82results about How to "Short sampling time" patented technology

The invention discloses a field failure on-line diagnostic method and system for a permanent magnet synchronous motor. The field failure on-line diagnostic method comprises the steps of (1) sampling a stator three-phase current signal of the motor to be detected, (2) determining a field failure characteristic frequency according to the number of poles of the permanent magnet synchronous motor to be detected, using the field failure characteristic frequency as a field failure characteristic quantity, (3) estimating the frequencies of frequency components in the stator three-phase current signal to be detected, judging whether a field failure happens or not according to whether the field failure characteristic quantity appears or not, and (4) after estimating the amplitudes of the frequency components in the stator three-phase current signal to be detected, calculating the ratios of the amplitudes of the frequency components to the amplitudes of same-frequency components within a same-current range of a motor in the normal state so as to judge the degree of severity of a field failure. The field failure on-line diagnostic system comprises the permanent magnet synchronous motor, a Hall current sensor, a signal conditioning circuit, a data acquisition circuit, a diagnosis control circuit and a display circuit. The field failure on-line diagnostic system is short in sampling time and high in anti-jamming capability, can judge field failures at different rotating speeds and under different load conditions, and is applicable to dynamic on-line monitoring.

An MRI image from spiral trajectory scanning is arranged as complementary subsets of values in time-sampled k-space. These values are Fourier transformed to produce a spatial domain image. While holding the patient stationary, the contrast information is updated at the central portion of k-space, and the peripheral portion of k-space data can be filled during the whole image acquisition. The contrast information is combined with the peripheral portion of k-space (contributing to image resolution) to construct a full k-space data and to generate a spatial image. The technique is useful for providing short time interval sampling when analyzing the take-up and fade-away of a contrast agent over time.

The invention discloses a sample-and-hold amplifier which comprises a primary sample-and-hold circuit and a secondary sample-and-hold circuit. The input positive terminal and the input negative terminal of the primary sample-and-hold circuit receive an external signal, the output positive terminal and the output negative terminal of the primary sample-and-hold circuit are coupled to the input positive terminal and the input negative terminal of the secondary sample-and-hold circuit, the primary sample-and-hold circuit is provided with a primary operational amplifier with the amplification being less than a multiple, and the secondary sample-and-hold circuit is provided with a secondary operational amplifier which realizes the amplification more than the multiple; after the external signal is sampled, held and amplified, by the primary sample-and-hold circuit and the secondary sample-and-hold circuit, the external signal is output from the output positive terminal and the output negative terminal of the secondary sample-and-hold circuit. Meanwhile, the invention discloses a sample-and-hold method. The sample-and-hold amplifier, as a basic signal processing module, is used for front end processing of the external input signal; and the sample-and-hold amplifier ensures the speed and the precision of the signal conversion with the simple structure on the premise of realizing high reliability.

The invention discloses an efficient atomized capturing sampler. The efficient atomized capturing sampler is mainly composed of a liquid storage chamber, an atomized capturing chamber and a gas-mist separation chamber, wherein the liquid storage chamber is used for containing the absorption liquid, the atomized capturing chamber converts the absorption liquid into fine mist of which the grain size has the characteristics of aerosol size, and the gas-mist separation chamber prevents the fine mist from overflowing out the sampler. The fine mist has big-enough exchange contact surface area between the gas-liquid interface, so that the fine mist can be mixed uniformly with the pollutant in the air with high efficiency, the conversation efficiency of the pollutant from gas state to liquid state is improved effectively, and the pollutant in the air of the environment can be efficiently absorbed and captured. The sampler provided by the invention is made of glassy inert material, and is interference-free and pollution-free to the obtained sample, the sampling flow is wide in range and steady, the sample acquisition time is short, the sampling efficiency is high, and the variation of outside environment factors cannot influence sampling; and moreover, the sampler is low in sampling cost, convenient for extracting the samples, and convenient for field and indoor operations.

A method for optically examining the interior of turbid media is provided. The method comprises the steps: providing broad-band light (2); spatially separating a plurality of wavelength bands (2a, 2b, . . . , 2n) contained in the broad-band light; separately modulating the plurality of wavelength bands (2a, 2b, . . . , 2n); recombining the plurality of modulated wavelength bands to a beam (11) of spectrally encoded broad-band light; illuminating a turbid medium (8) with the beam (11) of spectrally encoded broad-band light; detecting light emanating from the turbid medium (8) with a detector (9) and demodulating the detected light with a demodulator (10) to provide spectroscopic information.

