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Method for processing difficult-to-cut cast iron

In a pilot hole of a workpiece made of a difficult-to-cut cast iron, a cutting tool having a leading end to which a cutting insert is attached is inserted to cut the surface of the wall of the pilot hole. At this time, the cutting tool rotates about an axis (α) and also revolves about another axis (β), so that contouring is performed on the workpiece by the tool. The cutting insert is formed of a sintered body having a CBN content of not less than 85% by volume, and the cutting insert has a thermal conductivity of not less than 100 W/(mK).




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Multiple zone cooling apparatus

A cooling assembly for a machine tool including at least first and second nozzle rings mounted on the spindle housing, respectively defining first and second coolant conduits and respectively including first and second pluralities of nozzles in fluid communication with the respective conduit. Each first nozzle is oriented with an outlet thereof directed toward a first machining zone containing cutting edges of at last one tool having a first length. Each second nozzle is oriented with an outlet thereof directed toward a second machining zone different from the first machining zone and containing the cutting edges of at least one tool having a second length.




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High-voltage apparatus, and radiation source and radioscopic apparatus having the same

In a high-voltage apparatus according to this invention, a predetermined voltage is applied to a rotating anode after waiting until the number of rotations increases to such an extent that the rotating anode is not damaged. That is, X-rays of desired intensity are already outputted from a point of time when the voltage is applied to the rotating anode. Therefore, diagnosis can be performed immediately after the voltage is applied to the rotating anode. That is, unlike the prior art, there is no need to wait until X-ray intensity becomes suitable for diagnosis after X-ray emission is started, and there is no need to irradiate the patient with unnecessary X-rays. Therefore, the patient can be inhibited from being irradiated with excessive X-rays (with an improvement made in a response from when the operator gives instructions for starting fluoroscopy until emission of X-rays suitable for diagnosis).




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Multi-material decomposition using dual energy computed tomography

A method for obtaining multi-material decomposition images of an object is presented. The method includes acquiring an image pair from a dual energy computed tomography scan of the imaged object. The method then includes selecting a material basis for multi-material decomposition of the image pair. The method further includes applying a physicochemical model for the material basis. Also, the method includes performing multi-material decomposition using at least one constraint imposed by the physicochemical model.




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System and method for correcting for metal artifacts using multi-energy computed tomography

A method is provided. The method includes acquiring a first dataset at a first energy spectrum and a second dataset at a second energy spectrum. The method also includes extracting a metal artifact correction signal using the first dataset and the second dataset or using a first reconstructed image and a second reconstructed image generated respectively from the first and the second datasets. The method further includes performing metal artifact correction on the first reconstructed image using the metal artifact correction signal to generate a first corrected image.




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Hybrid multi-row detector and flat panel imaging system

A system and a method for acquiring image data of a subject with an imaging system are provided. The system can include a gantry that completely annularly encompasses at least a portion of the subject, and a source positioned within the gantry. The source can be responsive to a signal to output at least one pulse. The system can include a multi-row detector positioned within the gantry. The multi-row detector can be in alignment with the source and sets multi-row detector data based on the detected at least one signal. The system can include a flat panel detector positioned within the gantry. The flat panel detector can in alignment with the source and sets flat panel detector data based on the detected at least one signal. The system can include an image acquisition control module that determines which of the multi-row detector and the flat panel detector to use.




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Dose reduction via dynamic collimation adjustment for targeted field of view and/or digital tilt CT

Among other things, one or more systems and/or techniques are described for dynamically adjusting, in a fan-angle direction, attenuation of radiation during an examination of an object such that portions of the object that are not represented in resulting (tilted/targeted) images of the object are exposed to less radiation than portions of the object that are represented in resulting (tilted/targeted) images of the object. As a rotating gantry is rotated, blades of a pre-object collimator are dynamically repositioned to selectively attenuate emitted radiation. A collimator adjustment component may be configured to determine how to reposition the blades based at least in part upon at least one of a desired tilt of the resulting (tilted) image(s), a translational position of the object, and a gantry rotation angle, for example.




