382 results about "Fast algorithm" patented technology

An efficient audio coding device that quantizes and encodes digital audio signals with a reduced amount of computation. A spatial transform unit subjects samples of a given audio signal to a spatial transform, thus obtaining transform coefficients of the signal. With a representative value selected out of the transform coefficients of each subband, a quantization step size calculator estimates quantization noise and calculates, in an approximative way, a quantization step size of each subband from the estimated quantization noise, as well as from a masking power threshold determined from a psycho-acoustic model of the human auditory system. A quantizer then quantizes the transform coefficients, based on the calculated quantization step sizes, thereby producing quantized values of those coefficients. The quantization step sizes are also used by a scalefactor calculator to calculate common and individual scalefactors. A coder encodes at least one of the quantized values, common scalefactor, and individual scalefactors.

An efficient simulation system of quantum algorithm gates for classical computers with a Von Neumann architecture is described. In one embodiment, a Quantum Algorithm is solved using an algorithmic-based approach, wherein matrix elements of the quantum gate are calculated on demand. In one embodiment, a problem-oriented approach to implementing Grover's algorithm is provided with a termination condition determined by observation of Shannon minimum entropy. In one embodiment, a Quantum Control Algorithm is solved by using a reduced number of quantum operations.

A selectively marked contact lens having, in one aspect, marks in an optical zone region on a surface thereof and, in another aspect, different marks outside an optical zone region of the lens, for an in-vivo lens. With the lens in-vivo, the subject's eye is illuminated and the lens is imaged. A fast algorithm is used to determine the mark coordinates in relation to a measured pupil coordinate to determine position and / or orientation of the contact lens. A wavefront aberration measurement can also be obtained simultaneously with the contact lens position measurement, as well as pupil size. A fast algorithm provides for online measurements; i.e., at a repetition rate of 10 Hz or greater, over a selected time interval. Blinking periods are determined and anomalous lens position and / or wavefront information is discarded. A most frequently occurring wavefront and / or contact lens position / orientation is determined over the selected time interval.

The invention discloses a fast image splicing method based on an improved SURF algorithm. An existing corner extraction method and an existing corner feature description method are improved, mismatching of extracted corners is eliminated, and multiple images can be spliced fast. At first, an improved FAST algorithm is adopted for increasing the extracted corners, the operation speed of the FAST algorithm for extracting the corners is high, and after the improvement is carried out, the stability is good; secondly, the combination of SURF description and LBP description is adopted for describing the corner feature, and in this way, the speed for matching the corners can also be increased; then an RANSAC method is adopted for eliminating mismatching, accuracy is improved, and a more accurate transformation matrix is obtained, so that fast splicing is carried out; finally, according to obtained matching point pairs, parameters for transforming images to be spliced into reference images are calculated, and a slow-in and slow-out method is adopted for finishing image splicing.

The invention discloses a high-dynamic weak-signal rapid capture method for a direct sequence spread spectrum system, belonging to the field of radio communication. Because a spread spectrum carrier has a chirp signal characteristic under the condition of high-dynamic motion (high-speed and high-acceleration), the high-dynamic weak-signal rapid capture method comprises the steps of: firstly, carrying out carrier Doppler frequency compensation by using a time frequency focusing characteristic of fractional order Fourier transform; secondly, carrying out incoherent accumulation on a spread frequency signal by using an order resolving capacity of the fractional order Fourier transform; and finally, carrying out capture judgment on the signal in an order Fourier domain by using a constant false alarm rate detection technology. According to the invention, the difficulty of incapability of long-time coherent accumulation under the high-dynamic condition in the traditional Fourier transform based rapid capture method is solved; and under the condition of high dynamicity and low signal to noise ratio, the signal to noise ratio is effectively increased and the signal capture time is shortened. In addition, a rapid algorithm exists in the invention and is easy to realize on the engineering in real time.

A new vehicle target identification feature extraction based on a new profile comprises an overall shape information, local statistical information and direction information compound identification feature. It puts forward a composite dual valve value identification method with quick algorithm. It uses C-Mean dynamic clustering and ternary tree principle to form an optimized matching sequence to greatly improve the identification efficiency and speed. It can be widely used in remote image identification, remote monitoring, intelligent traffic management, military scout, and so on.

The present invention includes a fast algorithm to compute the pre-equalized waveform for simultaneous compensation of the self-phase modulation and chromatic dispersion experienced by a high-speed optical signal, e.g., at 10 Gb / s, and shows that it is used for an automatic self-adapting pre-equalization when the knowledge on transmission link details is inaccurate or incomplete.

