would be beneficial to have an improved apparatus and method for providing a multiple read/write register file in which area and access time is minimized.

Method for providing multiple reads/writes using a 2read/2write register file array


A current detector circuit for detecting a load current flowing through a load includes a first series circuit having a first element and the load connected in series, a second series circuit having a second element and a resistor connected in series, the second element having a temperature characteristic equal to the temperature characteristic of the resistance of the first element, a power supply configured to supply voltage to the first series circuit and the second series circuit, and a control circuit configured to control the voltage drop across the second element so that the voltage drop across the second element is equal to the voltage drop across the first element. A current detection signal corresponding to the load current is generated based on a current flowing through the second element.

1. Technical Field
This disclosure relates generally to current detector circuit technology, and more particularly to a current detector circuit having excellent temperature characteristics and a current-mode DC-DC converter using the same.
2. Description of the Related Art
FIG. 1 is a diagram showing a conventional current detector circuit that detects a current flowing through a switching device M11 at the output stage of a step-down DC-DC converter.
In this conventional case, a series circuit of a resistor Rs and a PMOS transistor M12 is connected in parallel to the switching device M11 using a PMOS transistor. Further, the gates of the switching device M11 and the PMOS transistor M12 are connected in common.
The switching device M11 and the PMOS transistor M12 are connected to ground through an NMOS transistor M16. One end of the NMOS transistor M16 is grounded, and the output voltage Vout of the DC-DC converter through a smoothing circuit formed of an inductor L1 and a capacitor C1 is extracted from the other end of the NMOS transistor M16.
A signal P applied to the gates of the switching device M11 and the PMOS transistor M12 and a signal N applied to the gate of the NMOS transistor M16 are complementary to each other. A current detection signal Vsense is extracted from the connection node of the resistor Rs and the PMOS transistor M12. The above-described complementary signals P and N are generated based on this current detection signal Vsense.
The current detection signal Vsense in this circuit is expressed as follows:Vsense=IL·Rm1on·Rs/(Rm1on+Rm2on+Rs),  (1)where IL is a load current, Rm1on is the ON-resistance of the switching device M11, and Rm2on is the ON-resistance of the PMOS transistor M12.
Normally, MOS transistors have temperature coefficients greater than that of the resistor Rs formed of a diffused resistor or the like. Therefore, Eq. (1) is rewritten into an equation in consideration of temperature, which is expressed as follows:Vsense=IL·Rm1on(1+Δt·γ)·Rs/(Rm1on(1+Δt·γ)+Rm2on(1+Δt·γ)+Rs),  (2)where Δt is a change in temperature, γ is the temperature coefficient of the ON-resistance of each MOS transistor, and the temperature coefficient of the resistor Rs is 0.
Dividing each of the numerator and the denominator of Eq. (2) by (1+Δt·γ) results in:Vsense=IL·Rm1on·Rs/(Rm1on+Rm2on+Rs/(1+Δt·γ)),  (3)thus leaving the term (1+Δt·γ) showing temperature dependence in the equation. This shows that the current detection signal Vsense has temperature dependence. Therefore, temperature compensation is necessary in current detector circuits having circuit configurations as described above.
FIG. 2 is a diagram showing a current detector circuit disclosed in Japanese Laid-Open Patent Application No. 2000-307402.
As shown in FIG. 2, in this current detector circuit, a series circuit of an NMOS transistor M22, the resistor Rs, and a heat-sensitive element 5 is connected in parallel to an NMOS transistor M21, so that temperature compensation of the NMOS transistor M21 is performed with the heat-sensitive element 5.
The current detection signal Vsense is output from the connection node of the resistor Rs and the heat-sensitive element 5. A thermistor, diode, or MOS transistor is employed as the heat-sensitive element 5.
FIG. 3 is a diagram showing an overcurrent protection circuit disclosed in Japanese Laid-Open Patent Application No. 2002-26707.
As shown in FIG. 3, in this overcurrent protection circuit, a series circuit of an NMOS transistor M32 and the resistor Rs is connected in parallel to an NMOS transistor M31, so that the current flowing through a load element 20 branches into a current Id1 and a current Id2. The gates of the NMOS transistors M31 and M32 are connected to a gate drive circuit 50.
In FIG. 3, a series circuit of diodes 32 is a first constant voltage power supply having temperature dependence, and Vref1 denotes a second constant voltage power supply having very little temperature dependence. The voltage difference between the first and second constant voltage power supplies is amplified in an operational amplifier circuit 31 to generate a temperature-dependent reference voltage, and the generated reference voltage is applied to one input of a comparator 34.
The current detection signal Vsense, which is the voltage drop across the resistor Rs, is applied to the other input of the comparator 34. The NMOS transistors M31 and M32 and the series circuit of multiple diodes 32 are integrated onto a same semiconductor substrate 30. The output of the comparator 34 is input to the gate drive circuit 50.
According to the above-described configuration, this overcurrent protection circuit compensates for the temperature characteristics of the ON-resistances of the NMOS transistors M31 and M32 with the temperature characteristics of the first constant voltage power supply 32 formed of diodes.
In the case of detecting a detection current that changes with temperature by converting the detection current into voltage with a resistor having little temperature dependence, the detection signal has temperature dependence. Therefore, in the above-described conventional techniques, a component having opposite temperature characteristics (a heat-sensitive element such as a diode, thermistor, or MOS transistor) is added in order to compensate for the temperature dependence.
However, according to the above-described conventional techniques, a device used in the current detector circuit (an NMOS transistor in the above-described conventional techniques) and an element used for temperature compensation (a heat-sensitive element such as a diode, thermistor, or MOS transistor) are different, thus causing a problem in that complete temperature compensation cannot be performed.

