This invention discloses an improved semiconductor power device includes a plurality of power transistor cells wherein each cell further includes a planar gate padded by a gate oxide layer disposed on top of a drift layer constituting an upper layer of a semiconductor substrate wherein the planar gate further constituting a split gate including a gap opened in a gate layer whereby the a total surface area of the gate is reduced. The transistor cell further includes a JFET (junction field effect transistor) diffusion region disposed in the drift layer below the gap of the gate layer wherein the JFET diffusion region having a higher dopant concentration than the drift region for reducing a channel resistance of the semiconductor power device. The transistor cell further includes a shallow surface doped regions disposed near a top surface of the drift layer under the gate adjacent to the JFET diffusion region wherein the shallow surface doped region having a dopant concentration lower than the JFET diffusion region and higher than the drift layer.

1. Field of the Invention
The invention relates generally to the semiconductor power devices. More particularly, this invention relates to new device configurations and manufacturing method for a metal oxide semiconductor field effect transistor (MOSFET) device with planar split gate structure to improve device performance.
2. Description of the Prior Art
Even though a semiconductor power device with planar gate structure is more compatible with multiple foundries and can be produced at a lower production cost, however, conventional technologies for manufacturing a metal oxide semiconductor field effect transistor (MOSFET) device with planar gates are still challenged by several technical difficulties and limitations. Specifically, the DMOS process produces a channel with uneven channel doping density as shown in FIG. 1D such that precision control of threshold is difficult and the device is susceptible to punch-through. As shown in FIG. 1D, the channel has a peak doping level near the source region that determines the threshold. The doping level drops sharply as the channel extends into the drift region. This channel dopant profile has some problems. First, the extent of source and body diffusion affects the peak channel doping level therefore precision control of gate threshold is difficult since that would require highly precision control of source and body diffusion. Second, the sharp decrease of doping level as the channel extends into the drift region causes dramatically reduction of the charge level in this region therefore the device is vulnerable to punch-through. Furthermore, a MOSFET device that requires a reduced capacitance for high frequency applications is still limited by a high capacitance (Cgd) at low bias due to the overlap of the planar gate over the drain region. Specifically a higher Cgd occurs due to a capacitive coupling between the planar gates and the drain across an epitaxial layer not covered with the body regions, i.e., the coupling of the planar gates to the drain across the epitaxial layer between the body regions.
A semiconductor power device usually comprises a plurality of power transistor cells in parallel. Referring to FIG. 1A for a single cell of a typical conventional vertical DMOS field effect transistor (FET) device configured with a planar structure having horizontal channel and gate, the channel is diffused from the edge of the source region near the gate. A JFET implant, e.g., a N-type dopant implant for a NMOSFET device, may be used to reduce the increase of the on-resistance caused by the lateral diffusion that pinches the drain regions between the channel regions. However, as discussed above, such device has limited high frequency applications at a low bias due to the high gate-to-drain capacitance caused by the coupling of the planar gates to drain across the epitaxial and drift regions between the body regions.
Furthermore, a DMOS device with planar gate is limited by several technical limitations that the cell pitch cannot be easily reduced. Specifically, in reducing a cell pitch of a DMOS device, a large distance between the body regions leads to a reduced breakdown voltage. On the other hand, a small distance between the body regions causes a high drain to source on-resistance Rdson. Baliga disclosed in U.S. Pat. No. 6,800,897 (issued on Oct. 5, 2005) and U.S. Pat. No. 6,791,143 (issued on Sep. 14, 2004) a SSCFET device as that shown in FIG. 1B wherein the device disclosed in the U.S. Pat. No. 6,791,143 is named as a SSCFET in a November 2003 publication where SSC stands for Silicon Semiconductor Corporation. For a n-channel MOSFET device, the SSCFET structure is implemented with retrograde N-type JFET implant region to improve device on resistance. The JFET implant region is further combined with a buried P-region to shield the gate from directly coupling to the drain as that often occurs in a conventional DMOS device. However, the SSCFET structure as shown in FIG. 1B does not provide an effective resolution to these technical difficulties due to the competing design requirements. Specifically, a high dose JFET implant for the purpose of achieving a lower resistance also compensates the P-body and the P-shield implant regions. For these reasons, the demands for high performance power device with high efficiency that is suitable for high frequency applications cannot be satisfied by the semiconductor power devices with planar gates as produced now by the conventional technologies.
In U.S. Pat. No. 6,639,276, entitled "Power MOSFET with ultra-deep base and reduced on resistance" (issued on Oct. 28, 2003), a MOSFET device is disclosed as that shown in FIG. 1C wherein the MOSFET includes a highly doped semiconductor substrate 30 to support a lightly doped epitaxial layer 31. The MOSFET device further includes highly doped source regions 33 of the same conductivity as the epitaxial layer 31 formed in respective lightly doped body regions 32 of an opposite conductivity type. The MOSFET device also includes gate insulation layers 34 formed over invertible channels 32′. The gate insulation layers 34 do not extend over the entire area of common conduction regions 35, which are located between the body regions 32. The gate insulation layers only extend over a portion of the common conduction regions 35. The insulation spacer 50 is disposed between the gate electrodes 51 and covers the remaining portions of the common conduction regions 35. The insulation spacers 50 make contact with the top surface of the epitaxial layer 31 and cover a substantial portion of each common conduction region 35. A source contact 39, which may be made from aluminum, is provided to make contact with the source regions 33 and body regions 32. Insulating sidewalls 38 and insulating top layers 37 are interposed between the gate electrodes 51 and the source contact 39 in order to insulate the two from one another. The insulating spacers 50 are drastically thickened and preferably expand over a substantial portion of the width of common conduction regions 35. The insulating spacers 50 reduce the area of the gate electrodes 51 overlying the surface of common conduction regions 35. This results in a reduced gate to drain capacitance. The MOSFET further includes deep implanted junctions 92 formed in the body of the epitaxial layer 31. The concentration of dopants in deep implanted junctions 92 may be increased. An increase in the dopant concentration of deep implanted junctions 92 allows for an increase in the dopant concentration of the common conduction region 35, which improves Rdson without sacrificing the breakdown voltage. The device shown in FIG. 1C has an improved structure over the devices as shown in FIGS. 1A and 1B. It applies a split gate configuration to reduce the gate to drain capacitance without sacrificing other performance requirements. But similar to the devices as shown in FIGS. 1A and 1B, this device is also a DMOS device that the channel 32′ is formed by double diffusion process of source region 33 and body region 32. All DMOS devices share the common channel doping profile as shown in FIG. 1D. As discussed above, the device as shown in FIG. 1C has a threshold voltage that is difficult to control and a channel that is vulnerable to punch-through.
Therefore, a need still exists in the art of power semiconductor device design and manufacture to provide new manufacturing method and device configuration in forming the power devices with planar gate such that the above discussed problems and limitations can be resolved. For those of ordinary skill the art, a planar gate MOSFET device compatible with multiple foundries is desirable for reducing production cost. It is further desirable that such devices have low capacitance at low and high bias and also has low on-resistance times a gate charge product. It is further desirable that such device being more resistant to punch-through and have a precisely controlled stable threshold voltage.

Planar split-gate high-performance MOSFET structure and manufacturing method


An apparatus is set forth including a forward and rearward support roller orthogonally and rotatably mounted upon spaced rails. The rear support roller includes a rear belt member rotatably mounted therewith and cooperative with a forward pulley. The forward pulley is fixedly mounted to a cylindrical support shaft rotatably mounted within an adapted block mounted between the forward and rear support roller upon the right frame rail. The support shaft includes a mounted bi-polar magnetic cylinder to effect resistance during rotation of the cylinder relative to the right frame rail. The cylinder includes a further cylinder adapter securable thereto to enhance magnetic attraction between the frame rail and the cylinder and further cylinder. Alternatively, a weight member may be mounted to a forward portion of the support shaft. The magnetic cylinder is also selectively mounted on a threaded shaft to space the cylinder relative to the right frame rail to vary magnetic resistance therebetween and associated resistance when an associated bicycle is mounted on the forward and rear support roller.

1. Field of the Invention
The field of invention relates to exercise apparatus, and more particularly pertains to a new and improved exercise apparatus wherein the same mounts a bicycle thereon and includes variable resistance means to vary resistance in use of the bicycle on the apparatus.
2. Description of the Prior Art
Various exercise apparatus have been utilized in the prior art to adapt and accommodate conventional bicycles onto a support structure. The support structure has utilized spaced rollers to position the rear drive wheel of the associated bicycle in a manner to effect exercise in its use while enabling utilization of the bicycle within a limited space or interior environment. Examples of the prior art include U.S. Pat. No. 4,565,365 wherein spaced rollers are mounted within a framework organization to secure a bicycle thereto in a manner consistent with the prior art.
U.S. Pat. No. 4,768,782 to Blackburn provides a further example of a prior art exercise device wherein a support framework secures an associated axle of a bicycle relative thereto to enable engagement of the tire of the bicycle with a resistance roller.
U.S. Pat. No. 4,648,597 to Adler provides a bicycle support device utilizing a vertical frame member mounting a single roller thereto with a "U" shaped support mounting the bicycle to the frame member.
U.S. Pat. No. 4,572,502 to Messineo utilizes a "U" shaped bracket member to support the spaced frame rails of an associated bicycle thereto to enable the bicycle to be maintained in a spaced relationship relative to a floor for support thereof.
U.S. Pat. No. 4,595,194 to Previtali provides a bicycle training apparatus wherein the same provides a support framework for securing the bicycle in engagement with resistance rollers as another example of a typical prior art exercise device.
As such, it may be appreciated that there is a continuing need for a new and improved exercise apparatus which addresses the problems of readily accommodating a variable resistance device to an exercise apparatus supporting a bicycle thereon and in this respect, the instant invention substantially fulfills this need.