An efficient audio coding device that quantizes and encodes digital audio signals with a reduced amount of computation. A spatial transform unit subjects samples of a given audio signal to a spatial transform, thus obtaining transform coefficients of the signal. With a representative value selected out of the transform coefficients of each subband, a quantization step size calculator estimates quantization noise and calculates, in an approximative way, a quantization step size of each subband from the estimated quantization noise, as well as from a masking power threshold determined from a psycho-acoustic model of the human auditory system. A quantizer then quantizes the transform coefficients, based on the calculated quantization step sizes, thereby producing quantized values of those coefficients. The quantization step sizes are also used by a scalefactor calculator to calculate common and individual scalefactors. A coder encodes at least one of the quantized values, common scalefactor, and individual scalefactors.

The invention discloses a non-local image denoising method based on low rank restoration. The method comprises the steps of (1) collecting an image, (2) carrying out gray transformation on the collected image, (3) establishing a three-dimensional similarity matrix through the global search of a similar pixel block for the image which is subjected to gray transformation, then carrying out hard threshold filtering on the discrete cosine transform and Hadamard transform coefficients of the three-dimensional matrix is carried out, obtaining the initial estimation of the similar pixel block with the removal of partial noise, and improving the matching accuracy of the similar pixel block with low rank restoration denoising while removing a large part of noise, and (4) with transform domain filtering as prior knowledge, searching a similar pixel block in a search area for an initially denoised reference pixel block, then forming the similarity matrix by using a similarity block corresponding to an original image, carrying out low rank matrix decomposition on the similarity matrix, effectively separating noise and a signal, and obtaining a final denoised image. The method has the advantages of a simple and fast algorithm, a high signal-to-noise ratio and good consistency and is especially suitable for the requirements of high quality noise reduction of large-scale images.

The present invention provides a method and apparatus which extracts flat data from a hierarchically related representation of a circuit, such as a netlist. The apparatus and method identifies unique cell elements by a cell instance identifier and determines flat data associated with those elements. When a previously encountered cell instance which has flat data stored describing that element is selected, higher level flat data which has been stored as the apparatus traverses the representation is appended to the stored flat data for the selected element. In this manner, an optimum flat data path to all elements, nets and components is created without a need for re-scanning previously encountered cell instances.

The invention discloses a method for restoring an MTFC remote sensing image, in particular an improved MTFC algorithm, and provides a rapid MTFC algorithm which combines a restoration algorithm based on a point spread function PSF. In a mode of constructing an MTF curve through the method, the downtrend of the MTF curve is adjusted through index; an MTF value in nyquist frequency is raised to about 0.5 so as to ensure that no large noise is brought; the rapid MTFC algorithm combines the advantages of the MTFC algorithm and the PSF restoration algorithm based on the point spread function PSF; the MTF curve is constructed through the MTFC algorithm; the point spread function PSF is estimated; the PSF algorithm is used to realize restoration; and the difference between the rapid algorithm and the restoration algorithm based on the point spread function PSF lies in the establishment of the PSF. The aim of the method is to improve definition of the image, strengthen the texture detail of the image, improve the quality of the image and increase no noise at the same time; and the processing speed and the processing effect can meet the requirement of batch production.

The invention discloses an unmanned aerial vehicle energy efficiency maximization resource distribution scheme based on a physical layer safety technology, so that the purpose of maximizing the safetycapacity of the ground users is achieved. The method comprises the following steps: 1, setting parameters and initializing the parameters; 2, calculating the transmission power Pi [n] corresponding to the nth moment on the basis of the flight trajectory qi [n] of the given ith iteration; 3, updating the multiplier lambda i by using a sub-gradient iteration method according to the transmission power Pi [n]; 4, judging the average sending power constraint to obtain the sending power Pi [n] of the ith iteration; 5, utilizing the transmission power Pi [n] obtained by iteration, and calculating the parameter optimization function S (zeta i) by means of a convex optimization algorithm to obtain a flight trajectory qi [n]; 6, judging the parameter optimization function S (zeta i), judging whether the iteration stopping condition is met or not, and if the iteration stopping condition is met, the iteration stopping condition is judged, obtaining the optimal transmission power po [n] and the flight trajectory qo [n] under the optimal energy efficiency, otherwise, continuing to circulate until the condition is met. The method has the advantages of being capable of guaranteeing safe transmission of information, fast algorithm convergence, easy implementation, and can be used for wireless communication.

