The invention relates to an electric machine (10), in particular a generator for a motor vehicle, comprising an exciter system composed of a plurality of electrically excited salient poles. The salient poles can be designed within the stator (16) or rotor (20) in the form of electromagnetically excited poles (22, 23; 24, 25) which are axially and radially oriented on the periphery and are alternatively polarized in the peripheral direction. In order to improve performance and reduce the magnetic leakage flux, permanent magnets (66), which are secured by means of a magnetically non-excitable holding element (60), are inserted into interstices (74) between the alternating poles (24, 25). The holding element (60) is bilaterally mounted in pole grooves (92, 94), is radially, axially, and tangentially resilient, and has a wave-shaped (62) and/or bead-shaped (76, 78; 86) profile.

The German patent publication DE 10 2006 041 981 A1 relates to an electric machine. The electric machine relates particularly to an electrically excited claw-pole generator for a motor vehicle. The claw-pole generator comprises a rotor having a plurality of axially oriented poles which alternate magnetization in the peripheral direction and permanent magnets disposed between the poles for increasing performance and reducing the magnetic leakage flux. The permanent magnets are secured by means of non-magnetic plates bilaterally held in pole grooves. These plates comprise in each case at least one additional locking mechanism with which they are supported in the axial direction at the poles. The additional locking mechanisms are, for example, designed as sheet metal tabs which are bent or angled and are supported in a resiliently clamping manner at least one axial end section of the poles.
The German patent publication DE 199 51 115 A1 likewise relates to an electric machine. This electric machine relates to a generator for a motor vehicle having an exciter system and a plurality of electrically excited salient poles in the stator or rotor. The stator as well as the rotor thereby comprises the form of electromagnetically excited poles which are axially oriented on the periphery and are alternatively polarized in the peripheral direction. In order to reduce magnetic leakage flux, permanent magnets are situated in the interstices between the poles. The permanent magnets are inserted into the aforementioned interstices. Said permanent magnets on the stator, respectively the rotor, are secured in such a way that they are in each case held by means of a magnetically non-excitable holding element. This holding element is bilaterally mounted in pole grooves in the tangential and axial directions by means of caulking; and a pole groove is longitudinally incorporated into one pole and a pole groove is longitudinally incorporated into an opposite pole. In the case of a rotor, the holding element covers the respective permanent magnet in the radial direction to the stator or in the case of a stator in the radial direction to the rotor with a base section. Bent tabs, which exert a clamping force on axial front faces of the inserted permanent magnets, are located at each of the opposite ends of the base section.
In the case of electric machines as those known from the German patent publications DE 19 2006 041 981 A1 and DE 199 51 115 A1, the claw poles of a claw-pole machine tend to bend up radially outwards at high rotational speeds >20,000 rpm. This deformation occurs more or less dramatically, in each case depending on the rotational speed of the electric machine.


The present invention provides a method and system for reducing fragmentation (both file fragmentation and free-space fragmentation) in digital storage devices (10). In such a device in which a plurality of files is available for deletion the invention proposes selectively deleting the file that maximises defragmentation. The selection may optimise file and free-space defragmentation.

The present invention relates to methods of and systems arranged for reducing fragmentation. The invention also relates to corresponding computer program products.
A digital storage device is typically a disk on which data is stored. The present invention is concerned with such storage devices in which the data storage is potentially temporary, i.e. data is deletable.
When data, in the form of files, is stored to such a disk it is done so that each file is independently accessible. The files are stored on tracks arranged concentrically on the disk. The location on the disk at which a particular file is located is stored in a separate data structure in a disk management file.
Files are saved to the disk in one or more fragments. A fragment contains part or all of a file. When a large file is to be stored on the disk, several fragments may be required. Depending on the available space on the disk the fragments may be scattered around the disk surface. If the disk is near its capacity for data storage, even a relatively small file may have to be split into spaced fragments.
This spacing of fragments of a file is referred to as file fragmentation. When the free space between fragments becomes fragmented, this is referred to as free-space fragmentation. A highly fragmented disk generally will take longer to read as the read device needs to hunt around the disk to find the relevant fragments. Similarly it can take longer for a file to be saved to a highly fragmented disk as the write device needs to find sufficient fragments for all of the file(s), which clusters may be widely spaced. File fragmentation and free-space fragmentation are together referred to as fragmentation.
Various approaches have been tried to reduce fragmentation of such a memory device, for instance as disclosed in U.S. Pat. No. 5,930,828. In this prior art proposal files are moved around the disk to reduce fragmentation. This is time consuming and processor intensive.
In recent digital devices such as disk based digital video recorders using a file system, it is often the case that a file is to be deleted. For instance, a user may pre-select files for deletion (similar to a xe2x80x9crecycle binxe2x80x9d in a WINDOWS (trade mark) operating system environment) or files may be annotated only to be kept for a certain period of time. Such annotation is recorded in the system file manager usually by a marker flag. In this case there may be a plurality of files available for deletion when a delete operation needs to be carried out, for instance, to create space for a new file to be saved.
When a delete operation is necessary, it is desireable permanently to delete the minimum number of files so that (a) at least the required amount of free space is created; and (b) defragmentation and free-space defragmentation are optimised.
It is an aim of preferred embodiments of the present invention to provide a method, system and corresponding computer program product for reducing fragmentation of a digital storage device.
According to the present invention in a first aspect, there is provided a method of reducing fragmentation of a digital storage device, characterised by the method comprising the steps of:
determining that a plurality of files is available for deletion;
selecting one of the files; and
deleting the selected file and not deleting another of the files.
According to the present invention in a second aspect, there is provided a system arranged for reducing fragmentation of a digital storage device, characterised by the system comprising means for determining that a plurality of files is available for deletion; means for selecting one of the files; and means for deleting the selected file and not deleting another of the files.
It has been realised that with digital storage devices annotating a plurality of files for deletion, there is an efficient opportunity to reduce fragmentation by selective file deletion.

Method and system for reducing fragmentation


An optical unit or an optical sensor through which a light beam is propagated in a predetermined direction, having an optical component which includes at least one first single crystal element each having a property of causing dextrorotation of a plane of polarization of the light beam during propagation of the beam, and at least one second single crystal element each having a property of causing levorotation of the plane of polarization of the light beam. The first and second single crystal elements are superposed on each other in a direction perpendicular to the direction of propagation of the beam. The single crystal elements may be bonded together by direct solid-solid reaction, or by diffusion of a material of a thin bonding film interposed between the adjacent single crystal elements. The single crystal elements also exhibit a magnetooptical or Faraday effect when used in a magnetic-field sensor, for example.