Methods, systems, and computer readable media for detecting antenna port misconfigurations are disclosed. According to one method, the method includes storing one or more reference signal maps for identifying reference signals in downlink data in memory. The method further includes receiving downlink data that appears to be associated with a first antenna port of a device under test (DUT). The method also includes identifying, using the one or more reference signal maps, a first reference signal in the downlink data, wherein the first reference signal appears to be associated with the first antenna port. The method further includes determining, using a first computed error vector magnitude associated with the first reference signal, whether the first antenna port is misconfigured.

Long term evolution (LTE) and other radio communications technologies can require significant infrastructure and configuration. Generally, network operators test various aspects of their network equipment to ensure reliable and efficient operation. Network operators typically simulate various conditions before equipment is deployed in a live network to decrease avoidable delays and/or other problems.
Various technical specifications, such as the 3rd Generation Partnership Project (3GPP) Technical Specifications 36.211, 36.212, 36.213, and 36.214, hereinafter respectively referred to as "TS 36.211", "TS 36.212", "TS 36.213", and "TS 36.214", define aspects of LTE communications.
Generally, data from the network to a user device is referred to as downlink data and data from the user device to the network is referred to as uplink data. For example, user equipment (UE), such as a cellular mobile phone, may communicate with an enhanced or evolved Node B (eNode B) via the cellular radio transmission link. Data that is sent from the eNode B to the UE is downlink data, and data that is sent from the UE to the eNode B is uplink data.
Uplink and downlink LTE data is usually transmitted using one or more multiplexing and/or modulation schemes. For example, in some LTE networks, downlink data is transmitted using an orthogonal frequency-division multiplexing (OFDM) and uplink data is transmitted using single carrier frequency-division multiple access (SC-FDMA). Such schemes may allow multiple streams of data to be sent simultaneously (e.g., at different frequencies). While such schemes may allow data to be communicated at high-speed, significant processing is required to encode and decode the data. For example, an eNode B may perform channel coding, multiplexing, and interleaving of data and control streams, which are then sent to the UE over the air (RF) interface. After pre-processing the received signal from the eNode B, the UE may perform channel delineation for downlink physical channels and/or other baseband processing. After separating LTE data from various physical layer channels, the LTE data may be further processed.
In some testing environments, an eNode B may be connected to a testing platform via physical cables. For example, radio frequency (RF) cables may connect antenna ports of the eNode B to antenna ports on the testing platform. If the physical cables are not connected properly between the testing platform and the eNode B, communications between the testing platform and the eNode B may be corrupted or otherwise hindered. Moreover, test operators may have no knowledge of any connection issue and may waste valuable resources, including time, diagnosing connection-related communication issues. While test operators can manually check cable connections for possible misconfigurations, the number of cables and permutations of possible connections can complicate this process. Further, in some setups, the eNode B and the testing platform may be geographically separated, e.g., located in different rooms or locations, creating additional confusion when attempting to manually check physical connections.
Accordingly, in light of these difficulties, a need exists for improved methods, systems, and computer readable media for detecting antenna port misconfigurations.


A tile system, comprising: —a mounting unit, e.g. a rail fixed to a wall; —a tile unit, e.g. a frame holding a decorative tile; —a tile unit-fastening device configured to fasten the tile unit to the mounting unit, e.g. a pin engaging recesses formed on the mounting and the tile unit, the tile unit-fastening device preferably comprising a repositioning mechanism configured to allow the tile unit to move in one or two directions parallel to the wall after the tile unit is fastened to the mounting unit, e.g. the pin having ribs on its outer surface and the recesses being elongated and having cooperating ribs on their elongated inner faces.

Decorative tiles are widely used as wall coverings in both residential and commercial applications, owing at least in part to their versatility, availability in nearly unlimited colors and designs, and durability. Such decorative tiles can be formed from ceramic, marble, granite, quartz, natural stone, porcelain, wood, glass, a variety of metals or polymers, and the like.
When decorative tiles are installed, they are generally laid side-by-side on the intended mounting surface. The tiles are typically affixed directly to the intended mounting surface using one or more of a number of fixatives, including organic adhesives, cementitious thin-sets, mechanical fasteners (e.g., nails, screws, hook-and-loop fasteners, or the like), or the like. The choice of fixative will depend on the composition of the tile and the surface to which it will be mounted. Finally, a cementitious grout material is normally inserted into the joints between adjacent tiles in order to obtain the finished appearance.
The installation process can be quite labor intensive. For example, with wall tiles, installation often requires several days to affix, place, and grout the tiles, including the requisite time to allow the fixative and grout to cure or set.
In recent years, manufacturers have attempted to produce so-called do-it-yourself tile systems that are intended to be easier to install. The goal of such systems is to eliminate the need for skilled labor to correctly and attractively install the tile and finish it with grouting material and/or minimize the amount of time required for the fixative to cure or set. These do-it-yourself designs are mostly aimed toward flooring installations as they generally rely on a combination of the force of gravity, some level of interlocking between adjacent tiles, and/or the dispensing of some type of adhesive during installation to keep the tile in place. In contrast, for wall applications, the tile should be securely fixed to the wall surface to counter the force of gravity. As a result, the do-it-yourself designs are generally not appropriate for installation on walls. In addition, if it is desirable for the installed tiles to be easily removable without causing damage to the tiles or the wall, then normal fixatives for securing the tiles to walls (e.g., adhesives, mastics, cements, and the like) will not be suitable.
Accordingly, there is a need for improved wall tile systems. It is to the provision of such systems, and the associated methods of manufacture and use that the various embodiments of the present invention are directed.

Tile systems and methods of making and using same


A continuous process for making a comb-branched copolymer of an acrylic monomer and a polyether macromonomer is disclosed. The process is performed by continuously feeding a reaction zone with a monomer stream that contains an acrylic acid and a polyether macromonomer, and an initiator stream. The comb-branched copolymer made thereby performs better as water reducing agent in cement compared to that made by a batch process.

Water reducing agents reduce the amount of water needed in cement admixtures, while maintaining good processing ability and consistency. Lignin sulfonates and naphthalene sulfonate-formaldehyde condensates have long been used as water reducing agents. These conventional water reducing agents are readily available and relatively inexpensive. However, they are used in high doses.
In contrast, newly developed polymeric water reducing agents offer high performance but are more expensive to make. U.S. Pat. No. 4,814,014, for example, teaches to graft ethylenically unsaturated monomers onto a polyether. The graft copolymer is used at a low dosage. Unfortunately, it is contaminated with a large portion of nongrafted polyether and ethylenic homopolymer. Because these nongrafted polymers do not function as water reducing agents, they reduce the effectiveness of the product.
Comb-branched copolymers of acrylic acid and polyether macromonomers have been used as high performance water reducing agents (see U.S. Pat. No. 5,834,576). The comb-branched copolymers have more uniform structures compared to the graft polymers of U.S. Pat. No. 4,814,014. Consequently, they have higher water reducing ability. An added advantage of these copolymers is the improved ability to maintain "slump." Slump retention is the workable time after the cement admixture is mixed. Commonly used polyether macromonomers include acrylates, methacrylates, and allyl ethers of polyether.
Methods for preparing comb-branched copolymers of carboxylic monomers and polyether macromonomers are known and relatively simple. In general, free radically polymerizing a polyether macromonomer with a carboxylic monomer forms a comb-branched copolymer. While the related literature briefly mentions batch, semi-batch, and continuous processes (see U.S. Pat. No. 5,834,576, and copending Appl. Ser. No. 09/074,673), no one has suggested that a continuous process would offer comb-branched copolymers that perform better in cement compositions. Specific teachings about how to conduct a continuous process for making comb-branched copolymers are not available. U.S. Pat. No. 5,834,576, for example, only teaches details of a batch process.

Process for preparing comb-branched polymers


A method may include coupling a proximal end of a first cannula to a first manipulator of a surgical system, the first manipulator being configured to remotely actuate movement of the first cannula, wherein the first cannula comprises a rigid portion disposed between the proximal end and a distal end of the first cannula, the rigid portion having a curved longitudinal axis, and coupling a proximal end of a second cannula to a second manipulator of a surgical system, the second manipulator being configured to remotely actuate movement of the second cannula, wherein the second cannula comprises a rigid portion disposed between the proximal end and a distal end of the second cannula, the rigid portion having a curved longitudinal axis. The coupling of the first and second cannulas to the respective first and second manipulators can further include positioning respective first and second centers of motion of the first and second cannulas proximate to each other, and positioning respective longitudinal axes of the first and second cannulas at the first and second centers of motion across one another.