The invention relates to a gas displacement and dynamic compensation sampling method in headspace analysis, comprising the following steps: (1) configuring double needles having an inlet gas carrier hole and an air outlet hole; (2) placing a sample in a sample bottle and sealing the sample; (3) inserting the double needles into the sample bottle, feeding carrier gas into the sample bottle throughthe inlet gas carrier hole, exhausting the air in the sample bottle out of the sample bottle through the air outlet hole to finish gas displacement so that the sample bottle is in a closed state; and(4) heating the sample so that a component to be tested in the sample and the partial pressure in the headspace part are balanced, pressurizing the sample with carrier gas, communicating the air outlet hole with a gas chromatograph through a feeding pipeline, wherein the sample gas flows into the feeding pipeline through the air outlet hole, the carrier gas enters into the sample bottle through the inlet gas carrier hole, and pressure in the sample bottle is stable to achieve dynamic compensation sampling. The method can ensue that the sample is automatically isolated from oxygen and not oxidized under the heating condition, and ensure short sampling time, high testing precision and favorable repeatability in the subsequent headspace extracting process.

The invention relates to a detecting tube for low concentration ammonia gas. Barium sulfate, silica gel or a mixture of the barium sulfate and the silica gel is used as a carrier; thymolsulfonphthalein and methylthymol blue are used as color reagents. The ammonia gas samples with different concentrations flow into the detecting tube; the content of the ammonia gas is determined by different colorsof the color reagents; and the detecting tube has simple structure, quick analysis, low cost and convenient to carrying, and can detect whether the content of the ammonia gas in the environmental airon-site is over-proof at the field. The application experiment shows that the detecting tube has higher sensitivity and substantially meets the requirements of national standard.

The invention provides a bird's nest identification method. The bird's nest identification method is characterized by adopting the nuclear magnetic resonance for detecting. The bird's nest identification method comprises the following steps: samples to be identified are pre-processed: the samples to be identified are grinded to fine powder; 1% of phosphoric acid water solution containing more than 10% of deuterium is added in the fine powder for implementing the water-bath heating in boiled water and centrifugating after cooling; supernate is taken into a 5 mm of nuclear magnetic tube; the nuclear magnetic tube is sealed; technical parameters are set; 1H-NMR spectrograms of the samples are acquired through a nuclear magnetic resonance spectrometer; the authenticity of bird's nests is judged through comparing the bird's nests with the 1H-NMR spectrograms of the samples to be identified. The method is simple and easily operated; the measurement of the analyzed samples has no need of exact precision; the pre-processing can be synchronously implemented for one batch of the samples; after the bird's nests are hydrolyzed, the nuclear magnetic detection is implemented for mixtures to obtain nuclear magnetic resonance hydrogen spectrums; the bird's nest identification method has the advantages of high precision, high speed, short sampling time and simple data analysis.

The invention, which belongs to the technical field of motor fault diagnosis, discloses a method for diagnosing a demagnetization fault of a permanent-magnet synchronous motor. The method comprises the following steps: carrying out current signal sampling; calculating an instantaneous value; calculating an absolute value; automatically locating a fault phase; determining a characteristic frequencyof a demagnetization fault; determining demagnetization fault occurrence; determining a severity degree of a fault; establishing a fault model for analysis; and perfecting a solution. According to the intelligent fault diagnosis method for a permanent magnet synchronous motor, no extra equipment is needed, so that the cost is reduced; the computing is done simply; the inter-turn short circuit fault can be diagnosed in real time and the fault phase can be located automatically; defects of the existing diagnosis method can be overcome and the real-time performance, effectiveness and reliabilityof the diagnosis are enhanced; the sampling time is short; the anti-interference ability is powerful; and the demagnetization fault of the permanent-magnet synchronous motor at different rotating speeds under different loads can be determined.

The invention discloses a sampling holder, which comprises a first-level sampling hold circuit and a second-level sampling hold circuit, wherein input positive and negative terminals of the first-level sampling hold circuit are connected with external signals; output positive and negative terminals of the first-level sampling hold circuit are coupled to input positive and negative terminals of the second-level sampling hold circuit; the first-level sampling hold circuit is provided with a first-level operational amplifier which realizes amplification below one multiple; the second-level sampling hold circuit is provided with a second-level operational amplifier which realizes amplification above one multiple; the external signals are sampled, held and amplified by the coordination of the first-level and second-level sampling hold circuits, and are output from output positive and negative terminals of the second-level sampling hold circuit. The invention also discloses a sampling hold method. Serving as a single processing basic module, the sampling holder is used for performing front-end processing on external input signals, and ensures the speed and precision of signal conversion by using a simple structure on the premise of realizing high reliability.

