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Precise integration method for a class of singular two-point boundary value problems 被引量:2
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作者 Wen-Zhi Zhang Pei-Yan Huang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第2期233-240,共8页
In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value problems.Firstly,by employing the met... In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value problems.Firstly,by employing the method of variable coefficient dimensional expanding,the non-homogeneous ordinary differential equations(ODEs) are transformed into homogeneous ODEs.Then the interval is divided evenly,and the transfer matrix in every subinterval is worked out using the high order multiple perturbation method,and a set of algebraic equations is given in the form of matrix by the precise integration relation for each segment,which is worked out by the reduction method.Finally numerical examples are elaboratedd to validate the present method. 展开更多
关键词 Singular two point boundary value problem Precise integration method High order multiple perturbation method Reduction method
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Isogeometric Boundary Element Analysis for 2D Transient Heat Conduction Problem with Radial Integration Method 被引量:3
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作者 Leilei Chen Kunpeng Li +3 位作者 Xuan Peng Haojie Lian Xiao Lin Zhuojia Fu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第1期125-146,共22页
This paper presents an isogeometric boundary element method(IGABEM)for transient heat conduction analysis.The Non-Uniform Rational B-spline(NURBS)basis functions,which are used to construct the geometry of the structu... This paper presents an isogeometric boundary element method(IGABEM)for transient heat conduction analysis.The Non-Uniform Rational B-spline(NURBS)basis functions,which are used to construct the geometry of the structures,are employed to discretize the physical unknowns in the boundary integral formulations of the governing equations.Bezier extraction technique is employed to accelerate the evaluation of NURBS basis functions.We adopt a radial integration method to address the additional domain integrals.The numerical examples demonstrate the advantage of IGABEM in dimension reduction and the seamless connection between CAD and numerical analysis. 展开更多
关键词 Isogeometric analysis NURBS boundary element method heat conduction radial integration method
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CAUCHY TYPE INTEGRALS AND A BOUNDARY VALUE PROBLEM IN A COMPLEX CLIFFORD ANALYSIS
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作者 曹南斌 李尊凤 +1 位作者 杨贺菊 乔玉英 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期369-385,共17页
Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quan... Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quantum mechanics and value problems.In this paper,we first give the definition of a quasi-Cauchy type integral in complex Clifford analysis,and get the Plemelj formula for it.Second,we discuss the H?lder continuity for the Cauchy-type integral operators with values in a complex Clifford algebra.Finally,we prove the existence of solutions for a class of linear boundary value problems and give the integral representation for the solution. 展开更多
关键词 Clifford analysis Cauchy type integral Plemelj formula Holder continuous boundary value problems
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Resolving Domain Integral Issues in Isogeometric Boundary Element Methods via Radial Integration:A Study of Thermoelastic Analysis 被引量:1
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作者 Shige Wang Zhongwang Wang +3 位作者 Leilei Chen Haojie Lian Xuan Peng Haibo Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第8期585-604,共20页
The paper applied the isogeometric boundary element method(IGABEM)to thermoelastic problems.The Non-Uniform Rational B-splines(NURBS)used to construct geometric models are employed to discretize the boundary integral ... The paper applied the isogeometric boundary element method(IGABEM)to thermoelastic problems.The Non-Uniform Rational B-splines(NURBS)used to construct geometric models are employed to discretize the boundary integral formulation of the governing equation.Due to the existence of thermal stress,the domain integral term appears in the boundary integral equation.We resolve this problem by incorporating radial integration method into IGABEM which converts the domain integral to the boundary integral.In this way,IGABEM can maintain its advantages in dimensionality reduction and more importantly,seamless integration of CAD and numerical analysis based on boundary representation.The algorithm is verified by numerical examples. 展开更多
关键词 Isogeometric analysis NURBS boundary element method THERMOELASTIC radial integration method
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Discourse Analysis of packages in Chinese Cross Talk from Conceptual Integration Theory
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作者 翟莉 《海外英语》 2017年第3期233-234,共2页
Packages in Chinese cross talk are the origin of cross talk humor.By using the literature investigation method,the paper find the effect of humor when create the packages and unpack the packages,which is the process t... Packages in Chinese cross talk are the origin of cross talk humor.By using the literature investigation method,the paper find the effect of humor when create the packages and unpack the packages,which is the process that audiences construct mental spaces and create mappings between mental spaces,but the detail process of mental spaces and the mappings of mental spaces is uncertain.Thus,the paper uses literature investigation and illustration as the main research methods.This paper means to make a better understanding of the humor of cross talk and can help to create more humor discourse. 展开更多
