A motor controller architecture and method of operating the same. The motor controller includes a function for estimating the low speed operation of the motor, for example by evaluating the response to a periodic excitation signal injected into the control loop of the controller architecture. Control logic for controlling the motor at transitional speeds between low speed control and high speed (back emf) control is provided in some embodiments.

This invention is in the field of control systems for electric machines. Embodiments described in this specification are more specifically directed to control of alternating current (AC) electric motors operating at low speed.
Even more than a century after their introduction, AC electric motors continue to enjoy widespread deployment to this day, over a wide range of applications and sizes. AC motors have become especially popular due to their reliability and relatively low cost. Recently, modern high-speed and low-cost programmable microcontrollers have enabled complex motor control algorithms that can now control AC motors to attain increased efficiency in complex commercial, industrial, and consumer equipment and processes. For example, these control algorithms provide the ability to operate AC motors at variable speeds, which in some applications allows for the elimination of complex gears and transmissions in the driven mechanical system. These new control algorithms can also enhance the performance/cost ratio of the motor system, and increase load efficiencies, and maximize the torque per ampere performance of the motor, thus saving significant power.
Field-oriented control ("FOC") has become a common technique in modern motor control systems. According to this approach, the stator windings of the AC motor are driven, for example by pulse-width-modulation, in such a way as to maximize the torque/ampere performance of the motor. For the case of permanent magnet rotors, FOC seeks to drive the field flux vector angle so that the rotor flux angle is 90° out of phase from the field flux, which is at the maximum torque condition.
Field-oriented control of AC motors is complicated because the rotation of the magnetic field in the stator with respect to the rotating magnetic field of the rotor can be asynchronous. As such, AC induction motor operation is characterized by a set of differential equations with time varying coefficients. The well-known "Park" transform, on which many AC motor control algorithms are based, transforms those differential equations into a set of differential equations that have time invariant coefficients. In particular, the Park transform considers motor operation according to a two-dimensional (d, q) coordinate system, where axis d is aligned with the field flux linkage component and orthogonal axis q is aligned with the torque component. By separating the field flux linkage and torque components, the motor torque can be controlled without affecting the field flux, allowing for dynamic torque control, proportional-and-integral (PI) control algorithms, and the like. Typical FOC control loops for AC motors also utilize the well-known Clarke transform to transform the three-phase time variant system of differential equations into a two coordinate time variant system, which the Park transform converts into the (d, q) coordinate system.
As fundamental in the art, closed loop control of AC motors requires knowledge of the current state of the motor, typically including the position and velocity of the rotor. Mechanical transducers, such as encoders and the like, have been used for years to sense the position and velocity of the rotor shaft in conventional electric motors. However, as is well known in the art, these sensors and associated wiring and connectors add significant cost and complexity in the motor and its control system, and are prone to inaccuracy and mechanical failure. To address these concerns, sensorless motor control techniques have been developed in the art. Sensorless induction motor control is commonly implemented by estimating the back electromagnetic force induced in the stator windings by the rotation of the rotor, from which the rotor position and velocity can be determined.
FIG. 1 illustrates a conventional controller architecture for controlling the operation of an AC motor. As well-known in the art and as discussed above, feedback control loops based on the Park transform operate according to reference signals in the direct (d) and quadrature (q) phases, shown in the example of FIG. 1 by reference currents Idref and Iqref, respectively. In the direct phase leg of the loop, error generator 2d receives direct phase reference current Idref and a feedback current Id, and forwards error signal εd corresponding to the difference of those two currents to proportional-integral (PI) controller 4d. PI controller 4d applies error signal εd to a conventional control function, which in this case is based on a sum of proportional and integral terms involving error signal εd; other control functions may alternatively be used, including PID (proportional-integral-differential) functions and the like. PI controller 4d produces direct phase control signal Vd, which is input to inverse Park transform function 6. The quadrature phase leg of this conventional control loop is similarly arranged, with error generator 2q receiving quadrature phase reference current Iqref and feedback current Iq, and forwarding error (i.e., difference) signal εq to proportional-integral (PI) controller 4q, which in turn applies a conventional control function (e.g., proportional-integral) to produce quadrature phase control signal Vq for input to inverse Park transform function 6. As conventional in the art, inverse Park transform function 6 produces spatially fixed α and β phase control signals Vα, Vβ by transforming the d and q phase control signals. Control signals Vα, Vβ are in turn applied to conventional space vector/pulse-width modulation (PWM) function 8, which produces three-phase PWM drive signals PWM(a, b, c) at the desired duty cycles and phase timing for motor phases a, b, c, respectively. Three-phase inverter 10 is a conventional power function that drives three stator windings of motor M using DC voltage Vdc, according to PWM drive signals PWM(a, b, c).
The feedback loop in this conventional architecture is based on currents in each of the stator windings, as sensed by conventional current sensors 11 and communicated as current signals Ia, Ib, Ic for the three motor phases. As shown in FIG. 1, current sensors 11 operate to estimate the back emf induced in the stator windings by the rotation of the rotor of motor M; this sensed back emf can be used to determine the position and velocity of the rotor during operation of motor M. These sensed currents Ia, Ib, Ic are typically sampled and digitized, and communicated to Clarke transform function 12 for conversion into spatially fixed α and β phase feedback signals Iα, Ib, which are applied to Park transform function 14 to produce d and q phase feedback signals Id, Iq, respectively. These feedback signals Id, Iq are applied to error generators 2d, 2q, respectively, as discussed above, closing the control loop. Accordingly, the architecture of FIG. 1 controls the operation of motor M according to the input reference currents Idref and Iqref.
Accurate estimation of rotor position and velocity requires a back emf signal of adequate magnitude and fidelity. Because back emf is proportional to rotor speed, the motor must be operating at a sufficient speed to produce a back emf having an acceptable signal-to-noise ratio. As such, conventional sensorless motor control is not well-suited for low speed control of AC motors. However, certain new AC motor applications require low speed control. For example, washing machine motors must drive an agitation cycle in which the motor operates at low RPM and reverses direction, under heavy load. Variable-speed motor control of this low-speed agitation cycle, and similar cycles, can eliminate the complex gearing and transmission that is otherwise required in modern washing machines. So-called "e-bikes", which are bicycles that include integrated motors to assist in propulsion, provide another application in which low-speed closed loop motor control is desirable, considering that e-bike motors necessarily drive loads at relatively low speeds over significant portions of their operating time.
By way of further background, sensorless initial position detection ("IPD") techniques are known in the art. One class of these technique uses the inherent saliency (i.e., the extent to which induction is dependent on rotor position) of the electric motor to produce a signal from which rotor position may be deduced. These conventional IPD techniques inject a high frequency carrier signal into the stator reference voltage signal. The response of the stator windings to these high frequency components, as reflected in stator feedback current, is then evaluated by a processor in the motor control system to determine the position of the rotor.
By way of further background, Kim et al., "Using Low Resolution Position Sensors in Bumpless Position/Speed Estimation Methods for Low Cost PMSM Drives", Industry Applications Conference (IEEE, 2005), pp. 2518-24, describes a motor control architecture in which a low resolution Hall sensor arrangement measures rotor behavior at low speed acceleration, and back emf measures rotor behavior at high speed operation. The Kim et al. article also describes operating a motor according to a "crossover" function, namely a frequency-dependent weighted sum of the Hall sensor and back emf measurements, that produces estimates of rotor position and speed at intermediate frequencies between the low speed and high speed operating regimes.

Angle/frequency selector in an electric motor controller architecture


A semiconductor memory device including: a memory cell array including a plurality of word lines, a plurality of bit lines, and memory cells arranged in portions where the plurality of word lines and the plurality of bit lines intersect with each other; a plurality of data bus lines connected to the plurality of bit lines; a plurality of sense amplifiers individually connected to the plurality of data bus lines and configured for detecting memory data stored in corresponding memory cells based on values of currents that are generated in the individual data bus lines in accordance with the memory data.