The invention relates to the field of computer technology, and provides an image matching method, a device, a computer device and a storage medium. The image matching method comprises the following steps: a finger vein image to be detected is obtained and grayscale processing is performed to obtain a grayscale image; a fast algorithm is used to extract the feature points of finger vein veins in gray-scale images; a sift algorithm is used to process the feature points, and the eigenvectors of each feature point are obtained; for each feature point, the cosine value between the feature vector ofthe feature point and the feature vector of each legal feature point in the legal image is calculated; if the cosine value is less than the preset cosine threshold value, the feature point of the cosine value is confirmed as the matching point; and if the cosine value is less than the preset cosine threshold value, the feature point is confirmed as the matching point; if the number of matching points is greater than the preset threshold value, it is confirmed that the finger vein image to be detected matches the legal image. The technical proposal of the invention realizes the accurate identification and matching of finger vein patterns, thereby effectively improving the accuracy of finger vein pattern matching.

The invention discloses an optimal two-vector combination-based model predictive control method and system. The method is applied to a permanent-magnet synchronous motor control system driven by a three-phase two-level inverter. A model predictive current control strategy is adopted, all two-vector combinations and resultant vector sets obtained under action time are considered at the same time, and a cost function is inspected and an optimal resultant vector is selected from all to-be-selected sets. In order to simplify the optimization process, an equivalent voltage equation is given, a sector transformation method is provided and to-be-selected two-vector combination sets are transformed into multiple fixed line segments; and a fast algorithm is given and partial complicated calculation is transformed to offline execution, so that the real-time calculated amount of the novel method is effectively reduced. The model predictive control method disclosed by the invention is simple in structure, small in real-time calculated amount and easy to implement; and the response speed of a motor is high, current ripples and distortion are small, the switching frequency is low and the dynamic and static performance of the system is excellent.

A simple and fast algorithm for multi-dimensional packet classification by solving the best matching filter problem. The substantial part of the algorithm includes the search of filters being concurrently stabbed by the packet using a KD-tree data structure. Another aspect of the present invention includes the classification of the packet according to its destination address using a second data-structure which preferably consists of a one dimensional segment tree. In a preferred embodiment of the present invention, the packet is first classified according to its protocol type, then the packet is classified according to its destination address using a one dimensional segment tree data structure, and finally, a 6 dimension KD-tree is used to find the filters being stabbed by the remaining 3 parameters of the packet. Among the filters, which comply with the packet, the filter which applies to the packet is the filter with the highest pre-determined priority. Theoretical analysis predicts and experimental results verify that in practice, the proposed data-structure can handle a lot of "difficult" filters quickly and efficiently.< / PTEXT>

The invention combines a wavelet lifting process and a difference process and provides an integratable fast algorithm for denoising electrocardiosignal and identifying QRS waves. The invention provides a method for denoising a weighted threshold value and solves the problem of signal distortion after denoising by using a global threshold value. The invention proposes to realize the lifting transformation of an electrocardiosignal by using a DB4 first-order derivative, avoid a wavelet lifting and re-decomposing process of the denoised signal and speed up the identification of QRS waves by combining the difference process in a DB4 wavelet lifting transformation process; meanwhile, an improved self-adaptive threshold updating method is adopted to improve the accuracy of QRS wave identification. In the invention, both the wavelet lifting process and a difference process, which are adopted, have the characteristics of high computing speed, low memory space occupation and capacity of realizing integer operation; therefore, the integrated application of the algorithm can be realized easily on the conventional hardware platform and can be realized easily in applications of computers and large processors.

The invention relates to a ground engineering target damage assessment system and method. The system comprises a weapon ammunition module, a target characteristic module, an effect calculation module,a damage assessment module and a simulation demonstration module. The effect calculation module is used for calling a damage effect fast algorithm to calculate damage result data of the engineering target under the action of the ammunition according to the received characteristic parameter data and target characteristic parameters of the weapon ammunition, and uploading a calculation result to the damage evaluation module and the simulation demonstration module. According to the invention, quick prediction and evaluation of the damage effect under different projectile using amounts can be carried out. The bullet consumption calculation and evaluation of the target under different damage levels can be carried out;. Impact schemes of different weapon types can be compared and evaluated. Anevaluation report is generated, and a platform and technical support are provided for engineering target protection, ammunition development and combat firepower planning.

