In the case of vehicle wheels the single-phase wobble may not exceed a certain maximum value if the vehicle is to satisfy certain demands of comfort. However, in this case it is of little use to measure the wobble of the vehicle brake disc and that of the vehicle hub carrying the said brake disc individually, because this is unable to give any statement concerning the wobble of the entire constructional unit.

The invention relates to a method for determining a wobble component due to a wheel hub of a vehicle and to a brake disc for carrying out this method.
On account of the increased demands for comfort, wheel brake discs of motor vehicles may only have a minimum wobble; a maximum of approximately 40 xcexcm at a diameter of 200 mm.
Greater wobbling of the brake disc leads to so-called brushing wear of the brake surface at the circumferential points of the greatest axial elevation of the brake disc during driving. At these circumferential points, the brake disc then has a changed surface texture in comparison with the other circumferential points, different frictional behaviour and a slight axial decrease in thickness. When actuated, this results in so-called brake juddering, i.e. a circumferentially synchronous, periodic fluctuation of the braking action.
In this connection, this depends less on the wobble of the isolated individual part than on that of the overall assembly comprising wheel bearings, hub inner contour, hub flange and brake disc. Due to the manufacturing process, each of these parts or contours is inherently provided with an unavoidable shape and measurement inaccuracy, these inaccuracies overriding one another in the assembly. The individual inaccuracies are dispersed statistically around an average value. The shape deviations are composed diversely of surface roughness, undulatory nature of the component and wobble. When a total wobble of x xcexcm is permitted at the assembly of the axle head, consisting overall of n parts together with the brake, theoretically, for each. individual part, a wobble of x/n maximum should be permitted. It ensues that the maximum permitted wobble of the brake disc applies to its outer circumference; a correspondingly smaller wobble, in accordance with the diameter ratio of brake disc to hub flange diameter, has to be prescribed in the case of a hub flange having a substantially smaller external diameter.
In this connection, wobble means an axial, sinoid positional deviation (single-phase wobble) which reproduces itself periodically during a single revolution of a component. The problem existing here is composed of a number of factors:
For one thing, the dimensional and shape deviations which are not of interest here, such as surface roughness and undulatory nature of the component, greatly override, with regard to their tolerable extent, the wobble which is actually of interest, with the result that the parameter which is of interest here cannot be isolated by measuring technology from a scanning record. The tolerable surface roughnesses and undulatory nature of the component are greater in their extent than the wobble which can be tolerated for an individual part.
Also, during the assembly, the parts become distorted, because of the joining force, in an extent of at least the same order of magnitude as the maximum permissible individual wobble for each component or component contour, i.e. even the component warpage due to assembly greatly overrides the wobble which is actually of interest.
Also, should it actually be possiblexe2x80x94for example, because of certain filter treatmentsxe2x80x94to isolate, using measurement technology, from a scanning record which is heavily overriden by signals which are not of interest, the single-phase wobble which is of interest here, it is nevertheless not possible to determine from this that component of the wobble which is attributed to the wheel hub.
Also, the factor in avoiding the brake juddering is for the wobble of the overall constructional unit to be as small as possible. In spite of keeping the wobble at the individual parts appropriately low, it may happen that during the assembly of the individual parts, an overall wobble is produced which is higher than the sum of the individual wobbling. Also the assembly of the individual parts itself therefore likewise generates a further wobble component which is dispersive in its effect.
Also, in order to be able to ensure the replaceability of the brake disc on its ownxe2x80x94as a wearing partxe2x80x94a constructional unit formed from a wheel hub and brake disc would not be able to be machined in respect of a slight wobble in the assembled state. In that case, when the worn brake disc is used, the wheel hub would also have to be renewed, which is to be avoided.
Also, in order to be able to draw nearer to a solution to the problem, there have to be ascertained from the overall wobble arising after the assembly of the individual parts, wobble components which can be unambiguously assigned to a specific component, for example the wheel hub. Only if the isolated wobble component of the wheel hub can be ascertained within the assembly unit using measuring technology can methods be sought as to how this wobble component can be reduced using manufacturing technology.
Measurement of the wobble is not new and is known, for example, from GB 2 159 276 A. However, this publication is concerned merely with the measuring of a brake disc, so that the specimens which lie outside the tolerance limits can be ejected. The determination of a wobble component due to the wheel hub of a vehicle wheel within a multi-part overall assembly is not provided there.
It has been disclosed by JP 1-28 5453 A to individually measure the wobble of a disc rotor and of an axle stub and then, on the basis of the measurements, to, undertake a rotational alignment of the two elements with the most favourable values (-so-called matching). However, this also has nothing to do with the problem addressed above.
DE 42 25 195 A1 discloses a method for measuring radial run-out and/or axial run-out deviations of a rotor, in which the rotor, which is held in a testing machine by means of a play-compensating clamping holder, is rotated while the rotation of the rotor is scanned in the region of its circumferential and/or side surfaces by contacting or contactless sensors and a radial run-out and/or axial run-out diagram is produced therefrom, two radial run-out or axial run-out diagrams, which are rotated through 180xc2x0 with respect to one another with regard to the clamping holder, being combined with one another and geometrical measurement errors, resulting from the clamping holder, in the two diagrams being compensated for in the radial run-out and axial run-out diagram obtained by the combination.
The object of the present invention is to provide a measurement method for determining a wobble component due to the wheel hub of a vehicle wheel within a multi-part overall assembly comprising wheel bearings, hub inner contour, hub flange and brake disc. The overall assembly can therefore be measured using a known measurement method, and this measurement should then enable the wobble component due to the wheel hub to be easily ascertained. This measurement method is suitable in practice in automotive engineering. Namely, the abovementioned brake juddering originates, as mentioned, not merely from the brake disc, but also from the overall assembly, for which reason there is little point in measuring and considering the brake disc in isolation. In addition, in the case of this overall assembly generally only the brake disc is the wearing part if the substantially longer service life of the wheel bearings is left out of the equation.
Accordingly, a quite essential point of this invention is the production and use of a master brake disc which is initially fastened, for measurement purposes, to the hub instead of the brake disc actually used in the vehicle. In this case, not only are all of its values, such as surface roughness, undulatory nature, evenness and wobble, as considered over the entire angular range of 360xc2x0, known, but moreover also a precise allocation of the xe2x80x9cerrorsxe2x80x9d, with regard to their phase position on this master brake disc is known. If, using this master brake disc, the measurement values of interest of the entire assembly are determined, the known values of the master brake disc can be subtracted from the determined values at a correct phase allocation, and a differential value is then obtained which can be expressed and which constitutes the wobble of the wheel hub. Of importance here is the design of the master brake disc, in particular the master brake disc may only have noticeably smaller errors than the values which are to be measured of the hub flange and the tolerance values of this components.
The advantages of the method according to the invention and of the associated master brake disc are the simple measurement means allowing the use of a wobble-measuring machine and measurement scanning-profile device. The measurement-assisting means used, namely the master brake disc, is, as the drawing shows, in conformity with the brake disc of the vehicle, a very simple element which can therefore also be produced very precisely. Simple measurement rules are sufficient and the measurement result can be reproduced by measuring technology. Finally, a clear assignment, by measuring technology, of the result to an isolated component is also achieved in the sought-after manner.

Method for determining a component-specific wobble component within a multi-part assembly of parts, and master part for carrying out the method

Abstract: With the aid of the method according to the invention, the wobble component, due to a wheel hub, of the constructional unit mentioned can be ascertained exactly if the precise data of the very precisely produced master brake disc, which is used in the measurement instead of the vehicle brake disc, is known.

Abstract: The method can only be carried out successfully using the master brake disc mentioned.


A detection apparatus is provided which includes a cantilever vibration gyro including a piezoelectric element having a first side provided with a drive electrode and a pair of detection electrodes sandwiching the drive electrode with predetermined gaps therebetween and a second side opposed to the first side and provided with a common electrode, which vibrates by a drive signal input between the drive electrode and the common electrode and generates a pair of detected signals corresponding to Coriolis force from the detection electrodes. The detection apparatus also includes a bias applying section for applying a bias voltage to the detection electrodes, an adding section adding the pair of detected signals, a first phase delay section delaying a phase of the detected signal obtained by the addition by a range larger than 45° and smaller than 90°, and an amplitude control section controlling the delayed detected signal to a predetermined voltage amplitude to output as the drive signal.