1. Field
The embodiments relate to semiconductor memory devices capable of detecting whether a short circuit has occurred between data bus lines.
2. Description of the Related Art
In a semiconductor memory device, a memory cell array and external input/output terminals or other internal logical circuits are connected to each other with a plurality of data bus lines therebetween. The memory cell array includes a plurality of word lines, a plurality of bit lines, and memory cells arranged in portions where the plurality of word lines and the plurality of bit lines intersect with each other. In accordance with the layout of components constituting a chip, that is, in the case where the wire lengths of the data bus lines are increased a short circuit failure caused by a manufacturing process may occur between adjacent data bus lines.
By writing a specific data pattern into memory cells and reading the specific data pattern in a performance test process, such a short circuit failure between data bus lines can be detected. The data pattern to be written is selected in such a manner that data items having different levels (that is, a data item at level HI and a data item at level L or a data item at level L and a data item at level H) are output to adjacent data bus lines.
However, in the case of carrying out the above-mentioned performance test, a process for writing data must be performed. In addition, after the performance test is carried out, a process for deleting data must be performed. In particular, since a memory device, such as a flash memory device, including an electrically erasable programmable read-only memory (EEPROM) serving as a memory cell, which requires a relatively long time to perform the writing process and the deleting process, the throughput of the performance test is reduced.
In order to solve the above-described problem, technology described in Japanese Patent Laid-Open No. 7-192500 is available. According to the technology, a test circuit for floating a word line or the like for which a short-circuit check is to be performed and for applying a reference voltage is provided.
In addition, technology described in Japanese Patent Laid-Open No. 2000-195300 is available. According to the technology, mask read-only memories (ROMs) are added to bit lines within a memory cell array and a data pattern of data items for short circuit testing is written to the mask ROMs. Thus, by selecting mask ROM memory cells and outputting a data pattern of data items for testing bit lines in a short circuit failure detection test process, a detection whether a short circuit failure has occurred between the data bus lines can be performed by outputting different data items to adjacent data bus lines and determining whether the data outputs are the same as the expected values.


This invention provides an easy-to-manufacture, easy-to-analyze calibration object which combines measurable and repeatable, but not necessarily accurate, 3D features—such as a two-sided calibration object/target in (e.g.) the form of a frustum, with a pair of accurate and measurable features, more particularly parallel faces separated by a precise specified thickness, so as to provide for simple field calibration of opposite-facing DS sensors. Illustratively, a composite calibration object can be constructed, which includes the two-sided frustum that has been sandblasted and anodized (to provide measurable, repeatable features), with a flange whose above/below parallel surfaces have been ground to a precise specified thickness. The 3D corner positions of the two-sided frustum are used to calibrate the two sensors in X and Y, but cannot establish absolute Z without accurate information about the thickness of the two-sided frustum; the flange provides the absolute Z information.

In manufacturing and assembly processes, it is often desirable to analyze an object surface to determine the nature of features and/or irregularities. The displacement (or "profile") of the object surface can be determined using a machine vision system (also termed herein "vision system") in the form of a laser displacement sensor (also termed a laser beam "profiler"). A laser displacement sensor captures and determines the (three dimensional) profile of a scanned object surface using a planar curtain or "fan" of a laser beam at a particular plane transverse to the beam propagation path. In a conventional arrangement, a vision system camera assembly is oriented to view the plane of the beam from outside the plane. This arrangement captures the profile of the projected line (e.g. extending along the physical x-axis) on the object surface, which, due to the baseline (i.e. the relative spacing along the y-axis) between the beam (sometimes characterized as a "fan") plane and the camera causes the imaged line to appear as varying in the image y axis direction as a function of the physical z-axis height of the imaged point (along the image x axis). This deviation represents the profile of the surface. Laser displacement sensors are useful in a wide range of inspection and manufacturing operations where the user desires to measure and characterize surface details of a scanned object via triangulation. One form of laser displacement sensor uses a vision system camera having a lens assembly and image sensor (or "imager") that can be based upon a CCD or CMOS design. The imager defines a predetermined field of grayscale or color-sensing pixels on an image plane that receives focused light from an imaged scene through a lens.
In a typical arrangement, the displacement sensor(s) and/or object are in relative motion (usually in the physical y-coordinate direction) so that the object surface is scanned by the sensor(s), and a sequence of images are acquired of the laser line at desired spatial intervals-typically in association with an encoder or other motion measurement device (or, alternatively, at time based intervals). Each of these single profile lines is typically derived from a single acquired image. These lines collectively describe the surface of the imaged object and surrounding imaged scene and define a "range image" or "depth image".
Other camera assemblies, know to those of skill, can also be employed to capture a 3D image (range image) of an object in a scene, such as stereoscopic cameras, time-of-flight cameras, LIDAR-based cameras, etc. The term range image is used to characterize an image (a two-dimensional array of values) with pel values characterizing Z height at each location, or characterizing that no height is available at that location. The term range image is alternatively used to refer to generic 3D data, such as 3D point cloud data, or 3D mesh data. The term range and gray image is used to characterize an image with pel values characterizing both Z height and associated gray level at each location, or characterizing that no height is available at that location, or alternatively a range and gray image can be characterized by two corresponding images-one image characterizing Z height at each location, or characterizing that no Z height is available at that location, and one image characterizing associated gray level at each location, or characterizing that no gray level is available at that location. The term range image is alternatively used to refer to range and gray image, or 3D point cloud data and associated gray level data, or 3D mesh data and associated gray level data. For example, structured light systems, stereo vision systems, DLP metrology, and other arrangements can be employed. These systems all generate an image that provides a height value (e.g. z-coordinate) to pixels.
A 3D range image generated by various types of camera assemblies (or combinations thereof) can be used to locate and determine the presence and/or characteristics of particular features on the object surface. In certain vision system implementations, such as the inspection of circuit boards, a plurality of displacement sensors (e.g. laser profilers) are mounted together to extend the overall field of view (FOV) (wherein the term "field of view" refers to measurement range) of the vision system so as to fully image a desired area of the object (e.g. its full width) with sufficient resolution. In the example of a laser profiler, the object moves in relative motion with respect to the camera(s) so as to provide a scanning function that allows construction of a range (or, more generally a "3D") image from a sequence of slices acquired at various motion positions. This is often implemented using a conveyor, motion stage, robot end effector or other motion conveyance. This motion can be the basis of a common (motion) coordinate space with the y-axis defined along the direction of "scan" motion.
It is recognized that profilers (also termed "profile sensors") can provide fast, accurate, non-contact 3D measurements by moving a scene with respect to a calibrated image formation system consisting of a light-sheet and a camera. The vast majority of profile sensor implementations model the structured light (e.g. laser) sheet projected therefrom as a plane (even though real physical systems are imperfect). Because of these imperfections—for example the profiler may actually project an arcuate or curved sheet—modeling the sheet more accurately than a simple plane improves the sensors' 3D measurement accuracy. Furthermore, accurately scanning scenes requires accurately knowing the relative motion between the scene and the image formation system. Better accounting for these variables can improve scanning accuracy.

System and method for calibrating a plurality of 3D sensors with respect to a motion conveyance


A method for isolating a horizontal tie-in pipeline of an inactive hydrocarbon-producing well from a main pipeline to prevent flow of hydrocarbons into the tie-in pipeline includes the steps of: identifying a location of a junction of the tie-in pipeline and the main pipeline and cleaning the tie-in pipeline by deploying a locating and cleaning assembly into the tie-in pipeline, withdrawing the locating and cleaning assembly, deploying a plug device having a longitudinally extending forward probe and a sealing element to the location of the junction, and remotely actuating the sealing element. The locating and cleaning device includes a pipeline junction sensing element longitudinally extending from a forward end of the locating and cleaning device. The sensing element is connected to a valve which, when open, relieves pressure in the locating and cleaning assembly as an indicator of the location of the junction.