1. Field of Invention
Inventive aspects pertain to minimally invasive surgery, more particularly to minimally invasive robotic surgical systems, and still more particularly to minimally invasive robotic surgical systems that work through a single entry point into the patient's body.
2. Art.
Benefits of minimally invasive surgery are well known, and they include less patient trauma, less blood loss, and faster recovery times when compared to traditional, open incision surgery. In addition, the use of robotic surgical systems (e.g., teleoperated robotic systems that provide telepresence), such as the da Vinci® Surgical System manufactured by Intuitive Surgical, Inc. of Sunnyvale, Calif. is known. Such robotic surgical systems may allow a surgeon to operate with intuitive control and increased precision when compared to manual minimally invasive surgeries.
To further reduce patient trauma and to retain the benefits of robotic surgical systems, surgeons have begun to carry out a surgical procedure to investigate or treat a patient's condition through a single incision through the skin. In some instances, such "single port access" surgeries have been performed with manual instruments or with existing surgical robotic systems. What is desired, therefore, are improved equipment and methods that enable surgeons to more effectively perform single port access surgeries, as compared with the use of existing equipment and methods. It is also desired to be able to easily modify existing robotic surgical systems that are typically used for multiple incision (multi-port) surgeries to perform such single port access surgeries.


Described are a device and system to transmit data to or receive data from one or more data lane interfaces. Each data lane interface may be capable of transmitting a serial data signal to or receiving a serial data signal from a data lane in a device-to-device interconnection. An effective data rate may be varied based, at least in part, upon a number of the data lane interfaces actively transmitting a serial data signal to or receiving a serial data signal from the device-to-device interconnection.

1. Field
The subject matter disclosed herein relates to interfaces between devices. In particular, the subject matter disclosed herein relates to devices capable of transmitting or receiving data at more than one data rate.
2. Information
Semiconductor devices in a printed circuit board (PCB) typically communicate through a device-to-device interconnection (DDI). Such a DDI typically includes copper traces formed in the PCB to transmit signals between devices. A device may be coupled to a DDI by solder bonding or a device socket secured to the PCB.
IEEE Std. 802.3ae-2002, Clause 47 defines a 10 Gigabit Attachment Unit Interface (XAUI) for transmitting data between devices in data lanes. Each data lane typically transmits a serial data signal between the devices using a differential signaling pair. A XAUI is typically coupled to a 10 Gigabit Media Independent Interface (XGMII) which is capable of transmitting or receiving data at a data rate of ten gigabits per second. In addition, the XAUI format may be used in transmitting data over an Infiniband 4× cable as described in the proposed 10GBASE-CX4 standard presently being explored by the IEEE P802.3ak working group.


A method of and an apparatus for monitoring the heart motion of a subject employ a probe which can be coupled to the aortic arch or to the thyroid cartilage of the subject for detecting movements caused by the heart motion and displaying the accelerations and displacement of the heart motion on an acceleration display and a displacement display. A mechanical motion amplifier amplifies the acceleration and an optical amplifier amplifies the displacement to counteract noise.

1. Field of the Invention
The present invention relates to methods of and apparatus for non-invasively monitoring heart motion and is useful for the non-invasive monitoring of cardiac functions, in particular, but not exclusively, of human hearts.
2. Description of the Related Art
In the past, methods for the non-invasive monitoring of cardiac function have included:                Mechanical methods, for example, pulse recording of the jugular carotid artery or apex cardiography.        Electrical techniques, for example, electrocardiograms (ECGs).        Imaging techniques, including echocardiology, radiography and magnetic resonance imaging (MRI).
However, mechanical methods are inaccurate because of physical differences between subjects. For example, the intensity of heart sounds cannot be accurately measured because of the fat thickness layer differences.
Some non-invasive mechanical methods do not couple properly to the external movement generated by the heart and are therefore of little use.
The electrical techniques cannot correlate to the force of cardiac contraction and are therefore of little use, and imaging techniques are also subject to this problem. For example, an echocardiogram determines a ratio known as the "ejection fraction", which is a measure of cardiac performance which may or may not be related to the force of the heart's contraction. In a normally functioning heart, this relationship may hold true, but this finding is unreliable because the head pressure of the cardiovascular system is unknown.
None of the above-mentioned prior methods or techniques can accurately measure the isovolumic phase of the heart cycle, which is the most important parameter to measure in identifying coronary artery disease.
In U.S. Pat. No. 5,865,759, issued Feb. 2, 1999 to the present inventor, the disclosure of which is incorporated herein by reference, there is disclosed an apparatus and method to assess cardiac function in human being which employ a sensing mechanism positioned on the thyroid cartilage in the neck against the trachea for sensing a response of the thyroid cartilage to heart function.
While this prior patent disclosed a restraining system to hold the sensing mechanism in position, it was found that the apparatus is extremely sensitive to gravity because the force resulting from the weight of the sensing mechanism and a sensor restraining system varied in dependence on the vertical and horizontal position of the subject under test.
Consequently, a large cardiac force would decouple the sensing mechanism, so that a subsequent low magnitude force would be recorded poorly or not at all. These weak forces were so poorly recorded that very large electronic amplification was used, resulting in a poor signal-to-noise ratio and the recording of mostly noise. The poor coupling resulted in false data, which showed a poor correlation between the isovolumic contraction phase and the ejection phase of the heart cycle in nominal hearts, as shown by a clinical study. Another result was that the diastolic part of the cycle could not be recorded. This is a very important phase in which the passive inflow into the ventricles occurs and data relating to this phase could indicate the elasticity of the ventricular muscle. Furthermore, this prior apparatus was difficult to operate because positioning the sensor on the thyroid cartilage was difficult as elastic members forming parts of the restraining system had to be in tension balance to prevent the sensing mechanism from being moved to one side or another of the thyroid cartilage, causing erroneous data. Also, with this prior apparatus, mechanical interference caused by the sensor restraining system and an accelerometer forming part of the sensing mechanism contacted clothing, pillows, beards, fatty neck tissue, and in the case of a short neck contacted the chest, resulting in huge errors. Because no coupling apparatus was provided in this prior system, the addition of more sensors was not possible nor could reliable data be obtained. Also, this prior system employed wire connections extending directly to a recorder, resulting in stiffness and inertial effects due to interference of the wiring with the motion of the sensor.

Methods of and apparatus for monitoring heart motions


An extended resistance temperature sensor formed of a plurality of lengths of pre-insulated resistance temperature detector (RTD) wire. The RTD wire is either unheated, self heated or is heated by means of strands of heater wire integrated with or placed closely adjacent to the RTD wire. The RTD wire itself, or together with the heater wire, is bonded together in one embodiment. Alternatively the RTD wire, or with the heater wire, may be encased in insulated shrink tubing, thin wall metal tubing or both. Connectors are provided to supply electrical current for heating purposes or to connect the RTD wire to detection circuitry, or both. Protective sheaths are provided over the connectors.

