A volatile component is recovered from an inert gas blanketed gas source containing the volatile component, an inert carrier gas, water vapor and oxygen as an impurity by a continuous process including the steps of adsorbing the water vapor from the stream, condensing substantially all of the volatile component from the stream, heating the water vapor-free and volatile component-free gas stream, purging the adsorbers with the heated gas stream and venting the purge gas and desorbed moisture. Inert gas depleted from the source is replenished with oxygen-free inert gas, thereby minimizing the concentration of oxygen in the source.

This invention relates to the recovery of high boiling gaseous compounds such as vaporized, normally liquid compounds, from gaseous mixtures, and more particularly to the recovery of vaporized solvents from solvent-inert carrier gas mixtures by condensing the solvent from the gas mixture.
Many technical and industrial processes result in the production of a product or by-product gas stream that contains a vaporized, normally liquid compound, i.e. a compound that is liquid at normal temperatures and pressures. For example, in the curing of organic solvent-borne resin coatings that have been deposited onto surfaces or articles, e.g. painted or lacquered metal parts for automobiles, home appliances and the like, it is common to bake the resin coating in an oven, thereby evaporating the solvent contained in the coating mixture and curing the solvent-free resin coating material. During the drying process the vaporized solvent is generally removed from the drying oven by a carrier gas that is inert with respect to the vaporized solvent under conditions that prevent or minimize the possibility of formation of an explosive or flammable gas mixture.
There is often a need to recover the high boiling gas component from the above-described gas mixtures. For instance, in some cases, the high boiling gas may have economic value that makes its recovery very desirable. In other cases, the high boiling gas may be hazardous or harmful to the environment and thus cannot be released to the atmosphere. Various methods have been employed for effecting the recovery of high boiling gas components from gas mixtures. Typical methods include condensation, adsorption and membrane separation. Condensation is often preferred because of its simplicity and efficiency.
Separation by condensation involves cooling the high boiling gas-laden gaseous stream to a temperature well below its dew point, thereby causing the high boiling gas to condense to the liquid state. The liquefied gas is then removed from the system. Processes for condensing high boiling gases from gas streams are disclosed in U.S. Pat. Nos. 4,122,684, 4,188,793, 4,237,700, 4,444,016, and 4,545,134.
Condensation works well for the recovery of high boiling gaseous compounds. Gas mixtures containing these compounds can be cooled to a temperature low enough to remove sufficient high boiling gas from the stream to enable the lean gas stream to meet the strict environmental standards set for gases discharged to the atmosphere without freezing the high boiling gas component on the surfaces of the condenser in which the gas mixture is cooled. However, when the gas stream contains contaminants which freeze at or above the temperature at which the heat exchange equipment must be operated, such as water vapor and/or carbon dioxide, it is difficult to successfully use a single condenser to condense the high boiling gas, since the condenser will eventually clog up with the frozen contaminant and have to be taken out of service until the frozen contaminant is removed from the condenser.
U.S. Pat. No. 4,188,793, issued to Watson et al. discloses the removal of impurities such as water and carbon dioxide from a gas mixture from which vinyl chloride is also to be separated by passing the incoming gas mixture through heat exchangers in which the impurities are frozen. Reversing heat exchangers can be employed in alternate service, so that while the contaminant is being frozen in one heat exchanger, the frozen contaminant is being thawed in the other heat exchanger. This patent also discloses removing vinyl chloride from the dried gas stream by condensation using liquefied nitrogen as the refrigerant. The nitrogen, which is vaporized and warmed during the condensation step is subsequently used to thaw the frozen impurities.
It is also known to pass the gas stream through adsorbers to remove moisture and other condensable contaminants from the gas stream prior to introducing the gas stream into a solvent condenser. The adsorbers are conventionally regenerated by passing a heated gas obtained from an external source, such as dry nitrogen or air, through the adsorbers. The solvent-depleted gaseous effluent from the condenser is usually recycled to the source of the gas stream for reuse as an inerting and carrier gas. When the gas stream contains a noncondensable impurity, such as oxygen or carbon monoxide, which enters the system as a result of leakage or chemical reaction, there is a likelihood of undesirable build-up of the impurity in the gas stream. Accordingly, it is not always practical to reuse the condenser effluent as a carrier gas, and fresh inert carrier gas must be used. This reduces the operating efficeincy of the recovery system.
There is a continuing search for improved systems for the recovery of high boiling gases from gas streams that additionally contain non-condensable gaseous impurities, the build-up of which cannot be tolerated in the system being treated. In particular, it is desirable to develop improvements to such systems that will enable them to operate more efficiently and effectively and at lower costs. The present invention provides improvements which produce these benefits.

Adsorption condensation solvent recovery system


An electrochemical cell system is disclosed, wherein at least one electrochemical cell is provided in a vessel. The electrochemical cells each include a membrane electrode assembly having a first electrode, a second electrode, and a membrane disposed between and in intimate contact with the first electrode and the second electrode. The vessel is disposed around the membrane electrode assembly. The vessel defines at least a portion of a first storage area that is in fluid communication with the first electrode. Further vessel defines at least a portion of a second storage area that is in fluid communication with the second electrode.

The present disclosure relates to an electrochemical cell system, and especially relates to the use internal reactant and fluid storage areas in a fully integrated electrochemical cell.
Electrochemical cells are energy conversion devices, usually classified as either electrolysis cells or fuel cells. An electrolysis cell functions as a hydrogen generator by electrolytically decomposing water to produce hydrogen and oxygen gases, and functions as a fuel cell by electrochemically reacting hydrogen with oxygen to generate electricity.
Referring to FIG. 1, a partial section of a typical proton exchange membrane fuel cell 10 is detailed. In fuel cell 10, hydrogen gas 12 and reactant water 14 are introduced to a hydrogen electrode (anode) 16, while oxygen gas 18 is introduced to an oxygen electrode (cathode) 20. The hydrogen gas 12 for fuel cell operation can originate from a pure hydrogen source, methanol or other hydrogen source. Hydrogen gas electrochemically reacts at anode 16 to produce hydrogen ions (protons) and electrons, wherein the electrons flow of from anode 16 through an electrically connected external load 21, and the protons migrate through a membrane 22 to cathode 20. At cathode 20, the protons and electrons react with the oxygen gas to form resultant water 14xe2x80x2, which additionally includes any reactant water 14 dragged through membrane 22 to cathode 20. The electrical potential across anode 16 and cathode 20 can be exploited to power an external load.
The same configuration as is depicted in FIG. 1 for a fuel cell is conventionally employed for electrolysis cells. In a typical anode feed water electrolysis cell (not shown), process water is fed into a cell on the side of theoxygen electrode (in an electrolytic cell, the anode) to form oxygen gas, electrons, and protons. The electrolytic reaction is facilitated by the positive terminal of a power source electrically connected to the anode and the negative terminal of the power source connected to a hydrogen electrode (in an electrolytic cell, the cathode). The oxygen gas and a portion of the process water exit the cell, while protons and water migrate across the proton exchange membrane to the cathode where hydrogen gas is formed. In a cathode feed electrolysis cell (not shown), process water is fed on the hydrogen electrode, and a portion of the water migrates from the cathode across the membrane to the anode where protons and oxygen gas are formed. A portion of the process water exits the cell at the cathode side without passing through the membrane. The protons migrate across the membrane to the cathode where hydrogen gas is formed.
The typical electrochemical cell system includes a number of individual cells arranged in a stack, with the working fluid directed through the cells via input and output conduits formed within the stack structure. The cells within the stack are sequentially arranged, each including a cathode, a proton exchange membrane, and an anode. In certain conventional arrangements, the anode, cathode, or both are gas diffusion electrodes that facilitate gas diffusion to the membrane. Each cathode/membrane/anode assembly (hereinafter xe2x80x9cmembrane electrode assemblyxe2x80x9d, or xe2x80x9cMEAxe2x80x9d) is typically supported on both sides by flow fields comprising screen packs or bipolar plates. Such flow fields facilitate fluid movement and membrane hydration and provide mechanical support for the MEA. Since a differential pressure often exists in the cells, compression pads or other compression means are often employed to maintain uniform compression in the cell active area, i.e., the electrodes, thereby maintaining intimate contact between flow fields and cell electrodes over long time periods.
Pumps are used to move the reactants and products to and from the electrochemical cell, which is connected to the liquid and gas storage devices by a system of pipes. This use of external pumps and storage areas both limits the ease with which electrochemical cells may be transported, and complicates the use of electrochemical cells in locations where pumps and storage tanks are difficult to introduce or operate.
While existing electrochemical cell systems are suitable for their intended purposes, there still remains a need for improvements, particularly regarding operation of electrochemical cell systems with minimal reliance on external pumps and storage units.
The above-described drawbacks and disadvantages are alleviated by an electrochemical cell system comprising at least one electrochemical cell provided in a vessel. The electrochemical cells each include a membrane electrode assembly having a first electrode, a second electrode, and a membrane disposed between and in intimate contact with the first electrode and the second electrode. The vessel is disposed around the membrane electrode assembly. The vessel defines at least a portion of a first storage area that is in fluid communication with the first electrode. Further vessel defines at least a portion of a second storage area that is in fluid communication with the second electrode.