1. Field of the Invention
The present invention relates to an optical component consisting of a single crystal element or elements having a property of causing dextrorotation (clockwise rotation) of a plane of polarization of a light beam propagated therethrough, and a single crystal element or elements having a property of causing levorotation (counterclockwise rotation) of the beam polarization plane, or an optical magnetic-field sensor including an optical component consisting of a single crystal element or elements having the properties of causing the dextrorotation of the polarization plane and producing a magnetooptical effect or the Faraday effect, and a single crystal element or elements having the properties of causing levorotation of the polarization plane and producing the magnetooptical effect or the Faraday effect.
2. Discussion of the Prior Art
As one optical component of an optical unit, there is known an optical component of a type which consists of a single crystal element having a property of causing dextrorotation of the plane of polarization of a light beam during propagation of the beam through the element, and a single crystal element having a property of causing levorotation of the polarization plane of the beam. An example of such an optical component is disclosed in laid-open Publication No. 58-140716 of unexamined Japanese Patent Application, which uses a first single crystal of BSO (Bi.sub.12 SiO.sub.20) or BGO (Bi.sub.12 GeO.sub.20) which has a property of causing an incident plane-polarized light beam to undergo dextrorotation of the polarization plane, and a second single crystal of BSO or BGO which has the same effective length as the first single crystal and which has a property of causing the light beam to undergo levorotation of the polarization plane. These first and second single crystals are bonded together in series in a direction of propagation of the light beam through the optical element, so that the properties of causing the dextrorotation and levorotation of the beam polarization plane may be offset or canceled by each other, so as to substantially eliminate an influence of the optical rotatory powers of the light beam while the beam is propagated through the single crystals.
Another type of optical component is disclosed in laid-open Publication No. 61-250572 of unexamined Japanese Patent Application. This optical component uses a first single crystal element having properties of causing the dextrorotation of the polarization plane of a beam and producing a magnetooptical effect or Faraday effect (polarization plane rotation of a beam when passing through the element in a magnetic field), and a second single crystal element having the properties of causing the levorotation of the beam polarization plane and producing the magnetooptical effect or the Faraday effect. These first and second single crystal elements are bonded together in series in the direction of propagation of the light beam. By adjusting the effective lengths of these single crystal elements, the temperature characteristic of the optical rotatory powers of the beam propagated through the elements may be canceled by the temperature characteristic of the magnetooptical effects of the elements, so as to minimize the temperature dependence of the optical component as a whole.
Usually, the intensity of the light beam which has been propagated through or emitted from such an optical component is used as a parameter or variable to be detected. Accordingly, it is desirable to minimize the amount of attenuation of the light while the light is propagated through the optical component (single crystal elements).
In the optical component as disclosed in the above-identified publications (Japanese laid-open publications Nos. 58-140716 and 61-250572), however, a bonding interface between the first and second single crystal elements having different optical properties acts as a reflecting surface since the two elements are disposed in series in the direction of propagation of the light beam, i.e., since the plane of bonding or adjoining interface of the two elements is perpendicular to the beam propagation direction. Consequently, the bonding interface necessarily increases the total number of the surfaces of the optical component (including the end faces of the single crystals) by which a certain portion of the light beam is reflected. Accordingly, the ratio of the portion of the light beam reflected by the optical component, to that of the beam transmitted through the component, is increased. Thus, the light beam is considerably attenuated while it is transmitted through the optical component. Where the optical component is used in an optical sensor whose output is determined by the intensity of the light beam emitted from the optical component, for example, in a magnetic-field sensor (as disclosed in the above-identified publications) for detecting the magnitude of a magnetic field to which the optical component is exposed, the sensing accuracy or sensitivity of the sensor inevitably tends to be lowered due to the attenuation of the light beam during propagation through the optical component. That is, the known optical component or sensor suffers from the relatively low sensitivity or sensing accuracy.
The optical component indicated above is incorporated in an optical unit of an optical device such as a magnetic-field sensor as disclosed in the publications identified above, which optical unit includes other optical components such as a polarizer and an analyzer. The single crystal elements of the optical component in question usually interposed between the polarizer and analyzer generally consist of single crystals each of which exhibits a magnetooptical or Faraday effect in the presence of a magnetic field, as well as exhibits the property of causing dextrorotation or levorotation of the plane of polarization of a light beam in the absence of a magnetic field.
In the optical magnetic-field sensor indicated above, the optical rotatory powers and the magnetooptical effects of the single crystal elements are influenced by or changed with a variation of the operating temperature of the sensor. To reduce the sensing error arising from this temperature variation, it is desirable that the temperature dependence of the rotations of the beam polarization plane be canceled by the temperature dependence of the magnetooptical effects, as proposed in the laid-open Publication No. 61-250572.
As pointed out above, however, the known optical magnetic-field sensor disclosed in the Publication No. 61-250572 suffers from the reflection of a relatively large portion of the incident light beam by the bonding interface of the first and second single crystal elements as well as by the end faces of the elements, because the bonding interface of the two elements having the different optical properties is normal to the direction of propagation of the light beam. Further, the arrangement of the optical sensor in question inherently has a certain slight residual difference in the angle of rotation due to the optical rotatory powers between the first and second single crystal elements. When the relevant optical component and the analyzer are disposed such that the plane of polarization of the light beam emitted from the optical component is rotated by 45.degree. with respect to the plane of incidence of the analyzer about the optical axis of the sensor, the latter plane must be finely adjusted so as to compensate for the residual difference between the angles of rotation of the light polarization plane of the single crystal elements. This complicates the assembling procedure of the optical unit of the sensor.

Optical component and magnetic-field sensor using superposed single crystal elements having different optical properties


Scalable implementations of exact distinct counts and multiple exact distinct counts in distributed query processing systems are implemented via systems and devices. Distinct counts and multiple exact distinct counts for identifiers/values are performed based on keys. For distinct counts, datasets including data fields are sorted by values of fields and divided into balanced partitions in distributed servers. Subsets of fields with the same value are partitioned together. Key presence is determined for subsets on each partition, and the number of instances for the key are aggregated for exact distinct counts of values. For multiple distinct counts, fields of a dataset are combined by un-pivoting field columns. Compound keys are generated for combined fields from field identifiers of the combined fields and values of another field. Totals of unique values of the combined fields are determined for values in the counted field based on the compound keys.

In databases, counts of distinct identifiers/values return the number of unique values for a given field of the data. For very large input datasets, like big data, random partitioning of the data (e.g., round robin schemes) collects all the distinct values, when the number of distinct values is relatively small, in a hash table indexed by the keys, one per partition, and merges all hash tables to provide a result via cardinality. In other solutions, the data is partitioned on groups by keys, having high distinctness, and the value field. The data is then grouped by the keys/values and then counted—per partition and then summed.
In performing multiple counts of different distinct identifiers/values on the same input dataset, each count of a distinct value is done separately, then the different results are combined with a group by keys operation. Such operations require an extra partition of the data in addition to having a partition for each different count. That is, one partition for each of the counts and one partition for a final count are required to combine the results together.


The present invention is directed to a twist drill which is coated with a layer of CVD diamond and which has slots in its head which are filled with CVD diamond. The invention twist drill is made by forming slots in the head of the twist drill and then subjecting the slotted twist drill to a CVD diamond deposition process for coating said twist drill with a layer of CVD diamond and for filling said slots with CVD diamond. The performance of CVD diamond-coated twist drills does not depend on retaining the diamond film over most of the areas of the drill; but, rather, drill performance is dependent upon retaining a layer of diamond on the cutting edge of the drill. The diamond-filled slots in the head of the twist drill function as wear stops and additional cutting edges as the surrounding drill material is worn away during use.

The present invention relates to diamond coated workpieces and more particularly to an improved CVD diamond coated twist drill.
Its hardness and thermal properties are but two of the characteristics that make diamond useful in a variety of industrial components. Initially, natural diamond was used in a variety of abrasive applications. With the ability to synthesize diamond by high pressure/high temperature (HP/HT) techniques utilizing a catalyst/sintering aid under conditions where diamond is the thermally stable carbon phase, a variety of additional products found favor in the marketplace. Polycrystalline diamond compacts, often supported on a tungsten carbide support in cylindrical or annular form, extended the product line for diamond additionally. However, the requirement of high pressure and high temperature has been a limitation in product configuration, for example.
Recently, industrial effort directed toward the growth of diamond at low pressures, where it is metastable, has increased dramatically. Although the ability to produce diamond by low-pressure synthesis techniques has been known for decades, drawbacks including extremely low growth rates prevented wide commercial acceptance. Recent developments have led to higher growth rates, thus spurring recent industrial interest in the field. Additionally, the discovery of an entirely new class of solids, known as "diamond like" carbons and hydrocarbons, is an outgrowth of such recent work.
Low pressure growth of diamond has been dubbed "chemical vapor deposition" or "CVD" in the field. Two predominant CVD techniques have found favor in the literature. One of these techiques involves the use of a dilute mixture of hydrocarbon gas (typically methane) and hydrogen wherein the hydrocarbon content usually is varied from about 0.1% to 2.5% of the total volumetric flow. The gas is introduced via a quartz tube located just above a hot tungsten filament which is electrically heated to a temperature ranging from between about 1750.degree. to 2400.degree. C. The gas mixture disassociates at the filament surface and diamonds are condensed onto a heated substrate placed just below the hot tungsten filament. The substrate is held in a resistance heated boat (often molybdenum) and heated to a temperature in the region of about 500.degree. to 1100.degree. C.
The second technique involves the imposition of a plasma discharge to the foregoing filament process. The plasma discharge serves to increase the nucleation density, growth rate, and it is believed to enhance formation of diamond films as opposed to discrete diamond particles. Of the plasma systems that have been utilized in this area, there are three basic systems. One is a microwave plasma system, the second is an RF (inductively or capacitively coupled) plasma system, and the third is a d.c. plasma system. The RF and microwave plasma systems utilize relatively complex and expensive equipment which usually requires complex tuning or matching networks to electrically couple electrical energy to the generated plasma. Additionally, the diamond growth rate offered by these two systems can be quite modest.
Heretofore, CVD diamond has been coated onto tungsten carbide or other substrates to make cutting tool inserts (U.S. Pat. Nos. 4,707,384 and 4,731,296) or co-deposited with boron or another element for making semiconductors (e.g. EP Publications Nos. 286,306 and 282,054). Commonly-assigned application Ser. No. 563,367, filed Aug. 7, 1990, discloses a CVD reactor especially adapted to coat twist drills with a layer of CVD diamond.


