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Conditional Generative Adversarial Network Enabled Localized Stress Recovery of Periodic Composites
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作者 Chengkan Xu Xiaofei Wang +2 位作者 Yixuan Li Guannan Wang He Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期957-974,共18页
Structural damage in heterogeneousmaterials typically originates frommicrostructures where stress concentration occurs.Therefore,evaluating the magnitude and location of localized stress distributions within microstru... Structural damage in heterogeneousmaterials typically originates frommicrostructures where stress concentration occurs.Therefore,evaluating the magnitude and location of localized stress distributions within microstructures under external loading is crucial.Repeating unit cells(RUCs)are commonly used to represent microstructural details and homogenize the effective response of composites.This work develops a machine learning-based micromechanics tool to accurately predict the stress distributions of extracted RUCs.The locally exact homogenization theory efficiently generates the microstructural stresses of RUCs with a wide range of parameters,including volume fraction,fiber/matrix property ratio,fiber shapes,and loading direction.Subsequently,the conditional generative adversarial network(cGAN)is employed and constructed as a surrogate model to establish the statistical correlation between these parameters and the corresponding localized stresses.The stresses predicted by cGAN are validated against the remaining true data not used for training,showing good agreement.This work demonstrates that the cGAN-based micromechanics tool effectively captures the local responses of composite RUCs.It can be used for predicting potential crack initiations starting from microstructures and evaluating the effective behavior of periodic composites. 展开更多
关键词 Periodic composites localized stress recovery conditional generative adversarial network
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Optimization of Generator Based on Gaussian Process Regression Model with Conditional Likelihood Lower Bound Search
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作者 Xiao Liu Pingting Lin +2 位作者 Fan Bu Shaoling Zhuang Shoudao Huang 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期32-42,共11页
The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regressi... The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regression(GPR)model based on Conditional Likelihood Lower Bound Search(CLLBS)to optimize the design of the generator,which can filter the noise in the data and search for global optimization by combining the Conditional Likelihood Lower Bound Search method.Taking the efficiency optimization of 15 kW Permanent Magnet Synchronous Motor as an example.Firstly,this method uses the elementary effect analysis to choose the sensitive variables,combining the evolutionary algorithm to design the super Latin cube sampling plan;Then the generator-converter system is simulated by establishing a co-simulation platform to obtain data.A Gaussian process regression model combing the method of the conditional likelihood lower bound search is established,which combined the chi-square test to optimize the accuracy of the model globally.Secondly,after the model reaches the accuracy,the Pareto frontier is obtained through the NSGA-II algorithm by considering the maximum output torque as a constraint.Last,the constrained optimization is transformed into an unconstrained optimizing problem by introducing maximum constrained improvement expectation(CEI)optimization method based on the re-interpolation model,which cross-validated the optimization results of the Gaussian process regression model.The above method increase the efficiency of generator by 0.76%and 0.5%respectively;And this method can be used for rapid modeling and multi-objective optimization of generator systems. 展开更多
关键词 generator optimization Gaussian Process Regression(GPR) conditional Likelihood Lower Bound Search(CLLBS) Constraint improvement expectation(CEI) Finite element calculation
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Necessary and Sufficient Conditions in Smooth Programming with Generalized Convexity 被引量:1
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作者 孙清滢 叶留青 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第4期33-37,共5页
Hanson and Mond have grven sets of necessary and sufficient conditions for optimality in constrained optimization by introducing classes of generalized functions, called type Ⅰ functions. Recently, Bector definded un... Hanson and Mond have grven sets of necessary and sufficient conditions for optimality in constrained optimization by introducing classes of generalized functions, called type Ⅰ functions. Recently, Bector definded univex functions, a new class of functions that unifies several concepts of generalized convexity. In this paper, additional conditions are attached to the Kuhn Tucker conditions giving a set of conditions which are both necessary and sufficient for optimality in constrained optimization, under appropriate constraint qualifications. 展开更多
关键词 necessary and sufficient conditions generalized convexity nonlinear programming multiobjective programming type functions
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Criteria Condition for Generalized Diagonally Dominant Matrices 被引量:3
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作者 田素霞 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第1期102-106,共5页
In this paper, we provide some new necessary and sufficient conditions for generalized diagonally dominant matrices and also obtain some criteria for nongeneralized dominant matrices.