The present invention relates to a detection apparatus and method used for detecting an angular velocity of an object, and to an electronic apparatus equipped with the detection apparatus.
Up to now, so-called gyro detection apparatuses have been widely used as angular velocity sensors for consumer use. The gyro detection apparatuses are sensors that detect angular velocities by allowing a cantilever vibrator to vibrate at a predetermined resonance frequency and detecting Coriolis force generated due to an influence of the angular velocity by a piezoelectric element or the like.
The gyro detection apparatuses have advantages in that the sensors have a simple mechanism, require short time to activate, and can be manufactured at low costs. The gyro detection apparatuses are mounted to, for example, electronic apparatuses such as a video camera, a virtual reality apparatus, and a car navigation system, and are used as sensors in shake detection, motion detection, and direction detection, respectively.
In recent years, the gyro detection apparatuses are required to be downsized and improved in performance due to the downsizing and improvement in performance of the electronic apparatuses to which the gyro detection apparatuses are mounted. For example, because of multi-functionalization of the electronic apparatuses, demands are made to mount the gyro detection apparatus to a substrate in combination with various sensors for other purposes, thereby reducing a size thereof. A generally-used technique for realizing such reduction in size is called MEMS (Micro Electro Mechanical System) which involves using an Si substrate and forming a structural body using a thin-film process and a photolithography technique used in forming semiconductors.
Incidentally, a vibration system becomes light along with the downsizing of the gyro detection apparatus. However, because the Coriolis force is proportional to the weight of the vibration system, detection sensitivity deteriorates that much. Further, because amplitude of the vibrator becomes small when a power supply voltage is decreased due to the downsizing of the gyro detection apparatus, the detection sensitivity also deteriorates thereby. An S/N of a detection output signal is degraded by the deterioration of the detection sensitivity.
Thus, to solve the problems as described above, there is disclosed a technique in which drive signals having the same phase and amplitude and output from two detection electrodes are added in an adding circuit and the signal whose phase has been inverted in an inversion circuit is input to the two detection electrodes (see, for example, Japanese Patent Application Laid-open No. 2000-205861 (paragraphs (0005) and (0016), and FIG. 1)).
However, recently, further downsizing and reduction in voltage of a vibration gyro are required. Therefore, there is a need to further improve detection sensitivity of the vibration gyro and a need for suppressing noises to obtain a higher S/N than ever before.

Detection apparatus, detection method, and electronic apparatus


A microthruster having an inverted exhaust system traps burst diaphragm fragments providing a clean exhaust while an exhaust port provides increased back pressure for efficient combustion of a propellant charge in a fuel cell. A converging diverging micronozzle provides a predictable exhaust vector for improved microthrusting well suited for propulsion system on small spacecraft.

The invention relates to the field of micropropulsion systems and thrusters. More particularly, the invention relates to a microthruster having an encapsulated combustible fuel cell and an exhaust plenum for collecting debris during combustion of the fuel cell.
Propulsion systems have long been used in spacecraft. U.S. Pat. No. 4,840,024 issued Jun. 6, 1989 discloses a propulsion system, U.S. Pat. No. 5,924,278 issued Jul. 7, 1999 discloses a insulating nozzle thruster system, U.S. Pat. No. 4,318,028 discloses a gas nozzle thruster system. The advent of miniature satellites depends on the development of suitable micropropulsion systems. Solid propellant digital thrusters are currently under development. A pyrotechnic fuel charge is set off by a circuit at the bottom surface of the fuel charge. Solid propellants require elevated pressure for efficient and complete combustion. If such pressure is not built up and sustained during the burn, the resultant thrust is erratic, fragments of propellant as well as burst diaphragm are expelled randomly outward. Conventional solid rocket motors are designed to create a pressure increase upon ignition, and to expand the pressurized combustion gases through a converging diverging nozzle, to efficiently extract thrust from the propellant.
Microthruster propulsion systems have used combustible fuel cells that are selectively fired for propelling a spacecraft. The microthruster has an exhaust aligned in a single firing line directly from the fuel cells. The combustible fuel cells are covered with a fuel cap that is exploded outward thus ejecting uncontrolled debris in a single exhaust line directly away from the microthruster and the spacecraft. One problem associated with microthrusters is the exhaust of debris that provides variable microthrusting force vectors leading to an inability to accurately predict the force vector applied when firing a fuel cell. Another problem with the microthruster is the that the expelled debris may collect on sensitive spacecraft monitoring equipment and solar power collection systems thus disadvantageously contaminating spacecraft systems during a space mission. Previous designs of impulsive microthrusters include a reduced thickness section that bursts upon ignition of the charge or fuel cell by an ignition circuit. The ignition circuit is placed on the surface of the cell in an array of microthrusters each one individually addressable. The expulsion of propellant diaphragm debris fragments is caused by the back pressure at the ignition surface. The microthruster lacks a combustion chamber and can not provide increase controlled pressure for complete combustion. Consequently, the propellant is not completely burned, the burn conditions are variable and uncontrolled, and the debris and thrust vectors are erratic. These and other disadvantages are solved or reduced using the invention.
An object of the invention is to provide a microthruster with a clean exhaust.
Another object of the invention is to provide a microthruster with a predictable exhaust force vector when firing a combustible fuel cell.
Yet another object of the invention is to provide a microthruster with a combustible fuel in combination with a debris plenum for collecting debris remains during firing of the combustible cell for providing a clean exhaust and a predictable exhaust force vector.
A further object of the invention is to provide a microthruster with increase thrusting force by increasing combustion pressure.
Still a further object of the invention is to provide a microthruster with increased thrusting forces by increasing combustion pressure using a bent exhaust system.
The invention is directed to a microthruster having a combustible fuel cell coupled to a debris plenum surrounding an exhaust stream for collecting debris during firing of the combustible fuel so as to reduce the debris from the exhaust. The fuel cell is fired from an inverted side having a burst diaphragm that serves to encapsulate and ignite the combustible fuel cell. Upon firing, the diaphragm is exploded ejecting debris in an inverted direction and through a plenum serving to collect the debris. The exhaust is communicated through the exhaust system, including the plenum, serving to further increase the pressure within the combusting cell for increased exhaust thrust.
The solid propellant microthruster includes a propellant charge or fuel cell that is ignited by an ignition circuit. This ignition leads to the reduced likelihood of expelling propellant fragments, and improved burn area characteristics for more efficient combustion. The ignition circuit is mounted on a thin diaphragm that bursts upon ignition. The burst fragments are trapped in the plenum that allows combustion to progress and pressure to build up. The exhaust flow becomes lateral through one or more lateral ports and then the exhaust flow enters the converging diverging nozzle, and then the exhaust is finally expelled at the top surface of the microthruster with an appropriate expansion ratio and well defined thrust vector. A preferred folded flow design traps physical fragments of the burst diaphragm. A micromachined converging diverging micronozzle is achieved by specialized microprocessing to efficiently convert the pressure to flow and thrust. The exhaust flow path prevents expulsion of burst diaphragm fragments and flow is preferably passed through a micronozzle having a converging diverging profile for improved thrust efficiency. The thrust impulse is consistent in magnitude and direction and efficiently converts propellant energy to thrust.
The microthruster is suitable for replication during mass production for cost reduction. The microthruster design provides for ignition on a downstream surface of the propellant grain as in conventional solid motors. The microthruster controls the combustion pressure and achieves efficient combustion while being suitable for micromachining processes and materials during manufacturing. The microthruster is suitable for spacecraft microthrusting applications and for compact miniature gas generation systems for new generation inflatable space structures. The microthruster that can be replicated by mass production and micromachining methods with broad application in a wide variety of miniature spacecraft. These and other advantages will become more apparent from the following detailed description of the preferred embodiment.


A method for handling input/output (I/O) in a data storage system comprising a RAID subsystem storing data according to a RAID level utilizing a parity scheme, where RAID stripes have been configured across a plurality of data storage devices. The method may include monitoring write requests to the RAID subsystem, identifying write requests destined for the same RAID stripe, and bundling the identified write requests for substantially simultaneous execution at the corresponding RAID stripe. Monitoring write requests to the RAID subsystem may include delaying at least some of the write requests to the RAID subsystem so as to build-up a queue of write requests. In some embodiments, identifying write requests and bundling the identified write requests may include identifying and bundling a number of write requests as required to perform a full stripe write to the corresponding RAID stripe.

The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
Present information handling systems often take advantage of various data storage technologies, such as a redundant array of independent disks (RAID), which is a storage technology combining multiple disk or other drives into a logical storage unit. The use of RAID technology can improve data redundancy and performance. Data may be distributed across the drives in several ways, referred to as RAID levels. The RAID level utilized may depend on the specific level of redundancy and performance required. Each level provides a different balance between reliability, availability, performance, and capacity of the information handling system.
The endeavor for improved performance has led to the increased use of Flash based drives and other solid state devices. Yet, the characteristics of device wear for Flash based drives or other solid state systems (e.g., Flash memory has a relatively limited number of writes before wearing out) is changing the conventional assumptions of RAID levels generally made with respect to spinning disk drives. For example, smaller data allocations may generally be desirable for increasing or maximizing performance. On the other hand, large writes may be more desirable for decreasing or minimizing device wear with respect to solid state or Flash drives.
Some conventional caching technologies attempt to solve a portion of this problem by concatenating multiple writes together. However, there remains a need for further improvement in the performance and durability of information handling systems utilizing or incorporating Flash based or other solid state devices, or generally in the handling of I/O in all information handling systems.

