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The Successive Approximation Broyden-like Algorithm for Nonlinear Complementarity Problems 被引量:1
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作者 MAChang-feng LIANGGuo-ping 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第2期146-153,共8页
In this paper, we present a new form of successive approximation Broyden-like algorithm for nonlinear complementarity problem based on its equivalent nonsmooth equations. Under suitable conditions, we get the global c... In this paper, we present a new form of successive approximation Broyden-like algorithm for nonlinear complementarity problem based on its equivalent nonsmooth equations. Under suitable conditions, we get the global convergence on the algorithms. Some numerical results are also reported. 展开更多
关键词 nonlinear complementarity problem successive approximation Broyden-like algorithm global convergence
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The multi-motion-overlap algorithms for minimizing the time between successive scans of wafer stage
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作者 潘海鸿 Chen Lin +1 位作者 Li Xiaoqing Zhou Yunfei 《High Technology Letters》 EI CAS 2008年第3期282-288,共7页
In order to optimize the transitional time during the successive exposure scans for a step-and-scan lithography and improve the productivity in a wafer production process, an investigation of the motion trajectory pla... In order to optimize the transitional time during the successive exposure scans for a step-and-scan lithography and improve the productivity in a wafer production process, an investigation of the motion trajectory planning along the scanning direction for wafer stage was carried out. The motions of wafer stage were divided into two respective logical moves (i. e. step-move and scan-move) and the multi-motionoverlap algorithms (MMOA) were presented for optimizing the transitional time between the successive exposure scans. The conventional motion planning method, the Hazelton method and the MMOA were analyzed theoretically and simulated using MATLAB under four different exposure field sizes. The results show that the total time between two successive scans consumed by MMOA is reduced by 4.82%, 2.62%, 3.06% and 3.96%, compared with those of the conventional motion planning method; and reduced by 2.58%, 0.76%, 1.63% and 2.92%, compared with those of the Hazehon method respectively. The theoretical analyses and simulation results illuminate that the MMOA can effectively minimize the transitional step time between successive exposure scans and therefore increase the wafer fabricating productivity. 展开更多
关键词 multi-motion-overlap algorithm minimizing time successive exposure scans wafer stage step-and-scan lithography
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Gaussian fitting based optimal design of aircraft mission success space using multi-objective genetic algorithm 被引量:4
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作者 Yuan GAO Yongliang TIAN +1 位作者 Hu LIU Xue SUN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第12期3318-3330,共13页
In order to obtain the optimized aircraft design concept which meets the increasingly complex operation environment at the conceptual design stage,System-of-systems(So S)engineering must be considered.This paper propo... In order to obtain the optimized aircraft design concept which meets the increasingly complex operation environment at the conceptual design stage,System-of-systems(So S)engineering must be considered.This paper proposes a novel optimization method for the design of aircraft Mission Success Space(MSS)based on Gaussian fitting and Genetic Algorithm(GA)in the So S area.First,the concepts in the design and evaluation of MSS are summarized to introduce the Contribution to System-of-Systems(CSS)by using a conventional effectiveness index,Mission Success