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Numerical simulation of the welding deformation for the side sill of the bogie frame based on local-global method 被引量:13
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作者 杨鑫华 王春生 +2 位作者 常力 李娅娜 兆文忠 《China Welding》 EI CAS 2007年第4期11-16,共6页
Considering the limitation of computational capacity, a new finite element solution is used to simulate the welding deformation of the side sill of railroad car' s bogie frame based on the local-global method. Firstl... Considering the limitation of computational capacity, a new finite element solution is used to simulate the welding deformation of the side sill of railroad car' s bogie frame based on the local-global method. Firstly, a volumetric heat source defined by a double ellipsoid is adopted to simulate the thermal distributions of the arc welding process. And then, the local models extracted from the global model are computed with refined meshes. On these bases, the global distortions of the subject studied are ascertained by transferring the inner forces of computed local models to the global model. It indicates that the local-global method is feasible for simulating the large welded structures by comparing the computed results with the corresponding actual measured values. The work provides basis for optimizing the welding sequence and clamping conditions, and has theoretical values and engineering significance in the integral design, manufacturing technique selection of the bogie frame, as well as other kinds of large welded structures. 展开更多
关键词 welding deformation numerical simulation local-global method
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A New Class of Nonlinear Conjugate Gradient Methods with Global Convergence Properties 被引量:1
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作者 陈忠 《长江大学学报(自科版)(上旬)》 CAS 2014年第3期I0001-I0003,共3页
非线性共轭梯度法由于其迭代简单和储存量小,且搜索方向不需要满足正割条件,在求解大规模无约束优化问题时占据及其重要的地位.提出了一类新的共轭梯度法,其搜索方向是目标函数的下降方向.若假设目标函数连续可微且梯度满足Lipschitz条... 非线性共轭梯度法由于其迭代简单和储存量小,且搜索方向不需要满足正割条件,在求解大规模无约束优化问题时占据及其重要的地位.提出了一类新的共轭梯度法,其搜索方向是目标函数的下降方向.若假设目标函数连续可微且梯度满足Lipschitz条件,线性搜索满足Wolfe原则,讨论了所设计算法的全局收敛性. 展开更多
关键词 摘要 编辑部 编辑工作 读者
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Global quasi-minimal residual method for the Sylvester equations 被引量:1
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作者 汪勇 顾桂定 《Journal of Shanghai University(English Edition)》 CAS 2007年第1期52-57,共6页
In this paper, a global quasi-minimal residual (QMR) method was presented for solving the Sylvester equations. Some properties were investigated with a new matrix product for the global QMR method. Numerical results... In this paper, a global quasi-minimal residual (QMR) method was presented for solving the Sylvester equations. Some properties were investigated with a new matrix product for the global QMR method. Numerical results with the global QMR and GMRES methods compared with the block GMRES method were given. The results show that the global QMR method is less time-consuming than the global GMRES (generalized minimal residual) and block GMRES methods in some cases. 展开更多
关键词 global Krylov subspace Sylvester equations global QMR method
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Smart Society and Artificial Intelligence:Big Data Scheduling and the Global Standard Method Applied to Smart Maintenance 被引量:1
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作者 Ruben Foresti Stefano Rossi +2 位作者 Matteo Magnani Corrado Guarino Lo Bianco Nicola Delmonte 《Engineering》 SCIE EI 2020年第7期835-846,共12页
The implementation of artificial intelligence(AI)in a smart society,in which the analysis of human habits is mandatory,requires automated data scheduling and analysis using smart applications,a smart infrastructure,sm... The implementation of artificial intelligence(AI)in a smart society,in which the analysis of human habits is mandatory,requires automated data scheduling and analysis using smart applications,a smart infrastructure,smart systems,and a smart network.In this context,which is characterized by a large gap between training and operative processes,a dedicated method is required to manage and extract the massive amount of data and the related information mining.The method presented in this work aims to reduce this gap with near-zero-failure advanced diagnostics(AD)for smart management,which is exploitable in any context of Society 5.0,thus reducing the risk factors at all management levels and ensuring quality and sustainability.We have also developed innovative applications for a humancentered management system to support scheduling in the maintenance of operative processes,for reducing training costs,for improving production yield,and for creating a human–machine cyberspace for smart infrastructure design.The results obtained in 12 international companies demonstrate a possible global standardization of operative processes,leading to the design of a near-zero-failure intelligent system that is able to learn and upgrade itself.Our new method provides guidance for selecting the new generation of intelligent manufacturing and smart systems in order to optimize human–machine interactions,with the related smart maintenance and education. 展开更多
