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A Usable Selection Range Standard Based on Test Suite Reduction Algorithms
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作者 MA Yanjun ZHAO Zhigang +1 位作者 LIANG Yuchen YUN Maojin 《Wuhan University Journal of Natural Sciences》 CAS 2010年第3期261-266,共6页
In this paper, we analyze the features and distinctions of 6 classical algorithms: greedy algorithm (G), greedy evolution algorithm (GE), heuristics algorithm (H), greedy heuristic G (GRE), integer linear pro... In this paper, we analyze the features and distinctions of 6 classical algorithms: greedy algorithm (G), greedy evolution algorithm (GE), heuristics algorithm (H), greedy heuristic G (GRE), integer linear programming algorithm (ILP) and genetic algorithm (GA) to ensure the main influencing factors-the performance of algorithms and the running time of algorithms. What's more, we would not only present a research design that aims at gaining deeper understanding about the algorithm classification and its function as well as their distinction, but also make an empirical study in order to obtain a practical range standard that can guide the selection of reduction algorithms. When the size of a test object (product of test requirements and test cases) is smaller than 2000×2000, G algorithm is the commonly recommended algorithm. With the growth of test size, the usage of GE and GRE becomes more general. 展开更多
关键词 test suite reduction algorithms influencing factor selection standard
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ARNOLDI REDUCTION ALGORITHM FOR LARGE SCALE GYROSCOPIC EIGENVALUE PROBLEM
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作者 Zheng Zhaochang Ren Gexue, Department of Engineering Mechanics, Tsinghua University, Beijing 100084 《Acta Mechanica Solida Sinica》 SCIE EI 1996年第2期95-103,共9页
Based on Arnoldi's method, a version of generalized Arnoldi algorithm has been developed for the reduction of gyroscopic eigenvalue problems. By utilizing the skew symmetry of system matrix, a very simple recurren... Based on Arnoldi's method, a version of generalized Arnoldi algorithm has been developed for the reduction of gyroscopic eigenvalue problems. By utilizing the skew symmetry of system matrix, a very simple recurrence scheme, named gyroscopic Arnoldi reduction algorithm has been obtained, which is even simpler than the Lanczos algorithm for symmetric eigenvalue problems. The complex number computation is completely avoided. A restart technique is used to enable the reduction algorithm to have iterative characteristics. It has been found that the restart technique is not only effective for the convergence of multiple eigenvalues but it also furnishes the reduction algorithm with a technique to check and compute missed eigenvalues. By combining it with the restart technique, the algorithm is made practical for large-scale gyroscopic eigenvalue problems. Numerical examples are given to demonstrate the effectiveness of the method proposed. 展开更多
关键词 gyroscopic eigenvalue problem skew symmetry Arnoldi reduction algorithm restart technique
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Heuristic Reduction Algorithm Based on Pairwise Positive Region
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作者 祁立 刘玉树 《Journal of Beijing Institute of Technology》 EI CAS 2007年第3期295-299,共5页
To guarantee the optimal reduct set, a heuristic reduction algorithm is proposed, which considers the distinguishing information between the members of each pair decision classes. Firstly the pairwise positive region ... To guarantee the optimal reduct set, a heuristic reduction algorithm is proposed, which considers the distinguishing information between the members of each pair decision classes. Firstly the pairwise positive region is defined, based on which the pairwise significance measure is calculated between the members of each pair classes. Finally the weighted pairwise significance of attribute is used as the attribute reduction criterion, which indicates the necessity of attributes very well. By introducing the noise tolerance factor, the new algorithm can tolerate noise to some extent. Experimental results show the advantages of our novel heuristic reduction algorithm over the traditional attribute dependency based algorithm. 展开更多
关键词 rough set pairwise positive region heuristic reduction algorithm
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A POTENTIAL REDUCTION ALGORITHM FOR LINEARLY CONSTRAINED CONVEX PROGRAMMING
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作者 Liang XimingCollege of Information Science & Engineering,Central South Univ.,Changsha 410083. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第4期439-445,共7页
A potential reduction algorithm is proposed for optimization of a convex function subject to linear constraints.At each step of the algorithm,a system of linear equations is solved to get a search direction and the Ar... A potential reduction algorithm is proposed for optimization of a convex function subject to linear constraints.At each step of the algorithm,a system of linear equations is solved to get a search direction and the Armijo's rule is used to determine a stepsize.It is proved that the algorithm is globally convergent.Computational results are reported. 展开更多
关键词 Potential reduction algorithm linearly constrained convex programming global convergence numerical experiments.
