808 results about "Pulse period" patented technology

A disk drive is disclosed comprising a disk and a voice coil motor (VCM) for rotating an actuator arm about a pivot in order to actuate a head over the disk. During a park operation, a latching characteristic associated with latching the actuator arm is measured and used to configure a latching parameter that reduces acoustic noise. The latching parameter is used to latch the actuator arm by seeking the head to a latching track, maintaining the head over the latching track for a predetermined interval, applying an acceleration pulse to the VCM for an acceleration pulse period, applying a braking pulse to the VCM for a brake pulse period, and applying a latching current to the VCM.

An implantable stimulation device including a stimulation module and a data communication module. The stimulation device includes electrodes to delivery stimulation pulses, a voltage source, a DC-blocking capacitor and autoshort switch. The voltage source is connected to the electrodes via stimulation-pulse-switch(s) that controls delivery pacing pulses. The DC-blocking capacitor is connected with the voltage source and an electrode. The autoshort switch allows discharging of the DC-blocking capacitor via the electrodes when closed. The data communication module includes a data transmission control module connected to the autoshort switch and / or the at least one stimulation-pulse-switch, to alternatingly open and close the autoshort switch or the at least one stimulation-pulse-switch respectively, during an autoshort period following the delivery of a stimulation pulse or during a stimulation pulse period, respectively, to modulate an autoshort pulse or a stimulation pulse peak amplitude, respectively.

Output pulses from an optical system having a seed source and an optical amplifier coupled to the seed source may be controlled by controlling a power of a seed signal from the seed source. The seed signal may be varied between a minimum value and a maximum value in a way that the seed signal exhibits one or more pulse bursts. Each pulse burst may contain one or more pulses. During an inter-pulse period between successive pulses within a pulse burst or between successive pulse bursts, the power of the seed signal may be adjusted to an intermediate value that is greater than the minimum value and less than the maximum value. The intermediate value is chosen to control a gain in the optical amplifier such that a pulse or pulse burst that follows the period exhibits a desired behavior.

An electric arc welder and a method for performing a pulse welding process producing reduced spatter. The welder produces a current between an advancing electrode and a workpiece. The welder includes a short-detecting capability for detecting a short condition upon occurrence of a short circuit between the advancing electrode and the workpiece. The welder may also include a switching module in the welding circuit path of the welder having an electrical switch and a resistive path. Times of occurrence of short intervals can be tracked and a blanking signal can be generated based on the tracked short intervals to anticipate a next short interval in a next pulse period of the pulsed welding process. The blanking signal can be used to reduce a welding current in the welding circuit path by introducing additional resistance into the welding circuit path via the switching module, for example.

An audio device (200) includes a first and second ICs (210) and (250) and a substrate (205). The first IC includes a sigma-delta, A / D converter (218) operable to convert an analog signal (234) into a pulse density modulated signal (236). A pulse density width modulator encoder (222) is operable to encode the PDM signal into a PDWM signal (244). The PDWM has short and long pulse widths defining first and second bit levels. The leading edges of each pulse bounds each pulse period. The second IC (250) includes a means (254) to receive the PDWM signal, an edge detector (304) operable to detect the leading pulse edges of the PDWM signal, a time-averaging circuit (308) operable to calculate each pulse period from the leading pulse edges and to generate a sample pulse (120) at near the midpoint of each pulse period, and a latch (312) operable to sample and hold the PDWM signal at the sample pulse to decode a PDM signal (278). The substrate is operable to support the first and second ICs and to conduct the PDWM signal between the first and second ICs.

Methods and systems for detecting venous pulsation are provided. In one embodiment, a metric of the pulse shape of one or more plethysmographic signals is derived and the presence of venous pulsation is detected based on the metric of pulse shape. Examples, of metrics of pulse shape include a skew metric and a ratio of a minima-to-maxima time over a pulse period interval. In an exemplary embodiment, the presence of venous pulsation is detected based on a metric of the pulse shape of one or more plethysmographic signals and on a phase comparison of the plethysmographic signals.

