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Improved AVOA based on LSSVM for wind power prediction
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作者 ZHANG Zhonglin WEI Fan +1 位作者 YAN Guanghui MA Haiyun 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期344-359,共16页
Improving the prediction accuracy of wind power is an effective means to reduce the impact of wind power on power grid.Therefore,we proposed an improved African vulture optimization algorithm(AVOA)to realize the predi... Improving the prediction accuracy of wind power is an effective means to reduce the impact of wind power on power grid.Therefore,we proposed an improved African vulture optimization algorithm(AVOA)to realize the prediction model of multi-objective optimization least squares support vector machine(LSSVM).Firstly,the original wind power time series was decomposed into a certain number of intrinsic modal components(IMFs)using variational modal decomposition(VMD).Secondly,random numbers in population initialization were replaced by Tent chaotic mapping,multi-objective LSSVM optimization was introduced by AVOA improved by elitist non-dominated sorting and crowding operator,and then each component was predicted.Finally,Tent multi-objective AVOA-LSSVM(TMOALSSVM)method was used to sum each component to obtain the final prediction result.The simulation results show that the improved AVOA based on Tent chaotic mapping,the improved non-dominated sorting algorithm with elite strategy,and the improved crowding operator are the optimal models for single-objective and multi-objective prediction.Among them,TMOALSSVM model has the smallest average error of stroke power values in four seasons,which are 0.0694,0.0545 and 0.0211,respectively.The average value of DS statistics in the four seasons is 0.9902,and the statistical value is the largest.The proposed model effectively predicts four seasons of wind power values on lateral and longitudinal precision,and faster and more accurately finds the optimal solution on the current solution space sets,which proves that the method has a certain scientific significance in the development of wind power prediction technology. 展开更多
关键词 African vulture optimization algorithm(AVOA) least squares support vector machine(LSSVM) variational mode decomposition(VMD) multi-objective prediction wind power
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传统机理式负荷动态模型结构的改进 被引量:4
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作者 段献忠 何仰赞 +1 位作者 张步涵 张德泉 《电工技术学报》 EI CSCD 北大核心 1998年第1期5-9,共5页
恒定阻抗与等效异步电动机T型电路并联,是电力系统分析计算中普遍采用的传统机理式负荷动态模型,本文简化这种模型的结构提出了新的设想,并采用带约束的最小二乘法辨识模型参数,通过算例计算检验了设想的正确性。
关键词 电力系统 最小乘二法 负荷动态模型
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我院诊疗人次和出院人次预测 被引量:7
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作者 余莉 《中国医院统计》 2003年第2期99-99,共1页
关键词 医院 诊疗人次 出院人次 预测 最小乘二法
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Geophysical data sparse reconstruction based on L0-norm minimization 被引量:6
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作者 陈国新 陈生昌 +1 位作者 王汉闯 张博 《Applied Geophysics》 SCIE CSCD 2013年第2期181-190,236,共11页
Missing data are a problem in geophysical surveys, and interpolation and reconstruction of missing data is part of the data processing and interpretation. Based on the sparseness of the geophysical data or the transfo... Missing data are a problem in geophysical surveys, and interpolation and reconstruction of missing data is part of the data processing and interpretation. Based on the sparseness of the geophysical data or the transform domain, we can improve the accuracy and stability of the reconstruction by transforming it to a sparse optimization problem. In this paper, we propose a mathematical model for the sparse reconstruction of data based on the LO-norm minimization. Furthermore, we discuss two types of the approximation algorithm for the LO- norm minimization according to the size and characteristics of the geophysical data: namely, the iteratively reweighted least-squares algorithm and the fast iterative hard thresholding algorithm. Theoretical and numerical analysis showed that applying the iteratively reweighted least-squares algorithm to the reconstruction of potential field data exploits its fast convergence rate, short calculation time, and high precision, whereas the fast iterative hard thresholding algorithm is more suitable for processing seismic data, moreover, its computational efficiency is better than that of the traditional iterative hard thresholding algorithm. 展开更多
关键词 Geophysical data sparse reconstruction LO-norm minimization iterativelyreweighted least squares fast iterative hard thresholding
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Simulation of mould filling process using smoothed particle hydrodynamics 被引量:4
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作者 何毅 周照耀 +1 位作者 曹文炅 陈维平 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2684-2692,共9页
The implementation of high pressure die casting (HPDC) filling process modeling based on smoothed particle hydrodynamics (SPH) was discussed. A new treatment of inlet boundary was established by discriminating flu... The implementation of high pressure die casting (HPDC) filling process modeling based on smoothed particle hydrodynamics (SPH) was discussed. A new treatment of inlet boundary was established by discriminating fluid particles from inlet particles. The roles of artificial viscosity and moving least squares method in the present model were compared in the handling pressure oscillation. The final model was substantiated by simulating filling process in HPDC in both two and three dimensions. The simulated results from SPH and finite difference method (FDM) were compared with the experiments. The results show the former is in a better agreement with experiments. It demonstrates the efficiency and precision of this SPH model in describing flow pattern in filling process. 展开更多
