Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

204 results about "Periodic alternating" patented technology

Control method of drive system, drive system and new energy vehicle

The invention discloses a control method of a drive system, the drive system, and a new energy vehicle. The method obtains a current temperature value of a power battery in real time; when the temperature value is lower than a first preset temperature threshold, the temperature is raised to restore the drive capability of the drive system. A motor controller applies a periodic alternating voltagevector to a motor, the voltage vector is utilized to modulate bus current of a power battery to alternate, and during the process, the battery is driven to be repeatedly charged and discharged periodically to increase the temperature of the battery. Until the temperature value reaches a second preset temperature threshold, the battery is warmed to a desired operating temperature and the motor controller stops applying the voltage vector. Three-phase winding of the motor and three sets of bridge arms are used during the heating of the power battery. The recovery of the drive capability of the drive system is more economical without the need for additional external heating equipment. During the entire process of applying the voltage vector, the power battery is continuously and uniformly heated, the battery heating efficiency is very high, and rapid recovery of the drive capability is achieved.
Owner:SAIC MOTOR

Magnetic bead-based sample treatment and nucleic acid automatic extraction system

The invention discloses a magnetic bead-based sample treatment and nucleic acid automatic extraction system, comprising a micro-fluidic chip and a micro motor drive device, wherein the micro-fluidic chip comprises a layer of cover plate, two layers of bottom plates and two layers of structure plates, wherein the chip can automatically finish the operation processes such as cell lysis, nucleic acid purification, nucleic acid eluting and the like, and finally a nucleic acid sample is obtained. Based on siphon principle or micro-fluidic surface tension properties, a driven drive pump without external drive force is designed by the chip, so as to achieve flowing and transferring of a detection sample, a reaction reagent and reaction liquid waste. Under mixed hardening of a micro vibration motor, through a periodic alternating magnetic field and a constant magnetic field provided by an external magnet, effective mixing between the magnetic bead and the reaction sample and the reaction reagent in a reaction cavity, and fixing of the magnetic bead in the liquid waste discharge process are achieved; and the chip is matched with a full-automatic micro motor drive device to automatically finish a plurality of reaction steps, so that a high-purity nucleic acid sample template is provided for gene amplification reaction.
Owner:BEIJING UNIV OF CHEM TECH +1

Broadband all-dielectric multilayer-film reflective diffraction grating and design method thereof

InactiveCN101887140AAchieving Reflection EfficiencyAchieve bandwidthDiffraction gratingsDielectricPeriodic alternating
The invention provides a broadband all-dielectric multilayer-film reflective diffraction grating and a design method thereof. The broadband all-dielectric multilayer-film reflective diffraction grating comprises a base, a high film reflecting layer and a grating layer, wherein the high film reflecting layer and the grating layer are formed by periodic alternation of a high-refractive index material and a low-refractive index material. The invention is characterized in that a matching layer and a residual film layer are arranged between the high film reflecting layer and the grating layer; the refractive index of the material of the matching layer is as the same as the low-refractive index material in the high film reflecting layer; the refractive index of the material of the grating layer and the material for etching the residual film layer is less than that of the high-refractive index material; and the period and the duty cycle and the etching depth of the grating layer, the thickness of the residual film layer, the thickness of the matching layer and the wavelength control value for preparing the high film reflecting layer are correlated and determined by a multi-parameter optimization design. In the invention, the diffraction efficiency of the broadband all-dielectric multilayer-film reflective diffraction grating is more than 97.5% when an incident TE polarized light approaches within the range of more than 100nm spectral bandwidth in a 1-grade reflective diffraction direction.
Owner:SHANGHAI INST OF OPTICS & FINE MECHANICS CHINESE ACAD OF SCI

Functional electrical stimulation device and system, and use thereof

Disclosed herein is a functional electrical stimulation (FES) device and system. In one embodiment, sequential bipolar pulse stimulation may be provided to an area of a living body via one or more electrode leads applied to the area via a FES device comprising a current pulse generating circuit comprising output nodes for operative coupling to the one or more electrode leads, and configured for operative coupling to a voltage supply. The current pulse generating circuit generally comprises positive and negative stimulation paths drawing from the voltage supply to respectively apply positive and negative currents through the area via the one or more electrode leads. In one example, the stimulation paths comprise respective capacitive elements, a capacitance ratio of which dictating, at least in part, an amplitude ratio of the positive and negative currents, wherein periodic alternative activation of the stimulation paths provides the sequential bipolar pulse stimulation. In another example, each path comprises a respective charging element and a respective activation switch, wherein each respective charging element is charged by the voltage supply and discharged upon activation of the respective activation switch to generate positive and negative current pulses respectively, such that a pulse rise time of the positive and negative current pulses is predominantly dictated by a switching speed of each respective switch. Systems and uses for these devices, and FES in general, are also described.
Owner:UNIV HEALTH NETWORK