An antenna pointing detection system for use with circularly polarized electromagnetic radiation has a horn, a waveguide and at least one mode switching arm. The horn receives radiation in a primary mode from the radiation source. The waveguide receives radiation from the horn and supports only radiation in a primary mode, e.g. the TE.sub.11 mode and the next higher order TE mode, e.g. the TE.sub.21 mode at one or more rectangular mode switching arms extending from the circular waveguide for stimulating radiation of the-next order TE.sub.21 mode in the waveguide. The arm has a series of switchable pin diodes for changing the effective length of the mode switching arm to cause a phase alteration in the TE.sub.21 mode thereby causing a deflection of the effective pointing direction of the horn. The magnitude of the received signal is detected and compared with different deflections of the horn to operate conventional antenna pointing hardware.

In many applications, especially satellite communications, it is important to maximize the strength of signals received, for example, by a microwave antenna feed horn. This requires that the antenna be pointed precisely at the incoming beam even though the transmitter may not be stationary. An electronic autotracking antenna provides for autotracking on a received signal, that is, it can be used to develop signals indicating whether or not the antenna's boresight axis is aligned with the direction of the incoming signal wave front beam. To perform this function, the antenna feed is electronically switched to sequentially provide four slightly different beam receiving positions. The direction of arrival of the received signal can be deduced from the relative signal strengths in the four beam directions. This type of action is often called "sequential lobing".
The switching is typically done at a rate of less than 400 Hz which is slow relative to the signal frequencies but fast enough to allow for effectively constant correction of the antenna position. Such a system using two mode switching arms for the TE.sub.21 mode and two mode switching arms for the TM.sub.01 mode to "squint" the antenna in four orthogonal directions is well known. Such prior systems require a significant amount of hardware not otherwise required for the data transmission, limit the bandwidth capacity of the antenna and are effective only for one sense of circularly polarized signals.


A circuit breaker having a housing, fixed and movable contacts respectively supported by a fixed contact support structure and a movable contact arm, a trip mechanism, and an operating mechanism which is releasably engageable with the trip mechanism. The operating mechanism includes a pivotable operating member and a tension spring. The fixed contact support structure includes a contact supporting leg portion. The movable contact arm has a contact supporting side, and an opposite spring supporting side. The tension spring links the pivotable operating member and the spring supporting side of the movable contact arm. The contact supporting leg portion of the fixed contact support structure and the movable contact arm are disposed in closely spaced relation when the fixed and movable contacts are in engagement, to provide a reverse current loop which magnetically assists in rapid contact separation.

Miniature molded case circuit breakers, such as the miniature circuit breaker shown in U.S. Pat. No. 4,266,210, which is assigned to the same assignee as the present application, have a size limitation imposed upon them in order to fit the circuit breakers into panel boards of residential, office and light industrial applications. While the outer dimensions of a miniature circuit breaker are fixed, short circuit current magnitudes available from electrical utilities have increased, requiring the designers of miniature circuit breakers to seek new and improved operating and trip mechanisms which limit the energy let-through expressed by equation I.sup.2 t, where "I" is the current and "t" is the time from the onset of an overload to arc extinction. To limit energy let-through to an acceptable value, the circuit breaker must provide current limiting, which reduces the "I", and the time from the onset of an overload to arc extinction must be minimized. Thus, the circuit breaker must be extremely fast acting and capable of early contact separation upon the detection of an overload, and an arc voltage must be developed during contact opening which exceeds the driving voltage, to oppose the rise in short circuit current magnitude. In the limited volume available in the cavity of the molded casing, it is difficult to obtain a large contact opening distance, which thus limits the arc voltage obtainable, and it is difficult to obtain a substantial movement of the resulting arc, which is necessary to cool and quickly quench the arc without damage to the components of the circuit breaker. The limited volume available also results in a rapid increase in pressure inside the molded casing during arc interruption. While some pressure build up is beneficial in aiding arc interruption, the maximum pressure must be limited below the point which may damage the circuit breaker. Thus, it would be desirable, and it is an object of the invention, to (1) increase the contact separation distance, (2) increase arc movement, and (3) increase contact opening velocity, to provide a miniature circuit breaker having a significantly increased interruption rating. In addition, the operating mechanism of the circuit breaker must cause the actuating handle of the circuit breaker to remain in the "trip" position, once the movable contact arm crosses a toggle point.


In combination, a two-way postal card and cover envelope having the ability to be mailed out and then re-folded to use said cover and envelope again wherein the positioning of the enclosed message card will automatically completely re-address said postal card so to be re-mailed again when stapled together.

1. Field of the Invention
This invention relates to the common postal card that is used to send a message by mail and more particularly it refers to a two-way postal card wherein the message card is first used to mail out and then the card and cover envelope is re-positioned and automatically re-addressed to be returned to the original sender.
Postal cards have been known for years but the construction of a two-way postal card and envelope wherein the re-folding of the card and envelope will automatically re-address said and make ready for re-mail by simply re-positioning said message card and cover envelope is Novel.
The postal card and envelope is designed for bulk type mail that is sent out and a reply is requested. The cover envelope and message card is preferably constructed from durable paper or the like.
2. Brief Summary of the Invention
It is therefore a primary object of this invention to provide an improved two-way postal card and envelope that can be mailed out and then returned to the original sender.
It is another object to provide a two-way card that can be sealed or stapled together and after being closed the addressee can be written thereupon.
To construct a two-way postal card and cover envelope, that when received from the first party, the second party can re-position or re-fold the message card and envelope wherein said will automatically completely re-address said cover envelope and message card to be re-mailed to the original sender.


An immersive video system for displays a view window of an environment using multiple video streams. The immersive video system includes a video source containing multiple overlapping video streams. An immersive video decoder selects an active video stream based on the location of the view window. A video decoder decodes the active video stream for the immersive video decoder. The immersive video decoder then selects the appropriate parts of the video stream to display in the view window.