关键词 generalized diagonally dominant matrices Positive diagonal matrix criteria condition
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Dynamic stiffness method for free vibration of an axially moving beam with generalized boundary conditions 被引量:3
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作者 Hu DING Minhui ZHU Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第7期911-924,共14页
Axially moving beams are often discussed with several classic boundary conditions, such as simply-supported ends, fixed ends, and free ends. Here, axially moving beams with generalized boundary conditions are discusse... Axially moving beams are often discussed with several classic boundary conditions, such as simply-supported ends, fixed ends, and free ends. Here, axially moving beams with generalized boundary conditions are discussed for the first time. The beam is supported by torsional springs and vertical springs at both ends. By modifying the stiffness of the springs, generalized boundaries can replace those classical boundaries. Dynamic stiffness matrices are, respectively, established for axially moving Timoshenko beams and Euler-Bernoulli (EB) beams with generalized boundaries. In order to verify the applicability of the EB model, the natural frequencies of the axially moving Timoshenko beam and EB beam are compared. Furthermore, the effects of constrained spring stiffness on the vibration frequencies of the axially moving beam are studied. Interestingly, it can be found that the critical speed of the axially moving beam does not change with the vertical spring stiffness. In addition, both the moving speed and elastic boundaries make the Timoshenko beam theory more needed. The validity of the dynamic stiffness method is demonstrated by using numerical simulation. 展开更多
关键词 AXIALLY moving BEAM natural frequency TIMOSHENKO BEAM model DYNAMIC stiffness matrix generalized boundary condition
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Generalized Demodulation Transform for Bearing Fault Diagnosis Under Nonstationary Conditions and Gear Noise Interferences 被引量:2
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作者 Dezun Zhao Jianyong Li +1 位作者 Weidong Cheng Zhiyang He 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第1期79-89,共11页
It is a challenging issue to detect bearing fault under nonstationary conditions and gear noise interferences. Meanwhile, the application of the traditional methods is limited by their deficiencies in the aspect of co... It is a challenging issue to detect bearing fault under nonstationary conditions and gear noise interferences. Meanwhile, the application of the traditional methods is limited by their deficiencies in the aspect of computational accuracy and e ciency, or dependence on the tachometer. Hence, a new fault diagnosis strategy is proposed to remove gear interferences and spectrum smearing phenomenon without the tachometer and angular resampling technique. In this method, the instantaneous dominant meshing multiple(IDMM) is firstly extracted from the time-frequency representation(TFR) of the raw signal, which can be used to calculate the phase functions(PF) and the frequency points(FP). Next, the resonance frequency band excited by the faulty bearing is obtained by the band-pass filter. Furthermore, based on the PFs, the generalized demodulation transform(GDT) is applied to the envelope of the filtered signal. Finally, the target bearing is diagnosed by matching the peaks in the spectra of demodulated signals with the theoretical FPs. The analysis results of simulated and experimental signal demonstrate that the proposed method is an e ective and reliable tool for bearing fault diagnosis without the tachometer and the angular resampling. 展开更多
关键词 Bearing fault diagnosis generalized DEMODULATION TRANSFORM NONSTATIONARY conditionS Gear noise
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Generalized δ-entropy condition to Riemann solution for Chaplygin gas in traffic flow 被引量:1
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作者 Wancheng SHENG Ying ZENG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第3期353-364,共12页
The Riemann problem for the Aw-Rascle model in the traffic flow with the Delta initial data for the Chaplygin gas is studied. The solutions are constructed globally under the generalized Rankine-Hugoniot relations, t... The Riemann problem for the Aw-Rascle model in the traffic flow with the Delta initial data for the Chaplygin gas is studied. The solutions are constructed globally under the generalized Rankine-Hugoniot relations, the δ-entropy conditions, and the generalized δ-entropy conditions. A new Delta wave, which is called a primary Delta wave, is defined in some solutions. The primary Delta wave satisfies the generalized Rankine- Hugoniot relations and the generalized δ-entropy conditions. It generates initially from the Delta initial data, which either evaluates a Delta wave, whose weight becomes stronger and stronger, or disappears at a finite time. 展开更多
关键词 generalized δ-entropy condition Riemann problem for Aw-Rascle model generalized rankine-hugoniot relation Delta initial datum Chaplygin gas
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Optimality conditions and duality for a class of nondifferentiable multiobjective generalized fractional programming problems 被引量:1
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作者 GAO Ying RONG Wei-dong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第3期331-344,共14页
This paper studies a class of multiobjective generalized fractional programming problems, where the numerators of objective functions are the sum of differentiable function and convex function, while the denominators ... This paper studies a class of multiobjective generalized fractional programming problems, where the numerators of objective functions are the sum of differentiable function and convex function, while the denominators are the difference of differentiable function and convex function. Under the assumption of Calmness Constraint Qualification the Kuhn-Tucker type necessary conditions for efficient solution are given, and the Kuhn-Tucker type sufficient conditions for efficient solution are presented under the assumptions of (F, α, ρ, d)-V-convexity. Subsequently, the optimality conditions for two kinds of duality models are formulated and duality theorems are proved. 展开更多
关键词 operations research multiobjective generalized fractional programming optimality condition duality theorem generalized convexity
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Approximate Generalized Conditional Symmetries for Perturbed Evolution Equations 被引量:3
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作者 ZHANG Shun-Li WANG Yong LOU Sen-Yue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第6期975-980,共6页
The concept of approximate generalized conditional symmetry (AGCS) for the perturbed evolution equations is introduced, and how to derive approximate conditional invariant solutions to the perturbed equations via th... The concept of approximate generalized conditional symmetry (AGCS) for the perturbed evolution equations is introduced, and how to derive approximate conditional invariant solutions to the perturbed equations via their A GCSs is illustrated with examples. 展开更多
关键词 perturbed evolution equation approximate generalized conditional symmetry approximate con ditional invariant solution
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Criteria Conditions for Generalized Diagonally Dominant Matrices 被引量:3
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作者 TIAN Su-xia 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期63-67,共5页
In this paper, some new sufficient conditions for generalized dominant matrices are given, and some results in [1] are generalized and improved.