The invention discloses a constant speed sampling method and sampling device of pulverized coal. The sampling method comprises the following steps: measuring flow velocity of the pulverized coal in apulverized coal pipeline and the pulverized coal pumped into a sampling pipe by adopting an electrostatic speed measurement way, and regulating gas extraction pressure in the sampling pipe to ensure that sampling is carried out when the flow velocity of the pulverized coal is equal to that of the other pulverized coal; the sampling device comprises a negative pressure gas extraction mechanism forpumping the pulverized coal in the pulverized coal pipeline into an inner cavity of the sampling pipe, a gas extraction pipe, a sampling collection mechanism, an electrostatic speed measurement mechanism, and a PID (Proportional-Integral-Differential) adjustment mechanism, wherein a gas extractor is mounted between the gas extraction pipe and the sampling pipe; the sampling collection mechanism isused for collecting the pulverized coal which enters into the sampling pipe; the electrostatic speed measurement mechanism is used for measuring the flow velocity of the pulverized coal in the pulverized coal pipeline and the pulverized coal pumped into the sampling pipe; the PID adjustment mechanism is used for adjusting gas extraction pressure in the sampling pipe so that the flow velocity of the pulverized coal in the pulverized coal pipeline is equal to the flow velocity of the pulverized coal in the sampling pipe. The constant speed sampling method disclosed by the invention is suitablefor sampling the pulverized coal in a primary air pipe, accurate constant speed sampling is realized, sampling errors can be reduced, and sampling of the pulverized coal has representativeness; the sampling device has a simple structure and is convenient to operate.

The invention discloses a direct-current converter high-frequency impedance modeling method. The method comprises the steps of determining various harmonic paths in a DC/DC converter and a modular multilevel converter, wherein the DC/DC converter and the modular multilevel converter belong to a direct current converter; carrying out equivalence and simplification on high-frequency harmonic paths in the DC/DC converter and the modular multilevel converter according to an actual impedance parameter to obtain a constant high-frequency harmonic path; and based on the constant high-frequency harmonic path, calculating a high-frequency impedance model of each DC/DC converter and the modular multilevel converter. By using the method, on the basis of analyzing the DC/DC converter and an MMC harmonic path, reasonable equivalence and simplification are performed according to an element parameter characteristic, and a high-frequency impedance model of the converter is established. The model is not influenced by a converter control strategy and a system operation state, can accurately reflect the high-frequency impedance characteristic of the system under direct-current protection logic that the converter is not shut, and has an important reference value for configuration of direct-current protection.

The invention provides a construction method of ultrahigh performance liquid chromatography (UPLC) fingerprint of medicinal raw ginger, and belongs to the technical field of pharmaceutical analysis. The method is characterized by comprising the following steps: (1) precisely weighing about 1.25 grams of raw ginger, placing the raw ginger into a volumetric flask with a volume of 10 mL, adding methanol until the methanol reaches the scale, subjecting the volumetric flask to a supersonic treatment for 25 minutes, cooling, weighing, adding methanol to compensate the weight loss, shaking, filtering with a filter membrane with a pore size of 0.22 [mu]m, saving the filtrate for later use; (2) fingerprint preparation: adopting an ultrahigh performance liquid chromatography (UPLC) system, wherein the chromatographic column is a UPLCBEHC18 chromatographic column (2.1mm*100mm, 1.7[mu]m); acetonitrile (A)-water solution (B) is the mobile phase, gradient elution is adopted, the detection wavelength is 280 nm, the flow speed is 0.35 mL.min<-1>, and the column temperature is 35 DEG C, carrying out analysis so as to obtain UPLC fingerprint of medicinal raw ginger; (3) determination of standard fingerprint: establishing UPLC fingerprints of 17 batches of medicinal raw gingers from different production areas, and determining 16 common characteristic peaks, wherein the fingerprint characteristic of medicinal raw ginger is composed of the 16 common characteristic peaks, and can be used as the standard fingerprint of medicinal raw ginger.