The present invention relates environment display systems. More specifically, the present invention relates to using multiple video streams to increase the resolution of an immersive video systems.
As the processing power of microprocessors and the quality of graphics systems have increased, environment mapping systems have become feasible on consumer electronic systems. Environment mapping systems use computer graphics to display the surroundings or environment of a theoretical viewer. Ideally, a user of the environment mapping system can view the environment at any horizontal or vertical angle. FIG. 1 illustrates the construct used in conventional environment mapping systems. A viewer 105 (represented by an angle with a curve across the angle) is centered at the origin of a three dimensional space having X, Y, and Z coordinates. The environment of viewer 105 (i.e., what the viewer can see) is ideally represented by a sphere 110, which surrounds viewer 105. Generally, for ease of calculation, sphere 110 is defined with a radius of 1 and is centered at the origin of the three dimensional space. More specifically, the environment of viewer 105 is captured and then re-projected onto the inner surface of sphere 110. Viewer 105 has a view window 130 which defines the amount of sphere 110 viewer 105 can see at any given moment. View window 130 is typically displayed on a display unit for the user of the environment mapping system.
Conventional environment mapping systems include an environment capture system and an environment display system. The environment capture system creates an environment map which contains the necessary data to recreate the environment of viewer 105. The environment display system displays portions of the environment in view window 130 based on the field of view of the user of the environment display system. An environment display system is described in detail by Hashimoto et al., in co-pending U.S. patent application Ser. No. 09/505.442, entitled xe2x80x9cENVIRONMENT DISPLAY USING TEXTURE PROJECTIONS WITH POLYGONAL CURVED SURFACES.xe2x80x9d Typically, the environment capture system includes a camera system to capture the entire environment of viewer 105.
Computer graphic systems are generally not designed to process and display spherical surfaces. Thus, as illustrated in FIG. 2, texture mapping techniques are used to create a texture projection of the inner surface of sphere 110 onto polygonal surfaces of a regular solid (i.e., a platonic solid) having sides that are tangent to sphere 110. As illustrated in FIG. 2, a common texture projection is to use a cube 220 surrounding sphere 110. Specifically, the environment image on the inner surface of sphere 110 serves as a texture map which is texture mapped onto the inner surfaces of cube 220. A cube is typically used because most graphics systems are optimized to use rectangular displays and a cube provides six rectangular faces. Other regular solids (i.e., tetrahedrons, octahedrons, dodecahedrons, and icosahedrons) have non-rectangular faces. The faces of the cube can be concatenated together to form the environment map. During viewing, the portions of the environment map that correspond to view window 130 (FIG. 1 and FIG. 2) are displayed for viewer 105. Because, the environment map is linear, texture coordinates can be interpolated across the face of each cube based on the vertex coordinates of the faces during display.
Other texture projections can also be used. For example, cylindrical mapping, as illustrated in FIG. 3, can be used if view window 130 is limited to a visible range around the equator. Specifically, in FIG. 3, a texture projection in the shape of a cylinder 320 surrounds sphere 110. Portions of the environment image on the inner surface of sphere 110 serves as a texture map which is texture mapped onto the inner surfaces of cylinder 320. Often, cylinder 320 is approximated using a plurality of rectangular sides to simplify the texture mapping. FIG. 4 illustrates a texture projection ideally suited for environment mapping. Specifically, FIG. 4 shows a texture projection comprising a plurality of polygonal curved surfaces, such as polygonal curved surfaces 410, 420, and 430. The polygonal curved surfaces form a sphere 400 having the same radius as sphere 110 (FIG. 1). The environment image on the inner surface of sphere 110 serves as a texture map for the polygonal curved surfaces. Creation and use of polygonal curved surfaces in environment projection is described in co-pending U.S. patent application Ser. No. 09/505.442, entitled xe2x80x9cENVIRONMENT DISPLAY USING TEXTURE PROJECTIONS WITH POLYGONAL CURVED SURFACES.xe2x80x9d
An extension to environment mapping is generating and displaying immersive videos. Immersive video involves creating multiple environment maps, ideally at a rate of 30 frames a second, and displaying appropriate sections of the multiple environment maps for viewer 105, also ideally at a rate of 30 frames a second. Immersive videos are used to provide a dynamic environment rather than a single static environment as provided by a single environment map. Alternatively, immersive video techniques allow the location of viewer 105 to be moved. For example, an immersive video can be made to capture a flight in the Grand Canyon. The user of an immersive video display system would be able to take the flight and look out at the Grand Canyon at any angle.
Difficulties with immersive video are typically caused by the vast amount of data required to create a high resolution environment map and the large number of environment maps required for immersive video. Thus, most environment mapping systems use very large environment maps, i.e. 1024xc3x971024 or 2048xc3x972048. Conventional high-quality immersive video systems would also require such high resolution environment maps to create high-quality immersive videos. However, conventional video equipment are designed and built to fixed standards regarding image resolution, compression, and other features, which may not provide enough bandwidth for high-quality immersive videos. For example, standard NTSC video streams provides an equivalent resolution of 640 by 480 pixels. While this resolution is adequate for conventional videos, it is inadequate for high-quality immersive videos, which must include the entire environment of a viewer not just the portions being viewed. Hence, there is a need for a method and system of displaying immersive videos while satisfying the constraints of conventional video equipment.
Accordingly, the present invention provides an immersive video system which utilizes multiple video streams to display high resolution immersive videos using conventional video equipment. In one embodiment of the present invention, an immersive video system for displaying a view window includes a video source, a video decoder coupled to the video source, and an immersive video decoder coupled to the video decoder. The video source is configured to produce a plurality of video streams. The video decoder is configured to decode an active video stream selected by the immersive video decoder from the plurality of video streams. The video streams contain environment data for the environment. Each video stream overlaps at least one other video stream so that the active video stream can be switched between the plurality of video streams without discontinuities. In some embodiments of the present invention, each video stream overlaps at least two other video streams. Generally the amount of overlap is approximately the size of the view window. Additionally, some embodiments of the present invention include view control interfaces to position the view window.
The video source in many embodiments of the present invention includes a video reader and a video storage medium. For example, a specific embodiment of the present invention uses DVD as the video storage medium. However, other embodiments may use other video storage mediums, such as a hard disk or solid state memories. The video storage medium contains multiple video streams each having a viewable range from a reference point. Generally, the viewable range of the video streams overlap. For example, in one embodiment of the present invention, the video storage medium stores four video streams. The viewable range of the first video stream overlaps the viewable range of the second and fourth video stream. Similarly, the viewable range of the third video stream also overlaps the viewable range of the second and fourth video streams.
The present invention will be more fully understood in view of the following description and drawings.

Immersive video system using multiple video streams


A method of programming a multi-level, dual cell memory device. The method includes independently programming a first charge storing cell and a second charge storing cell to respective data states, the data states selected from a blank program level or one of a plurality of charged program levels. Also disclosed is a method of reading the multi-level, dual cell memory device using a plurality of reference currents.

A pervasive trend in modern integrated circuit manufacture is to increase the amount of data stored per unit area on an integrated circuit memory unit, such as a flash memory unit. Memory units often include a relatively large number of core memory devices (sometimes referred to as core memory cells). For instance, a conventional dual cell memory device, such as a charge trapping dielectric flash memory device, can store data in a "double-bit" arrangement. That is, one bit (i.e., a binary data value have two states, such as a logical one and a logical zero) can be stored using a memory cell on a first "side" of the memory device and a second bit can be stored using a complimentary memory cell on a second "side" of the memory device.
Programming of such a memory device can be accomplished, for example, by hot electron injection. Hot electron injection involves "pulsing" the device by applying appropriate voltage potentials to each of a gate and a drain of the memory device for a specified duration. During the programming pulse, the source is typically grounded. Reading of the memory device can be accomplished by applying an appropriate voltage to each of the gate, source and/or drain and comparing the drain to source current (as an indication of device threshold voltage) against a reference value to thereby determine if each memory cell is in a programmed or an unprogrammed state.
Even though conventional charge trapping dielectric flash memory devices are capable of storing two single-bit binary data values per memory device, there is an ever increasing demand to store even more data per unit area of a memory core.

Method of programming dual cell memory device to store multiple data states per cell


A demographics analysis trains classifier models for predicting demographic attribute values of videos and users not already having known demographics. In one embodiment, the demographics analysis system trains classifier models for predicting demographics of videos using video features such as demographics of video uploaders, textual metadata, and/or audiovisual content of videos. In one embodiment, the demographics analysis system trains classifier models for predicting demographics of users (e.g., anonymous users) using user features based on prior video viewing periods of users. For example, viewing-period based user features can include individual viewing period statistics such as total videos viewed. Further, the viewing-period based features can include distributions of values over the viewing period, such as distributions in demographic attribute values of video uploaders, and/or distributions of viewings over hours of the day, days of the week, and the like.

1. Field of Art
The present invention generally relates to the field of digital video, and more specifically, to methods of correlating demographic data with characteristics of video content.
2. Background of the Invention
Video hosting sites, such as YouTube, currently have millions of users and tens of millions of videos. Users may sometimes have difficulty in determining which videos would be of interest to them and may be daunted by the sheer volume of videos available for viewing. Thus, the ability to suggest which videos would be of interest to a given user in view of the user's demographic attributes would be highly valuable. Similarly, the ability to infer the demographic attributes of a user based on past videos viewed by the user would be beneficial for a number of applications, such as providing user-specific content based on user demographics for users who have not already provided such data in a user profile.
However, conventional systems typically merely rely on external metadata associated with videos, such as keywords or textual video descriptions, to predict demographic groups that would be interested in a particular video, or to estimate the demographic attributes of a particular user. For example, conventional systems might recommend videos having keywords matching those specified in a viewer profile as being of interest to that viewer. However, if the video is new and has not yet been viewed and rated, and if the associated title is "spam" that misrepresents the true content of the video, then the conventional approach produces spurious suggestions. Thus, one shortcoming of conventional approaches is that they rely on external metadata that may be false when assessing the pertinence of a given video to a particular viewer, rather than examining actual data related to past viewings of video, such as content of the videos viewed, or information on user viewing sessions themselves.

Video content analysis for automatic demographics recognition of users and videos


A three-dimensional GRASE-type MR pulse sequence varies phase-encoding along the Z-axis identically in all signals between each two adjacent RF refocussing pulses in the MR pulse sequence. The phase error modulation caused by magnetic field inhomogeniety and the T2 amplitude modulation are separated onto two different spatial axes. This permits complete elimination of periodicity in both modulations and thereby improves image quality.

