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Data-driven prediction of dimensionless quantities for semi-infinite target penetration by integrating machine-learning and feature selection methods
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作者 Qingqing Chen Xinyu Zhang +2 位作者 Zhiyong Wang Jie Zhang Zhihua Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期105-124,共20页
This study employs a data-driven methodology that embeds the principle of dimensional invariance into an artificial neural network to automatically identify dominant dimensionless quantities in the penetration of rod ... This study employs a data-driven methodology that embeds the principle of dimensional invariance into an artificial neural network to automatically identify dominant dimensionless quantities in the penetration of rod projectiles into semi-infinite metal targets from experimental measurements.The derived mathematical expressions of dimensionless quantities are simplified by the examination of the exponent matrix and coupling relationships between feature variables.As a physics-based dimension reduction methodology,this way reduces high-dimensional parameter spaces to descriptions involving only a few physically interpretable dimensionless quantities in penetrating cases.Then the relative importance of various dimensionless feature variables on the penetration efficiencies for four impacting conditions is evaluated through feature selection engineering.The results indicate that the selected critical dimensionless feature variables by this synergistic method,without referring to the complex theoretical equations and aiding in the detailed knowledge of penetration mechanics,are in accordance with those reported in the reference.Lastly,the determined dimensionless quantities can be efficiently applied to conduct semi-empirical analysis for the specific penetrating case,and the reliability of regression functions is validated. 展开更多
关键词 Data-driven dimensional analysis PENETRATION semi-infinite metal target Dimensionless numbers Feature selection
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Interaction between many parallel screw dislocations and a semi-infinite crack in a magnetoelectroelastic solid 被引量:5
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作者 吕鑫 刘官厅 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第7期393-396,共4页
Based on the fundamental equations of magnetoelectroelastic material and the analytic theory, and using the Muskhelishvili-introduced well-known elastic techniques combined with the superposition principle, the closed... Based on the fundamental equations of magnetoelectroelastic material and the analytic theory, and using the Muskhelishvili-introduced well-known elastic techniques combined with the superposition principle, the closed form solution of the generalized stress field of the interaction between many parallel screw dislocations and a semi-infinite crack in an infinite magnetoelectroelastic solid is obtained, on the assumption that the surface of the crack is impermeable electrically and magnetically. Besides, the Peach-Koehler formula of n parallel screw dislocations is given. Numerical examples show that the generalized stress varies with the position of point z and is related to the material constants. The results indicate that the stress concentration occurs at the dislocation core and the tip of the crack. The result of interaction makes the system stay in a lower energy state. 展开更多
关键词 parallel screw dislocations semi-infinite crack magnetoelectroelastic solid INTERACTION
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Anti-plane analysis of semi-infinite crack in piezoelectric strip 被引量:5
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作者 郭俊宏 刘萍 +1 位作者 卢子兴 秦太验 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第1期75-82,共8页
Using the complex variable function method and the technique of the conformal mapping, the fracture problem of a semi-infinite crack in a piezoelectric strip is studied under the anti-plane shear stress and the in-pla... Using the complex variable function method and the technique of the conformal mapping, the fracture problem of a semi-infinite crack in a piezoelectric strip is studied under the anti-plane shear stress and the in-plane electric load. The analytic solutions of the field intensity factors and the mechanical strain energy release rate are presented under the assumption that the surface of the crack is electrically impermeable. When the height of the strip tends to infinity, the analytic solutions of an infinitely large piezoelectric solid with a semi-infinite crack are obtained. Moreover, the present results can be reduced to the well-known solutions for a purely elastic material in the absence of the electric loading. In addition, numerical examples are given to show the influences of the loaded crack length, the height of the strip, and the applied mechanical/electric loads on the mechanical strain energy release rate. 展开更多
关键词 piezoelectric strip semi-infinite crack complex variable function method field intensity factor mechanical strain energy release rate
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Investigation on the penetration of jacketed rods with striking velocities of 0.9-3.3 km/s into semi-infinite targets 被引量:4
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作者 Kui Tang Jin-xiang Wang +1 位作者 Hai-ping Song Nan Zhou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第3期476-489,共14页
