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A Note on the Spectral Radius of Weighted Signless Laplacian Matrix
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作者 Serife Büyükkose Nursah Mutlu Gülistan Kaya Gok 《Advances in Linear Algebra & Matrix Theory》 2018年第1期53-63,共11页
A weighted graph is a graph that has a numeric label associated with each edge, called the weight of edge. In many applications, the edge weights are usually represented by nonnegative integers or square matrices. The... A weighted graph is a graph that has a numeric label associated with each edge, called the weight of edge. In many applications, the edge weights are usually represented by nonnegative integers or square matrices. The weighted signless Laplacian matrix of a weighted graph is defined as the sum of adjacency matrix and degree matrix of same weighted graph. In this paper, a brief overview of the notation and concepts of weighted graphs that will be used throughout this study is given. In Section 2, the weighted signless Laplacian matrix of simple connected weighted graphs is considered, some upper bounds for the spectral radius of the weighted signless Laplacian matrix are obtained and some results on weighted and unweighted graphs are found. 展开更多
关键词 weighted Graph weighted Signless Laplacian matrix Spectral Radius
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Patch-based vehicle logo detection with patch intensity and weight matrix 被引量:3
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作者 刘海明 黄樟灿 Ahmed Mahgoub Ahmed Talab 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4679-4686,共8页
A patch-based method for detecting vehicle logos using prior knowledge is proposed.By representing the coarse region of the logo with the weight matrix of patch intensity and position,the proposed method is robust to ... A patch-based method for detecting vehicle logos using prior knowledge is proposed.By representing the coarse region of the logo with the weight matrix of patch intensity and position,the proposed method is robust to bad and complex environmental conditions.The bounding-box of the logo is extracted by a thershloding approach.Experimental results show that 93.58% location accuracy is achieved with 1100 images under various environmental conditions,indicating that the proposed method is effective and suitable for the location of vehicle logo in practical applications. 展开更多
关键词 vehicle logo detection prior knowledge gradient extraction patch intensity weight matrix background removing
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Searching high gray scale FPD scanning matrix based on PSO 被引量:2
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作者 严利民 王念 田锋 《Journal of Shanghai University(English Edition)》 CAS 2011年第3期207-211,共5页
With the increase of gray scale and flat panel display (FPD) size, subspace bitwise scanning strategy can be replaced traditional scanning method to cut down frame frequency. However, the direct searching strategy ... With the increase of gray scale and flat panel display (FPD) size, subspace bitwise scanning strategy can be replaced traditional scanning method to cut down frame frequency. However, the direct searching strategy (DSS) becomes unfeasible to obtain corresponding high gray scale scanning matrix. Thus, particle swarm optimization (PSO) is introduced to accelerate searching for high gray scale weights scanning matrix (WSM) with its parallelism and global optimization feature. Finally a WSM of 256 gray scales is found out successfully with Matlab, which both gray linearity and scanning efficiency are satisfied. 展开更多
关键词 flat panel display (FPD) gray scale scanning efficiency (SE) weights scanning matrix (WSM) particle swarm optimization (PSO)
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Spatial weight matrix in dimensionality reduction reconstruction for microelectromechanical system-based photoacoustic microscopy 被引量:1
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作者 Yuanzheng Ma Chang Lu +2 位作者 Kedi Xiong Wuyu Zhang Sihua Yang 《Visual Computing for Industry,Biomedicine,and Art》 2020年第1期247-256,共10页