A fast switching, variably polarized lens is placed in front of a radar antenna which radiates an electromagnetic wave having any fixed polarization. The radiated electromagnetic wave is coupled to the lens and the switching elements within the lens transform the polarization of the radiated electromagnetic wave as commanded. Each transmit pulse may take on any polarization which the lens is capable of providing independent of the polarization of the previous transmit pulse. Similarly, during receive mode the lens can be set up to allow the radar system to receive a return signal of any polarization independent of the polarization of the return signal's associated transmit signal.

In the field of radar design there is an ever existing emphasis on increasing both the detection and identification capability of the radar. This has lead to designs utilizing narrower and narrower pulses of transmitted electromagnetic energy to break out more features (i.e., increase the resolution) associated with a target. However, narrow pulse systems are prohibitively expensive, especially baseband pulse systems.
One solution which increases the radar system's detection capability utilizes a polarization diverse antenna systems capable of transmitting and receiving pulses of various polarizations. In practice however, these systems are often very complex, unacceptably heavy and physically too large for use in airborne applications. As an example, U.S. Pat. No. 3,720,947 assigned to the United States government discloses a mechanical switching system for changing the polarization of a radar antenna to either a linear, circular right or circular left polarization. This mechanical switching system is not compatible with recent requirements for airborne radar systems, especially a fighter aircraft radar system. In addition, the mechanical switching system is too slow to allow a radar system to switch polarization on a pulse to pulse basis.
One way to provide a polarization diverse radar system is to provide a lens in front of a radar antenna to switch the polarization of the radiated and received electromagnetic waveform to the desired polarization. U.S. Pat. No. 4,901,086 assigned to the Raytheon Company discloses a radar system incorporating a lens which transforms a linearly polarized waveform to a circularly polarized waveform on transmit, and transforms a circularly polarized waveform to a linearly polarized waveform on receive. However, this system does not have the flexibility to vary the polarization of the transmit and receive waveforms on demand, or pulse to pulse.

Fast switching polarization diverse radar antenna system


A sealing member or inner seal for a sealing to a rim of a container is described herein that is capable of initially providing sealing for the container and subsequently for providing a dispenser or dispensing feature having a cleanly formed opening or other passage therethrough for dispensing container contents. The sealing members or inner seals herein are constructed from flexible sheets or laminates defining one or more integrated or preformed dispensing feature(s) or element(s) for dispensing contents from the container. The one or more integrated dispensing feature(s) or element(s) are initially covered on both sides to be exposed for use upon removal of a portion of the sealing member.

Many containers are provided with a finish or fitment having perforations or a pour spout for dispensing contents from the container. Spice containers and salad dressing bottles are some examples that include such features. Other types of containers, bottles, and packages may also include similar covers, finishes, or fitments.
A spice container, for example, often includes a molded snap-on cover or fitment that extends across an opening or mouth of the container. The cover or fitment is a relatively rigid plastic piece that is molded into a desired shape. It fits over the container's mouth and resides underneath a screw cap. This molded snap-on cover or fitment often includes several holes or perforations for dispensing a spice, powder, food ingredient, or other granulated product in the container. These containers often include a seal liner underneath the perforated cover or fitment in order to maintain the freshness of the product held in the container prior to use by a consumer. In order to dispense the contents, a consumer first must remove the rigid, molded cover or fitment in order to gain access to the seal liner. Once the cover or fitment is removed, the seal liner can be peeled from the container. Then, the molded perforated cover or fitment must be replaced on the container prior to dispensing its product.
Similarly, salad dressing bottles can have a rigid, molded cap and/or fitment that define a pour spout for ease in pouring a liquid product out of the bottle. Like the spice container, the salad dressing bottle may also include a seal liner underneath the cap or fitment. In use, the cap and fitment must first be removed by the consumer in order to remove the seal liner prior to its first use. Then, to use the bottle as intended, the cap and fitment are replaced on the bottle.
These assemblies suffer several shortcomings. As the container or bottle is supplied to the consumer with the seal liner underneath the molded fitments, in order to use the container as intended, the consumer must first remove the molded fitment in order to gain access to the seal liner. In many cases this is undesirable due to the extra steps required by the consumer to first, remove the cap; second, to remove the fitment; third, to remove the seal liner; fourth, to replace the fitment; and fifth, to replace the cap. As the fitments are generally rigid molded plastic, they may be difficult to remove and then replace tightly back on the container. Oftentimes, they may crack or deform upon removal. In addition, these assemblies require additional manufacturing steps to mold and assemble the container with the additional pieces.
Other containers may have a two-component seal or liner having an upper, peelable portion that exposes an opening in a lower liner portion upon removal of the upper, peelable portion. The lower liner portion includes the opening extending all the way through. The opening is covered by the upper, peelable portion that is glued or otherwise held to the lower liner portion with adhesive. In this approach, however, the ability of the two-component liner to form a good seal to maintain product freshness prior to a consumer peeling off the upper, peelable portion is limited by the nature of the glue or adhesive holding the upper portion to the lower liner portion. Because the opening in these prior seals extends all the way through the lower liner portion, the adhesive or glue holding the upper, peelable portion to the lower liner portion could allow penetration of air, moisture, oxygen, and the like into the container depending on the nature and characteristics of the adhesive or glue.
Other containers may have an opening defined in a rigid upper wall, such as a pour opening defined in an aluminum upper wall of an aluminum beverage or juice container. Some prior approaches may also include two flexible liners covering the opening. One flexible liner is adhered to the inside aluminum upper wall and covering one side of the opening, and the other flexible liner is adhered to the outside aluminum upper wall and covering the other side of the opening. The two liners are adhered to each other through the opening. During use, a consumer removes the outer liner, which pulls the inner liner through the opening. This action tears the inner liner on the sharp edges defining the opening in the aluminum wall. In this prior approach, it is relatively easy to pull and tear the inside liner due to the rigid nature of the top aluminum wall and the sharp cutting edges that the aluminum forms about the opening.
Rather than using a rigid upper wall to define an opening, some other prior approaches may utilize flexible inner seal type structures that define an opening in a flexible layer forming the inner seal. The inner seal may include a peelable, upper layer covering one side of the inner seal opening, and a lower layer covering the other side of the opening. The peelable, upper layer and the lower layer may be adhered to each other through the inner seal opening. Similar to the removal action with regards to the aluminum can or container noted above, a consumer can peel off the peelable, upper layer to pull the lower layer through the opening defined in the flexible inner seal. This action tears the lower layer to expose the opening for use. In this approach, however, when the opening is defined in a flexible inner seal (rather than the rigid layer of the cans discussed above), the tearing of the lower layer often forms an unappealing opening due to frayed or ragged edges in the lower layer because the flexible nature of the inner seal. The flexible layers used to form the inner seal and define the opening therein do not offer sufficient rigidity to form a clean tear in the lower layer upon the pulling action.

Sealing member with removable portion for exposing and forming a dispensing feature


A device for converting light from, for example, a laser, VCSEL (vertical cavity surface emitting laser) or light emitting diode/diodes to a plane of propagation, comprising a collimated or focused light emitter, characterized in that a full or a portion or several portions of a rotational symmetrical double reflecting component is fixedly provided coaxially in the path of beams from the collimated or focused light emitter so that the light is deflected in a desired angled plane of propagation which extends up to 360° around the double reflecting component.