Current detector circuit and current-mode DC-DC converter using same


An appliance for supporting a woman during childbirth includes a flexible supporting part of flat design for supporting the woman's back, buttocks and thighs. Attached to the supporting part are suspension elements by means of which the supporting part can be suspended. The supporting part preferably has a basic shape in the form of an elongate quadrilateral, with two longitudinal sides, a head side and a leg side. The leg side is bent in or recessed thereby forming two tabs which are intended for supporting the thighs and between which the child-bearing region in the vicinity of the woman's vagina remains freely accessible. By adjusting the suspension height of the head side or leg side, the position of the supporting part and therefore the woman's position can be selected, any position from an upright posture to a supine position being possible.

The invention relates to an appliance for supporting a woman during childbirth.
As is known, women in childbirth are nowadays supported almost exclusively in the lying position. However, experts have repeatedly pointed out, more recently with greater force, that the supine position is for the child-bearing woman a questionable and disadvantageous position which entails a number of considerable disadvantages in the course of the birth process and which, moreover, in no way corresponds to the natural position.
The preference for the lying child-bearing position is without doubt due, on the one hand, to the development of clinical obstetrics in the past few decades. But on the other hand, there is also a lack of appliances, by means of which a child-bearing woman can be supported suitably and comfortably in an upright child-bearing posture in accordance with current medical requirements. Furthermore, an appliance allowing an upright child-bearing posture must at the same time also permit a lying position, if necessary, for example for a surgical operation when complications occur.

Appliance for supporting women during childbirth


Using a combination of auto-correlation and cross-correlation techniques provides a symbol timing recovery in a Wireless Local Area Network (WLAN) environment that is extremely robust to wireless channel impairments such as noise, multi-path and carrier frequency offset. An auto-correlator provides an estimate for a symbol boundary, and a cross-correlator is subsequently used to more precisely identify the symbol boundary. Peak processing of the cross-correlation results provides further refinement in symbol boundary detection. In receiving a packet conforming to the IEEE 802.11a standard, the method requires a minimum of only three short symbols of the 802.11a short preamble to determine timing, and guarantees timing lock within the duration of the 802.11a short preamble. This method and system can be easily applied to any other preamble based system such as 802.11g and High Performance Radio LAN/2 (HIPERLAN/2).