Rate(MSR).Then,the mathematic modelling of Gaussian fitting technique is noted as the basis of the optimization work.After that,the proposed optimal MSS design is illustrated by the multiobjective optimization process where GA acts as the search tool to find the best solution(via Pareto front).In the case study,a simulation system of penetration mission was built.The simulation results are collected and then processed by two MSS design schemes(contour and neural network)giving the initial variable space to GA optimization.Based on that,the proposed optimization method is implemented under both schemes whose optimal solutions are compared to obtain the final best design in the case study. 展开更多
关键词 EVALUATION Gaussian fitting Genetic algorithm Mission success space Neural network System-of-systems
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The Majorization Order on Monomials and Termination of the Successive Difference Substitutions
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作者 Jia XU Yong YAO 《Journal of Mathematical Research with Applications》 CSCD 2015年第2期229-236,共8页
We introduce a concept for the majorization order on monomials. With the help of this order, we derive a necessary condition on the positive termination of a general successive difference substitution algorithm (KSDS... We introduce a concept for the majorization order on monomials. With the help of this order, we derive a necessary condition on the positive termination of a general successive difference substitution algorithm (KSDS) for an input form f. 展开更多
关键词 successive difference substitution algorithm majorization order on monomials TERMINATION positive semi-definite form
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On Over-Relaxed Proximal Point Algorithms for Generalized Nonlinear Operator Equation with (A,η,m)-Monotonicity Framework
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作者 Fang Li 《International Journal of Modern Nonlinear Theory and Application》 2012年第3期67-72,共6页
In this paper, a new class of over-relaxed proximal point algorithms for solving nonlinear operator equations with (A,η,m)-monotonicity framework in Hilbert spaces is introduced and studied. Further, by using the gen... In this paper, a new class of over-relaxed proximal point algorithms for solving nonlinear operator equations with (A,η,m)-monotonicity framework in Hilbert spaces is introduced and studied. Further, by using the generalized resolvent operator technique associated with the (A,η,m)-monotone operators, the approximation solvability of the operator equation problems and the convergence of iterative sequences generated by the algorithm are discussed. Our results improve and generalize the corresponding results in the literature. 展开更多
关键词 New over-relaxed Proximal Point algorithm Nonlinear OPERATOR Equation with (A η m)-Monotonicity FRAMEWORK Generalized RESOLVENT OPERATOR Technique Solvability and Convergence
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Identification of key brain networks and functional connectivities of successful aging:A surface-based resting-state functional magnetic resonance study
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作者 Jiao-Jiao Sun Li Zhang +3 位作者 Ru-Hong Sun Xue-Zheng Gao Chun-Xia Fang Zhen-He Zhou 《World Journal of Psychiatry》 2025年第3期216-226,共11页