In this study, a combined experimental, numerical and theoretical investigation is conducted on the penetration of semi-infinite 4340 steel targets by a homogeneous 93 W rod and two types of jacketed rods with strikin... In this study, a combined experimental, numerical and theoretical investigation is conducted on the penetration of semi-infinite 4340 steel targets by a homogeneous 93 W rod and two types of jacketed rods with striking velocities of 0.9-3.3 km/s. The results show that the jacketed rods produced typical“co-erosion” damage at all test velocities, except for the 93 W/1060 Al jacketed rod, which switched from an early “bi-erosion” damage to later “co-erosion” damage at a striking velocity of 936 m/s. However, the homogeneous 93 W rod always forms a large mushroom head during the penetration process. The damage mechanisms of these two types of jacketed rods differ for striking velocities of 0.9-2.0 km/s, but this difference gradually decreases with increased striking velocity. For velocities of 2.0-3.3 km/s, all three types of projectiles exhibit typical hydrodynamic penetration characteristics, and the damage mechanisms of the two types of jacketed rods are almost identical. For the same initial kinetic energy, the penetration performance of the jacketed rods is distinctly superior to that of the homogeneous 93 W rods.Compared with jacket density, jacket strength shows a more significant influence on the damage mechanism and penetration performance of the jacketed rod. Finally, an existing theoretical prediction model of the penetration depth of jacketed rods on semi-infinite targets in the co-erosion mode is modified. It transpires that-in terms of penetration depth-the modified theoretical model is in good agreement with the experimental and numerical observations for 93 W/TC4 and 93 W/1060 Al jacketed rods penetrating semi-infinite 4340 steel targets. 展开更多
关键词 Jacketed rod semi-infinite target Damage mechanism Penetration performance
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Exact solutions of two semi-infinite collinear cracks in piezoelectric strip 被引量:3
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作者 卢子兴 刘萍 郭俊宏 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第11期1399-1406,共8页
Using the complex variable function method and the conformal mapping technique, the fracture problem of two semi-infinite collinear cracks in a piezoelectric strip is studied under the anti-plane shear stress and the ... Using the complex variable function method and the conformal mapping technique, the fracture problem of two semi-infinite collinear cracks in a piezoelectric strip is studied under the anti-plane shear stress and the in-plane electric load on the partial crack surface. Analytic solutions of the field intensity factors and the mechanical strain energy release rate are derived under the assumption that the surfaces of the crack are electrically impermeable. The results can be reduced to the well-known solutions for a purely elastic material in the absence of an electric load. Moreover, when the distance between the two crack tips tends to infinity, analytic solutions of a semi-infinite crack in a piezoelectric strip can be obtained. Numerical examples are given to show the influence of the loaded crack length, the height of the strip, the distance between the two crack tips, and the applied mechanical/electric loads on the mechanical strain energy release rate. It is shown that the material is easier to fail when the distance between two crack tips becomes shorter, and the mechanical/electric loads have greater influence on the propagation of the left crack than those of the right one. 展开更多
关键词 piezoelectric strip semi-infinite collinear crack complex variable function method field intensity factor mechanical strain energy release rate
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ASYMPTOTIC APPROXIMATION METHOD AND ITS CONVERGENCE ON SEMI-INFINITE PROGRAMMING 被引量:3
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作者 万仲平 王先甲 +1 位作者 何炬林 贾世会 《Acta Mathematica Scientia》 SCIE CSCD 2006年第1期17-24,共8页
The aim of this article is to discuss an asymptotic approximation model and its convergence for the minimax semi-infinite programming problem. An asymptotic surrogate constraints method for the minimax semi-infinite p... The aim of this article is to discuss an asymptotic approximation model and its convergence for the minimax semi-infinite programming problem. An asymptotic surrogate constraints method for the minimax semi-infinite programming problem is presented by making use of two general discrete approximation methods. Simultaneously, the consistence and the epi-convergence of the asymptotic approximation problem are discussed. 展开更多
关键词 semi-infinite programming asymptotic approximation CONVERGENCE
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Analytical models for the penetration of semi-infinite targets by rigid,deformable and erosive long rods 被引量:15
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作者 He-Ming Wen Bin Lan 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第4期573-583,共11页
A theoretical study is presented herein on the pen- etration of a semi-infinite target by a spherical-headed long rod for Yp 〉 S, where Yp is the penetrator strength and S is the static target resistance. For Yp 〉 S... A theoretical study is presented herein on the pen- etration of a semi-infinite target by a spherical-headed long rod for Yp 〉 S, where Yp is the penetrator strength and S is the static target resistance. For Yp 〉 S, depending upon initial impact velocity, there exist three types of penetration, namely, penetration by a rigid long rod, penetration by a deforming non-erosive long rod and penetration by an erosive long rod. If the impact velocity of the penetrator is higher than the hydrodynamic velocity (VH), it will penetrate the target in an erosive mode; if the impact velocity lies between the hydrodynamic velocity (VH) and the rigid body velocity (VR), it will penetrate the target in a deformable mode; if the impact velocity is less than the rigid body velocity (VR), it will penetrate the target in a rigid mode. The critical conditions for the transition among these three penetration modes are proposed. It is demonstrated that the present model predictions correlate well with the experimental observations in terms of depth of penetration (DOP) and the critical transition conditions. 展开更多