Both thermocouples and RTD's are in widespread use for sensing temperature and providing an electrical output representative of the temperature sensed. Thermocouples, by their nature, are point sensors because they thermoelectrically produce an electromotive force at a specific junction between two different materials. RTD's employ a wire sensing element which has a resistance which varies with temperature. Most RTD's are now designed to concentrate the electrical resistance to a small point or in the smallest possible volume, with miniaturization being a principle feature so that RTD's are, like thermocouples, essentially point sensors. Because of this point sensing feature, whenever an extended field is to be interrogated with the use of either thermocouples or RTD's, it has generally been necessary to distribute a multiplicity of differentially heated differential thermocouples or differential RTD's and measuring the heat loss at the particular point where the differential temperature is being sensed.
No matter how many point sensing thermocouples or RTD's are distributed in the field, they are unable to provide an accurate, true analog representation of the information to be determined from the field because they are still only sensing specific points. Determining the best points to interrogate, installing the individual sensor elements, and making the numerous required individual electrical connections to the point sensing elements in accordance with the generally accepted technology, are cumbersome and expensive steps.
There are many situations where it is desirable to sense level or flow rate over an extended field. This has been accomplished to a certain degree with thermocouples and RTD's by converting the point sensing reading to an average temperature of the field. However, the larger such a differential thermal field is, and the more varied the temperatures are across the field, the more point sensing elements are required to obtain a readout which is reasonably representative of the average condition of the field.
One situation where extended field interrogation is currently made with thermocouples or RTD's involves gauging of the fluid level, or the location of a phase change interface such as between liquid and gas, in a vessel such as a tank. This type of level gauging can currently be accomplished with thermocouples and RTD's by arranging a series of spaced sensor elements along the height of the tank, that is, at vertically separated points in the field being interrogated. In the case of RTD's, a series of heated RTD's and companion reference RTD's are employed along the height of the tank. As liquid reaches each RTD point sensor, the sensor reports that it is wet when it is cooled by the higher thermal dispersion rate of the liquid than is the case for the air or gas phase above the surface of the liquid. However, the operator is unable, with such point sensing structure, to determine whether the liquid level is just at that particular point or at any level between that point and just below the next higher RTD sensing point. Further filling of the tank will result in discrete reports from the sequentially higher RTD's, while lowering of the liquid level will cause successive discrete reports from the successively lower RTD's as they are uncovered from the liquid. For example, if ten sensing points are employed along the height of the tank, each with an individual heated RTD sensor and a reference RTD sensor, the gauging can only be performed at ten individual step points with unresolvable uncertainty of where the liquid level is between any two of those points. The only way to reduce such uncertainty when employing point sensors is to increase the number of sensing elements, at correspondingly increased expense, cumbersome wire connections and possibly reduced reliability.
Accurate liquid level sensing is of critical importance in any liquid storage vessels and particularly in reactor buildings of nuclear power plants, as well as in the reactor vessels themselves. This accurate liquid level sensing is important in avoiding nuclear power plant accidents which could be caused when the actual level of the liquid is either not properly known or is misinterpreted. In addition to lack of desired accuracy, liquid level changes are not immediately sensed when point sensors are used since there can be considerable change in liquid level prior to detection by the next sensing element which is either covered or uncovered. Thus, a developing problem or trend may not be immediately detected and the desirable mitigating action to suppress or correct the problem cannot be taken in as timely a manner as may be desirable or necessary.
Each of the vertical sequence of thermocouples or RTD's in such a liquid level gauging system requires its own separate electrical connections to the detection circuitry. The thereby required large number of joints or splices can result in undesirably low reliability, which could be especially dangerous in the environment of a nuclear power plant. As an example of this problem, there is in existence a point-sensing RTD system for water level sensing in a nuclear reactor building which has approximately fifty RTD sensors arrayed over a vertical height of about sixty feet.
RTD's are preferred for some purposes over thermocouples because they can be made more sensitive, being able to provide an output signal many times greater than is generally possible with thermocouples. This is primarily because RTD's operate with an external electrical power source which can provide as high a level of voltage or current as is desired. Thermocouples operate on the basis of a self-generated junction electromotive force (emf) which inherently has a very low output voltage level as well as other inaccuracies.
For sensing in some extended fields, such as the inside of a nuclear reactor vessel, access may be relatively difficult and may be best achieved by encasing a series of sensors in a long, slender, tubular probe. Such a probe can be readily inserted in an existing reactor vessel instrument guide tube. RTD's are desirable in such situations because of their high output and therefore high sensitivity but many prior art RTD's are not suitable for such packaging, being too bulky and having a ceramic or a glass insulator too brittle to allow them to be deformed as would be required for packaging in a long, slender, tubular probe.
On the other hand, thermocouples have been packaged inside a metal casing as small as 0.01 inch in diameter. A series of such encased thermocouples and the required electrical leads may be placed inside a tube and encased by drawing or swaging the tube down around the thermocouples and leads to produce a long slender probe suitable for gaining access in restricted regions inside a nuclear reactor vessel. This advantage for the thermocouples is balanced by at least one equivalent disadvantage. Thermocouples are relatively delicate and are easily subject to breakage during the manufacture of such probes or upon accidental impacting. Of course, as discussed above, a thermocouple being a point sensor, thermocouple probes necessarily have a step function output rather than a continuous output, so the accuracy of liquid level determination is limited. Additionally, the electrical output of thermocouples is so small that performance is grainy and resolution and accuracy are relatively poor. Because individual wire leads are required for each thermocouple, numerous wires must extend along the probe, thereby limiting how small the outside diameter of a tubular probe can be. Of course, the greater the number of thermocouples placed along the probe in any attempt to increase resolution the greater the number of leads. This large number of leads also seriously reduces the reliability of thermocouple-type probes. Thermocouple probes are relatively expensive to make, especially considering the number of leads, connections and electronic cooperating devices required for such probes.
Another example of an extended field which has been interrogated by a multiplicity of RTD's or thermocouple sensors, is a large duct having a non-uniform flow profile, where it is sought to obtain an average reading of the flow velocity in the duct. Such non-uniform flow distributions exist, for example, in air ducts where diameters are large and fittings such as tees, elbows, transitions, bends, section changes, louvers, dampers and the like cause flow disturbances. Non-uniform flow distributions also typically occur in the input air ducts and combustion output ducts of fossil fuel power plants. In such cases, a multiplicity of point sensing elements is placed at what are considered to be strategic locations across the gas flow path, but only a rough approximation of the flowable velocity can be obtained by the use of such discrete, point sensing locations. As stated previously, a large number of individual point sensors results in high costs due to the number of leads, connectors and mating electronic devices that are necessary to cooperate in interpreting the individual signals.

Heated extended resistance temperature sensor, apparatus for sensing and method of making same


A computer system includes at least one real machine provided with a machine controller and/or a plurality of virtual machines provided with a machine controller and an operating system for a virtual machine, the real machine and the plurality of virtual machines are connected to a shared memory.