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Electric field emission x-ray tube apparatus equipped with a built-in getter

The present disclosure relates to an electric field emission x-ray tube apparatus equipped with a built-in getter, and more particularly, to an electric field emission x-ray tube apparatus equipped with a built-in getter that makes it possible to reduce the size of an x-ray tube by forming a stacked structure, with electric insulation and predetermined gaps maintained for each electrode, by manufacturing an x-ray tube having a stacked structure by inserting insulating spacers (for example, ceramic) between an exhausting port, a cathode, a gate, a focusing electrode, and an anode and bonding them with an adhesive substance, and then inserting a spacer between a field emitter on a cathode substrate and a gate hole connected with a gate electrode.




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System and method for cardiac defibrillation response simulation in health training mannequin

Configurations for simulation of motions or movement in a health training mannequin for teaching purposes are disclosed. A cardiac defibrillation response simulation apparatus is configured to be housed separately from but interfaced with a health training mannequin to induce motion symptomatic response to electrical shock in the mannequin. In one embodiment a system comprises a motion inducer comprising a housing, an interface structure, and an actuator, wherein the interface structure is coupled to the actuator, movable relative to the housing, and configured to interface with a portion of a health training mannequin to induce motion in at least one portion of the health training mannequin. In another embodiment a method comprises interfacing a portion of a health training mannequin with an interface structure, the interface structure being coupled to an actuator and movable relative to a housing coupled to the actuator, the housing not being housed within a portion of the health training mannequin. Various hardware configurations are presented.




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Systems and methods for multi-user multi-lingual communications

Various embodiments described herein facilitate multi-lingual communications. The systems and methods of some embodiments enable multi-lingual communications through different modes of communication including, for example, Internet-based chat, e-mail, text-based mobile phone communications, postings to online forums, postings to online social media services, and the like. Certain embodiments implement communication systems and methods that translate text between two or more languages. Users of the systems and methods may be incentivized to submit corrections for inaccurate or erroneous translations, and may receive a reward for these submissions. Systems and methods for assessing the accuracy of translations are described.




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System, method and multipoint control unit for providing multi-language conference

A system for providing multi-language conference is provided. The system includes conference terminals and a multipoint control unit. The conference terminals are adapted to process a speech of a conference site, transmitting the processed speech to the multipoint control unit, process an audio data received from the multipoint control unit and output it. At least one of the conference terminals is an interpreting terminal adapted to interpret the speech of the conference according to the audio data transmitted from the multipoint control unit, process the interpreted audio data and output the processed audio data. The multipoint control unit is adapted to perform a sound mixing process of the audio data from the conference terminals in different sound channels according to language types, and then sends mixed audio data after the sound mixing process to the conference terminals.




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Method and apparatus for iteratively detecting and decoding signal in communication system with multiple-input and multiple-out (MIMO) channel

A communication apparatus with a multiple-input and multiple-output (MIMO) channel, includes a minimum mean square error (MMSE) detector configured to estimate quadrature amplitude modulation (QAM) symbols based on signals received through the MIMO channel. The apparatus further includes a QAM demodulator configured to demodulate the estimated QAM symbols, and estimate a first posterior probability of each of encoded bits of the estimated QAM symbols, and a first module configured to remove a first prior probability of each of the encoded bits from the first posterior probability to generate soft estimates of the encoded bits. The apparatus further includes a channel decoder configured to decode the encoded bits based on the soft estimates, and generate an improved posterior probability of each of the encoded bits, and a second module configured to generate a second prior probability of each of the encoded bits based on the improved posterior probability.




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Wideband multi-channel receiver with fixed-frequency notch filter for interference rejection

A wideband multi-channel receiver comprises an antenna configured to receive a radio frequency band. A band-pass filter is in signal communication with the antenna, and a low-noise amplifier is in signal communication with the band-pass filter. A mixer is in signal communication with the low-noise amplifier and is configured to translate a radio frequency band to an intermediate frequency (IF) band. A tunable local oscillator is in signal communication with the mixer. At least one fixed-frequency notch filter is in signal communication with the mixer, with the notch filter configured to reject at least one interference signal in the IF band while passing remaining signals in the IF band. An analog-to-digital converter is in signal communication with the notch filter and is configured to convert the remaining signals in the IF band to digital signals.




