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Structural eigenvalue analysis under the constraint of a fuzzy convex set model 被引量:1
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作者 Wencai Sun Zichun Yang Guobing Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2018年第4期653-666,共14页
In small-sample problems, determining and controlling the errors of ordinary rigid convex set models are difficult. Therefore, a new uncertainty model called the fuzzy convex set(FCS) model is built and investigated... In small-sample problems, determining and controlling the errors of ordinary rigid convex set models are difficult. Therefore, a new uncertainty model called the fuzzy convex set(FCS) model is built and investigated in detail. An approach was developed to analyze the fuzzy properties of the structural eigenvalues with FCS constraints. Through this method, the approximate possibility distribution of the structural eigenvalue can be obtained. Furthermore, based on the symmetric F-programming theory, the conditional maximum and minimum values for the structural eigenvalue are presented, which can serve as nonfuzzy quantitative indicators for fuzzy problems. A practical application is provided to demonstrate the practicability and effectiveness of the proposed methods. 展开更多
关键词 Structural eigenvalue FUZZY convex set Conditional extreme Symmetric F-programming
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Vertical derivative conversion of irregular-range potential fi eld data based on improved projection onto convex sets method 被引量:1
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作者 Zeng Xiao-Niu Li Xi-Hai +2 位作者 Yu Xiao-Tong Liu Ji-Hao Liu Dai-Zhi 《Applied Geophysics》 SCIE CSCD 2021年第4期461-472,592,共13页
Gravity and magnetic exploration areas are usually irregular,and there is some data defi ciency.Missing data must be interpolated before the vertical derivative conversion in the wavenumber domain.Meanwhile,for improv... Gravity and magnetic exploration areas are usually irregular,and there is some data defi ciency.Missing data must be interpolated before the vertical derivative conversion in the wavenumber domain.Meanwhile,for improved processing precision,the data need to be edge-padded to the length required by the fast Fourier transform algorithm.For conventional vertical derivative conversion of potential fi eld data(PFD),only vertical derivative conversion is considered,or interpolation,border padding,and vertical derivative conversion are executed independently.In this paper,these three steps are considered uniformly,and a vertical derivative conversion method for irregular-range PFD based on an improved projection onto convex sets method is proposed.The cutoff wavenumber of the filter used in the proposed method is determined by fractal model fi tting of the radial average power spectrum(RAPS)of the potential fi eld.Theoretical gravity models and real aeromagnetic data show the following:(1)The fitting of the RAPS with a fractal model can separate useful signals and noise reasonably.(2)The proposed iterative method has a clear physical sense,and its interpolation,border padding error,and running time are much smaller than those of the conventional kriging and minimum curvature methods. 展开更多
关键词 Potential fi eld vertical derivative projection onto convex sets fractal model
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Convex Set Theory for Reliability Assessment of Steel Beam with Bounded Uncertainty
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作者 Li-Zhe Jia Yi-Ming Duan 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第2期91-96,共6页
Probabilistic reliability model established by insufficient data is inaccessible. The convex model was applied to model the uncertainties of variables. A new non-probabilistic reliability model was proposed based on t... Probabilistic reliability model established by insufficient data is inaccessible. The convex model was applied to model the uncertainties of variables. A new non-probabilistic reliability model was proposed based on the robustness of system to uncertainty. The non-probabilistic reliability model,the infinite norm model,and the probabilistic model were used to assess the reliability of a steel beam,respectively. The results show that the resistance is allowed to couple with the action effect in the non-probabilistic reliability model. Additionally,the non-probabilistic reliability model becomes the same accurate as probabilistic model with the increase of the bounded uncertain information. The model is decided by the available data and information. 展开更多
关键词 non-probabilistic model convex set theory structural reliability
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Optimal Separation of Twin Convex Sets under Externalities
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作者 Indrajit Mallick 《Advances in Pure Mathematics》 2014年第8期381-390,共10页