关键词 Smart maintenance Smart society Artificial intelligence Human-centered management system Big data scheduling global standard method Society 5.0 Industry 4.0
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A GLOBAL LINEAR AND LOCAL QUADRATIC SINGLE-STEP NONINTERIOR CONTINUATION METHOD FOR MONOTONE SEMIDEFINITE COMPLEMENTARITY PROBLEMS 被引量:1
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作者 张立平 《Acta Mathematica Scientia》 SCIE CSCD 2007年第2期243-253,共11页
A noninterior continuation method is proposed for semidefinite complementarity problem (SDCP). This method improves the noninterior continuation methods recently developed for SDCP by Chen and Tseng. The main proper... A noninterior continuation method is proposed for semidefinite complementarity problem (SDCP). This method improves the noninterior continuation methods recently developed for SDCP by Chen and Tseng. The main properties of our method are: (i) it is well d.efined for the monotones SDCP; (ii) it has to solve just one linear system of equations at each step; (iii) it is shown to be both globally linearly convergent and locally quadratically convergent under suitable assumptions. 展开更多
关键词 Semidefinite complementarity problem noninterior continuation method global convergence local quadratic convergence
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A Globally Convergent Polak-Ribiere-Polyak Conjugate Gradient Method with Armijo-Type Line Search 被引量:11
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作者 Gaohang Yu Lutai Guan Zengxin Wei 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2006年第4期357-366,共10页
In this paper, we propose a globally convergent Polak-Ribiere-Polyak (PRP) conjugate gradient method for nonconvex minimization of differentiable functions by employing an Armijo-type line search which is simpler and ... In this paper, we propose a globally convergent Polak-Ribiere-Polyak (PRP) conjugate gradient method for nonconvex minimization of differentiable functions by employing an Armijo-type line search which is simpler and less demanding than those defined in [4,10]. A favorite property of this method is that we can choose the initial stepsize as the one-dimensional minimizer of a quadratic modelΦ(t):= f(xk)+tgkTdk+(1/2) t2dkTQkdk, where Qk is a positive definite matrix that carries some second order information of the objective function f. So, this line search may make the stepsize tk more easily accepted. Preliminary numerical results show that this method is efficient. 展开更多
关键词 非约束最优化 共轭梯度法 整体收敛 可微函数
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Reliability Optimization of Entropy Based Series-Parallel System Using Global Criterion Method
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作者 G. S. MAHAPATRA 《Intelligent Information Management》 2009年第3期145-149,共5页
In this paper, we have considered a series-parallel system to find out optimum system reliability with an additional entropy objective function. Maximum system reliability of series-parallel system is depending on pro... In this paper, we have considered a series-parallel system to find out optimum system reliability with an additional entropy objective function. Maximum system reliability of series-parallel system is depending on proper allocation of redundancy component in different stage. The goal of entropy based reliability redundancy allocation problem is to find optimal number of redundancy component in each stage such a manner that maximize the system reliability subject to available total system cost. Global criterion method is used to analyze entropy based reliability optimization problem with different weight function of objective functions. Numerical examples have been provided to illustrate the model. 展开更多
关键词 RELIABILITY SERIES-PARALLEL system REDUNDANCY ENTROPY global CRITERION method
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Reconstructions for Continuous-Wave Diffuse Optical Tomography by a Globally Convergent Method
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作者 Jianzhong Su Yueming Liu +4 位作者 Zi-Jing Lin Steven Teng Aubrey Rhoden Natee Pantong Hanli Liu 《Journal of Applied Mathematics and Physics》 2014年第5期204-213,共10页