Oil and gas wells which are actively producing hydrocarbon products are typically provided with branch pipelines which join another pipeline. Similarly, disposal lines for water and acid gas may also be connected in a similar fashion. Such branch pipelines are known in the art as "tie-ins." Tie-ins usually extend underground from a producing well to a connection point where the hydrocarbons produce by the producing well join the operating pipeline, which may be a larger pipeline. The joint of the tie-in may be provided as a "T" (when the tie-in joins at a right angle) or a "Y" (when the tie-in joins at an angle other than a right angle).
One aspect of maintenance of hydrocarbon producing wells includes tasks which relate to a status known as "well suspension." Well suspensions have typically involved temporarily halting production for the purposes of performing workover tasks, after which the producing well is brought back on line. Well suspensions for extended periods of time usually are economically influenced by a critical well failure or uneconomic production. Lower resource prices have incentivized owners to consider temporarily halting production for a significant period with the intention of re-starting production when resource prices increase. One aspect of well suspension includes shutdown and of the corresponding pipeline. Regulations relating to proper suspension of the pipeline and corresponding tie-in exists in various jurisdictions.
A number of technologies for temporarily halting the flow of hydrocarbons or other fluids in wellbores, pipelines and other conduits have been described.
U.S. Pat. No. 8,091,633, incorporated herein by reference in its entirety, describes a tool used for treating and/or maintaining a wellbore that includes acoustic transducers for locating a lateral wellbore that intersects a primary wellbore. The tool includes a sensor to sense water and/or gas, and if the water and/or gas enters the primary wellbore from a lateral wellbore, the lateral to primary intersection can be identified by correlating information from the sensor and acoustic transducers. If needed, the tool can be used to plug the water and/or gas supplying lateral wellbore. The tool may include a bendable sub portion for orienting a portion of the tool for insertion into the lateral wellbore and a plug section for plugging the lateral wellbore after insertion therein.
U.S. Pat. No. 4,484,602, incorporated herein by reference in its entirety, describes a method and apparatus for detecting and sealing leaks in a sewer branch pipe including a packer member which travels along the main sewer pipe by remote control. When the packer is correctly located, the main pipe region surrounding the branch entrance is sealed off. The packer is rotated until a slot in the packer is orientated to the branch. An inflatable tube in the packer is then inflated, causing the tube to elongate and enter the branch. The remote end of the tube forms a seal against the inside of the branch so that the area of the branch near the junction with the main pipe is included in the sealed off area. Fluid can be pumped into the sealed off space to detect if a leak is present; in which case a sealant fluid is pumped into the space. Afterwards, the tube can be deflated and retracted and the traveller repositioned at the next branch. The disclosure includes a method of detecting and sealing leaks, in which an inflatable tube is used to provide a means to enter the branch, and to seal the branch away from its junction with the main pipe.
U.S. Pat. No. 4,869,324, incorporated herein by reference in its entirety, describes modifications for both single unit and dual unit inflatable packers or bridge plugs permitting such inflatable tools to be inserted in a well through the primary tubing string which in turn is suitably sealably anchored in the well above the producing formations. The inflatable tool is inserted into the well on a conduit, such as coiled tubing, and fluid pressure transmitted through the conduit is utilized to effect the expansion and setting of the inflatable elements of the inflatable tool. The conduit is connected to the inflatable tool by a fluid pressure operated release mechanism and, following the inflation of the inflatable element or elements, the conduit may be utilized to supply treatment fluid or cementing fluid to a formation isolated by the inflatable tool. Alternatively, the conduit may be disconnected from the inflatable tool and retrieved from the well to permit the inflated tool to maintain a production formation in an isolated condition, to prevent further leakage of a leaking packer, or to permit wireline installation of a choke to regulate the amount of flow into or out of a producing or injection formation isolated by the inflated tool. Applications of the packers and bridge plugs are focused on deployment in production or injection tubing.
US Published Patent Application No. 2011/0036564, incorporated herein by reference in its entirety, describes a bridge plug that can be deployed downhole and retrieved using a retrieval tool disposed on jointed or coiled tubing or on another bridge plug. Internally, the bridge plug has a sleeve that is movable on a stem of the plug's tailpiece. When in a first position, the sleeve prevents fluid communication through ports in the stem so that circulated fluid from the retrieval tool can be used to clear debris from the plug during retrieval. When the retrieval tool engages the sleeve in the plug, pulling up on the tool moves the sleeve to an intermediate position in which fluid pressure is equalized across the plug. Further pulling up on the tool locks the sleeve in a further position on the stem so that circulated fluid from the retrieval tool will pass directly to the stem's ports. Movement of the sleeve by the retrieval tool also releases the engaged slips and packing element on the bridge plug's mandrel. Operations envisioned for the bridge plug include: acidizing, fracturing, cementing, casing pressure tests, wellhead replacement, and zonal isolation.
U.S. Pat. No. 9,435,172, incorporated herein by reference in its entirety, describes a downhole tool conveyed via tubing within a wellbore at a wellsite. The hydraulic tool is driven by fluid pumped to the hydraulic tool via the tubing. The downhole tool further comprises a valve in fluid communication between the tubing and the hydraulic tool. The valve is configurable in the wellbore between an expanded position, establishing a bypass diverting at least a portion of the pumped fluid away from the hydraulic tool, and a compressed position, closing the bypass.
U.S. Pat. No. 6,338,390, incorporated herein by reference in its entirety, describes an apparatus and methods for drilling subterranean formations with a rotary-type drill bit. Oscillation is produced in the drill string, drill bit or cutting element, in an axial and/or torsional direction, to produce formation chips that have both thin portions and thick portions. More specifically, the oscillations cause a cutting element of the drill bit to engage the formation to various degrees, resulting in a chip that has varying thicknesses which facilitate fracture of the chip along its thinner portions, thereby reducing the likelihood of adherence of the formation chips to the drill bit or cutting element.
U.S. Pat. No. 1,875,414, incorporated herein by reference in its entirety, describes a washing and cementing device for well casings. The device is fitted to the lower end of a well casing and has a stem which triggers a valve upon contact with an obstruction in the wellbore.
Canadian Patent 2,170,711, incorporated herein by reference in its entirety, describes a locator and setting tool which is capable of locating and setting a barrier member within a cased wellbore. The tool has a casing collar locator and a packer setting assembly. The casing collar locator includes a detector to identify the locations of the casing collars and provides a signal to identify the locations. The setting tool has a motor and an associated linear drive section to operate the packer assembly.
PCT Publication No. WO 2012/177909, incorporated herein by reference in its entirety, describes a device which includes a first locating system configured to generate to sense an electromagnetic field emanating from a sonde associated with a drill head, and a second locating system including a global positioning system. The locator device includes a display on the locating system configured to display a map of the area in which the locator device resides based on a location detected by the global positioning system. The locator device also includes control electronics configured to, upon receipt of an input from a user, record location data in a memory associated with the locator device for use by a horizontal directional drilling control system.
There continues to be a need for development of processes and devices for installing a retrievable pipeline bridge plug which are suitable for deployment during well suspension operations.

Process for isolating a horizontal tie-in pipeline of an inactive hydrocarbon-producing well from a main pipeline


A position control device has a piezoelectric actuator, a power supply for applying voltage to the piezoelectric actuator, a position control unit, and a reverse low voltage control unit. The position control unit identifies a position control state in which position control is performed by displacing the piezoelectric actuator and a standby state that does not require the position control, and controls the position. When the position control unit identifies the standby state, the reverse low voltage control unit sets a reverse low voltage that is directed opposite to the polarization direction of the piezoelectric film and is lower than a coercive voltage and a set time during which the reverse low voltage is applied, and transmits a power supply control signal for generating the set reverse low voltage and set time to the power supply. Thus, a large displacement amount is achieved and a long lifetime can be realized.