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System and method for managing multimedia communications across convergent networks

A method and device that interrogates the availability of a called party before placing a communication from the calling party to the called party. A callback may be initiated so that both communications are completed simultaneously. The routing of communication may take place through any one of a number of different networks and at another time of the day, even if the caller does not otherwise have access to those networks.




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Memory training results corresponding to a plurality of memory modules

Methods, apparatuses, and computer program products for improving memory training results corresponding to a plurality of memory modules are provided. Embodiments include detecting a hardware configuration change upon initiating a boot sequence of a system that includes the plurality of memory modules; generating for a plurality of training iterations, reference training values corresponding to aligning of a data strobe (DQS) signal with a data valid window of data (DQ) lines of the plurality of memory modules; identifying for each training iteration, any outer values within the reference training values generated for that training iteration; eliminating the identified outer values from the reference training values; generating a final reference training value based on an average of the remaining reference training values; and using the final reference training value as the DQ-DQS timing value for the boot sequence of the system.




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Techniques for navigation among multiple images

Aspects of the disclosure relate generally to providing a user with an image navigation experience. In order to do so, a reference image may be identified. A set of potential target images for the reference image may also be identified. A drag vector for user input relative to the reference image is determined. For particular image of the set of target images an associated cost is determined based at least in part on a cost function and the drag vector. A target image is selected based on the determined associated costs.




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Display device having a power line arrangement for reducing voltage drop

A display device includes: a pixel area comprising pixels in rows and columns; main power lines at a first side of the pixel area and a second side of the pixel area facing the first side; first sub-power lines coupled to a first main power line of the main power lines formed at the first side and extending into the pixel area in a column direction; and second sub-power lines coupled to a second main power line of the main power lines formed at the second side and extending into the pixel area in the column direction, wherein the first sub-power lines and the second sub-power lines extend in different columns of pixels, and wherein a column of pixels of the pixels are alternatingly coupled to a neighboring sub-power line of the first sub-power lines and a neighboring sub-power line of the second sub-power lines.




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Ladder filter, duplexer and module

A ladder filter includes at least one series resonator connected in series between an input terminal and an output terminal, at least one parallel resonator connected in parallel with the at least one series resonator, an additional resonator connected in series between the at least one series resonator and one of the input terminal and the output terminal, and an inductor connected in series to the additional resonator, the additional resonator having a resonance frequency higher than an anti-resonance frequency of the at least one series resonator.




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Filter for removing noise

The present invention discloses a filter for removing noise, which includes: a lower magnetic substrate; a coil layer disposed on the lower magnetic substrate and including at least one conductor pattern and an insulating layer covering the conductor pattern; an upper magnetic substrate disposed on the coil layer; and a magnetic permeability enhancing layer disposed on the magnetic substrate with lower magnetic permeability of the lower magnetic substrate and the upper magnetic substrate. According to the present invention, it is possible to implement a filter for removing noise with high performance, characteristics, and reliability by increasing magnetic permeability to improve impedance characteristics and improving an effect of shielding electromagnetic waves such as jamming.




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Multilayer band pass filter

In a multilayer band pass filter, via-electrodes and strip electrodes define inductors of LC parallel resonators in four stages. A capacitor electrode and a ground electrode define a capacitor of a first-stage LC parallel resonator. A capacitor electrode and the ground electrode define a capacitor of a fourth-stage LC parallel resonator. Capacitor electrodes define a second-stage LC parallel resonator. Capacitor electrodes define a third-stage LC parallel resonator. Among four or more of the LC parallel resonators, the coupling between certain LC parallel resonators is easily defined, and the attenuation characteristic of a filter is definable with a high degree of freedom.




