406results about How to "Reduced sampling time" patented technology

A sample image is filtered through a circumferential filter 28, an image feature amount is learned in a discrimination section 30, an image G to be searched is filtered through the circumferential filter 28 to detect a rotation invariant image feature amount for each filtered area, and each detected image feature amount is inputted into the discrimination section 30. Thereby, it is discriminated whether or not a filtering area is considered to be face image at high speed. And the dimensional number of image feature amounts is greatly reduced, so that not only the discrimination work but also the learning time of the sample image are greatly reduced.

This document describes a general system for noise reduction, as well as a specific system for Magnetic Resonance Imaging (MRI) and Nuclear Quadrupole Resonance (NQR). The general system, which is called Calculated Readout by Spectral Parallelism (CRISP), involves reconstruction and recombination of frequency-limited broadband data using separate narrowband data channels to create images or signal profiles. A multi-channel CRISP system can perform this separation using (1) frequency tuned hardware, (2) a frequency filter-bank (or equivalent), or (3) a combination of implementations (1) and (2). This system significantly reduces what we call cross-frequency noise, thereby increasing signal-to-noise-ratio (SNR). A multi-channel CRISP system applicable to MRI and NQR are described.

The invention provides a magnetic resonance image reconstruction method, comprising the following steps of acquiring undersampled k-space data; obtaining a prediction image based on the trained neuralnetwork model and the undersampled k-space data; and generating a reconstructed image based on a compressed sensing algorithm, the undersampled k-space data and the predicted image, wherein the compressed sensing algorithm includes a plurality of constraint terms, at least one of the constraint terms includes the predicted image.

A laser radar imaging device based on compressed sensing and an imaging method are disclosed. The device comprises an amplitude modulation laser light source, a beam expanding apparatus, two lenses, a DMD digital micro-mirror, an APD photoelectric detector, a high-pass filter, a multiplier, a low pass filter, two AD analog-digital converters, a control system and an image reconstruction system. After being emitted, the laser is scattered by an imaging object and then is projected to a surface of the DMD digital micro-mirror. Reflected light is focused by another lens, then is received by an APD single point detector and then is converted into an amplified voltage signal. High-pass filtering, mixing and low-pass filtering are successively performed on the voltage signal on one parallel branch and the signal penetrates into the reconstruction system after analog-digital conversion. Simultaneously, the voltage signal directly penetrates into the reconstruction system on another parallel branch after the analog-digital conversion. According to input signals of the two branches and a random matrix corresponding to a DMD control device, a certain reconstruction algorithm is combined so that the reconstruction system can complete imaging. By using the device and the method of the invention, an imaging rate and imaging quality are increased to a great extent.

The invention provides a testing method for the content of a coal seam methane sampled under a negative-pressure environment. The testing method comprises the following steps: sampling, namely carrying out in-situ measurement on the methane desorption amount; recording the final in-situ desorption amount V2; determining a methane desorption principle of a coal sample under the negative-pressure environment; carrying out lost methane amount calculation, namely calculating the loss amount V1 according to the measured methane desorption principle of the coal sample under the negative-pressure environment; carrying out residual methane amount laboratory determination, namely heating the coal sample in a sealed state and degassing in vacuum; testing the first-time degassing amount V3; crushing the coal sample by a ball grinding mill and degassing to determine the second-time degassing amount V4; carrying out gas component analysis in the degassing process; and determining the content X of the coal seam methane according to the V1, the V2, the V3 and the V4, and the weight m of the coal sample. The testing method for the content of the coal seam methane sampled under the negative-pressure environment is simple and feasible and particularly has important theoretical values and actual meanings on the desorption amount and the desorption principle of methane under the negative-pressure environment when negative-pressure pumping-out type spot sampling is carried out; the accuracy and the reliability of testing data can be greatly improved and theoretical data are provided for the coal mine safety production.