A micro-electromechanical system(MEMS)scanning mirror accelerates the raster scanning of optical-resolution photoacoustic microscopy(OR-PAM).However,the nonlinear tilt angular-voltage characteristic of a MEMS mirror i... A micro-electromechanical system(MEMS)scanning mirror accelerates the raster scanning of optical-resolution photoacoustic microscopy(OR-PAM).However,the nonlinear tilt angular-voltage characteristic of a MEMS mirror introduces distortion into the maximum back-projection image.Moreover,the size of the airy disk,ultrasonic sensor properties,and thermal effects decrease the resolution.Thus,in this study,we proposed a spatial weight matrix(SWM)with a dimensionality reduction for image reconstruction.The three-layer SWM contains the invariable information of the system,which includes a spatial dependent distortion correction and 3D deconvolution.We employed an ordinal-valued Markov random field and the Harris Stephen algorithm,as well as a modified delay-and-sum method during a time reversal.The results from the experiments and a quantitative analysis demonstrate that images can be effectively reconstructed using an SWM;this is also true for severely distorted images.The index of the mutual information between the reference images and registered images was 70.33 times higher than the initial index,on average.Moreover,the peak signal-to-noise ratio was increased by 17.08%after 3D deconvolution.This accomplishment offers a practical approach to image reconstruction and a promising method to achieve a real-time distortion correction for MEMS-based OR-PAM. 展开更多
关键词 Photoacoustic microscopy Spatial weight matrix Dimensionality reduction Distortion correction Mutual information
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Optimal strategy of searching FPD weights scanning matrix using GA-PSO
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作者 严利民 顾裕灿 李建东 《Journal of Shanghai University(English Edition)》 CAS 2011年第4期292-296,共5页
This paper discusses a kind of optimal method used for searching flat panel display (FPD) scanning matrix. The method adopts bionic algorithm: genetic algorithm (GA) and particle swarm optimization (PSO) algori... This paper discusses a kind of optimal method used for searching flat panel display (FPD) scanning matrix. The method adopts bionic algorithm: genetic algorithm (GA) and particle swarm optimization (PSO) algorithm. The method using single GA is more time-consuming, and the search efficiency is low in later evolution; the PSO algorithm is easily falling into the local optimal solution and appears the premature convergent phenomenon. Hence, a hybrid approach of GAPSO is found to optimize the search for high grayscale weights scanning matrix. Finally in the acceptable time, it finds a weight scanning matrix (WSM) of 256 gray scales with Matlab, whose scanning efficiency reaches 94.73% and the linearity is very good. 展开更多
关键词 fiat panel display (FPD) weights scanning matrix (WSM) genetic algorithm (GA) particle swarm optimization (PSO) algorithm
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Research on consistency measurement and weight estimation approach of hybrid uncertain comparison matrix
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作者 Zhu Jianjun Zhu Ningning Liu Sifeng Li Tao Wang Hehua 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第6期1145-1150,共6页
The consistency measurement and weight estimation approach of the hybrid uncertain comparison matrix in the analytic hierarchy process (AHP) are studied. First, the decision-making satisfaction membership function i... The consistency measurement and weight estimation approach of the hybrid uncertain comparison matrix in the analytic hierarchy process (AHP) are studied. First, the decision-making satisfaction membership function is defined based on the decision making's allowable error. Then, the weight model based on the maximal satisfactory consistency idea is suggested, and the consistency index is put forward. Moreover, the weight distributing value model is developed to solve the decision making misleading problem since the multioptimization solutions in the former model. Finally, the weights are ranked based on the possibility degree approach to obtain the ultimate order. 展开更多
关键词 analytic hierarchy process uncertainty hybrid comparison matrix weight
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Spatial spillover effects of transport infrastructure on regional economic growth
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作者 刘南 陈远高 周庆明 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期33-39,共7页
Spatial spillover effects,either positive or negative,of transport infrastructure,highways/expressways,etc.,on regional economic growth are proposed.Using the panel data for 11 cities of Zhejiang province from 1994 to... Spatial spillover effects,either positive or negative,of transport infrastructure,highways/expressways,etc.,on regional economic growth are proposed.Using the panel data for 11 cities of Zhejiang province from 1994 to 2003,a spatial production function is applied to examine the spatial spillovers which can be generated as a positive output spillover from the transport infrastructure between neighboring cities.Some spatial weighted matrices are adopted to define different neighboring cities to measure how easily factors or economic activities can migrate between regions.The estimation results show that the output elasticity of the highway infrastructure in 11 cities are all insignificant at a 5% significance level;hence,highway infrastructure in a region cannot explain the same region's economic growth.On the other hand,the highway infrastructure of other contiguous regions has positive spillover effects on a same region's economic growth. 展开更多