The invention relates to diagnostic imaging, and more particularly relates to magnetic resonance (MR) imaging. In its most immediate sense, the invention relates to MR pulse sequences.
The above-referenced parent patent application, which relates to two-dimensional MR pulse sequences, describes a problem inherent in conventional MR pulse sequences of the GRASE type. This problem is that because of the effect of T2 decay combined with the order in which lines of MR data are acquired, the data in the k-space matrix is highly amplitude-modulated ("AM"). When the k-space data is Fourier-transformed, this amplitude modulation is decoded as multiple edges of diminishing contrast and regular spacing ("ringing artifacts"). These AM ringing artifacts are distracting and interfere with the diagnostic quality of the final MR image.
Conventional three-dimensional MR pulse sequences of the GRASE type also inherently suffer from this problem. This is because a conventional three-dimensional GRASE-type MR pulse sequence is merely a set of two-dimensional GRASE-type pulse sequences, wherein each member of the set acquires all in-plane data at a constant phase-encoding gradient in the Z direction. As a result, conventional three-dimensional MR pulse sequences of the GRASE type inherently suffer from amplitude modulation of the MR data, and inherently produce ghost artifacts, especially when the sequences are long and T2 decay thereby causes a pronounced effect.
One object of the invention is to provide a three-dimensional GRASE-type MR pulse sequence which does not suffer from artifacts caused by amplitude modulation of the acquired MR data as a result of T2 decay.
Another object of the invention is to provide such an MR pulse sequence in which AM artifacts and phase modulation artifacts are completely absent.
Yet a further object of the invention is to improve on MR sequences of this general type.
The invention proceeds from a realization that a three-dimensional MR pulse sequence is subject to less stringent constraints than is a two-dimensional MR pulse sequence. The above-referenced parent patent application discloses a two-dimensional GRASE-type MR pulse sequence in which amplitude modulation of the acquired MR data is traded against phase modulation of the acquired MR data. This tradeoff is necessary because in the there-disclosed MR pulse sequence, phase-encoding takes place exclusively along a single in-plane axis. However, in a three-dimensional MR pulse sequence, phase encoding takes place in two directions, namely along the in-plane axis and the Z-axis. As a result, amplitude modulation need not be traded off against phase modulation. Indeed, it is possible to acquire lines of MR data using a scheme of GRASE-type phase encoding wherein artifacts resulting from amplitude modulation and from phase modulation are completely eliminated.
In accordance with the invention, there is provided a three-dimensional GRASE-type MR pulse sequence wherein, between each two adjacent RF refocussing pulses, the phase-encoding along the Z axis is varied identically. There consequently is no in-plane amplitude modulation of the acquired MR data. So, too, there consequently is no in-plane phase modulation of the acquired MR data. Advantageously, and in accordance with the preferred embodiment, the in-plane phase encoding remains constant between each two adjacent RF refocussing pulses and varies monotonically from the beginning of the MR pulse sequence to the end.

Grase-type three-dimensional MR pulse sequences


A wheeled car seat sized to hold an infant or young toddler in the seat of an automobile that can also be converted to a wheeled stroller is disclosed herein. The wheeled car seat is made from materials to protect the occupant while at the same time keeping the weight of the wheeled car seat to a minimum. When removing the wheeled car seat from an automobile, the user need not remove the child passenger while the user converts the wheeled car to a stroller, but instead only need lift the car seat above the ground and allow a pivotal chassis to swing open and expose wheels to the ground. When the wheeled car seat is configured as a car seat, the wheels are enclosed to prevent dirt from getting on the upholstery of the automobile.

Portable seats sized to hold an infant or young toddler in the passenger seat of an automobile, otherwise known as car seats, are well-known in the art. The purposes of these car seats is to protect the child and to properly position the child in the car seat for such protection. Car seats may also raise the level of the child slightly to allow a parent or guardian can administer to the child's needs more easily and perhaps to allow the child to see out of a car window. However, some car seats are bulky, lack versatility, and may not provide all the protection needed for the infant or child traveler.


A system and method for fast frequency locking are provided in which the phase difference between first and second synchronization signals is measured (22). The frequency difference between the two signals is then determined (24). The frequency of the second synchronization signal is then set to that of the first synchronization signal (26). Thereafter, the feedback loop of a phase-locked loop circuit is closed, with an error signal representative of the phase difference between the first and second synchronization signals being offset by an amount equal to an error signal generated when the frequency of the second synchronization signal is set to that of the first synchronization signal.

Digital communications networks are important elements of today's telecommunications systems. For reliable high speed digital communications, synchronous digital networks are often used, such as the synchronous optical network ("SONET").
In a synchronous digital network, a synchronization signal--e.g. a clock signal--is embedded in the data communications stream. This synchronization signal is used by various network elements (such as central offices) to reliably receive and transmit the digital data being transmitted on the network. Because the synchronization signal is often noisy (due to various kinds of signal interference), elements along the digital communications network employ filtering circuits to "clean-up" the synchronization signal. Typically, these filtering circuits are phase-locked loop circuits.
In normal operation, a phase-locked loop circuit generates an output synchronization signal based on the transfer function of the phase-locked loop circuit and the input synchronization signal. In this "closed-loop" mode of operation, there is very little difference between the output synchronization signal and the input synchronization signal, and any changes in the input synchronization signal are quickly matched by the output synchronization signal. If, however, the input synchronization signal is lost (or jumps significantly), such as when a fault occurs, the "closed-loop" mode is exited, and a "holdover" mode is entered.
In the holdover mode, the phase-locked loop circuit will be controlled to continue to operate at the average frequency at which it was transmitting when the synchronization signal was lost. When the input synchronization signal is restored, for example when the fault has been corrected or when a new input synchronization signal from another line is coupled to the phase-locked loop, then the phase-locked loop will be placed back in the closed loop mode to allow it to generate an output synchronization signal based on the input synchronization signal.
The period of time from when the input synchronization signal is restored to when the output of the phase-locked loop locks on to the input synchronization signal is known as the holdover recovery time. Ideally, this holdover recovery time would be zero. Unfortunately, in existing systems, the holdover recovery time may be significant, often on the order of several minutes, for example, for a frequency step of 4.7 parts per million ("ppm") between the input and output synchronization signal at the time the input synchronization signal is restored.
During this period of holdover recovery, data transmission errors are possible, since the output synchronization signal of the phase-locked loop is not at the same frequency as the input synchronization signal, and large phase offsets can be introduced. Therefore, a need has arisen for a method and an apparatus for frequency locking that results in faster frequency locking than prior art systems.


To determine files associated with one or more workflows, a trace of accesses of files in at least one server is received. The files are grouped into at least one set of files, where the files in the set are accessed together more than a predetermined number of times in the trace. Files associated with the particular workflow are identified based on the at least one set.

In the course of performing work in various systems (e.g., storage systems, computer systems, etc.), it is often desirable to identify files that are related to each other. Identifying related files (into corresponding groups) can be relatively complex, particularly in large systems containing a relatively large number of files, since files may span multiple directories, one directory may contain files for multiple groups, or files may be shared by several groups.
In some cases, the identification of related files can be performed manually, which is tedious and time consuming. Other conventional techniques focus on identifying relationships between files based on temporal locality, which is according to the observation that related files are usually accessed close to each other in time. The temporal locality techniques in some scenarios may capture spurious, coincidental relationships between files, such as when a user is listening to music while authoring a document.
Another conventional technique is based on the ability to track reads and writes to files within the same process, as well as track inter-process communications. However, this latter technique involves the use of relatively detailed system call information that may be available in local client machines, but which may not be available in other types of systems. As a result, application of this technique may not be possible in contexts where such detailed information is not available.

Identifying files associated with a workflow

Hewlett-Packard Development Company, L.P.


Methods of treating contact lenses employ a material composed of (a) a hydrophobic core having at least three carbon atoms and (b) at least three hydrophilic polyethylene oxide chains attached to the core.

1. Field of the Invention
The present invention relates to ophthalmic solutions, particularly to solutions for the treatment of contact lenses. This invention especially relates to solutions for wetting contact lenses.
2. Background
The surfaces of contact lenses must have a certain degree of hydrophilicity to be wet by tears. Tear wettability is in turn necessary to provide the lens wearer with comfort and good vision.
One way to impart wettability to contact lens surfaces is to add hydrophilic monomers to the mixture of comonomers used to form the contact lens material. However, the relative amount of hydrophilic monomer added affects physical properties other than wettability. For example, the hydrophilic monomer content of rigid gas permeable lens materials is much less than that of soft, hydrogel lenses. The rigid lenses accordingly contain only a few percent water of hydration whereas soft lenses contain amounts varying from 10 to 90%. Thus, while hydrophilic monomer addition does increase wettability, the technique is limited by the influence that it has on other properties.
Another way to impart wettability to lens surfaces is to modify the surface after polymerization. For example, surface coatings of hydrophilic polymers have been grafted onto the surface. See U.S. Pat. No. 5,171,264. Plasma treatment has also been used to increase the hydrophilicity of hydrophobic surfaces. Although effective, methods such as these are often expensive (requiring complicated and difficult manufacturing procedures) and impermanent.
Water-soluble polymers in lens care solutions have also been used to enhance the wettability of lens surfaces. Use of wetting polymers in this way provides a "cushion" between the lens and the eye which is equated with increased wettability as wearer comfort and tolerance. However, a common drawback with this approach is that the cushion layer dissipates rapidly, since there is little specific interaction between the polymer and the lens surface.
U.S. Pat. Nos. 4,168,112 and 4,321,261 disclose a method to overcome this drawback by immersing the lens in a solution of an oppositely charged ionic polymer to form a thin polyelectrolyte complex on the lens surface. The complex increases the hydrophilic character of the surface for a greater period of time relative to an untreated surface. Of particular interest are cellulosic polymers bearing a cationic charge, said polymers forming a strongly adhered hydrophilic layer on the contact lens surface. These polymers have proven to be exceptional components for wetting, soaking, and lubricating solutions.
While extremely effective for increasing the wettability of the lens, however, it would be desirable to enhance the biocompatibility of the complex formed by cationic cellulosic polymers to increase comfort to the eye.
Polyethylene oxide (PEO) is a unique water-soluble polymer. When in an aqueous environment PEO does not perturb the structure of water and therefore is very "compatible" in a water matrix. Because of these unusual properties PEO has been found to be an effective polymer for low protein adsorptions and low cell adhesion characteristics. However, attempts to employ PEO as a biocompatibilizer in solution have been frustrated by the fact that the low interfacial free energy of PEO/water interfaces results in a very low driving force for adsorption.
PEO coatings on polymeric surfaces have been shown to impart protein resistance and thus improve biocompatibility. Moreover, it has been suggested that a PEO surface on a contact lens would be desirable and methods for grafting PEO to the lens surface have been proposed. However, coating is time consuming and expensive and the coating is usually thin and may be abraded away by handling and/or cleaning.