In this paper, a novel reconstruction method is presented for Near Infrared (NIR) 2-D imaging to recover optical absorption coefficients from laboratory phantom data. The main body of this work validates a new generat... In this paper, a novel reconstruction method is presented for Near Infrared (NIR) 2-D imaging to recover optical absorption coefficients from laboratory phantom data. The main body of this work validates a new generation of highly efficient reconstruction algorithms called “Globally Convergent Method” (GCM) based upon actual measurements taken from brain-shape phantoms. It has been demonstrated in earlier studies using computer-simulated data that this type of reconstructions is stable for imaging complex distributions of optical absorption. The results in this paper demonstrate the excellent capability of GCM in working with experimental data measured from optical phantoms mimicking a rat brain with stroke. 展开更多
关键词 INVERSE Problems DIFFUSE Optical TOMOGRAPHY Medical and Biological Imaging globally Convergence method
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A GLOBALLY AND SUPERLINEARLY CONVERGENT TRUST REGION METHOD FOR LC^1 OPTIMIZATION PROBLEMS 被引量:1
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作者 Zhang Liping Lai Yanlian Institute of Applied Mathematics,Academia Sinica,Beijing 100080. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第1期72-80,共9页
A new trust region algorithm for solving convex LC 1 optimization problem is presented.It is proved that the algorithm is globally convergent and the rate of convergence is superlinear under some reasonable assum... A new trust region algorithm for solving convex LC 1 optimization problem is presented.It is proved that the algorithm is globally convergent and the rate of convergence is superlinear under some reasonable assumptions. 展开更多
关键词 LC 1 optimization problem global and superlinear convergence trust region method.
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GLOBAL COVERGENCE OF THE NON-QUASI-NEWTON METHOD FOR UNCONSTRAINED OPTIMIZATION PROBLEMS 被引量:6
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作者 Liu Hongwei Wang Mingjie +1 位作者 Li Jinshan Zhang Xiangsun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第3期276-288,共13页
In this paper, the non-quasi-Newton's family with inexact line search applied to unconstrained optimization problems is studied. A new update formula for non-quasi-Newton's family is proposed. It is proved that the ... In this paper, the non-quasi-Newton's family with inexact line search applied to unconstrained optimization problems is studied. A new update formula for non-quasi-Newton's family is proposed. It is proved that the constituted algorithm with either Wolfe-type or Armijotype line search converges globally and Q-superlinearly if the function to be minimized has Lipschitz continuous gradient. 展开更多
关键词 non-quasi-Newton method inexact line search global convergence unconstrained optimization superlinear convergence.
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A CLASS OF TRUST REGION METHODS FOR LINEAR INEQUALITY CONSTRAINED OPTIMIZATION AND ITS THEORY ANALYSIS:I.ALGORITHM AND GLOBAL CONVERGENCEXIU NAIHUA
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作者 XIU NAIHUA 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1995年第3期287-296,共10页
A class of trust region methods for solving linear inequality constrained problems is proposed in this paper. It is shown that the algorithm is of global convergence.The algorithm uses a version of the two-sided proje... A class of trust region methods for solving linear inequality constrained problems is proposed in this paper. It is shown that the algorithm is of global convergence.The algorithm uses a version of the two-sided projection and the strategy of the unconstrained trust region methods. It keeps the good convergence properties of the unconstrained case and has the merits of the projection method. In some sense, our algorithm can be regarded as an extension and improvement of the projected type algorithm. 展开更多
关键词 Linear inequality constrained optimization trust region method global convergence
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STRAIGHTFORWARD MULTI-SCALE BOUNDARY ELEMENT METHOD FOR GLOBAL/LOCAL MECHANICAL ANALYSIS OF ELASTIC HETEROGENEOUS MATERIAL
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作者 高希光 宋迎东 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2013年第2期145-154,共10页