BACKGROUND Successful aging(SA)refers to the ability to maintain high levels of physical,cognitive,psychological,and social engagement in old age,with high cognitive function being the key to achieving SA.AIM To explo... BACKGROUND Successful aging(SA)refers to the ability to maintain high levels of physical,cognitive,psychological,and social engagement in old age,with high cognitive function being the key to achieving SA.AIM To explore the potential characteristics of the brain network and functional connectivity(FC)of SA.METHODS Twenty-six SA individuals and 47 usual aging individuals were recruited from community-dwelling elderly,which were taken the magnetic resonance imaging scan and the global cognitive function assessment by Mini Mental State Examination(MMSE).The resting state-functional magnetic resonance imaging data were preprocessed by DPABISurf,and the brain functional network was conducted by DPABINet.The support vector machine model was constructed with altered functional connectivities to evaluate the identification value of SA.RESULTS The results found that the 6 inter-network FCs of 5 brain networks were significantly altered and related to MMSE performance.The FC of the right orbital part of the middle frontal gyrus and right angular gyrus was mostly increased and positively related to MMSE score,and the FC of the right supramarginal gyrus and right temporal pole:Middle temporal gyrus was the only one decreased and negatively related to MMSE score.All 17 significantly altered FCs of SA were taken into the support vector machine model,and the area under the curve was 0.895.CONCLUSION The identification of key brain networks and FC of SA could help us better understand the brain mechanism and further explore neuroimaging biomarkers of SA. 展开更多
关键词 successful aging Resting-state functional magnetic resonance imaging Surface-based brain network analysis Functional connectivity Support vector machine algorithm
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An Improved Image Enhancement Algorithm 被引量:4
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作者 MA Jing ZOU Chengming JIN Xiaolong 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2017年第1期85-92,共8页
To solve the problems of noise,detail loss and poor contrast in the successive mean quantization transform(SMQT),a new SMQT algorithm based on Otsu algorithm is proposed.In this algorithm,we integrate the optimal th... To solve the problems of noise,detail loss and poor contrast in the successive mean quantization transform(SMQT),a new SMQT algorithm based on Otsu algorithm is proposed.In this algorithm,we integrate the optimal threshold selected by the Otsu algorithm into the SMQT algorithm,then obtain the successive mean quantization of the binary tree.By this algorithm,an enhanced image is output with a higher quality.From both subjective visual effect and objective quality evaluation,the experimental results show that the improved algorithm reduces noise,improves contrast and makes the image details more clear. 展开更多
关键词 successive mean quantization transform (SMQT) Otsu algorithm optimal threshold image enhancement
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An improved AS-SCLF decoding algorithm of polar codes based on the assigned set 被引量:5
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作者 You Wei YUAN Jianguo +1 位作者 YU Linfeng HUANG Sheng 《Optoelectronics Letters》 EI 2022年第11期694-698,共5页
An improved successive cancellation list bit-flip based on assigned set(AS-SCLF) decoding algorithm is proposed to solve the problems that the successive decoding of the successive cancellation(SC) decoder has error p... An improved successive cancellation list bit-flip based on assigned set(AS-SCLF) decoding algorithm is proposed to solve the problems that the successive decoding of the successive cancellation(SC) decoder has error propagation and the path extension of the successive cancellation list(SCL) decoder has the decision errors in the traditional cyclic redundancy check aided successive cancellation list(CA-SCL) decoding algorithm. The proposed algorithm constructs the AS firstly. The construction criterion is to use the Gaussian approximation principle to estimate the reliabilities of the polar subchannel and the error probabilities of the bits under SC decoding, and the normalized beliefs of the bits in actual decoding are obtained through the path metric under CA-SCL