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SAW filter circuit having improved ESD resistance

A SAW filter circuit having improved ESD resistance is specified, in which a series interconnection composed of SAW resonators is interconnected between a first signal port and a dual-mode SAW filter port. The static capacitance of the series interconnection is at most four times the static capacitance of the dual-mode SAW filter transducers interconnected therewith.




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Frequency-tunable filter

A frequency tunable filter is disclosed. The frequency tunable filter includes a filter unit that can tune a frequency band of a frequency signal being filtered, a communication module that receives a control signal for controlling the tuning of the frequency band, and a control unit that controls the tuning of the frequency band based on the control signals. The disclosed filter can control the tuning of the filter's frequency band wirelessly.




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Ladder type surface acoustic wave filter and duplexer using same

An object of the present invention is to improve the passing characteristic at high temperature in a ladder-type elastic wave filter and a duplexer including the filter. The ladder-type elastic wave filter of the present invention includes a piezoelectric substrate, a first series elastic-wave resonator formed on the piezoelectric substrate and connected in series between the input and output terminals of the filter, a parallel elastic-wave resonator formed on the piezoelectric substrate and connected in parallel between the series elastic-wave resonator and the ground terminal, and a dielectric film formed on the piezoelectric substrate so as to cover the first series elastic-wave resonator. The piezoelectric substrate is formed of a material with a negative temperature coefficient. The dielectric film is formed of a material with a positive temperature coefficient and its film thickness is formed thicker than that with which the frequency-temperature coefficient of the first series elastic-wave resonator becomes 0.




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Surface acoustic wave filter and duplexer using same

An SAW filter and a duplexer excellent in electrical characteristics will be provided. An SAW filter has a piezoelectric substrate 40, a surface acoustic wave element 10 having a first IDT electrode 1 on the piezoelectric substrate 40, a first signal line 31 electrically connected to the first IDT electrode 1, and a ring-shaped reference potential line 9 which has a first intersecting portion intersecting with the first signal line 31 through an insulation member 41 and surrounds the surface acoustic wave element 10.




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Coupling structure for multi-layered chip filter, and multi-layered chip filter with the structure

A coupling structure for a multi-layered chip filter includes a resonator layer including a resonator pattern with spaced areas and a coupling layer including at least two separated overlap portion patterns overlapped with the spaced areas of the resonator pattern respectively and a connecting portion pattern having multiple linear portions connecting the separated overlap portion patterns in an area not-overlapped with the resonator pattern.




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Cavity filter with connecting structure connected between slider and driving device

A cavity filter includes a slider, a driving device, and an adapter. The slider is used to slide relative to and couple with a plurality of resonators located in the cavity filter to adjust a resonating frequency of the cavity filter. The driving device is used to drive the slider slide relative to the plurality of resonators and includes a shaft having a free end. The adapter is installed between the slider and the driving device and rotateably connected to the free end of the shaft with a gap configured between the free end and the adapter.




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Mechanically short multi-carriage tuner

Mechanically short multi-carriage impedance tuners use meandering slabline structures. The meandering structure reduces the overall tuner length by a factor of 2.5 at 0.4 GHz. The critical issue of slabline bends is addressed with several low loss, low reflection alternatives. A preferred configuration comprises a vertical-horizontal slabline transition. Cable connections are discarded because of reflections and insertion loss. Measured results show acceptable performance. The tuner is mostly interesting for relatively lower microwave frequencies, such as 1 GHz.




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Filter, receiver, transmitter and transceiver

Embodiments of the present invention provide a filter, a receiver, a transmitter, and a transceiver. The filter includes a resonant cavity component, a microstrip filtering component, and two connecting pieces, where the resonant cavity component includes at least two resonant cavities connected in parallel, each resonant cavity is provided with a resonator and a tuning screw, the microstrip filtering component includes a dielectric substrate and a microstrip positioned on the dielectric substrate, one of the connecting pieces matches and connects one end of the microstrip to the resonator on one resonant cavity, the other connecting piece matches and connects the other end of the microstrip to the resonator on another resonant cavity, and impedance of the resonant cavity component is less than impedance of the microstrip filtering component.