I/O handling between virtualization and raid storage


For enhancing engine startability and reducing discharge of unburned fuel from an engine, a camshaft is rotated toward the most advance side when an exhaust valve is opened. In one aspect, the camshaft is urged toward the advance side with respect to a timing pulley by the urging force of a spring. A stopper is received displaceably in a diametrical direction in a receiving hole and is fitted in a stopper hole when the camshaft is at the most advance position. In another aspect, at engine starting where operating fluid is not supplied to a release fluid chamber, a clutch piston is coupled to a front plate by a spring, and gear teeth of the front plate and the clutch piston are engaged with each other.

1. Field of the Invention
The present invention relates to a valve timing regulation apparatus for an internal combustion engine for regulating opening or closing timing of an intake valve or an exhaust valve of an internal combustion engine.
2. Description of Related Art
In a conventional valve timing regulation apparatus for regulating opening or closing timing (valve timing) of an intake valve or an exhaust valve of an internal combustion engine, drive torque is transmitted from a crankshaft as a drive shaft of the engine to a camshaft as a driven shaft through a drive force transmission member. As the drive force transmission member, for example, a ring-like gear or a vane is employed.
The ring-like gear is engaged with a timing pulley and a spline of the camshaft. At least one of those is engaged with a helical spline. The ring-like gear is moved in an axial direction by fluid pressure whereby the camshaft and the timing pulley are relatively rotated to regulate the valve timing of the intake valve or the exhaust valve according to operating conditions of the engine.
Further, in the vane system disclosed in Japanese Patent Laid-Open No. Hei-1-92504, a housing rotated along with the timing pulley houses therein a vane rotated along with the camshaft. The relative rotation phase difference of the vane with respect to the housing is regulated by fluid pressure to thereby relatively rotate the camshaft and the timing pulley so that the valve timing of the exhaust valve is regulated according to the operating conditions of the engine.
However, in the above conventional valve timing regulating apparatus, the camshaft as the driven shaft receives the force on the retard side with respect to the drive shaft by the drive torque applied to the camshaft for opening and closing the exhaust valve. Accordingly, when the fluid pressure does not operate such as when the engine starts, and at the time of low oil pressure such as when it is idling, the opening timing of the exhaust valve is retarded to sometime overlap the opening timing of the exhaust valve and the opening timing of an intake valve. When the opening timings of the exhaust valve and the intake valve overlap, the combustion gases remained in the cylinder of the engine, i.e., internal exhaust gas recirculation (EGR) amount becomes excessively large, and as a result, the startability of the engine becomes deteriorated, and the engine sometimes becomes disabled to start. Further, there is a problem that the unburned fuel is discharged into exhaust gases.
Further, in the case where the phase difference is regulated by fluid pressure, for example, when the number of revolutions of the engine is low and the discharge pressure of a fluid pump is low, the camshaft cannot be moved toward the advance side with respect to the crankshaft, sometimes resulting in disablement of regulation of the valve timing. Also in the case of the low fluid pressure as described, it is contemplated that a pressure receiving area of fluid pressure is increased to render the regulation of the valve timing possible. However, even if the valve timing can be regulated with low fluid pressure, in the case where the discharge amount and discharge pressure of the fluid pump are sufficient with high rotation of the engine, the flow rate of the operating fluid increases and the time required to change the valve timing increases. That is, a problem arises in that the responsiveness lowers. Further, a problem arises in that the size of the apparatus increases. Further, when the operating fluid pressure is lowered due to the trouble of the fluid pump or the like, the valve timing cannot be regulated, and the engine may be stopped.
Still further, it is necessary to advance the camshaft with respect to the crankshaft at the time of start of the engine and at the time of low load. However, when the camshaft is retarded with respect to the optimum valve timing, the period at which both the exhaust valve and the intake valve are opened increases due to the low rotation and the trouble of the exhaust valve. Then, the exhaust gas remains within the combustion chamber so that the necessary amount of air is not taken into the combustion chamber and the exhaust gas is reversed on the intake side. Further there occurs a problem in that the unburned gas is discharged into the exhaust gas.
As a result, the combustion gas, i.e., internal EGR amount remained in the cylinder of the engine becomes excessively large whereby the combustion is unstable, the noxious component amount contained in the exhaust gas increases, and in the extreme case, the engine stops. At the time of start of the engine, startability becomes worsened.

Valve timing regulation apparatus for engine


A pixel array substrate with new pixel design and a liquid crystal display panel with the pixel array substrate are provided. The pixel array substrate includes a plurality of data lines, a plurality of scan lines and a plurality of pixels. Each of the pixels comprises a first electrode, a first connecting line, a second electrode and a second connecting line. The first electrode is electrically connected with corresponding data line and scan line through the first connecting line, and having a slit. The second pixel is electrically connected with corresponding data line and scan line through the second connecting line. At least a part of the second connecting line is exposed by the slit of the first electrode.

Technical Field
The present disclosure relates to a substrate, and more particularly, to a pixel array substrate of a display panel.
Description of Related Art
Liquid crystal display (LCD) panels have become the mainstream display products because of advantages such as low radiation, low power consumption and compact size. A variety of techniques in the LCD panels are developed corresponding to different needs. Among which, Vertical Alignment (VA) of the wide viewing angle display technology has wider viewing angle than that of Twisted Nematic (TN), fast responding, and high contrast ratio, thus has been widely applied in a LCD panel.
However, the VA LCD panel is known for its color washout issue. To solve the issue, the pixel area of the pixel array substrate of current VA LCD panels is divided into two parts. As illustrated in FIG. 1 and FIG. 2, FIG. 1 is a top-view of the conventional pixel, and FIG. 2 is the equivalent circuit diagram of the pixel illustrated in FIG. 1. Referring to FIG. 1 and FIG. 2, pixel 100 includes a first pixel electrode 102, a second pixel electrode 104, a first connecting line 106, and a second connecting line 108. The first electrode 102 is electrically connected to its corresponding data line DL1 and scan line SL1 through the first connecting line 106 and the a switch T1; The second pixel electrode 104 is also electrically connected to its corresponding data line DL1 and scan line SL1 through the second connecting line 108 and a switch T2. In addition, pixel 100 also includes a switch T3, storage capacitors CST1, CST2, common electrode VCOM, liquid crystal capacitors CLC1, CLC2, and charge-sharing capacitor Cs (CCSA and CCSB). Switches T1, T2, and T3 are thin-film transistors (TFT), for example. Liquid crystal capacitors CLC1, CLC2 respectively represent the capacitances which are generated between pixel electrode (the first pixel electrode 102 and the second pixel electrode 104) and the electrode(s) applied with VCOM voltage on the opposite substrate of the LCD panel (not illustrated in FIG. 1 and FIG. 2). CST1 and CST2 respectively represent the capacitances which are generated between common electrode applied with VCOM voltage and each pixel electrode (the first pixel electrode 102 and the second pixel electrode 104) of the pixel array substrate of the LCD panel. Charge-sharing capacitor Cs is an extension from the switch T3, charge-sharing capacitor Cs forms capacitors with other conductive layers, for example, CCSA is the capacitor formed between the first pixel electrode 102 and Cs, and CCSB is the capacitor formed between the common electrode VCOM and Cs.
As to the main display area which corresponds to the first pixel electrode 102, the switch T1 is electrically connected between data line DL1 and the first pixel electrode 102. The switch T1 is also electrically connected to scan line SL1, and a signal passing through scan line SL1 controls the switch T1 to turn on/off. The storage capacitor CST1 is electrically connected between the first pixel electrode 102 and the common electrode VCOM. When the switch T1 turns on, a data signal of data line DL1 is transmitted through the switch T1 to the first electrode 102, so that the storage capacitor CST1, is charged to have corresponding voltage.
As to the secondary display area which is corresponding to the second pixel electrode 104, the switch T2 is electrically connected between data line DL1 and the second pixel electrode 104. The switch T2 is also electrically connected to scan line SL1, a signal passing through scan line SL1 controls the switch T2 to turn on/off. The storage capacitor CST2 is electrically connected between the second pixel electrode 104 and the common electrode VCOM. When the switch T2 turns on, a data signal of data line DL1 is transmitted through the switch T2 to the second electrode 104, so that the storage capacitor CST2 is charged to have corresponding voltage. To solve the issue of color washout of the LCD panel, charge sharing is performed. After the first pixel electrode 102 and the second pixel electrode 104 are charged by the signal from scan line SL1, in next time sequence, the switch T3 turns on by the signal inputted from scan line T3, so as a part of the voltage of the second pixel electrode 104 is shared to the capacitor CCSB and the other part of the voltage of the second pixel electrode 104 is shared to the capacitor CCSA through the switch T3. It results in charge sharing between the first pixel electrode 102 and the second pixel electrode 104 by the charge-sharing capacitor Cs, the voltage of the first pixel electrode 102 increases and that of the second pixel electrode 104 decreases. Therefore, the voltages of the first pixel electrode 102 and the second pixel electrode 104 are different. It causes the tilting angle of liquid crystals corresponding to the first pixel electrode 102 and the second pixel electrode 104 are different within the same pixel 100, so as the brightness within the same pixel 100 can be optimized since the transmittance within the same pixel 100 can be different, thus the issue of color washout can be solved.
However, continually referring FIG. 1 and FIG. 2, as illustrated in dot lines area of FIG. 1, in the path of the second connecting line 108 connecting to the second pixel electrode 104, part of the path is underpass the first pixel electrode 102. This overlapping structure of the second connecting line 108 and the first pixel electrode 102 in vertical direction will generate an extra coupling capacitance Cx as illustrated in dot lines area of FIG. 2. When the coupling capacitance Cx is generated between the first pixel electrode 102 and the second pixel electrode 104, charge sharing will be weaken. Thus the effects of the voltage increase of the first pixel electrode 102 and the voltage decrease of the second pixel electrode 104 are diminished. Therefore, to increase the voltage difference between the first pixel electrode 102 and the second pixel electrode 104 becomes difficult. In order to maintain the voltage difference between the first pixel electrode 102 and the second pixel electrode 104 to solve the color washout issue, further increase the capacitance of the charge-sharing capacitor Cs to release more electric charge from the second pixel electrode 104 and lower the voltage of the second pixel electrode 104 is generally performed. However, the efficiency of the LCD panel is decreased to maintain the voltage difference between the first pixel electrode 102 and the second pixel electrode 104 in this way.