A straightforward multi-scale boundary element method is proposed for global and local mechanical analysis of heterogeneous material.The method is more accurate and convenient than finite element based multi-scale met... A straightforward multi-scale boundary element method is proposed for global and local mechanical analysis of heterogeneous material.The method is more accurate and convenient than finite element based multi-scale method.The formulations of this method are derived by combining the homogenization approach and the fundamental equations of boundary element method.The solution gives the convenient formulations to compute global elastic constants and the local stress field.Finally,two numerical examples of porous material are presented to prove the accuracy and the efficiency of the proposed method.The results show that the method does not require the iteration to obtain the solution of the displacement in micro level. 展开更多
关键词 multi-scale method boundary element method MICROSTRUCTURE homogenization method global elastic properties
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GLOBAL LINEAR AND QUADRATIC ONE-STEP SMOOTHING NEWTON METHOD FOR VERTICAL LINEAR COMPLEMENTARITY PROBLEMS
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作者 张立平 高自友 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第6期738-746,F003,共10页
A one_step smoothing Newton method is proposed for solving the vertical linear complementarity problem based on the so_called aggregation function. The proposed algorithm has the following good features: (ⅰ) It solve... A one_step smoothing Newton method is proposed for solving the vertical linear complementarity problem based on the so_called aggregation function. The proposed algorithm has the following good features: (ⅰ) It solves only one linear system of equations and does only one line search at each iteration; (ⅱ) It is well_defined for the vertical linear complementarity problem with vertical block P 0 matrix and any accumulation point of iteration sequence is its solution.Moreover, the iteration sequence is bounded for the vertical linear complementarity problem with vertical block P 0+R 0 matrix; (ⅲ) It has both global linear and local quadratic convergence without strict complementarity. Many existing smoothing Newton methods do not have the property (ⅲ). 展开更多
关键词 vertical linear complementarity problems smoothing Newton method global linear convergence quadratic convergence
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Global Convergence of Curve Search Methods for Unconstrained Optimization
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作者 Zhiwei Xu Yongning Tang Zhen-Jun Shi 《Applied Mathematics》 2016年第7期721-735,共15页
In this paper we propose a new family of curve search methods for unconstrained optimization problems, which are based on searching a new iterate along a curve through the current iterate at each iteration, while line... In this paper we propose a new family of curve search methods for unconstrained optimization problems, which are based on searching a new iterate along a curve through the current iterate at each iteration, while line search methods are based on finding a new iterate on a line starting from the current iterate at each iteration. The global convergence and linear convergence rate of these curve search methods are investigated under some mild conditions. Numerical results show that some curve search methods are stable and effective in solving some large scale minimization problems. 展开更多
关键词 Unconstrained Optimization Curve Search method global Convergence Convergence Rate
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A FILTER-TRUST-REGION METHOD FOR LC^1 UNCONSTRAINED OPTIMIZATION AND ITS GLOBAL CONVERGENCE 被引量:1
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作者 ZhenghaoYang Wenyu Sun Chuangyin Dang 《Analysis in Theory and Applications》 2008年第1期55-66,共12页
In this paper we present a filter-trust-region algorithm for solving LC1 unconstrained optimization problems which uses the second Dini upper directional derivative. We establish the global convergence of the algorith... In this paper we present a filter-trust-region algorithm for solving LC1 unconstrained optimization problems which uses the second Dini upper directional derivative. We establish the global convergence of the algorithm under reasonable assumptions. 展开更多
关键词 nonsmooth optimization filter method trust region algorithm global conver- gence LC1 optimization
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GLOBAL CONVERGENCE OF THE GENERAL THREE TERM CONJUGATE GRADIENT METHODS WITH THE RELAXED STRONG WOLFE LINE SEARCH
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作者 Xu Zeshui Yue ZhenjunInstitute of Sciences,PLA University of Science and Technology,Nanjing,210016. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第1期58-62,共5页
The global convergence of the general three term conjugate gradient methods with the relaxed strong Wolfe line search is proved.
