Applied Numerical Analysis & Computational Mathematics最新文献_第4页

Extended One-Step Methods: An Exponential Fitting Approach 扩展一步法:指数拟合方法

Applied Numerical Analysis & Computational Mathematics Pub Date : 2004-12-22 DOI: 10.1002/anac.200410003

M. Van Daele, G. Vanden Berghe

引用次数: 10

Phase Space Stability Error Control with Variable Time-stepping Runge-Kutta Methods for Dynamical Systems 动态系统的变时步龙格-库塔法相空间稳定性误差控制

Applied Numerical Analysis & Computational Mathematics Pub Date : 2004-12-22 DOI: 10.1002/anac.200410010

Tony Humphries, R. Vigneswaran

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引用次数: 1

Efficient Implementation of the Nelder–Mead Search Algorithm Nelder-Mead搜索算法的高效实现

Applied Numerical Analysis & Computational Mathematics Pub Date : 2004-12-22 DOI: 10.1002/anac.200410015

Saša Singer, Sanja Singer

{"title":"Efficient Implementation of the Nelder–Mead Search Algorithm","authors":"Saša Singer, Sanja Singer","doi":"10.1002/anac.200410015","DOIUrl":"10.1002/anac.200410015","url":null,"abstract":"The Nelder–Mead or simplex search algorithm is one of the best known algorithms for unconstrained optimization of non–smooth functions. Even though the basic algorithm is quite simple, it is implemented in many different ways. Apart from some minor computational details, the main difference between various implementations lies in the selection of convergence (or termination) tests, which are used to break the iteration process. A fairly simple efficiency analysis of each iteration step reveals a potential computational bottleneck in the domain convergence test. To be efficient, such a test has to be sublinear in the number of vertices of the working simplex. We have tested some of the most common implementations of the Nelder–Mead algorithm, and none of them is efficient in this sense.Therefore, we propose a simple and efficient domain convergence test and discuss some of its properties. This test is based on tracking the volume of the working simplex throughout the iterations. Similar termination tests can also be applied in some other simplex–based direct search methods. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)","PeriodicalId":100108,"journal":{"name":"Applied Numerical Analysis & Computational Mathematics","volume":"1 2","pages":"524-534"},"PeriodicalIF":0.0,"publicationDate":"2004-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/anac.200410015","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88683739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 57

Optimal Control of Geodesics in Riemannian Manifolds 黎曼流形测地线的最优控制

Applied Numerical Analysis & Computational Mathematics Pub Date : 2004-12-22 DOI: 10.1002/anac.200410013

Roland Rozsnyo, Klaus-Dieter Semmler

引用次数: 2

On Stability of Weak Schemes for Stochastic Differential Systems With One Multiplicative Noise 具有一个乘性噪声的随机微分系统弱格式的稳定性

Applied Numerical Analysis & Computational Mathematics Pub Date : 2004-12-22 DOI: 10.1002/anac.200410005

Marwan I. Abukhaled

引用次数: 1

Preconditioning the Mortar Method by Substructuring: The High Order Case. 用子结构预处理砂浆法:高阶情况。

Applied Numerical Analysis & Computational Mathematics Pub Date : 2004-12-22 DOI: 10.1002/anac.200410008

S. Bertoluzza, M. Pennacchio

引用次数: 9

Partitioned Linear Multistep Method for Long Term Integration of the N-Body Problem n体问题长期积分的分段线性多步法

Applied Numerical Analysis & Computational Mathematics Pub Date : 2004-12-22 DOI: 10.1002/anac.200410017

D. S. Vlachos, T. E. Simos

引用次数: 47

Region and Contour Identification of Physical Objects 物理对象的区域和轮廓识别

Applied Numerical Analysis & Computational Mathematics Pub Date : 2004-12-22 DOI: 10.1002/anac.200410002

Annie Cuyt, Jan Sijbers, Brigitte Verdonk, Dirk Van Dyck

{"title":"Region and Contour Identification of Physical Objects","authors":"Annie Cuyt, Jan Sijbers, Brigitte Verdonk, Dirk Van Dyck","doi":"10.1002/anac.200410002","DOIUrl":"10.1002/anac.200410002","url":null,"abstract":"The region occupied by and the contour of a physical object in 3-dimensional space are in a way dual or interchangeable characteristics of the object: the contour is the region's boundary and the region is contained inside the contour. In the same way the characterization of the object's contour by its Fourier descriptors, and the reconstruction of its region from the object's multidimensional moments, are also dual problems. While both problems are well-understood in two dimensions, the complexity increases tremendously when moving to the three-dimensional world.In Section 2 we discuss how the latest techniques allow to reconstruct an object's shape from the knowledge of its moments. For 2D significantly different techniques must be used, compared to the general 3D case. In Section 3, the parameterization of a 2D contour onto a unit circle and a 3D surface onto a unit sphere is described. Furthermore, the theory of Fourier descriptors for 2D shape representation and the extension to 3D shape analysis are discussed.The reader familiar with the use of either Fourier descriptors or moments as shape descriptors of physical objects may find the comparative discussion in the concluding section interesting. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)","PeriodicalId":100108,"journal":{"name":"Applied Numerical Analysis & Computational Mathematics","volume":"1 2","pages":"343-352"},"PeriodicalIF":0.0,"publicationDate":"2004-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/anac.200410002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86119735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Design and Analysis of Optimization Algorithms Using Computational Statistics 基于计算统计学的优化算法设计与分析

Applied Numerical Analysis & Computational Mathematics Pub Date : 2004-12-22 DOI: 10.1002/anac.200410007

T. Bartz–Beielstein, K. E. Parsopoulos, M. N. Vrahatis

引用次数: 85

The Use of the l1 and l∞ Norms in Fitting Parametric Curves and Surfaces to Data l1和l∞范数在拟合参数曲线和曲面上的应用

Applied Numerical Analysis & Computational Mathematics Pub Date : 2004-12-22 DOI: 10.1002/anac.200410004

I. Al-Subaihi, G. A. Watson

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引用次数: 15