Pixel array substrate and liquid crystal display panel


A blast hole liner is provided having an outer sleeve and an elongate tubing located within the outer sleeve. The outer sleeve is provided with an open first end thereby forming an internal space, adapted to hold an explosive composition. The outer sleeve also has at least one compartment 5 formed in a second end. The elongate tubing is adapted to allow for the entry of compressed air to inflate the elongate tubing and thereby ensure straightening or untwisting of the outer sleeve.

In mining applications explosive compositions often need to be placed in drilled blast holes in defined depths and amounts. This helps ensure that the blast rock is broken down in the desired manner leaving rubble and muck pile or fragmentation which is as large as is manageable for more efficient and economical removal.
A blast hole liner may often be used, especially with costly emulsion explosives, to line the blast hole and they often take the form of a simple polymer tubing. The tubing can come in an array of lengths to suit blast holes of differing depths although many are only guaranteed up to 40 m depth in water-filled blast holes for reasons discussed below. The liner prevents the loss of explosives into cracks and fissures in the rock prior to blasting and protects the explosive from the ingress of water. Water can obviously dilute the explosive, necessitating adjustment for this factor, reduce the blast outcome and, in the case of dynamic water, can result in significant and costly loss of explosive.
The liner will therefore encapsulate the explosive composition and protect it from loss and external water ingress. This approach also opens up the possibility of using a lower cost ANFO mix instead of emulsion explosives under certain circumstances.
In use, the liner is typically located on a yolk extending from a truck and dirt or stemming will be added into a lower portion of the liner as weighting to drop the liner to a sufficient depth in the water-filled blast hole. When sufficient stemming is judged by the operator to have been added then that bottom section is sealed, typically by a simple cable tie, to retain the stemming. A further seal above the stemming is also generated on site to keep the stemming separate from the explosives which will be subsequently added. Often this seal is entirely inadequate and so a significant quantity of water can enter the liner upon introduction into a water-filled borehole.
Upon lowering the liner into the blast hole, a common difficulty is the twisting of the liner which can lead to constrictions and knots within portions of the liner. Some prior art liners are concertinaed in an attempt to address this but the reality is that twisting and knotting is still a significant problem. This can effectively shorten the length of the liner available for containing the explosives. In certain situations, it may be that the weight of a detonator dropped into the liner means it finds its way through any constricted section of the liner but the subsequently added explosives do not. This can result in a separation of detonator and explosives and so a misfire in the blast hole. Attempting to realign the twisting of the liner on site can be a time-consuming exercise.
A further challenge is achieving just the right amount of stemming in the liner for an appropriate level of ballast. When ANFO is used, due to its lower density, it tends to float in water and so if insufficient stemming is added initially, then it can be difficult to lower the liner to the required depth. This can be especially challenging when lowering to depths greater than 40 m. Removal of the liner from the blast hole when filled with explosives, to alter the ballast, is generally either not possible or at least highly undesirable.
It would therefore be desirable to have a blast hole liner which addresses one or more of these drawbacks or at least provides the consumer with a useful commercial alternative.


A superconducting magnet arrangement (M, S, P1, . . . , Pn) for generating a magnetic field in the direction of a z axis in a working volume, disposed about z=0, comprising a magnet coil system (M) with at least one current-carrying superconducting magnet coil, a shim device (S) with at least one superconducting shim coil and additional superconductingly closed current paths (P1, . . . , Pn), wherein the magnetic fields generated in the z direction and in the working volume by the additional current paths due to induced currents during operation, do not exceed a magnitude of 0.1 Tesla, and wherein the shim device generates a field which varies along the z axis with a kth power of z for an even power of k greater than 0, is characterized in that the shim device is designed such that the effective field efficiency gSeff of the shim device is substantially zero taking into consideration the diamagnetism of the superconductor in the magnet coil system.