The IEEE standard 802.11a pertains to wireless local area networks (WLAN), and adopts Orthogonal Frequency Division Multiplexing (OFDM). OFDM is a technology that transmits data as multiple signals simultaneously over a single transmission path. OFDM spreads the data over a large number of carriers that are spaced apart at precise frequencies. Typically, a transmitter transforms frequency based data into the time-domain using an Inverse Fast Fourier Transform (IFFT) algorithm prior to transmission. A receiver then transforms a received packet back to the frequency domain using a Fast Fourier Transform (FFT) algorithm. The total number of sub-carriers translates into the number of points of the IFFT/FFT. In a wireless networking environment, OFDM has inherent advantages over a signal carrier system in a frequency-selective fading channel, such as high spectral efficiency, resiliency to RF interference, and lower multi-path distortion.
The IEEE 802.11 standard defines both an ad-hoc wireless network configuration and an infrastructure wireless network configuration that comprise a Basic Service Set (BSS). The ad-hoc configuration operates in a peer-to-peer mode that enables mobile stations to connect to each other directly, without the use of an access point. The infrastructure network configuration uses access points that bridge individual mobile stations with a wired network. Thus, receivers can be located at either individual mobile stations, or at access points to the network.
Under 802.11a, packets are mapped into a framing format suitable for sending and receiving user data and management information between two or more stations. This format includes a preamble field that includes a short preamble and a long preamble. The short preamble consists of 10 repetitions of a 16 sample short training symbol. The short preamble is used for received signal strength intensity (RSSI), automatic gain control (AGC), and coarse frequency synchronization. Subsequent to the preambles are a signal field, followed by multiple data fields. It is of critical importance to determine field boundaries as soon as possible in order to avoid a mismatch when processing the packet, and consequently, to avoid loss of the packet.
Two alternate methods of correlation have been used in connection with the preambles to determine field boundaries. An auto-correlation of the received signal involves correlating the signal with a delayed version of itself with the length of the correlation window equal to the length of a short symbol. When using an auto-correlation, a correlation plateau occurs due to the periodic nature of the short preamble. One approach to timing recovery is to look for the end of the correlation plateau in order to determine the field boundary.
A second approach uses a cross-correlation (or matched filter) between the received signal and the known values of the short symbol. Because the short preamble consists of 10 repetitions of a 16 sample training symbol, when the incoming data stream is correlated with the preamble, ideally the cross-correlation generates a peak every 16 samples, for a total of 10 peaks. This second approach looks to the last peak to identify the field boundary.

Method and system for fast timing recovery for preamble based transmission systems


An apparatus for photographing an image of a sample observed through a microscope comprises a photometry region designating unit, an optical member for superimposing an image of an indicator light beam on an image of an object light beam, an area sensor, a reflecting member for reflecting the object light beam and the indicator light beam and guiding them to the area sensor, a photometry region determining unit, a photometry unit, and a photographing unit. The photometry region designating unit generates an indicator light beam which is movable in a plane perpendicular to the optical axis of the object light beam output from an objective lens. The photometry region determining unit stores a photometry signal supplied from the area sensor in correspondence with a position of a light receiving plane, detects the position of the light receiving plane, on which the indicator light is projected, by using the photometry signal, and determines a photometry region based on the detected position. The photometry unit measures the brightness of the photometry region determined by the photometry region determining unit and calculates a photometry value. The photographing unit photographs an image of the sample based on the photometry value.