关键词 generalized diagonal dominant matrices α-diagonal dominant matrix criteria condition
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Multivariate Generalized Autoregressive Conditional Heteroscedastic Model 被引量:1
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作者 史宁中 刘继春 《Northeastern Mathematical Journal》 CSCD 2001年第3期323-332,共10页
In this paper, by making use of the Hadamard product of matrices, a natural and reasonable generalization of the univariate GARCH (Generalized Autoregressive Conditional heteroscedastic) process introduced by Bollersl... In this paper, by making use of the Hadamard product of matrices, a natural and reasonable generalization of the univariate GARCH (Generalized Autoregressive Conditional heteroscedastic) process introduced by Bollerslev (J. Econometrics 31(1986), 307-327) to the multivariate case is proposed. The conditions for the existence of strictly stationary and ergodic solutions and the existence of higher-order moments for this class of parametric models are derived. 展开更多
关键词 generalized autoregressive conditional heteroscedastic model strict stationarity Hadamard product
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A PRIORI ESTIMATES TO THE MAXIMUM MODULUS OF GENERALIZED SOLUTIONS OF A CLASS OF QUASILINEAR ELLIPTIC EQUATIONS WITH ANISOTROPIC GROWTH CONDITIONS 被引量:1
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作者 梁廷 王向东 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第11期1025-1034,共10页
In this paper we give a priori estimates for the maximum modulus of generalizedsolulions of the quasilinear elliplic equations irith anisotropic growth condition.
关键词 quasilinear elliptic equation. nonstandard growth condition.anisotropic Sobolev space. generalized solution. maximum mod-ulus. a priori estimate
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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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Consistency Conditions and Constraints on Generalized f(R) Gravity with Arbitrary Geometry-Matter Coupling
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作者 吴思雨 吴亚波 +3 位作者 赵月月 张雪 张成园 陈博海 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第3期146-149,共4页
We study the consistency conditions of the generalized f ( R) gravity by extending f ( R) gravity with non-minimal coupling to the generalized f(R) with arbitrary geometry-matter coupling. Specifically, we discu... We study the consistency conditions of the generalized f ( R) gravity by extending f ( R) gravity with non-minimal coupling to the generalized f(R) with arbitrary geometry-matter coupling. Specifically, we discuss the two particular models of generalized f(R) by means of consistency conditions. It is found that the second model is not physically viable so as to be ruled out. Moreover, we further constrain the first model using the Dolgov- Kawasaki stability criterion, and give the value ranges of the parameters in the first model It is worth stressing that our results include the ones in f(R) gravity with non-minimal coupling as the special case of Q(Lm) = Lm. 展开更多
关键词 on is it of in Consistency conditions and Constraints on generalized f Gravity with Arbitrary Geometry-Matter Coupling been with
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COMPONENTWISE CONDITION NUMBERS FOR GENERALIZED MATRIX INVERSION AND LINEAR LEAST SQUARES 被引量:1
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作者 魏益民 许威 +1 位作者 乔三正 刁怀安 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2005年第3期277-286,共10页
We present componentwise condition numbers for the problems of MoorePenrose generalized matrix inversion and linear least squares. Also, the condition numbers for these condition numbers are given.
关键词 矩阵倒置 线性最小正方形 广义性 灵敏度
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Criteria Conditions for Generalized Diagonally Dominant Matrices
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作者 TIAN Su-xia 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期397-402,共6页
In this paper, we provide some new criteria conditions for generalized strictly diagonally dominant matrices, such that the corresponding results in [1] are generalized and improved.