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Variable filter and communication apparatus

A variable filter includes, on a dielectric substrate including ground conductor, first resonator including a transmission line connected to input terminal, second resonator including a transmission line connected to output terminal, and coupling portion including a transmission line having one end connected to the first and second resonators and another end being an open end, or structure having one end connected to the first and second resonators, including a serial connection of a transmission line and a variable capacitor, another end of the variable capacitor connected to the ground conductor, and adjusting means capable of changing electric length, in the first and second resonators and the coupling portion, wherein pass band width can be changed by changing ratio of electric transmission length of the coupling portion to electric transmission lengths of transmission line including the coupling portion, and the first and second resonators.




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Filter, duplexer, communication module and communication device

A filter includes a plurality of primary resonators connected to a serial arm, a plurality of secondary resonators connected to a parallel arm, a primary inductor connected to at least one of the plurality of primary resonators and a secondary inductor connected to at least one of the plurality of secondary resonators. The primary inductor is arranged so as not to be connected to a path between the secondary resonator to which the secondary inductor is connected in parallel and the primary resonator that is connected to the secondary resonator to which the secondary inductor is connected in parallel.




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Multiple layer weaving

A weaving apparatus is provided herein for simultaneously weaving fine denier panels and coarse denier panels. The weaving apparatus includes a first warp beam that holds in tension a first number of small denier warp threads and a second warp beam that holds in tension a second number of large denier warp threads. The first number of small denier warp threads is greater than the second number of large denier warp threads.




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Multidirectional fiber-reinforced tape/film articles and the method of making the same

High tenacity, high elongation multi-filament polymeric tapes as well as ballistic resistant fabrics, composites and articles made therefrom. The tapes are fabricated from multi-filament fibers/yarns that are twisted together, bonded together, compressed and flattened.




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Joining loop structure of industrial multilayer fabric

A multilayer fabric is joined by engaging joining loops formed at both ends of a disjoined industrial multilayer fabric having wefts and warps in layers. The joining loops are formed by folding back some or all the end portions of warps. The both ends of the fabric are joined by engaging the loops to form a common hole and inserting a core wire into the common hole. At least one upper side weft remains while a lower side weft below the remaining upper side weft is removed at the both ends of the fabric. The common hole and the core wire inserted therein are located below the remaining upper side weft. The folded portions of the warps are interwoven with wefts of a normal portion of the fabric.




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High strength ultra-high molecular weight polyethylene tape articles

Processes for the production of high strength polyethylene tape articles from high strength ultra-high molecular weight multi-filament yarns, and to the tape articles, fabrics, laminates and impact resistant materials made therefrom.




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Multilayer protective textile sleeve and method of construction

A multilayer textile sleeve and method of construction thereof is provided. The sleeve has an outer layer constructed at least in part from a first warp yarn extending along a length direction of the sleeve and a weft yarn extending transversely to the length direction. The sleeve further includes an inner layer constructed at least in part from a second warp yarn extending along the length direction and a weft yarn extending transversely to the length direction, with the second warp yarn being a different type of yarn than the first warp yarn. The outer layer and inner layer are connected to one another by interlinking the weft yarn of the outer layer with at least some of the second warp yarns of the inner layer and by interlinking the weft yarn of the inner layer with at least some of the first warp yarns of the outer layer.




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Systems and methods for detecting ultracapacitor cell short circuits

A system for detecting a short-circuited ultracapacitor cell in a machine is disclosed. The system may have a memory that stores instructions and one or more processors capable of executing the instructions. The one or more processors may be configured to perform cell balancing among ultracapacitor cells arranged within two or more ultracapacitor modules, each ultracapacitor module including at least two ultracapacitor cells connected in series. The one or more processors may be further configured to measure a module voltage generated by each of the plurality of ultracapacitor modules after performing the cell balancing and before applying a load of the machine to the ultracapacitor modules, and determine whether an ultracapacitor cell among the plurality of ultracapacitor cells is short-circuited based on a comparison of the measured module voltages.