This application claims Paris Convention priority of DE 100 41 683.7 filed Aug. 24, 2000 the complete disclosure of which is hereby incorporated by reference.
The invention concerns a superconducting magnet arrangement for generating a magnetic field in the direction of a z axis in a working volume disposed about z=0, with a magnet coil system having at least one current-carrying superconducting magnet coil, a shim device with at least one superconducting shim coil and one or several additional superconductingly closed current paths, wherein the magnetic fields in the z direction produced by induced currents through the additional current paths during operation do not exceed a magnitude of 0.1 Tesla in the working volume, and wherein the shim device generates a field which varies along the z axis with the kth power of z for an even power of k greater than 0.
A superconducting magnet arrangement with a Z2 shim device of this type is part of e.g. the NMR Magnet System 600 SB UltraShield(trademark) (company leaflet dated May 15, 1999) distributed by the company Bruker Magnetics.
U.S. Pat. No. 5,329,266 describes a superconducting magnet arrangement with an actively shielded magnet and additional superconducting current paths without a Z2 shim device.
Superconducting magnets are used for different applications, in particular for magnetic resonance methods, in which the local homogeneity of the magnetic field is usually important. One of the most demanding applications is high-resolution nuclear magnetic resonance spectroscopy (NMR spectroscopy). The basic homogeneity of the superconducting magnet can be optimized through the geometrical arrangement of the field-generating magnet coils. In demanding applications, the basic homogeneity of the magnet is usually insufficient due to deviations from the design caused by production tolerances. To compensate for residual inhomogeneities of the magnet, the magnet system is equipped with autonomous superconducting coils which compensate for field inhomogeneities having a certain geometrical symmetry in the working volume, so-called shim devices. Examples of such shim devices are so-called Zn shims which produce a field which varies along the magnet axis z as zn. The main focus of the invention is the dimensioning of superconducting Zn shims in magnet systems with active stray field shielding and additional superconducting current paths, e.g. to compensate for external field fluctuations.
The field contribution of a superconducting Zn shim in a working volume must be substantially zero in the working volume at z=0, irrespective of the current in the shim coils, thereby taking into consideration the field contributions of the shim coils themselves and also of the field change due to currents induced in the superconducting magnet and in further superconductingly closed current paths during charging of the shim device. Dimensioning of a Zn shim according to a conventional method will produce, in certain cases, an undesired shift of the magnetic field strength in the working volume at z=0 during charging of the shim device. In actively shielded magnets, this behavior is particularly clear with shim devices whose coils are distributed over different radii because the conventional methods for dimensioning superconducting shim devices treat the superconductor as a non-magnetic material. The present invention also takes into consideration that the superconductor substantially exhibits a diamagnetic material behavior in response to field fluctuations of less than 0.1 Tesla, which can e.g. occur in the magnet volume during charging of a superconducting shim device, and thereby largely expels small field fluctuations from its inner regions. This results in a redistribution of the magnetic flux of the field fluctuations in the magnet arrangement which, in turn, influences the reaction of the superconducting magnet and further superconductingly closed current paths to a current change in the shim device, since this reaction is determined by the principle of magnetic flux conservation through a closed superconducting loop.
In contrast thereto, it is the underlying purpose of the present invention to modify a superconducting Zn shim in a magnet arrangement of the above-mentioned type in as simple a manner as possible such that the shim device is correctly dimensioned while taking into consideration the diamagnetism of the superconductor such that, in particular, its field contribution in the working volume is substantially zero in the working volume at z=0, irrespective of the current in the shim coils.
This object is achieved in accordance with the invention by designing the shim device such that the variable gSeff=gSxe2x88x92gTxc2x7(Lclxe2x88x92xcex1Lcor)xe2x88x921xc2x7(L←Sclxe2x88x92xcex1L←Scor) is substantially zero if and only if the variable gSeff,cl=gSxe2x88x92gTxc2x7(Lcl)xe2x88x921xc2x7L←Scl, which would have resulted were xcex1=0, is larger than zero, in particular larger than 0.2 millitesla per ampere.
The above variables have the following definitions:
gSeff: Field contribution per ampere current of the shim device in the working volume at z=0 thereby taking into consideration the field contributions of the shim coils themselves and of the field change due to currents induced in the superconducting magnet coil system and in the further superconductingly short-circuited current paths during charging of the shim device,
xe2x88x92xcex1: average magnetic susceptibility in the volume of the magnet coil system with respect to field fluctuations which do not exceed a magnitude of 0.1 T, wherein 0 less than xcex1xe2x89xa61,
gT=(gM, gP1, . . . , gPj, . . . , gPn),
gPj: Field per ampere of a current path Pj in the working volume without the field contributions of current paths Pi for ixe2x89xa0j and of the magnet coil system and without the field contributions of the shim device,
gM: Field per ampere of the magnet coil system in the working volume without the field contributions of the additional current paths and without the field contributions of the shim device,
gS: Field per ampere of the shim device in the working volume without the field contributions of the additional current paths and of the magnet coil system,
Lcl: Matrix of inductive couplings between the magnet coil system and the additional current paths and among the additional current paths,
Lcor: Correction for the inductance matrix Lcl, which would result with complete diamagnetic expulsion of disturbing fields from the volume of the magnet coil system,
L←Scl: Vector of the inductive couplings of the shim device with the magnet coil system and the additional current paths,
L←Scor: Correction for the coupling vector L←Scl, which would result for complete diamagnetic expulsion of disturbance fields from the volume of the magnet coil system.
According to prior art, correct dimensioning of a Zn shim entails correct calculation of the field efficiencies gS, gp1, . . . , gPn and gM of the shim device, of the additional superconducting current paths and of the magnet (without taking into consideration the respective reactions of the other components) and the mutual inductive couplings among the shim device, the additional current paths and the magnet as well as all self-inductances, wherein the shim device is then designed such that the variable gSeff,cl=gSxe2x88x92gTxc2x7(Lcl)xe2x88x921xc2x7L←Scl is substantially zero. When dimensioning the shim device of an arrangement in accordance with the invention, in addition to the above-mentioned coil properties, the magnetic shielding behavior of the superconducting volume portion of the magnet coil system is also taken into consideration. For this reason, the shim device is dimensioned such that instead of the variable gSeff,cl the variable gSeff=gSxe2x88x92gTxc2x7(Lclxe2x88x92xcex1Lcor)xe2x88x921xc2x7(L←Sclxe2x88x92xcex1L←Scor) is substantially zero. The above-mentioned magnetic shielding behavior of the superconductor is present in all superconducting magnet arrangements, but only has significant effect on the variable gSeff in certain cases. The present invention is advantageous in that such magnet arrangements also satisfy the requirement for the shim device that gSeff be substantially zero.
The above-mentioned advantages of the invention are significant mainly in systems where the local homogeneity of the magnetic field in the working volume is particularly important. In one preferred embodiment, the inventive magnet arrangement is therefore part of an apparatus for high-resolution magnetic resonance spectroscopy, e.g. in the field of NMR, ICR or MRI.
In an advantageous further development of this embodiment, the magnetic resonance apparatus comprises a means for field locking the magnetic field generated in the working volume.
In an improved further development, the magnet arrangement can also comprise field modulation coils.
One embodiment of the inventive magnet arrangement is particularly preferred, wherein the superconducting magnet coil system comprises a radially inner and a radially outer coaxial coil system which are electrically connected in series, wherein these two coil systems each generate one magnetic field of mutually opposite direction along the z axis in the working volume. In such an arrangement, the diamagnetic shielding behavior of the superconductor typically has a particularly strong effect on the effective field strength in the working volume gSeff of certain shim devices in the magnet coil system.
In a further development of this embodiment, the radially inner coil system and the radially outer coil system have dipole moments approximately equal in value and opposite in sign. This is the condition for optimum suppression of the stray field of the magnet coil system. Due to the great technical importance of actively shielded magnets, the correct dimensioning of shim devices in magnets, wherein the above-mentioned magnetic shielding behavior of the superconductor in the magnet coil system has significant influence on the effective field strength in the working volume gSeff of the shim device, is particularly advantageous.
In another advantageous further development of one of the above embodiments, the magnet coil system forms a first current path which is superconductingly short-circuited during operation, and a disturbance compensation coil which is not galvanically connected to the magnet coil system is disposed coaxially to the magnet coil system and forms a further current path which is superconductingly short-circuited during operation. The presence of a disturbance compensation coil improves the temporal stability of the magnetic field in the working volume under the influence of external field fluctuations. Such a further development of an inventive magnet arrangement takes into consideration the influence of a disturbance compensation coil on the effective field strength in the working volume gSeff of the shim device.
In one further advantageous development, at least one of the additional current paths consists of a part of the magnet coil system which is bridged with a superconducting switch. Such an arrangement improves the temporal stability of the magnetic field in the working volume under the influence of external field fluctuations. Such a further development of an inventive magnet arrangement takes into consideration the influence of bridging part of the magnet coil system with a superconducting switch on the effective field strength in the working volume gSeff of the shim device.
In an advantageous further development of the inventive magnet arrangement, at least one of the additional current paths is part of a system for compensating the drift of the magnetic coil system. Such an arrangement improves the temporal stability of the magnetic field in the working volume. Such a further development of an inventive magnet arrangement takes into consideration the influence of drift compensation on the effective field strength in the working volume gSeff of the shim device.
In one further advantageous development, at least one of the additional current paths consists of a further superconducting shim device. Such an arrangement compensates for field inhomogeneities which have different symmetries. Such a further development of an inventive magnet arrangement takes into consideration the influence of the additional superconducting shim devices on the effective field strength in the working volume gSeff of the first shim device.
One particularly preferred embodiment of the inventive magnet arrangement is characterized in that the superconducting shim device produces a field in the working volume having a z2 dependence along the z axis. Such shim devices are particularly important since superconducting magnet coil systems often have a field inhomogeneity which has a z2 dependence along the z axis in the working volume.
In a particularly advantageous further development of this magnet arrangement, the superconducting shim device comprises partial coils which are wound at different radii to permit a more compact construction of the shim device. The magnetic shielding behavior of the superconductor in the magnet coil system of such an arrangement typically has a particularly strong effect on the effective field strength in the working volume gSeff of the shim device.
Another advantageous further development of an inventive magnet arrangement is characterized in that the superconducting shim device is inductively decoupled from the superconducting magnet coil system to prevent high induced currents in the shim device during charging or during a quench of the superconducting magnet coil system.
An advantageous further development of this embodiment utilizes the different polarities of the radially inner and the radially outer coil system for inductive decoupling of the magnet coil system and shim device, wherein the superconducting magnet coil system has a radially inner and a radially outer coaxial coil system which are electrically connected in series, with these two coil systems each generating one magnetic field of mutually opposing directions along the z axis in the working volume. Utilization of the different polarities of the radially inner and radially outer coil system facilitates design of the magnet arrangement in accordance with the above-described embodiment.
The present invention also comprises a method for dimensioning a shim device which is characterized in that the variable gSeff, which corresponds to the field change in the working volume at z=0 per ampere current in the shim device, is calculated, taking into consideration the magnetic fields generated due to the currents induced in the residual magnet arrangement, according to:
gSeff=gSxe2x88x92gTxc2x7(Lclxe2x88x92xcex1Lcor)xe2x88x921xc2x7(L←Sclxe2x88x92xcex1L←Scor),
wherein these variables have the above-mentioned definitions. This method for dimensioning a shim device advantageously takes the magnetic shielding behavior of the superconductor in the magnet coil system into consideration. This method permits dimensioning of all embodiments of the invention through calculation of the behavior of the magnet system during charging of the shim device thereby taking into consideration the current changes induced in the magnet coil system and in the additional current paths. This method is based on the calculation of correction terms for the inductive couplings among the additional current paths, with the magnet coil system and with the shim device and for all self-inductances, which influence the corresponding quantities with a weighting factor xcex1. This method improves the correspondence between calculated and measurable field strength in the working volume gSeff of the shim device compared to a conventional method. In particular, gSeff can be made substantially zero.
In a simple variant of the inventive method, the parameter a corresponds to the volume portion of the superconductor material with respect to the coil volume of the magnet coil system. This method for determining the parameter xcex1 is based on the assumption that the superconductor has a susceptibility with respect to field fluctuations of (xe2x88x921) (ideal diamagnetism).
The values for xcex1 determined in this fashion cannot be experimentally confirmed for most magnet types. A particularly preferred alternative method variant is therefore characterized in that the parameter a for the magnet coil system is experimentally determined from the measurement of the variable       β    exp    =            g      D      exp              g      D
of the magnet coil system, with no additional current paths present, in response to a disturbance coil generating a substantially homogeneous disturbance field in the volume of the magnet coil system, and through insertion of the variable xcex2exp into the equation       α    =                                                      g              D                                                  (                              L                M                cl                            )                                2                                  (                                    β              exp                        -                          β              cl                                )                                                                g              D                                                  (                                                β                  exp                                -                                  β                  cl                                            )                                                      L            M            cl                                          L            M            cor                          -                              g            M                                          (                                                            L                                      M                    ←                    D                                    cl                                                                  L                  M                  cor                                            -                                                L                                      M                    ←                    D                                    cor                                                                  L                  M                  cl                                                      )                                ,
wherein
gDexp: measured field change in the working volume of the magnet arrangement per ampere current in the disturbance coil,             β      cl        =          1      -                        g          M                ·                  (                                    L                              M                ←                D                            cl                                                      L                M                cl                            ·                              g                D                                              )                      ,
gM: Field per ampere of the magnet coil system in the working volume,
gD: Field per ampere of the disturbance coil in the working volume without the field contributions of the magnet coil system,
LMcl: Self inductance of the magnet coil system,
LM←Dcl: Inductive coupling of the disturbance coil with the magnet coil system,
LMcor: Correction for the self inductance LMcl of the magnet coil system, which would result for complete diamagnetic expulsion of disturbance fields from the volume of the magnet coil system,
LM←Dcor: Correction for the inductive coupling LM←Dcl of the disturbance coil with the magnet coil system which would result for complete diamagnetic expulsion of disturbance fields from the volume of the magnet coil system.
Finally, in a further particularly preferred variant of the inventive method, the corrections Lcor, L←Scor, LMcor and LM←Scor are calculated as follows:             L      cor        =          (                                                  L              M              cor                                                          L                              M                ←                P1                            cor                                            …                                              L                              M                ←                Pn                            cor                                                                          L                              P1                ←                M                            cor                                                          L              P1              cor                                            …                                              L                              P1                ←                Pn                            cor                                                            ⋮                                ⋮                                ⋰                                ⋮                                                              L                              Pn                ←                M                            cor                                                          L                              Pn                ←                P1                            cor                                            …                                              L              Pn              cor                                          )        ,
                L              ←        S            cor        =          (                                                  L                              M                ←                S                            cor                                                                          L                              P1                ←                S                            cor                                                            ⋮                                                              L                              Pn                ←                S                            cor                                          )        ,xe2x80x83LPj←Pkcor=fPj(LPj,red,Ra1)←Pkclxe2x88x92L(Pj,red,Ri1)←Pkcl),
LPj←Scor=fPj(LPj,red,Ra1)←Sclxe2x88x92L(Pj,red,Ri1)←Scl),
LPj←Mcor=fPj(LPj,red,Ra1)←Mclxe2x88x92L(Pj,red,Ri1)←Mcl),
            L              M        ←        Pj            cor        =                  L                  1          ←          Pj                cl            -              L                              (                          1              ,              red              ,                              Ri                1                                      )                    ←          Pj                cl            +                                    Ra            1                                R            2                                            (                                    L                                                (                                      2                    ,                    red                    ,                                          Ra                      1                                                        )                                ←                Pj                            cl                        -                          L                                                (                                      2                    ,                    red                    ,                                          Ri                      1                                                        )                                ←                Pj                            cl                                )                      ,
                L              M        ←        S            cor        =                  L                  1          ←          S                cl            -              L                              (                          1              ,              red              ,              Ri1                        )                    ←          S                cl            +                                    Ra            1                                R            2                                            (                                    L                                                (                                      2                    ,                    red                    ,                                          Ra                      1                                                        )                                ←                S                            cl                        -                          L                                                (                                      2                    ,                    red                    ,                                          Ri                      1                                                        )                                ←                S                            cl                                )                      ,
                L      M      cor        =                  L                  1          ←          1                cl            -              L                              (                          1              ,              red              ,              Ri1                        )                    ←          1                cl            +              L                  1          ←          2                cl            -              L                              (                          1              ,              red              ,              Ri1                        )                    ←          2                cl            +                                    Ra            1                                R            2                                            (                                    L                                                (                                      2                    ,                    red                    ,                                          Ra                      1                                                        )                                ←                2                            cl                        -                          L                                                (                                      2                    ,                    red                    ,                                          Ri                      1                                                        )                                ←                2                            cl                        +                          L                                                (                                      2                    ,                    red                    ,                                          Ra                      1                                                        )                                ←                1                            cl                        -                          L                                                (                                      2                    ,                    red                    ,                                          Ri                      1                                                        )                                ←                1                            cl                                )
wherein
Ra1: Outer radius of the magnet coil system (in case of an actively shielded magnet coil system, the outer radius of the main coil),
Ri1: Inner radius of the magnet coil system,
R2: in the case of an actively shielded magnet coil system, the average radius of the shielding, otherwise infinite,
RPj: average radius of the additional coil Pj,       f    Pj    =      {                                                                      Ra                1                                            R                Pj                                      ,                                          R                Pj                             greater than                               Ra                1                                                                                1            ,                                          R                Pj                             less than                               Ra                1
and wherein the index 1 represents the main coil of an actively shielded magnet coil system, otherwise the magnet coil system, and the index 2 represents the shielding of an actively shielded magnet coil system, and otherwise terms of index 2 are omitted, and the index (X,red,R) designates a hypothetical coil having all windings of a coil X at the radius R.
The particular advantage of this method for calculating the corrections Lcor, L←Scor, LMcor and LM←Scor consists in that the corrections are derived from inductive couplings and self-inductances of coils thereby taking into consideration the geometric arrangement of the coils concerned.
Further advantages of the invention can be extracted from the description and the drawing. The features mentioned above and below can be used in accordance with the invention either individually or collectively in any arbitrary combination. The embodiments shown and described are not to be understood as exhaustive enumeration but rather have exemplary character for describing the invention.
The invention is shown in the drawing and explained in more detail with respect to embodiments.