1. Field of the Invention
The present invention relates to a control method for controlling displacement of a piezoelectric actuator, and more specifically to a control method capable of performing large displacements for a long time, and a position control device and disk device using this control method.
2. Background Art
When a piezoelectric element is used as an actuator, conventionally, a piezoelectric film can be electrochemically deformed by an applied voltage, its characteristic degrades, and further its function as a piezoelectric actuator can be damaged. This degradation is apt to occur especially when the voltage applied for increasing the displacement amount is increased. For suppressing the degradation, various control methods are proposed as the driving method of the piezoelectric actuator.
As the control method of the piezoelectric actuator, Japanese Patent Unexamined Publication No. 2002-288954 discloses a method of restricting the control voltage applied to the piezoelectric actuator to a threshold or below.
FIG. 7 is a block diagram illustrating the disclosed control method. Piezoelectric actuator 202 is connected to power supply 206 for driving the actuator, ammeter 204, and position control unit 208. Position control unit 208 controls the voltage of power supply 206 to provide a displacement amount set in piezoelectric actuator 202. Information on the current value measured by ammeter 204 is transmitted to position control unit 208. When the control voltage that is not lower than the threshold is applied to piezoelectric actuator 202, insulation resistance of the piezoelectric film forming piezoelectric actuator 202 further degrades.
In the control method discussed above, for suppressing such degradation of the insulation resistance, the applied control voltage is restricted to the threshold or below. When the control voltage exceeds the threshold, the time period of exceeding the threshold is restricted. The threshold is set as follows:                the threshold is set dependently on the material of the piezoelectric film; or        the characteristic between control voltage applied to the piezoelectric actuator and the current is measured, and the control voltage at which the current increases exponentially is set as the threshold.
Japanese Patent Unexamined Publication No. 2003-141832 discloses a method in which a means for detecting the insulation resistance of the piezoelectric actuator during use is disposed, and, when the means detects the decrease in insulation resistance, the insulation resistance is recovered by applying high voltage.
FIG. 8 is a block diagram illustrating this control method. Piezoelectric actuator 210 has a three-layer structure where electrode films are formed on opposite sides of the piezoelectric film. Regarding the decrease in insulation resistance of piezoelectric actuator 210, generally, the resistance of the piezoelectric film does not wholly decrease, but part of the piezoelectric film often degrades locally. In such a case, high voltage is applied to the gap between the electrode films to make high current flow intensively to a part where the electric resistance is decreased by local degradation, and thus a breakdown phenomenon such as occurrence of peeling in the electrode film around the degraded part is caused. The breakdown phenomenon is used to remove the current path from a local low resistance region to recover the insulation resistance between the electrode films.
Specifically, as shown in FIG. 8, when a predetermined voltage is applied to piezoelectric actuator 210 from position control power supply 216, current flowing through piezoelectric actuator 210 is measured by ammeter 212, and current value information is fed into degradation determining unit 218. Degradation determining unit 218, based on the current value information, compares the fed current value with a preset current allowance. When this comparison indicates that the fed current value is higher than the allowance, a switch signal is fed into signal switching unit 220. By switching in signal switching unit 220, a set voltage is applied to piezoelectric actuator 210 from high voltage power supply 214. Thus, the current path can be removed from the local low resistance region as discussed above.
Another control method of a piezoelectric actuator is also shown in "IEEE (Institute of Electrical and Electronics Engineers) transactions on magnetics, vol. 35, No. 2 (1999) p. 984". In this method, the voltage applied to the piezoelectric film is not set in a range of −X(V) to +X(V) (X is an arbitrary positive value) (typical voltage applying method), but is set in a range of 0 to X(V). In other words, the voltage range is restricted so that the voltage in the range 0 to −X(V) is not applied. In this case, the applied voltage is restricted to one-side polarity such as 0 to +X(V), and the applying direction is set to be the same direction as the initial polarization direction. As a result, the applied voltage is not applied in the direction opposite to the initial polarization direction. Therefore, the applied voltage does not cause inversion of the polarization, and the initial polarization is kept stable. When the initial polarization is kept stable, the displacement amount of the piezoelectric actuator is hardly reduced.
In the first control method of the piezoelectric actuator, long-term degradation of the actuator is suppressed by setting the absolute value of the control voltage at or below a certain threshold. The threshold is therefore set at a voltage value lower than the voltage value at which the piezoelectric actuator is not degraded by a short-term application. For example, the piezoelectric actuator is driven using, as the threshold, half the voltage value at which the degradation is not caused in a short time. The piezoelectric element hardly degrades, so that the lifetime is improved. The displaceable amount of the piezoelectric actuator is also restricted by the threshold voltage. Therefore, only a small displacement amount can be generated. In this conventional method, the displacement amount of the piezoelectric actuator and the lifetime are contradictory.
In the second control method of the piezoelectric actuator, the local breakdown phenomenon of the electrode film is used, so that the same desirable result cannot always be obtained. In other words, when high voltage is applied, the breakdown range of the degrading electrode film cannot be constant, namely the breakdown range can vary to be large or small. When a large area of the electrode film is broken, the area of the piezoelectric film to which the voltage is applied decreases greatly. Thus, the displacement amount of the piezoelectric actuator can greatly decrease, which is contrary to the objective of the method. The application of the high voltage can cause the piezoelectric element to dielectrically break down. When the application of the high voltage causes the electrode film to break down, dust is often generated. When the piezoelectric actuator is used for position control of the head slider of a hard disk device, for example, this generation of the dust can cause a failure of the entire hard disk device.
In the third control method of the piezoelectric actuator, the control voltage is applied completely in one direction, so that the movement of ions caused in the piezoelectric film by the control voltage is deflected in one direction. Accumulation of movement of ions disadvantageously causes the reduction of the insulation resistance.
The present invention addresses the conventional problems. The present invention provides a control method for controlling a piezoelectric actuator that can provide a large displacement amount and improve the lifetime of the piezoelectric actuator, and a position control device and disk device using the control method.

Control method of piezoelectric actuator, position control equipment, and disk device


The present invention relates to a device for deflecting a laser beam, comprising at least a single sided mirror (1) and means for orientating said mirror, wherein said single sided mirror is attached on one end of said axis (3) such that it can rotate about said axis and, that the means for orientating said mirror comprise means (6) for providing a magnetic field and means for providing a charged particle having a velocity v, whereby the orientation of said mirror is controlled by the resulting Lorentz force. The invention further relates to a method for deflecting a laser beam with the use of a mirror supported by an axis such that it can rotate about said axis and to a laser beam deflecting apparatus.

Lasers are currently used in numerous applications in which it is necessary to control the laser beam. A laser head in which the beam is deflected by reflection from two mirrors controlled by two galvanometers is commonly used for marking supports such as plastic or metals. Galvanometers are known means for controlling the rotation angle of the mirrors, wherein (electro)magnets within the galvanometers are brought in rotational movements. Each mirror is made to rotate in a controlled way about its own axis by the corresponding galvanometer, and the two axes are in general orthogonal positioned with respect to each other. In this way, the outgoing beam can be deflected according to a system of coordinates and its path can be controlled to obtain the required working. The present invention is related to similar devices in which two separate mirrors are able to deflect a laser beam in order to obtain all possible positions within an X-Y coordinate plane. The invention is in particular related to such a single device able to control the angle rotation of said mirror in a precise manner.
Another prior known method and device for the control of the angle rotational movement of these deflecting mirrors is the use of a plurality of electromagnets whereby elastic forces balance the magnetic forces acting upon a mirror.
In the present text 'angle rotation' means any rotational movement over an angular reach, which angular reach may be positive or negative and being in general smaller than 180°.
Other applications of these devices are for example in the medical field whereby for various treatments use is made of a laser beam controlled by means of a pair of galvanometers to execute a scanning movement.
The currently known deflection systems controlled by corresponding galvanometers are complicated, cumbersome and inaccurate. Furthermore their reaction time is long and becomes unacceptable. Another problem is the high impedance of the existing angle rotation devices, due to the high number of current wires within the electromagnets, which are needed to provide a reasonable strong magnetic field.
The purpose of the present invention is to provide an alternative for the commonly used galvanometers, such that the present invention provides a laser beam deflection device which is more compact and accurate and easy to fabricate and which permits a more precise and a more rapid manipulation of the laser beam. Another object is to provide an angle rotating device having a low impedance and as a result thereof provides for a more accurate and faster reaction time for the rotational movement.

Device and a method for deflecting a laser beam


An method employing atomic layer deposition (ALD) and rapid vapor deposition (RVD) techniques conformally deposits a dielectric material on small features of a substrate surface. The resulting dielectric film applies a phosphate-doped silicate film using atomic layer deposition (ALD) and rapid surface catalyzed vapor deposition (RVD). The method includes the following four principal operations: exposing a substrate surface to an aluminum-containing precursor gas to form a substantially saturated layer of aluminum-containing precursor on the substrate surface; exposing the substrate surface to a phosphate-containing precursor gas to form aluminum phosphate on the substrate surface; exposing the substrate surface to an aluminum-containing precursor gas to form a second substantially saturated layer of aluminum-containing precursor on the substrate surface; and exposing the substrate surface to a silicon-containing precursor gas to form the dielectric film. Generally an inert gas purge is employed between the introduction of reactant gases to remove byproducts and unused reactants. These operations can be repeated to deposit multiple layers of dielectric material until a desired dielectric thickness is achieved.

Conformal, uniform dielectric films have many applications in semiconductor manufacturing. In the fabrication of sub-micron integrated circuits (ICs) several layers of dielectric film are deposited. Two such layers are premetal dielectric (PMD) and interlayer dielectric (ILD). Both of these layers require silicon dioxide films that fill features of various sizes and have uniform film thicknesses across the wafer.
Chemical vapor deposition (CVD) has traditionally been the method of choice for depositing conformal silicon dioxide films. However, as design rules continue to shrink, the aspect ratios (depth to width) of features increase, and traditional CVD techniques can no longer provide adequately conformal films in these high aspect ratio features.
An alternative to CVD is atomic layer deposition (ALD). ALD methods involve self-limiting adsorption of reactant gases and can provide thin, conformal dielectric films within high aspect ratio features. An ALD-based dielectric deposition technique typically involves adsorbing a metal containing precursor onto the substrate surface, then, in a second procedure, introducing a silicon oxide precursor gas. The silicon oxide precursor gas reacts with the adsorbed metal precursor to form a thin film of metal-doped silicon oxide. One drawback, however, to ALD is that the deposition rates are very low. Films produced by ALD are also very thin (i.e., about one monolayer); therefore, numerous ALD cycles must be repeated to adequately fill a gap feature. These processes are unacceptably slow in some applications in the manufacturing environment.
A related technique, referred to as rapid vapor deposition (RVD) processing, is another alternative. RVD is similar to ALD in that reactant gases are introduced alternately over the substrate surface, but in RVD the silicon oxide film can grow more thickly. Thus, RVD methods allow for rapid film growth similar to using CVD methods but with the film conformality of ALD methods.
In the previously mentioned dielectric film applications, it is often desirable dope the silicate film with phosphorous, which acts as a sodium-gettering species. However, there is no known previously described process for RVD of phosphorous doped silica films.
What is therefore needed are methods for producing phosphorous-doped silica films using RVD.

