检索结果-南通市图书馆

Efficient multi-objective CMA-ES algorithm assisted by knowledge-extraction-based variable-fidelity surrogate model

Chinese Journal of Aeronautics 2023年第6期36卷 213-232页

作者： Zengcong LI kuo TIAN Shu ZHANG Bo WANG State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsDalian University of TechnologyDalian 116024China

To accelerate the multi-objective optimization for expensive engineering cases, a Knowledge-Extraction-based Variable-Fidelity Surrogate-assisted Covariance Matrix Adaptation Evolution Strategy(KE-VFS-CMA-ES) is presented. In the first part, the KE-VFS model is established. Firstly, the optimization is performed using the low-fidelity surrogate model to obtain the Low-Fidelity Non-Dominated Solutions(LF-NDS). Secondly, aiming to obtain the High-Fidelity(HF) sample points located in promising areas, the K-means clustering algorithm and the space-filling strategy are used to extract knowledge from the LF-NDS to the HF space. Finally,the KE-VFS model is established by means of the obtained HF and LF sample points. In the second part, a novel model management based on the Modified Hypervolume Improvement(MHVI) criterion and pre-screening strategy is proposed. In each generation of KE-VFS-CMA-ES, excessive candidate points are firstly generated and then calculated by the MHVI criterion to find out a few potential points, which will be evaluated by the HF model. Through the above two parts,the promising areas can be detected and the potential points can be screened out, which contributes to speeding up the optimization process twofold. Three classic benchmark functions and a time-consuming engineering case of the aerospace integrally stiffened shell are studied, and results illustrate the excellent efficiency, robustness and applicability of KE-VFS-CMA-ES compared with other four known multi-objective optimization algorithms.

关键词： Covariance matrix adaptation evolution strategy Model management Multi-objective optimization Surrogate-assisted evolutionary algorithm Variable-fidelity surrogate model

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

New Soliton-like Solutions for Combined KdV and mKdV Equation

引用

Communications in Theoretical Physics 2005年第4期43卷 615-616页

作者： ZHAOQiang LIUShi-kuo FUZun-Tao SchoolofPhysics PekingUniversityBeijing100871China

By the application of the extended tanh method and the symbolic computation system Mathematica, new soliton-like solutions are obtained for the combined KdV and mKdV (KdV-mKdV) equation.

关键词： extended tanh method KdV-mKdV equation soliton-like solutions

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Theoretical Calculation of Energy Spectrum of YGG:Cr^(3+)and Thermal Shifts of Its R-Lines

引用

Communications in Theoretical Physics 2009年第5期51卷 914-918页

作者： YANG kuo ZHANG Ji-Ping College of Physical Science and Technology Sichuan University Chengdu 610065 China Physical Department of A＇ba Teachers College Wenchuan 623000 China

With the strong-field scheme and trigonal bases, the complete d3 energy matrix in a trigonally distorted cubic-field has been constructed. By diagonalizing this matrix, the energy spectrum of YGG：Cr^3＋ at normal pressure and low temperature has been calculated. The g factor of the ground-state has been evaluated in terms of the energy spectrum. At the same time, by using the wavefunctions obtained from diagonalizing the complete d^3 energy matrix and Thermal Shifts theory, we calculate the thermal shifts of the sharp lines of YGG：Cr^3＋ and determine the relevant parameters. The calculated results are all in good agreement with the optical-spectrum and EPR experimental data. It is demonstrated that the obtained wavefunctions and the values of parameters are reasonable.

关键词： optical propenty electron-phonon interaction electronic structure thermal shift g factor

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Solving Nonlinear Wave Equations by Elliptic Equation

引用

Communications in Theoretical Physics 2003年第5期39卷 531-536页

作者： FUZun-Tao LIUShi-Da LIUShi-kuo SchoolofPhysics PekingUniversityBeijing1000871China StateKeyLaboratoryforTurbulenceandComplexSystem PekingUniversityBeijing100871China SchoolofPhysics PekingUniversityBeijing100871China StateKeyLaboratoryforTurbulenceandComplexSystem PekingUniversityBeijing100871China SchoolofPhysics PekingUniversityBeijing100871China

The elliptic equation is taken as a transformation and applied to solve nonlinear wave equations. It is shown that this method is more powerful to give more kinds of solutions, such as rational solutions, solitary wav... 详细信息

关键词： elliptic equation Jacobi elliptic function nonlinear equation periodic wave solution

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A Normal Contact Stiffness Model of Joint Surface Based on Fractal Theory

引用

Computer Modeling in Engineering & Sciences 2019年第6期119卷 459-480页

作者： kuo Xu Yuan Yuan Lihua Zhang Xi’An University of Technology Xi’An710048China

Based on the fractal theory,a normal contact stiffness model is *** the model,the asperity is initially in elastic deformation under contact *** the interference is increased,a transition from elastic to elastoplastic to full plastic deformation occurs in this *** critical elastic interference,the first elastoplastic critical interference and the second elastoplastic critical interference are *** to the truncated asperity size distribution function,the relations between the total normal contact stiffness and the total contact load are *** results show the total normal contact stiffness depends on the range of frequency indexes of *** normal contact stiffness in elastic deformation is major contribution to the total normal contact *** the first six frequency indexes are less than the critical elastic frequency index,the dimensionless load-stiffness relation approximately isF^*r^(K^*r)^*** the initial frequency index is greater than the critical elastic frequency index,the dimensionless load-stiffness relation approximately isF^*r^K^**** comparison between the theoretical results and the experimental results indicates that the theoretical results are consistent with the experimental data;therefore,the present fractal model of contact stiffness is reasonable.