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Systems and methods for determining cell capacity values in a multi-cell battery

Systems and methods to determine cell capacities of a vehicle battery pack. Cell capacities may be determined using state of charge (SOC) estimates for the cells and a charge count for the battery pack. The SOC estimates may be determined when the SOC of the battery pack is below a lower threshold and above an upper threshold. Error values may also be generated for the cell capacity values.




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Multi-orientation stand for a portable electronic device

A stand for a portable electronic device includes a device receiving side including a coupling component for engaging with the portable electronic device when the portable electronic device is in a first orientation relative to the device receiving side and when the portable electronic device is in a second orientation relative to the device receiving side. The stand also includes a first support side adjacent to the device receiving side to act as a base when the portable electronic device is in the first orientation, and a second support side adjacent to the first support side to act as a base when the portable electronic device is in the second orientation.




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Belt battery charger

A belt battery charger includes a belt having a first end, a second end and an elongated central portion extending between the first and second ends. A plurality of electrically connected rechargeable batteries are carried by the central portion of the belt. A belt buckle located at the first end of the belt includes a frame that is secured to the central portion of the belt. The buckle further includes a prong in the form of an electrical connector electrically connected to the batteries and pivotally secured to the frame. The second end of the belt includes a number of spaced apart eyelets passing therethrough. The prong is shaped so as to be able to enter one of the eyelets to secure the second end of the belt to the buckle in the conventional manner. A second electrical connector is located adjacent the second end of the belt and is also connected to the batteries. One of said connectors is adapted to be connected to a cell phone for charging the same.




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Battery voltage detector having pull-up resistor

A battery voltage detector includes, but is not limited to: a voltage detection circuit; and a voltage processor. The voltage detection circuit includes, but is not limited to: a capacitor configured to be charged by a battery cell; a pair of output terminals; an output switch; and a voltage processor. While the capacitor is charged, the output switch is configured to be off-state and insulate the capacitor from the pair of the output terminals. After the capacitor is charged, the output switch is configured to be on-state and connect the capacitor to the pair of the output terminals. The voltage processor is configured to obtain, as a cell voltage, a voltage between the output terminals of the voltage detection circuit while the output switch is on-state. A high-potential output terminal of the pair of the output terminals is connected to a power line via a pull-up resistor.




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Fault tolerant electrical machine

A fault tolerant electrical machine including: a plurality of phases; a detector arranged to detect a fault in at least one of the phases; and a controller arranged to intentionally cause a fault in at least one other of the phases such that the vector sum of the second harmonic power vectors of the remaining phases is zero.




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EPGS architecture with multi-channel synchronous generator and common unregulated PMG exciter

A generator system includes a generator having a stationary portion and a rotating portion. The generator includes a permanent magnet based exciter with permanent magnets disposed on the stationary portion. A first channel includes a first main field winding and a first main field power converter disposed on a rotating portion. The first main field power converter selectively delivers voltage from the exciter winding to the first main field winding. A second channel includes a second main field winding and a second main field power converter disposed on the rotating portion. The second main field power converter selectively delivers voltage from the exciter winding to the second main field winding. A generator control unit is connected to the first channel and the second channel. The generator control unit monitors an output voltage at each of the first channel and the second channel and generates the first and second control signals based on the output voltage.




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Multiple voltage generator and voltage regulation methodology for power dense integrated power systems

An integrated power system suitable for simultaneously powering marine propulsion and service loads. The system includes: (a) at least one generator configured with at least first and second armature windings configured to output respective first and second alternating current power signals of different voltages, the at least two armature windings positioned within the same stator slots so that they magnetically couple; (b) at least first and second rectifier circuits coupled to said generator to convert said first and second alternating current power signals into first and second direct current power signals; and (c) a first load to which said first direct current power signal is coupled and a second load to which said second direct current power signal is coupled.




