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线索贯穿 形聚神凝
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作者 蓝(图) 《小雪花(初中高分作文)》 2010年第1期37-39,共3页
牵挂是一种思念,牵挂是一种情谊,牵挂也是一种幸福。父母时儿女的牵挂是一份深深的爱:朋友对我们的牵挂是一份浓浓的关心;你的心中也许也会积存一份牵挂,梦萦魂牵。心中有牵挂,是一种拥有;爱人所牵挂,是一种收获。你对牵挂又有... 牵挂是一种思念,牵挂是一种情谊,牵挂也是一种幸福。父母时儿女的牵挂是一份深深的爱:朋友对我们的牵挂是一份浓浓的关心;你的心中也许也会积存一份牵挂,梦萦魂牵。心中有牵挂,是一种拥有;爱人所牵挂,是一种收获。你对牵挂又有怎样的体会? 展开更多
关键词 小学 课外阅读 阅读材料 《线索贯穿 形聚神凝》
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The group search-based parallel algorithm for the serial Monte Carlo inversion method 被引量:3
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作者 魏超 李小凡 郑晓东 《Applied Geophysics》 SCIE CSCD 2010年第2期127-134,193,共9页
With the development of parallel computing technology,non-linear inversion calculation efficiency has been improving.However,for single-point search-based non-linear inversion methods,the implementation of parallel al... With the development of parallel computing technology,non-linear inversion calculation efficiency has been improving.However,for single-point search-based non-linear inversion methods,the implementation of parallel algorithms is a difficult issue.We introduce the idea of group search to the single-point search-based non-linear inversion algorithm, taking the quantum Monte Carlo method as an example for two-dimensional seismic wave velocity inversion and practical impedance inversion and test the calculation efficiency of using different node numbers.The results show the parallel algorithm in theoretical and practical data inversion is feasible and effective.The parallel algorithm has good versatility. The algorithm efficiency increases with increasing node numbers but the algorithm efficiency rate of increase gradually decreases as the node numbers increase. 展开更多
关键词 non-linear inversion single-point search group search parallel computation
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NEW LIMITED MEMORY SYMMETRIC RANK ONE ALGORITHM FOR LARGE-SCALE UNCONSTRAINED OPTIMIZATION
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作者 刘浩 倪勤 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第3期235-239,共5页
A new limited memory symmetric rank one algorithm is proposed. It combines a modified self-scaled symmetric rank one (SSR1) update with the limited memory and nonmonotone line search technique. In this algorithm, th... A new limited memory symmetric rank one algorithm is proposed. It combines a modified self-scaled symmetric rank one (SSR1) update with the limited memory and nonmonotone line search technique. In this algorithm, the descent search direction is generated by inverse limited memory SSR1 update, thus simplifying the computation. Numerical comparison of the algorithm and the famous limited memory BFGS algorithm is given. Comparison results indicate that the new algorithm can process a kind of large-scale unconstrained optimization problems. 展开更多
关键词 optimization large scale systems symmetric rank one update nonmonotone line search limitedmemory algorithm
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Mechanical analysis of transmission lines based on linear sliding cable element
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作者 刘云 钱振东 夏开全 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期436-440,共5页
In order to study the sliding characteristics when the cable structures are connected with other rods, a string of sliding cable dements (SCE) consisting of one active threenode SCE passing through the sliding point... In order to study the sliding characteristics when the cable structures are connected with other rods, a string of sliding cable dements (SCE) consisting of one active threenode SCE passing through the sliding point and multiple inactive two-node SCEs is put forward. Based on the updated Lagrangian formulation, the geometric nonlinear stiffness matrix of the three-node straight sliding cable dement is deduced. The examples about two-span and three-span continuous cable structures are studied to verify the effectiveness of the derived SCE. Comparing the cable tension of SCE with the existing research results, the calculating results show that the error is less than 1%. The sliding characteristics should be considered in practical engineering because of the obvious difference between the cable tension of the SCE and that of the cable element without considering sliding characteristics. 展开更多
关键词 transmission line sliding cable element updated Lagrangian formulation geometric nonlinear
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Analysis and Design of Broadband Stacked Microstrip Patch Antennas 被引量:1