关键词 cross talk PACKAGES conceptual integration theory mental spaces MAPPING
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SOLUTION OF ARBITRARY CROSS-SECTION WAVEGUIDE USING METHOD OF EIGEN WEIGHTED BOUNDARY INTEGRAL EQUATION
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作者 祝雷 章文勋 《Journal of Electronics(China)》 1990年第3期258-262,共5页
Based on the second kind of Green’s identity,a boundary integral equation forarbitrary cross-section waveguide is transformed to a system of linear homogeneous algebraicequations by means of expansion of boundary bas... Based on the second kind of Green’s identity,a boundary integral equation forarbitrary cross-section waveguide is transformed to a system of linear homogeneous algebraicequations by means of expansion of boundary bases and by using the eigenfunctions of a fictitiousregular boundary as weighting functions,which corresponds to less algebraic equations than BEMand simpler coefficients than the modified BEM.The numerical results for some typical metallicwaveguides are given by using the method of eigen-weighted boundary integral equation,and theyare accurate enough with fast convergence. 展开更多
关键词 boundary integral METHOD Metallic WAVEGUIDE Eigenvalue PROBLEM CUT-OFF WAVENUMBER boundary value PROBLEM
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TWO DIMENSIONAL FLOW QUANTITATIVE VISUALIZATION BY THE HYBRID METHOD OF FLOW BIREFRINGENCE AND BOUNDARY INTEGRATION
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作者 陈瑜海 贾有权 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1992年第1期88-92,共5页
Flow birefringent method and its data processing was reviewed and a new hybrid method of flow birefringence and boundary integration was introduced. The basic equations and boundary conditions suitable to the hybrid m... Flow birefringent method and its data processing was reviewed and a new hybrid method of flow birefringence and boundary integration was introduced. The basic equations and boundary conditions suitable to the hybrid method were derived, and a comparison of the hybrid and other classical methods was given. Finally as an example, the flow in a step converging tube was analyzed by the given method. 展开更多
关键词 flow birefringence hybrid method boundary integration
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Stability conditions of explicit integration algorithms when using 3D viscoelastic artificial boundaries
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作者 Bao Xin Liu Jingbo +2 位作者 Li Shutao Wang Fei Lu Xihuan 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2022年第4期929-945,共17页
Viscoelastic artificial boundaries are widely adopted in numerical simulations of wave propagation problems.When explicit time-domain integration algorithms are used,the stability condition of the boundary domain is s... Viscoelastic artificial boundaries are widely adopted in numerical simulations of wave propagation problems.When explicit time-domain integration algorithms are used,the stability condition of the boundary domain is stricter than that of the internal region due to the influence of the damping and stiffness of an viscoelastic artificial boundary.The lack of a clear and practical stability criterion for this problem,however,affects the reasonable selection of an integral time step when using viscoelastic artificial boundaries.In this study,we investigate the stability conditions of explicit integration algorithms when using three-dimensional(3D)viscoelastic artificial boundaries through an analysis method based on a local subsystem.Several boundary subsystems that can represent localized characteristics of a complete numerical model are established,and their analytical stability conditions are derived from and further compared to one another.The stability of the complete model is controlled by the corner regions,and thus,the global stability criterion for the numerical model with viscoelastic artificial boundaries is obtained.Next,by analyzing the impact of different factors on stability conditions,we recommend a stability coefficient for practically estimating the maximum stable integral time step in the dynamic analysis when using 3D viscoelastic artificial boundaries. 展开更多
关键词 explicit time domain integration viscoelastic artificial boundary numerical stability local subsystem transfer matrix
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Crossing Boundaries
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作者 Francis L.Sackitey 《ChinAfrica》 2012年第1期22-23,共2页
GHANA'S discovery of oil on its border with Cote d'Ivoire is testing the long-standing relationship between the two nations. The long running dispute over oil has led to Cote d'Ivoire's Director General of Hydroca... GHANA'S discovery of oil on its border with Cote d'Ivoire is testing the long-standing relationship between the two nations. The long running dispute over oil has led to Cote d'Ivoire's Director General of Hydrocarbons and Petroci unveiling a new maritime border with Ghana in November 2011, that includes some of the massive oil wealth in the western region, Ghana's Jubilee oil fields, as reported by Upstream, a global oil and gas publication. 展开更多
关键词 crossing Boundaries NATION