A method using a fast algorithm automated analysis of time series sensor data that can find an optimal clustering value k for k-means analysis by using statistical analysis of the results of clustering for a stated maximal upper value of k.

Channel impulse response estimation employs a training sequence to enable correction for multipath and other disturbances affecting a signal during transmission via a digital wireless communication channel. High-speed packet transmission rates, with a training sequence for each packet, are made possible by training sequence construction enabling fast algorithm processing of received signals for impulse response estimation. Upon reception, a Toeplitz-type mathematical representation is constructed based on transmitted and received versions of a training sequence. The Toeplitz-type representation may then be processed by application of fast algorithms, such as Levinson-type algorithms, to determine coefficients representative of the communication channel impulse response. These coefficients, applied to an adaptive equalizer type of filter, enable correction for signal disturbances incurred in transmission. Channel impulse response estimation methods and systems are described.

The invention discloses a multi-resolution precondition method for analyzing aerial radiation and electromagnetic scattering problems in electromagnetic simulation. The method is a method for generating a multi-resolution basis function by using a geometrical mode on a laminar grid constructed in a grid aggregation mode and further generating multi-resolution preconditions, wherein the multi-resolution basis function is formed by linear combination of a classical vector triangle basis function (RWG), and can be conveniently applied to the conventional moment method electromagnetic simulation program to effectively improve the behavior of a matrix formed in the moment method electromagnetic simulation process so as to realize acceleration of the iterative solution process of a matrix equation and fulfill the purpose of accelerating the moment method electromagnetic simulation process. Meanwhile, the multi-resolution pre-processing technology can also be conveniently combined with a quick algorithm such as a quick multi-pole algorithm. The method has the advantages of short calculation time and capability of ensuring high precision of the program and low demand of a computing memory, and can effectively improve the computing efficiency of the conventional electromagnetic simulation.

The invention discloses a quick algorithm for joint resource allocation in a heterogeneous wireless network parallel multi-access system. When the joint resource allocation is performed in the heterogeneous wireless network parallel multi-access system, the bandwidth and power allocations are separated and the resource allocation is performed in turn, wherein the bandwidth allocation under the condition of equal power allocation is firstly performed; in the bandwidth allocation process, the advantage of high convergence rate of a Newton method is fully taken, thereby reducing the arithmetic complexity and increasing the arithmetic rate; and then the power allocation is performed; and if a power allocation result is a negative value, the bandwidth and the power are allocated again, thereby more fully utilizing the bandwidth and power resources as well as increasing the arithmetic efficiency and rate. By utilizing the algorithm to perform the joint resource allocation in the heterogeneous wireless network parallel multi-access system, the purpose of approaching the acquired resource allocation optimal solution to the theoretical optimum solution is achieved. The algorithm can be used for quickly allocating the joint resource in the heterogeneous wireless network parallel multi-access system.

A calculation method of sound field distribution of a phased array ultrasonic probe in flaw detection in a multilayer medium. The method comprises the steps of: S1, modifying a Rayleigh integral expression to obtain an expression of phased array sound field transmission; S2, establishing a fast algorithm of path in an arbitrary multilayer medium; and S3, calculating chip delay time and excitation delay time: S3-1, establishing a three-dimensional system of coordinates comprising a probe wafer, a wedge and a work piece; S3-2, conducting Fourier transform on a drive signal; S3-3, forming a path matrix; S3-4, calculating a point source delay time, diffusion attenuation, and reflection and transmission through each section; S3-5, calculating sound field amplitude and phase transformation generated from a target signal, and conducting inverse transformation to obtain sound field from each point source drive signal transmitting to the target calculation point; S3-6, superimposing to obtain sound field value at the target point; and S3-7, dividing units and sequentially calculating to obtain sound field distribution in the target area. The invention can effectively assist process design and defect evaluation phased array detection of complex multilayer structure.

The invention is a fast, high-accuracy Doppler frequency bias estimating method for mobile communication system, utilizing unmodulated pilot fdop to compare with other auxiliary carrier frequency and adopting two CZT transforms in order; firstly making rough frequency bias estimation and then making fine frequency bias estimation, and by organic integration of the two frequency bias estimations, on the basis of finding rough estimated pilot value, reducing the searching range of the fine frequency bias estimation and increasing frequency resolution so as to obtain higher estimation accuracy on the premise of not increasing the operating quantity, implementing frequency bias estimation with high accuracy, high efficiency and large estimating range. By fast algorithm of CZT transform, it can largely shorten frequency bias estimating time, further increases frequency-domain detecting range and frequency resolution and obtains higher frequency bias estimating accuracy. And it is a frequency bias estimating method with strong practicality, able to be integrated in corresponding mobile communication system and implement high- efficiency and high-accuracy estimation on any Doppler frequency bias.

