152 results about "Small pulse" patented technology

To provide a method of processing a sapphire substrate, where reduction in luminance of light emitting devices can be suppressed if a sapphire substrate is divided into individual light emitting devices by irradiation of a laser beam, a pulsed laser beam having a small pulse energy of 0.6 μJ to 10 μJ, and an extremely small pulse width in a range of femto-second is irradiated to the sapphire substrate while a condensing point is positioned within each of regions corresponding to predetermined division lines on the sapphire substrate so that affected zones are formed, thereby the laser beam can be irradiated even at a high peak power density of 4×10¹³ W/cm² to 5×10¹⁵ W/cm², consequently each of the affected zones can be formed at only a desired condensing point within the sapphire substrate, and necessary processing can be performed while damage to nitride semiconductors or the sapphire substrate is minimized.

A reactive foil is used to assemble the components of rock bit cutters and to affix cutting elements to rock bit bodies. A small pulse of localized energy ignites the foil in a fraction of second to deliver the necessary amount of heat energy to flow solder or braze and form a strong, true metallic joint. The reaction in the foil may be activated using optical, electrical, or thermal sources.

The invention discloses an autonomous formation flight control method for satellites. Formation flight control is carried out through relative orbit mean elements, and due to the fact that a long-term trend of relative movement between the satellites is accurately reflected through the relative orbit mean elements, long-term changes of the relative movement can be well controlled with the method. The autonomous formation flight control method is characterized in that a mean semi-major axis difference control strategy in an orbital plane is designed, the mode that control targets are set in a partitioned mode is adopted, and it is guaranteed that the drift speeds within control zones are low; when outside the control zones, the control targets can return to the control zones at high speeds. According to the autonomous formation flight control method, due to the mode that small-pulse air injecting is used for orbit control multiple times, and a momentum wheel is used for posture control, influences of posture air injection control on orbits are reduced, and the orbit control execution accuracy is improved.

A push pull signal is detected from a disk-shaped storage medium on which wobbling grooves are formed as recording tracks and address information is recorded by forming pre-pits on lands between adjacent grooves. The detected push-pull signal is compared with a reference voltage thereby generating a land pre-pit detection signal. Of pulses included in the land pre-pit detection signal, those pulses having a small pulse width are regarded as noise pulses and removed thereby obtaining a corrected land pre-pit detection signal. The number of pulses included in the land pre-pit detection signal is counted, and the reference voltage is controlled in accordance with the counted number of pulses.

The invention is a method for selecting iron ore from red mud. It preprocesses the red mud to eliminate the tiny red mud and acquires the red mud sand, carries on grinding and classification to the red mud sand then eliminates the tail ore through raw selection and acquires the concentrate after choiceness. The picking process uses high background field density and small pulse frequency, the choiceness uses lower background field density and larger pulse frequency. The flow is simple, and the reclaim rate of iron is high, the reclaim rate of iron can reach to 90%. The invention has excellent economical efficiency and social efficiency.

An improved technique is described for acquiring MR image data such as needed for FSE-based Dixon imaging techniques. A gradient-induced echo shift is produced in the pulse sequences by a small gradient applied along the readout axis prior to a readout pulse. When necessary, another small pulse is applied along the readout axis, equal in area and opposite in polarity to the first, to compensate for the shifting effect. Similar pulses are applied for each acquisition window. While data with non-zero phase shifts between water and fat signals are collected as fractional echoes, no increase in echo spacing is necessary with the modified acquisition strategy. Images corresponding to different phase shifts are reconstructed using phase-sensitive partial Fourier reconstruction algorithms whenever necessary. These images are then used to separate different chemical species (such as water and fat) in the object to be imaged. Increased time efficiency is therefore achieved with the improved technique, with a significant reduction in degradation due to losses in slice coverage and increased image blurring and sensitivity to flow and motion due to T2-modulation along the echo train in conventional techniques.