The present invention relates to power reforming methods and associated multiphase lights, especially to power reforming methods and associated multiple lights that selectively turn ON and OFF to reform current to follow voltage appropriately, which provides better heat dissipation, improving power factor and color mixing capability. The method comprises acts of rectifying an AC voltage to a pulsating DC voltage, synchronizing an internal time base signal to the pulsating DC voltage, setting pulse duration in a pulse period and turning ON and OFF of an electronic device. The device comprises at least two loads, a rectifier, at least two drivers and a controller.

A control capacitor (CDown) is connected between a pixel electrode of a liquid crystal capacitor (CLC_Bn) in at least one sub-pixel and a common signal line (COM) through a TFT (3) whose gate electrode is connected to a gate signal line (Gn+1), and a control circuit selectively switches output modes in accordance with whether the pulse periods of a gate pulse to be output to the gate signal line (Gn) and a gate pulse to be output to the gate signal line (Gn+1) partially overlap or not.

The invention provides a frequency measurement method based on an FPGA. A standard reference clock is adopted to count the number of pulses of a measured signal in a unit time (1s) and the number of the pulses of the measured signal in the unit time (1s) is the frequency of the signal. Due to the fact that the starting moment of a gate and the finishing moment of the gate are random for the signal, a pulse period quantization error can be produced, and measurement accuracy needs to be analyzed further: the pulse period of a signal to be measured is set to be Tx, the frequency is set to be Fx, and when the measuring time T equals to 1s, the measurement accuracy & meets the equation that &=Tx / T=1 / Fx. The fact that measurement accuracy in a direct frequency measurement method is relevant to the frequency of the signal is known, the higher the frequency of the signal to be measured is, the higher the measurement accuracy is, and otherwise, the lower the frequency of the signal to be measured is, the lower the measurement accuracy is. The direct frequency measurement method is only suitable for measurement of the signal at the higher frequency and can not meet the demand that the measurement accuracy remains unchanged in the whole measurement frequency band. In order to overcome the defect of inaccuracy in low-frequency-band measurement, gating signals and the measured signal are used for carrying out dual control on enable signals of the counter, and therefore accuracy is improved.

The invention relates to an accumulator charging system, which comprises a three-phase alternating current power supply (10), an AC / DC convertor (20), a super capacitor group (30), a DC / DC bidirectional convertor (40) and an accumulator group (50), wherein the super capacitor group (30) is connected with the DC / DC bidirectional convertor (40) through a direct current bus (11). The DC / DC bidirectional convertor (40) is connected with the accumulator group (50)through an accumulator charging interface (102). The three-phase alternating current power supply (10) is connected with the AC / DC convertor (20) through an electric interface (101). The accumulator charging system can achieve conventional charging mode which comprises constant current, constant voltage and the like through controlling the DC / DC bidirectional convertor (40), can further generate positive and negative current impulse whose amplitude and width can be adjusted, achieves pulse charge to the accumulator group (50), provides particle or full electric energy by the super capacitor group (30) in a positive-going pulse period, absorbs electricity in a negative-going pulse period, lowers the charging grade of a charging power supply, and improves the energy utilization efficiency of the accumulator charging system.

A method for providing electromagnetic therapy to a patient includes placing the patient in proximity to an electromagnetic therapy apparatus. The electromagnetic therapy apparatus includes an electrical circuit for generating an electrical drive signal, a first transducer coil and a second transducer coil for generating respective electromagnetic fields in response to the drive signal, a first portion with a configuration corresponding generally with a chair seat, and a second portion with a configuration corresponding generally with a chair back. The first transducer coil is disposed within the first portion and the second transducer coil is disposed within the second portion. The method further includes stimulating the patient with a pulsed electromagnetic field from at least the first and second transducer coils. The pulsed electromagnetic field having a number of pulses, each pulse having a pulse period of ten microseconds to twenty microseconds.