The invention provides a method and a system for detecting and verifying a plurality of specific foreground objects in an image. The method includes that a background model is built according to dynamic changes of the distance of pixel points in the image; a foreground area is obtained by removing the background model from a current image; the foreground area is divided; and each foreground is verified whether to be a specific object of some class. The specific object can be a person or a chair and the like. The method and the system for detecting and verifying specific foreground objects achieve fast algorithm of detection, improve detection accuracy, and reduce false detection rate.

A method for rebuilding super resolution of small object on single frame satellite remote sense image includes setting up clear - drop model of on - track satellite remote sense influence, discriminating clear - drop parameter, estimating S - N ratio and calculating normalization factor, cutting said image to be superposed sub blocks by rebuilding algorithm, normalizing frequency domain and redundant wavelet domain, decorrelating de - noising operator, setting up fast algorithm of super resolution image rebuild, rebuilding sub pixel, using modulation transfer function as objective standard for evaluating resolution and quality of image.

The invention belongs to the field of pattern recognition, and particularly relates to a car logo locating and recognizing method and a system. According to the car logo locating and recognizing method and the system, car logos can be recognized. The car logo locating and recognizing method includes the steps: collecting pictures of samples of various car logos, and obtaining a template base of the car logos; adopting a fast algorithm, and extracting out a feature set of the sample picture of each car logo in the template base of the car logos; serving the feature sets as a training set, and generating a support vector machine (SVM) classifier. The method further includes the steps: collecting original images of the car logos; carrying out morphology preprocessing on the original images, and locating a candidate area of the car logos on images obtained through the morphology preprocessing; adopting the fast algorithm, and extracting out a to-be-recognized feature set of the candidate area of the car logos; adopting the SVM classifier, carrying out matching recognition on the to-be-recognized feature set, and serving a car logo which corresponds to a feature set matched with the to-be-recognized feature set as a recognition result.

The invention provides a mobile robot navigation method based on one point RANSAC and FAST algorithms. The method mainly includes that a robot adopts the FAST corner extraction algorithm for collecting surround environment information through a self-equipped camera; the one point RANSAC algorithm combined with extension Kalman filtering is adopted during a matching process for error matching remove; and obtained matching points are used for three-dimensional environment reconstruction and map creation. Aiming at a problem that the number of iterations is too large in the prior art employing the RANSAC algorithm, prior information obtained in a filtering phase is utilized fully. In this way, the number of iterations of the algorithm is reduced effectively and the algorithm robustness is guaranteed at the same time, so that feature matching is implemented. Problems that a traditional mobile robot is poor in monocular vision navigation real time performance and robustness and the number of iterations of the RANSAC algorithm is too large are solved.

A fast algorithm is presented which allows for substantially simultaneous acquisition, analysis, and display of a wavefront centroid image, referred to as online aberrometry. A method embodiment involves determination of an average, or most frequently occurring, wavefront aberration over a selected time interval, e.g., 20 sec. Online pupil diameter measurement allows analysis of wavefront aberration as a function of changing pupil size. A wavefront measuring apparatus is disclosed that supports online aberrometry.

The invention discloses a circular synthetic aperture radar imaging method, belonging to the technical field of electronic signal processing. The invention relates to a spatial remote sensing and air-to-ground observation information processing technology, in particular to an onboard circular synthetic aperture radar imaging technology. According to the imaging method, an original oblique plane echo is mapped to the ground plane by solving the inverse of a system kernel function, and the distribution of signals in a wave number domain is obtained by multiplying an azimuth frequency domain with a reference function, so that plane wave approximation is avoided, the problem that the size of an imaging area of the traditional polar format algorithm is limited can be solved, and the imaging of a large imaging scene can be realized; pseudo-polar coordinates are used for replacing rectangular coordinates as an intermediate interpolation transition matrix, and the distribution density characteristic of the signals in the wave number domain is considered, so that the interpolation precision is higher, the obtained image resolution is higher, and the high resolution imaging can be realized; the imaging process only involves one-dimensional interpolation, and fast algorithms such as chirp z transform (CZT) and inverse fast Fourier transform (IFFT) are adopted, so that the method has very high computational efficiency and can realize rapid imaging.