关键词 high pressure die casting (HPDC) smoothed particle hydrodynamics (SPH) filling process moving least squares method
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Identification algorithm for a kind of fractional order system 被引量:5
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作者 王振滨 曹广益 朱新坚 《Journal of Southeast University(English Edition)》 EI CAS 2004年第3期297-302,共6页
The state-space representation of linear time-invariant (LTI) fractional order systems is introduced, and a proof of their stability theory is also given. Then an efficient identification algorithm is proposed for tho... The state-space representation of linear time-invariant (LTI) fractional order systems is introduced, and a proof of their stability theory is also given. Then an efficient identification algorithm is proposed for those fractional order systems. The basic idea of the algorithm is to compute fractional derivatives and the filter simultaneously, i.e., the filtered fractional derivatives can be obtained by computing them in one step, and then system identification can be fulfilled by the least square method. The instrumental variable method is also used in the identification of fractional order systems. In this way, even if there is colored noise in the systems, the unbiased estimation of the parameters can still be obtained. Finally an example of identifying a viscoelastic system is given to show the effectiveness of the aforementioned method. 展开更多
关键词 fractional order systems state-space representation system identification fractional order Poisson filter least square method instrumental variable method
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WEIGHTED LEAST SQUARE METHOD FOR S-N CURVE FITTING 被引量:7
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作者 吉凤贤 姚卫星 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第1期53-57,共5页
An S-N curve fitting approach is proposed based on the weighted least square method, and the weights are inversely proportional to the length of mean confidence intervals of experimental data sets. The assumption coin... An S-N curve fitting approach is proposed based on the weighted least square method, and the weights are inversely proportional to the length of mean confidence intervals of experimental data sets. The assumption coincides with the physical characteristics of the fatigue life scatter. Two examples demonstrate the method. It is shown that the method has better accuracy and reasonableness compared with the usual least square method. 展开更多
关键词 fatigue test S-N curve weighted least square method confidence interval
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Approach to estimation of vehicle-road longitudinal friction coefficient 被引量:2
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作者 宋翔 李旭 +2 位作者 张为公 陈伟 徐启敏 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期310-315,共6页
According to the road adaptive requirements for the vehicle longitudinal safety assistant system an estimation method of the road longitudinal friction coefficient is proposed.The method can simultaneously be applied ... According to the road adaptive requirements for the vehicle longitudinal safety assistant system an estimation method of the road longitudinal friction coefficient is proposed.The method can simultaneously be applied to both the high and the low slip ratio conditions. Based on the simplified magic formula tire model the road longitudinal friction coefficient is preliminarily estimated by the recursive least squares method.The estimated friction coefficient and the tires model parameters are considered as extended states. The extended Kalman filter algorithm is employed to filter out the noise and adaptively adjust the tire model parameters. Then the final road longitudinal friction coefficient is accurately and robustly estimated. The Carsim simulation results show that the proposed method is better than the conventional algorithm. The road longitudinal friction coefficient can be quickly and accurately estimated under both the high and the low slip ratio conditions.The error is less than 0.1 and the response time is less than 2 s which meets the requirements of the vehicle longitudinal safety assistant system. 展开更多
关键词 road friction coefficient recursive least squares extended Kalman filter vehicle longitudinal safety assistantsystem
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Application of nonlinear partial least square in catalyst modeling 被引量:1
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作者 黄凯 罗正鸿 +1 位作者 陈丰秋 吕德伟 《Journal of Southeast University(English Edition)》 EI CAS 2004年第1期65-69,共5页
The neural network partial least square (NNPLS) method was used to establish a robust reaction model for a multi-component catalyst of methane oxidative coupling. The details, including the learning algorithm, the num... The neural network partial least square (NNPLS) method was used to establish a robust reaction model for a multi-component catalyst of methane oxidative coupling. The details, including the learning algorithm, the number of hidden units of the inner network, activation function, initialization of the network weights and the principal components, are discussed. The results show that the structural organizations of inner neural network are 1-10-5-1, 1-8-4-1, 1-8-5-1, 1-7-4-1, 1-8-4-1, 1-8-6-1, respectively. The Levenberg-Marquardt method was used in the learning algorithm, and the central sigmoidal function is the activation function. Calculation results show that four principal components are convenient in the use of the multi-component catalyst modeling of methane oxidative coupling. Therefore a robust reaction model expressed by NNPLS succeeds in correlating the relations between elements in catalyst and catalytic reaction results. Compared with the direct network modeling, NNPLS model can be adjusted by experimental data and the calculation of the model is simpler and faster than that of the direct network model. 展开更多