1. Field of the Invention
The present invention relates to a computer system comprising a plurality of machines connected to a shared memory and a control method for a computer system comprising a plurality of machines connected to a shared memory. More particularly, the present invention relates to a computer system comprising a plurality of machines connected to a shared memory and a control method for the same system, wherein improved controls are attained than in conventional systems.
Recently, computer systems in which a plurality of machines are connected to each other via a shared memory are generally used because of a reduced rate of evolution in the capability of a single processor and a strong need for improvement in reliability. There is also a demand for operating a computer system as a plurality of virtual computer systems, by using a shared memory.
Further, there is a demand for a system having a hot-standby capability, wherein it is possible to detect a system down occurring when a system operated under an AVM (an OS for controlling a virtual computer system) is down due to an abnormality.
2. Description of the Prior Art
(1) Conventional computer systemxe2x80x941
A description will first be given of a first conventional computer system.
FIG. 1 shows the construction of a first conventional computer system.
In the example of FIG. 1, a machine 10 is operated as a plurality of virtual machines 11-1-11-n (hereinafter, referred to as logic machines). The machine 10 has an operating system (hereinafter, referred to as an AVM) 12 for controlling the logic machines 11-1-11-n.
(2) Conventional computer systemxe2x80x942
Secondly, a description will be given of a case where a computer system is connected to a shared memory.
FIG. 2 shows the construction of a second conventional computer system.
In the example of FIG. 2, the above-mentioned machine 10 is connected to a shared memory 50. The machine 10 and the shared memory 50 is connected via a real access path 60 provided in the shared memory 50. The machine 10 reads information from and writes information to the shared memory 50.
The machine 10 is provided with the AVM 12 and the plurality of logic machines 11-1-11-n. A logic (virtual) access path 71 is disposed between the AVM 12 and each of the logic machines 11-1-11-n. The logic machines 11-1-11-n read information from and writes information to the shared memory 50 via the access path 71 and the AVM 12.
FIG. 3 is a diagram explaining the second conventional computer system.
In the second conventional computer system shown in FIG. 3, the machine 10 is connected to a shared memory 51 via an access path 61, and a machine 20 is connected to the shared memory 51 via an access path 62. A machine 30 is connected to a shared memory 52 via an access path 63, and a machine 40 is connected to the shared memory 52 via an access path 64.
The machine 10 connected to the shared memory 51 is executing a process with respect to the shared memory 51. One of the logic machines in the machine 20 is in a standby state under the control of the AVM, and another in the machine 20 is used in developing a computer system. The machine 30 connected to the shared memory 52 is executing a process with respect to the shared memory 52, and the machine 40 is in a standby state. In this way, exclusive control is imposed when the system shown in FIG. 3 is in a hot-standby mode such that, while one of the machines 10 (30) is executing a process with respect to the shared memory 51 (52), the other machine 20 (40) is in a standby state.
(3) Conventional computer systemxe2x80x943
Thirdly, a description will be given of a case where a plurality of machines are connected to a shared memory.
FIG. 4 shows the construction of a third conventional computer system.
In the computer system shown in FIG. 4, a plurality of machines 10, 20, 30 and 40 are connected to the shared memory 50. The machines 30 and 40 are operated as virtual machines. Logic machines in each of the virtual machines 30 and 40 are provided with a relative machine No. For example, the logic machine 31-1 is provided with an No. 1, the logic machine 31-2 an No. 2, the logic machine 31-3 an No. 3, and the logic machine 40 an No. 4. Likewise, the logic machine 41-1 of the virtual machine 40 is provided with an No. 1, the logic machine 41-2 an No. 2, the logic machine 42-3 an No. 3, and the logic machine 41-4 an No. 4. Further, the machine 10 is provided with a real machine No. 0, the machine 20 a real machine No. 1, the machine 30 a real machine No. 2 and the machine 40 a real machine No. 3.
A description will be given of a case where an operator 80 specifies the logic machine 31-1 of the machine 30. When the operator 80 specifies the real machine No. 2 of the machine 30, it means that an AVM 32 of the machine 30 having the real machine No. 2 is specified. According to a predetermined sequence, the AVM 32 specifies a relative machine No. 1, for example, indicating the logic machine 31-1 of the machine 30. In a computer system comprising a plurality of machines connected to each other via a shared memory, a virtual machine operated under the AVM allows only one logic machine under its control to be connected to another computer. Since, the real machine No. and the logic machine are in one-to-one correspondence at a given moment, it is possible to specify a logic machine by specifying a real machine No. When the operator 80 specifies the real machine No. 2, for example, it means that the logic machine 31-1 is specified.
(4) Communication method in a conventional computer system
Fourthly, a description will now be given of a communication undertaken between the machines in a conventional computer system.
FIG. 5 is a diagram explaining communication system of a third conventional computer system. As shown in FIG. 5, the plurality of machines 10, 20 and 40 and the like share the shared memory 50. Communication between the machines via the shared memory 50 is executed such that an originating machine specifies a real machine No. of a destination machine. For example, assuming that the machine 10 has a real machine No. 0 and the machine 20 has a real machine No. 1, the machine 10 requests communication with the machine 20 by specifying the real machine No. 1. The machine 40 is provided with a plurality of logic machines 41-1-41-n. It is possible for the logic machine 41-3 of the machine 40 to communicate with the machine 20 via an AVM 42 and the shared memory 50, by specifying the real machine No. 1 of the machine 20. In this way, communication among the machines 10, 20 . . . via the shared memory 50 is possible by specifying the real machine No.
(5) Interruption handling in conventional communication
A description will now be given of interruption handling effected in conventional communication.
In the above-described system in which a plurality of machines share a shared memory, communication between virtual machines is possible using a GSIGP instruction. In order to keep track of how an interruption is pending or reflected (processed), communication process as shown in FIG. 6, which process is based on the pending status of an interruption, is conducted. GSIGP instructions have the function of allowing communication between machines and controlling remote machines. The function of controlling remote machines is taken advantage of when a downed machine is to be controlled. In this case, a GSIGP instruction is used to halt the operation of a CPU, reset the I/O and to begin a memory dump.
FIG. 6 is a sequence chart explaining interruption handling in conventional communication.
It is assumed that the machine A communicates with the machine B.
step 1) The machine A issues a GSIGP instruction for requesting communication to the machine B via a shared memory.
step 2) The machine B puts the interruption in a pending state by hardware means because the interruption is not reflected.
step 3) Upon an occurrence of a next communication request, the machine A issues a GSIGP instruction via the shared memory.
step 4) Upon a determination that the interruption is pending in the machine B, the shared memory receives the GSIGP instruction from the machine A, assuming that the interruption will be reflected by the machine B later, and queues the communication request from the machine A.
step 5) When the machine B is ready to reflect the interruption, the hardware of the machine B cancels the pending state of the interruption and causes the interruption to be reflected.
step 6) The machine B processes the pending communication request and the communication request queued in the shared memory.
Communication requests may be queued in the shared memory so that a plurality of communication requests may be processed in the event of an interruption.
(6) Conventional system control
In a conventional complex system in which machines are connected to each other via a shared memory, system control involving resetting of a downed machine by another machine, using a GSIGP instruction (reset), is enabled. When such a resetting is completed, the system switching according to hot-standby scheme is conducted.
FIG. 7 is a sequence chart explaining resetting process in conventional system control.
In the description that follows, it is assumed that the machine A controls resetting of the machine B.
step 10) The machine A issues a GSIGP instruction (reset) in order to reset the machine B.
step 11) The machine B begins its resetting by hardware means upon receipt of the GSIGP instruction via the shared memory.
step 12) The machine A issues a GSIGP instruction (sense) to determine whether the resetting is completed or the machine B is in the process of its resetting.
step 13) The machine A recognizes that the machine B is in the process of its resetting based on the result yielded in response to the GSIGP (sense) instruction.
step 14) The machine B completes its resetting by hardware.
step 15) The machine A issues a GSIGP instruction (sense).
step 16) The machine A recognizes that the machine B has completed its resetting based on the result yielded in response to the GSIGP instruction (sense).
(7) Conventional process executed conventionally in the event of a system down
Conventionally, when an OS detects a system down, the OS controls the downed machine by a GSIGP (halt CPU) or a GSIGP instruction (reset). A GSIGP instruction is honored and executed by a service processor (SVP) provided in each machine. The service processor assumes that GSIGP instructions (pending) may continue to be issued endlessly and effects forced resetting when a predetermined period of time has expired.
In case a logic machine is deactivated, an AVM recognizes the deactivation of the logic machine and removes the logic machine from the service by disconnecting a logic path between the logic machine and the AVM.
However, the aforementioned aspects (1)-(7) of the conventional system have the following problems.
(1) In the systems shown in FIGS. 1 through 3, a machine is provided to stand alone or connected to a shared memory directly. While it is possible for a machine in the latter configuration to exchange information with other machines, there is a problem in that the access of only one machine under the control of an AVM to the shared memory is enabled.
(2) When initialization by a plurality of machines is executed using an IPL, there is a likelihood that initialization is executed by the plurality of machines simultaneously, with the result that data compatibility may suffer. When there is a hang-up in the OS that mediated the IPL operation so that the OS is restarted, an erroneous operation of the system may result.
(3) In the system shown in FIG. 4, the AVM is capable of specifying a logic machine in correspondence to the specification by the operator and in accordance with a predetermined order. However, in the system shown in FIG. 8, wherein no predetermined specification order is determined for a plurality of logic machines in a virtual machine, specification of a logic machine only by means of a real machine No. is impossible. The same thing is true of a system in which logic machines in a virtual machine are operated concurrently. Referring to FIG. 8, when the operator 80 specifies a real machine No. 2 of the machine 30, the control is turned over to the AVM 32 of the machine associated with the real machine No. 2. However, the AVM 32 cannot determine which logic machine included in the machine 30 is to be specified. Therefore, it is impossible to process communication involving a specific logic machine.
(4) In a conventional scheme, only one logic machine out of a plurality of logic machines in a virtual machine connected to the shared memory can use the shared memory. That is, in a complex system where a plurality of machines operated as virtual machines each comprising a plurality of logic machines are connected to each other via a shared memory, it is impossible to specify a logic machine controlled in each virtual machine by real machine Nos.
(5) When a communication request is issued from a real machine to a virtual machine in a conventional configuration where real machines and virtual machines share a shared memory, an associated interruption is reflected by the originating machine before the communication request is reflected by the destination virtual machine. Therefore, the interruption does not become pending in the hardware of the destination machine. Accordingly, the other machines in this system recognize that this interruption is reflected. When the destination virtual machine is not ready to reflect an interruption, it is impossible for a real machine to keep track of the state of the virtual machine with regard to interruptions. Specifically, even if the virtual machine is in a pending state, requests to the virtual machine arrive one after another at the central program of the originating machine, causing the central program to discard the interruption. As a result, communication having as its destination a virtual machine cannot be executed properly.
When a communication request is queued in the shared memory due to the pending state of a first virtual machine and then an interruption requesting a second virtual machine occurs subsequently, the first interruption is not reflected readily because the destinations are different.
(6) When a GSIGP instruction (for CPU) is issued in a conventional configuration system where a plurality of virtual machines share a shared memory, as is done between machines operated as real machines, the CPU of the machine operated as a virtual machine comes to a halt. Even if the xe2x80x9cinterruption control method for communication between computer systemsxe2x80x9d disclosed in Japanese Laid-Open Patent Application No. 5-324362 is applied to a system in which a plurality of virtual machines share a shared memory, the machine that originated a GSIGP instruction (reset) may be unable to recognize a reset completion properly. Specifically, while a logic machine (for example, a logic machine a) in a virtual machine is being reset in response to a GSIGP instruction (reset) issued by a machine (for example a machine A), a request for resetting or communicating with a logic machine b operated under a same control program as the logic machine a, which request is issued by another machine (for example, a machine B), cannot be processed. In order to resolve this situation, the control program may instruct the hardware to cancel the xe2x80x9creset proceedingxe2x80x9d state when the control program initiates resetting of the AVM. However, this has a problem in that the machine that originated the GSIGP instruction (reset) is unable to recognize completion (cancellation of the xe2x80x9creset proceedingxe2x80x9d state) of the reset properly. FIG. 9 is another diagram explaining a problem with the prior art. Encircled numbers in FIG. 9 correspond to the numbers in the parentheses at the beginning of each description below.
(1) A machine A issues a GSIGP instruction (reset of logic machine a) for resetting a logic machine a in a machine V operated as a virtual machine.