The invention discloses a depressurized extraction method for cutting through a roof or a floor of a coal seam by an abrasive water jet, which comprises the following steps: a. drilling a bedding drill hole to set depth on the roof or the floor of a coal-rock mass or a hard layer by using a drilling machine through a drill stem and a slotting drill bit; b. delivering a high-pressure abrasive water jet of which the pressure is 25-30MPa to the slotting drill bit through the drill stem, wherein the drill stem rotates in situ; forming a radial slit on the hole wall of the bedding drill hole, wherein the slit penetrates the roof or the floor of the coal-rock mass or the hard layer and a soft layer; c. enabling the drill stem to rapidly retreat for 1.5-3m so as to form a new slit; d. repeating the step c until a plurality of radial slits are formed on the bedding drill hole, and moreover, reserving a safety rock pillar of at least 5m at the slit located at the position of the orifice of the bedding drill hole at a certain distance from the orifice; e. retreating the drill stem and the slotting drill bit and sealing the hole; and f. extracting gas by a gas extraction system. The depressurized extraction method for cutting through the roof or the floor of the coal seam by the abrasive water jet has the beneficial effects that the drill hole does not have potential safety hazards and is easy to form; a hole sealing effect is good; the time of reaching the standards of extraction is short; the production efficiency is high; and the extraction is safe.

A method and system for analysis of additives in electrolysis plating solutions, using a flow management system that minimizes loss of plating solutions and decreases sampling time. The system includes at least one analysis chamber, a sampling duct connected to processing tool, a four-way valve positioned between the processing tool and the sampling duct, at least one carrier fluid duct connected to the analysis chamber, at least one actuatable multi-port valve that provides a transference platform between the sampling duct and the at least one carrier fluid duct, and a flow sensor connected to the sampling duct and positioned downstream from the at least one actuatable multi-port valve.

The invention discloses a magnetic resonance frequency and phase position double-encoding sampling method and an image reconstruction method. The sampling method comprises the following steps of (a) setting an acquisition sequence and acquiring k-space data; (b) performing N-time over-sampling to the frequency encoding gradient direction according to the acquisition sequence during acquisition and simultaneously adding frequency encoding gradient and phase position encoding gradient to control data acquisition tracks; (c) filling the data acquired in the step (b) into a k-space through an analog to digital converter (ADC) to form the k-space with an inclination factor N, wherein data points of the k-space are distributed along the frequency encoding gradient direction and the phase position encoding gradient direction in an inclined N*m rows*n columns mode, and (N-1) blank data points are filled between every two adjacent actually acquired data points in the frequency encoding direction and the phase position encoding direction, the N is an integer larger than 1, and the m and the n are positive integers. The magnetic resonance frequency and phase position double-encoding sampling method enables phase positions and frequency to be encoded simultaneously so as to control the k-space sampling tracks, enables acquisition times to be less than the acquisition s times of a traditional acquisition s mode, shortens the total acquisition time and enables reconstructed images not to have image artifacts basically.

The invention provides a drill hole arrangement structure for coal seam high-pressure waterpower slotted fracturing. Three rows of drill holes are formed in a bed plate tunnel towards a coal seam in the length direction of the bed plate tunnel. Each row of drill holes comprises a plurality of slotting drill holes and a plurality of fracturing drill holes. Trepanning points of one row of drill holes are located on a tunnel roof, and trepanning points of the other two rows of drill holes are located on tunnel sides. Two slotting drill holes are arranged between every two adjacent fracturing drill holes in each row of drill holes in a spaced mode. According to the drill hole arrangement structure, by reasonably designing the arrangement mode and the quantity of the slotting drill holes and the fracturing drill holes, while the extraction efficiency is improved, the number of the fracturing drill holes is reduced, and cost is reduced. The invention further provides a permeability-increasing method for coal seam high-pressure waterpower slotted fracturing.

The invention discloses an underwater intelligent self-adapted terrain matching method based on terrain information amount and mainly aims to solve the problems that the terrain information amount of an underwater navigation region is not sufficient or not complete so that the error of an aided navigation system is increased and the long-time accurate navigation and positioning requirements of an underwater vehicle cannot be met. The underwater intelligent self-adapted terrain matching method mainly comprises the following steps: calculating different terrain feature parameter values in the navigation region; calculating a terrain information amount aggregative index based on an intelligent method; and carrying out sampling time calculation and a self-adapted terrain matching algorithm based on a terrain information amount aggregative index value. According to the method, the problems that the terrain information amount of the underwater navigation region is not sufficient so that the error of the aided navigation system is increased and the single terrain feature index can cause the incomplete evaluation on the terrain information amount can be effectively improved; the intelligent method is used for comprehensively considering the influence of each index; the sampling time is adjusted by the terrain information amount in a self-adapted manner, the matching range is enlarged and the matching precision is improved.