关键词 transport infrastructure HIGHWAY economic growth effects of spatial spillovers spatial weighted matrix
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Control of static unstable airframes 被引量:2
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作者 Junfang Fan Defu Lin +1 位作者 Zhong Su Qing Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期1063-1071,共9页
The challenge and control problems of static unstable missiles are presented. The steady-state benefits of static instability are illustrated, while the corresponding control challenge is described both by the charact... The challenge and control problems of static unstable missiles are presented. The steady-state benefits of static instability are illustrated, while the corresponding control challenge is described both by the characteristic lag of airframe and the increment of necessary control usage. Control limitation led by unstable zero-pole pair is analyzed for preliminary design and evaluation. Linear control strategy is examined wherein two and three loop acceleration autopilots with different control usages are developed using an optimal control approach combined with frequency domain constraint. The weights selection and relation with system performance are detailed. Then the nonlinear backstepping recursive method is detailed to determine how well it is able to follow command and its engineering feasibility. The results show that a static unstable missile is controllable, while the actuator bandwidth is the crucial limited factor. There should be a compromise between overall performance and actuator payment. 展开更多
关键词 missile control static instability optimal control BACKSTEPPING weight matrix unstable zero-pole pair.
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PEMFC Fractional-order Subspace Identification Model 被引量:2
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作者 Sun Chengshuo Qi Zhidong +1 位作者 Qin Hao Shan Liang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2022年第3期151-160,共10页
A proton exchange membrane fuel cell(PEMFC)is a new type of hydrogen fuel cell that plays an indispensable role in an energy network.However,the multivariable and fractional-order characteristics of PEMFC make it diff... A proton exchange membrane fuel cell(PEMFC)is a new type of hydrogen fuel cell that plays an indispensable role in an energy network.However,the multivariable and fractional-order characteristics of PEMFC make it difficult to establish a practical model.Herein,a fractional-order subspace identification model based on the adaptive monarch butterfly optimization algorithm with opposition-based learning(ALMBO)algorithm is proposed for PEMFC.Introducing the fractional-order theory into the subspace identification method by adopting a Poisson filter for with input and output data,a weight matrix is proposed to improve the identification accuracy.Additionally,the ALMBO algorithm is employed to optimize the parameters of the Poisson filter and fractional order,which introduces an opposition-based learning strategy into the migration operator and incorporates adaptive weights to improve the optimization accuracy and prevent falling into a locally optimal solution.Finally,the PEMFC fractional-order subspace identification model is established,which can accurately describe the dynamic process of PEMFC. 展开更多
关键词 PEMFC fractional subspace identification weight matrix ALMBO
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Multi-channel signal parameters joint optimization for GNSS terminals 被引量:1
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作者 WANG Qian ZHANG Chuanding XIAN Deyong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第1期39-47,共9页
Traditional global navigation satellite system(GNSS)terminals for satellite navigation adopt independent channels to track the signals from different satellites, which results in a lack of information interaction betw... Traditional global navigation satellite system(GNSS)terminals for satellite navigation adopt independent channels to track the signals from different satellites, which results in a lack of information interaction between the channels. Inspired by the vector tracking idea, and drawing lessons from the principle that in the position domain the Taylor expanded pseudorange observations can be used for positioning via the least squares method, this paper proposes a novel least squares-based multi-channel parameter joint estimation(MPJE) method in the signal domain, which not only retains the advantages of channel fusion, but also maintains the flexibility and diversity of the localization algorithm. With achieving optimal carrier to noise ratio as the goal, the proposed method obtains the required code loop and carrier loop parameters for signal tracking in the domain of whole channels. Experimental results indicate that this method fully achieves the assistant fusion advantages of frequency lock loop(FLL), phase lock loop(PLL)and delay lock loop(DLL), making good use of the robustness and dynamic properties of the FLL and the measurement accuracy of the DLL, and is helpful for achieving stable and accurate signal tracking under weak signals and high dynamic stress environments. 展开更多