Dimensioning of a superconducting shim device in a superconducting magnet arrangement


Dental composite filler materials comprise particles coated via an atomic layer deposition (ALD) process. The coating material has a different composition than the core particle. The difference in composition permits fine control over the refractive index of the coated particles, allowing good matching tooth enamel and to the binder materials used in the composite.

This invention relates to filler materials for dental composites and to dental composites containing such filler materials.
So-called amalgam dental fillings are being increasingly replaced with dental composites that more closely match the color and appearance of the natural tooth. These composites generally consist of an organic resin that contains a microparticle filler. Most systems incorporate a light- or UV-curable polymeric resin, such as a diglycidylmethacrylate of bisphenol A (BIS-GMA), triethyleneglycol dimethacrylate (TEGDMA) or a urethane dimethacrylate (UDMA). The filler particles are typically barium silicate glass, quartz or zirconium silicate, combined with small colloidal silica particles.
To match the appearance of the original tooth enamel and provide a natural, tooth-like appearance, the inorganic particles must be translucent and display minimal light scattering. The composite of inorganic particles and polymeric resin must have a refractive index in the range of about 1.48 to 1.60, especially ˜1.54. Both the resin and the filler particles should have very nearly the same refractive index, to minimize light scattering. Polymeric resins can be blended to achieve this refractive index. Obtaining the necessary refractive index for the filler particles is more problematic.
One approach to producing filler particles of the required refractive index is described in U.S. Pat. No. 4,503,169 to Randklev. Randklev produces microparticles containing amorphous silica microregions interspersed with polycrystalline ceramic metal oxide microregions. Silica (SiO2) is a very low cost inorganic material having a refractive index of ˜1.46. The ceramic metal oxide used in Randklev's process is preferably zirconia (ZrO2), which has a refractive index of about 2.20, because ZrO2 has the added benefit of being opaque to x-ray radiation. Microparticles having any refractive index between that of silica and that of zirconia can be produced in Randklev's process by varying the relative proportions of these components, provided that crystalline microregions having diameters of greater than about 400 microns (the shortest wavelength of visible light) are excluded. In Randklev's process, ZrO2 is mixed with SiO2 using sol-gel techniques to form the microparticle composites. One of the problems with the sol-gel process is that the starting materials must be blended carefully and then temperature processed to obtain the composite microparticles. This processing is variable and can lead to voids in the composite microparticle. These voids scatter light and increase the opacity. Large crystallites of ZrO2 that form during the thermal processing also lead to light scattering. This seriously degrades the appearance of the composite. In addition, there is very little control over the resulting refractive index of the dental composite when using these composite microparticles.
It would therefore be desired to produce a filler material for dental composites, which has a carefully controlled refractive index and exhibits a desirable opacity and minimal light scattering.