关键词 generalized diagonal dominant matrices a-diagonal dominant matrix criteria condition
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Application of generalized impedance boundary conditions to sommerfeld half-space problem
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作者 江滨浩 刘永坦 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第2期179-183,共5页
Generalized impedance boundary conditions are employed to simplify the solution of the Sommerfeld half-space problem. An analytical expression is derived for the Hertz potential of a vertical electric dipole over the ... Generalized impedance boundary conditions are employed to simplify the solution of the Sommerfeld half-space problem. An analytical expression is derived for the Hertz potential of a vertical electric dipole over the earth’s surface, in which the earth is assumed to be a layered media or homogeneous dissipative half-space. A Sommerfeld type integral in the potential function is expressed as the sum of two parts: a zeroth order Hankel function and an absolutely convergent series of Bessel functions. In addition, two expressions in closed form are obtained as the far-field and near-field approximation of the present result. 展开更多
关键词 electromagnetic theory sommerfeld type integral generalized impedance boundary conditions analytical expression
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Direct and Reverse Carleson Conditions on Generalized Weighted Bergman-Orlicz Spaces
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作者 Waleed Al-Rawashdeh 《Analysis in Theory and Applications》 CSCD 2017年第3期287-300,共14页
Let D be the open unit disk in the complex plane C. For a〉 -1, let dAa(z)=(1 +a) (1 -|z}^2) ^a da(z)be the weighted Lebesgue measure on ]D. For a positive function ω ∈ L^1(D,dAa), the generalized weight... Let D be the open unit disk in the complex plane C. For a〉 -1, let dAa(z)=(1 +a) (1 -|z}^2) ^a da(z)be the weighted Lebesgue measure on ]D. For a positive function ω ∈ L^1(D,dAa), the generalized weighted Bergman-Orlicz spaceA^ψω(D,dAa)is||f||ω^ψ=∫Dψ|F(z)|ω(z)dA^(z) 〈 ∞,where q; is a strictly convex Orlicz function that satisfies other technical hypotheses. Let G be a measurable subset of D, we say G satisfies the reverse Carleson condition for A^ψω (D, dAa) if there exists a positive constant C such that ∫Gψ(f(z))ω(z)dAa(z)≥C∫Dψ(|f(z)dAa(z).for all f ∈ .A^ψω (D,dAa). Let μ be a positive Borel measure, we say μ satisfies the direct Carleson condition if there exists a positive constant M such that for all f∈Aψ^ω (D,dAa),∫Dψ(|f(z)|)dμ(z)≤M∫Dψ(|f(z)|)ω(z)dAa(a).In this paper, we study the direct and reverse Carleson condition on the generalized weighted Bergman-Orlicz space Aω^ψ(D,dAa).We present conditions on the set G such that'the reverse Carleson condition'holds. "Moreover, we give a sufficient condition for the finite positive Borel measure μ to satisfy the direct carleson condition on the generalized weighted Bergman-Orlicz spaces. 展开更多
关键词 Orlicz function global ?2-condition reverse Carleson condition Direct Carleson condition closed range Pseudohyperbolic disks Orlicz spaces weighted Bergman spaces generalized weighted Bergman-Orlicz spaces
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Energy Conditions and Constraints on the Generalized Non-Local Gravity Model
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作者 吴亚波 张雪 +2 位作者 陈博海 张楠 武蒙蒙 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期287-291,共5页
We study and derive the energy conditions in generalized non-local gravity, which is the modified theory of general relativity obtained by adding a term m2n-2R□-nRto the Einstein-Hilbert action. Moreover, to obtain s... We study and derive the energy conditions in generalized non-local gravity, which is the modified theory of general relativity obtained by adding a term m2n-2R□-nRto the Einstein-Hilbert action. Moreover, to obtain some insight on the meaning of the energy conditions, we illustrate the evolutions of four energy conditions with the model parameter ε for different n. By analysis we give the constraints on the model parameters ε. 展开更多
关键词 Energy conditions and Constraints on the generalized Non-Local Gravity Model DEC
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SOLUTION TO A PARAMETRIC EQUATION WITH GENERALIZED BOUNDARY CONDITION IN TRANSPORT THEORY
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作者 王胜华 姚爱翔 《Acta Mathematica Scientia》 SCIE CSCD 1992年第4期435-442,共8页
This paper deals with the solution of a parametric equation with generalized boundary condiiton in transport theory. It gives the distribution of parameter (so called delta-eigenvalue [1]) with which the equation has ... This paper deals with the solution of a parametric equation with generalized boundary condiiton in transport theory. It gives the distribution of parameter (so called delta-eigenvalue [1]) with which the equation has non-zero solution. A necessary and sufficient condition for the existence of; he control critical eigenvalue delta0 is established. 展开更多
关键词 SOLUTION TO A PARAMETRIC EQUATION WITH generalized BOUNDARY condition IN TRANSPORT THEORY Za
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