95results about How to "Convenience and correctness" patented technology

The invention relates to a demodulator circuit. The demodulator circuit comprises a biasing circuit, an envelope detection circuit, a comparison circuit, a shaping circuit and a control circuit, wherein the envelope detection circuit comprises a full-wave rectification circuit and a band-pass filter, the full-wave rectification circuit is used for rectifying a full-wave alternating current signal which is received by an antenna to a direct current signal, and the band-pass filter is used for performing band-pass filtering on the direct current signal to output an envelope signal within a preset bandwidth range; the comparison circuit is used for reducing amplitude of a carrier signal through voltage comparison of the envelope signal; the shaping circuit is used for extracting an ASK signal from signals which are output by the envelope detection circuit or the comparison circuit; the control circuit is used for generating a control signal according to the ASK signal so that the band-pass filter is controlled to perform discharging before the ASK signal jumps from a low level to a high level and the comparison circuit is started and the comparison circuit is controlled to be closed after the ASK signal jumps from the high level to the low level. The demodulator circuit can be excellently applied to a passive radio frequency identification (RFID) system, and the accuracy of a demodulated signal is good.

The invention provides a direct characteristic control based novel double-fed induction motor control technology, comprising the following steps: 1, giving a voltage equation with regards to the alpha axis and beta axis of a stator of a double-fed induction motor under a stationary frame; 2, based on the voltage equation given in the step 1 and with the currents of the alpha axis and beta axis of the stator and flux linkages of the alpha axis and beta axis of a rotor as state variables, putting forward a corresponding state equation observer; 3, designing a sliding mode variable structure observer based on the step 2 so as to observe the currents of the alpha axis and beta axis of the stator and the flux linkages of the alpha axis and beta axis of the rotor at the current state; 4, carrying out discretization based on the state equation put forward in the step 2, thus obtaining a prediction control equation, namely predicting the currents of the alpha axis and beta axis of the stator and the flux linkages of the alpha axis and beta axis of the rotor at next time; and 5, using the predicted currents of the alpha axis and beta axis of the stator and currents of the d axis and q axis of the stator, calculated according to a given torque and a given rotor flux linkage together to solve a characteristic equation to obtain the voltages of the alpha axis and beta axis of the stator and sending the voltages to SVPWM. The direct characteristic control based novel double-fed induction motor control technology can be applied to the field of wind power generation and the like.

The invention discloses a system and method for calculating the time lag stability upper limit based on the generalized eigenvalue and belongs to the technical field of analysis of the stability of an electric power system. The system for calculating the time lag stability upper limit based on the generalized eigenvalue comprises a data acquisition module, a time lag system processing module, a time lag upper limit solving module and a result output module, wherein the data acquisition module, the time lag system processing module, the time lag upper limit solving module and the result output module are connected in sequence. The method for calculating the time lag stability upper limit based on the generalized eigenvalue comprises the steps that network structural parameters, the frequency of an electric generator and the power angle of the electric generator are collected, wherein the network structural parameters, the frequency of the electric generator and the power angle of the electric generator are needed for establishing a time lag system state equation; the time lag system state equation is established, order reduction is conducted on a parameter matrix in the time lag system state equation, and a time lag system state equation with the order reduced is obtained; a time lag stability criterion based on an improved free weight matrix is generated; the time lag stability upper limit is solved according to the time lag stability criterion. According to the system and method for calculating the time lag stability upper limit based on the generalized eigenvalue, the conservation of time lag stability upper limit calculation can be effectively reduced, and the correctness and effectiveness are high.

The invention relates to a non-salient-pole permanent magnet synchronous motor direct characteristic control system and a control method. The control system comprises a position loop control circuit, a rotating speed loop control circuit, a stator current detection module, a sliding mode variable structure observer, a prediction control module, a characteristic control module, a time-delay module, and an inversion module, the stator current detection module is connected with a permanent magnet synchronous motor, an input terminal of the sliding mode variable structure observer is connected with the stator current detection module, the position loop control module, and the time-delay module, an output terminal of the sliding mode variable structure observer is connected with an input terminal of the prediction control module, the input terminal of the prediction control module is connected with the position loop control circuit and the time-delay module, an output terminal of the prediction control module is connected with an input terminal of the characteristic control module, the input terminal of the characteristic control module is connected with the position loop control circuit and the rotating speed loop control circuit, an output terminal of the characteristic control module is connected with the unit time-delay module and an input terminal of the inversion module, and an output terminal of the inversion module is connected with the permanent magnet synchronous motor. Compared with the prior art, the system is advantaged by more compact structure, accurate control, fast current response speed and the like.

The invention provides a method and system for processing a medical image. The method comprises the following steps that the image is read and displayed, the image is zoomed and rotated, negative film effect processing is conducted on the image, the image is cut, the grey level of the image is transformed, the contrast ratio of the image is increased, the image is displayed in the mode of a histogram, the histogram of the image is equalized, noise of the image is eliminated, the edges of the image are detected, the image is smoothed, and the image is sharpened. The system comprises a central processing unit, an image collecting module, an image processing module, a display module and a storage module, wherein the image collecting module, the image processing module, the display module and the storage module are respectively connected with the central processing unit. According to the method and system for processing the medical image, the medical image is read in and displayed, so that a series of processing is conducted on the medical image, the image processing technologies are fully used for effectively improving the image quality, diagnosis and treatment which are relative to the state of an illness and conducted by a doctor are facilitated, and the phenomena of missed diagnosis and misdiagnosis are avoided.