This has previously been solved by means of a device with a light source whose light beam has been angled by means of a rotating prism or mirror, which rotates 360° so that the rotating beam describes a plane of propagation around the device.
A problem with these known devices is that they require very accurate manufacturing so that the rotating parts do not angle the light beam incorrectly during the rotation. Additionally, at least one motor is needed to rotate them.
Another problem is that they are provided within four windows, which lead to four corner pillars for the holding of the windows, which blocks the propagation of the light plane. An attempt to get away from the problem with rotating parts and motors has been done in U.S. Pat. No. 3,820,903. In that the rotating parts have been replaced by a conical, reflecting prism which deflects a laser beam 90° so that a plane is formed 360° around the prism.
A problem connected with the use of a reflecting cone is that the device becomes very sensitive to angle deviations of the cone relative the incoming light beam since a small angle deviation there is enlarged in the plane of propagation, see FIG. 1b. The angle error will be doubled according to the law of reflection. A small angle error may at long distance give large position errors.


A mechanic's creeper and headrest apparatus includes a frame, a plurality of wheels or casters, a back support, and a movable headrest, and includes an electric motor-driven mechanism such as a linear actuator, cylinder, ram, rack, screw, gear, or other mechanism operable to raise and lower the headrest to a desired tilt or height. The electric motor-driven mechanism is preferably connected to a rocker switch mounted on the frame such that the user can selectively raise and lower the headrest with one hand by manipulation of the rocker switch. The frame also preferably includes a power switch and a battery to provide power to the electric motor drive mechanism.

Many current creepers for use primarily by mechanics and others include a frame of longitudinally extending metal rails which carry four or more casters and which have metal cross members extending between them. A flat pad is positioned on the cross members to support the user. At times, a thickened area of the pad is provided at one end of the pad which is intended to be a headrest for the user. However, these types of creepers have often proven to be uncomfortable to the user.
The foregoing information reflects the current state of the art of which the present inventor is aware. Reference to, and discussion of, this information is intended to aid in discharging Applicant's acknowledged duty of candor in disclosing information that may be relevant to the examination of claims to the present invention. However, it is respectfully submitted that none of the above-indicated information discloses, teaches, suggests, shows, or otherwise renders obvious, either singly or when considered in combination, the invention described and claimed herein.


A purpose is to enable detection of an object in a display device including a display panel provided with photosensors when the object touches the display panel and when the object does not touch the display panel. A display device includes a display panel provided with photosensors. The display device has a function of detecting an object with the photosensor when the object touches the display panel and when the object does not touch thereto. The display device has a function of changing the sensitivity of the photosensor varies depending on whether the object touches the display panel.

1. Field of the Invention
The present invention relates to a display device including a photosensor and a driving method of the display device. In particular, the present invention relates to a display device in which pixels each provided with a photosensor are arranged in matrix and to a driving method of the display device. Further, the present invention relates to an electronic device including the display device. In addition, the present invention relates to a semiconductor device and a driving method thereof.
2. Description of the Related Art
In recent years, a display device provided with a touch sensor has attracted attention. The display device provided with a touch sensor is called a touch panel, a touch screen, or the like (hereinafter referred to simply as a touch panel). Examples of the touch sensor include a resistive touch sensor, a capacitive touch sensor, and an optical touch sensor which are different in operation principle. With the touch sensor, an object (e.g., a pen and a finger) touching a display device can be detected. Therefore, data for controlling the display device can be input by the use of the touch sensor as an input device. In addition, a display device including an optical touch sensor can be also used as a contact area sensor (e.g., Patent Document 1).
Further, as an example of a device without a display panel, a semiconductor device such as an image sensor can be given.

Semiconductor Energy Laboratory Co., Ltd.


An apparatus and associated method, the apparatus comprising a controlled element (10), such as a robotic manipulator, and a dynamically updatable control system (11). The control system (11) uses a control system equation (eq. (1)) to determine control signals (dq/dt) for controlling the controlled element (1) given any required inputs (q, V) to the control system equation (eq. (1)). The control system (11) is dynamically updatable in that in response to a script file indicating a code structure (11d) preferably having linked nodes (12a 13a-c) and representing at least some components (W,F,xcex1,xcex2) of the control system equation (eq. (1)), the control system (11) creates the code structure (11d), at run-time, and does so such that the nodes (12a 13a-c) can be queried (i.e. are executable logic) to provide values for at least some components (W,F,xcex1,xcex2) of the control system equation (eq. (1)).

The present invention pertains to the field of control systems for remote autonomous agents, and in particular to dynamically reprogramming control systems of remote autonomous agents, such as, e.g., dynamically reprogramming the velocity control system of a remote robotic manipulator.
Autonomous agents, including e.g. robotic manipulators, often act (or execute instructions) according to embedded control software implementing one or more algorithms. For example, algorithms developed for robotic manipulators (such as arms and hands) are typically implemented in embedded object code that has been precompiled and then loaded onto a computer processor residing in the manipulator. To change an existing. algorithm or to add a new algorithm, the corresponding control software must be compiled and loaded into the processor, and in case of the autonomous agent already operating at a remote location, the compiled object code must first be communicated to the processor.
It is not infrequent that changes are made to fielded control systems of autonomous agents; fielded control systems are often complex, with many patches and logical paths added over the years. Even discounting innovations in the algorithms used by control systems, a control system for an autonomous agent may need to be modified on account of failure of part of the autonomous agent. For example, a joint of a robotic manipulator arm may fail, and the algorithm used for control may have to be modified so that the robotic manipulator may continue to do useful work.
In view of the inevitability of the need for changes to control systems of autonomous agents, what is needed is a way to more quickly and simply reprogram such control systems, even when the autonomous agents are remotely fielded.
Accordingly, in a first aspect of the invention, an apparatus is provided, comprising a controlled element and a control system, the control system using a control system equation to determine control signals and the control system then providing the control signals to the controlled element, the control system implemented so as to include executable elements operative according to coded instructions, the apparatus adapted so as to load the executable elements at power on into a memory device from which coded instructions are then obtained by which the control system is operative, the apparatus characterized in that the control system comprises: a controller, comprising static controller code elements and responsive to a script file indicating a code structure, for providing at least some components of the control system equation, the controller for creating the code structure in the memory device; wherein, in providing the code structure, the controller parses the script file so as to create the code structure in the memory device or in a memory device holding auxiliary memory, and imparts to the code structure executable logic enabling the code structure to return a set of one or more values when queried.
In accord with the first aspect of the invention, the code structure may be a code tree structure including a root node and also linked branch and leaf nodes forming branch structures terminating in the leaf nodes and leading downward away from the root node, and each node of the code tree structure may include an expression element described by the script file, and further wherein each expression element may include executable logic enabling the expression element to return a set of one or more values when queried, and to read and write to a data stream its description including all expression elements below it in the code tree structure. Further, the script file may be a hierarchical script file according to a hierarchical scripting language. Also further, the controlled element may be a robotic element, and may be, more particularly, a robotic manipulator. Further still, the control system may be a velocity controller. Still further, the control system equation may comprise a core control system equation providing values for {dot over (q)} given by:             q      .        =                            [                      J                                          N                J                T                                          W                                ]                          -          1                                  [                  V                                    -              α                                                  xe2x80x83                                                  N              J              T                                    F                          ]              ,
in which: V is a vector of length m indicating motion of a point on an end-effector of the robotic manipulator rigidly attached to one or more joints of the robotic manipulator; q is a vector of length n defining the pose of the robotic manipulator; {dot over (q)} is the rate of change q with time; J is a known mxc3x97n manipulator Jacobian and is possibly a function of q; NJ is an nxc3x97(nxe2x88x92m) two-dimensional array defined such that JNJ=0; xcex1 is a known scalar; W is a known two-dimensional array and is a function of q; and F is a known vector and is a function of q, and at least one or more of W, F and xcex1 are created in the memory device by the controller as part of the code tree structure. Even still further, the control system equation may also include a scaling factor xcex2(q,V) so that the values provided by the control system are given by:             q      .        =                                        β                                      (                              q                ,                V                            )                                                      [                          J                                                N                  J                  T                                                W                                      ]                                    -          1                                  [                  V                                    -              α                                                  xe2x80x83                                                  N              J              T                                    F                          ]              ,
and the scaling factor xcex2(q,V) may be created in the memory device by the controller as part of the code tree structure.
Also in case of the code structure being a code tree structure, the code tree structure may further comprise at least one container, and the container may contain the root node and may be implemented so as to be able to create the expression elements of the other branch and leaf nodes. Further, the container may provide access to information relating to the state of the control system. Further still, each expression element may provide an indication allowing access to the container.
Also in accord with the first aspect of the invention, the control system may further comprise a singularity avoidance element using multi-pass singularity detection.
Still also in accord with the first aspect of the invention, the control system may further comprise at least either means responsive to an exchangeable end-effector description or means responsive to an exchangeable joint type description.
Yet still also in accord with the first aspect of the invention, a creator function may be used by the controller to impart to the code structure executable logic.
In a second aspect of the invention, a method is provided by which a control system is operative to control a controlled element using a control system equation, the method characterized by: a step in which expressions or values for at least some components of the control system equation are communicated to the control system as a script file; and a step in which the control system creates, in a memory device from which coded instructions are then obtained by which the control system is operative, at run-time, a code structure representing each of the components of the control system equation for which the script file provides an expression or a value, wherein in creating the code structure, the control system imparts to the to code structure executable logic enabling the code structure to return a set of one or more values when queried.
Thus, the invention provides for a control system to be changed quickly, at run-time simply by downloading a new description of all or part of the control system, i.e. of some or all of the algorithms and functions that in combination make up the control system, using a hierarchical (object-based) scripting language such as XML in which the algorithms are represented by a special tree structure. Therefore, when it is decided that a new (or altered) control algorithm is to be used, the algorithm is implemented per the scripting language and so no compilation is needed. An autonomous agent (such as a robotic manipulator) using the new algorithm need only read the corresponding script in a new configuration provided via an input stream, i.e. any pathway by which data is input to the autonomous agent, including e.g. the internal pathway from a physical disk drive (in case the script/ data is a file on a disk), a physical network connection (such as Ethernet), or a wireless network connection (Such as 802.11 or Bluetooth). The software that resides on or in the autonomous agent interprets the script/data based on a language grammar.
The special tree structure provided by the invention supports rapid execution of complex algorithms yet is flexible enough to implement novel control algorithms without recompilation. The tree has a root node, and also has parent nodes and child nodes. Each parent node can have any number of child nodes, and each child node has one parent node. The tree relies on a generic core velocity-control algorithm that is made robust using filters that are elements in the control tree.
By organizing the control system in this fashionxe2x80x94i.e. so as to be updatable using a scripting language document indicating alterations to the control system based on a tree structure representation of changes to the control systemxe2x80x94dynamic programming (tabulating the solutions to subproblems) can be used for fast execution. The invention reduces the time required to calculate control values by avoiding duplication of subproblems.
The control algorithms, tree structure, and scripting language support multiple cooperating manipulators, general exchangeable end-effector descriptions, and exchangeable joint types. The tree representation also supports exchangeable, flexible end-effector descriptions.