The invention provides a self-excitation complete hollow passive compensation impulse generator, belonging to an electromechanical energy conversion device. The invention solves the problems of the existing small pulsed-power supply, including low power and energy density, no self-excitation without commercial power. A carbon fiber epoxy resin rotor yoke is fixed on a main shaft, a rotor excitation winding is adhered outside the carbon fiber epoxy resin rotor yoke, a carbon fiber ligation band is ligated and fixed outside the rotor excitation winding, an aluminum compensation sleeve is sheathed outside the carbon fiber ligation band; a composite stator yoke is fixed on the inner wall of the housing, a stator surface-wound armature winding is adhered on the inner wall of the composite stator yoke, a shielding box in the shape like the Chinese character 'HUI' is sheathed on the end portion of the stator surface-wound armature winding; an air space is arranged between the inner surface of the stator surface-wound armature winding and the outer surface of the aluminum compensation sleeve; the rotor is fixed inside the stator via two bearings; and one end of the main shaft is connected with a prime motor, and the other end thereof is fixed with a sliding ring and an electrical brush. The invention has the advantages of high energy storage and power density, small volume, and self-excitation.

The invention provides an identification method of a lighting shielding failure of an electric transmission line. The identification method is based on waveform characteristics of traveling wave current in on-line monitoring electric transmission line phase conductors and mainly includes performing on-line monitoring to the traveling wave current, extracting data of lightning stroke failure traveling wave current on a guide line, analyzing the waveform characteristics of the lightning stroke failure traveling wave current and determining that the electric transmission line has a lightning shielding failure if a section prior the maximum traveling wave current amplitude value responds to a like polarity small pulse which is directly connected with a main discharging pulse and the pulse response duration and the current amplitude value are within certain ranges. Compared with identification methods in prior art, the identification method is explicit in judgment thoughts and tested and verified by field data, so that the identification method is capable of accurately and effectively identifying whether a waveform current signal is a signal of the lighting shielding failure electric transmission line, effectively helping electric transmission line operating maintenance departments to judge lighting stroke failure properties of the line and know lightning stroke failure reasons, and scientifically guiding line lightning protection reconstruction.

It is an object of the present invention to provide a technology capable of reliably suppressing a surge voltage even in a case where noise having a small pulse width is generated. A drive protection circuit that drives and protects a switching element includes a gate driving circuit that drives the switching element in response to a gate driving signal and an overcurrent protection circuit that operates a soft cutoff circuit upon an overcurrent of the switching element, the soft cutoff circuit causing the switching element to transition from ON to OFF at a switching speed slower than that of the gate driving circuit. In the drive protection circuit, in a case where a pulse width of ON of the gate driving signal is less than or equal to a response time of the overcurrent protection circuit, the drive protection circuit operates the soft cutoff circuit to cause the switching element to transition from ON to OFF, regardless of the overcurrent.

The information recording apparatus irradiates a laser beam on a recording medium such as an optical disk and forms a recording mark corresponding to a recording signal to record information. A recording pulse signal includes a mark period irradiating the laser beam for forming the recording mark and a space period in which the recording mark is not formed. The mark period has a top pulse period and an intermediate bias period following the top pulse period. The mark period constituted by the top pulse period and the intermediate bias period does not have a continuous part of a plurality of pulses having a small pulse width unlike a pulse train, so that the correct recording mark can be stably formed on the recording medium without an inadequate deformation of a recording pulse shape, even in the case of a high speed recording.

An apparatus for sending signals downhole during drilling operations uses a main pump to pump mud from a mud pit at a substantially constant flow rate. The bulk of the pumped mud goes downhole to maintain adequate circulation for the drill bit. A bypass pipe is provided with a shut-off valve that is controlled by an electronic controller. By pulsing the opening and closing of the shut-off valve, the volumetric flow downhole is pulsed. The pulse amplitude and duration can be controlled. These pulses in the flow rate are detected by a suitable downhole device such as a flow rate measurement device, a pressure detector or a turbine. The initial "wake-up" pulse is made long enough so that the detection device downhole is always able to detect it. Subsequent to this wake-up pulse, adjustments are made to the pulse duration, in steps of about 2 seconds, for the smallest pulse period that is detectable downhole. In addition, the amplitude of the pulses is also controlled by regulating the maximum flow through the shut-off valve. The pulses are modulated by a binary sequence of numbers corresponding to the data to be transmitted.