Transmission line, and leaky-wave antenna multiplexing device and beam scanning method thereof

The invention discloses a transmission line, a leaky-wave antenna multiplexing device and a beam scanning method thereof. The device comprises a dielectric substrate, a metal strip and a metal floorboard positioned on the front and back surfaces of the dielectric substrate, and periodically alternatively arranged capacitors and variable capacitance diodes for connecting the metal floorboard and the metal strip via the through holes. The metal strip comprises gradient microstrip line structures at two ends and an artificial surface plasmon structure positioned therebetween. When the capacitance value of the variable capacitance diode is identical with that of the fixed capacitor, the surface impedance of the device is identical, and thus the function of the transmission line is achieved; when the capacitance value of the variable capacitance diode is not identical with that of the fixed capacitor, the surface impedance of the device is periodically modulated, and thus the radiation function of the leaky-wave antenna is achieved. Voltage is used as a regulation means, and fixed frequency beam scanning can be achieved along with the change of the voltage; the device is simple to manufacture, convenient to operate and prone to integrate; only a photoetching step is needed, so that cost is saved, and machining errors caused by a multi-layer structure are avoided.
Owner:SOUTHEAST UNIV

Liquid crystal display device with switchable viewing angle, and viewing angle switching method

ActiveCN107820581ANot easily polarizedSwitch freely and easilyStatic indicating devicesNon-linear opticsPeriodic alternatingLiquid-crystal display
A liquid crystal display device with a switchable viewing angle, and a viewing angle switching method. The liquid crystal display device comprises a display panel (20), wherein the display panel (20)comprises a first substrate (21), a second substrate (22) arranged opposite the first substrate (21), and a liquid crystal layer (23) located between the first substrate (21) and the second substrate(22); a viewing angle control electrode (215) is arranged on the first substrate (21), and a common electrode (225) and a pixel electrode (227) are arranged on the second substrate (22); the display panel (20) may be switched between a wide viewing angle mode and a narrow viewing angle mode. The liquid crystal display device also comprises a display control module (33) and a voltage output module(34), wherein in the wide viewing angle mode, the screen refresh frequency of the display panel (20) is the same as a data input frequency at which screen data is input to the display control module (33), and the voltage output module (34) outputs a direct-current voltage to the viewing angle control electrode (215); and in the narrow viewing angle mode, the screen refresh frequency of the displaypanel (20) is twice or quadruple the data input frequency at which the screen data is input to the display control module (33), and the voltage output module (34) outputs a periodic alternating-current voltage to the viewing angle control electrode (215).
Owner:KUSN INFOVISION OPTOELECTRONICS

Light-emitting diode (LED) with omnidirectional reflector and manufacturing method of LED

The invention discloses a gallium nitride-based light-emitting diode (LED) with an omnidirectional reflector and a manufacturing method of the gallium nitride-based LED. The gallium nitride-based LED with the omnidirectional reflector comprises a sapphire substrate and a gallium nitride-based epitaxial lamination, wherein the gallium nitride-based epitaxial lamination is formed on a first surface of the sapphire substrate; the gallium nitride-based epitaxial lamination comprises an N-type gallium nitride-based epitaxial layer, a P-type gallium nitride-based epitaxial layer and a light-emitting layer located between the N-type gallium nitride-based epitaxial layer and the P-type gallium nitride-based epitaxial layer; the omnidirectional reflector is formed a second surface of the sapphire substrate, which is opposite to the first surface; and moreover, from the second surface, the back-plated omnidirectional reflector comprises a plurality of layers of diaphanous dielectric layer piles, a gallium oxide layer and a silver reflecting layer in sequence, wherein the refractive indexes of the diaphanous dielectric layer piles are periodically and alternately changed ups and downs. Through inserting the gallium oxide layer between a silver diaphanous dielectric material layer and an oxide diaphanous dielectric material layer, the problem that the adhesion between the silver diaphanous dielectric material layer and the oxide diaphanous dielectric material layer is poor is solved.
Owner:XIAMEN SANAN OPTOELECTRONICS TECH CO LTD

Al component gradually-changed N-type LED structure and preparation method thereof