A well pump assembly has a motor operatively connected to a well pump that has an intake. The well pump assembly has a capillary tube that extends alongside the tubing and has an outlet at the well pump assembly. A chemical injection pump is connected to an upper end of the capillary tube adjacent a wellhead of the well. A logic system detects well fluid falling back downward in the tubing and out the intake into the well, and in response turns on the chemical injection pump, which pumps a chemical down the capillary tube into the well adjacent or within the well pump assembly. Once upward flow of well fluid in the tubing has been established, the chemical injection pump may be turned off.

Many hydrocarbon wells are produced by electrical submersible well pump assemblies (ESP). A typical ESP includes a centrifugal pump having a large number of stages, each stage having an impeller and a diffuser. An electrical motor couples to the pump for rotating the impellers. A pressure equalizer or seal section connects to the motor to reduce a pressure deferential between lubricant in the motor and the hydrostatic pressure of the well fluid. Usually, the ESP is suspended on a string of tubing within the well. When operating, the pump discharges well fluid up the string of tubing.
The Well fluid is often a mixture of water, oil and gas. Centrifugal pumps do not operate well when die well fluid produces a large percentage of gas. Sometimes a centrifugal pump can become gas locked and cease to pump well fluid even though the impellers continue to rotate. A gas separator may be employed upstream of the pump to separate at least some gas from the well fluid prior to reaching the pump. The gas separator diverts a portion of separated gas to the annulus surrounding the tubing. The separated gas flows up the annulus and is collected at use well site.
Occasions arise when well fluid flows back down the string of tubing, through the pump and out the pump intake into the well. The well site may lose electrical power to drive the motor, causing this occurrence. An operator may shut down the pump for various reasons, also causing this occurrence. Further, some controllers for ESPs have a feature to break gas locked pumps by rotating the motor and pump in a pumping direction, but at a much slower speed. The slower speed allows well fluid in the tubing to flow downward through the pump in an effort to get the gas within the pump to flow out the pump intake to the tubing annulus.
The downward flow of well fluid through the pump may result in foaming of the well fluid in the annulus surrounding the pump intake and within the interior of the pump. Sometimes, the foam makes it difficult to get the pump to start pumping upward again. The downward flow of well fluid through the pump may also result in sand sliding back down the tubing into the pump. Sand accumulation in the pump is detrimental.

Apparatus and method for injecting a chemical to facilitate operation of a submersible well pump


A positive-type display device improved in response time and in uniformity of display images is provided. This display device has a cell structure containing a mixture consisting of at least one of nematic liquid crystals having a nematic dielectric anisotropy and at least one of pleochroic dyes in a closed thin space formed by two substrates which are parallel to each other and a spacer which is provided between ends of said two substrates. Each of said two substrates has an electrode film adherently attached to its surface within said closed space, and an alignment film is formed on at least one of said electrode films. The surfaces of said films which are brought into contact with said mixture are subjected to a treatment for orientation of the molecules of said liquid crystals and said dyes in a direction substantially normal to the plane of the substrate when a voltage is not applied. Said positive-type display device is characterized in that the longitudinal axes of the molecules in said mixture contained in said space are inclined at an angle of 3.degree. to 30.degree. relative to the normal to said substrate in their quiescent state at no voltage.

(a) Field of the Invention
The present invention relates to a display device using liquid crystals, and more particularly, it relates to a display device of a guest-host type using a mixture of nematic liquid crystals having a negative dielectric anisotropy and pleochroic dye.
(b) Description of the Prior Art
There have been proposed, heretofore, many display devices using a guest-host type combination of liquid crystals and pleochroic dyes, which devices in general comprise a cell structure having a mixture of at least one of nematic liquid crystals as host material and at least one of pleochroic dyes as guest material placed in a space between two parallel substrates, as disclosed in, for example, Japanese Patent Publication No. 47-3778 published Feb. 2, 1972.
Such conventional guest-host type display cells are of the so-called negative type, that is, they are colored when no voltage is applied, while they become faded out upon application of a voltage between the electrodes which are formed on the inside surfaces of the substrates. It has been found, however, that the positive-type display cells, i.e. those which are capable of effecting a colored display upon application of a voltage and being faded out when the voltage is removed, are more convenient to use. Although some positive-type display cells using the guest-host type combination of liquid crystals and dyes have been proposed heretofore also, they have many disadvantages. That is, in the cell structure of prior-art such device, the molecules of liquid crystals and dyes are rendered to a very mobile state in any directions immediately after a voltage is applied. Therefore, the molecules will move in random fashion in all directions, and subsequently they will gradually assume a stationary state, with the axes of all these molecules being not oriented in one direction. As a result, known positive-type display cells have a lower rate of response and have a tendency to effect a non-uniform or mottled display.

Positive-type display device using guest-host type mixture of liquid crystals and dyes


A sound signal processing method includes calculating a difference between every few ones of input multiple channel sound signals to obtain a plurality of characteristic quantities each indicating the difference, selecting a weighting factor from a weighting factor dictionary containing a plurality of weighting factors of a plurality of channels corresponding to the characteristic quantities, weighting the sound signals by using the selected weighting factor, and adding the weighted input sound signals to generate an output sound signal.

1. Field of the Invention
The present invention relates to a sound signal processing method for emphasizing a target speech signal of an input sound signal and outputting an emphasized speech signal, and an apparatus for the same.
2. Description of the Related Art
When a speech recognition technology is used in an actual environment, ambient noise has a large influence to a speech recognition rate. There are many noises such as engine sound, wind noise, sound of an oncoming car and a passing car and sounds of a car audio device in a car. These noises are mixed in a voice of a speaker, and input to a speech recognition system thereby causing to decrease the recognition rate greatly. As a method for solving a problem of such a noise is considered the use of a microphone array. The microphone array subjects the input sound signals from a plurality of microphones to signal processing to emphasize a target speech signal which is a voice of a speaker and outputs the emphasized speech signal.
There is well known an adaptive microphone array to suppress noise by turning the null at which the receiving sound sensitivity of the microphone is low to an arrival direction of noise automatically. The adaptive microphone array is designed under a condition (restriction condition) that a signal in a target sound direction is not suppressed generally. As a result, it is possible to suppress noise from the side of the microphone array without suppressing the target speech signal coming from the front direction thereof.
However, there is a problem of so-called reverberation that in an actual environment, the voice of the speaker who is in front of the microphone array is reflected by obstacles surrounding the speaker such as walls, and the voice components coming from various directions enter to the microphone. The reverberation is not considered in the conventional adaptive microphone array. As a result, when the adaptive microphone array is employed under the reverberation, there is a problem to have a phenomenon as referred to as "target signal cancellation" that the target speech signal which should be emphasized is improperly suppressed.
There is proposed a method for making it possible to avoid the problem of the target signal cancellation if the influence of the reverberation is known, that is, the transfer function from a sound source to a microphone is known. For example, J. L. Flanagan, A. C. Surendran and E. E. Jan, "Spatially Selective Sound Capture for Speech and Audio Processing", Speech Communication, 13, pp. 207-222, 1993 provides a method for filtering an input sound signal from a microphone with a matched filter provided by a transfer function expressed in a form of an impulse response. A. V. Oppenheim and R. W. Schafer, "Digital Signal Processing", Prentice Hall, pp. 519-524, 1975 provides a method for reducing reverberation by converting an input sound signal into a cepstrum and suppressing a higher-order cepstrum.
The method of J. L. Flanagan et al. has to know an impulse response beforehand, so that it is necessary to measure an impulse response in the environment in which the system is actually used. Because there are many elements such as a passenger and a load, opening and closing of a window, which influence transfer functions in a car, it is difficult to implement a method that such an impulse response must be known beforehand.
On the other hand, A. V. Oppenheim et al. utilize the tendency that a reverberation component is apt to appear at a higher term of the cepstrum. However, because the direct wave and the reverberation component are not quantized in perfection, how the reverberation component which is harmful to the adaptive microphone array can be removed depends upon a situation of the system.
A room of a car is so small that the reflection component concentrates on a short time range. Then a direct sound and reflected sounds are mixed and change a spectrum greatly. Therefore, the method using the cepstrum cannot separate between the direct wave and the reverberation component enough, so that it is difficult to avoid the target signal cancellation due to influence of the reverberation.
The conventional art described above has a problem not to be able to remove enough the reverberation component leading to the target signal cancellation of the microphone array in the small space in a car.