The process for forming a microporous polymeric semi-crystalline film, involving the steps of cold compressive extruding a precursor film, preferably in a biaxial fashion, so as to compress the film by a factor of about 2 to 1 to about 10 to 1, stretching the film by about 100 to about 500 percent, preferably in a biaxial fashion, and heat annealing either before, during, or preferably after the stretching step at a temperature up to the alpha transition temperature of the polymer for a time sufficient to maintain the microporous character of the final film.

1. Field of Invention
This invention relates to microporous films. More particularly, this invention relates to microporous films which are produced by a stretching and heat setting process.
2. Prior Art
The preparation of microporous films, i.e. films having a pore size in the range of about less than about 0.1 microns has been accomplished by a wide variety of methods in the prior art.
One method has involved the physical penetration of a precursor film such as by needle punching or by treatment with chemical agents or radiation.
A more common method of preparing microporous films has involved the addition of a leachable agent to a polymer melt. The film is then formed and the leachant is dissolved out of the film to leave behind a porous product. The disadvantage of this process, among others, is that it requires that polymeric films be treated with materials which diminish the properties of the final films, if they are not totally dissolved from the film. Leached microporous films are therefore often "contaminated" by the presence of the leachant.
U.S. Pat. No. 4,247,478 is typical of the prior art patents which have involved leaching of a material from a precursor film to form a microporous film. According to this patent, a thermoplastic polymer is dissolved in a compatible liquid, as defined in the patent, the solution is then allowed to assume the desired shape and is cooled under certain specified conditions. Thereafter, a portion of the compatible liquid is removed to form a microporous film.
U.S. Pat. Nos. 3,382,306; 3,558,764; and 3,679,538 disclose the preparation of a microporous film formed from a polyolefin, polyacetal, polyethylene sulfide, etc. Basically the process in forming these films involves the steps of melt extrusion under high stress, annealing, cold drawing, hot drawing and then heat setting. According to the process of these patents, melt extrusion under high stress serves to form a row nucleated precursor film the superstructure of which is further perfected by annealing. The resulting film is then drawn and heat set. While the products produced from these films have excellent properties, the resulting films are much larger in pore size than the films of the instant invention. Moreover, the "pores" of the films described in the above patents are more like slits than they are like true pores. Also, the process of these patents does not permit the manufacture of films having extremely large thicknesses because it is difficult to produce completely row nucleated products with thicker films. Finally, the films prepared according to these patents are extremely weak in the transverse direction.
U.S. Pat. No. 3,250,146 appears to disclose the biaxial treatment of various types of films. See also U.S. Pat. No. 2,494,334, U.S. Pat. No. 4,076,785, and U.S. Pat. No. 2,494,334. However, none of the films described in these patents are microporous in nature.
Accordingly, it is an object of this invention to prepare microporous films which are of greater thickness than those prepared in the prior art.
It is another object of this invention to prepare microporous films which are not contaminated with leachants or other materials.
It is another object of this invention to prepare microporous films which have uniform pore size distributions.
It is yet another object of this invention to prepare microporous films having pores which are generally circular in nature and which pores are extremely small in diameter.
These and other objectives are attained according to the process of the instant invention.

Microporous membrane from cold-rolled precusor film


A method and system for trading an instrument such as a financial instrument. A customer generates a request for a price and provides data concerning the instrument for which the price is sought. The price requested may be a price to buy (bid) or sell (offer) the instrument. The request is provided to a group of users via a communication network. Each user is capable of at least generating a price response to the request. The user responses are provided to the customer via the communication network. The best price response generates a first indication to the user which provides such price response. All other users which provide a price response are provided with a second indication, which is different from the first indication and which does not include the best price. At any time, the customer may accept any pending response, amend the request, or cancel the request. The users may adjust their price responses up or down, or cancel their response, at any time prior to customer acceptance, taking into account whether their response generates the first indication or second indication.

In a conventional open auction, each potential buyer of an instrument knows the bids of the other potential buyers. Such an open auction allows the potential buyers to take advantage of their knowledge of the details of the other bids and can result in the winning bidder obtaining the instrument for a lesser value than he or she would otherwise have been willing to pay. Thus, providing information regarding other potential buyers' bids to each potential buyer may be detrimental to the seller.
Alternatively, in a sealed bid auction, potential buyers do not know any details of the bids of others. Such a system also can operate to provide less than a best bid price, because potential buyers may hesitate to adjust bids since they may simply be "bidding against themselves."
Thus, there is a need to create a system for auctions which encourages bidders (or offerors) to present their best possible bids (or offers) in an efficient manner.

System and method for trading an instrument


A power supply device has a pulse width control circuit for controlling voltage converting operation of a voltage converting circuit by changing a pulse width. A momentary interruption detecting circuit detects a change in an output voltage when the output voltage suffers a momentary interruption over a short period of time. A full short-circuit detecting circuit detects a change in the output voltage when the output voltage suffers a short circuit over a very short period of time. A short-circuit control circuit stops a pulse width changing control process of the pulse width control circuit a predetermined period of time after the momentary interruption detecting circuit has detected that the output voltage suffers a momentary interruption, and stops the pulse width changing control process of the pulse width control circuit immediately when the full short-circuit detecting circuit detects that the output voltage suffers a short circuit.

The present invention relates to a power supply device for regulating and supplying a voltage generated by a DC power supply to an outer circuit. The power supply device has a capability for controlling an output voltage to prevent circuit components from being damaged upon occurrence of a momentary output voltage interruption or short circuit.
In recent years, fast-paced efforts have been made for developing small-size, lightweight, and low-power-consumption electronic devices such as magnetic recording and reproducing devices with combined cameras. For lower power consumption, a switching power supply is indispensable to such electronic devices. It is primarily customary for the switching power supply to use transistors in performing its switching operation.
Electronic devices having dry batteries such as nickel-cadmium (NiCd) cells or nickel-hydrogen (NiH) cells as a power source are generally widely used in the art. Since these dry batteries have output voltages in a relatively low range, the voltages that can be supplied from these cells may not match voltages that are used in electronic devices. Therefore, a voltage converting device called a DC/DC converter is used to convert the output voltage of a dry battery for stably supplying a necessary power supply voltage to a desired electronic circuit.
If an abrupt large current flows from a switching power supply due to a short circuit in the load connected to the output stage of the switching power supply, then the fuse of an electronic device incorporating the switching power supply may possibly melt, or transistors or other components of the electronic device may be broken. According to one approach to solving this problem, a short-circuit detecting comparator is incorporated in the IC (Integrated Circuit) of a switching power supply. When the output voltage of the switching power supply exceeds a certain preset voltage, a timer latch circuit is activated. The output voltage of the switching power supply is cut off if it remains continuously in excess of the preset voltage for a period of time set by the timer latch circuit.
Some conventional DC/DC converters have a switching element in the form of a bipolar transistor The amount of current that flows in a DC/DC converter is limited by the base current of a bipolar transistor. Consequently, it is uncommon for the fuse of an electronic circuit incorporating a DC/DC converter to melt while the timer latch is monitoring the output voltage for a period of time set thereby.
Recently available DC/DC converters employ a switching element in the form of an N-channel MOS-FET (Metal Oxide Semiconductor-Field Effect Transistor), which is selectively turned on and off depending a switching pulse applied thereto.
A conventional boosting DC/DC converter power supply device will be described below. When an input voltage is applied from a dry battery, a voltage converting circuit converts the input voltage into an output voltage Vo, which is supplied to a load circuit. A PWM (Pulse Width Modulation) control circuit generates a PWM signal for turning on and off a switching transistor of the voltage converting circuit. The output current from the switching transistor is rectified to produce the output voltage Vo.
The voltage converting circuit will be described below. In the voltage converting circuit, an FET has a drain connected to a power supply terminal through a choke coil and a source connected to ground. The FET has a gate connected to a pulse input terminal for being supplied with a switching pulse from the PWM control circuit.
The junction between the FET and the choke coil is connected to the anode of a diode (Schottky diode). A capacitor has a terminal connected to the cathode of the diode and another terminal connected to ground.
When the FET is switched off by the switching pulse, a voltage higher than the voltage at the power supply terminal is produced at the junction between the choke coil and the diode due to the excited energy discharged from the choke coil, charging the capacitor. The voltage at the junction gradually drops and reaches a level substantially equal to the ground voltage when the FET is turned on again. Therefore, a voltage change in response to the switching pulse appears at the anode of the diode. The voltage change is rectified by the diode into a voltage higher than the input voltage. The rectified voltage is smoothed by the capacitor, and the smoothed voltage is supplied from an output terminal to the load.
Japanese Patent Laid-open No. Hei 11-164548 discloses a power supply device for preventing an overcurrent from flowing through a switching element when an input AC voltage abruptly increases. According to the disclosed power supply device, when the input AC voltage is momentarily interrupted, a comparator does not generate a pulse because it is not supplied with a voltage from a rectifying circuit during the momentary interruption of the input AC voltage. At this time, a pulse detecting circuit cannot detect a pulse and outputs a breaking signal. Since the pulse detecting circuit outputs the breaking signal with a delay of about 20 msec., it continuously outputs the breaking signal for about 20 msec. even after the momentary interruption of the input AC voltage is recovered. When a drive pulse generating circuit receives the breaking signal from the pulse detecting circuit, it stops generating a drive pulse, turning off the switching element.
Japanese Patent Laid-open No. Sho 63-77375 reveals a starter circuit for a DC/DC converter, the starting circuit being capable of preventing an output voltage of the DC/DC converter from abruptly rising due to a main power supply interruption. When a voltage supplied from the main power supply to the primary side of the DC/DC converter exceeds a reference voltage, a soft starter circuit for the DC/DC converter is energized again.
The applicant of the present application has applied for a patent on a power supply device as disclosed in Japanese Patent Application No. 2003-281968. According to the disclosed power supply device, even when a voltage supplied from a dry battery is temporarily interrupted, an upper limit (MAX-Duty) for a PWM signal is forcibly lowered to prevent an excessive voltage from being applied to the load, thereby preventing a device connected to the load from being broken and also preventing a PWM control IC to which the output voltage is applied as a feedback signal from being broken.
When a short circuit occurs in the circuit employing the FET of the above DC/DC converter, since the short circuit occurs with the on resistance (several hundred milliohms) of the FET, a large current flows at the instant of the short circuit. Therefore, before the short-circuit detecting mechanism of the IC operates, the fuse may melt, or the FET may be destroyed.
The above problem arises in the event of a short circuit occurring in certain adverse user environments such as moisture condensation. Even through the problem can be solved by improving such adverse user environments, once the fuse melts, the power supply device needs to be taken care of by the manufacturer's repair services.
The power supply device disclosed in Japanese Patent Laid-open No. Hei 11-164548 turns off the switching element in the event of an input AC voltage interruption. The starter circuit disclosed in Japanese Patent Laid-open No. Sho 63-77375 detects that the input voltage applied to the primary side of the DC/DC converter exceeds a prescribed level and energizes again the soft starter circuit for the DC/DC converter.
A power supply device according to the present invention is not arranged to stop the output only when the input voltage is interrupted as disclosed in Japanese Patent Laid-open No. Hei 11-164548, but detects a short circuit in various output voltage patterns and stops a PWM signal. The power supply device according to the present invention does not energize a soft starter circuit again unlike the starter circuit disclosed in Japanese Patent Laid-open No. Sho 63-77375.