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Cross -field Integration of Language Acquisition with Meme Theory
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作者 Jiang Xiao 《学术界》 CSSCI 北大核心 2014年第7期296-302,共7页
In strengthening the multi-disciplinary and multi-angle cooperation,the theoretical analysis of linguistics can be improved to a newlevel and also the study of language acquisition can be expanded to a wilder field of... In strengthening the multi-disciplinary and multi-angle cooperation,the theoretical analysis of linguistics can be improved to a newlevel and also the study of language acquisition can be expanded to a wilder field of view. The secret for the pedagogy of performing another culture to be successful lies in integrating with the theoretical knowledge in other disciplines and fields and promoting the development of the second language pedagogy to a broader space. In this process,the"meme theory"in the field of biology is a theoretical method absorbed and very outstandingly implemented by the pedagogy of performing another culture,so it is worth borrowing and introducing and also is of great significance in language acquisition. 展开更多
关键词 知识整合 语言学 教学发展 生物学领域 教学方法 文化
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Integration system research and development for three-dimensional laser scanning information visualization in goaf 被引量:1
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作者 罗周全 黄俊杰 +2 位作者 罗贞焱 汪伟 秦亚光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1985-1994,共10页
An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, clo... An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable. 展开更多
关键词 GOAF laser scanning visualization integration system 1 Introduction The goaf formed through underground mining of mineral resources is one of the main disaster sources threatening mine safety production [1 2]. Effective implementation of goaf detection and accurate acquisition of its spatial characteristics including the three-dimensional morphology the spatial position as well as the actual boundary and volume are important basis to analyze predict and control disasters caused by goaf. In recent years three-dimensional laser scanning technology has been effectively applied in goaf detection [3 4]. Large quantities of point cloud data that are acquired for goaf by means of the three-dimensional laser scanning system are processed relying on relevant engineering software to generate a three-dimensional model for goaf. Then a general modeling analysis and processing instrument are introduced to perform subsequent three-dimensional analysis and calculation [5 6]. Moreover related development is also carried out in fields such as three-dimensional detection and visualization of hazardous goaf detection and analysis of unstable failures in goaf extraction boundary acquisition in stope visualized computation of damage index aided design for pillar recovery and three-dimensional detection
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Linkage analysis and integrated software GAPL for pure-line populations derived from four-way and eight-way crosses 被引量:6
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作者 Luyan Zhang Lei Meng Jiankang Wang 《The Crop Journal》 SCIE CAS CSCD 2019年第3期283-293,共11页
Pure lines derived from multiple parents provide abundant variation for genetic study.However,efficient genetic analysis methods and user-friendly software are still lacking.In this study, we developed linkage analysi... Pure lines derived from multiple parents provide abundant variation for genetic study.However,efficient genetic analysis methods and user-friendly software are still lacking.In this study, we developed linkage analysis methods and integrated analysis software for pure-line populations derived from four-way and eight-way crosses.First, polymorphic markers are classified into different categories according to the number of identifiable alleles in the inbred parents.Expected genotypic probability is then derived for each pair of complete markers, and based on them a maximum likelihood estimate(MLE) of recombination frequency is calculated.An EM algorithm is proposed for calculating recombination frequencies in scenarios that at least one marker is incomplete.A linkage map can thus be constructed using estimated recombination frequencies.We describe a software package called GAPL for recombination frequency estimation and linkage map construction in multi-parental pure-line populations.Both simulation studies and results from a reported four-way cross recombinant inbred line population demonstrate that the proposed method and software can build more accurate linkage maps in shorter times than other published software packages.The GAPL software is freely available from www.isbreeding.net and can also be used for QTL mapping in multi-parental populations. 展开更多
关键词 Pure lines Four-way cross Eight-way cross Recombination frequency estimation integrated software
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Existence of Positive Solutions for Systems of Second-order Nonlinear Singular Differential Equations with Integral Boundary Conditions on Infinite Interval 被引量:18
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作者 LI Yao-hong 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第1期55-64,共10页