In a method for controlling the arc length in pulse arc welding, the mean value of welding voltage Vw composed of peak voltage and base voltage is calculated, and the arc length is kept to be optimum by controlling the pulse period such that the mean value of the welding voltage is approximately equal to the preset value of the voltage. When a short circuit state Ts occurs during a base period and the voltage has changed from the base voltage to the short circuit voltage Vs, the mean value of the welding voltage is calculated by limiting the short circuit voltage Vs to the lower limit Vbt of the base voltage, wherein the lower limit value Vbt of the base voltage is varied so as to be furthermore low with the lapse of time in the short circuit state Ts. In consumable electrode type pulse arc welding the high speed welding, etc. are carried out with a mean arc length set to be short in order to improve the controllability of an arc length.

In a wireless network having an access point and at least one wireless end device, the access point is operable to differentiate between normal communications and interference from another device in order to capture a sample of the interference, determine whether the interference originates from a known type of device, and prompt remedial actions such as moving communications to a distant channel, increasing transmission power, changing data rate, and packet fragmentation based on whether the interference originates from a known type of device. Interference pulse duration may be used to at least initially narrow the possible sources of interference. Pulse period may be employed to differentiate between interference sources which exhibit similar pulse duration. If pulse duration and period are not sufficient to identify the interference source then other characteristics may be examined, such as pulse waveform, roll off and period in relation to local power frequency. In the case of microwave interference it is generally best to move to a distant channel. Increased transmission power and packet fragmentation can be used to maintain communications while scanning for a new channel.

An impulse arc welding control method comprises: repeating electrifying using the electrifying of peak current of in peak period and the electrifying of background current in background period as impulse period; controlling the arc length in the manner that the welding voltage value (Vw) is approximately equal to the set voltage value (Vs); making the arc length to vary periodically by making the set voltage value (Vs) to vary synchronistically with the switching signal (Stc); making the impulse parameter (Ps) to vary synchronistically with the switching signal (Stc); and changing the sending speed (Fs) from the time the switching signal (Stc) varying starts to the time arc length (La) transition varying approximately converges. Thus, the major varying of arc force make the shake movement of the bath becomes more intensive to improve the air bubble reducing effect. Consequently, the air bubble reducing effect is improved in the impulse arc welding method with arc length varied periodically.

The invention discloses a method to produce nanometer graphite sol. It supplies a system which includes highly pure graphite as anode, inert materials as cathode and electrolytical aqueous solution. There is an impulsing power source to connect the anode and cathode. The pulse period of the power source is 0.05-0.5 second, effective voltage 2-10V (3-5V is prelatered) and effective amphere density 15-75A (25-35 is prelatered). The efficiency of this invention is higher than common direct-current electrode method. The produced nanometer graphite sol is stable and disperses so it can produce nanometer graphite powder whose diameter is under 15nm.

A lighting device is capable of realizing a stable dimming control in a wide range of light output. The lighting device includes a DC power circuit for providing power to a switching element of the lighting device. A current controller switches the switching element to enable a current to flow from the DC power circuit through a solid state light source and maintain the current from the DC power circuit through the solid state light source current controller at a predetermined current. The current controller includes a first switching controller operable to change a width of an on-pulse provided to the switching element and a second switching controller operable to determine a burst-on time during which the on-pulses determined by the first switching controller are provided to the switching element. The burst-on time is longer than an on-pulse period of the first switching controller.

A discharging device is used to reduce the voltage level at a bootstrap point in an electronic circuit such as a shift register circuit. In such a circuit, a first transistor in a conducting state receives an input pulse and conveys it to the gate terminal of a second transistor, causing the second transistor to be in a conducting state. This gate terminal is known as a bootstrap point. After receiving the input pulse, an output pulse is produced at one drain / source terminal of the second transistor. During the time period of the output pulse, the first transistor is in a non-conducting state and the voltage level at the bootstrap point is high, imposing a stress upon the first transistor. A discharging circuit consisting of at least one transistor is coupled to the bootstrap point in order to reduce the voltage level at the output pulse period.