关键词 Long rod semi-infinite target - Penetration Alekseevskii-Tate model Rigid body velocity - Hydrodynamic velocity
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Interaction between infinitely many dislocations and a semi-infinite crack in one-dimensional hexagonal quasicrystal 被引量:10
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作者 刘官厅 杨丽英 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期280-284,共5页
By means of analytic function theory, the problems of interaction between infinitely many parallel dislocations and a semi-infinite crack in one-dimensional hexagonal quasicrystal are studied. The analytic solutions o... By means of analytic function theory, the problems of interaction between infinitely many parallel dislocations and a semi-infinite crack in one-dimensional hexagonal quasicrystal are studied. The analytic solutions of stress fields of the interaction between infinitely many parallel dislocations and a semi-infinite crack in one-dimensional hexagonal quasicrystal are obtained. They indicate that the stress concentration occurs at the dislocation source and the tip of the crack, and the value of the stress increases with the number of the dislocations increasing. These results are the development of interaction among the finitely many defects of quasicrystals, which possesses an important reference value for studying the interaction problems of infinitely many defects in fracture mechanics of quasicrystal. 展开更多
关键词 quasicrystals infinitely many dislocations semi-infinite crack interaction
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A Problem of a Semi-Infinite Medium Subjected to Exponential Heating Using a Dual-Phase-Lag Thermoelastic Model 被引量:2
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作者 Ahmed E. Abouelregal 《Applied Mathematics》 2011年第5期619-624,共6页
The problem of a semi-infinite medium subjected to thermal shock on its plane boundary is solved in the context of the dual-phase-lag thermoelastic model. The expressions for temperature, displacement and stress are p... The problem of a semi-infinite medium subjected to thermal shock on its plane boundary is solved in the context of the dual-phase-lag thermoelastic model. The expressions for temperature, displacement and stress are presented. The governing equations are expressed in Laplace transform domain and solved in that domain. The solution of the problem in the physical domain is obtained by using a numerical method for the inversion of the Laplace transforms based on Fourier series expansions. The numerical estimates of the displacement, temperature, stress and strain are obtained for a hypothetical material. The results obtained are presented graphically to show the effect phase-lag of the heat flux and a phase-lag of temperature gradient on displacement, temperature, stress. 展开更多
关键词 Generalized THERMOELASTICITY Dual-Phase-Lag Model semi-infinite MEDIUM LAPLACE Transform
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Necessary Optimality Conditions for Multi-Objective Semi-Infinite Variational Problem 被引量:1
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作者 Bharti Sharma Promila Kumar 《American Journal of Operations Research》 2016年第1期36-43,共8页
In this paper, necessary optimality conditions for a class of Semi-infinite Variational Problems are established which are further generalized to a class of Multi-objective Semi-Infinite Variational Problems. These co... In this paper, necessary optimality conditions for a class of Semi-infinite Variational Problems are established which are further generalized to a class of Multi-objective Semi-Infinite Variational Problems. These conditions are responsible for the development of duality theory which is an extremely important feature for any class of problems, but the literature available so far lacks these necessary optimality conditions for the stated problem. A lemma is also proved to find the topological dual of  as it is required to prove the desired result. 展开更多
关键词 semi-infinite Variational Problem Efficient Solution Necessary Optimality Conditions
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Consideration of transient heat conduction in a semi-infinite medium using homotopy analysis method
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作者 A. Rezania A. Ghorbali +1 位作者 G. Domairry H. Bararnia 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第12期1625-1632,共8页
In the current work, transient heat conduction in a semi-infinite medium is considered for its many applications in various heat fields. Here, the homotopy analysis method (HAM) is applied to solve this problem and ... In the current work, transient heat conduction in a semi-infinite medium is considered for its many applications in various heat fields. Here, the homotopy analysis method (HAM) is applied to solve this problem and analytical results are compared with those of the exact and integral methods results. The results show that the HAM can give much better approximations than the other approximate methods: Changes in heat fluxes and profiles of temperature are obtained at different times and positions for copper, iron and aluminum. 展开更多
关键词 homotopy analysis method semi-infinite medium conduction transient heat transfer integral methods temperature profile
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Green's function for T-stress of semi-infinite plane crack