(2) The reset request from the machine A is put in a pending state in the machine V by the hardware thereof.
(3) When the AVM of the machine V recognizes the reset request, the AVM executes a resetting process of the logic machine a.
(4) A machine B issues a GSIGP instruction (reset of logic machine b) for resetting a logic machine b in the machine V.
(5) Since the hardware of the machine V is executing the resetting process, the reset request from the machine B is not honored.
(6) When the resetting of the logic machine a is completed, the AVM instructs the hardware to cancel the pending state of the reset request.
(7) The machine A recognizes completion of the resetting of the logic machine a of the machine V.
In other words, while a resetting process is being executed in a virtual machine in response to a reset request issued by a first machine, it is impossible for a second machine to request resetting of or communication with the virtual machine operated under the AVM executing the resetting process.
FIG. 10 is yet another diagram explaining a problem with the prior art. Encircled numbers in FIG. 10 correspond to the numbers in the parentheses at the beginning of each description below.
(1) A machine A issues a GSIGP instruction (reset) for resetting a logic machine a in a machine V operated as a virtual machine.
(2) The hardware of the machine V holds the reset request according to the method disclosed in Japanese Laid-Open Patent Application No. 5-324362 (xe2x80x9cinterruption control method for communication between computer systemsxe2x80x9d).
(3) The AVM of the machine V recognizes the reset request and instructs the hardware to cancel pending state of the reset.
(4) The AVM executes the resetting process of the logic machine a.
(5) The machine A recognizes completion of the resetting process of the logic machine a of the machine V.
Thus, there is a problem in that the machine that originated the GSIGP instruction (reset) erroneously recognizes completion (cancellation of the xe2x80x9creset proceedingxe2x80x9d state) of the resetting process if the AVM of the machine V instructs the hardware to cancel the resetting process.
Further, if a logic machine in a machine operated under the AVM is down in a system configuration in which a plurality of machines are connected via a shared memory, a service processor provided in each machine is unable to perform a forced reset normally carried out when a resetting process is not completed within a predetermined period of time. This is because the service processor activates a forced reset when it recognizes a pending state. Cancellation of the xe2x80x9creset proceedingxe2x80x9d state by the AVM causes the monitoring of the service processor using a timer to stop. Since the service processor is unable to recognize a pending state, it is unable to perform a forced reset.
Further, when a logic machine operated under the AVM is deactivated, a logic path between the AVM and the logic machine is disconnected so that the OS cannot control the logic machines. For example, the OS cannot reset a logic machine. For this reason, there is a problem in that an operator has to reset a logic machine whenever the logic machine is deactivated.
Accordingly, an object of the present invention is to build a large-scale computer system in which loads must be distributed across a plurality of machines, by connecting a plurality of computer systems to a shared memory that allows communication between a plurality of machines operated as a virtual machine and having a plurality of logic machines.
Another and more specific object of the present invention is to provide a computer system comprising a plurality of machines connected to a shared memory, wherein, when an initialization of the shared memory is started, an updating request from another machine is subjected to exclusive control, and, when one of the machines is put out of service, system failure due to, for example, a restart is prevented.
Still another object of the present invention is to provide a computer system comprising a plurality of machines connected to a shared memory, wherein the AVM of a machine operated as a virtual machine assigns machine Nos. to logic machines under its control so that both the AVM and the control system of the logic machine are capable of recognizing the computer Nos.
Still another object of the present invention is to allow flexible communication in a system in which a plurality of machines are connected via a shared memory.
Yet another object of the present invention is to provide a computer system comprising a plurality of machines connected to a shared memory, wherein an interruption to the AVM is properly reflected.
Another object of the present invention is to provide a computer system comprising a plurality of machines connected to a shared memory, wherein completion of a resetting process in response to a GSIGP instruction (reset) is properly recognized by a machine that originated the instruction.
Still another object of the present invention is to provide a computer system comprising a plurality of machines connected to a shared memory, wherein it is possible to detect an abnormality of the AVM and notify other machines of the abnormality, and it is possible for a machine to control a real machine that went down or the logic machines in the machine operated under the AVM in which the abnormality is found.
Yet another object of the present invention is to provide a plurality of machines connected to a shared memory, wherein it is possible for a machine that went down to notify other machines connected to the shared memory of a state of the system down.
Another object of the present invention is to provide a computer system comprising a plurality of machines connected to a shared memory, wherein, when there is a machine in which a system down occurs, it is possible for the OS of another machine to recognize the system down.
Still another object of the present invention is to provide a computer system comprising a plurality of machines connected to a shared memory, wherein, a machine that recognizes a downed machine is capable of controlling the downed machine.
Yet another object of the present invention is to provide a computer system comprising a plurality of machines connected to a shared memory, wherein it is possible to halt the operation of the CPU of a downed machine and reset the I/O thereof so that a hot-standby state is introduced.
Another object of the present invention is to provide a computer system comprising a plurality of machines connected to a shared memory, wherein control of a downed machine is effected such that, when a virtual machine goes down, it is possible to force a reset thereof using the hardware, similarly to the case of a real machine.
Still another object of the present invention is provide a computer system comprising a plurality of machines connected to a shared memory, wherein an operator interruption message once displayed is extinguished immediately when the operator completed its interruption.
In order to achieve the aforementioned objects, the present invention provides a computer system comprising a plurality of machines connected to a shared memory, the computer system including at least one real machine and/or a plurality of virtual machines, wherein each of the virtual machine is provided with an AVM for controlling a virtual machine, and the real machine is provided with an OS for controlling the real machine and individual logic machines in the virtual machine.
In accordance with one aspect of the present invention, it is possible to connect a plurality of machines operated as virtual machines to a shared memory, wherein communication between a virtual machine operated in a machine and a virtual machine operated in a separate machine is possible.
In accordance with another aspect of the present invention, it is possible for a virtual machine connected to a shared memory to lock a shared memory in a hot-standby mode so that an access from another machine is subject to exclusive control. When an abnormal halt of the operation of the locking machine is detected, it is possible for a detecting machine to initialize the failed machine so that an access path between the failed machine and the shared memory is disconnected. Thereby, disruption of data is prevented.
In accordance with still another aspect of the present invention, when an initialization process of a logic machine in a virtual machine is halted due to an abnormality, a logic path between the failed logic machine and the OS (AVM) that controls the failed logic machine is disconnected. Since an access path for the virtual machine is not disconnected, it is possible for the other logic machines under the same AVM to access the shared memory.
In accordance with yet another aspect of the present invention, identifiers are assigned to each of a plurality of logic machines operated in a virtual machine connected to a shared memory. Thus, upon being started, the OS of the logic machine inquires, as required, the identifier of itself of the AVM that controls the logic machines. Therefore, it is possible to identify a call originating logic machine and/or a call receiving logic machine in communication involving a logic machine.
In accordance with another aspect of the present invention, a determination is given in communication as to whether the destination machine is a real machine or a machine operated as a virtual machine. Information necessary for communication between a plurality of machines is exchanged so as to keep track of the operating state of the machines. Therefore, it is possible to effect communication wherein the state and identity of the communication destination is properly recognized, even in a complex system where real machines and virtual machines are connected to via a shared memory.
In accordance with another aspect of the present invention, when a virtual machine receives a request for communication from another machine, a determination is made by the virtual machine as to whether or not the request has as its destination the virtual machine or another machine. When the request has as its destination the virtual machine, the virtual machine queues the communication request under the control of the OS until the logic machine requested is ready for a communication process. When the logic machines is ready for the process, the communication request is reflected.
In accordance with still another aspect of the present invention, communication requests for a plurality of logic machines are queued. When a logic machines is ready for the communication, the logic machine is notified of the request. The OS of the notified logic machine determines whether or not the there are other communication requests queued. When there are, those communication requests are also processed. In this way, communication requests are properly reflected even when there is a new interruption, or different communication interruption states exist between the requested logic machine and the machine which controls the same logic machine.
In accordance with yet another aspect of the present invention, when there is an overflow of a queue, the OS controlling the requested logic machine notifies the machine that originated the communication request of the overflow of the queue so that a new communication request is prevented from being issued.
In accordance with another aspect of the present invention, when a virtual machine receives a reset request from another machine, the OS controlling the logic machines determines the logic machine that is the target of control. When the control of the logic machine is completed, the OS notifies the machine that originated the reset request of the completion of the control. Therefore, the machine that issued the reset request is able to switch to a hot-standby mode.
In accordance with still another aspect of the present invention, it is possible for the OS controlling a logic machine to receive a communication request from another machine while the OS is executing the resetting process.
In accordance with yet another aspect of the present invention, when the AVM is down due to an unrecoverable error, the failed virtual machine itself is able to notify the other machines connected to a shared memory of the system down via the shared memory. Thereupon, it is possible for one of the other machines connected to the shared memory to control the downed machine; i.e., reset the input and output of the downed machine or halt the operation of the CPU of the downed machine. Instead of allowing a communication session between the downed machine and the machine that received the system down being continued even after the occurrence of the system down, thereby inviting a chance of an error occurring, this aspect of the invention ensures that the downed machine is disconnected from the system logically.
In accordance with another aspect of the present invention, the state of the downed machine can be properly recognized. Specifically, the state of the downed machine in which a failure occurred during a communication session can be properly recognized. Therefore, it is possible to control the downed machine; i.e. reset the input/output of the downed machine or halt the operation of the CPU of the downed machine. Thus, it is ensured that the downed machine is disconnected from the system.
In accordance with still another aspect of the present invention, the OS waits for a notification of completion of a control from the AVM according to a timer monitoring scheme. When there is no completion notification or failure notification from the AVM within a predetermined period of time, it is determined that a logic machine in the machine operated under the AVM is down.
In accordance with yet another aspect of the present invention, when a logic machine in a virtual machine is down, the logic machines other than the downed logic machine are also regarded as being down. Thus, all the logic machines in the virtual machine are disconnected from the system. In this way, a high-speed stand-by process becomes possible by effecting control with respect to the hardware of virtual machine.
In accordance with another aspect of the present invention, halt of the CPU operation and the reset of the input/output are allowed in a virtual machine. While the I/O reset control according to the prior art is possible only in a real machine not operated under the AVM, the present invention allows such a control in the virtual machine as well.
In accordance with still another aspect of the present invention, when the OS detects a down of the AVM and when there are any other machine (which may be a virtual machine) other than the logic machines operated under the AVM, the other machine takes control of the downed machine. Alternatively, if there are no machines other than the logic machines operated under the downed AVM, one of the logic machines under the control of the AVM takes control of the downed machine.
In accordance with yet another aspect of the present invention, when a logic machine in a virtual machine is deactivated, the virtual machine notifies another machine of the deactivation. However, the AVM for the deactivated logic machine is responsible for controlling the downed machine or resetting the deactivated logic machine. Therefore, control by means of GSIGP instructions is not necessary. In this way, it is possible to control the deactivated machine; i.e., reset the I/O thereof or halt the operation of the CPU thereof.
In accordance with another aspect of the present invention, it is possible for a machine to receive a notification of a deactivation of another machine.
In accordance with still another aspect of the present invention, an operator interruption message displayed when the control of the downed machine fails is extinguished so as to reduce the degree of operator interruption. Accordingly, a hot-standby mode is attained without an interruption by an operator.