The invention relates to a road slope computation method based on road alignment and spectrum features and solves the problems that road slope information in existing automobile operation work condition design quite depends on GPS (global position system) signals, has large errors and cannot be applied to operation work condition design. The road slope computation method comprises the following steps: 1, acquisition of data and establishment of an original database Database; 2, data processing: data in the original database Database is underclocked, altitude values at idling moments are all set to be hidle, a traveling segment is divided into a plurality of micro-travels, and the micro-travels with a micro-travel distance smaller than a set limit value smin are combined in adjacent micro-travels; 3, computation of slope-mile i3-s3 in the micro-travels; 4, conversion of a slope-time i4-t4 sequence: slope-mile i3-s3 data computed in the step 3 in the micro-travels are combined, and the whole slope-mile i4-s4 data formed after combination is converted into slope-time i4-t4 data to be output according to mile-time s1-t1 data of a vehicle.

The invention discloses a migration data verification method for a power dispatching automation system. The migration data verification method comprises the steps of selecting a new master station and an old master station corresponding to service migration of the power dispatching automation system, selecting some to-be-verified substation in the old master station, disconnecting a normal communication channel of the to-be-verified substation and the old master station and establishing a corresponding analog substation, enabling remote control points to be selected in the new master station and the old master station for the analog substation and serve as current remote control points, sequentially issuing a remote control selection command, a remote control execution command or a remote control revocation command according to the current remote control points, collecting original data of issued commands of the current new master station and the current old master station through the analog substation, checking and comparing the original data to finish data verification of every remote control point, and finally restoring the normal communication channel of the to-be-verified substation and the old master station. The migration data verification method can guarantee migration of the power dispatching automation system between the new master station and the old master station, and has the advantages of being quick in verification speed, high in verification efficiency, good in verification accuracy, and simple and practical.

The invention discloses a synchronous broadcasting system and a synchronous broadcasting method for an advertisement machine. The system comprises a server and a plurality of advertisement machines. The server is used for obtaining heartbeat signals of the main advertisement machine and judging whether the main advertisement machine is on-line according to the heartbeat signals. If the master advertisement machine is on line, the slave advertisement machine is used for synchronizing its own clock according to the clock information of the master advertisement machine, obtaining the playing information of the master advertisement machine after the clock synchronization, and adjusting the playing process of the master advertisement machine according to the playing information; If the master advertisement machine is offline, the server is further configured to select a slave advertisement machine as a new master advertisement machine among all the slave advertisement machines and switch the original master advertisement machine to the slave advertisement machine. The invention adopts an advertisement machine to provide the reference of clock synchronization and broadcast synchronization for other advertisement machines, and switches the master-slave relationship when the master advertisement machine is dropped, so as to improve the rapidity and stability of synchronization.

The invention discloses a file downloading method based on a P2P network, an electronic device and a storage medium, wherein the method comprises the steps of: creating a scheduling window according to task information of a file to be downloaded; dividing the scheduling window into multiple segments; sending the data requests of various segments; writing received data into the corresponding segments; and, if N continuous segments at one side of the head part of the scheduling window are written with data, sliding the head part of the scheduling window to the tail part of the N segments, wherein N is a natural number satisfying the sliding condition. The scheduling window is created; segment data in the scheduling window is downloaded at first; when the multiple continuous segments at one side of the head part of the scheduling window are written with data, the scheduling window is slid, so that downloaded data has better continuity; when the downloaded data is written in a magnetic disk, a hard disk cannot frequently turn around, forward and suddenly stop; furthermore, the IO in the magnetic disk writing process can be reduced; downloaded file fragments are less; more continuous blocks exist; and thus, the file correctness is conveniently checked.

The present invention relates to an entry sheet for printed circuit board hole boring, a water-soluble lubricating resin composition used with same and a production method for the same. The entry sheet for printed circuit board hole boring, comprises: a metal thin film substrate; and a water-soluble lubricating resin layer formed on the substrate, wherein the water-soluble lubricating resin layer comprises 100 parts by weight of a water-soluble polyester resin, from 0.5 to 3 parts by weight of a vinyl chloride - vinyl acetate copolymer and from 0.5 to 3 parts by weight of a hydrogenated hydrocarbon resin. In entry sheets produced in this way, the uniformity and accuracy of the bored holes is outstanding, the force of binding onto the metal thin film is exceptional, and there is no peeling or crack generation on the surface even at low temperature.