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作者 徐晓文 徐健 +2 位作者 刘章发 朱伯承 李世智 《Journal of Beijing Institute of Technology》 EI CAS 1997年第4期61-66,共6页
A broadband microstrip patch antenna was analyzed and designed.Full wave analysis method(FWAM) was employed to show that a stacked microstrip dual patch antenna(SMDPA) might have a much wider bandwidth than that of ... A broadband microstrip patch antenna was analyzed and designed.Full wave analysis method(FWAM) was employed to show that a stacked microstrip dual patch antenna(SMDPA) might have a much wider bandwidth than that of the ordinanry uni patch one.By means of discrete complex image theory(DCIT),the Sommerfeld integrals (SI) involved were accurately calculated at a speed several hundred times faster than numerical integration method(NIM).The feeding structure of the SMDPA was then improved and the bandwidth was extended to about 22% or more for voltage standing wave ratio (VSWR)s≤2 Finally,a matching network was constructed to obtain a bandwidth of about 25% for s≤1.5. 展开更多
关键词 broadband patch antennas full wave analysis complex image theory Sommerfeld integrals broadband matching
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A Modified Algorithm for Nonliear Integer Programming 被引量:2
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作者 孙会霞 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期24-29,共6页
Based on the analysis to the random sear ch algorithm of LUUS, a modified random directed integer search algorithm (MRDI SA) is given for first time. And a practical example is given to show that the adva ntage of th... Based on the analysis to the random sear ch algorithm of LUUS, a modified random directed integer search algorithm (MRDI SA) is given for first time. And a practical example is given to show that the adva ntage of this kind of algorithm is the reliability can’t be infuenced by the ini tial value X (0) and the start search domain R (0) . Besides, i t can be applied to solve the higher dimensional constrained nonlinear integer p rogramming problem. 展开更多
关键词 random search integer programming optimal soluti on RELIABILITY
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Aggregating metasearch engine results based on maximal entropy OWA operator
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作者 桑秀芝 刘新旺 《Journal of Southeast University(English Edition)》 EI CAS 2013年第2期139-144,共6页
The maximal entropy ordered weighted averaging (ME-OWA) operator is used to aggregate metasearch engine results, and its newly analytical solution is also applied. Within the current context of the OWA operator, the... The maximal entropy ordered weighted averaging (ME-OWA) operator is used to aggregate metasearch engine results, and its newly analytical solution is also applied. Within the current context of the OWA operator, the methods for aggregating metasearch engine results are divided into two kinds. One has a unique solution, and the other has multiple solutions. The proposed method not only has crisp weights, but also provides multiple aggregation results for decision makers to choose from. In order to prove the application of the ME-OWA operator method, under the context of aggregating metasearch engine results, an example is given, which shows the results obtained by the ME-OWA operator method and the minimax linear programming ( minimax-LP ) method. Comparison between these two methods are also made. The results show that the ME-OWA operator has nearly the same aggregation results as those of the minimax-LP method. 展开更多
关键词 maximal entropy ordered weighted averagingoperator minimax linear programming metasearch engine information aggregation
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Autonomous determination of orbit for probe around asteroids using unscented Kalman filter 被引量:1
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作者 崔平远 崔祜涛 +1 位作者 黄翔宇 栾恩杰 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第3期229-234,共6页
The observed images of the asteroid and the asteroid reference images are used to obtain the probe-to-asteroid direction and the location of the limb features of the asteroid in the inertial coordinate. These informa-... The observed images of the asteroid and the asteroid reference images are used to obtain the probe-to-asteroid direction and the location of the limb features of the asteroid in the inertial coordinate. These informa-tion in combination with the shape model of the asteroid and attitude information of the probe are utilized to ob-tain the position of the probe. The position information is then input to the UKF which determines the real-timeorbit of the probe. Finally, the autonomous orbit determination algorithm is validated using digital simulation.The determination of orbit using UKF is compared with that using extended Kalman filter (EKF), and the resultshows that UKF is superior to EKF. 展开更多