The invention relates to a single-particle sampler, comprising an air inlet, a sampling head, an air pump, a flowmeter and an air outlet, wherein the air inlet is communicated with an admission nozzle of the sampling head by a vent pipe; the air outlet is communicated with an air outlet nozzle of the sampling head by the vent pipe; the flowmeter is arranged on the vent pipe; and the air outlet iscommunicated with the air pump. The single-particle sampler is characterized in that the sampling head is a single-particle sampling head and comprises the admission nozzle, the air outlet nozzle, anaccelerating chamber, a collecting chamber and a sample platform, wherein the admission nozzle is hermetically connected with the upper end of the accelerating chamber; the air outlet nozzle is hermetically connected with the lower end of the collecting chamber; the accelerating chamber is communicated with the collecting chamber by a hole; the accelerating chamber is funnel-shaped; the collecting chamber is internally provided with the sample platform; and a sampling membrane is arranged on the upper end surface of the sample platform. When being used for collecting single particles in the atmosphere, the single-particle sampler has the advantages of short sampling time, convenience in carrying, simpleness in operation, independent direct-current power supply, and the like.

The invention provides a synchronous demodulator concise in structure. The synchronous demodulator comprises a cosine generator, a sine generator, a first memory device, a MCU (microprogrammed control unit), a second memory device and a third memory device; the cosine generator and the sine generator are parallelly arranged, and the output end of the cosine generator and the output end of the sine generator are connected with the input end of the first memory device; the output end of the first memory device is connected with the first input end of the MCU; the second input end of the MCU is connected with the output end of the third memory device; the output end of the MCU is connected with the input end of the second memory device; a digital signal processor (DSP) is arranged in the MCU. The second objective of the invention is to provide a demodulating method of the synchronous demodulator, so that accuracy in demodulating can be realized. The third objective of the invention is to provide a power standard source and a control method thereof. By the application of the power standard source and the control method thereof, the control method is simple, sampling time is short, calculation is small in amount and system response is fast.

The invention discloses a tumor cell sampler for medical care, which comprises a casing, the top of the casing is movably connected with a top cover, the lower surface of the top cover is fixedly connected with a first screw, and the surface of the first screw is threaded. A movable plate is connected, the side surface of the movable plate is fixedly connected with a guide block, and a guide groove is opened at a position corresponding to the guide block in the housing, and the side of the guide block is movably connected with the inner wall of the guide groove, and the movable plate The lower surface of the housing is fixedly connected with a first spring, and the inner wall of the housing is movably connected with a needle holder, and the needle holder is fixedly connected with the bottom of the first spring, and the lower surface of the needle holder is fixedly connected with a needle tube. The surface articulation has a buckle. The present invention solves the problem that most tumor cells are sampled or sliced ​​through a syringe at present by setting a first spring, a needle seat, a needle tube, a buckle, a baffle and an air bag, the sampling process is slow, and the patient is seriously injured.

The invention discloses a triple four-quadrant rectifier simulation method which comprises the following steps: acquiring the corresponding relation between each of PWM control signals and the main circuit topological structure of a triple four-quadrant rectifier system; establishing state mathematical description of the triple four-quadrant rectifier system; acquiring a state description equation of a mathematical model of the triple four-quadrant rectifier system under control signals; and carrying out state equation judgment on the state description equation to acquire a state equation matrix and the mathematical model of the triple four-quadrant rectifier. The real-time simulation method of the invention simplifies the problem of establishing a system state space model of the triple four-quadrant rectifier into the problem of selecting relevant parameters according to the conduction conditions of switching elements, thus the invention ensures the accuracy, reduces the complexity of mathematical modeling, simplifies the realization steps, occupies few system resources, has shorter sampling time in real-time simulation, and has very high real-time property.

The invention relates to a battery state monitoring system. A battery is connected with a power utilization device. The battery state monitoring system comprises a sampling resistor, a sampling circuit, an analysis unit and a transmission unit, wherein a first end of the sampling resistor is connected with an electrode of the battery, a second end of the sampling resistor is connected with a charge-discharge interface, the sampling circuit is used for sampling a current passing through the sampling resistor and processing the current to obtain sampling data, the analysis unit is used for comparing the current sampling data with historical sampling data and analyzing a load abruptly-changing state of the current power utilization device, and the transmission unit is used for receiving the current load abruptly-changing state and sending the current load abruptly-changing state to a user terminal through a network. In the battery state monitoring system, the sampling circuit is used for sampling a charge or discharge current of the battery electrode in real time and amplifying and processing the current to obtain the sampling data, the analysis unit is used for comparing the sampling data currently sampled with pre-stored sampling data and sending a comparison result to the user terminal so as to inform a user, the battery state monitoring system is short in sampling time and accurate in sampling result, real-time monitoring and notification can be achieved, and high efficiency is achieved.