Disclosed is a hinge device for a mobile phone having a rotation type display including a body housing, a folder having a display unit, and a connection member for rotatably connecting the folder to the body housing such that the folder is rotatably moved into an open position or a closed position with respect to the body housing. The hinge device includes a hinge module having a plate shape. The hinge module is accommodated in the folder and rotatably coupled to the connection member while facing the connection member so as to rotate the folder relative to the connection member about a hinge axis thereof.

1. Field of the Invention
The present invention relates to a mobile phone having a rotation type display, and more particularly to a hinge device for a mobile phone including a plate-type hinge module for rotatably supporting a folder having a rotatable display unit.
2. Description of the Related Art
In general, a "portable communication apparatus" refers to an electronic appliance allowing users to make wireless communication with other users while carrying the portable communication apparatus. Such portable communication apparatuses are classified into various types according to their appearance. For example, the portable communication apparatuses are classified as either a bar-type portable communication apparatuses, flip-type portable communication apparatuses, or folder-type portable communication apparatuses, according to their appearance. The bar-type portable communication apparatus has a single housing shaped like a bar. The flip-type portable communication apparatus has a flip which is pivotably coupled to a bar-shaped housing by a hinge unit. The folder-type portable communication apparatus has a folder coupled to a single bar-shaped housing by a hinge unit in such a manner that the folder can be rotated in order to be folded towards or unfolded away from the housing.
Further, portable communication apparatuses may be classified into rotation-type communication apparatuses and sliding-type communication apparatuses according to ways of opening and closing the portable communication apparatuses. In the rotation-type portable communication apparatus, two housings are coupled to each other in such a manner that one housing rotates opened or closed relative to the other while they face each other. In the sliding-type portable communication apparatus, two housings are coupled to each other in such a manner that one housing can longitudinally slide along the other housing. These variously classified portable communication apparatuses can be easily understood by those skilled in the art.
Recently, designs of such portable communication apparatuses tend to be compact, slim, and light in consideration of portability. However, the conventional portable communication apparatuses are convenient only when making voice or image communication with other users.
As shown in FIGS. 1 to 3, a conventional display rotation type portable terminal includes a body housing 10 provided at one end thereof with a first hinge axis A1, a folder 20 and a connection member 30. The body housing 10 has various key buttons 11 and a microphone 12. The connection member 30 connects the body housing 10 to the folder 20 and allows the folder 20 to rotatably move into an open position or a closed position with respect to the body housing 10 about the first hinge axis A1. In addition, the connection member 30 is provided with a second hinge axis A2. The folder 20 is rotatably moved with respect to the connection member 30 about the second hinge axis A2. The folder 20 is provided with a display unit, such as an LCD 21, and a speaker 22.
A hinge module 40 is accommodated in the connection member 30 so as to allow the folder 20 to rotate about the second hinge axis A2.
According to the conventional display rotation type portable terminal, the display unit of the folder can be rotated so as to provide users with a wide screen when viewing a moving picture, a video, or playing a game.
However, in the conventional display rotation type portable terminal, the hinge module for rotating the display unit of the folder is exposed to an exterior, so the hinge module may be easily broken when external impact is applied thereto. In addition, since the hinge module has a large size and thickness, not only is it difficult to make a compact-sized portable terminal, but also various limitations may occur when designing the portable terminal.
In addition, according to the hinge module of the conventional rotatable display type portable terminal, the rotational function of the folder may deteriorateover time.

Hinge device for mobile phone having rotation type display


Conveyor safety guard modules that are configured to be inserted between adjacent rollers in motor driven roller conveyor systems and shield drive bands or belts coupled between the adjacent rollers so as to protect workers from having their work gloves, loose hair, loose clothing, etc. becoming entangled in the drive bands or belts and causing injury.

The present invention relates generally to conveyor systems and more particularly to conveyor safety guard modules for motorized roller conveyor systems which conveyor safety guard modules protect workers from being injured by the drive mechanisms of the conveyor systems.
Conveyor systems are used for a variety of purposes. Exemplary conveyor systems include packaging systems, order fulfillment systems, manufacturing systems, shipping sortation systems, and returns processing systems. Some conveyor systems use centralized multi-horsepower AC motors to drive shafts, belts or chains that, in turn, rotate banks of rollers to transport items throughout the conveyor system. Other conveyor systems include rollers with internal DC "micro-horsepower" motors that rotate a localized segment of rollers. The latter systems include brushless DC roller conveyor systems.
A brushless DC roller conveyor system includes several components and features, such as drive rollers with self-contained brushless DC motors, intelligent local controllers, and networking between the controllers based on bidirectional communication protocols.
In motorized roller conveyor systems a length of a conveyor system is made up of sections that include a single motor driven roller. As the motor driven roller is rotated, drive bands or belts coupled to the ends of adjacent rollers, including the motor driven roller, transfer rotational movement to each of the rollers in each section. FIG. 2 of U.S. Pat. No. 6,370,447 provides an example of the use of "mounting belts 10b" that transfer rotational force of a motorized roller 10 to the free rollers 10a.
The use of drive bands or belts coupled to the ends of adjacent rollers for purposes of transferring rotational movement from motor driven rollers to free rollers presents a safety hazard to personnel whose jobs require working next to such conveyor systems and placing or removing or orienting packages and other articles on the conveyor sections. Specifically, such workers' gloves, loose hair, clothing, etc. can become caught and entangled and pulled by the drive bands or belts, causing injury to the workers.
U.S. Pat. No. 10,988,314 to Guerra et al. teaches the need of a guide edge in conveyor systems that have angled roller configurations designed to move conveyed articles to one side of the conveyor system. In FIG. 4 a guard that functions as a guide edge can be bolted along one side of a conveyor.
The present invention provides conveyor safety guard modules for use with motor driven conveyor systems that can be retrofitted onto existing motor driven conveyor systems and used to protect workers from injuries from otherwise exposed drive bands or belts that transfer rotational movement from motor driven rollers to free rollers.