关键词 unscented Kalman filter extended Kalman filter autonomous determination of orbit probe around asteroids
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Smoothing Newton-Like Method for the Solution of Nonlinear Systems of Equalities and Inequalities 被引量:2
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作者 Liu Yang Yanping Chen Xiaojiao Tong 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2009年第2期224-236,共13页
In this paper,we present a smoothing Newton-like method for solving nonlinear systems of equalities and inequalities.By using the so-called max function,we transfer the inequalities into a system of semismooth equalit... In this paper,we present a smoothing Newton-like method for solving nonlinear systems of equalities and inequalities.By using the so-called max function,we transfer the inequalities into a system of semismooth equalities.Then a smoothing Newton-like method is proposed for solving the reformulated system,which only needs to solve one system of linear equations and to perform one line search at each iteration. The global and local quadratic convergence are studied under appropriate assumptions. Numerical examples show that the new approach is effective. 展开更多
关键词 Nonlinear systems of equalities and inequalities semismooth function smoothingNewton method global convergence local quadratic convergence.
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Avian orientation: multi-cue integration and calibration of compass systems
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作者 刘小峰 尼基塔.切尼佐夫 《Chinese Birds》 2012年第1期1-8,共8页
Migratory birds are known to use a number of different orientation cues to determine and maintain the direction of their movements. They are able to use at least three different sources of compass information, includi... Migratory birds are known to use a number of different orientation cues to determine and maintain the direction of their movements. They are able to use at least three different sources of compass information, including solar, stellar and geomagnetic cues. However, little is known about how these cues are calibrated into uniform reference direction information, while the hierarchy of these cues remains controversial. In recent studies, researchers suggest that avian migrants calibrate their geomagnetic compass on sunset cues, whereas others fail to find such patterns and insist on the prevalence of the magnetic compass. We carefully reviewed the existing literature and suggest that the conflicting results reported by different authors are due to genuine variation among species and propose hypotheses to explain this variation. 展开更多
关键词 BIRDS ORIENTATION compass system geomagnetic field solar cues
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Theoretical Study of Double Cost Function Linear Quadratic Regulator(LQR)
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作者 姜澜 王信义 永井正夫 《Journal of Beijing Institute of Technology》 EI CAS 2000年第1期80-86,共7页
Double cost function linear quadratic regulator (DLQR) is developed from LQR theory to solve an optimal control problem with a general nonlinear cost function. In addition to the traditional LQ cost function, anothe... Double cost function linear quadratic regulator (DLQR) is developed from LQR theory to solve an optimal control problem with a general nonlinear cost function. In addition to the traditional LQ cost function, another free form cost function was introduced to express the physical need plainly and optimize weights of LQ cost function using the search algorithms. As an instance, DLQR was applied in determining the control input in the front steering angle compensation control (FSAC) model for heavy duty vehicles. The brief simulations show that DLQR is powerful enough to specify the engineering requirements correctly and balance many factors effectively. The concept and applicable field of LQR are expanded by DLQR to optimize the system with a free form cost function. 展开更多
关键词 optimal control linear quadratic regulator (LQR) search algorithm front steering angle compensation control
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Mechanical response of transmission lines based on sliding cable element 被引量:4
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作者 刘云 钱振东 夏开全 《Journal of Central South University》 SCIE EI CAS 2014年第8期3370-3377,共8页