Method and apparatus for dynamically reprogramming remote autonomous agents


A dispensing gun assembly including a gun body having a handle and a housing attached to the gun body. The housing includes first and second fluid passageways and first and second valve receiving bores. The fluid passageways are segregated from one another within the housing. First and second valves are received in the valve receiving bores. Each valve has open and closed positions and the valves move within the valve receiving bores when changing between the open and closed positions. A trigger member controllably contacts the valves and a nozzle assembly is connected to the housing.

1. Field of the Invention
The present invention relates generally to an apparatus for mixing and dispensing plural component foams, and more particularly, to a dispensing gun for mixing and dispensing a two-component urethane foam utilizing pressurized gas. Preferably, the dispensing gun is a disposable-type gun suitable for use as part of a disposable foam component kit.
2. Description of the Related Art
In recent years, improvements have been made in dispensing plural component synthetic materials, primarily foams, many of which are urethane foams or those involving similar chemistry. In such foams, an "A" or isocyanate component and a "B" or resin component are mixed in a mixing chamber adjacent the point of dispensing and the thus-formed mixture reacts in or near the dispensing nozzle. The combination of the heat from the reaction between the resin and the isocyanate components, and the reduced pressure resulting from passage outside a pressurized container causes a dissolved liquid propellant, such as a halocarbon of low boiling point, to expand and create a froth. Such expansion can also be used to create a propulsive force.
Systems of this sort have been placed in widespread use and have made it possible for a wide variety of users to derive the benefits of on-site generation and dispensing of urethane foam for purposes of insulation, flotation, void fill and the like. Further development enabled urethane foam to be mixed on-site and dispensed from kits that were light enough to be portable by users, and yet large enough to dispense significant quantities of foam. Typically, the kits that are readily portable are capable of mixing and dispensing 100-600 board feet of uniformly high quality urethane foam. Such foam usually has a finished density of 1.5 to 4.5 pounds per cubic foot ("pcf") and provides buoyancy, adhesion, structural rigidity and outstanding thermal insulation.
When the "A" and "B" components are mixed in proper proportions, they typically react quickly to form and solidify into an expanded foam. Foam dispensing guns must, therefore, be kept free from buildup of the foam components and resulting expanded foam, so that control valves and passageways do not become clogged, rendering the foam dispensing gun inoperable.
U.S. Pat. No. 5,529,245 discloses a low cost mixing and dispensing gun with a valve body containing a pair of liquid inlets, a pair of separate liquid outlets, a gas outlet and a removable mixing and dispensing nozzle. The nozzle contains the ingredients while they are being mixed and a gas outlet is positioned within the nozzle so as to propel the mixed ingredients to the application area.
There is a need for a foam dispensing gun having improved reliability and performance. It is desirable to have a foam dispensing gun with improved component mixing capabilities. It is also desirable to have these improved features in a foam dispensing gun suitable for throw-away use with a disposable portable foam component kit.

Dispensing gun assembly for mixing and dispensing plural component foam


A data processing device connects to a first display and operates in a power state including a power-off state, a recording standby state, and a power-on state. A second display displays an operation state of the data processing device. A power controller supplies electric power to a driver in the power-on state and the recording standby state, and stops supplying the electric power in the power-off state. The second display indicates that power is ON in the power-on state, and indicates that the power is OFF in the recording standby state and the power-off state. The power controller switches the power state from the recording standby state to the power-on state when a signal instructing start of a recording operation is received from the first display and the power state is the recording standby state.

Conventionally, a system has been suggested, wherein the system connects a display device (for example, a television receiver) for receiving television broadcast to display video and a data processing device capable of recording television broadcast data via a communication interface, so that the data processing device can be remotely operated by a control signal transmitted from the display device.
For example, a recording/reproducing device described in patent document 1 is connected to a television receiver including a built-in set-top box and can be remotely operated by a control signal transmitted from the television receiver including the built-in set-top box. When this recording/reproducing device receives a power-on signal transmitted from the television receiver including the built-in set-top box while the power of the recording/reproducing device is off, the recording/reproducing device is turned on. Further, when the recording/reproducing device receives a timer program recording signal, the recording/reproducing device records received television broadcast data to a recording medium therein. It should be noted that, while the recording/reproducing device is off, this recording/reproducing device does not supply electric power to an input/output unit, a signal processing unit, a recording unit, and a control unit but continues to supply electric power to a unit for detecting whether there is any control signal. When the recording/reproducing device receives the power-on signal transmitted from the television receiver including the built-in set-top box, the recording/reproducing device begins to supply electric power to the input/output unit, the signal processing unit, the recording unit, and the control unit. Not only the remote operation during power-off but also power saving are achieved by the configuration as described above.
Patent document 1 also discloses a timer recording registration method with the television receiver including the built-in set-top box. The method suggested can be applied to a case where the television receiver including the built-in set-top box transmits a recording start signal to the recording/reproducing device.
Generally, a hard disk device (hereinafter referred to as "HDD") needs to perform spin-up from the stopped state until a recordable state, and it takes time to complete spin-up. Especially, when the HDD is activated at the power-off state (a state where no electric power is supplied), it takes more time to complete the spin-up (for example about 8 to 20 minutes).    Patent Document 1: Japanese Patent Laid-Open No. 2004-349790    Patent Document 2: Japanese Patent Laid-Open No. 2006-209941

Data processing device and power control method


A semiconductor device includes a first insulating layer; a wiring layer formed on a first surface of the first insulating layer and including a first electrode pad; a semiconductor chip; a second insulating layer including a semiconductor chip accommodating portion; a third insulating layer on the second insulating layer; and a passive element including an electrode and formed of an embedded portion and a protruding portion on a second surface of the first insulating layer, wherein an end surface of the embedded portion is coated by the insulating layer, the electrode of the passive element is electrically connected to the wiring layer through a via wiring formed in the insulating layers, the first electrode pad is electrically connected to another semiconductor device through a joining portion, and a protruding amount of the protruding portion is less than a gap between the second surface and the another semiconductor device.