关键词 least squares method signal parameter optimization vector tracking global navigation satellite system(GNSS) weight matrix
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Shadow detection combining characters of human vision
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作者 李建锋 邹北骥 +1 位作者 李玲芝 高焕芝 《Journal of Central South University》 SCIE EI CAS 2014年第2期659-667,共9页
A shadow detection method using pulse couple neural network inspired by the characters of human visual system is proposed.More precisely,lateral inhibition of human vision and coefficient of variation are combined tog... A shadow detection method using pulse couple neural network inspired by the characters of human visual system is proposed.More precisely,lateral inhibition of human vision and coefficient of variation are combined together to improve the pulse couple neural network.Shadow detection is considered to be a shadow region segmentation problem.Experiment shows that the presented method is consistent with human vision compared to shadow detection methods based on HSV and pulse couple neural network(PCNN) by both subjective and objective assessments. 展开更多
关键词 pulse couple neural network lateral inhibition shadow detection coefficient of variation weight matrix human vision system
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Eukaryotic Promoter Recognition Using Back propagation Neural Network 被引量:1
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作者 XIONGQing WANGYuan-Qiang LIZhi-Liang 《Chinese Journal of Biomedical Engineering(English Edition)》 2004年第2期87-92,共6页
A new system is developed to recognize promoter sequences from non promoter sequences based on position weight matrix and backpropagation neural network in this paper. The system performs significantly better on the t... A new system is developed to recognize promoter sequences from non promoter sequences based on position weight matrix and backpropagation neural network in this paper. The system performs significantly better on the training set and the test set, the mean recognition rate is as high as 99% on the training set and 97% on the testing set. Experimental results demonstrate the effectiveness of the system to recognize the promoter sequences that have been trained and the promoter sequences that have not been seen previously. 展开更多
关键词 Eukaryotic promoter recognition BP neural network Position weight matrix
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Receding horizon H_∞ control for discrete-time Markovian jump linear systems
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作者 Jiwei Wen Fei Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第2期292-299,共8页
Receding horizon H∞ control scheme which can deal with both the H∞ disturbance attenuation and mean square stability is proposed for a class of discrete-time Markovian jump linear systems when minimizing a given qua... Receding horizon H∞ control scheme which can deal with both the H∞ disturbance attenuation and mean square stability is proposed for a class of discrete-time Markovian jump linear systems when minimizing a given quadratic performance criteria. First, a control law is established for jump systems based on pontryagin’s minimum principle and it can be constructed through numerical solution of iterative equations. The aim of this control strategy is to obtain an optimal control which can minimize the cost function under the worst disturbance at every sampling time. Due to the difficulty of the assurance of stability, then the above mentioned approach is improved by determining terminal weighting matrix which satisfies cost monotonicity condition. The control move which is calculated by using this type of terminal weighting matrix as boundary condition naturally guarantees the mean square stability of the closed-loop system. A sufficient condition for the existence of the terminal weighting matrix is presented in linear matrix inequality (LMI) form which can be solved efficiently by available software toolbox. Finally, a numerical example is given to illustrate the feasibility and effectiveness of the proposed method. 展开更多
关键词 Marker jump linear systems receding horizon H∞ control mean square stability terminal weighting matrix pontrya-gin's minimum principle current time jump mode.