In order to study the sliding characteristics when the cable is connected with the other rods in the transmission line structures,a linear sliding cable element based on updated Lagrangian formulation and a sliding ca... In order to study the sliding characteristics when the cable is connected with the other rods in the transmission line structures,a linear sliding cable element based on updated Lagrangian formulation and a sliding catenary element considering the out-of-plane stiffness coefficient are put forward.A two-span and a three-span cable structures are taken as examples to verify the sliding cable elements.By comparing the tensions of the two proposed cable elements with the existing research results,the error is less than 1%,which proves the correctness of the proposed elements.The sliding characteristics should be considered in the practical engineering because of the significant difference between the tensions of sliding cable elements and those of cable element without considering sliding.The out-of-plane stiffness coefficient and friction characteristics do not obviously affect the cable tensions. 展开更多
关键词 transmission lines sliding cable element updated Lagrangian formulation geometric nonlinearity mechanical response
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Linear manifold clustering for high dimensional data based on line manifold searching and fusing 被引量:1
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作者 黎刚果 王正志 +2 位作者 王晓敏 倪青山 强波 《Journal of Central South University》 SCIE EI CAS 2010年第5期1058-1069,共12页
High dimensional data clustering,with the inherent sparsity of data and the existence of noise,is a serious challenge for clustering algorithms.A new linear manifold clustering method was proposed to address this prob... High dimensional data clustering,with the inherent sparsity of data and the existence of noise,is a serious challenge for clustering algorithms.A new linear manifold clustering method was proposed to address this problem.The basic idea was to search the line manifold clusters hidden in datasets,and then fuse some of the line manifold clusters to construct higher dimensional manifold clusters.The orthogonal distance and the tangent distance were considered together as the linear manifold distance metrics. Spatial neighbor information was fully utilized to construct the original line manifold and optimize line manifolds during the line manifold cluster searching procedure.The results obtained from experiments over real and synthetic data sets demonstrate the superiority of the proposed method over some competing clustering methods in terms of accuracy and computation time.The proposed method is able to obtain high clustering accuracy for various data sets with different sizes,manifold dimensions and noise ratios,which confirms the anti-noise capability and high clustering accuracy of the proposed method for high dimensional data. 展开更多
关键词 linear manifold subspace clustering line manifold data mining data fusing clustering algorithm
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A New Nonlinear Conjugate Gradient Method for Unconstrained Optimization Problems 被引量:1
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作者 LIU Jin-kui WANG Kai-rong +1 位作者 SONG Xiao-qian DU Xiang-lin 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第3期444-450,共7页
In this paper,an efficient conjugate gradient method is given to solve the general unconstrained optimization problems,which can guarantee the sufficient descent property and the global convergence with the strong Wol... In this paper,an efficient conjugate gradient method is given to solve the general unconstrained optimization problems,which can guarantee the sufficient descent property and the global convergence with the strong Wolfe line search conditions.Numerical results show that the new method is efficient and stationary by comparing with PRP+ method,so it can be widely used in scientific computation. 展开更多
关键词 unconstrained optimization conjugate gradient method strong Wolfe line search sufficient descent property global convergence
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A Tabu Search Algorithm for Quadratic 0-1 Programming Problem 被引量:2
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作者 周贤伟 王远允 +1 位作者 田新现 郭瑞强 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第4期98-102, ,共5页
In this paper,quadratic 0-1 programming problem (I) is considered, in terms of its features quadratic 0-1 programming problem is solved by linear approxity heurstic algrothm and a developed tabu search ahgrothm .