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Unsupervised Quick Reduct Algorithm Using Rough Set Theory 被引量:1
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作者 C. Velayutham K. Thangavel 《Journal of Electronic Science and Technology》 CAS 2011年第3期193-201,共9页
Feature selection (FS) is a process to select features which are more informative. It is one of the important steps in knowledge discovery. The problem is that not all features are important. Some of the features ma... Feature selection (FS) is a process to select features which are more informative. It is one of the important steps in knowledge discovery. The problem is that not all features are important. Some of the features may be redundant, and others may be irrelevant and noisy. The conventional supervised FS methods evaluate various feature subsets using an evaluation function or metric to select only those features which are related to the decision classes of the data under consideration. However, for many data mining applications, decision class labels are often unknown or incomplete, thus indicating the significance of unsupervised feature selection. However, in unsupervised learning, decision class labels are not provided. In this paper, we propose a new unsupervised quick reduct (QR) algorithm using rough set theory. The quality of the reduced data is measured by the classification performance and it is evaluated using WEKA classifier tool. The method is compared with existing supervised methods and the result demonstrates the efficiency of the proposed algorithm. 展开更多
关键词 Index Terms--Data mining rough set supervised and unsupervised feature selection unsupervised quick reduct algorithm.
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UNIFYING REPRESENTATION OF BZIER CURVE AND GENERALIZED BALL CURVES 被引量:14
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作者 Wu HongyiDept. ofMath. and Mech., HefeiUniv. of Technology,Hefei230009. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2000年第1期109-121,共13页
This paper presents two new families of the generalized Ball curves which include the Be ′zier curve, the generalized Ball curves defined by Wang and Said independently and some intermediate curves. The relati... This paper presents two new families of the generalized Ball curves which include the Be ′zier curve, the generalized Ball curves defined by Wang and Said independently and some intermediate curves. The relative degree elevation and reduction schemes, recursive algorithms and the Bernstein\|Be ′zier representation are also given. 展开更多
关键词 Be'zier curve generalized Ballcurve degree elevation and reduction recursive algorithm .
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THE PRIMAL-DUAL POTENTIAL REDUCTION ALGORITHM FOR POSITIVE SEMI-DEFINITE PROGRAMMING
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作者 Si-ming Huang(Institute of Policy and Management, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, Beijing 100080, China) 《Journal of Computational Mathematics》 SCIE CSCD 2003年第3期339-346,共8页
In this paper we introduce a primal-dual potential reduction algorithm for positive semi-definite programming. Using the symetric preserving scalings for both primal and dual interior matrices, we can construct an alg... In this paper we introduce a primal-dual potential reduction algorithm for positive semi-definite programming. Using the symetric preserving scalings for both primal and dual interior matrices, we can construct an algorithm which is very similar to the primal-dual potential reduction algorithm of Huang and Kortanek [6] for linear programming. The complexity of the algorithm is either O(nlog(X0 · S0/ε) or O(nlog(X0· S0/ε) depends on the value of ρ in the primal-dual potential function, where X0 and S0 is the initial interior matrices of the positive semi-definite programming. 展开更多
关键词 Positive semi-definite programming Potential reduction algorithms Complexity.
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F[x]-lattice basis reduction algorithm and multisequence synthesis 被引量:4
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作者 王丽萍 祝跃飞 《Science in China(Series F)》 2001年第5期321-328,共8页
By means of F[x]-lattice basis reduction algorithm, a new algorithm is presented for synthesizing minimum length linear feedback shift registers (or minimal polynomials) for the given mul-tiple sequences over a field ... By means of F[x]-lattice basis reduction algorithm, a new algorithm is presented for synthesizing minimum length linear feedback shift registers (or minimal polynomials) for the given mul-tiple sequences over a field F. Its computational complexity is O(N2) operations in F where N is the length of each sequence. A necessary and sufficient condition for the uniqueness of minimal polynomi-als is given. The set and exact number of all minimal polynomials are also described when F is a finite field. 展开更多
关键词 multisequence shift-register synthesis F[x]-lattice basis reduction algorithm reduced basis normal reduced basis.