By using cone theory and the MSnch fixed theorem combined with a monotone iterative technique, we investigate the existence of positive solutions for systems of second- order nonlinear singular differential equations ... By using cone theory and the MSnch fixed theorem combined with a monotone iterative technique, we investigate the existence of positive solutions for systems of second- order nonlinear singular differential equations with integral boundary conditions on infinite interval and establish the existence theorem of positive solutions and iterative sequence for approximating the positive solutions. The results in this paper improve some known results. 展开更多
关键词 boundary value problems positive solutions integral boundary conditions theMSnch fixed point theorem
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On the Devonian-Carboniferous Boundary in Neritic Facies Areas of South China:A Viewpoint of Integrated StratigraPhy 被引量:5
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作者 Wang XunlianDepartment of Geology and Mineral Resources, China University of Geoxciences, Beijing 100083 《Journal of Earth Science》 SCIE CAS CSCD 1995年第2期68-75,共8页
Biostratigraphical data indicate that in the neritic facies areas of South China, the Devonian -Carboniferous boundary (DCB), matching the boundary between conodont Siphonodella praesulcata zone and S. sulcata zone, s... Biostratigraphical data indicate that in the neritic facies areas of South China, the Devonian -Carboniferous boundary (DCB), matching the boundary between conodont Siphonodella praesulcata zone and S. sulcata zone, should be drawn between rugose coral Cystophrentis zone and Pseudouralina zone, i.e. the Cystophrentis\ Pseudouralina inter val-zone. The top of the sea level fall event bed near the DCB is lower than the boundary between S. praesulcata and S. sulcata zones, but higher than the top of the Cysto phrentis zone. Sequence stratigraphical study shows that the sea level fall event bed near the DCB constitutes the shelf margin system tract (SMST) of a depositional sequence (SQ1) in both neritic and pelagic facies areas. The top surfaces of SMST of SQ1 is slightly lower than the base of S. sulcata zone in the pelagic facies areas. In neritic facies areas of South China, therefore, the Devonian - Carboniferous boundary is marked by the most distinct transgressive surface within the Cystophrentis\ Pseudouralina interval-zone, i.e. the base of the TST of SQ1. This boundary coincides with the top surface of the event bed resulted from the eustatic fall, and approximately corresponds to the base of Pseudouralina assemblage zone. 展开更多
关键词 boundary Devonian and Carboniferous integrated stratigraphy eventstratigraphy sequence stratigraphy BIOSTRATIGRAPHY South China.
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Boundary properties for several singular integral operators in real Clifford analysis 被引量:7
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作者 YANG He-ju XIE Yong-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第3期349-358,共10页
On the basis of the Cauchy integral formulas for regular and biregular functions, we define some Cauchy-type singular integral operators. Then we discuss the Holder continuous property of some singular integral operat... On the basis of the Cauchy integral formulas for regular and biregular functions, we define some Cauchy-type singular integral operators. Then we discuss the Holder continuous property of some singular integral operators with one integral variable. Then we divide a singular integral operator with two variables into three parts and prove its Holder continuous property on the boundary. 展开更多
关键词 Singular integral operator Holder continuous function boundary property.
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FRACTIONAL ORDER BOUNDARY VALUE PROBLEM WITH INTEGRAL BOUNDARY CONDITIONS INVOLVING PETTIS INTEGRAL 被引量:5
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作者 Hussein A.H. Salem 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期661-672,共12页
In this article, we investigate the existence of Pseudo solutions for some fractional order boundary value problem with integral boundary conditions in the Banach space of continuous function equipped with its weak to... In this article, we investigate the existence of Pseudo solutions for some fractional order boundary value problem with integral boundary conditions in the Banach space of continuous function equipped with its weak topology. The class of such problems constitute a very interesting and important class of problems. They include two, three, multi-point and nonlocal boundary-value problems as special cases. In our investigation, the right hand side of the above problem is assumed to be Pettis integrable function. To encompass the full scope of this article, we give an example illustrating the main result. 展开更多
关键词 Fractional calculus Pseudo solution boundary value problem Pettis integrals
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Response Sensitivity Analysis of the Dynamic Milling Process Based on the Numerical Integration Method 被引量:4
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作者 DING Ye ZHU Limin +1 位作者 ZHANG Xiaojian DING Han 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第5期940-946,共7页