关键词 Learning algorithms Least squares approximations METHANE Neural networks Principal component analysis
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Method for integer ambiguity resolution in GPS network RTK 被引量:5
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作者 潘树国 王庆 +1 位作者 柯福阳 邓健 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期491-495,共5页
A method for integer ambiguity resolution in the global positioning system (GPS) multi-reference station network real time kinematic (RTK) is proposed. First, the barycenter of the triangle of reference stations f... A method for integer ambiguity resolution in the global positioning system (GPS) multi-reference station network real time kinematic (RTK) is proposed. First, the barycenter of the triangle of reference stations for ambiguity resolution is taken as a reference point. The satellite which has the largest elevation angle with the reference point is selected as a reference satellite. The parameters for constructing the weight matrix of carrier phase observation and the criteria for checking the correctness of integer ambiguity resolution of a network are obtained. Then, the wide ambiguity is calculated by a linear combination method of dualband observation. And the LI ambiguity is obtained by a nonionosphere combination method. The Kalman filter is introduced to refine the floating-point solution of ambiguity and estimate the real-time tropospheric delay. Finally, the cofactor matrix of ambiguity is de-correlated by Z-transformation to reduce the searching space of the integer ambiguity solution and improve the efficiency of the least-squares ambiguity decorrelation adjustment (LAMBDA) algorithm. The experimental results show that this method can reliably obtain the integer ambiguity solution among multi-reference stations with 40 epochs. 展开更多
关键词 network real time kinematic AMBIGUITY troposphere: reference satellite least-squares ambiguity decorrelation adjustment
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SOLSM Channel Estimation for W CDMA
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作者 董霄剑 尤肖虎 《Journal of Southeast University(English Edition)》 EI CAS 1999年第2期8-13,共6页
Estimation of Rayleigh fading channels using time multiplexed pilot symbols in W CDMA (FDD) is considered. Method of interpolation on a second order curve using the instantaneous channel estimation of two contiguous... Estimation of Rayleigh fading channels using time multiplexed pilot symbols in W CDMA (FDD) is considered. Method of interpolation on a second order curve using the instantaneous channel estimation of two contiguous slots based on least square method (SOLSM) is presented. It is demonstrated by computer simulations that the channel distortion on data symbols in a slot can be estimated effectively compared to the method using simple linear interpolation, and the performance of the Rake combiner is improved effectively especially in fast moving cases. 展开更多
关键词 third generation mobile communication W CDMA Rake receiver least square method
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Contrast between 2D inversion and 3D inversion based on 2D high-density resistivity data 被引量:2
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作者 冯德山 戴前伟 肖波 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第1期224-232,共9页
The 2D data processing adopted by the high-density resistivity method regards the geological structures as two degrees, which makes the results of the 2D data inversion only an approximate interpretation;the accuracy ... The 2D data processing adopted by the high-density resistivity method regards the geological structures as two degrees, which makes the results of the 2D data inversion only an approximate interpretation;the accuracy and effect can not meet the precise requirement of the inversion. Two typical models of the geological bodies were designed, and forward calculation was carried out using finite element method. The forward-modeled profiles were obtained. 1% Gaussian random error was added in the forward models and then 2D and 3D inversions using a high-density resistivity method were undertaken to realistically simulate field data and analyze the sensitivity of the 2D and 3D inversion algorithms to noise. Contrast between the 2D and 3D inversion results of least squares inversion shows that two inversion results of high-density resistivity method all can basically reflect the spatial position of an anomalous body. However, the 3D inversion can more effectively eliminate the influence of interference from Gaussian random error and better reflect the distribution of resistivity in the anomalous bodies. Overall, the 3D inversion was better than 2D inversion in terms of embodying anomalous body positions, morphology and resistivity properties. 展开更多
关键词 high-density resistivity method finite element method forward simulation least square inversion 2D inversion 3D inversion apparent resistivity
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Symmetric axis detection for images based on Hough algorithm 被引量:2
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作者 李晓磊 潘晋孝 +1 位作者 刘宾 陈平 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第4期342-346,共5页