This paper studies the outcomes of independent and interdependent pair-wise contests between economic agents subject to an optimal external decision problem for each pair. The external decision maker like the governme... This paper studies the outcomes of independent and interdependent pair-wise contests between economic agents subject to an optimal external decision problem for each pair. The external decision maker like the government or regulator is faced with the problem of how to devise rules and regulations regarding contests. In this paper, a decision problem is faced under negative and positive externalities. A pair of entities is represented by disjoint convex sets in a small area in a neighborhood. I assume that each entity imposes an equal externality on the other (and the other only) and thus they can be considered to be twins. Among the group of twins in any neighborhood, there is a set of twin pairs such that, for each pair in the set, each twin can impose a strictly negative externality on the other (and the other only), and this is a potential welfare loss which concerns the decision maker. A separating hyper-plane can block the negative externalities between any pair of twins given convexity. However, this can be costly if positive externality from the neighborhood is also blocked by the separation technology. Thus, this paper compares the pair-wise utility from separation to that of non-separation. A simple representation of the decision problem is developed with respect to a single and isolated neighborhood. A complete characterization of the decision problem is obtained with a large number of pair-wise intersecting neighborhoods. 展开更多
关键词 convex set SEPARATION EXTERNALITY
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Martingales and Super-Martingales Relative to a Convex Set of Equivalent Measures
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作者 Nicholas S. Gonchar 《Advances in Pure Mathematics》 2018年第4期428-462,共35页
In the paper, the martingales and super-martingales relative to a convex set of equivalent measures are systematically studied. The notion of local regular super-martingale relative to a convex set of equivalent measu... In the paper, the martingales and super-martingales relative to a convex set of equivalent measures are systematically studied. The notion of local regular super-martingale relative to a convex set of equivalent measures is introduced and the necessary and sufficient conditions of the local regularity of it in the discrete case are founded. The description of all local regular super-martingales relative to a convex set of equivalent measures is presented. The notion of the complete set of equivalent measures is introduced. We prove that every bounded in some sense super-martingale relative to the complete set of equivalent measures is local regular. A new definition of the fair price of contingent claim in an incomplete market is given and the formula for the fair price of Standard Option of European type is found. The proved Theorems are the generalization of the famous Doob decomposition for super-martingale onto the case of super-martingales relative to a convex set of equivalent measures. 展开更多
关键词 Random Process convex set of EQUIVALENT Measures Optional Doob Decomposition Local Regular Super-Martingale MARTINGALE Fair Price of CONTINGENT CLAIM
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On Drop and Weak Drop Properties for Bounded Closed Convex Sets*
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作者 张子厚 《Journal of Mathematical Research and Exposition》 CSCD 1999年第4期667-672,共6页
In this paper we prove three equivalent conditions of bounded closed convexset K in Banach space to have the drop and weak drop properties. We also give fourequivalent conditions of Banach space and its dual space to ... In this paper we prove three equivalent conditions of bounded closed convexset K in Banach space to have the drop and weak drop properties. We also give fourequivalent conditions of Banach space and its dual space to have the drop and weak dropproperties. 展开更多
关键词 Bounded closed convex set drop property weak drop property.
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Non-deterministic fatigue life analysis using convex set models 被引量:5
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作者 SUN WenCai YANG ZiChun LI KunFeng 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第4期765-774,共10页
The non-probabilistic approach to fatigue life analysis was studied using the convex models-interval, ellipsoidal and multiconvex models. The lower and upper bounds of the fatigue life were obtained by using the secon... The non-probabilistic approach to fatigue life analysis was studied using the convex models-interval, ellipsoidal and multiconvex models. The lower and upper bounds of the fatigue life were obtained by using the second-order Taylor series and Lagrange multiplier method. The solving process for derivatives of the implicit life function was presented. Moreover, a median ellipsoidal model was proposed which can take into account the sample blind zone and almost impossibility of concurrence of some small probability events. The Monte Carlo method for multi-convex model was presented, an important alternative when the analytical method does not work. A project example was given. The feasibility and rationality of the presented approach were verified. It is also revealed that the proposed method is conservative compared to the traditional probabilistic method, but it is a useful complement when it is difficult to obtain the accurate probability densities of parameters. 展开更多
关键词 non-deterministic fatigue life convex set model NON-PROBABILISTIC Taylor expansion Monte Carlo
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On Proximinality of Convex Sets in Superspaces