As one of the bases of gradient-based optimization algorithms, sensitivity analysis is usually required to calculate the derivatives of the system response with respect to the machining parameters. The most widely use... As one of the bases of gradient-based optimization algorithms, sensitivity analysis is usually required to calculate the derivatives of the system response with respect to the machining parameters. The most widely used approaches for sensitivity analysis are based on time-consuming numerical methods, such as finite difference methods. This paper presents a semi-analytical method for calculation of the sensitivity of the stability boundary in milling. After transforming the delay-differential equation with time-periodic coefficients governing the dynamic milling process into the integral form, the Floquet transition matrix is constructed by using the numerical integration method. Then, the analytical expressions of derivatives of the Floquet transition matrix with respect to the machining parameters are obtained. Thereafter, the classical analytical expression of the sensitivity of matrix eigenvalues is employed to calculate the sensitivity of the stability lobe diagram. The two-degree-of-freedom milling example illustrates the accuracy and efficiency of the proposed method. Compared with the existing methods, the unique merit of the proposed method is that it can be used for analytically computing the sensitivity of the stability boundary in milling, without employing any finite difference methods. Therefore, the high accuracy and high efficiency are both achieved. The proposed method can serve as an effective tool for machining parameter optimization and uncertainty analysis in high-speed milling. 展开更多
关键词 MILLING STABILITY sensitivity of the stability boundary numerical integration method
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EXISTENCE AND UNIQUENESS OF SOLUTIONS FOR NONLINEAR FRACTIONAL DIFFERENTIAL EQUATIONS WITH NON-SEPARATED TYPE INTEGRAL BOUNDARY CONDITIONS 被引量:6
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作者 Bashir Ahmad Juan J. Nieto Ahmed Alsaedi 《Acta Mathematica Scientia》 SCIE CSCD 2011年第6期2122-2130,共9页
In this paper, we study a boundary value problem of nonlinear fractional dif- ferential equations of order q (1 〈 q 〈 2) with non-separated integral boundary conditions. Some new existence and uniqueness results a... In this paper, we study a boundary value problem of nonlinear fractional dif- ferential equations of order q (1 〈 q 〈 2) with non-separated integral boundary conditions. Some new existence and uniqueness results are obtained by using some standard fixed point theorems and Leray-Schauder degree theory. Some illustrative examples are also presented. We extend previous results even in the integer case q = 2. 展开更多
关键词 fractional differential equations non-separated integral boundary conditions contraction principle Krasnoselskii's fixed point theorem LeraySchauder degree
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A Novel Bat Algorithm based on Cross Boundary Learning and Uniform Explosion Strategy 被引量:2
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作者 YONG Jia-shi HE Fa-zhi +1 位作者 LI Hao-ran ZHOU Wei-qing 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2019年第4期480-502,共23页
Population-based algorithms have been used in many real-world problems.Bat algorithm(BA)is one of the states of the art of these approaches.Because of the super bat,on the one hand,BA can converge quickly;on the other... Population-based algorithms have been used in many real-world problems.Bat algorithm(BA)is one of the states of the art of these approaches.Because of the super bat,on the one hand,BA can converge quickly;on the other hand,it is easy to fall into local optimum.Therefore,for typical BA algorithms,the ability of exploration and exploitation is not strong enough and it is hard to find a precise result.In this paper,we propose a novel bat algorithm based on cross boundary learning(CBL)and uniform explosion strategy(UES),namely BABLUE in short,to avoid the above contradiction and achieve both fast convergence and high quality.Different from previous opposition-based learning,the proposed CBL can expand the search area of population and then maintain the ability of global exploration in the process of fast convergence.In order to enhance the ability of local exploitation of the proposed algorithm,we propose UES,which can achieve almost the same search precise as that of firework explosion algorithm but consume less computation resource.BABLUE is tested with numerous experiments on unimodal,multimodal,one-dimensional,high-dimensional and discrete problems,and then compared with other typical intelligent optimization algorithms.The results show that the proposed algorithm outperforms other algorithms. 展开更多
关键词 Optimization BAT algorithm cross boundary LEARNING UNIFORM explosion STRATEGY
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THE BOUNDARY INTEGRAL METHOD FOR THE HELMHOLTZ EQUATION WITH CRACKS INSIDE A BOUNDED DOMAIN 被引量:3
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作者 郭军 范丽丽 严国政 《Acta Mathematica Scientia》 SCIE CSCD 2015年第3期539-551,共13页
We consider a kind of scattering problem by a crack F that is buried in a bounded domain D, and we put a point source inside the domain D. This leads to a mixed boundary value problem to the Helmholtz equation in the ... We consider a kind of scattering problem by a crack F that is buried in a bounded domain D, and we put a point source inside the domain D. This leads to a mixed boundary value problem to the Helmholtz equation in the domain D with a crack Г. Both sides of the crack F are given Dirichlet-impedance boundary conditions, and different boundary condition (Dirichlet, Neumann or Impedance boundary condition) is set on the boundary of D. Applying potential theory, the problem can be reformulated as a system of boundary integral equations. We establish the existence and uniqueness of the solution to the system by using the Fredholm theory. 展开更多
关键词 boundary integral equation Helmholtz equation Fredholm theory
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