There is proposed a semiconductor device having a package on package structure (a so-called POP structure), where a second semiconductor device is laminated on a first semiconductor device, on which a semiconductor chip as an active element and a passive element are mounted. Such a semiconductor device has a structure where the semiconductor chip or the passive element is mounted on a surface of the first semiconductor device or on a surface of the second semiconductor device between the first semiconductor device and the second semiconductor device as disclosed in Japanese Unexamined Patent Application Publication No. 2008-153492.


Embodiments are directed to a computer-implemented method that includes receiving, at a triggering system, input data about an environment. Machine learning (ML) algorithms extract features from the input data and analyze relationships among and between the features to generate user-interaction-readiness model of person-A's readiness to participate in a human interaction with other persons in the environment. The ML algorithms to apply real-world data about person-A to the user-interaction-readiness model to generate a first classification output comprising data representing person-A's readiness to participate in a human interaction with other persons in the environment. Based at least in part on a determination that person-A and another person(s) in the environment are interaction candidates, the triggering system triggers the initiation of human interaction strategies configured to facilitate human interactions between person-A and the previously identified another person(s) in the environment.

The present invention relates in general to computing devices. More specifically, the present invention relates to computing systems, computer-implemented methods, and computer program products that cognitively trigger computer-implemented human interaction strategies to facilitate collaboration, productivity, and learning.
A dialogue system or conversational agent (CA) is a computer system configured to communicate with a human using a coherent structure. Dialogue systems can employ a variety of communication mechanisms, including, for example, text, speech, graphics, haptics, gestures, and the like for communication on both the input and output channels. Dialogue systems can employ various forms of natural language processing (NLP), which is a field of computer science, artificial intelligence, and computational linguistics concerned with the interactions between computers and humans using language. Among the challenges in implementing NLP systems is enabling computers to derive meaning from NL inputs, as well as the effective and efficient generation of NL outputs.

Cognitive triggering of human interaction strategies to facilitate collaboration, productivity, and learning

INTERNATIONAL BUSINESS MACHINES CORPORATION


A safety gate has a frame with spaced apart top and bottom assemblies and spaced apart side assemblies in a deployed configuration. The top and bottom assembly length is extendable and retractable between the opposed side assemblies. A flexible barrier is connected to the frame. A one-way jack mechanism can be carried on each of the top and bottom assemblies. The length of the assemblies can be extended without actuating the jack mechanisms to adjust the frame to nearly fit a space between two surfaces. The jack mechanisms, when actuated, incrementally further extend the top and bottom assemblies so the frame interferingly fits between the two surfaces under compression. The frame can be reconfigurable between a compact configuration and the deployed configuration. The side assemblies can include latches that lock the frame in the deployed configuration.

1. Field of the Disclosure
The present disclosure is generally directed to safety gates and, more particularly, to a safety gate with a clamp adjustment mechanism for extending the length or width of the safety gate and securely installing the safety gate in an opening.
2. Description of Related Art
Safety gates for preventing children and pets from accessing specific areas in a home or dwelling, such as a stairwell or a particular doorway, are well known in the art. Conventional safety gates, such as the one disclosed in expired U.S. Pat. No. 4,492,263, generally have overlapping panels and tubes that are widthwise slidably adjustable to extend the width of a particular opening. The tubes or panels have end caps or feet that engage the surfaces of the opening or doorway when the gate is installed. The end caps or feet are typically installed under compression between the surfaces of the doorway or opening to secure the safety gate in place.
Conventional safety gates tend to be rather bulky and have a rudimentary adjustment system with relatively large adjustment increments. As a result, safety gates can be difficult to transport and/or store and can be time consuming and frustrating to set-up. Such safety gates can also be difficult to adjust to precisely fit a given opening. Often, the gate can be adjusted incrementally to fit different opening sizes. However, the adjustment sizes can be limited by the relatively large gap between available size increments. The actual opening size to be barricaded often falls between two adjustment increments. Thus, the gate may be under too much, which may damage the surfaces of the opening, or under too little compression and thus not fully secured in place when installed.
Clamp mechanisms are also well known in the art. Conventional clamp mechanisms, such as the one disclosed in expired U.S. Pat. No. 5,009,134, generally include a fixed jaw and a movable jaw. When the clamp mechanism is actuated, the movable jaw moves towards the fixed jaw to clamp an item between the jaws. A squeezing action on a grip, handle, or actuator is typically employed to allow for small incremental adjustment of the clamp jaw spacing relative to one another.


Aspects of the invention can provide an alignment method that is preferably applicable when manufacturing equipments by liquid-phase processing. The alignment method in a device manufacturing process can include forming of a functional film on a substrate by liquid-phase processing, forming an alignment mark on the substrate on which the functional film is formed so as to make a pattern of the alignment mark appear on a film that is formed after forming the functional film, and aligning the film that is formed after forming the functional film by using the alignment mark.

1. Technical Field of Invention
Aspects of the invention can relate to an alignment method, a method for manufacturing a semiconductor device, a substrate for a semiconductor device, and electronic equipment.
2. Description of Related Art
Related art methods for manufacturing a thin-film electronic device have been developed based on vacuum processing employing evaporation. While the vacuum processing can provide extremely high processing accuracy, it consumes a significant amount of energy and materials ineffectively. Therefore, low energy consuming, liquid-phase processing (using a liquid-phase method) has come under review as a substitution for the vacuum processing. See, for example, Domestic Republication of PCT International Publication No. WO 00/59040.
The liquid-phase processing provides the following advantages over the related art vacuum processing that involves evaporation. First, no vacuum equipment is required, which makes it possible to reduce the size of a manufacturing equipment. Second, the surface of films are planarized, which prevents the breaking of wires provided on the surface. Also, a high-voltage-resistant transistor can be manufactured by using a planarized film as a gate insulating film.

Alignment method, method for manufacturing a semiconductor device, substrate for a semiconductor device, electronic equipment


Each control period includes a right eye display period and a left eye display period. A driving circuit supplies grayscale potential based on a right eye image to each pixel in each of the three unit periods of the right eye display period, and supplies the grayscale potential based on a left eye image to each pixel in each of the three unit periods of the left eye display period. The driving circuit performs overdriving in two unit periods from the beginning of each display period, sets the polarity of a voltage applied to each pixel in the two unit periods from the beginning of each display period reverse in the right eye display period of the control period and in the right eye display period of the control period.