To extract the symmetric axis o{ rigid target accurately, a symmetric axis detection method is proposed based on Hough algorithm. A bullet is selected as a research object. Firstly, the original image is collected and... To extract the symmetric axis o{ rigid target accurately, a symmetric axis detection method is proposed based on Hough algorithm. A bullet is selected as a research object. Firstly, the original image is collected and the characteristics of the target image are analyzed. Because the symmetric axis detection depends on the edge detection of the image, it is necessary to use relevant operators to detect the edge and get all possible edge points. Secondly, all possible symmetric axes related to all contour points acquired are determined by Hough transform, and all possible inclination angles and intercepts and their ranges are obtained. Finally, by using least squares method, when the distance between the symmetric points of the contour points from the one edge and the contour points from the other edge is the minimum, the optimal symmetric axis is got. Simulation resuits show that the proposed method can improve noise-resistance and precision of symmetric axis detection and has certain practical value. 展开更多
关键词 Hough transform syrrunetric axis least squares method
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Evaluation model for freeway incident management system 被引量:2
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作者 何锭 倪富健 杨顺新 《Journal of Southeast University(English Edition)》 EI CAS 2010年第1期126-131,共6页
In order to evaluate the general situation and find special problems of the freeway incident management system, an evaluation model is proposed. First, the expert appraisal approach is used to select the primary evalu... In order to evaluate the general situation and find special problems of the freeway incident management system, an evaluation model is proposed. First, the expert appraisal approach is used to select the primary evaluation index. As a result, 81 indices and the hierarchical structures of the index such as the object layer, the sub-object layer, the criterion layer and the index layer are determined. Then, based on the fuzzy characteristics of each index layer, the analytical hierarchy process(AHP)and the fuzzy comprehensive evaluation are applied to generate the weight and the satisfaction of the index and the criterion layers. When analyzing the relationship between the sub-object layer and the object layer, it is easy to find that the number of sub-objects is too large and sub-objects are significantly redundant. The partial least square (PLS) is proposed to solve the problems. Finally, an application example, whose result has already been accepted and employed as the indication of a new project in improving incident management, is introduced and the result verifies the feasibility and efficiency of the model. 展开更多
关键词 freeway incident management system evaluation model analytical hierarchical process fuzzy comprehensive evaluations partial least square
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A study of particles penetration in sieving process on a linear vibration screen 被引量:18
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作者 Zhanfu Li Xin Tong 《International Journal of Coal Science & Technology》 EI 2015年第4期299-305,共7页
This paper presented an investigation of particle collision and penetration using the discrete element method to understand the motion of particles and improve theoretical treatment in the sieving process. The process... This paper presented an investigation of particle collision and penetration using the discrete element method to understand the motion of particles and improve theoretical treatment in the sieving process. The process progressively was divided into looseness, stratification, collision, and penetration. Particle penetration has a direct effect on the screening performance. The penetration probability was defined, and the mathematical relationships between particle penetration and vibration parameters were established using the least squares method. To obtain the ideal penetration probability for materials the amplitude and frequency should preferably be near 3.0 mm and 25 Hz, respectively. The vibration direction angle has only a slight effect on penetration. The stage of the screening process from 0.1 to 0.7 s is the primary region for collision and penetration. This paper focused on the sieving process to more fully understand how particle collision and penetration influence the screening efficiency. 展开更多
关键词 Penetration probability COLLISION Discrete element method Sieving process
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Multi-loop Internal Model Controller Design Based on a Dynamic PLS Framework 被引量:9
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作者 胡斌 郑平友 梁军 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第2期277-285,共9页
In this paper,a multi-loop internal model control(IMC) scheme in conjunction with feed-forward strategy based on the dynamic partial least squares(DyPLS) framework is proposed.Unlike the traditional methods to decoupl... In this paper,a multi-loop internal model control(IMC) scheme in conjunction with feed-forward strategy based on the dynamic partial least squares(DyPLS) framework is proposed.Unlike the traditional methods to decouple multi-input multi-output(MIMO) systems,the DyPLS framework automatically decomposes the MIMO process into a multi-loop system in the PLS subspace in the modeling stage.The dynamic filters with identical structure are used to build the dynamic PLS model,which retains the orthogonality among the latent variables.To address the model mismatch problem,an off-line least squares method is applied to obtain a set of optimal filter parameters in each latent space.Without losing the merits of model-based control,a simple and easy-tuned IMC structure is readily carried over to the dynamic PLS control framework.In addition,by projecting the measurable disturbance into the latent subspace,a multi-loop feed-forward control is yielded to achieve better performance for disturbance rejection.Simulation results of a distillation column are used to further demonstrate this new strategy outperforms conventional control schemes in servo behavior and disturbance rejection. 展开更多