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作者 Li Xin CHENG Zheng Hua LUO +1 位作者 Wen ZHANG Ben Tuo ZHENG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2016年第6期633-642,共10页
Abstract In this paper, we show that a closed convex subset C of a Banach space is strongly proximinal (proximinal, resp.) in every Banach space isometrically containing it if and only if C is locally (weakly, resp... Abstract In this paper, we show that a closed convex subset C of a Banach space is strongly proximinal (proximinal, resp.) in every Banach space isometrically containing it if and only if C is locally (weakly, resp.) compact. As a consequence, it is proved that local compactness of C is also equivalent to that for every Banach space Y isometrically containing it, the metric projection from Y to C is nonempty set-valued and upper semi-continuous. 展开更多
关键词 Proximinality convex set local compactness Banach space
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Lifts of Non-Compact Convex Sets and Cone Factorizations
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作者 WANG Chu ZHI Lihong 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2020年第5期1632-1655,共24页
This paper generalizes the factorization theorem of Gouveia,Parrilo and Thomas to a broader class of convex sets.Given a general convex set,the authors define a slack operator associated to the set and its polar accor... This paper generalizes the factorization theorem of Gouveia,Parrilo and Thomas to a broader class of convex sets.Given a general convex set,the authors define a slack operator associated to the set and its polar according to whether the convex set is full dimensional,whether it is a translated cone and whether it contains lines.The authors strengthen the condition of a cone lift by requiring not only the convex set is the image of an affine slice of a given closed convex cone,but also its recession cone is the image of the linear slice of the closed convex cone.The authors show that the generalized lift of a convex set can also be characterized by the cone factorization of a properly defined slack operator. 展开更多
关键词 Cone factorization convex set lift nonnegative rank POLYHEDRON positive semidefinite rank recession cone
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Calculus of Generalized Quasi-differentiable Functions I: Some Results on the Space of Pairs of Convex-Set Collections 被引量:3
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作者 张宏伟 张立卫 夏尊铨 《Northeastern Mathematical Journal》 CSCD 2003年第1期75-85,共11页
A Riesz space K1 whose elements are pairs of convex-set collections is presented for the study on the calculus of generalized quasi-differentiable functions. The space K1 is constructed by introducing a well-defined e... A Riesz space K1 whose elements are pairs of convex-set collections is presented for the study on the calculus of generalized quasi-differentiable functions. The space K1 is constructed by introducing a well-defined equivalence relation among pairs of collections of convex sets. Some important properties on the norm and operations in K1 are given. 展开更多
关键词 convex-set collection Riesz space quasi-differentiable function quasi-differential
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Homotopy Method for Non-convex Programming in Unbonded Set 被引量:4
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作者 徐庆 于波 《Northeastern Mathematical Journal》 CSCD 2005年第1期25-31,共7页
In the past few years, much and much attention has been paid to the method for solving non-convex programming. Many convergence results are obtained for bounded sets. In this paper, we get global convergence results f... In the past few years, much and much attention has been paid to the method for solving non-convex programming. Many convergence results are obtained for bounded sets. In this paper, we get global convergence results for non-convex programming in unbounded sets under suitable conditions. 展开更多
关键词 non-convex programming unbounded set interior homotopy global convergence
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The Ellipsoidal Invariant Set of Fractional Order Systems Subject to Actuator Saturation:The Convex Combination Form 被引量:1
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作者 Kai Chen Junguo Lu Chuang Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第3期311-319,共9页
The domain of attraction of a class of fractional order systems subject to saturating actuators is investigated in this paper. We show the domain of attraction is the convex hull of a set of ellipsoids. In this paper,... The domain of attraction of a class of fractional order systems subject to saturating actuators is investigated in this paper. We show the domain of attraction is the convex hull of a set of ellipsoids. In this paper, the Lyapunov direct approach and fractional order inequality are applied to estimating the domain of attraction for fractional order systems subject to actuator saturation. We demonstrate that the convex hull of ellipsoids can be made invariant for saturating actuators if each ellipsoid with a bounded control of the saturating actuators is invariant. The estimation on the contractively invariant ellipsoid and construction of the continuous feedback law are derived in terms of linear matrix inequalities (LMIs). Two numerical examples illustrate the effectiveness of the developed method. © 2014 Chinese Association of Automation. 展开更多