Aluminum phosphate incorporation in silica thin films produced by rapid surface catalyzed vapor deposition (RVD)


A power transmission device includes a motor including a rotor having a first axial side, a second axial side opposite the first axial side, a permanent magnet embedded therein and a stator, and configured to generate a rotational force. A reducer is configured to transmit the rotational force of the motor. A wet brake mechanism is provided on the first axial side of the rotor and is configured to brake the rotation of the motor. Spaces accommodating the motor, the reducer, and the wet brake mechanism communicate with each other so that lubricant oil can flow through the spaces. A leakage magnetic flux at a second axial end face on the second axial side of the rotor is greater than a leakage magnetic flux at a first axial end face on the first axial side of the rotor having the wet brake mechanism.

1. Field of the Invention
The present invention relates to a power transmission device.
2. Description of the Related Art
Oil bath motors are structured such that a motor and a reducer are encapsulated in spaces communicating with each other and lubricant oil is circulated in the spaces. In an oil bath motor such as this, metal powder created as a result of sliding motion between components may be circulated along with the lubricant oil and supplied to the slide portions with the result that the slide portions may be unusually abraded.
One prior art discloses a compressor comprising: a power device composed of a stator and a rotor having a permanent magnet embedded therein; an airtight container for storing lubricant oil; and an oil feeding mechanism for pumping the lubricant oil stored in the airtight container so as to circulate the lubricant, wherein a through hole in which the lubricant flows is formed by drilling the rotor so as to be integrated with an air gap portion in which the permanent magnet is embedded. This allows iron powder mixed with the lubricant oil and circulated to be captured by the permanent magnet.


An idler or tensioning assembly for an electronically controlled sanding/polishing machine is provided, the sanding/polishing machine utilizing a plurality of exchangeable polishing wheel assemblies of which the idler assembly is one. Each polishing wheel assembly interfaces with the sanding/polishing machine through a coolant manifold and a polishing wheel shaft receptor. The idler assembly is operative to provide releasable tension to a sanding/polishing belt that is situated around the idler and the associated sanding/polishing wheel. The idler assembly has a pivoting idler that is actuated by a hydraulic cylinder. The hydraulic cylinder utilizes coolant tapped from the coolant manifold of the idler assembly for actuation. Coolant is provided to the hydraulic cylinder in response to a valve signal. The idler assembly thus has a tensioned mode and an untensioned mode.

1. Field of the Invention
The present invention relates to processing devices for the manufacture of prosthetic components and, more particularly, to a tensioning apparatus for a processing assembly of a processing device for the manufacture of prosthetic components.
2. Background Information
In the manufacture of prosthetic components there are various stages where components thereof need to be sanded, polished, finished or likewise operated upon (i.e. processed). Such operations are accomplished by and/or through processing devices. In most cases, these devices are now computer or electrically controlled and thus are generally automatic in the processing of prosthetic components.
One type of processing device utilizes a wheel and an associated assembly. The wheel is utilized to sand, polish, finish and/or likewise process a prosthetic component. Particularly, the processing device includes a plurality of wheels and associated assemblies that are utilized for various prosthetic component processing purpose. The wheels and associated assemblies are automatically interchanged for various types of processing.
One type of wheel and associated assembly includes a processing belt that extends about a processing wheel and a pulley. The belt provides the processing of the prosthetic component. Therefore, the belt needs to be periodically changed. It is time consuming to accomplish belt change. During the belt changing time, prosthetic components cannot be processed. Belt change also presents other disadvantages.
In order to save time, it would thus be advantageous to speed up the time necessary to change processing belts on a wheel and associated assembly, particularly of the type described herein for use with the processing device described above. Other advantages would become evident with such a device.
It should be appreciated that it is desired to have an assembly for a processing device of the type described above that allows for faster belt change of the assembly.
It should be further appreciated that it is desired to have an assembly for a processing device of the type described above that provides a tendency toward longer belt life of the assembly.
What is therefore needed in view of the above is an assembly for a processing device that allows for faster belt change of the assembly.
What is further needed in view of the above, is an assembly for a processing device of the type described above that provides a tendency to longer belt life.

This patent is subject to a terminal disclaimer.

Apparatus for processing a prosthetic component


A surge protector assembly which is easily, quickly and detachably installed in a main board of an electronic appliance for protection from instantaneous overvoltage is disclosed, the assembly has a surge relieving unit which absorbs instantaneous overvoltage in the event of a surge of voltage, a fuse connected to the surge relieving unit in series which cuts off power to the electronic elements in the event of an instantaneous overvoltage, a temperature indicator which varies in color in accordance with temperature of the assembly in order to allow a user to easily check whether the assembly is overheated or adversely affected by instantaneous overvoltage, and a plurality of lead terminals used for detachably attaching the assembly to the main board which enables a timely change of a damaged assembly with a new one.

1. Field of the Invention
The present invention relates, in general, to a surge protector assembly used for protecting electronic appliances in the event of a surge of voltage and, more particularly, to a surge protector assembly suitable for being easily and quickly mounted or replaced with a new one and effectively protecting electronic appliances from instantaneous overvoltage caused by, for example, the striking of a lightning bolt.
2. Description of the Prior Art
In typical electronic appliances such as industrial or home appliances, various electronic elements such as choke coils, resistors, condensers and surge protectors are mounted on a printed circuit board (PCB) through a lead wire inserting and soldering process. That is, the electronic elements are preliminarily arranged on a PCB by inserting the lead wires of each element into the wire inserting holes of the PCB prior to soldering the lead wires onto the PCB. In this case, the mounting and soldering of the electronic elements onto the PCB may be achieved manually by a worker or automatically by robotic machinery. Of course, it should be understood that each of the electronic elements may be received in a case, which is screwed to the PCB or engages with a rail provided on the PCB.
FIG. 11 is a sectional view showing a PCB with a varistor used as a surge protector. As shown in the drawing, the PCB 1 is printed with a wiring pattern (not shown) on the top side and has a plurality of lead wire insert holes. The lead wire 2a of the varistor 2 is inserted into a hole of the PCB 1 from the top side to the bottom side prior to soldering the lead wire 2a onto the bottom side of the PCB 1. In the drawing, the reference numeral 3 denotes a solder part formed on the bottom side of the PCB 1. Typically, various electronic elements are mounted onto the top side of the PCB 1 through a soldering process. In the operation of the PCB, one or more electronic elements on the PCB 1 may be adversely affected by overvoltage, overheating or electric shock and often requires replacement of the PCB 1 or replacement of the affected element with a new one. However, in order to replace an affected element with a new one, the affected element has to be removed from the PCB with the solder parts 3 being thermally melted, thus requiring skilled and careful workmanship while replacing the affected element with a new one. Such a replacement of the electronic element is time consuming. In addition, the wiring pattern of the PCB 1 may be thermally affected while the solder parts 3 are heated and melted. In the above PCB 1 with the typical surge protector, it is also difficult to detect breakage or deterioration of the surge protector. Another problem of the above surge protector resides in that a thermally affected electronic element fails to be easily discriminated from other normal elements.
In order to test the surge resisting performance of an electronic appliance with a varistor acting as a surge protector, it is necessary to remove the varistor from the appliance prior to testing and mount the varistor in the appliance through a soldering process after the testing, thus being time consuming.


This invention is directed to a semiconductor memory device including a storage element comprising a ferroelectric material or a capacitor dielectric material between a top (plate) electrode and a bottom (stack) electrode. In particular, the invention pertains to the design and fabrication of the stack electrode, which is described as compound because it is comprised of two or more materials which are either patterned separately (with at least one material being deposited and patterned prior to the deposition of the others), or arranged so that each of the component materials significantly contributes to the area over which the ferroelectric or capacitor dielectric is initially deposited. These compound stack electrodes may offer ease in processing, more economical use of noble metal materials, and potentially increased mechanical stability (e.g., resistance to hillocking) relative to solid, single-material electrodes of the same dimensions.