An Al component gradually-changed N-type LED structure and a preparation method thereof are disclosed. The Al component gradually-changed N-type LED structure successively comprises, from bottom to top, a substrate, a nucleating layer, a buffer layer, an N-type Al<Y>In<X>Ga<1-X-Y>N layer, a multi-quantum well light-emitting layer, and a P-type GaN layer. In the N-type Al<Y>In<X>Ga<1-X-Y>N layer, X is more than or equal to 0 but less than or equal to 1, and Y is more than 0 but less than 1. An Al component in an N-type GaN layer is gradually changed. The method comprises the following steps of: (1) growing the nucleating layer on a processed substrate; (2) growing a non-doped gallium nitride buffer layer on the nucleating layer; (3) growing the N-type Al<Y>In<X>Ga<1-X-Y>N layer on the buffer layer; (4) growing the multi-quantum well light-emitting layer on the N-type Al<Y>In<X>Ga<1-X-Y>N layer, wherein the multi-quantum well light-emitting layer is formed by periodically and alternately superposed InGaN potential well layers and GaN barrier layers; and (5) growing the P-type GaN layer on the multi-quantum well light-emitting layer. An N-type region is prepared by an Al component gradually-changed mode, thereby improving electron concentration and an antistatic effect, essentially improving GaN film quality, enhancing current expansion capability, and increasing light extraction efficiency.
Owner:SHANDONG INSPUR HUAGUANG OPTOELECTRONICS

Position encoder

The invention discloses a position encoder. The position encoder comprises a stator module, and the stator module comprises an excitation coil and a receiving coil assembly; the excitation coil is used for conducting high-frequency periodic alternating-current voltage and current, and then generating an alternating electromagnetic field in the region of the stator module; the receiving coil assembly is arranged in the region of the alternating electromagnetic field which is generated by the excitation coil, and the receiving coil assembly can generate induced electromotive force; the positionencoder also comprises a rotor module, and the rotor module is used for influencing electromagnetic coupling strength between the excitation coil and the receiving coil assembly; the position encoderfurther comprises a processing module, and the processing module comprises a signal processing unit and an oscillating circuit unit; and the position encoder further comprises a shielding layer, and the shielding layer is used for shielding outside electromagnetic interference. Compared with the prior art, the position encoder has the advantages that outer interference from metal connecting wires,metal objects, specifically a signal processing module, an electronic component and the like, a motor body and the like can be shielded, so that authenticity of position signals is guaranteed and reliability of the encoder is improved; and absolute-position signals with high precision and high resolution can be provided.
Owner:赛卓电子科技(上海)股份有限公司

Gas sensing material of cuprous oxide and stannic oxide micro-nano heterogeneous medium array structure and preparing method thereof

The invention relates to a gas sensing material of cuprous oxide and stannic oxide micro-nano heterogeneous medium array structure and a preparing method thereof, and belongs to the technical field related to gas sensing materials. The structure of the gas sensing material is a film material formed by periodically alternately assembling Cu2O and SnO2 which are parallel in elongated shapes, and the film material is generated on a silicon chip substrate, a Cu2O material is stacked thickly to form a protuberance portion, and a SnO2 material is stacked thinly to form a low ebb portion. The preparing method comprises parallelly placing two copper foil electrodes on a silicon substrate, dripping electrolyte prepared by copper nitrate and stannous chloride between the electrodes, covering a cover glass, refrigerating, solidifying and applying half-sine wave voltage, and enabling Cu2O and SnO2 to precipitate periodically and alternately. The gas sensing material of the heterogeneous medium array structure has gas sensing characteristics, the sensitivity of gas sensing elements is high at a room temperature because the gas sensing material has stable ordered heterogeneous medium structure, the service life is longe, simultaneously energy is saved and the environment is protected.
Owner:JILIN UNIV

Periodic alternating current drive low-temperature plasma ignition method and system

The invention discloses a periodic alternating current drive low-temperature plasma ignition method and a periodic alternating current drive low-temperature plasma ignition device, an relates to the technical field of aerospace engine ignition, combustion and propulsion. The method comprises the following steps of: arranging an ignitor at a proper position of a combustion chamber, wherein a high voltage electrode and a low voltage electrode of the ignitor are connected with a high voltage end and a low voltage end of a low-temperature plasma power source, and a frequency controller is connected with the low-temperature plasma power source; triggering the low-temperature plasma power source and a frequency controller switch and adjusting power output parameters; adjusting control discharge frequency of the frequency controller and discharge time of each period; and providing a trigger signal to the low-temperature plasma power source by the frequency controller, discharging by the power source, and discharging to ignite according to certain frequency by the ignitor. The invention also discloses the corresponding periodic alternating current drive low-temperature plasma ignition device. The method and the device have the advantages of large-size ignition, capabilities of shortening ignition delay time, realizing high-efficiency reliable ignition in the aspects of high-altitude low-voltage supersonic speed combustion, lean burn and the like and improving the performance of an engine, industrial energy conservation and emission reduction.
Owner:PEKING UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products