decoding, thus the error bits containing the SC state are identified and sorted in ascending order of the reliability. Then the SCLF decoding is performed. When the CA-SCL decoding fails for the first time, the decision results on the path of the SC state in the AS are exchanged. The simulation results show that compared with the CA-SCL decoding algorithm, the SCLF decoding algorithm based on the critical set and the decision post-processing decoding algorithm, the improved AS-SCLF decoding algorithm can improve the gain of about 0.29 dB, 0.22 dB and 0.1 dB respectively at the block error rate(BLER) of 10-4 and reduce the number of decoding at the low signal-to-noise ratio(SNR), thus the computational complexity is also reduced. 展开更多
关键词 DECODER algorithm successive
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A Novel Improved Bat Algorithm in UAV Path Planning 被引量:9
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作者 Na Lin Jiacheng Tang +1 位作者 Xianwei Li Liang Zhao 《Computers, Materials & Continua》 SCIE EI 2019年第7期323-344,共22页
Path planning algorithm is the key point to UAV path planning scenario.Many traditional path planning methods still suffer from low convergence rate and insufficient robustness.In this paper,three main methods are con... Path planning algorithm is the key point to UAV path planning scenario.Many traditional path planning methods still suffer from low convergence rate and insufficient robustness.In this paper,three main methods are contributed to solving these problems.First,the improved artificial potential field(APF)method is adopted to accelerate the convergence process of the bat’s position update.Second,the optimal success rate strategy is proposed to improve the adaptive inertia weight of bat algorithm.Third chaos strategy is proposed to avoid falling into a local optimum.Compared with standard APF and chaos strategy in UAV path planning scenarios,the improved algorithm CPFIBA(The improved artificial potential field method combined with chaotic bat algorithm,CPFIBA)significantly increases the success rate of finding suitable planning path and decrease the convergence time.Simulation results show that the proposed algorithm also has great robustness for processing with path planning problems.Meanwhile,it overcomes the shortcomings of the traditional meta-heuristic algorithms,as their convergence process is the potential to fall into a local optimum.From the simulation,we can see also obverse that the proposed CPFIBA provides better performance than BA and DEBA in problems of UAV path planning. 展开更多
关键词 UAV path planning bat algorithm the optimal success rate strategy the APF method chaos strategy
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The continuous wavelet projections algorithm: A practical spectral-feature-mining approach for crop detection 被引量:4
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作者 Xiaohu Zhao Jingcheng Zhang +3 位作者 Ruiliang Pu Zaifa Shu Weizhong He Kaihua Wu 《The Crop Journal》 SCIE CSCD 2022年第5期1264-1273,共10页
Spectroscopy can be used for detecting crop characteristics. A goal of crop spectrum analysis is to extract effective features from spectral data for establishing a detection model. An ideal spectral feature set shoul... Spectroscopy can be used for detecting crop characteristics. A goal of crop spectrum analysis is to extract effective features from spectral data for establishing a detection model. An ideal spectral feature set should have high sensitivity to target parameters but low information redundancy among features.However, feature-selection methods that satisfy both requirements are lacking. To address this issue,in this study, a novel method, the continuous wavelet projections algorithm(CWPA), was developed,which has advantages of both continuous wavelet analysis(CWA) and the successive projections algorithm(SPA) for generating optimal spectral