Sound signal processing method and apparatus


The present invention provides an equalizer filter for compensating a received distorted signal for frequency dependent signal modifications introduced by a transmission channel, the received signal having an amplitude. The filter comprises at least one amplifying compensation stage having a gain and a saturation level, at least one limiting amplifier, and gain control means for controlling the gain of the at least one amplifying compensation stage, the gain control means comprising at least one comparator circuit comparing filtered input and output signals of the limiting amplifier, the at least one comparator circuit comprising a bias current source. The bias current source is adapted to deliver a variable current.

An equalizer system in general compensates frequency dependent losses that a signal experiences when passing through a transmission channel. Transmission channels include, but are not limited to, a wire, a pair of wires, an optical fibre, the reading and writing channels of a storage device like a hard-disc or optical disc, a wireless connection such as a point-to-point or diffuse infra-red or radio connection. A pair of wires includes a twisted pair, a twinax coax or a differential transmission line on a printed circuit board.
The compensation level of an equalizer system in general can be self-adaptive, fixed or programmable e.g. by a voltage or via a set of switches. A self-adaptive equalizer system continuously estimates the matching compensation level. It typically includes an adaptable filter, a control loop and an output reconstruction unit.
EP-1392001 describes how to organise a control loop in an equalizer system such that self-adaptation is achieved, independently from the transmit amplitude and the transmitted bit pattern. A feed-back control signal is generated from the equalised output of an equalizer filter. Depending on whether the output signal has been under- or over-compensated, the feed-back control signal increases or decreases, such that after a reasonable time the feed-back control signal converges to a value where matched compensation is reached. The control loop is formed by a first means for measuring a short-term-amplitude signal of the output signal, a second means for measuring a long-term-amplitude signal of the output signal and a comparator means for comparing the short-term-amplitude signal and the long-term-amplitude signal, and for determining the evolution of the feed-back control signal.
US-2002/0034221 discloses a communications receiver that has multiple stages each having a transfer function 1+Ki[fi(jω)], wherein the Ki vary with a sequential gain control methodology. This document thus teaches to compensate by making a sum per stage of the unity input signal linearly added to a function that has higher frequency gain. This known method makes multiple tuning signals in circuitry using many comparators and is relatively complex. It is not suited for low voltage operation nor for implementation on a small chip area using small transistors that have large input offset mismatches.
EP-05447018.2 describes a multistage equalizer filter for compensating a received distorted signal having an amplitude for frequency dependent signal modifications introduced by a transmission channel. The filter comprises at least one amplifying compensation stage having a gain and a saturation level, the gain being monotonically rising for at least a last decade in frequency below an upper data frequency of the received signal, and a gain control means for controlling the gain of the amplifying compensation stage such that the amplitude of the received signal amplified in the at least one amplifying compensation stage remains below the saturation level of the amplifying compensation stage. The gain may be regulated by separately regulating low frequency gain, mid-frequency gain and higher frequency gain for each of the at least one amplifying compensation stages.

Multistage tuning-tolerant equalizer filter with improved detection mechanisms for lower and higher frequency gain loops


In a continuously variable belt transmission wherein each of primary and secondary pulley devices consists of a stationary pulley and a movable pulley, and wherein the movable pulley is furnished with a hydraulic servo system having a cylinder which is connected at one end with the movable pulley, and a plunger which slides liquid-tightly within the cylinder; a pulley assembly for a continuously variable belt transmission (1) comprising the fact that the end (19b) of the cylinder (19) to be connected with the movable pulley (10b) of the secondary pulley device is formed with a clinch portion (19f) whose inside diameter is made larger than the outside diameter of the sliding part (16b, 18) of the plunger (16). In connecting the cylinder (19) to the movable pulley (10b) while covering the plunger (16) which is attached to the secondary shaft (5) of the transmission (1), the oil seal ring (18) of the plunger (16) is not nibbled.

The present invention relates to a pulley assembly for a continuously variable transmission. Concretely, it relates to the secondary-side pulley device of a belt type continuously variable transmission for a motor vehicle, and more particularly to the clinch connection between the sideward flange portion of a movable pulley and the open end portion of a hydraulic cylinder.
As a continuously variable transmission of this type, there has been proposed one of a construction which has a primary pulley on an engine side and a secondary pulley on a wheel side, and in which a belt is wound over both the pulleys. A primary pressure for a speed change is supplied into and drained from the cylinder of the primary pulley, while a secondary pressure corresponding to a transmission torque is normally supplied into the cylinder of the secondary pulley. Herein, when an revolution speed of the secondary pulley is sharply raised by the variable speed, a centrifugal oil pressure takes place in an oil chamber of secondary pulley and the primary pressure balancing the secondary pressure fluctuates.
In the secondary pulley on the output side, therefore, a balance chamber is provided in adjacency to a secondary chamber so as to cancel the centrifugal oil pressure of the secondary pressure with the centrifugal oil pressure of the balance chamber. In this case, the secondary pulley side includes a partitioning plunger which is fixed integrally with a secondary shaft. The cylinder which is common to the secondary chamber and the balance chamber is snugly fitted on the plunger through an oil seal. Besides, the open end part of the cylinder on one side thereof is integrally connected to the movably pulley side of the secondary pulley.
Regarding the construction of the secondary pulley, there has heretofore been, for example, a prior art technique disclosed in the official gazette of Japanese Utility Model Registration Application Laid-open No. 52359/1987. Here, it is indicated that a hydraulic servo cylinder and a cover for canceling a centrifugal oil pressure are dividedly formed, that one end of the cylinder is fastened to a movable pulley side, that the oil seal is snugly fitted in a plunger of the cylinder, and that the cover is connected integrally with the outer end of the cylinder by the engaging a protrusion in a groove and the baking of a sealing rubber ring.
In the prior-art technique mentioned above, problems such as the complication of mounting and the increased number of man-hour are involved because the cover for canceling the centrifugal oil pressure is formed separately from the hydraulic servo cylinder.
In this regard, it is considered that the cylinder is integrally formed so as to serve also as the cover of the balance chamber and is snugly fitted on the oil seal of the plunger, whereupon the open end part of the cylinder is clinched and connected to the movable pulley side. With this construction, the connection is facilitated. Since, however, the chamfering of the open end part of the cylinder is limited in point of ensuring the clinch, the oil seal of the plunger is liable to undergo nibbles or defects in fitting the cylinder on this oil seal.
Accordingly, the clinch connection of the cylinder needs to be contrived so as to prevent the nibbles of the oil seal of the plunger attributed to the cylinder.

Pulley assembly for a continuously variable transmission


The present invention provides a charged particle source comprising a plasma processing chamber that has a plasma source, a gas supply and an ion extraction grid that are each operatively connected to the processing chamber. A conducting plate is located adjacent to a wall of the plasma source. The conducting plate has a surface with a plurality of grooves that face the wall of the plasma source. A substrate support is disposed within an interior portion of the processing chamber for supporting a substrate.