The invention discloses a portable underground water fixed-depth sampling device, a sampling system and a sampling method, and belongs to the field of site pollution investigation and risk assessment.A moving blocking air bag is arranged; stagnant water at the upper end and the lower end of an underground water sampling probe in a well pipe is effectively blocked, an underground water sample at the depth where the sampling probe is located can be accurately collected, the problem that in the well washing sampling process of a traditional method, upper-layer water samples and lower-layer watersamples in the well pipe are mixed, and consequently sample dilution is caused is solved, and the concentration detection accuracy is improved. Underground water samples of different depths can be accurately collected in the same monitoring well, fixed-depth sampling is achieved, and the cost is obviously reduced. In addition, the stagnant water on the upper layer and the lower layer of the underground water sampling probe in the well pipe is effectively blocked, the well washing volume before sampling can be reduced, the sampling time is saved, the sampling efficiency is improved, the well washing wastewater generation amount is reduced, the sampling cost is further reduced, disturbance to underground water in the well pipe can be reduced, and the accuracy of detected concentration is guaranteed.

The invention discloses a compressed sensing magnetic resonance imaging method controlled by a radio-frequency pulse, and relates to the magnetic resonance imaging method. The invention provides the compressed sensing magnetic resonance imaging method controlled by the radio-frequency pulse, wherein the compressed sensing magnetic resonance imaging method controlled by the radio-frequency pulse is capable of controlling a space K to spread spectrum easily. The method includes the spectrum spreading to the space K from the radio-frequency pulse, undersampling at random and image reconstruction. In the magnetic resonance imaging, the radio-frequency pulse of linear frequency modulation is exerted along the phase encoding direction to control the energy diffusion of magnetic resonance imaging data space. The undersampling at random is carried out to the imaging data with spread spectrum, and sampling time is reduced. In terms of the undersampling data, suggested fast reconstruction algorithm is adopted to carry out sparse reconstruction to the imaging. Due to the fact that radio-frequency pulse sequence is utilized to carry out the spread spectrum of the space K, compared with space K with a shim coil, the controllable property of the spread spectrum of the space K is good. The purposes of reducing imaging time and accelerating the magnetic resonance imaging are achieved by adopting the methods of undersamping the magnetic resonance signal at random and the image reconstruction algorithm.

The invention relates to a resistance/capacitance measuring method and device thereof. The device comprises a multi-path serial resistor-capacitor module, a multi-path serial resistor-capacitor selection module, a resistor/capacitor-period conversion module and an N period time detection module, and is characterized in that: the multi-path serial resistor-capacitor module serially connects a resistor or capacitor to be detected with a corresponding determined capacitor or resistor; the multi-path serial resistor-capacitor selection module selects a line to be detected in the multi-path serial resistor-capacitor module; the resistor/capacitor-period conversion module converts the resistance-capacitance value of the selected line into a continuous pulse with period corresponding to the resistance-capacitance value and realizes power supply or capacitor charge/discharge control on the multi-path serial resistor-capacitor module; and the N period time detection module is used for detecting the time of N periods of the continuous pulse output by the resistor/capacitor-period conversion module. The device provided by the invention has very simple circuit and low cost, is widely applicable, and can shorten the sampling time by 1-2 orders of magnitude relative to a frequency conversion type circuit.

The invention discloses a sampling device and a sampling method for the gas content of insulating oil. The sampling device for the gas content of the insulating oil comprises a sampling joint, a sampling pipeline device of which one end is connected with the sampling joint, a sampler detachably connected with the other end of the sampling pipeline device, and a vacuum suction filtration device connected with the sampling pipeline device. The sampling device can improve the accuracy of a test result, is easy to operate is mounted conveniently and quickly and can realize hot-line work.

The invention discloses a fast and precise MRI (Magnetic Resonance Imaging) reconstruction method. The method comprises steps: scanning is carried out in a target visual field to obtain K space full sampling data; the K space full sampling data are sampled by using radial sampling to obtain under sampling data; the under sampling data are subjected to multi-loop data recovery to obtain an MRI image; and double-density dual-tree complex wavelet transform is used as a sparse basis, and according to the priori information of the MRI image under the double-density dual-tree complex wavelet transform, an FISTA algorithm is combined for image reconstruction. The reconstruction method can better depict image details and information, and the quality of the recovered image is improved.