feature set for crop detection. Three datasets collected for crop stress detection and retrieval of biochemical properties were used to validate the CWPA under both classification and regression scenarios. The CWPA generated a feature set with fewer features yet achieving accuracy comparable to or even higher than those of CWA and SPA. With only two to three features identified by CWPA, an overall accuracy of 98% in classifying tea plant stresses was achieved, and high coefficients of determination were obtained in retrieving corn leaf chlorophyll content(R^(2)= 0.8521)and equivalent water thickness(R^(2)= 0.9508). The mechanism of the CWPA ensures that the novel algorithm discovers the most sensitive features while retaining complementarity among features. Its ability to reduce the data dimension suggests its potential for crop monitoring and phenotyping with hyperspectral data. 展开更多
关键词 HYPERSPECTRAL Crop parameters Crop phenotyping Continuous wavelet analysis successive projections algorithm
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Effects of initial states on the quantum correlations in the generalized Grover search algorithm 被引量:1
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作者 Zhen-Yu Chen Tian-HuiQiu +1 位作者 Wen-Bin Zhang Hong-Yang Ma 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第8期145-151,共7页
We investigate the correlations between two qubits in the Grover search algorithm with arbitrary initial states by numerical simulation.Using a set of suitable bases,we construct the reduced density matrix and give th... We investigate the correlations between two qubits in the Grover search algorithm with arbitrary initial states by numerical simulation.Using a set of suitable bases,we construct the reduced density matrix and give the numerical expression of correlations relating to the iterations.For different initial states,we obtain the concurrence and quantum discord compared with the success probability in the algorithm.The results show that the initial states affect the correlations and the limit point of the correlations in the searching process.However,the initial states do not influence the whole cyclical trend. 展开更多
关键词 Grover search algorithm quantum correlations initial states the success probability
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Modified stochastic user-equilibrium assignment algorithm for urban rail transit under network operation
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作者 朱炜 胡昊 +1 位作者 徐瑞华 洪玲 《Journal of Central South University》 SCIE EI CAS 2013年第10期2897-2904,共8页
Based on the framework of method of successive averages(MSA), a modified stochastic user-equilibrium assignment algorithm was proposed, which can be used to calculate the passenger flow distribution of urban rail tran... Based on the framework of method of successive averages(MSA), a modified stochastic user-equilibrium assignment algorithm was proposed, which can be used to calculate the passenger flow distribution of urban rail transit(URT) under network operation. In order to describe the congestion's impact to passengers' route choices, a generalized cost function with in-vehicle congestion was set up. Building on the k-th shortest path algorithm, a method for generating choice set with time constraint was embedded, considering the characteristics of network operation. A simple but efficient route choice model, which was derived from travel surveys for URT passengers in China, was introduced to perform the stochastic network loading at each iteration in the algorithm. Initial tests on the URT network in Shanghai City show that the methodology, with rational calculation time, promises to compute more precisely the passenger flow distribution of URT under network operation, compared with those practical algorithms used in today's China. 展开更多