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A combined statistical model for multiple motifs search
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作者 高丽锋 刘鑫 官山 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第12期4396-4400,共5页
Transcription factor binding sites (TFBS) play key roles in genebior 6.8 wavelet expression and regulation. They are short sequence segments with definite structure and can be recognized by the corresponding transcr... Transcription factor binding sites (TFBS) play key roles in genebior 6.8 wavelet expression and regulation. They are short sequence segments with definite structure and can be recognized by the corresponding transcription factors correctly. From the viewpoint of statistics, the candidates of TFBS should be quite different from the segments that are randomly combined together by nucleotide. This paper proposes a combined statistical model for finding over- represented short sequence segments in different kinds of data set. While the over-represented short sequence segment is described by position weight matrix, the nucleotide distribution at most sites of the segment should be far from the background nucleotide distribution. The central idea of this approach is to search for such kind of signals. This algorithm is tested on 3 data sets, including binding sites data set of cyclic AMP receptor protein in E.coli, PlantProm DB which is a non-redundant collection of proximal promoter sequences from different species, collection of the intergenic sequences of the whole genome of E.Coli. Even though the complexity of these three data sets is quite different, the results show that this model is rather general and sensible. 展开更多
关键词 transcription factor binding sites MOTIF position weight matrix
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Multi-criteria decision-making method for evaluation of investment in enhanced geothermal systems projects
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作者 Sara Raos Josipa Hranić Ivan Rajšl 《Energy and AI》 EI 2024年第3期143-167,共25页
Deep geothermal energy presents large untapped renewable energy potential could significantly contribute to global energy needs. However, developing geothermal projects involves uncertainties regarding adequate geothe... Deep geothermal energy presents large untapped renewable energy potential could significantly contribute to global energy needs. However, developing geothermal projects involves uncertainties regarding adequate geothermal brine extraction and huge costs related to preparation phases and consequently drilling and stimulation activities. Therefore, evaluating utilization alternatives of such projects is a complex decision-making problem effectively addressed using multi-criteria decision-making (MCDM) methods. This study introduces the MCDM method utilizing analytic hierarchy process (AHP) and weighted decision matrix (WDM) to assess different utilization alternatives (electricity generation, direct heat use and cogeneration). The AHP method determines the weight of each criterion and sub-criterion, while the WDM calculates the final project grade. Five criteria groups - technological, geological, economic, societal and environmental – comprising twenty-eight influencing factors were selected and used for the assessment of investment in Enhanced Geothermal Systems (EGS) projects. The AHP-WDM method was used by 38 experts from six categories: industry, educational institution, research and technology organization (RTO), small- and medium-sized enterprises (SME), local community and other. These diverse expert inputs aimed to capture varying perspectives and knowledge influence investment decisions in geothermal energy. The results were analysed accordingly. The results underscore the importance of incorporating different viewpoints to develop robust, credible, and effective investment strategies for EGS projects. Therefore, this method will contribute to more efficient EGS project development, enabling thus a greater penetration of the EGS into the market. Additionally, the proposed AHP-WDM method was implemented for a case study examining two locations. Locations were assessed and compared on scenario-based evaluation. The results confirmed the method's adequacy for assessing various end uses and comparing project feasibility across different locations. 展开更多
关键词 Deep geothermal energy Enhanced geothermal systems(EGS) Multi-criteria decision-making(MCDM)method Analytic hierarchy process(AHP) weighted decision matrix(WDM)
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THE STABILITY OF A KIND OF DISCRETE-TIME HOPFIELD NEURAL NETWORKS WITH ASYMPTOTICAL WEIGHTED MATRICES
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作者 Guo Shujuan Ruan Jiong Tu Qingwei 《Annals of Differential Equations》 2006年第4期489-495,共7页
In this paper, the authors analyze the stability of a kind of discrete-time Hopfield neural network with asymptotical weighted matrix, which can be expressed as the product of a positive definite diagonal matrix and a... In this paper, the authors analyze the stability of a kind of discrete-time Hopfield neural network with asymptotical weighted matrix, which can be expressed as the product of a positive definite diagonal matrix and a symmetric matrix. We obtain that it has asymptotically stable equilibriums if the network is updated asynchronously, and asymptotically stable equilibriums or vibrating final stage with 2 period if updated synchronously. To prove these, Lassale's invariance principle in difference equation is applied. 展开更多
关键词 Hopfield neural network Lassale's invariance principle asymmetric weighted matrix equilibriums asymptotic stable vibration