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Method and device to compensate for a dip in the output voltage of a motor-vehicle alternator

A dip in the output voltage of a motor-vehicle alternator, owing to a connecting of a load or a change in speed, is compensated with the aid of an alternator regulator which provides a control signal that has a duty factor and increases the excitation current of the motor-vehicle alternator. After the occurrence of the voltage dip, in a first step, the duty factor of the control signal is increased by a differential amount, and in a subsequent second step, the rate of correction is limited. After the occurrence of the voltage dip, parameters describing the instantaneous working point of the motor-vehicle alternator are determined, and in the first step, the differential amount is set as a function of the working point.




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Acyclic exciter for an alternator

A self-excited alternator for generating electrical energy. The alternator includes a stator, a rotor, and an exciter. The rotor includes conductors which are integrated within the rotor via one of a casting process, a welding process, or a fastening process. The exciter includes a magnet producing a static magnetic field, and a rotatable conductive member coupled to the shaft and electrically coupled to the one or more conductors. The rotatable conductive member is operable to output the direct current to the one or more conductors upon rotation within the static magnetic field, thus exciting the alternator.




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Methods and systems for monitoring excitation of a generator based on a faulty status of a generator breaker

Systems and methods for monitoring excitation of a generator based on a faulty status of a generator breaker are provided. According to one embodiment, a system may include a controller and a processor communicatively coupled to the controller. The processor may be configured to receive, from a contact associated with a generator breaker, a reported status of the generator breaker, receive operational data associated with one or more parameters of a generator associated with the generator breaker, and correlate the reported status of the generator breaker and the operational data. Based on the correlation, the processor may establish an actual status of the generator breaker, and, based on the actual status, selectively modify a mode of excitation of the generator.




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Overvoltage limiter in an aircraft electrical power generation system

A generator includes a permanent magnet generator, an exciter and a main generator mounted for rotation on a shaft. The main generator is configured to produce a voltage output. A generator control unit includes a circuit configured to provide current from the permanent magnet generator to the exciter. A switch is provided in the circuit and is configured to change between open and closed conditions. The switch is configured to flow current in the circuit in the closed condition and interrupt current flow in the open condition. An overvoltage limit controller is programmed to determine an amount of overvoltage of the output voltage exceeding a desired voltage. Either a fixed reference threshold is used or a reference threshold voltage is calculated based upon the duration in over voltage condition, and the switch is modulated between the open and closed conditions according to error between the actual output voltage and the reference threshold voltage to limit the output voltage to the desired reference threshold voltage.




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Power supply system for motor vehicle provided with control device of voltage applied to field coil of generator

A power supply system for a motor vehicle includes a generator that includes a rotor having a field coil and a stator having an armature coil; a rectifier that rectifies AC power generated in the armature coil; an excitation control circuit that takes control of a voltage applied to the field coil; a capacitor that is connected to the DC side of the rectifier, and receives and transfers the rectified power; a battery connected to an electric load of the motor vehicle; a DC-DC converter that is connected between the capacitor and the battery and capable of converting unidirectionally or bidirectionally an input DC voltage into any DC voltage; and a selection switch which connects the capacitor or the battery to the excitation control circuit as a power supply source.




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Regulator/brush-holder assembly for a motor-vehicle alternator, manufacturing process and corresponding alternator

The regulator/brush-holder assembly (1) comprises a support (2) and an electrical circuit (5, 6) comprising a regulating element (5) connected by microwires to a trace circuit (6). The electrical circuit further includes a filtering circuit (10) separate from the regulating element and connected by microwires to the trace circuit. According to one particular embodiment, the filtering circuit comprises an insulating substrate (11) and surface-mounted components (C1, C2, S1, S2, V). A ground plane (19) and/or one or more ground pads may be provided for connection to a ground trace of the trace circuit. The filtration frequencies of the filter circuit extend from 100 kHz to 1 GHz.




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Double fed induction generator (DFIG) converter and method for improved grid fault ridethrough

A double fed induction generator (DFIG) converter method are presented in which rotor side current spikes are attenuated using series-connected damping resistance in response to grid fault occurrences or grid fault clearances.