The invention provides a correlation sampling based laser multi-pulse ranging system, relating to a laser ranging system. The correlation sampling based laser multi-pulse ranging system is provided with a clock control circuit module, a laser pulse transmitting module, a laser pulse receiving module and a time information processing module, wherein the clock control circuit module is provided with two clock signal output ends and is provided with a local oscillator, a first frequency divider, a second frequency divider, a first mono-stability trigger and a second mono-stability trigger; the laser pulse transmitting module is provided with a pulse driving circuit, a semiconductor laser, an opto-isolator and a collimating lens; the laser pulse receiving module is provided with an avalanche photodiode, a pre-filtering amplifying circuit, an opto-isolator and a focusing lens; and the time information processing module is provided with a first sample holding circuit and a second sample holding circuit. A sampling signal is subjected to frequency doubling, the sampling time of transmitting pulse and receiving pulse is reduced, the ranging speed is increased, the measurement precision is improved, and the correlation sampling based laser multi-pulse ranging system can solve the problem of low precision in a short-range laser ranging mode.

The present invention is characterized by a method, which simultaneously performs sterilization of the oral cavity, promotion of saliva secretion, and microsampling, at the time of saliva sampling intended for saliva tests including determination of glucose in saliva, and further provides a syringe type instrument for sampling and recovery of saliva with the use of inexpensive members for removing a salivary viscous component and recovering a salivary serous component, and a method for sampling saliva and recovering a salivary serous component with the use of the instrument.

The invention relates to a laser interference detection method for the dynamic indexes of a rotary table. The laser interference detection method is used for carrying out real-time dynamic collection and measurement on the continuous changes of angle positions of the rotary table during angle swing or angle oscillation by adopting a laser interference theory. An angle interference mirror is arranged in a light path between a laser and an angle reflecting mirror, and a laser beam is divided into two by a beam splitter mirror in the angle interference mirror; one part of the beam directly passes through the interference mirror, and is reflected back to the laser from half of the angle reflecting mirror with the angle swing; the other beam passes through the angle beam splitter mirror of the angle interference mirror, and is transmitted to the other half of the angle reflecting mirror; the angle reflecting mirror ensures that the beam passes through the interference mirror and returns to the laser; an optical path difference is formed between the two measuring beams; and the changes of the optical path difference are counted by an optical grating counter in the laser, and is converted into an angle dynamic measurement value or a dynamic angle error by computer processing. The laser interference detection method disclosed by the invention has the advantages of high detection accuracy, high sampling rate of detection, complete conformity with requirements of quantity value transmission and traceability to national reference. In the invention, the laser interferometer mainly used for detecting a numerically-controlled machine tool and a three-coordinate measuring machine is used for detecting the dynamic performance indexes of the rotary table.

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.

The utility model relates to a phase separator, comprising a sampling element, a vacuum pipeline used to vacuumize the sampling element and a blister pipeline used to input nitrogen or inert gas into the sampling element; wherein, the sampling element is composed of a sampling-separator; a separator which can be connected or disconnected with the sampling-separator is arranged under the sampling-separator, and a gas sampling bottle which can be connected or disconnected with the sampling-separator is arranged above the sampling-separator. The interior of the separator is divided into two hollow cavities: an upper hollow cavity and a lower hollow cavity; wherein, the upper hollow cavity is an eccentric structure and the volume of the lower hollow cavity is 100 to 110 percent of the volume of the sampling-separator; a blister element is arranged in the middle of the lower hollow cavity of the separator. The phase separator of the utility model has the advantages of not needing secondary separation, having fast and convenient sampling, simple structure and easy maintenance, and high separation efficiency.

The invention provides a method and a system for performing rapid diffusion tensor imaging under a compression sensing framework. The rapid diffusion tensor imaging method comprises the following steps: A, initializing a sampling mask1 which corresponds to a first diffusion gradient, and adopting a ray type sampling locus; and B, rotating the sampling mask 1 which corresponds to the first diffusion gradient by a fixed angle to obtain a sampling mask2 which corresponds to a second diffusion gradient, rotating the sampling mask2 which corresponds to the second diffusion gradient by a fixed angle in the same direction to obtain a sampling mask3 which corresponds to a third diffusion gradient, and so on till L sampling masks are obtained in total. The method and the system have the beneficial effects that under the situation of same sampling points, diffusion images of higher quality can be obtained by remodeling. In other words, less sampling points are needed in a novel scheme while the same image quality is obtained, the sampling time is shortened, and the aim of accelerating imaging is fulfilled.