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作者 崔元庆 杨卫 仲政 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第8期973-980,共8页
Green’s function for the T-stress near a crack tip is addressed with an analytic function method for a semi-infinite crack lying in an elastical, isotropic, and infinite plate. The cracked plate is loaded by a single... Green’s function for the T-stress near a crack tip is addressed with an analytic function method for a semi-infinite crack lying in an elastical, isotropic, and infinite plate. The cracked plate is loaded by a single inclined concentrated force at an interior point. The complex potentials are obtained based on a superposition principle, which provide the solutions to the plane problems of elasticity. The regular parts of the potentials are extracted in an asymptotic analysis. Based on the regular parts, Green’s function for the T-stress is obtained in a straightforward manner. Furthermore, Green’s functions are derived for a pair of symmetrically and anti-symmetrically concentrated forces by the superimposing method. Then, Green’s function is used to predict the domain-switch-induced T-stress in a ferroelectric double cantilever beam (DCB) test. The T-stress induced by the electromechanical loading is used to judge the stable and unstable crack growth behaviors observed in the test. The prediction results generally agree with the experimental data. 展开更多
关键词 Green’s function T-STRESS complex variable function semi-infinite crack fracture mechanics
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Quantum diffusion in semi-infinite periodic and quasiperiodic systems
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作者 张凯旺 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期1113-1118,共6页
This paper studies quantum diffusion in semi-infinite one-dimensional periodic lattice and quasiperiodic Fibonacci lattice. It finds that the quantum diffusion in the semi-infinite periodic lattice shows the same prop... This paper studies quantum diffusion in semi-infinite one-dimensional periodic lattice and quasiperiodic Fibonacci lattice. It finds that the quantum diffusion in the semi-infinite periodic lattice shows the same properties as that for the infinite periodic lattice. Different behaviour is found for the semi-infinite Fibonacci lattice. In this case, there are still C(t) - t^-δ and d(t) - t^β. However, it finds that 0 〈δ 〈 1 for smaller time, and δ = 0 for larger time due to the influence of surface localized states. Moreover, β for the semi-infinite Fibonacci lattice is much smaller than that for the infinite Fibonacci lattice. Effects of disorder on the quantum diffusion are also discussed. 展开更多
关键词 quantum diffusion semi-infinite periodic lattice quasiperiodic Fibonacci lattice
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FINITE LAYER ANALYSIS FOR SEMI-INFINITE SOILS (Ⅰ)——GENERAL THEORY
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作者 杨正文 卢文达 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第10期917-927,共11页
In the present paper a finite layer method is studied for the flastodynarnics of transverse isotropic bodies. With this method, semi-infinite soils can be considered as an transverse isotropic half-space, its material... In the present paper a finite layer method is studied for the flastodynarnics of transverse isotropic bodies. With this method, semi-infinite soils can be considered as an transverse isotropic half-space, its material functions varying with depth. Dividing the half-space into a scries of layers in the direction of depth, the material junctions in each layer are simulated by exponential functions Consequently, the fundamental equations to be solved can be simplified if the Fourier transform with repsect to coordinates is used. We have obtained the relationship between the 'layer forces' and 'layer displacements'. This finite layer method, in fact, can also be called a semi-analytical method. It possesses those advantages as the usual semi-analytical methods do, and can be used to analyse the problem of the interaction between soils and structures. 展开更多
关键词 finite layer method transverse isotropy semi-infinite region ELASTODYNAMICS
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Deriving Vibration Modes of Semi-infinite Chain Model by “Invariant Eigen-operator”Method
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作者 FAN Hong-Yi WU Hao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第1期50-52,共3页
For the first time, we introduce a fully quantum mechanical Hamiltonian for a semi-infinite chain model of atoms. We then derive the vibration modes of this model by virtue of the "invariant eigen-operator" method i... For the first time, we introduce a fully quantum mechanical Hamiltonian for a semi-infinite chain model of atoms. We then derive the vibration modes of this model by virtue of the "invariant eigen-operator" method in two different cases, which is concise and revealing. 展开更多
关键词 semi-infinite chain vibration modes IEO method
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Three-Dimensional Thermal-Stress Analysis of Semi-infinite Transversely Isotropic Composites
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作者 TOKOVYY Yuriy BOIKO Dmytro GAO Cunfa 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第1期18-28,共11页