1. Field of the Invention
This invention is directed to stack capacitors for DRAM and FRAM and, more particularly, to a compound electrode stack capacitor, as well as simple processes for fabricating the new stack capacitor electrodes. The electrode structures are made from materials suitable for use with high-dielectric constant materials (e.g., Pt) and are compound because the component parts of the electrode structures are either deposited in separate steps or formed from more than one layer of material.
2. Description of the Prior Art
The incorporation of high dielectric constant materials into small geometry capacitors suitable for Gigabit scale DRAM introduces fabrication challenges relating to topography, electrode material patterning, reaction of high-epsilon materials with Si contact and ultimate density/scalability. Similar challenges pertain to the fabrication of ferroelectric memory cells for ferroelectric RAM (FRAM) and other nonvolatile RAM (NVRAM). Most fabrication schemes for making the electrodes for nonplanar memory cells (a category of devices including both capacitors or "dielectric memory cells" and ferroelectric memory cells) rely on either chemical-mechanical-polishing (CMP) and reactive-ion-etching (RIE). However, these processes to pattern electrode materials such as Pt and other noble metals are still under development; while some processes may eventually be useable in one form or another, there is no guarantee that completely suitable ones will be found.
Suitable electrode materials and fabrication/patterning processes must be developed if high-epsilon dielectric and ferroelectric materials are to be integrated into microelectronic devices. Noble metals and their alloys are often preferred as electrodes for these applications, in part because of their resistance to oxidation during dielectric deposition. However, these materials can be difficult to pattern.
It is an object of the present invention to provide an electrode structure that can be fabricated without CMP or RIE-patterning of a thick electrode layer.
It is another object of the present invention to provide a tall stack electrode having noble metal surfaces and a method of fabrication which does not require CMP or a thick noble metal etch.
It is yet another object of the present invention to provide a noble metal cup electrode whose method of fabrication does not require CMP or fill/etchback.

International Business Machines Corporation


A wrecker truck (100) for transporting disabled vehicles is described. The truck includes an under carriage assembly (24), a subframe (10) and a deck (50). The subframe is preferably tiltably mounted on the under carriage assembly (102). The subframe includes a pair of rails (12 and 13) each having an inner rail member (34) and an outer rail member (36). The rail members are mounted parallel to each other and to the longitudinal axis A--A of the truck such that a slot (38) formed between the rail members extends parallel to the longitudinal axis of the truck. The deck is preferably slidably mounted on the subframe. The deck has a pair of T-shaped sliding members (52) mounted on the bottom side (50B) of the deck. The sliding members have a top cross bar (52A) and a vertical bottom bar (52B). Holding braces (46) having a short leg (46A) and a long leg (46B) are mounted along the length of the rail members such that the top leg extends parallel to the top wall of the rail member. The sliding members are mounted on the rail members such that the vertical bottom bar extends into the slot between the rail members and the top cross bar extends parallel to the top wall (34C, 36C) of the rail members below the holding braces.

(1) Field of the Invention
The present invention relates to a wrecker truck having a tilting and sliding deck for ease in moving a vehicle on and off the deck for transporting the vehicle. In particular, the present invention relates to a wrecker truck having a sliding deck which uses a pair of T-shaped sliding beams which slide along a pair of rails on the subframe to allow the deck to slide along the subframe of the truck.
(2) Description of the Related Art
The related art has shown various wrecker trucks having tiltable and sliding decks for transporting vehicles. Illustrative are U.S. Pat. Nos. 2,753,064 to Lesser; 4,239,275 to Horneys et al; 2,932,418 to Ripley; 3,450,282 to Ezolt; 3,485,400 to Pewthers; 4,353,597 to Shoup; 4,645,405 to Cambiano; 4,756,658 to Moore et al and 4,929,142 to Nespor.
In particular, U.S. Pat. No. 5,246,329 to Farrell shows a flat bed truck for hauling vehicles. The truck has a multi-positional flat bed to assist with loading and unloading. The flat platform for supporting the load has at least two slide rails. The slide rails are slidable on the beams of the frame. The platform also has a pivot platform which allows the bed to extend outward beyond the pivot point of the frame which forms a smaller incline on the bed.
In addition, U.S. Pat. No. 5,249,909 to Roberts et al describes a wrecker truck having dual rails mounted on the frame with I-beams mounted on the deck. The I-beams slide between the pairs of dual rails such that the rails are in contact with both the upper and lower flanges of the I-beams.
Only of minimal interest are U.S. Pat. Nos. 4,988,258 to Lutz et al; 2,576,385 to Bigsby; 2,997,343 to MacKinney et al and Japanese Patent No. 58-194633.
There remains the need for a wrecker truck having a tilting and sliding deck having T-shaped sliding members which allow for easy and controlled sliding of the deck along the rails on the subframe of the truck.


An apparatus includes a chamber configured to support a number of quasi-orthogonal resonant modes, and at least one antenna assembly, where the antenna assembly includes an antenna having a radiating element, where (i) the antenna has predominantly linear polarization of radiation defined by a polarization plane, (ii) the radiating element is disposed within the chamber such that the polarization plane is not parallel and not perpendicular to the plane containing a primary axis of the chamber and a central point of the radiating element, and (iii) each antenna is coupled to the chamber through a designated surface of the chamber and coupled to a source of microwave or radio frequency energy external to the chamber having a nominal operating frequency.

Various apparatuses for processing materials with microwave or radio frequency (RF) energy in closed chambers have been developed for home, commercial and industrial applications. The most well-known example is the ubiquitous microwave oven where, typically, a single source of microwave energy, a magnetron, delivers microwave energy to a rectilinear chamber through a waveguide or waveguide horn antenna with fixed polarization (polarization is a parameter that identifies the orientation of the electric field component the electromagnetic field in space and time). The operating frequency is usually selected as one of the standard industrial frequencies. The selected standard frequency is a result of a compromise between the absorption skin depth in the load material, efficiency of the source (usually a magnetron), and dimensions of both the load and the source including its power supply.
The deficiency in this basic approach is that the distribution of microwave energy is generally very non-uniform and inefficient. The microwave energy density is non-uniform because the resonant modes of the chamber, determined by the frequency of the magnetron and the dimensions of the chamber having typically a single power coupler, create wave patterns that can add both constructively and destructively (the resonant modes are known as Eigenmodes, which are solutions to the electromagnetic wave equations under the boundary conditions imposed by the chamber and the coupler and antenna). As a result, the distribution of microwave energy in the chamber is very non-uniform and the microwave oven generally exhibits hot spots and cold spots in a load. To remedy this deficiency, microwave oven manufacturers have introduced "stirring" mechanisms, which are essentially metallic "propellers" that constantly change the boundary conditions of the chamber to redistribute the microwave energy in the chamber. Another common approach is to provide a rotating food platform that moves the food in and out of the hot and cold spots in an attempt to average out the non-uniformities over the cooking time. The microwave ovens are inefficient because the impedance of the loaded chamber (dominated usually by the water content of the load, its distribution and the volume to be heated) as measured, for example, at the coupler port, is highly variable unlike the impedance of the microwave power source (a basic principal of power transfer efficiency is a match between the impedance of the source and the impedance of the loaded chamber). However, these approaches add cost and complexity, reduce reliability, limit minimum processing time, and are not generally applicable to higher power industrial applications such as heating, drying, sterilization, disinfection, polymerization, and chemical synthesis.
Conventional industrial chambers suffer from the same limitations as microwave ovens, and other limitations as well. Compared to home or commercial microwave ovens, industrial chambers used for heating, drying and chemical synthesis must often operate at much higher power levels (10's of kilowatts versus 1-2 kilowatts). Typically, these chambers are fed by two or more open-ended waveguides or horn antennas that can handle the high power levels, and which are rigidly fixed to the chamber wall. Variations in the load (the material that is being irradiated by the microwave energy), in terms of volume, density, distribution and dielectric constant, for example, can disrupt the distribution of resonant modes in the chamber, resulting in poor uniformity and efficiency. Having more than one coupler in a processing chamber helps to improve uniformity of processing, but also creates problem of mutual influence of these couplers (sources) known as intercoupling or cross-coupling. Additionally, it is very difficult to control cross-coupling between the antennas, which can detune the microwave sources and lead to further losses in uniformity and efficiency.
One approach to overcome these limitations is to employ a single-mode chamber, typically of dimensions smaller than approximately one wavelength, to support only one mode within the operating band of the sources. As a result, the maximum load size in single-mode chambers is less than a cubic wavelength or, for example, about 1 liter at 2.45 GHz. In order to process larger loads, chambers with dimensions larger than approximately one wavelength are required, but existing approaches do not adequately address the limitations of source intercoupling and interference mentioned above.
Other conventional approaches rely on "cross-polarization" between electromagnetic fields radiating from two different sources, which is the condition where the polarization plane, usually defined by the electric field component and direction of radiation propagation, emitted by one radiating element is perpendicular to that emitted by a second radiating element at all points within the volume of interest. Cross-polarized fields do not interfere, even if the corresponding sources are completely synchronized or coherent, such as when two radiating elements are driven by the same source, and so the time average power does not exhibit spatial or temporal interference fringes.
As is known in the art related to closed structures, cross-polarization is usually accomplished in rectangular waveguides or parallelepiped chambers so that the excited mode polarizations are perpendicular at every point (see, e.g., FIGS. 1-2 in U.S. Pat. No. 4,795,871). The '871 patent specifies conical and pyramidal walls that are not parallel or perpendicular but the orientation of the radiators is implied in FIGS. 3-8 as either parallel or perpendicular to the plane containing polar axis and the central point of the radiator.
The analysis in the '871 patent is based on essentially traveling waves propagating as an optical beam in an open space. In the presence of a non-rectilinear, closed chamber of dimensions comparable to approximately ten wavelengths, commonly used in domestic and industrial applications, the fields exist in a form of a discrete set of standing waves exhibiting a pattern of maxima and minima determined by the chamber geometry and its contents. The polarization of these standing waves in general are not mutually perpendicular at all points and therefore it is not obvious that any arrangement of multiple radiating elements can excite non-intercoupled modes.