1. Field of the Invention
The present invention relates to a microphotographing apparatus which can photograph a sample observed through an eyepiece of a microscope, and more particularly to improvement of photometry for measuring the brightness of a desired portion of an object to be photographed.
2. Description of the Related Art
Generally known is a fluorescence microscope for observing a fluorescent sample of a protein or gene in which a fluorescent marker is added to an organic tissue or cell.
Recently, by a phase contrast microphotography or a differential interfere microphotography, or the combination thereof, it have been possible to stain a substance having only minute fluorescence in multicolor so as to accurately detect the positional relationship between the substance and another substance or to observe where the fluorescent colored substance is located in the cell structure.
In many cases of the above-mentioned fluorescent observation, a fluorescent portion is present in a limited portion of a dark background. To photograph such a fluorescent portion, it is necessary to measure the brightness of the image to be photographed in order to determine the exposure time.
According to the conventional photometry, an exposure time is determined on the basis of an average brightness in the field of a microscope. This method has a drawback that the fluorescent portion is lost in the photographed image.
To overcome this drawback, for example, Published Unexamined Japanese Patent Application (PUJPA) No. 58-214121 proposes an apparatus for observing a photometry region (a region the brightness of which is to be measured) through an eyepiece of a microscope, measuring the brightness of a desired portion of the observed portion, and determining the exposure time on the basis of the brightness data on the photometry region.
FIG. 10 shows an optical system of the microphotographing apparatus disclosed in the above mentioned application. A light beam is applied through a objective lens 1 to a first surface S1 of a quadrilateral prism 2, and output from a second surface S2 of the prism 2, which is parallel to the first surface S1. The light beam is reflected by first to third reflecting members Ml to M3 in sequence. The beam reflected by the third reflecting member M3 is incident on a third surface S3 of the quadrilateral prism 2 and output through a fourth surface S4 thereof. Then, the beam is guided to an eyepiece 3.
A reticle R for focusing the beam on an object and a photometry member 4 having a inclined semi-transparent portion for reflecting the beam are arranged between the second and third reflecting members M2 and M3. With this arrangement, an intermediate image Il is formed on the reticle R.
A relay lens 5 is provided on the outgoing side of the photometry member 4, so that the intermediate image Il formed on the reticle R is re-formed as an object image I2 before the eyepiece 3.
In the above-described optical system, the photometry member 4 (i.e. photometry prism) having a semi-transparent plane, which reflects a portion of the light beam corresponding to a photometry region, is movable with respect to the optical axis. By virtue of the photometry member 4, an indicator image indicating the photometry region is projected on the object image observed through the eyepiece 3 The indicator image is movable to a desired position on the object image by moving the photometry member 4 in a plane perpendicular to the optical axis.
The image in which the photometry region is designated is extracted from, for example, a first reflecting member Ml, to determine the exposure time. When the image is photographed, the second reflecting member M2 is removed from the light path, an intermediate image I3 is formed on a film via a relay lens 6 and a shutter 7 is controlled in accordance with the exposure time.
However, in the above photographing apparatus, an intermediate image Il is formed in the observing optical system and the reticle R for indicating a photometry region and the range of a photograph is provided in the observing optical system and the photographing optical system so that the user can observe the photometry region and the range of a photograph. For this reason, the relay lenses 5 and 6 are required for relaying the intermediate images 11 and 13, with the result that an observed image and a photographed image are degraded.

Microscope using photographing unit and photometer


In order to facilitate and make more ergonomic the drilling of a multitude of holes in workpieces, particularly in the assembly of large scale components, such as an aircraft body, the power drill is docked to a support by an attachment which engages and locks onto a guide bushing or bore in the support. The attachment assures that the drill bit is precisely axially aligned with a hole to be drilled. The feed advance is performed by a leveraged action controlled by the operator. The leverage can be provided, for example by a Bowden pull cable. The attachment reduces the exertion to be made by the operator, thereby avoiding ergonomically unsatisfactory work positions.

In the production of certain large scale components each including a plurality of structural elements, a multitude of rivet holes are required for connecting the structural elements by rivets particularly in the production of aircraft components. Manually operated power tools such as power drills are hard to hold in a precise position while simultaneously assuring a proper feed advance during the drilling, for example in the assembly of an aircraft body or other large scale components. The difficulties in precisely holding a power drill are aggravated when the different drilling positions are hard to access and/or when the tools or power tools are rather heavy, whereby operating such tools without any aids becomes rather fatiguing. Thus, this type of work requires substantial strength on the part of the worker and frequently limits of a worker's capacities are reached, which is ergonomically not desirable. Another disadvantage in connection with freely handheld power drills is seen in that it is very difficult to constantly hold the tool or drill bit in a precisely axially aligned position relative to the hole to be drilled perpendicularly to the surface of the workpiece such as a panel. However, a precisely drilled hole perpendicularly to the panel surface is required for meeting quality standards. Moreover, the feed advance force that must be applied by the worker must maintain the precise tool position during each drilling operation. These requirements are problematic, particularly where the drilling location is hard to access.

Power drill attachment and method for using the attachment