关键词 Tabu search linear approximate quaratic 0-1 programming
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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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Regularization Semismooth Newton Method for P_0-NCPs with Non-monotone Line Search
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作者 王萍 臧玉卫 张颖 《Transactions of Tianjin University》 EI CAS 2010年第2期138-141,共4页
Based on the generalized Fischer-Burmeister function, Chen et al in 2008 put forward a regularization semismooth Newton method for solving the nonlinear complementarity problem with a P0-function. In this paper, we in... Based on the generalized Fischer-Burmeister function, Chen et al in 2008 put forward a regularization semismooth Newton method for solving the nonlinear complementarity problem with a P0-function. In this paper, we investigate the above algorithm with the monotone line search replaced by a non-monotone line search. It is shown that the non-monotone algorithm is well-defined, and is globally and locally superlinearly convergent under standard assumptions. 展开更多
关键词 NONLINEARITY complementarity semismooth Newton method Fischer-Burrneister function
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Estimation of mass transfer coefficient in ozone absorption by linear least square fitting and Simplex search methods 被引量:1
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作者 海景 张刚 程江 《Journal of Central South University》 SCIE EI CAS 2012年第12期3396-3399,共4页
For physical ozone absorption without reaction,two parametric estimation methods,i.e.the common linear least square fitting and non-linear Simplex search methods,were applied,respectively,to determine the ozone mass t... For physical ozone absorption without reaction,two parametric estimation methods,i.e.the common linear least square fitting and non-linear Simplex search methods,were applied,respectively,to determine the ozone mass transfer coefficient during absorption and both methods give almost the same mass transfer coefficient.While for chemical absorption with ozone decomposition reaction,the common linear least square fitting method is not applicable for the evaluation of ozone mass transfer coefficient due to the difficulty of model linearization for describing ozone concentration dissolved in water.The nonlinear Simplex method obtains the mass transfer coefficient by minimizing the sum of the differences between the simulated and experimental ozone concentration during the whole absorption process,without the limitation of linear relationship between the dissolved ozone concentration and absorption time during the initial stage of absorption.Comparison of the ozone concentration profiles between the simulation and experimental data demonstrates that Simplex method may determine ozone mass transfer coefficient during absorption in an accurate and high efficiency way with wide applicability. 展开更多
关键词 linear least square fitting Simplex search method ozone absorption mass transfer coefficient
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A RECURSIVE QUADRATIC PROGRAMMING ALGORITHM THAT USES A NEW NONDIFFERENTIABLE PENALTY FUNCTIONS
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作者 YANGBOTING ZHANGKECUN 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1994年第1期95-103,共9页
In this papert a recursive quadratic programming algorithm is proposed andstudied.The line search functions used are Han's nondifferentiable penalty functionswith a second order penalty term. In order to avoid mar... In this papert a recursive quadratic programming algorithm is proposed andstudied.The line search functions used are Han's nondifferentiable penalty functionswith a second order penalty term. In order to avoid maratos effect,Fukushima's mixeddirection is used as the direction of line search.Finallyt we prove the global convergenceand the local second order convergence of the algorithm. 展开更多
关键词 Nonlinear Programming Line Search Penalty Function Maratos Efficient Convergence.
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Global Convergence of a New Restarting Conjugate Gradient Method for Nonlinear Optimizations 被引量:1
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作者 SUN Qing-ying(Department of Applied Mathematics, Dalian University of Technology, Dalian 116024, China Department of Applied Mathematics, University of Petroleum , Dongying 257061, China) 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第2期154-162,共9页
Conjugate gradient optimization algorithms depend on the search directions with different choices for the parameters in the search directions. In this note, by combining the nice numerical performance of PR and HS met... Conjugate gradient optimization algorithms depend on the search directions with different choices for the parameters in the search directions. In this note, by combining the nice numerical performance of PR and HS methods with the global convergence property of the class of conjugate gradient methods presented by HU and STOREY(1991), a class of new restarting conjugate gradient methods is presented. Global convergences of the new method with two kinds of common line searches, are proved. Firstly, it is shown that, using reverse modulus of continuity function and forcing function, the new method for solving unconstrained optimization can work for a continously dif ferentiable function with Curry-Altman's step size rule and a bounded level set. Secondly, by using comparing technique, some general convergence properties of the new method with other kind of step size rule are established. Numerical experiments show that the new method is efficient by comparing with FR conjugate gradient method. 展开更多
关键词 nonlinear programming restarting conjugate gradient method forcing function reverse modulus of continuity function CONVERGENCE
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