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Variable-fidelity optimization with design space reduction 被引量:2
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作者 Mohammad Kashif Zahir Gao Zhenghong 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第4期841-849,共9页
Advanced engineering systems, like aircraft, are defined by tens or even hundreds of design variables. Building an accurate surrogate model for use in such high-dimensional optimization problems is a difficult task ow... Advanced engineering systems, like aircraft, are defined by tens or even hundreds of design variables. Building an accurate surrogate model for use in such high-dimensional optimization problems is a difficult task owing to the curse of dimensionality. This paper presents a new algorithm to reduce the size of a design space to a smaller region of interest allowing a more accurate surrogate model to be generated. The framework requires a set of models of different physical or numerical fidelities. The low-fidelity (LF) model provides physics-based approximation of the high-fidelity (HF) model at a fraction of the computational cost. It is also instrumental in identifying the small region of interest in the design space that encloses the high-fidelity optimum. A surrogate model is then constructed to match the low-fidelity model to the high-fidelity model in the identified region of interest. The optimization process is managed by an update strategy to prevent convergence to false optima. The algorithm is applied on mathematical problems and a two-dimen-sional aerodynamic shape optimization problem in a variable-fidelity context. Results obtained are in excellent agreement with high-fidelity results, even with lower-fidelity flow solvers, while showing up to 39% time savings. 展开更多
关键词 Airfoil optimization Curse of dimensionality Design space reduction Genetic algorithms Kriging Surrogate models Surrogate update strategies Variable fidelity
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Speckle noise reduction in digital holography with spatial light modulator and nonlocal means algorithm 被引量:3
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作者 冷俊敏 桑新柱 颜盼盼 《Chinese Optics Letters》 SCIE EI CAS CSCD 2014年第4期4-8,共5页
An integrated method based on optical and digital image processing is presented to suppress speckle in digital holography. A spatial light modulator is adopted to introduce random phases to the illuminating beam. Mult... An integrated method based on optical and digital image processing is presented to suppress speckle in digital holography. A spatial light modulator is adopted to introduce random phases to the illuminating beam. Multiple holograms are reconstructed and superimposed, and the intensity is averaged to smooth the noise. The adaptive algorithm based on the nonlocal means is designed to further suppress the speckle. The presented method is compared with other methods reduction is improved, and the proposed method is effective The experimental results show that speckle and feasible. 展开更多
关键词 ENL Speckle noise reduction in digital holography with spatial light modulator and nonlocal means algorithm SLM NLM
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Noise reduction algorithm of corrosion acoustic emission signal based on short-time fractal dimension enhancement
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作者 YU Yang ZHANG Wenwen YANG Ping 《Chinese Journal of Acoustics》 CSCD 2016年第2期167-177,共11页
The general corrosion and local corrosion of Q235 steel were tested by acoustic emission (AE) detecting system under 6% FeCl3.6H2O solution to effectively detect the corrosion acoustic emission signal from complex b... The general corrosion and local corrosion of Q235 steel were tested by acoustic emission (AE) detecting system under 6% FeCl3.6H2O solution to effectively detect the corrosion acoustic emission signal from complex background noise. The short-time fractal dimension and discrete fractional cosine transform methods are combined to reduce noise. The input SNR is 0-15 dB while corrosion acoustic emission signals being added with white noise, color noise and pink noise respectively. The results show that the output signal-to-noise ratio is improved by up to 8 dB compared with discrete cosine transform and discrete fractional cosine transform. The above-mentioned noise reduction method is of significance for the identification of corrosion induced acoustic emission signals and the evaluation of the metal remaining life. 展开更多
关键词 TIME Noise reduction algorithm of corrosion acoustic emission signal based on short-time fractal dimension enhancement
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Regular Splitting and Potential Reduction Method for Solving Quadratic Programming Problem with Box Constraints
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作者 Zi-Luan Wei(Institute of Computational Mathematics and Scientific / Engineering Computing, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, P.O. Box 2719, Beijing, 100080) 《Journal of Computational Mathematics》 SCIE CSCD 2002年第6期643-652,共10页
Presents a regular splitting and potential reduction method for solving a quadratic programming problem with box constraints. Discussion on the regular splitting and potential reduction algorithm; Complexity analysis ... Presents a regular splitting and potential reduction method for solving a quadratic programming problem with box constraints. Discussion on the regular splitting and potential reduction algorithm; Complexity analysis of the algorithm; Analysis of the complexity bound on obtaining an approximate solution. 展开更多
关键词 quadratic programming problem regular splitting potential reduction algorithm complexity analysis
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Aerodynamic multi-objective integrated optimization based on principal component analysis 被引量:10
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作者 Jiangtao HUANG Zhu ZHOU +2 位作者 Zhenghong GAO Miao ZHANG Lei YU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第4期1336-1348,共13页
Based on improved multi-objective particle swarm optimization(MOPSO) algorithm with principal component analysis(PCA) methodology, an efficient high-dimension multiobjective optimization method is proposed, which,... Based on improved multi-objective particle swarm optimization(MOPSO) algorithm with principal component analysis(PCA) methodology, an efficient high-dimension multiobjective optimization method is proposed, which, as the purpose of this paper, aims to improve the convergence of Pareto front in multi-objective optimization design. The mathematical efficiency,the physical reasonableness and the reliability in dealing with redundant objectives of PCA are verified by typical DTLZ5 test function and multi-objective correlation analysis of supercritical airfoil,and the proposed method is integrated into aircraft multi-disciplinary design(AMDEsign) platform, which contains aerodynamics, stealth and structure weight analysis and optimization module.Then the proposed method is used for the multi-point integrated aerodynamic optimization of a wide-body passenger aircraft, in which the redundant objectives identified by PCA are transformed to optimization constraints, and several design methods are compared. The design results illustrate that the strategy used in this paper is sufficient and multi-point design requirements of the passenger aircraft are reached. The visualization level of non-dominant Pareto set is improved by effectively reducing the dimension without losing the primary feature of the problem. 展开更多
关键词 Aerodynamic optimization Dimensional reduction Improved multi-objective particle swarm optimization(MOPSO) algorithm Multi-objective Principal component analysis
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