Computer system comprising a plurality of machines connected to a shared memory, and control method for a computer system comprising a plurality of machines connected to a shared memory


The present invention provides a sprayable gel-type skin/mucosa-adhesive preparation comprising a gel formulation which contains an active pharmaceutical ingredient in a gel base material comprising a skin/mucosa-adhesive agent and an administration system comprising the preparation.

Currently, as a method for administrating a medicament, it is often used to spray a liquid drug preparation put in a spray container, to a mucosa and skin of a lumen and body surface. Especially, a drug preparation for intranasal administration is often used. The medicaments used for this purpose had been limited to a regional use such as a treatment for rhinitis. However, these days such administration is getting some attention for the purpose of systemic action. Low-molecular medicaments for systemic action such as butorphanol and sumatriptan, and peptidic medicaments such as calcitonin and desmopressin have been already sold in the market as a drug preparation for intranasal administration, and furthermore a lot of new applications via intranasal administration have been tried to get some absorption-improvement or fast-act.
The merits of a drug preparation for spray-administration to mucosa, especially a drug preparation for intranasal administration include that (1) fast act of a drug is expected because of its rapid absorption, (2) it is possible to avoid the decomposition of a drug due to the first-pass in liver, (3) it is possible to avoid the decomposition of a drug due to gastric acid or gastrointestinal enzyme in gastrointestinal tract, (4) it is possible to reduce the dose of a drug because of its high bioavailability, (5) it is a noninvasive administration compared with injection, (6) a patient can treat himself/herself, (7) a drug can directly reach the blood circulation or central nervous system, etc., while the demerits of a drug preparation for intranasal administration include that (1) the dose of a drug which can be administered to nasal cavity is limited to 25-200 μL per one operation, (2) a compound having a high molecular weight of 1 kD or more is hard to be absorbed via this route, (3) the absorption of a drug might be affected by the pathological state of nasal cavity, (4) the state of nasal cavity is varied between individuals, (5) the elimination system by mucociliary clearance might affect the absorption of a drug, (6) intranasal enzyme barrier exists, (7) nasal mucosa might be irritated by a drug, etc.
Nasal cavity is a site which first gets in contact with the outside, as well as oral cavity, which have a very outstanding character about the foreign-material-removal and prophylaxis. The abnormal activation of these actions or the failure thereby can cause rhinitis, nasal allergy, etc. Especially, pollinosis (hay fever) is becoming a serious social problem. For the purpose of the treatment of these nose-localized diseases, a lot of nasal spray preparations containing a vasoconstrictor agent, an antiallergic drug, a steroid, etc. have been put on the market.
Recently, some nasal absorption-type preparations containing a bioactive peptide or a water-soluble peptide having a molecular weight of 1000-3000 have been put on the market. These water-soluble high-molecular medicaments are ineffectual via oral administration, but effective only via injection. However, nasal administration can arrive at high bioavailability of several % to several 10%. The main reason thereof is thought that the permeability of epithelial layer in nasal mucosa which is an absorption path for water-soluble high-molecular medicaments is even higher than that of gastrointestinal tract or other mucosa. Thus, a nasal absorption-type preparation containing a water-soluble high-molecular medicament which is expected as a systemically effective formulation, is thought to be very useful as a noninvasive formulation type instead of an injection formulation.
Recently, a nasal absorption-type preparation which can be expected to mitigate an acute pain has been researched/developed as a narcotic analgesic and a migraine drug, on the basis of the fact that the permeability of epithelial layer in nasal mucosa is superior to that of other mucosa. A nasal absorption-type preparation containing such a medicament having central nervous system effect can markedly contribute the improvement of a patient's QOL, because it is expected to exert the pharmacological action more rapidly than a preparation for oral administration and it is possible to be administered by patient itself. A nasal cavity has a NALT (nasal-associated lymphoid tissue) which is similar to a lymphoid tissue. These days, some drug preparations for intranasal administration comprising influenza vaccine, diphtheria vaccine, etc. have been researched/developed as a vaccine-administration route for airborne-infectible virus, because the nasal immunoresponsiveness is high. Thus, it is so expected that a drug preparation for intranasal administration would be developed on the basis of the anatomical/physiological property of nasal cavity. However, for the drug design thereof it is required to understand the anatomical/physiological property of nasal cavity and surrounding tissue thereof.
A drug preparation for intranasal administration needs creative strategies because the clearance from nasal cavity is high. The preparation types for nasal cavity which have been developed include an ointment preparation, a droplet preparation, a spray-type preparation, a powder preparation, etc. These preparations are designed/developed so that an active medicament should effectively exert its effect in nasal cavity or be absorbed via the nasal cavity, i.e., the intranasal dispersibility of the preparations should be enhanced or the intranasal retention (adhesive property) should be enhanced, in order that the contacting time between an active medicament and nasal mucosa may be lengthened (JP-B-2011069).
An ointment preparation for nasal cavity is not so sanitary because it is usually put on with a finger, and additionally it is difficult to administer a predetermined amount of an active medicament because it is impossible to let the medicament reach the mucosa of deep nasal cavity with a finger.
A droplet preparation has been the most simple preparation for nasal cavity, however, it is difficult to accurately apply a predetermined amount thereof and further the applied medicament is removed from nasal cavity to pharynx through the mucociliary clearance.
A spray-type preparation is more dispersible than a droplet preparation because a liquid preparation can be pumped up, nebulized and intranasally sprayed.
A powder preparation is useful at the time of using a medicament decomposable in a solution or when the retention in nasal cavity should be held. However, the intranasal administration of a powder preparation might sometimes bring about some uncomfortable feelings and disorder of mucosa, and it is difficult to design a preparation having uniform particles.
Amongst these drug preparations for intranasal administration, a spray-type preparation is the most common preparation type because of its simplicity and comfortable feeling. On a spray-type preparation, some trials to enhance the efficacy and the absorption of a medicament have carried out by widening the contacting area between a medicament and nasal mucosa, and -lengthening the contacting time thereof, i.e., improving the retention of a medicament.
On conventional spray-type preparations, it is recommendable to suck air from nose at the time of the spray operation, in order to prevent holding a medicament at nasal vestibule or prevent the sprayed preparation from dripping off from nasal cavity. However, it is thought that the elastic tissue of nasal valve narrows by sucking air, and then almost all of the preparation is carried from nose to mouth and finally swallowed.
The liquid-spraying device which has been usually used in the past is made for a spray-type preparation for liquid formulation wherein a liquid formulation is pumped up through a tube, which is generally used at an angle between about 0-25° (see FIG. 3). For this device, it is necessary to put the tip of the tube in the liquid, and thus the spray angle of the spray container for administration needs to be set at around 0° and a patient needs to tilt his/her head forward, which is a reason for setting at an angle between about 0-25°. However, using this administration system, a normal liquid formulation which has no viscosity or no adhesion, or is low viscosity will instantly run to nostril. On the contrary, using this administration system as a patient tilts his/her head back and the spray angle of the spray container for administration is set at about 65-90°, a normal spray-type liquid preparation sprayed will be hit on the intranasal wall such as turbinate and nasal septum, and then drained to inferior meatus of nose because of its non-adhesion, and mostly ended up being carried to his/her mouth and swallowed. It is partially possible to prevent the liquid from running to inferior meatus of nose by adding an adhesive polymer mentioned later as a substrate of the formulation. However, when an adhesive polymer is used therein, it is thought that the particle size of the formulation sprayed gets bigger; the liquid cannot be widely dispersed since the spray spreading-angle from the spray container gets smaller; the particles collide with each other in a nose to get bigger particles which is hit on the wall; and many of the formulation end up being carried to a mouth and swallowed. Further, it is expected that the liquid can be spread at a wide area of the turbinate by spraying it with wider spray angle, however, thereby it becomes impossible to put the tip of the tube for pumping up in the liquid in case of a conventional spray-type preparation. Therefore, there was some limitations to administer a liquid formulation as a patient tilts his/her head back and the spray angle of the spray container for administration is set at a desired angle.
In addition, the above-mentioned spray device for liquid is a system absorbing external air and thus it is necessary to use a certain amount of an antiseptic agent or other agent.
In addition, the particle size sprayed from the spray device to nasal cavity is also one of the factors to be considered in order to improve the clearance of a medicament. That is to say, the nasal cavity of a human has an area of about 150-180 cm2, the distance from nostril to nasopharynx is 12-14 cm as a straight line which is very long, a nasal cavity has an optimized, narrow, and complicated geometric structure in order to protect the lower respiratory tract, and the narrow slit of the nasal valve causes about a half of the total air-resistance in nasal cavity. Further, there are some spaces partitioned in a slit like partition with turbinate in the backside of the nasal valve, where the speed of the formulation particles sprayed slows down and the particles can be contacted with nasal mucosa and dispersed. However, in such complicated and winding intranasal cavity, the formulation particles sprayed should been easily hit on the intranasal wall to be caught and deposited. Therefore, most of the formulation particles sprayed to nasal cavity whose particle size is 5 μm or more should be caught by the nasal cavity, then the formulation particles hit on the intranasal turbinate mucosa to be caught and deposited should be carried backward by means of the ciliary movement of ciliated cells covering the mucosa, and finally, via posterior nasal cavity and pharynx, drained to the month or swallowed. The countermeasure for the clearance of an active medicament which is taken as a foreign material by cilia and mucus (mucociliary clearance) is the most important factor on the design of a drug preparation for intranasal administration. The efficacy and the absorption of a medicament in nasal mucosa can be decided mainly based on the retention of a medicament (adhesive property of a formulation) and the permeability of a medicament at the capture part of nasal mucosa. A medicament administered to the effective capture part of nasal mucosa should disappear from the capture part as a simultaneous reaction mainly by means of the removal toward esophagus and respiratory tract due to the mucociliary clearance and the absorption to nasal mucosa cell via nasal mucosa. When the removal toward esophagus and respiratory tract from the effective capture part is quick, the clearance for the absorption to nasal mucosa cell should be reduced and the bioavailability thereof should be reduced. Or, the intranasal area which the formulation reaches can be improved to expand when the particle size of the sprayed formulation is micrified, however, thereby the risk that the formulation could reach lungs increases. Therefore, it has been understood for a skilled person to consider the balance of the particle size. Accordingly, in order to increase the clearance for the absorption to nasal mucosa and improve the absorption, it is important to optimize the particle size of the sprayed formulation, to spray in a suitable spray spreading-angle and an uniform spray spread, and further to add the retention of a medicament, i.e., adhesive property of a formulation for nasal mucosa, and thus it has been necessary to add an adhesive polymer as a base material for formulation to improve the property.
In theory, it is possible to spray a formulation for nose to take the formulation to the backside of the nasal valve by controlling the particle size of the sprayed formulation in a size of not more than 50 μm using a nebulizer, and inbreathing the sprayed particles at the time of spraying. However, using particles in a size of not more than 50 μm, a half or more of the particles should reach bronchi or lung, and thus a medicament to be held in intra cavity should disappear and additionally an undesirable side effect might happen. Further, the device for spray operation such as a nebulizer is expensive, and there was not any inexpensive and simple system to spread a formulation having an effective particle size in a whole intranasal cavity.
In order to improve the retention of a spray-type preparation in intranasal cavity, the present inventors have invented a gel base material for spray-administration to mucosa or skin, and have already disclosed a sprayable gel base material and a sprayable gel preparation comprising said base material and an active medicament, which can be applied to nasal cavity that is a mucosa site and is possible to use as a high-spreading spray-type preparation for nose (JP-B-2011069).
However, it has been already known as a serious problem that the viscosity should be reduced through spray operation even when a high viscous sprayable gel preparation is sprayed.
In addition, it is sometimes difficult to keep a constant amount of one spray shot when the spray angle for administration is rapidly changed, etc. because the sprayable gel-type preparation adheres on the sidewall of the spray container in being used as a spray-type preparation due to its high viscosity, the residual rate that indicates an unsprayed formulation retained in the container is high compared with a conventional liquid formulation, and the preparation cannot flow easily and rapidly in the spray container. Furthermore, it is also a problem that the formulation particles sprayed hardly reach the deep nasal cavity due to their particle size distribution, and it is difficult to adjust the spray spreading-angle and to spray in a uniform spray spread.
On a preparation for spray-administration to skin, there are also some similar problems to the above-mentioned preparation using a nasal spray such as the retention of the preparation, and the spray angle of the spray container for administration.