关键词 internal model controller partial least squares latent subspace servo behavior disturbance rejection
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Phase Equilibrium of Isobutanol in Supercritical CO2 被引量:5
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作者 王琳 郝小松 +1 位作者 郑岚 陈开勋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第4期642-647,共6页
Vapor-liquid phase equilibrium data including composition,densities,molar volume and equilibrium constant of isobutanol in supercritical carbon dioxide from 313.2K to 353.2K were measured in a variable-volume visual c... Vapor-liquid phase equilibrium data including composition,densities,molar volume and equilibrium constant of isobutanol in supercritical carbon dioxide from 313.2K to 353.2K were measured in a variable-volume visual cell.The properties of critical point were obtained by extrapolation.The results showed that critical temperature,critical pressure and critical compressibility factor of CO2-isobutanol system decreased with the increase of critical CO2 content.The phase equilibrium model was established by Peng-Robinson equation of state and van der Waals-2 mixing regulation,and model parameters were determined by optimization calculation of nonlinear least square method.The correlation between calculated values and the experimental data showed good agreement. 展开更多
关键词 supercritical carbon dioxide ISOBUTANOL phase equilibrium model critical property
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Study on least square modeling of heat engineering object based on typical signal response 被引量:4
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作者 齐维贵 陈烈 朱学莉 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第1期1-4,共4页
This paper proposes a kind of least square modeling method based on typical signal response to enhance modeling accuracy of heat engineering process and adapts the environment that modeling experiment conditions are l... This paper proposes a kind of least square modeling method based on typical signal response to enhance modeling accuracy of heat engineering process and adapts the environment that modeling experiment conditions are limited. The principle of this method is, under the condition of known typical pulse, step and slope signal response and model structure, to give algorithm of model parameters of identified continuous system by least square mode through derivation. The method is applied to the identification of heat exchange process for a consumer substation, and identification result obtained is compared with that of other conventional methods. After the comparison the result shows that identification accuracy is improved obviously. In addition to the good identification accuracy, this method has the characteristics such as it can identify directly continuous system model, pure lagging time, and is not sensitive to data length in the identification process. All these characteristics show that this method is simple, easy to implement and has good practicability. 展开更多
关键词 pulse response least square method heat engineering object identification
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2-D elastic wave modeling with frequency-space 25-point finite-difference operators 被引量:9
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作者 Liao Jianping Wang Huazhong Ma Zaitian 《Applied Geophysics》 SCIE CSCD 2009年第3期259-266,300,共9页
Numerical simulation in the frequency-space domain has inherent advantages, such as: it is possible to simulate wave propagation from multiple sources simultaneously; there are no cumulative errors; only the interest... Numerical simulation in the frequency-space domain has inherent advantages, such as: it is possible to simulate wave propagation from multiple sources simultaneously; there are no cumulative errors; only the interesting frequencies can be selected; and it is more suitable for wave propagation in viscoelastic media. The only obstacle to using the method is the requirement of huge computer storage. We extend the compressed format for storing the coefficient matrix. It can reduce the required computer storage dramatically. We get the optimal coefficients by least-squares method to suppress the numerical dispersion and adopt the perfectly matched layer (PML) boundary conditions to eliminate the artificial boundary reflections. Using larger grid intervals decreases computer storage requirements and provides high computational efficiency. Numerical experiments demonstrate that these means are economic and effective, providing a good basis for elastic wave imaging and inversion. 展开更多
关键词 compressed storage frequency-space domain twenty-five point finite-difference optimal coefficients PML
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Application of RLS adaptive filteringin signal de-noising 被引量:6
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作者 程学珍 徐景东 +1 位作者 卫阿盈 逄明祥 《Journal of Measurement Science and Instrumentation》 CAS 2014年第1期32-36,共5页
In view of the problem that noises are prone to be mixed in the signals,an adaptive signal de-noising system based on reursive least squares (RLS) algorithm is introduced.The principle of adaptive filtering and the ... In view of the problem that noises are prone to be mixed in the signals,an adaptive signal de-noising system based on reursive least squares (RLS) algorithm is introduced.The principle of adaptive filtering and the process flow of RLS algorithm are described.Through example simulation,simulation figures of the adaptive de-noising system are obtained.By analysis and comparison,it can be proved that RLS adaptive filtering is capable of eliminating the noises and obtaining useful signals in a relatively good manner.Therefore,the validity of this method and the rationality of this system are demonstrated. 展开更多
关键词 DE-NOISING adaptive filtering recursive least squares (RLS) algorithm
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