关键词 Conjugate gradient method inexact line search global convergence.
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An Enhanced Steepest Descent Method for Global Optimization-Based Mesh Smoothing 被引量:1
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作者 Kang Zhao Yabang Ma +2 位作者 You Wang Xin Yin Yufei Guo 《Journal of Applied Mathematics and Physics》 2020年第11期2509-2518,共10页
<div style="text-align:justify;"> In order to speed up the global optimization-based mesh smoothing, an enhanced steepest descent method is presented in the paper. Numerical experiment results show tha... <div style="text-align:justify;"> In order to speed up the global optimization-based mesh smoothing, an enhanced steepest descent method is presented in the paper. Numerical experiment results show that the method performs better than the steepest descent method in the global smoothing. We also presented a physically-based interpretation to explain why the method works better than the steepest descent method. </div> 展开更多
关键词 MESH Mesh Smoothing global Mesh Smoothing Optimization-Based Steepest Descent method
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ON THE GLOBAL CONVERGENCE OF CONJUGATE GRADIENT METHODS WITH INEXACT LINESEARCH
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作者 刘光辉 韩继业 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1995年第2期147-153,共7页
In this paper we consider the global convergence of any conjugate gradient method of the form d1=-g1,dk+1=-gk+1+βkdk(k≥1)with any βk satisfying sume conditions,and with the strong wolfe line search conditions.Under... In this paper we consider the global convergence of any conjugate gradient method of the form d1=-g1,dk+1=-gk+1+βkdk(k≥1)with any βk satisfying sume conditions,and with the strong wolfe line search conditions.Under the convex assumption on the objective function,we preve the descenf property and the global convergence of this method. 展开更多
关键词 CONJUGATE GRADIENT method STRONG Wolfe line SEARCH global convergence.
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Hybrid method for global optimization using more accuracy interval computation
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作者 崔中浩 雷咏梅 《Journal of Shanghai University(English Edition)》 CAS 2011年第5期445-450,共6页
In this paper, a novel hybrid method is presented for finding global optimization of an objective function. Based on the interval computation, this hybrid method combines interval deterministic method and stochastic e... In this paper, a novel hybrid method is presented for finding global optimization of an objective function. Based on the interval computation, this hybrid method combines interval deterministic method and stochastic evolution method. It can find global optimization quickly while ensuring the deterministic and stability of the algorithm. When using interval computation, extra width constraints accuracy of interval computation results. In this paper, a splitting method to reduce the extra width is introduced. This method is easy and it can get a more precise interval computation result. When finding the global optimization, it can increase the efficiency of pruning. Several experiments are given to illustrate the advantage of the new hybrid method. 展开更多
关键词 interval arithmetic global optimization interval computation extra width hybrid method
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A two scaled numerical method for global analysis of high dimensional nonlinear systems
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作者 Jun Jiang) MOE Key Laboratory of Strength and Vibration, Xi’an Jiaotong University, Xi’an 710079, China 《Theoretical & Applied Mechanics Letters》 CAS 2011年第6期45-50,共6页
This paper first analyzes the features of two classes of numerical methods for global analysis of nonlinear dynamical systems, which regard state space respectively as continuous and discrete ones. On basis of this un... This paper first analyzes the features of two classes of numerical methods for global analysis of nonlinear dynamical systems, which regard state space respectively as continuous and discrete ones. On basis of this understanding it then points out that the previously proposed method of point mapping under cell reference (PMUCR), has laid a frame work for the development of a two scaled numerical method suitable for the global analysis of high dimensional nonlinear systems, which may take the advantages of both classes of single scaled methods but will release the difficulties induced by the disadvantages of them. The basic ideas and main steps of implementation of the two scaled method, namely extended PMUCR, are elaborated. Finally, two examples are presented to demonstrate the capabilities of the proposed method. 展开更多
关键词 nonlinear systems global analysis multi-scaled numerical methods point mapping cell mapping point mapping under cell reference
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