Sprayable gel-type skin/mucosa-adhesive preparation and administration system using the preparation


An improved aqueous slurry composition for the plasticizing of polyvinyl acetal resins whereby salts, acids and/or bases are used to enhance absorption rates of the plasticizer into the resin, and a process therewith for the production of plasticized polyvinyl acetal resins.

Laminated safety glass, such as used in vehicle windshields, is typically two mating sheets of glass bonded together with an interlayer of a thermoplastic material, such as polyvinyl butyral resin (PVB). When used as interlayer for safety glass, polyvinyl butyral resin is typically highly plasticized to make it soft and tacky. Laminated safety glass helps to protect from possible injury or other undesirable results of shattered glass resulting from forceful impacts. If safety glass is broken by impact, the interlayer remains substantially bonded to the broken glass, providing a form of protection from sharp and potentially dangerous shards. If in an accident an occupant is thrown into the windshield, the glass should yield somewhat to minimize impact injuries. Optimization between these two requirements requires careful control of the resin-to-glass adhesion. Adhesion that is too low may not provide an effective line of protections from shard. If adhesion is too high the unyielding windshield may worsen impact injuries. To achieve this control of adhesion, adhesion-limiting salts are typically added during the sheet forming extrusion step. Typical salts are alkali and alkaline earth salts, such as potassium or magnesium acetate, added in an amount sufficient to provide a cation concentration of about 100-500 mg/kg resin.
Plasticization of PVB is considered essential to its use in most types laminated safety glasses in which it is used. Plasticization of PVB can be accomplished by any number of known methods. For example, it is well known in the art to blend the plasticizer and the resin in a mixer, such as a Henschel or Banbury mixer, with subsequent extrusion compounding as described in U.S. Pat. No. 2,453,569. A solvent process, described by Haux in U.S. Pat. No. 2,046,378, used a C1 to C3 alcohol to introduce the plasticizer. Direct extrusion compounding is described in U.S. Pat. No. 5,886,075A. Another procedure is by absorption of the plasticizer into the resin from an aqueous slurry followed by a de-watering step and extrusion compounding.
In an aqueous slurry process, it has been found that different plasticizers are absorbed into the resin at different rates, thereby creating capacity and cost penalties. An aqueous slurry procedure has been described by Marks in U.S. Pat. No. 2,864,784, and describes the use of a stirred aqueous slurry of resin and an essentially water-insoluble plasticizer.
In the slurry process, the absorption rate of the plasticizer from the slurry into the resin is controlled by a number of parameters including ratio of solids (acetal resin and plasticizer) to water, plasticizing temperature, time, agitation speed and the like. The practical temperature range for aqueous plasticization as practiced in the prior art is from about 20° to 65° C. Due to the practical limitations of the conventional aqueous plasticization process, once a plasticizing system has been defined the only ways to increase capacity have been to add additional plasticizing vessels or increase agitation. Both of these options are costly and, in some instances, impractical due to structural limitations. The aqueous slurry process is also subject to significant variability in rate at which different plasticizers migrate into the resin.
After absorption of the plasticizer is complete, the plasticized resin is in the form of a plasticized slurry containing about 10% to about 25% solids (wet plasticized resin) and about 90% to about 75% of the aqueous phase. This slurry is first fed to a de-watering system that separates and removes 85-90% of the aqueous phase. The remaining aqueous phase, about 10% to about 15%, is entrained in the slurry solids that are forced into an extruder feed throat. This entrained water is removed by vacuum extraction in the extruder process. The extrudate is formed into sheeting by use of a slot sheeting die.
It is desirable to improve the process for the plasticization of polyvinyl butyral resins and to introduce adhesion-limiting salts in the process, thereby eliminating the subsequent separate step in which the adhesion-limiting salts must be added and thoroughly mixed. The present invention provides such a process.

Process for the aqueous plasticization of polyvinyl acetal resins