The invention provides a metal cold-welding additive manufacturing method. The method includes the steps that firstly, a part is subjected to 3D modeling on a main control computer, then the part is subjected to layered processing, the size and shape characteristics of each layer are obtained, a movement route is planed, welding technological parameters are selected, then a corresponding welding seam model of the part and a three-dimensional model of stacked layers are established, and the welding seam size and the stacked-layer forming size are obtained; the stacked-layer forming size is compared with the size of each layer, and then the bead weld route and the welding technological parameters are optimized and selected again; the main control computer inputs the bead weld route and the welding technological parameters into a welding machine, a wire feeder, a mechanical arm and positioning equipment; then a high-energy pulse precise cold-welding technology is adopted to perform interrupted spot welding, a spot weld is added to each pulse period, cooling for heat dissipation is performed during each pulse interval, and it is guaranteed that a base body is at a normal temperature state; and the part is formed by stacking interrupted spot welds point by point, line by line and layer by layer, and the problems that the heat input quantity, heat deformation and a grain structure are large, and it is difficult to plan the route in the manufacturing process are avoided.

A method of operating a welding system includes supplying a weld current and a weld voltage to an electrode via a plurality of pulse periods, where each pulse period of the plurality of pulse periods includes a background phase and a peak phase. The method also includes detecting the occurrence of an anomalous cathode event during the background phase of a first pulse period of the plurality of pulse periods based at least in part on when a voltage value of the weld voltage is greater than a detect voltage. The method also includes controlling the weld current to a desired current during a portion of the anomalous cathode event. The portion includes an interval of the background phase of the first pulse period, and the weld current is controlled independent of the weld voltage during the portion of the anomalous cathode event.

To provide a plasma display device which implements a peak luminance higher than prior art, reduces the power dissipation, improves the smoothness of gradation display, and conducts clear display suitable especially for TV display. By setting a plurality of APL levels according to the average value of the scene brightness, and by shortening a sustaining pulse period and increasing the number of sustaining pulses of each sub-field in APL levels having small APL, the peak luminance is raised. Further, by making the sustaining pulse period long in APL levels having large APL requiring large discharge light emission power, the light emission efficiency is improved and the maximum power dissipation is reduced. The luminance distribution in the scene when the APL level is small is detected. On the basis of that information, setting of the number of sustaining pulses and the sustaining pulse period is changed in the same APL level. As a result, the peak luminance is increased, and the gradation smoothness in the dark scene is improved.

A method for removing periodic noise pulses from a continuous audio signal generated in a pressurized air delivery system includes the steps of: detecting, in a time-windowed segment of the continuous audio signal generated in the pressurized air delivery system, a plurality of the periodic noise pulses having a pulse period and being representable in the form of a plurality of signal components combined by convolution; deconvolving the plurality of signal components to generate a plurality of deconvolved signal components; and removing at least a portion of the periodic noise pulses from the time-windowed segment of the continuous audio signal using the deconvolved signal components.

In one aspect, a method is disclosed of delivering therapeutic light to a treatment region to effect heating in the treatment region. The method includes providing a light emitting diode and driving the light emitting diode to generate therapeutic light during a pulse period. The method further includes directing the therapeutic light to the treatment region at an average power density of about 200 W / cm2 or more at the treatment region during the pulse period and maintaining the light emitting diode in a non-emitting state for a recovery period which is longer than the pulse period.

A welding control apparatus according to the present invention includes an integrator for starting calculation of a voltage error integral value Sv2, expressed by a formula (1) given below, from a time when a first pulse period ends and a second pulse period starts in a pulse cycle, based on various data of information regarding a gradient Ks of an external characteristic of a welding power supply and a welding current setting value Is2 and a welding voltage setting value Vs2 both in a second pulse period, which are preset as parameters in the formula (1), as well as on an instantaneous value Io2 of a welding current and an instantaneous value Vo2 of a welding voltage both detected in the second pulse period, a comparator for comparatively determining whether a value of the voltage error integral value Sv2 provided as the calculation result has become 0, and a waveform generator for, per pulse cycle, terminating the relevant pulse cycle and starting a next pulse cycle at a time when the value of the voltage error integral value Sv2 has become 0, whereby a variation in an arc length caused by disturbances is precisely suppressed in pulse arc welding of consumed electrode type:Sv2=∫{Ks(Io2−Is2)+Vs2−Vo2}dt  (1)