By making use of the direct integration method,an exact analysis of the general three-dimensional thermoelasticity problem is performed for the case of a transversely isotropic homogeneous half-space subject to local ... By making use of the direct integration method,an exact analysis of the general three-dimensional thermoelasticity problem is performed for the case of a transversely isotropic homogeneous half-space subject to local thermal and force loadings.The material plane of isotropy is assumed to be parallel to the limiting surface of the halfspace.By reducing the original thermoelasticity equations to the governing ones for individual stress-tensor components,the effect of material anisotropy in the stress field is analyzed with regard to the feasibility requirement,i.e.,the finiteness of the stress field at a distance from the disturbed area.As a result,the solution is constructed in the form of explicit analytical dependencies on the force and thermal loadings for various kinds of transversely isotropic materials and agrees with the basic principles of the continua mechanics.The solution can be efficiently used as a benchmark one for the direct computation of temperature and thermal stresses in transversely isotropic semi-infinite domains,as well as for the verification of solutions constructed by different means. 展开更多
关键词 three-dimensional problem analytical solution transversely isotropic composites semi-infinite model force and thermal loadings finite stress distributions
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Analytical solutions of steady vibration of free rectangular plate on semi-infinite elastic foundation
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作者 王春玲 黄义 贾继红 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第2期173-182,共10页
The method of double Fourier transform Was employed in the analysis of the semi-infinite elastic foundation with vertical load. And an integral representations for the displacements of the semi-infinite elastic founda... The method of double Fourier transform Was employed in the analysis of the semi-infinite elastic foundation with vertical load. And an integral representations for the displacements of the semi-infinite elastic foundation was presented. The analytical solution of steady vibration of an elastic rectangle plate with four free edges on the semi-infinite elastic foundation was also given by combining the analytical solution of the elastic rectangle plate with the integral representation for displacements of the semiinfinite elastic foundation. Some computational results and the analysis on the influence of parameters were presented. 展开更多
关键词 semi-infinite elastic foundation rectangular plate with four free edges steady vibration INTERACTION analytical solution
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FINITE LAYER ANALYSIS FOR SEMI-INFINITE SOILS (Ⅱ)——SPECIAL CASES AND NUMERICAL EXAMPLES
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作者 卢文达 杨正文 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第11期987-993,共7页
In the present paper reductions of the finite layer mathod once studied in detail by the authors for the elastodvnamics of transverse isotropic bodies are given to several special cases. Two-dimensional problems, axis... In the present paper reductions of the finite layer mathod once studied in detail by the authors for the elastodvnamics of transverse isotropic bodies are given to several special cases. Two-dimensional problems, axisymmetric problems and static problems are discussed, respectively, and this finite layer method is also generalized to the problems in which materials possess viscous properties. Two numerical examples have been presented for the axisymmetric case. From these two examples it can be concluded that the finite layer method can be used to analyse semi-infinite layered soils and to deal with the problem of the interaction between soils and structures. 展开更多
关键词 semi-infinite soils finite layer method numerical analysis
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ELASTOSTATIC SOLUTOINS FOR SEMI-INFINITE ORTHOTROPIC CANTILEVERED STRIPS
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作者 Li Yi-han 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第11期1063-1070,共8页
The elastostatic solutions of semi-infinite orthotropic cantilevered strips with traction free edges and loading at infinity are governed by the differential equationφ,■+(2+δ_(0))φ,■+φ,■=0 withδ_(0)>-4 with... The elastostatic solutions of semi-infinite orthotropic cantilevered strips with traction free edges and loading at infinity are governed by the differential equationφ,■+(2+δ_(0))φ,■+φ,■=0 withδ_(0)>-4 with Based on the work of[10]forδ_(0)>0 case,.this paper completes the caseδ_(0)=0 for isotropic materials and the case 0>δ_(0)>-4 for orthotropic materials.The solutions of the above problems have important application in the properly formulated boundary conditions of plate theories for prescribed displacement edge data. 展开更多
关键词 semi-infinite orthotropic strip stress singularity at clamped end generalized Cauchy type singular integral equation
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The Optimality Conditions for Multiobjective Semi-infinite Programming Involving Generalized Unified (C, α, p, d)-convexity
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作者 ZHANG Qing-xiang ZHANG Yong-zhan 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第2期241-249,共9页
The definition of generalized unified (C, α, ρ, d)-convex function is given. The concepts of generalized unified (C, α, ρ, d)-quasiconvexity, generalized unified (C, α, ρ, d)-pseudoconvexity and generalized unif... The definition of generalized unified (C, α, ρ, d)-convex function is given. The concepts of generalized unified (C, α, ρ, d)-quasiconvexity, generalized unified (C, α, ρ, d)-pseudoconvexity and generalized unified (C, α, ρ, d)-strictly pseudoconvex functions are presented. The sufficient optimality conditions for multiobjective nonsmooth semi-infinite programming are obtained involving these generalized convexity lastly. 展开更多
关键词 generalized convexity multiobjective semi-infinite programming efficient solution optimality conditions
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