Charged particle sources are used for various surface modification, etching and deposition applications, and are particularly advantageous compared to other methods for providing direct control of particle energy and flux, angle of incidence to the substrate, and isolation of the substrate from the conditions of the reactor used to generate the etching and or depositing species.
In an ion beam source, ions are extracted from the plasma in the source. Since a plasma is quasi-neutral, equal number of electrons need to escape from the plasma, before plasma instabilities are caused. The escape path for the electrons is the beam grid, which is a conducting path for the electrons.
In a non-reactive gas plasma, such as an Argon (Ar+) plasma, the beam grid surface remains conductive, and provides a very reliable escape path for the electrons. However, when reactive gases are used, the beam grid surface can get oxidized, and stop providing an escape path for the electrons. In a Hydrocarbon (CH) precursor based plasma needed for the Tetrahedral Hydrogenated Carbon (Ta—C—H) direct ion beam for diamond-like carbon (DLC) films, as soon as the plasma is created, very low energy CHx+ ions deposit on all exposed surfaces, including the beam grid surface. This creates a thin Carbon coating on all such exposed surfaces in the ion source, and eliminates the escape path for the electrons in the plasma as the ions are extracted from the plasma. Plasma instability is caused as a result, and severe arcing is created, causing source instability, as well as particles within the system.
Therefore, what is needed is a charged particle source that reduces the Carbon coating on the exposed surfaces of the beam grid in the ion source.
Nothing in the prior art provides the benefits attendant with the present invention.
Therefore, it is an object of the present invention to provide an improvement which overcomes the inadequacies of the prior art devices and which is a significant contribution to the advancement of depositing Carbon using a charged particle source.
Another object of the present invention is to provide a charged particle source comprising: a plasma processing chamber; a plasma source having a wall operatively connected to the processing chamber; an ion extraction grid operatively connected to the processing chamber; a conducting plate within the plasma source and adjacent to the wall of the plasma source, the conducting plate having a surface having a plurality of grooves, the plurality of grooves facing the wall of the plasma source; a substrate on a substrate support disposed in an interior portion of the processing chamber; and a gas supply operatively connected to the processing chamber.
Yet another object of the present invention is to provide a charged particle source comprising: a plasma processing chamber; a plasma source having a wall operatively connected to the processing chamber; a plurality of ion extraction grids operatively connected to the processing chamber; a conducting plate within the plasma source at a distance from the wall of the plasma source, the conducting plate having a plurality of grooves, the plurality of grooves facing the wall of the plasma source; a substrate on a substrate support disposed in an interior portion of the processing chamber; and a gas supply operatively connected to the processing chamber.
Still yet another object of the present invention is to provide a charged particle source comprising: a plasma processing chamber; a plasma source having a wall operatively connected to the processing chamber; a plurality of ion extraction grids operatively connected to the processing chamber; a conducting plate within the plasma source at an adjustable distance from the wall of the plasma source, the conducting plate having a plurality of grooves, the plurality of grooves facing the wall of the plasma source, the conducting plate being opposite the plurality of ion extraction grids; a substrate on a substrate support disposed in an interior portion of the processing chamber; and a gas supply operatively connected to the processing chamber.
The foregoing has outlined some of the pertinent objects of the present invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the intended invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or modifying the invention within the scope of the disclosure. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the summary of the invention and the detailed description of the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.

Powered anode for ion source for DLC and reactive processes


A fast recovery extended method is used to enhance the performance of TCP fast recovery when multiple segment losses occur within a single round trip time between a TCP sender and a TCP receiver. A TCP fast recovery process is performed by a TCP sender, and then a TCP fast recovery extended process is performed by the TCP sender upon receiving acknowledgement of receipt of new data from a TCP receiver in the TCP fast recovery process. The fast recovery extended process determines, following receipt of the acknowledgement of receipt of new data, an excess number of duplicate acknowledgements based upon a count of consecutive duplicate acknowledgement packets. The fast recovery extended process takes a network packet transmission recovery action based upon the excess number of duplicate acknowledgements, and then stores the excess number of duplicate acknowledgements as a number of duplicate acknowledgements for further use.

1. Field of the Invention
This invention relates generally to methods used in implementation of the network Transmission Control Protocol, and more specifically to congestion control methods used in the Transmission Control Protocol.
2. Description of Related Art
The network Transmission Control Protocol (TCP) is well known. TCP runs only in end systems 100, 110 on a network 120 and not in intermediate network elements such as routers or bridges. The intermediate network elements do not maintain TCP connection state. A TCP connection between end systems 100, 110, sometimes called hosts 100, 110, provides full duplex data transfer between hosts 100, 110. A TCP connection is always point-to-point, i.e., between a single TCP sender and a single TCP receiver.
When a TCP connection is established, two application processes 101, 111 can send data to each other. Data is transmitted in segments. A segment includes header fields and a data field. The data field contains application data. The amount of application data that can be placed in the segment data field by the TCP sender is a maximum segment size. The TCP sender monitors flow control by monitoring an advertised receive window rwnd for the TCP receiver, which is the size of the TCP receive buffer.
Two header fields of interest are the sequence number field and the acknowledgement number field. As is known, in TCP, data is viewed as an unstructured, but ordered, stream of bytes. The sequence numbers used in TCP are over the stream of transmitted bytes. The sequence number that is placed in the segment number field is the byte-stream number of the first byte in the segment.
The acknowledge number placed in the acknowledgement number field, for example by host 110 in an acknowledgement packet being transmitted to host 100, is the sequence number of the next byte of data that host 110 is expecting from host 100. Since according to TCP, host 110 only acknowledges bytes up to the first missing byte in the data stream, host 110 may provide cumulative acknowledgements of a single segment when segments are received out of order, the cumulative acknowledgements for the single segment are referred to as duplicate acknowledgements.
Each time host 100 sends a segment into a TCP connection, a timer is started. If the segment timer expires before host 100 receives an acknowledgement for the data in the segment from host 110, host 100 resends the segment and initiates a slow start process. Typically, the timeout value for the timer is not much larger than a round-trip time between hosts 100 and 110. The round-trip time is the time from when a segment is transmitted to when an acknowledgement for that segment is received.
A segment can fail to reach host 110 due to data corruption or more usually as a result of network congestion. Most losses on the Internet are caused by congestion as routers run out of buffers and discard incoming traffic.
TCP typically runs on top of the Internet Protocol (IP). TCP must use end-to-end congestion control because the IP layer provides no feedback to end systems concerning network congestion. Four TCP congestion control processes are described in Request for Comments(RFC) 2581. The four are slow start, congestion avoidance, fast retransmit, and fast recovery.
Typically, for slow start, a slow start threshold ssthresh is maintained and for congestion avoidance, a congestion window cwnd is maintained for each connection. Congestion window cwnd is a sender side limit on the amount of data that the TCP sender can transmit into network 120 before receiving an acknowledgement.
When a TCP receiver 110 receives an out-of-order segment, TCP receiver 110 generates an immediate acknowledgement for the first missing segment, which is a duplicate acknowledgement. Since TCP sender 100 does not know whether the duplicate acknowledgement is caused by a lost segment, a reordering of the segments during transmission, or replication of an acknowledgement packet or a segment by network 120, TCP sender 100 waits to receive a small number of duplicate acknowledgements, typically three, before assuming a segment is lost. If a reordering of the segments is the problem, there are only one or two duplicate acknowledgements before the reordered segment is processed and a new acknowledgement generated.
When the third duplicate acknowledgement is received, the TCP sender immediately retransmits the oldest unacknowledged segment without waiting for the segment transmission timer to expire. This is known in the art as a fast retransmit.
Following the fast retransmit, fast recovery, but not slow start, is performed. Fast recovery governs the transmission of data by TCP sender 100 until a non-duplicate acknowledgement is received.
When one or more segments are lost in network 120, network 120 is assumed congested by TCP sender 100.
After recovery from the loss, TCP's congestion avoidance mechanism arranges to continue transmission at half the rate, which was obtained previously. The objective of fast recovery is to maintain transmission (at the reduced rate) while the recovery is being performed.
In fast recovery, the size of congestion window cwnd is reduced and slow start threshold ssthresh is set equal to the reduced size congestion window. As soon as is possible with the reduced size congestion window, another packet is transmitted over the network in response to each additional duplicate acknowledgement packet received from TCP receiver 110, and the size of congestion window cwnd is increased by the size of one segment. The principle behind this is that each duplicate acknowledgement implies the receiver has received a segment although the sender does not know which one. Since this means that a segment has left the network, the sender can insert one more segment without worsening the congestion.
When a non-duplicate acknowledgement is received by TCP sender 100, congestion window cwnd is deflated by setting window equal to slow start threshold ssthresh, and the number of duplicate acknowledgements is set to zero. If only a single segment is lost in a round trip time, fast retransmit and fast recovery perform satisfactorily and data transmission continues at the reduced rate in an attempt to avoid congestion on network 120.
However, fast recovery does not always result in a smooth recovery when there are multiple lost segments in a single round trip time. Since the number of duplicate acknowledgements is set to zero upon leaving fast recovery, TCP sender 100 must receive three new duplicate acknowledgements after termination of fast recovery before TCP sender 100 can determine that another drop has occurred and perform another fast retransmit. If the reduced size congestion window cwnd is such that less than three new segments can be transmitted by TCP sender 100, TCP receiver 110 does not generate three duplicate acknowledgements and a retransmission timeout occurs. Similarly, if the new drop occurs almost a round trip time after the first drop, there may not be sufficient time available for generation of three duplicate acknowledgements, and again a retransmission timeout occurs.
As network congestion increases, and multiple drops in a single round trip time occur, the performance of network 120 is degraded because fast recovery cannot handle multiple drops in a single round trip time. Hence, a new method is needed for recovering from such a situation.

TCP fast recovery extended method and apparatus


There is provided a method for forming an in situ oil shale retort in a subterranean formation containing oil shale. At least one void is excavated in the formation, leaving zones of unfragmented formation adjacent the void. An array of main blastholes is formed in the zone of unfragmented formation and at least one explosive charge which is shaped for forming a high velocity gas jet is placed into a main blasthole with the axis of the gas jet extending transverse to the blasthole. The shaped charge is detonated for forming an auxiliary blasthole in the unfragmented formation adjacent a side wall of the main blasthole. The auxiliary blasthole extends laterally away from the main blasthole. Explosive is placed into the main blasthole and into the auxiliary blasthole and is detonated for explosively expanding formation towards the free face for forming a fragmented permeable mass of formation particles in the in situ oil shale retort.