关键词 urban rail TRANSIT STOCHASTIC USER equilibrium ASSIGNMENT algorithm method of successive AVERAGES network operation
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An SQP algorithm for mathematical programs with nonlinear complementarity constraints
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作者 朱志斌 简金宝 张聪 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第5期659-668,共10页
In this paper, we describe a successive approximation and smooth sequential quadratic programming (SQP) method for mathematical programs with nonlinear complementarity constraints (MPCC). We introduce a class of s... In this paper, we describe a successive approximation and smooth sequential quadratic programming (SQP) method for mathematical programs with nonlinear complementarity constraints (MPCC). We introduce a class of smooth programs to approximate the MPCC. Using an 11 penalty function, the line search assures global convergence, while the superlinear convergence rate is shown under the strictly complementary and second-order sufficient conditions. Moreover, we prove that the current iterated point is an exact stationary point of the mathematical programs with equilibrium constraints (MPEC) when the algorithm terminates finitely. 展开更多
关键词 mathematical programs with equilibrium constraints (MPEC) SQP algorithm successive approximation global convergence superlinear convergence rate
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An improved construction algorithm of polar codes based on the frozen bits
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作者 YUAN Jianguo ZHANG Fengguo +1 位作者 YU Linfeng PANG Yu 《Optoelectronics Letters》 EI 2024年第3期157-162,共6页
In order to improve the problems that the minimum hamming weight(MHW) of the polar codes of the traditional Gaussian approximation(GA) construction is small and its performance is not good enough, an improved channel ... In order to improve the problems that the minimum hamming weight(MHW) of the polar codes of the traditional Gaussian approximation(GA) construction is small and its performance is not good enough, an improved channel construction algorithm of polar codes based on frozen bits is proposed by combining the construction of the Reed-Muller(RM) code to effectively increase the MHW and analyzing the correcting and checking functions of the frozen bits in the successive cancellation list(SCL) decoding. 展开更多
关键词 POLAR algorithm successive
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An Efficient Random Algorithm for Box Constrained Weighted Maximin Dispersion Problem
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作者 Jinjin Huang 《Advances in Pure Mathematics》 2019年第4期330-336,共7页
The box-constrained weighted maximin dispersion problem is to find a point in an n-dimensional box such that the minimum of the weighted Euclidean distance from given m points is maximized. In this paper, we first ref... The box-constrained weighted maximin dispersion problem is to find a point in an n-dimensional box such that the minimum of the weighted Euclidean distance from given m points is maximized. In this paper, we first reformulate the maximin dispersion problem as a non-convex quadratically constrained quadratic programming (QCQP) problem. We adopt the successive convex approximation (SCA) algorithm to solve the problem. Numerical results show that the proposed algorithm is efficient. 展开更多
关键词 MAXIMIN DISPERSION PROBLEM successive CONVEX Approximation algorithm Quadratically CONSTRAINED Quadratic Programming (QCQP)
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基于逐次变分模态分解和小波阈值的车载雷达抗干扰方法
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作者 李家强 刘浩波 +2 位作者 汪星宇 姚昌华 陈金立 《雷达科学与技术》 北大核心 2025年第4期375-386,共12页