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Spectral clustering based on matrix perturbation theory 被引量:19
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作者 TIAN Zheng LI XiaoBin JU YanWei 《Science in China(Series F)》 2007年第1期63-81,共19页
This paper exposes some intrlnsic chsracterlstlca of the spectral clustering method by using the tools from the mstrlx perturbation theory. We construct s welght mstrix of s graph and study Its elgenvalues and elgenve... This paper exposes some intrlnsic chsracterlstlca of the spectral clustering method by using the tools from the mstrlx perturbation theory. We construct s welght mstrix of s graph and study Its elgenvalues and elgenvectors. It shows that the number of clusters Is equal to the number of elgenvslues that are larger than 1, and the number of polnts In each of the clusters can be spproxlmsted by the associated elgenvslue. It also shows that the elgenvector of the weight rnatrlx can be used dlrectly to perform clusterlng; that Is, the dlrectlonsl angle between the two-row vectors of the mstrlx derlved from the elgenvectors Is s sultable distance measure for clustsrlng. As s result, an unsupervised spectral clusterlng slgorlthm based on welght mstrlx (USCAWM) Is developed. The experlmental results on s number of srtlficisl and real-world data sets show the correctness of the theoretical analysis. 展开更多
关键词 spectral clustering weight matrix spectrum of weight matrix number of the clusters unsupervised spectral clustering algorithm based on weight matrix
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Inverse Problems for the Dirac Operator on a Star Graph
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作者 Dai Quan LIU Chuan Fu YANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2023年第1期161-175,共15页
Following the previous work,we shall study some inverse problems for the Dirac operator on an equilateral star graph.It is proven that the so-called Weyl function uniquely determines the potentials.Furthermore,we pay ... Following the previous work,we shall study some inverse problems for the Dirac operator on an equilateral star graph.It is proven that the so-called Weyl function uniquely determines the potentials.Furthermore,we pay attention to the inverse problem of recovering the potentials from the spectral data,which consists of the eigenvalues and weight matrices,and present a constructive algorithm.The basic tool in this paper is the method of spectral mappings developed by Yurko. 展开更多
关键词 Inverse problem Dirac operator on graph Weyl function weight matrix
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A New Method for Calculating Priorities in AHP 被引量:4
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作者 XU Zeshui LU Jianjiang(Institute of Communications Engineering, Nanjing 210016, Jjangsu, China) 《Systems Science and Systems Engineering》 CSCD 1999年第2期179-188,共10页
On the basis of weight matrix, this paper presents a new optimizing approach to calculate priorities in the analytic hierarchy process(AHP), this method is a development of the synthetichierarchy method, which was pro... On the basis of weight matrix, this paper presents a new optimizing approach to calculate priorities in the analytic hierarchy process(AHP), this method is a development of the synthetichierarchy method, which was proposed by Lipovetsky in [2], it enables the united consideration of allhorizontal and vertical connections of a hierarchical system in a single optimizing objective functionbased on statistical models of the synthesis process. The ultimate priority vector is proportional tothe solution of a linear system or an eigenproblem of a matrix. A numerical example is also given.Theoretical analyses and the numerical example all show that the method is more practical and needsless time for obtaining priorities than that of IZ]. 展开更多
关键词 AHP SHM weight matrix
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Parameter Optimization of Linear Quadratic Controller Based on Genetic Algorithm 被引量:2
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作者 李纪敏 尚朝轩 邹明虎 《Tsinghua Science and Technology》 SCIE EI CAS 2007年第S1期208-211,共4页
The selection of weighting matrix in design of the linear quadratic optimal controller is an important topic in the control theory. In this paper, an approach based on genetic algorithm is presented for selecting the ... The selection of weighting matrix in design of the linear quadratic optimal controller is an important topic in the control theory. In this paper, an approach based on genetic algorithm is presented for selecting the weighting matrix for the optimal controller. Genetic algorithm is adaptive heuristic search algorithm premised on the evolutionary ideas of natural selection and genetic. In this algorithm, the fitness function is used to evaluate individuals and reproductive success varies with fitness. In the design of the linear quadratic optimal controller, the fitness function has relation to the anticipated step response of the system. Not only can the controller designed by this approach meet the demand of the performance indexes of linear quadratic controller, but also satisfy the anticipated step response of close-loop system. The method possesses a higher calculating efficiency and provides technical support for the optimal controller in engineering application. The simulation of a three-order single-input single-output (SISO) system has demonstrated the feasibility and validity of the approach. 展开更多
关键词 genetic algorithm weighting matrix linear quadratic controller parameter optimization
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