Among other things, one or more techniques and/or systems are provided for controlling resource access for background tasks. For example, a background task created by an application may utilize a resource (e.g., CPU cycles, bandwidth usage, etc.) by consuming resource allotment units from an application resource pool. Once the application resource pool is exhausted, the background task is generally restricted from utilizing the resource. However, the background task may also utilize global resource allotment units from a global resource pool shared by a plurality of applications to access the resource. Once the global resource pool is exhausted, unless the background task is a guaranteed background task which can consume resources regardless of resource allotment states of resource pools, the background task may be restricted from utilizing the resource until global resource allotment units within the global resource pool and/or resource allotment units within the application resource pool are replenished.

Many computing environments may allow applications to execute background tasks to perform various tasks (e.g., an email application may execute a background task to check for new email; a phone application may execute a background task to receive incoming phone calls while a mobile phone hosting the phone application is in a suspended state; etc.). Unfortunately, background tasks may impact power consumption and battery life because the background tasks may consume resources, such as CPU processing power and/or network bandwidth. Additionally, background tasks may impact a user's experience with a foreground application (e.g., an application visible to a user and/or interacted with by the user) because resource usage by the foreground application may be interrupted by background tasks. Thus, allowing background tasks unfettered access to resources may result in reduced battery life and/or user experience. However, restricting execution of background tasks (e.g., background tasks of suspended applications) may also result in a reduced user experience because various (desired) tasks (e.g., email updates) may not be performed (e.g., when a user "awakens" a tablet device, an email application may comprise stale email information because the email application may have been restricted from executing a background task to check for new emails while the tablet device was "asleep", similarly real-time communication applications, such as VoIP, SMS, and instant messages, may miss and/or be unresponsive to real-time message events while the tablet device was "asleep").


The invention relates to a structural element. In an embodiment, the structural element includes a stiff, elongate tubular member, wherein an inner surface of the tubular member and side faces enclose a core extending along at least a length of the tubular member, wherein the core is provided with a fluid under pressure. The invention furthermore relates to a method for hoisting a stiff, elongate tubular member.

In various industries use is made of structural elements for instance in the form of tubular members. These members are typically manufactured from metal or plastics. The combination of the material and the tubular shape provide structural rigidity to said elements. These elements are furthermore relatively cheap to produce.
By using a plurality of interconnected structural elements it is possible to manufacture a building structure with limited costs while still providing a high rigidity for said structure. This principle is for instance used to manufacture bridges, oil rigs, cranes and other structures having beam-like building elements.

Structural element, structure comprising a structural element and use of said structural element


A method of waiving verification failures is disclosed. The method generally includes the steps of (A) generating a plurality of circuit error files by performing a plurality of physical verifications on a plurality of circuit designs, the circuit error files containing a plurality of circuit errors of the circuit designs, (B) generating a system error file by performing an additional physical verification on a system design, the system error file containing a plurality of system errors of the system design, the system design incorporating the circuit designs and (C) generating a valid error file by removing the circuit errors from the system error file, the valid error file containing a plurality of valid errors comprising a subset of the system errors.

Circuit designs are getting larger and more complex at the 90 nanometer and smaller technology nodes. Because the time to market is shrinking with advancements in technology and product innovation, design teams struggle with meeting tight schedules and remaining under budget. Factoring in Intellectual Property (IP) co-development, a verification methodology that is able to service the criteria of a customer for both quality of results and turnaround time is desired. With IP co-development, not all building blocks for a System-On-a-Chip (SoC) design are available off-the-shelf during an SoC build and integration. As a result, an intelligent "waiver" mechanism for Design Rule Checks (DRCs) pertaining to the IP is often sought. The SoC designers have to integrate IP that is not DRC clean owing to various reasons. For example, the IP received by the SoC designers may lack layer-identifications and/or incomplete verification of the IP at the Graphic Data System II (GDSII) format level. As the IP is being co-developed, some aspects of the IP have not been fully developed and/or validated. Scheduling on the SoC design to make progress at the top (design) level remains a reality even though the IP building blocks are not fully in place. Furthermore, a dynamic nature of process rule specifications create problems, whereby the place and route (i.e., design implementation) systems cannot keep pace and verification does not happen until the very end of the development cycle.

Waiver mechanism for physical verification of system designs


A hollow waveguide for ultraviolet wavelength region laser beams incorporates a glass tube composed of a glass material exhibiting a high transmissivity with respect to ultraviolet rays and an excellent environment resistant property, and a metal film exhibiting a high reflectivity with respect to the ultraviolet rays and formed outside the glass tube. The glass tube serves as an inner surface of the waveguide. The ultraviolet wavelength region laser beams are transmitted while being reflected by the inner surface of the glass tube and by an interface between the glass tube and the metal film.

1. Field of the Art
The present invention relates to a hollow waveguide for transmitting high output ultraviolet laser beams at a high efficiency.
2. Prior Art
Lasers having wavelengths is the ultraviolet region (e.g. an excimer laser) generally have a high energy levels. Those lasers are utilized in a very wide range of applications, such as in laser CVD, surface reforming, photochemical synthesizing and the like. Besides, in the medical field, lasers are employed for in vivo operation in combination with the endoscope. In an industrial field, lasers are used for hyperfine machining.
A requirement essential to utilization of the lasers in the industrial and medical fields is to establish a wave guide technology for guiding laser beams to a desired spot at high efficiency. For example, excimer laser beams having a short wavelength and large peak power are harmful to a living body. However, there exists a difficult problem in terms of transmitting the laser beams safely to a remote part. Thus, it is desired, particularly from the medical sector, that, a waveguide be capable of easily and safely transmitting such laser beams to a position which needs the laser beams.
The following are conventional methods, itemized by (1) through (3), of transmitting high energy laser beams of a laser having a wavelength in the ultraviolet region (e.g., an eximer laser).
(1) A method based on a quartz system optical fiber:
As illustrated in FIG. 6, a core 51 is formed of quartz having a high transmissivity to light in the ultraviolet region. A cladding 52 covering the core 51 is composed of quartz to which an impurity such as fluorine is doped to give thereto a refractive index smaller than that of the core 51. Laser beams l are transmitted while being reflected by an interface between the core 51 and the cladding 52. A hydroxyl group may be doped in the core to reduce the absorption of a specific wavelength. Note that FIG. 6(a) is a cross-sectional view depicting the glass fiber, and FIG. 6(b) is a longitudinal sectional view thereof.
(2) A method based on an aluminum tube waveguide:
An aluminum tube 53, as illustrated in FIG. 7, is obtained by forming aluminum into a tubular shape, exhibiting a high reflectivity to the light of the ultraviolet region. The inner surface thereof is polished to increase the reflectivity. This method uses a so-called hollow waveguide for transmitting the beams l while being reflected by the inner surface of the aluminum tube 53. Note that FIG. 7(a) is a cross-sectional view showing the aluminum tube, and FIG. 7(b) is a longitudinal sectional view thereof.
(3) A method based on an aluminum plate rectangular hollow path:
As illustrated in FIG. 8, the reflection plates are two metal flat plates 54, 54 which are elongate in the light traveling direction. Dielectric spacers 55 are sandwiched therebetween at bilateral ends. A spacing of the hollow path is kept constant. The beams l are transmitted while being reflected by the two metal flat plates 54, 54. These metal flat plates 54, 54 are formed of aluminum having a high reflectivity to light in the ultraviolet region. The inner surface of the hollow path is polished. The dielectric substance serving as a spacer may be formed of Teflon. Note that FIG. 8(a) is a cross-sectional view showing the aluminum plate rectangular hollow path, and FIG. 8(b) is a longitudinal sectional view thereof.
The above-mentioned conventional method (1) based on the quartz system optical fiber, however, presents the following problems. The damage threshold value of an incident end surface against the laser beam is low, although the transmitting efficiency is good. Thus, if an energy density of the incident light is large, the incident end surface is destroyed. Besides, light absorption appears in a wavelength corresponding to an inter-atom bond energy of the material of the core 51. Therefore, in specific wavelengths, the transmissivity is extremely low. In addition, time-variations in the transmissivity become large.
In the method (2) based on the aluminum tube waveguide, the incident power can be increased. However, in this method, the inner surface polishing process becomes harder with a narrower diameter of the waveguide. Besides, the reflectivity of the inner surface decreases with the passage of time due to oxidization, resulting in a drop in the transmitting efficiency.
In the method (3) based on the aluminum plate rectangular hollow path, the incident power can be increased as in the case of method (2). In addition, the inner surface polishing process of the reflection plate can be facilitated. It is, however, difficult to manufacture the path with a smaller sectional area (e.g., 1 mm.sup.2 or thereabouts). Also, as in the case of method (2), the reflectivity of the inner surface drops due to the oxidization, and the transmitting efficiency is thus decreased.