The invention provides a multi-channel vibration detection method based on coherent Rayleigh scattering and a detection system thereof. The detection system is improved as follows for the problem of relatively low utilization rate of an acquisition card in an optical-fiber vibration detection method based on coherent Rayleigh: a method for detecting vibration signals in a plurality of branches of sensor fibers by use of a delayer and a photoelectric switch in a staggered manner is adopted, and time-sharing vibration detection is performed on each sensor fiber by controlling the time of the delayer, and consequently, the detection of a plurality of branches of vibration signals is realized; besides, the acquisition card in a detection module does not need the input of a pulse control signal and is capable of realizing real-time data acquisition in a pulse period, and therefore, the utilization rate of the acquisition card is increased.

The invention discloses a system and a method for satellite positioning by using an optical signal of quantum characteristics, which mainly solves the problems of low positioning precision and time synchronous precision of the traditional global positioning system. The system mainly comprises a quantum light source generator, a reflector, a pyramid reflector, a delay controller, a beam splitter, a photon detector, a coincidence measurement unit, a photon pulse period accumulation unit, a TOA (Time Of Arrival) measurement unit, a data processing unit, a navigation positioning test experimental unit, and the like. The positioning method comprises the following steps of: acquiring a pulse accumulation outline by utilizing the optical signal of quantum characteristics, generated by the quantum light source generator, as external information input; obtaining TOA pulse information through detecting a model, carrying out data processing through a filter, and acquiring parameters, such as, position, time, and the like of a positioned object in real time; and realizing high precision positioning and timing. The invention has the advantages of providing long time and high precision navigation positioning for a navigational satellite, improving the accuracy of the satellite navigation positioning and the high confidentiality of information transmission, is suitable for the fields of navigation, positioning and timing of stationary or moving targets on the ground and spacecrafts in low earth orbit and can also be used in the application field of high precision autonomous navigation positioning of deep space and interplanetary flight spacecrafts, celestial body landers and surface cruisers thereof.

A converter unit configured to couple to a photovoltaic panel may include a controller that monitors: an output voltage and output current obtained from the photovoltaic panel by a switching power core within the converter unit, and an output voltage and output current produced by the switching power core. The controller may calculate a desired duty-cycle value based on the monitored values, and implement a mapping algorithm that translates the duty-cycle value to a pulse-width value and a modulus value. The pulse-width value and the modulus value may be used to simultaneously respectively modulate the pulse-width and pulse-period of a pulse-width modulated (PWM) signal, while maintaining an appropriate linear final duty-cycle ratio between the pulse-width and the pulse-period of the PWM signal. The PWM signal may be provided to the switching power core to control the switching of the switching power core.

The present invention provides a disc player comprising one or more light sources that project a constant or pulsing light onto the upper portion of a disc being played by the disc player. If a constant light source is used, the a pulsing viewing port for the disc receptacle of the disc player is employed. The pulse frequency, pulse length, pulse period, pulse interval, pulse color, pulse intensity or a combination thereof of the light source or the pulse frequency, pulse length, pulse period, pulse interval, or light transmissivity of the one or more viewing ports can be synchronized with the rotation of the spindle or platen in the disc player, with the optical data stored, or with the rotation of an image precursor on the disc. When the disc is viewed through a viewing port while the disc is being played, a two-dimensional or three-dimensional discrete image is formed by the persistence of vision. The disc player can also include an anti-piracy system to prevent unauthorized playing of digital / optical disc content. The anti-piracy system includes a verification system and access control data. When permission granting information is obtained from the disc, the verification system compares it to the access control data and either allows or disallows the disc player to play the disc.