关键词： Normal contact stiffness asperity frequency index the joint surface

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Improved Dual-image Quality with Reversible Data Hiding Using Translocation and Switching Strategy

引用

Computer Systems Science & Engineering 2023年第2期44卷 1551-1566页

作者： Chin-Feng Lee kuo-Chung Chan Department of Information Management Chaoyang University of TechnologyTaichung41349Taiwan

Dual-image reversible data hiding(RDH)is a technique for hiding important *** technology can be used to safely deliver secret mes-sages to the recipient through dual images in an open network without being easily *** recipient of the image must receive the two stego-images before the secret message can be completely *** is one of the main advantages of data hiding technology;to increase the imperceptibility,the quality requirements of the stego-images are relatively important.A dual ste-ganographic image RDH method,called a DS-CF scheme that can achieve a bet-ter steganographic image quality using the center folding(CF)*** this paper,we developed a translocation and switching strategy(TaS)to shorten the distances between the stego-pixel coordinates and the cover pixel coordinates after information being *** with the DS-CF scheme,our proposed DS-TaS scheme can effectively improve the quality of the steganographic images at the same level of embedding *** experimental results show that the PSNR of our DS-TaS scheme at k=1 was 55.66 dB,which is an increase of 1.5 dB,and is 51.43 dB for k=2,46.66 dB for k=3,and 40.91 dB for k=*** addition,the PSNR values of the stego images was increased by 1.5,0.29,0.29,and 0.19 dB,*** shows that our proposed dual-image RDH method can optimize the visual quality of the stego-images and is better than many other dual-image RDH techniques.

关键词： Information hiding reversible data hiding(RDH) dual-image RDH center folding(CF)strategy

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

New Exact Solutions to NLS Equation and Coupled NLS Equations

引用

Communications in Theoretical Physics 2004年第2期41卷 189-194页

作者： FUZun-Tao LIUShi-Da LIUShi-kuo SchoolofPhysics PekingUniversityBeijing100871China

A transformation is introduced on the basis of the projective Riccati equations, and it is applied as an intermediate in expansion method to solve nonlinear Schrǒdinger (NLS) equation and coupled NLS equations. Manykinds of envelope travelling wave solutions including envelope solitary wave solution are obtained, in which some arefound for the first time.

关键词： projective Riccati equations NLS equation envelope travelling wave solution envelope solitary wave solution

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Applications of Elliptic Equation to Nonlinear Coupled Systems

引用

Communications in Theoretical Physics 2003年第3X期40卷 285-292页

作者： FUZun-Tao LIUShi-Da LIUShi-kuo SchoolofPhysics PekingUniversityBeijing100871China

The elliptic equation is taken as a transformation and applied to solve nonlinear coupled systems. It is shown that this method is more powerful to give more kinds of solutions, such as rational solutions, solitary wave solutions, periodic wave solutions and so on, so this method can be taken as a unified method in solving nonlinear coupled systems.

关键词：椭圆型方程雅各比椭圆型函数非线性耦合系统周期波解孤波解

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

MULTIPLICATIVE PERTURBATIONS OF LOCAL α-TIMES INTEGRATED C-SEMIGROUPS

引用

Acta Mathematica Scientia 2017年第3期37卷 877-888页

作者： Nai-Sher YEH Chung-Cheng kuo Department of Mathematics Fu Jen Catholic University New Taipei City Taiwan China

We establish some left and right multiplicative perturbations of a local α-timesintegrated C-semigroup S（·） on a complex Banach space X with non-densely defined genera- tor, which can be applied to obtain some additive perturbation results concerning S（·）. Some growth conditions of the perturbations of S（·） are also established.

关键词： Integrated C-semigroup generator abstract Cauchy problem perturbation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Seven-step total synthesis of α-cyclopiazonic acid

引用

Chinese Chemical Letters 2020年第2期31卷 401-403页

作者： Shibin Shi kuo Yuan Yanxing Jia State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China

A seven-step total synthesis of α-cyclopiazonic acid is reported from a commercially available *** feature of the work is the rapid formation of tetracyclic skeleton via a bioinspired [3+2] annulation to form the C/D... 详细信息

关键词： Indole alkaloids Total synthesis Cascade cyclization Natural products

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：