Hollow waveguide for ultraviolet wavelength region laser beams


A device is disclosed for sensing the speed of an EMD 567/645/710 two-cycle diesel engine having a crankcase, electronic fuel injectors and an electronic control system for controlling the electronic fuel injectors. The device includes a spline shaft sized for insertion into the crankcase of the engine so that the spline shaft rotates with the engine, a gear operably secured to the spline shaft to rotate with the spline shaft and sized to rotate with the engine in a 1:1 ratio, and at least one electronic sensor located adjacent the gear to sense rotation of the gear. The at least one electronic sensor is connectable to the electronic control system to provide electronic signals to the electronic control system for determining when to inject fuel with the electronic fuel injectors. Also disclosed is a method for retrofitting the engine and a kit for retrofitting the engine.

As part of the U.S. Environmental Protection Agency's (US EPA) ongoing National Clean Diesel Campaign, the EPA has adopted new standards that dramatically reduce emissions of nitrogen oxide (NOx), diesel particulate matter (PM), unburned hydrocarbon (HC), and carbon monoxide (CO) from locomotive and marine diesel engines. Engines produced from 2005 to 2010 must meet US EPA Tier 2 standards, while engines produced from 2011 to 2014 must meet US EPA Tier 3 standards and engines produced from 2015 and beyond must meet US EPA Tier 4 standards. It is noted that engines produced prior to 1973 were uncontrolled while engines produced from 1973 to 2001 were required to meet US EPA Tier 0 standards and engines produced from 2002 to 2004 were required to meet US EPA Tier 1 standards.
While these EPA standards primarily relate to new and remanufactured engines, there is increasing pressure to reduce emissions of all existing non-road diesel engines. Eventually, all existing locomotive engines produced prior to 1973 must meet the US EPA Tier 0 standards and potentially even lower emission levels. For locomotives operating in specific emissions-regulated locations including California and Texas, emission levels must be reduced further with agreements to encourage the use of engines that meet the US EPA Tier 2 standards.
EMD produced more than 70,000 engines and has the largest installed base of diesel-electric locomotives in both North America and internationally. Among the two-cycle diesel engines produced by EMD are the EMD 567 series which was produced from 1938 until 1966 and the EMD 645 series which was produced from 1965 until 1988. The EMD 710 series which was produced from 1985 and is still produced currently. The EMD 567/645/710 engines can be used for long periods of time due to their ability to be repeatedly repaired/overhauled and the high cost of newly purchased engines.
There is a large population of EMD 567/645/710 engines in service that have not reached the end of their useful life—a unique feature of this engine segment compared to smaller engine models. Some existing engines may exceed fifty years of age. Because of the emission standards, however, the owners of these EMD 567/645/710 engines are faced with the option of either overhauling or rebuilding the engines to meet the newer emission standards or retiring the engines early and purchasing new technology engines that meet the current emission standards. As a result, the owners of these engines stand to incur a heavy financial loss. Accordingly, there is a need for a cost effective system and method for extending the useful life of these two-cycle diesel engines without requiring an expensive overhaul or new replacement engine.
One method for reducing the emissions on these engines involves the installation of electronic fuel injection. The current system utilizes mechanical injection where the injection is determined based on machined dimensions that are fixed, and do not vary during the use of the product. Electronic injection allows flexibility by varying the injection based on numerous inputs. Some of these inputs may include ambient temperature, altitude, geographic location, and so forth. Since the injectors are no longer fixed mechanically they require input from the engine as to the speed and position of the drive-train to determine with accuracy the time to begin, hold, and end, injection. New engines with electronic fuel injection incorporated in to the design utilize the flywheel for the monitoring and measurement of speed and RPM. The utilization of a once per revolution sensor to sense the absolute position, and then the monitoring of the flywheel teeth for synchronizing the position during the revolution is done utilizing two sensors on the flywheel. The concern with this prior art is that the sensors have a history of being damaged and moved due to their location in an area of the engine that is frequently accessed by mechanics. Accordingly, there is a need for an accurate device for monitoring and measuring the speed and position of these two-cycle diesel engines that can be easily installed in a retrofit or new application and in a position for reliable operation.

Speed and position sensing device for EMD two-cycle diesel engines


A re-usable road surface, consisting of soil-repression-bodies to be placed on the provisional ground surface with a certain mutual distance and link-elements between the bodies, whereby each body is formed as a plate-shaped part with circular or multi-angular shape and therebelow a rigid repression part, the plate-shaped part being provided with means for arranging the flexible link-elements, whereby the bodies are arranged in mutually staggered rows and each body is connected with adjacent bodies in other longitudinal or transversal rows by said link-elements.

The invention relates to a re-usable road surface, consisting of soil-repression-bodies to be placed on the ground surface with a certain mutual distance and link-elements between the bodies.
A similar provisional road surface is for example known from EP-A-0286 396, where each soil-repression body in top view has an ablong rectangular form and the bodies are arranged in one row, whereby the link-elements are arranged in two parallel longitudinal rows between the bodies. Such a provisional road surface is arranged as a roadway in two adjacent paths, so that vehicles or the like can move thereon. Thus this provisional road surface has a very restricted width.

Nederlandse Organisatie voor Toegepast-Natuurwetenschappelijk Onderzoek Tno


The present invention is directed to curable film-forming compositions comprising a first film-forming polymer prepared from at least one hydrophobic monomer, a second film-forming polymer prepared from at least one hydrophobic monomer, and a curing agent. Upon application of the curable film-forming composition to a substrate to form a coating layer, the first film-forming polymer is distributed throughout the coating layer, and the concentration of the second film-forming polymer is greater at the surface of the coating layer than the concentration of the second film-forming polymer within the bulk of the coating layer. The invention is additionally drawn to substrates coated with the curable film-forming composition. The present invention is also drawn to methods of mitigating dirt build-up on a substrate, comprising applying to at least a portion of the substrate the curable film-forming composition described above and at least partially curing the curable film-forming composition.

Easy cleaning of coated surfaces is a significant selling point for many industries, in both consumer and industrial markets. Easy removal of dirt and prevention of dirt build-up are desirable properties for products such as automobiles. Environmental contaminants such as tar, asphalt, animal droppings, road salt, detergents, and the like may damage the surface of coated vehicles, architectural surfaces, and other industrial substrates. Damage may be caused by a chemical reaction of the contaminant with the coated surface such as by chemical etching, or may involve physical removal of part or all of the coating from the substrate (i. e., "cohesive failure") upon removal of the contaminant during cleaning. Cohesive failure may also involve incomplete removal of the contaminant from the coated surface during cleaning.
The use of hydrophobic acrylates as additives has been the main approach to yield easy-to-clean "E2C" coatings such as automotive clearcoats. However, incompatibility of conventional film-forming binders, which tend to be hydrophilic, and the hydrophobic additives limits the applicability of this approach, because stratification of the materials upon application to a substrate leads to irregular distribution of the hydrophobic additive as well as an undesirable increase of haze. Additionally, short duration of the dirt mitigation properties of current E2C compositions, due to poor durability, has limited their use.
It would be desirable to provide coating compositions that may be used in methods of mitigating dirt build-up on a substrate in order to overcome the disadvantages of the prior art.

Curable film-forming compositions prepared from multiple hydrophobic polymers and method of mitigating dirt build-up on a substrate