1. Technical Field
The present invention relates to a technology which displays a right eye image and a left eye image to which parallax is mutually applied such that an observer perceives a stereoscopic effect.
2. Related Art
A stereoscopic method using a frame sequential method of alternately displaying a right eye image and a left eye image in a time division manner has been proposed from the related art. In a period during which one of the right eye image and the left eye image is changed to the other, the right eye image and the left eye image are mixed, so that it is difficult for an observer to recognize a definite stereoscopic effect when the observer views the image (crosstalk). In order to solve the above-described problem, for example, JP-A-2009-25436 discloses a technology for causing both the right eye shutter and the left eye shutter of stereoscopic eyeglasses to be in a closed state so that an observer does not view an image in the period during which one of the right eye image and the left eye image is changed to the other (that is, in the period during which the right eye image and the left eye image are mixed).
As shown in FIG. 11, the display period PR of the right eye image and the display period PL of the left eye image are alternately set. Each display period P (PR, PL) is divided into a unit period U1 and a unit period U2. The display image is changed from the left eye image to the right eye image in the unit period U1 of the display period PR and the right eye image is displayed in the unit period U2 which is immediately after the unit period U1, so that the display image is changed from the right eye image to the left eye image in the unit period U1 of the display period PL, and the left eye image is displayed in the unit period U2 which is immediately after the unit period U1. In the unit period U1 of each display period P, control is performed such that both the right eye shutter and the left eye shutter are in the closed state. Accordingly, the mixture of the right eye image and the left eye image is not perceived by the observer.
However, in the foundation of the technology disclosed in JP-A-2009-25436, control is performed such that a period during which the observer can actually view an image is about the half (unit period U2) of each display period P. Accordingly, there is a problem in that it is difficult to sufficiently secure the brightness of a display image.

Electro-optic apparatus and electronic apparatus


A self-routing packet switching network architecture receives parallel incoming data packets and divides each of the corresponding bits within each data packet into words. The words are distributed into multiple transport channels, one word being placed into each channel in an alternating fashion. The words are transported through the channels and later words are input to the channels. Header words are also input to a self-routing network circuit. The self-routing network circuit determines the switching decisions to be made at each stage of a routing segment in order to properly route the words. Routing segments at the ends of the transport channels route the data according to these switching decisions. The use of multiple transport channels allows the network to operate internally at a reduced clock rate while still maintaining the same bandwidth as a direct bridge network architecture.

Packet switching networks are frequently relied on to direct information to specific destinations at high speeds. Such networks are frequently used in digital communications systems, such as telephone switching networks, and in parallel processing applications to communicate between processors.
A self-routing packet switching network is a packet switching network in which switch nodes within the network set themselves based on information contained in the incoming data. Referring to FIG. 1, a typical self-routing packet switching network is designated generally at 10. Incoming packets 12 comprise a header segment 14, which contains the intended destination of the packet 12, and a data segment 16 containing the data to be routed. The first bit of the header segment 14 is an activity bit which tells whether or not the packet is active. Each packet 12 is a serial stream of bits and each packet has the same length.
As shown in FIG. 1, the self-routing packet switching network 10 receives m packets concurrently 3, the packets concurrently entering the network 10 as parallel streams of sequential bits. The network 10 reads the header bits of the header segment 14 of each packet and routes the packet to the output line specified by those bits. Routing in this context is typically defined to include two functions, sorting and expanding. A typical self-routing packet switching network, such as the one shown in FIG. 1, includes both a sorting network 18 and an expanding network 20 to accomplish routing. The sorting network 18 simply orders the packets relative to one another based on the information in the header segment 14 of each packet 12. The expanding network 20 routes sorted packets to an actual physical destination. If some destinations are unused, the expanding network 20 routes the sorted packets around these unused destinations. Destination "2" in FIG. 1, designated at 24, is an example of an unused destination which the expanding network 20 routes packets around.
All self-routing packet switching networks make use of some self-routing algorithm to accomplish the sorting and expanding functions. A self-routing algorithm involves a series of comparisons of incoming bits, after which, if necessary, data lines are interchanged. Referring now to FIG. 2, a simple example of the way a sorting algorithm works is demonstrated by a network 30. The network 30 sorts header data on four input lines 34 into descending order (top to bottom) with six switching elements 41, 42, 43, 44, 45 and 46. A switching element that is schematically represented by an upward arrow within a circle indicates that the data on the two adjacent lines is switched if the data on the bottom line is larger than the data on the top line. Thus, such a switching element ensures that, after the switching element, the top line will contain data that is larger than the data on the bottom line. Conversely, a switching element that is schematically represented by an downward arrow within a circle indicates that the data on the two adjacent lines is switched if the data on the top line is larger than the data on the bottom line. Thus, such a switching element ensures that, after the switching element, the bottom line will contain data that is larger than the data on the top line.
In FIG. 2, exemplary inputs to the network 30, from top to bottom, are 2-1-4-3. A stage in a self-routing packet switching network comprises a vertical column of switching elements. The switching elements 41 and 42 comprise the first stage 51 of the network 30. The switching element 41 allows the data to pass through the adjacent lines without switching because the larger number is already on the top line. The switching element 42, however, interchanges the 4 and the 3 so that the larger data, the 4, is on the bottom line. The middle two inputs cross before a second stage 52, which compares the 2 and 3 (interchanging them), and the 1 and 4 (also interchanging them). This process is repeated at the final stage 53 so that the sorted output is 4-3-2-1.
A frequently used self-routing algorithm is known as the Batcher-Banyan algorithm. In a Batcher-Banyan sorting network handling n concurrent incoming packets, there are (log.sub.2 n)(log.sub.2 n+1)/2 stages of switching elements.
An expanding network is also a complex series of comparisons and interchanges, similar to that of a sorting network. Together, the sorting and expanding networks make up the routing network, also known as the "fabric network." Many different algorithms have been used to make routing decisions, and all are well known to a person having ordinary skill in the art. Any of these algorithms, when implemented, produces a "fabric" of interconnections and ultimately result in the same output. Thus, although some algorithms may be more efficient than others, any fabric implementation of a self-routing algorithm can be used in a self-routing packet switching network.
Most self-routing packet switching networks use the self-routing fabric as a direct bridge between the incoming data and the routed output. A typical direct bridge configuration is shown in FIG. 3. In a direct bridge configuration, incoming data packets 60 are clocked directly through the self-routing fabric 62, comprised of a sorting network 64 and an expanding network 66. All of the data passes through the self-routing fabric 62, each bit of each packet one stage ahead of the following bit.
The direct bridge configuration presents problems in applications handling rapidly arriving data packets. The configuration requires that the switching in the self-routing fabric be done at the same clock speed as the input and the output to the network. Every switching element in the self-routing fabric must operate at this high clock rate. As the target input-output clock frequency of the network approaches the maximum speed of the technology utilized (such as CMOS, ECL, or GaAs), the manufacturing yield for the network is reduced. For any given single-chip network, it becomes increasingly unlikely that every switching element on the chip will be able to operate at the required speed. An exemplary network handling 32 concurrent packets with an 80 Gb/s bandwidth (the bandwidth of a network is the total number of bits per second entering and leaving the network) would have to operate at 2.5 GHz. The number of transistors required would only be on the order of 70,000, but there would be no time margins for these transistors. Thus, an unacceptably poor yield would be expected.
Another exemplary network can achieve the same 80 Gb/s bandwidth by using a slower 625 MHz clock and increasing the number of concurrent packets to 128. However, as the number of concurrent packets being routed increases, the quantity of switching elements required in the self-routing fabric increases rapidly. Thus, the use of 128 concurrent packets requires on the order of 400,000 transistors. Although there are no timing problems with such an architecture, this type of architecture requires an enormous number of transistors and is very costly.
The direct-bridge architecture presents the classic size versus speed trade-off. In high-speed applications, maximizing bandwidth is essential. However, conventional architecture, using a self-routing fabric network as a direct bridge between the input and output of the network, requires either vast numbers of transistors operating at reasonable speeds, or a more reasonable number of transistors straining to operate at high clock speeds. This latter method has the problem of unreasonably low manufacturing yields, due to the fact that the technology used limits the maximum clock rate that can be used.
Thus, there is a need for an architecture of a self-routing packet switching network that can operate internally at a clock speed lower than that of the network input and output, while at the same time not comprising a large additional number of transistors, while maintaining a high bandwidth.

Multichannel self-routing packet switching network architecture


The specification and drawings present a new method and a system for organizing and structuring a process of tool manufacturing with a reduced lead time. The manufacturing of the component tooling can be applied (but not be limited) to: mold tooling, injection mold tooling, diecast tooling, press tooling, etc. Several techniques or elements are methodically combined with the focus to reduce overall manufacturing time for tooling components comprising (but not be limited to) the following: a) standard parts are designed, pre-manufactured and stocked in a pre-hardened condition; b) custom 3D CAD libraries are created which represent the standard parts and only allow a tool designer to select standard parts which are held as a pre-manufactured stock; c) manufacturing fixtures are utilized which allow consistent and rapid setup of the pre-manufactured standard components for customized machining operations specific to a tool design.