车载毫米波雷达间交叉干扰直接影响雷达的目标探测精度和驾驶安全,针对此问题本文提出一种基于逐次变分模态分解(Successive Variational Mode Decomposition,SVMD)结合小波阈值的干扰抑制方法。首先通过PID搜索算法(PID Search Algorit... 车载毫米波雷达间交叉干扰直接影响雷达的目标探测精度和驾驶安全,针对此问题本文提出一种基于逐次变分模态分解(Successive Variational Mode Decomposition,SVMD)结合小波阈值的干扰抑制方法。首先通过PID搜索算法(PID Search Algorithm,PSA)对SVMD的最大正则化参数进行优化选择,然后利用SVMD将受扰雷达信号分解为一组本征模态函数(Intrinsic Mode Function,IMF)。接着对每个IMF依次进行小波阈值化处理以滤除各模态中的干扰,最后将各模态叠加完成信号重构,获得干扰抑制后的毫米波雷达信号。本文在PSA中加入陷阱避免算子以增加探索范围和避免局部最优,在小波阈值处理中改进了硬阈值函数以解决函数连续性差的问题。多目标场景下的仿真实验和实测实验结果表明,该方法干扰抑制效果显著,能够提高雷达的检测性能。 展开更多
关键词 毫米波雷达 逐次变分模态分解 PID搜索算法 小波阈值
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基于改进蜣螂优化算法深度混合核极限学习机的高压断路器故障诊断
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作者 范兴明 许洪华 +3 位作者 张思舜 李涛 蒋延军 张鑫 《电工技术学报》 北大核心 2025年第12期3994-4003,共10页
针对高压断路器机械故障诊断准确率偏低的问题,该文提出一种基于改进蜣螂优化算法(IDBO)优化深度混合核极限学习机(DHKELM)的故障诊断方法。首先,采用逐次变分模态分解(SVMD)对高压断路器合闸振动信号进行分解,得到若干个含本征频率的... 针对高压断路器机械故障诊断准确率偏低的问题,该文提出一种基于改进蜣螂优化算法(IDBO)优化深度混合核极限学习机(DHKELM)的故障诊断方法。首先,采用逐次变分模态分解(SVMD)对高压断路器合闸振动信号进行分解,得到若干个含本征频率的固有模态分量(IMF);其次,提取各IMF分量的功率谱熵构建特征向量矩阵,并利用t分布-随机邻域嵌入算法(t-SNE)对特征向量进行数据降维;然后,引入融合Tent混沌映射、黄金正弦策略、自适应t分布扰动策略对传统蜣螂优化算法(DBO)进行改进,并使用IDBO对DHKELM进行参数优化,完成IDBO-DHKELM高压断路器故障诊断模型的构建;最后,通过搭建模拟故障的实物断路器实验平台进行验证,结果表明,该文提出的方法在故障诊断上的准确率达到了98.33%,相较于其他故障诊断模型在多项分类评价指标上均有显著提升,为准确、可靠地诊断高压断路器机械故障提供了新方案。 展开更多
关键词 高压断路器 改进蜣螂优化算法 深度混合核极限学习机 故障诊断 逐次变分模 态分解
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基于最小二乘孪生极限学习机的水电系统发电能力预测方法
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作者 李旻 孙大雁 +3 位作者 梁志峰 过夏明 吴刚 苗树敏 《水利水电技术(中英文)》 北大核心 2025年第8期162-174,共13页
【目的】针对传统水电发电能力预测精度低、稳定性差等问题。【方法】提出了耦合模态分解、机器学习和群体智能的水电系统发电能力混合预测模型。首先,利用逐次变分模态分解法(SVMD)对原始出力序列进行分解降噪,提取出多尺度特征信号进... 【目的】针对传统水电发电能力预测精度低、稳定性差等问题。【方法】提出了耦合模态分解、机器学习和群体智能的水电系统发电能力混合预测模型。首先,利用逐次变分模态分解法(SVMD)对原始出力序列进行分解降噪,提取出多尺度特征信号进行分类建模;随后,采用最小二乘孪生极限学习机(LSTELM)对各分解信号进行预测建模,同时运用改进灰狼优化算法(IGWO)对模型参数进行优化,以提升模型的预测性能;最后对各子序列预测结果进行集成,叠加得到最终的预测结果。【结果】结果显示:所提方法在三个水电站中的预测结果精准可靠。在池潭水电站中,预见期为1 d时,所提模型在直接策略和多输入多输出策略中预测结果的纳什系数(NSE)指标较极限学习机模型分别提高了12.88%和12.11%。预见期由1 d增长至8 d时,传统方法预测结果的NSE指标由0.8840和0.8885逐渐降低到0.5735和0.5671,而本文所提两种策略预测结果分别由0.9979和0.9961逐渐降低到0.9423和0.9286。【结论】结果表明:所提模型在复杂水电系统发电能力预测中具有较强的稳定性和泛化能力,SVMD有效降低了发电能力序列的噪声影响,最小二乘法和孪生结构提升了LSTELM模型的泛化能力,SVMD-IGWO-LSTELM模型在水文特性稳定的水电站预测精度更高,在水文特性复杂的水电站预测能力略有下降但依旧保持高精度,为变化环境下水电系统发电能力预测提供有效方法。 展开更多
关键词 逐次变分模态分解法 发电出力 最小二乘孪生极限学习机 改进灰狼优化算法 影响因素
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基于IIVY-SVMD-MPE-SVM的开关柜局部放电故障识别 被引量:2
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作者 解骞 郑胜瑜 +3 位作者 刘兴华 李辉 党建 解佗 《实验技术与管理》 北大核心 2025年第4期26-36,共11页
针对开关柜局部放电故障信息表征困难及局部放电故障识别准确率低等问题,该文提出了一种基于改进常青藤算法(improved Ivy algorithm,IIVY)的自动优化连续变分模态分解(successive variational mode decomposition,SVMD)与支持向量机(su... 针对开关柜局部放电故障信息表征困难及局部放电故障识别准确率低等问题,该文提出了一种基于改进常青藤算法(improved Ivy algorithm,IIVY)的自动优化连续变分模态分解(successive variational mode decomposition,SVMD)与支持向量机(support vector machine,SVM)的模式识别算法,实现了局部放电类型的故障识别。首先,融合空间金字塔匹配混沌映射、自适应t分布与动态自适应权三种策略提出IIVY算法;其次,对局部放电原始超声波信号进行SVMD并提取多尺度排列熵(multivariate permutation entropy,MPE),建立基于IIVY-SVMD-MPE的局部放电特征提取策略,利用IIVY算法自适应地选取SVMD惩罚因子α,结合相关系数筛选出最大的三个本征模态函数(intrinsic mode function,IMF)分量提取MPE,构建多维融合特征数据集;再次,提出并建立基于IIVY-SVM的开关柜局部放电故障识别模型,利用IIVY对SVM中惩罚参数C及核参σ进行自适应寻优;最后,通过对比验证表明所建立模型综合识别率更高、在不同评价指标上表现更佳,综合识别准确率达到98.8%,有效提高了故障识别的准确性与可靠性。 展开更多
关键词 超声波 改进常青藤算法 连续变分模态分解 多尺度排列熵
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乌龙茶中水浸出物含量的近红外定量模型建立 被引量:1
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作者 任广鑫 高钰敏 +2 位作者 丁小莉 张雨茹 张正竹 《茶叶通讯》 2025年第1期93-99,共7页
水浸出物是茶叶质量评价的重要指标之一。该研究提出利用近红外光谱法结合偏最小二乘算法(Partial least squares,PLS)快速检测乌龙茶中水浸出物含量。利用近红外光谱仪采集60份乌龙茶样品的光谱信息,通过Savitzky-Golay(SG)滤波器对原... 水浸出物是茶叶质量评价的重要指标之一。该研究提出利用近红外光谱法结合偏最小二乘算法(Partial least squares,PLS)快速检测乌龙茶中水浸出物含量。利用近红外光谱仪采集60份乌龙茶样品的光谱信息,通过Savitzky-Golay(SG)滤波器对原始光谱数据进行预处理;采用连续投影算法(Successive projections algorithm,SPA)对采集的SG预处理光谱进行特征波长选择,基于SG预处理光谱和SPA法优化的特征光谱建立乌龙茶中水浸出物含量的PLS定量模型。结果显示,利用SPA法优化出14个特征波长建立SPA-PLS模型的性能最佳。在预测集中的相关系数为0.8966,预测均方根误差为0.8034%,剩余预测偏差为4.11。结果表明采用近红外光谱结合SPAPLS算法快速检测乌龙茶中水浸出物含量是可行的。 展开更多
关键词 水浸出物 近红外光谱 偏最小二乘法 连续投影算法 检测方法 乌龙茶
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