The invention discloses an onboard oil injection quantity control self-learning method for a common rail oil injector. The conventional self-learning process is relatively convenient to implement, but cannot cover all working rail pressure of an engine, and has certain limitation on learning effect. The method comprises the following steps of: under the condition that the whole vehicle urgently throttles down the engine, implementing a small pulse width injection to a specific cylinder of the engine, monitoring and calculating the ratio of the angular acceleration of the specific cylinder to the angular acceleration mean of other cylinders without fuel injection, and querying a previously calibrated MAP chart of the angular acceleration ratio and the oil injection quantity to realize onboard self-learning of the injection property of the oil injector; and performing self-learning correction on the actual oil injection quantity of the oil injector according to the onboard self-learning result of the injection property of the common rail oil injector. By the method, the actual oil injection quantity of the oil injector is accurately controlled, and the problems of poor injection effect for multi-times and even serious discharge and noise and the like caused by mechanical aging in the using process of the common rail oil injector are solved.

Computation of variance or variance of the autocorrelation over a moving window of various sizes of a signal containing noise and possibly a small digital signal provides a sensitive, frequency independent indication of the likelihood of the presence of a small pulse, chirp or even spread spectrum digital signal possibly obscured by noise or larger signals in the signal to much lower signal-to-noise ratios than previously possible. Large signals in the signal which may also obscure any small signal are removed to a different signal path from the noise and small signals by subtraction after compression and reconstruction of the large signal. The compression noise thus added to the signal may also increase sensitivity of the variance of the autocorrelation to small signals obscured by the large signals. Controlling storage in response to the computed variance or variance of the autocorrelation allows substantial avoidance or limitation of storage of signals which contain only noise.

Plasma Display Panels (PDP) are becoming more and more interesting for TV technology. One important criterion for picture quality is the Peak White Enhancement Factor (PWEF). From a previous patent application of the applicant it is known to have a table of power level modes in a control unit for the display device. The average picture power value is measured and a corresponding power level mode will be selected from the table for sub-field coding. The power level modes have been made variable in respect to a number of parameters, namely: the number of sub-fields the sub-field type the sub-field positioning the sub-field weight the sub-field pre-scaling a factor for the sub-field weights which is used to vary the amount of small pulses generated during each sub-field. According to the invention it is now proposed to use one or both of the following parameters in addition for varying the power level modes: the sustain frequency the sustain pulse slope.

The invention discloses an optical fiber chirped pulse amplifier for ultra-short laser pulse output, which has the advantages of high pulse repetition rate, high power and ultra-short laser pulse output and belongs to the technical field of optical information. The optical fiber chirped pulse amplifier adopts an optical fiber type concave attenuating long-period fiber grating as a seed laser pulse of a high-power chirped femtosecond laser pulse amplifier or a spectral shaping component of a laser pulse amplified by a preamplifier, thereby eliminating the gain spectrum narrowing effect caused during amplification of the high-power chirped femtosecond laser pulse optical-fiber amplifier, increasing the spectral bandwidth of the amplified laser pulse. The laser pulse with smaller pulse width and higher peak power can be obtained through compression. The high-power chirped femtosecond laser pulse amplifier which has the advantages of high repetition rate, high power, simple structure and high efficiency and can be fully made of optical fiber is applicable to such industrial fields as precision machining, precision lithography, laser fusion and the like of semiconductor devices and metal materials and the basic scientific research such as biomedical imaging.