The manufacturing lead-time for injection mold tools is typically 3 to 8 weeks in the telecom industry. The process of manufacturing an injection mold tool is complex and involves many steps, the main ones being:                Component CAD (computer aided design) file import and adjustment/correction;        Mold tool design;        Creation of numerical control programs for CNC (computer numerical control) machine tools;        Rough machining of tool components;        Hardening of tool components;        Finish machining of tool components;        Machining of electrodes for electro discharge machining (EDM);        EDM of tool components; and        Tool assembly.
One of the issues in the manufacture of tooling is the setup of the tool room logistics to minimize the manufacturing lead-time. In consumer product industries where time to market is critical, tooling lead-time is often an important factor for product development.
Furthermore, there are several relevant areas which include (but are not limited to):                Pre-manufactured components. In the mold tool industry there exists standard part suppliers such as STRACK and HASCO. These companies provide catalogue items which are fully finished or can have additional features machined in them by the toolmaker.        Machining of hardened steels. During recent years, machine tool cutter technology and machining operations (such as high speed milling) have developed to a state where it is acceptable as a standard process to machine pre-hardened steel. Historically this was a non preferred manufacturing process because of cutter wear problems and low metal removal rates; typically, hardened steels would have been ground or machined by one of the electro discharge techniques.        CAD libraries. For several years, a feature of Computer Aided Design (CAD) software systems is an ability to create custom libraries of component models. Many CAD systems (e.g., CATIA, UGS, PRO ENGINEER, AUTOCAD) can provide CAD libraries for commercially available catalogue components from suppliers such as STRACK and HASCO. The component suppliers themselves will often provide the libraries as a marketing support for their products.        Customized manufacturing fixtures. To accurately machine a piece of metal, the starting component has to be held firmly in a known location within the cutting zone of the machine tool. This normally involves fixing the component to the machine tool table by clamping the component in a vice or using some form of a magnetic holding device. Once held, the exact location of the component has to be measured to allow offset/adjustment of the programmed cutter path. Where more than one component or a number of similar components are to be machined in the same or similar processes, then a specific support fixture is usually made. This allows easier location and retention of components to be machined in the same orientation/position.

Lead time reduction for manufacturing of tooling


A method and apparatus for maintaining the cells of a fuel cell stack are disclosed. The apparatus includes a fuel cell maintenance device including means for imposing a low impedance across at least one cell of a fuel cell stack, e.g., a switch, and a pulse generator. The pulse generator is capable of pulsing a cathode of the at least one cell of through the low impedance imposing means, e.g., when the switch is closed. The method transparently maintains the cells of a fuel cell stack, and includes sequentially pulsing the cathodes of a plurality of cells in a fuel cell stack, and maintaining a consistent number of the cells providing power to a load of the fuel cell stack while sequentially pulsing the cathodes of the cell.

1. Field of the Invention
The present invention pertains to fuel cells, and, more particularly, to a cell maintenance device for fuel cell stacks.
2. Description of the Related Art
Fuel cell technology is an alternative energy source for more conventional energy sources employing the combustion of fossil fuels. A fuel cell typically produces electricity, water, and heat from a fuel and oxygen. More particularly, fuel cells provide electricity from chemical oxidation-reduction reactions and possess significant advantages over other forms of power generation in terms of cleanliness and efficiency. Typically, fuel cells employ hydrogen as the fuel and oxygen as the oxidizing agent. The power generation is proportional to the consumption rate of the reactants.
A significant disadvantage which inhibits the wider use of fuel cells is the lack of a widespread hydrogen infrastructure. Hydrogen has a relatively low volumetric energy density and is more difficult to store and transport than the hydrocarbon fuels currently used in most power generation systems. One way to overcome this difficulty is the use of "fuel processors" or "reformers" to convert the hydrocarbons to a hydrogen rich gas stream, which can be used as a feed for fuel cells. Hydrocarbon-based fuels, such as natural gas, LPG, gasoline, and diesel, require conversion for use as fuel for most fuel cells. Current art uses multi-step processes combining an initial conversion process with several clean-up processes. The initial process is most often steam reforming ("SR"), autothermal reforming ("ATR"), catalytic partial oxidation ("CPOX"), or non-catalytic partial oxidation ("POX"). The clean-up processes are usually comprised of a combination of desulphurization, high temperature water-gas shift, low temperature water-gas shift, selective CO oxidation, or selective CO methanation. Alternative processes include hydrogen selective membrane reactors and filters.
Thus, many types of fuels can be used; some of them hybrids with fossil fuels, but the ideal fuel is hydrogen. If the fuel is, for instance, hydrogen, then the combustion is very clean and, as a practical matter, only the water is left after the dissipation and/or consumption of the heat and the consumption of the electricity. Most readily available fuels (e.g., natural gas, propane and gasoline) and even the less common ones (e.g., methanol and ethanol) include hydrogen in their molecular structure. Some fuel cell implementations therefore employ a "fuel processor" that processes a particular fuel to produce a relatively pure hydrogen stream used to fuel the fuel cell.
One problem arising in proton exchange membrane ("PEM") fuel cells used with fuel processors is the formation of hydrogen peroxide on the platinum catalyst of precious metals catalyzed reactors. One mode of decay in PEM fuel cells is due to the formation of hydrogen peroxide at the anode of the fuel cell. The hydrogen peroxide currently limits PEM fuel cell life. This mechanism was first elucidated by A. B. LaConti in the 1960's. See "Mechanisms of membrane degradation (polymer electrolyte membrane fuel cells and systems, PEMFC)", A. B. LaConti, M. Hamdan, and R. C. McDonald, Handbook of Fuel Cells; Vol. 3, Ch 49, pp 647-662, Edited by W. Vielstich, A. Lamm, and H. Gasteiger, Wiley, Chichester UK, 2003. Hydrogen peroxide is a strong oxidant that attacks the fuel cell membrane. It is generally formed by oxygen diffusing from the fuel cell cathode to the anode. The graph in FIG. 1 shows that even with very low oxygen partial pressure, the peroxide partial pressure can be quite high at anode potentials (˜0.0 volts). It is apparent from FIG. 1 that, if the anode potential is raised 200 millivolts, the peroxide concentration drops by three orders of magnitude.
More particularly, platinum oxide is a relatively inactive catalyst for oxygen reduction. Platinum forms a hydrated oxide Pt(OH)2 according to the equilibrium relation:
The equilibrium potential for forming the hydrated oxide is given by:Eo=0.98−0.0591 pHAtlas of Electrochemical Equilibria in Aqueous Solutions (2nd ed), M. J. N. Pourbaix, NACE, Houston, Tex. 1974, page 379 ("Pourbaix"). Pourbaix also shows how higher oxides may form. In addition, Pourbaix shows a complex relationship between Pt, PtO, PtO2 and Pt2+ ion.
The result of these reactions and relations are shown in FIG. 2, which is modified from Pourbaix. FIG. 2 shows the domains of immunity where Pt does not corrode and the domain of passivation where Pt corrodes to a stable hydrated oxide. The oxides are not especially catalytic for oxygen reduction. An inspection of FIG. 2 shows that dropping the cathode potential below the solid line 200, will make the platinum oxide unstable, and make the metal stable. If the cathode potential is allowed to move above the line 200, the oxide will be stable and the metal will be unstable. The process is also complex because the local pH has an effect on the process as well. Increasing the pH, as might occur under high current conditions (e.g., from cathodic proton consumption), will favor the formation of the oxide at lower cathode potentials.
These and other, similar problems have been known for more than 40 years. During this time, the art has sought to find a technically feasible, economically viable solution to these challenges. The problem is exacerbated by competition from alternative technologies, which are already capable generating and providing power at extremely low costs, due in part to an already installed infrastructure. Several approaches have been proposed, but none have found commercial acceptance.
The present invention is directed to resolving, or at least reducing, one or all of the problems mentioned above.

Cell maintenance device for fuel cell stacks