The invention provides a biological sample pretreatment method for treating a biological sample to obtain a pretreatment sample before gas chromatography and mass spectrometer combined detection and analysis on a metabolite in the biological sample from a living organism, application thereof to metabolite detection, and a corresponding metabolite detection and analysis method. The biological sample pretreatment method comprises the following steps: 1, performing extracting treatment; 2, performing a derivative reaction: performing the derivative reaction on the extracted biological sample by using an auxiliary reagent and a derivatization reagent to obtain a derivative biological sample; 3, standardizing and removing impurities, wherein the auxiliary reagent at least comprises a strong alkaline solution and a low-temperature alcohol organic solvent; in the step 1, the strong alkaline solution is used first and then the low-temperature alcohol organic solvent is used for continuously extracting the biological sample.

The invention discloses a composite structural column filled with coral concrete inside a fiber cloth-wrapped steel pipe. The present invention is realized through the following technical scheme, which is composed of fiber cloth, steel pipe and coral concrete, wherein the steel pipe is wound with fiber cloth, and the steel pipe is filled with coral concrete. The invention improves the strength of the coral concrete through the constraint of the circular tube; through the sealing of the outer tube, the durability of the coral concrete is enhanced; through the external coating of FRP, the corrosion resistance of the steel pipe is enhanced; brittleness.

The invention provides a method of opening network data packet files quickly. The method comprises the following steps: (1) establishing a global dictionary tree by employing modulus of network data packet file types and establishing a mapping relationship between the modulus and a file module; (2) reading a plurality of bites of a file header of a to-be-processed network data packet file and thenmatching strings of the bites, if matching is successful, carrying out step (3); and (3) if the modulus length of the to-be-processed network data packet file is proper, matching a message header, and if the matching is successful, invoking a corresponding file module processing file; if the modulus length of the to-be-processed network data packet file is too short, matching the name suffix of the file, and if the matching is successful, invoking the corresponding file module processing file. By employing the method, I/O is only used once for each file to determine the file type, and the file is quickly and correctly opened.

The invention discloses a management method of a temporary storage area. The management method comprises the following steps of loading cigarette sorted by an automatic sorting system into an empty cage trolley to form a solid cage trolley; sorting standard cigarette and/or fine cigarette through the automatic sorting system according to customer orders; writing the information of cigarette in anelectronic label of the solid cage trolley through electronic label writing equipment, and sending the bound cigarette information and cage trolley information to a management and control system; allocating a free parking space for the solid cage trolley according to the cage trolley information through the management and control system, and sending the cage trolley information and the parking space information of the solid cage trolley to a hand-held terminal of a user; parking the solid cage trolley to the parking space, and changing the state information of the parking space to occupancy; reading the electronic label of the solid cage trolley through electronic label reading equipment, sending the information in the electronic label to the management and control system, and conducting warehouse-out registration; and changing the state information of the parking space to vacancy. The management method intelligently manages the temporary storage area through the management and controlsystem and the electronic label, thereby improving the working efficiency.

The embodiment of the invention discloses a method and device for obtaining a replacing cycle of a terminal device. The method provided by the embodiment of the invention comprises following steps of obtaining a first account, wherein the first account is a user account in a preset application program; obtaining a device identifier set corresponding to the first account, wherein the device identifier set comprises at least one device identifier, the device identifier is used for uniquely identifying the terminal device; obtaining a using duration respectively corresponding to each device identifier in the device identifier set; and calculating the replacing cycle of the terminal device corresponding to the first account according to the using duration respectively corresponding to each device identifier.

The invention discloses a method for extracting the fault signal feature of a mechanical device. The method comprises steps of acquiring, by a sensor, the state signals of respective components of themechanical device; performing empirical wavelet transform on the acquired state signals to obtain the modal components of signal decomposition; calculating the correlation coefficients between respective modal components and an original signal, and selecting a plurality of modal components having the highest correlation with the original signal as the optimal modal components; constructing a Hankel matrix for the optimal modal components, and then performing singular value decomposition to obtain the feature values of the optimal modal components; subjecting the feature values of the optimalmodal components to dimensionality reduction, and combining the feature values subjected to the dimensionality reduction into a fault feature vector. The method can effectively remove the noise in theoriginal signal, retains the useful features in the original signal, and provides a necessary basis for the fault diagnosis of the mechanical device.

A disclosed positioning apparatus for a tire -pressure monitoring sensor based on a scanning gun comprises a tire-pressure monitoring sensor and a data reception display; the tire-pressure monitoring sensor is installed on a vehicle tire, and the data reception display is installed in a vehicle cab, and the tire-pressure monitoring sensor is connected with the data reception display via wireless signals; the positioning apparatus also comprises a bar code only corresponding to the tire-pressure monitoring sensor and a bar code scanner capable of distinguishing the bar code; and the bar code is arranged corresponding to the position of the tire-pressure monitoring sensor, and the bar code scanner is connected with the data reception display via wireless signals. Through the bar code only corresponding to the tire-pressure monitoring sensor and the bar code scanner capable of distinguishing the bar code, the tire-pressure monitoring sensor is subjected to exclusive positioning, the positioned position is accurate, the operation professionality is low, the maintenance cost is small, and easy positioning by a detection system can be realized both when entrucking is performed or a vehicle wheel is adjusted, and great convenience is brought for plants and users.