The presence of large deposits of oil shale in the Rocky Mountain region of the United States has given rise to extensive efforts to develop methods for recovering shale oil from kerogen in the oil shale deposits. It should be noted that the term "oil shale" as used in the industry is, in fact, a misnomer; it is neither shale nor does it contain oil. It is a sedimentary formation comprising marlstone deposit with layers containing an organic polymer called "kerogen" which, upon heating, decomposed to produce liquid and gaseous products. It is the formation containing kerogen that is called "oil shale" herein, and the liquid hydrocarbon product is called "shale oil".
A number of methods have been proposed for processing oil shale which involve either first mining the kerogen-bearing shale and processing the shale on the ground surface, or processing the shale in situ. The latter approach is preferable from the standpoint of environmental impact, since the treated shale remains in place, reducing the chance of surface contamination and the requirement for disposal of solid wastes.
The recovery of liquid and gaseous products from oil shale deposits has been described in several patents, such as U.S. Pat. Nos. 3,661,423; 4,043,595; 4,043,596; 4,118,071; 4,043,597; and 4,043,598 which are incorporated herein by this reference. These patents describe in situ recovery of liquid and gaseous hydrocarbon materials from a subterranean formation containing oil shale, wherein such formation is explosively expanded to form a stationary, fragmented permeable body or mass of formation particles containing oil shale within the formation, referred to herein as an in situ oil shale retort. Retorting gases are passed through the fragmented mass to convert kerogen contained in the oil shale to liquid and gaseous products, thereby producing retorted oil shale. One method of supplying hot retorting gases used for converting kerogen contained in the oil shale, as described in U.S. Pat. No. 3,661,423, includes establishing a combustion zone in the retort and introducing an oxygen-supplying retort inlet mixture into the retort to advance the combustion zone through the fragmented mass. In the combustion zone, oxygen from the retort inlet mixture is depleted by reaction with hot carbonaceous materials to produce heat, combustion gas, and combusted oil shale. By the continued introduction of the retort inlet mixture into the fragmented mass, the combustion zone is advanced through the fragmented mass in the retort.
The combustion gas and the portion of the retort inlet mixture that does not take part in the combustion process pass through the fragmented mass on the advancing side of the combustion zone to heat the oil shale in a retorting zone to a temperature sufficient to produce kerogen decomposition, called "retorting". Such decomposition in the oil shale produces gaseous and liquid products, including gaseous and liquid hydrocarbon products, and a residual solid carbonaceous material.
The liquid products and the gaseous products are cooled by the cooler oil shale fragments in the retort on the advancing side of the retoring zone. The liquid hydrocarbon products, together with water produced in or added to the retort, collect at the bottom of the retort and are withdrawn. An off gas is also withdrawn from the bottom of the retort. Such off gas can include carbon dioxide generated in the combustion zone, gaseous products produced in the retorting zone, carbon dioxide from carbonate composition, and any gaseous retort inlet mixture that does not take part in the combustion process. The products of retorting are referred to herein as liquid and gaseous products.
U.S. Pat. No. 4,043,598 discloses a method for explosively expanding formation containing oil shale toward horizontal free faces to form a fragmented mass in an in situ oil shale retort. According to a method disclosed in that patent, a plurality of vertically spaced apart voids of similar horizontal cross-section are initially excavated one above another within the retort site. A plurality of vertically spaced apart zones of unfragmented formation are temporarily left between the voids. Explosive is placed in each of the unfragmented zones and detonated, preferably in a single round, to explosively expand each unfragmented zone into the voids to form a fragmented mass. Retorting of the fragmented mass is then carried out to recover shale oil from the oil shale.
U.S. Patent Application Ser. No. 929,250 titled "METHOD FOR EXPLOSIVE EXPANSION TOWARD HORIZONTAL FREE FACES FOR FORMING AN IN SITU OIL SHALE RETORT" filed July 31, 1978, by the applicant describes a method for forming an in situ oil shale retort by expanding formation toward vertically spaced apart voids. Patent Application Ser. No. 929,250 is incorporated herein by this reference.
U.S. Pat. No. 4,043,596 discloses a method of forming an in situ oil shale retort in a subterranean oil shale deposit by excavating at least one vertically extending columnar void. The surface of the formation which defines the columnar void presents at least one free face which extends vertically through the subterranean oil shale deposit. A portion of the formation within the boundary of the in situ retort to be formed and which extends away from the free face is explosively expanded toward the columnar void in one or more segments. The expansion of the oil shale toward the columnar void fragments the oil shale, thereby distributing the void volume of the columnar void throughout the retort.
It is desirable to form an in situ retort with a reasonably uniformly distributed void fraction, or a fragmented mass of reasonably uniform permeability so that gas can flow reasonably uniformly through the fragmented mass during retorting operations. Techniques used for explosively expanding zones of unfragmented formation toward the horizontal free faces of formation adjacent the voids can control the uniformity of particle size or permeability of the fragmented mass. A fragmented mass having generally uniform permeability in horizontal planes across the fragmented mass avoids bypassing portions of the fragmented mass by retorting gas as can occur if there is gas channeling through the mass owing to non-uniform permeability.
In a technique for forming an in situ oil shale retort by explosive expansion of unfragmented formation toward a free face, inefficient distribution of explosive can occur due to use of blastholes extending perpendicular to such a free face. Because the explosive is in columns perpendicular to the free face, the energy from detonation of such explosive is less effeciently utilized than if the columns of explosive were parallel to the free face.
Alternatively, when columns of explosive are provided which are parallel to a free face, the explosive may not be distributed within the formation to the extent desirable because only a limited number of blastholes are used due to the economic considerations or the like.
It is, therefore, desirable to provide a method of forming an in situ oil shale retort which provides for improved efficiency in explosively expanding formation toward a free face.

Method for loading explosive laterally from a borehole


Methods and systems for enhancing workflow performance in the oil and gas industry may include modeling preferred sensor locations, sensor types, and sampling frequency for effective and efficient monitoring of a mud circulation system. For example, a method may include circulating a mud through a mud circulation system that includes a plurality of sensors that include at least one of: a pressure sensor, a stroke counter, a flow sensor, a viscosity sensor, or density sensor; and modeling the plurality of sensors using a state reduction approach to determine at least one selected from the group consisting of preferred locations, preferred sensory types, preferred sensor frequency resolution, and a combination thereof that effectively represent or substantially impact conditions of the mud circulation system, thereby providing a preferred sensor scheme.

In a mud circulation system, a plurality of sensors may be implemented for sensing mud properties at the surface and downhole. The sensors may include pressure sensors, stroke counters, flow sensors, viscosity sensors, density sensors, and the like at multiple surface and downhole locations. Many sensors including viscosity sensors and the various sensors designed to be implemented downhole are expensive. Additionally, as more sensors are added to a mud circulation system, the amount of data collected, the required communication bandwidth, and the processing power to analyze the data may grow exponentially.
It should be understood, however, that the specific embodiments given in the drawings and detailed description thereto do not limit the disclosure. On the contrary, they provide the foundation for one of ordinary skill to discern the alternative forms, equivalents, and modifications that are encompassed together with one or more of the given embodiments in the scope of the appended claims.

Sensor optimization for mud circulation systems


An antitheft device for two-wheeled vehicles includes a U-shaped fork whose central portion is articulated on the vehicle. The two branches pivot about an axis defined by the central portion in planes substantially parallel to the longitudinal plane of symmetry of the vehicle. In a first position, ends of the branches are located near respective sides of a wheel of the vehicle. In a second position the ends are located on sides of a support member. In a third position the ends of the branches are located to the rear of the vehicle. In each of the positions, a locking member, preferably in the form of a bar removably connects the two ends. The locking member includes a key operated lock whose bolt cooperates with an orifice or bore near one end of the U-shaped fork, the orifice or bore acting as a keeper for the bolt.

This invention relates to an antitheft device for two-wheeled vehicles and, more particularly, to such a device which can be used to secure the vehicle to a post or the like and alternatively to one of its wheels and which can be readily carried by the vehicle.
Known antitheft devices involve either, in a very simple way, the use of a chain or steel cable used to shackle one of the vehicle wheels or the use of a lock which makes it possible to lock the front fork of the vehicle in a position where it forms a substantially certain angle with the longitudinal plane of symmetry of the vehicle. The first type of these known devices has the drawback of being unaesthetic and, moreover, the chain or cable, which must be carried, has a certain inconvenience when the vehicle is being used. The second type of the known device is more expensive and fragile, and does not, like the first, allow the vehicle to be fastened to an object fastened in the ground such as a pole, the base of a light post and the like.

Antitheft device for two-wheeled vehicles