The invention provides a method for welding a thin-walled cylinder with a magnet sleeved inside in a seal housing component. The welding efficiency of the aluminum alloy thin-walled seal housing component can be obviously improved through the method, quality is stable, a connector is bright, fusion is even, and continuous and compact welding beads can be formed. According to the technical scheme, the method comprises the following steps that the butt joint positions of inner and outer housing welding joints are closely attached through a clamp, and annular welding joint pulse electron beam tack welding is carried out on the circumferential seam crossing of an assembled component; a deflection distance occurring to an electron beam caused by Lorentz force is compensated by an electron beam deflection angle; the total heat input amount of the electron beam is controlled with the impulse waveform of the pulse electron beam, the impulse waveform is steep in the front and gentle in the back, and welding is carried out through heat generated when beam flow ascends and descends; under the condition that small pulse power is set and steam pressure is reduced, a pulse back edge is prolonged by 3-5s, slow reduction is carried out, the focal position of the electron beam is adjusted to be within the range 0.55mm below the surface of a workpiece, the surface of a connector to be welded is melted and integrally welded, and the continuous welding beads are formed.

The invention discloses a charge pump ripple rejection technology based on multistep discharge of a flying capacitor. As for a charge pump type DC (direct current)-DC convertor, load discharge is finished in multiple steps after the flying capacitor is charged once, so that discharge current is broken up into multiple small pulses from one large pulse. Meanwhile, the slopes of rising edge and falling edge of a waveform of a switching tube grid in drive connection with the flying capacitor and load, are controlled, so that a switch is connected and disconnected slowly, then each discharge current pulse is smoothed, discharge current approximates load current, and charges accumulated on a load capacitor are reduced, so that output voltage ripples are reduced.

An adjustable lighting system for fluorescent lamp, which includes a lighting unit, a sensing apparatus and a control apparatus, is provided. The lighting unit can emit a light. The sensing apparatus can sense if a target exists and generate a sensing signal accordingly. The sensing apparatus further generates and outputs a modulating signal based on the sensing signal. The control apparatus can receive the modulating signal from the sensing apparatus, adjust a supporting current of a power source and support the pulse width and phase level of the supporting current to the lighting unit, to control the strength of the light emitted by the lighting unit. Particularly, if the target exists, the modulating signal drives the control apparatus to provide a larger pulse width and phase level of the supporting current, so as to increase the strength of the light, or the modulating signal drives the control apparatus to provide a smaller pulse width and phase level of the supporting current, so as to decrease the strength of the light.

The invention provides a filter circuit of an integrated circuit. The filter circuit of the integrated circuit comprises a low-level delay unit, a first filter unit, a high-level delay unit, a second filter unit and an RS trigger, wherein the input end of the low-level delay unit receives an input signal, the low-level delay unit is used for delaying and outputting the falling edge of the received input signal, the first filter unit is connected with the low-level delay unit and used for filtering a negative pulse with a pulse width smaller than the delay time of the low-level delay unit, the input end of the high-level delay unit receives the input signal, the high-level delay unit is used for delaying and outputting the rising edge of received input signal, the second filter unit is connected with the high-level delay unit and used for filtering a positive pulse with a pulse width smaller than the delay time of the high-level delay unit, the R input end of the RS trigger is connected with the output end of the second filter unit, and the S input end of the RS trigger is connected with the output end of the first filter unit. The filter circuit of the integrated circuit can filter pulses with smaller pulse widths. The invention further provides the integrated circuit.

The invention discloses an erasing and writing method of a phase change memory. The erasing operation is realized in a way that: applying a small-pulse-height pulse on a phase change material in the device, wherein the pulse enables the phase change material to right achieve the fusion temperature and partially form amorphous areas in the phase change material; and continuing to applying a plurality of small-pulse-height pulses, and accumulating amorphous areas in the phase change material until the device is transferred from low impedance state to high impedance state. The invention realizes the erasing and writing operations by utilizing the accumulating function; on one hand, low heat produced by the small pulse height is beneficial for stability of the material, and on the other hand, the small pulse height can ensure the application of the phase change memory in the environment requiring low programming current (voltage), thereby reducing the energy consumption of the device and greatly saving the cost for optimizing the device structure under the condition of no change of the device structure of the phase change memory.