关键词 ALGEBRA Computational geometry Linear matrix inequalities Numerical methods Saturation (materials composition)
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MODELLING RANDOM CONVEX SETS
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作者 Lee Tzao-Lin ChenKeh-Wei RohanAttele 《Systems Science and Mathematical Sciences》 SCIE EI CSCD 1991年第2期111-127,共17页
A model is developed for convex-set valued data,which are the Minkowski sum of aconvex parameter set and a convex noise set.This model is generalized to include location and scaleparameters.A further generalization re... A model is developed for convex-set valued data,which are the Minkowski sum of aconvex parameter set and a convex noise set.This model is generalized to include location and scaleparameters.A further generalization results in a model for convex sets which is analogous to aone-way analysis of variance models.In each case,estimators of the parameters are given which,under certain conditions,are shown to be consistent.Data generated from the model and theestimators are studied.An outlier detection method is examined. 展开更多
关键词 Bandom convex set
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Optimality Conditions of the Set-valued Optimization Problem with Generalized Cone Convex Set-valued Maps Characterized by Contingent Epiderivative 被引量:2
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作者 Zhi-ang ZHOU Xin-min YANG Qiu-sheng QIU 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2018年第1期11-18,共8页
In this paper, firstly, a new notion of generalized cone convex set-valued map is introduced in real normed spaces. Secondly, a property of the generalized cone convex set-valued map involving the contingent epideriva... In this paper, firstly, a new notion of generalized cone convex set-valued map is introduced in real normed spaces. Secondly, a property of the generalized cone convex set-valued map involving the contingent epiderivative is obtained. Finally, as the applications of this property, we use the contingent epiderivative to establish optimality conditions of the set-valued optimization problem with generalized cone convex set-valued maps in the sense of Henig proper efficiency. The results obtained in this paper generalize and improve some known results in the literature. 展开更多
关键词 set-valued maps generalized cone convexity Henig proper efficiency contingent epiderivative optimality conditions
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Some Results on the Upper Convex Densities of the Self-Similar Sets at the Contracting-Similarity Fixed Points
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作者 Shaoyuan Xu Wangbin Xu Zuoling Zhou 《Analysis in Theory and Applications》 CSCD 2015年第1期92-100,共9页
In this paper, some results on the upper convex densities of self-similar sets at the contracting-similarity fixed points are discussed. Firstly, a characterization of the upper convex densities of self-similar sets a... In this paper, some results on the upper convex densities of self-similar sets at the contracting-similarity fixed points are discussed. Firstly, a characterization of the upper convex densities of self-similar sets at the contracting-similarity fixed points is given. Next, under the strong separation open set condition, the existence of the best shape for the upper convex densities of self-similar sets at the contracting-similarity fixed points is proven. As consequences, an open problem and a conjecture, which were posed by Zhou and Xu, are answered. 展开更多
关键词 Self-similar set upper convex density Hausdorff measure and Hausdorff dimension contracting-similarity fixed point.
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Inequalities for Tφ-convex functions 被引量:1
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作者 李世杰 赵灵芝 冷岗松 《Journal of Shanghai University(English Edition)》 CAS 2007年第2期142-147,共6页
In this paper, the Tφ-convex functions were introduced as a generalizations of convex functions. Then the characteristics of the Tφ-convex functions were discussed. Furthermore, some new inequalities for the Tφ-con... In this paper, the Tφ-convex functions were introduced as a generalizations of convex functions. Then the characteristics of the Tφ-convex functions were discussed. Furthermore, some new inequalities for the Tφ-convex functions were derived. 展开更多
关键词 Tφ-convex set convex function Tφ-convex function INEQUALITY
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CONVEX-MODEL ANALYSIS OF THE SEISMIC RESPONSE
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作者 何彩英 张景绘 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第10期941-947,共7页
An ellipsoidal Fourier-bound convex model (EFB model) is proposed in the present paper to express the uncertainty of seismic excitation, and several methods of selecting parameters of the model are explained. An analy... An ellipsoidal Fourier-bound convex model (EFB model) is proposed in the present paper to express the uncertainty of seismic excitation, and several methods of selecting parameters of the model are explained. An analytical expression is obtained for the worst response of the single-degree-of-freedom (SDOF) system with the EFB model. A numerical simulation shows that the traditional prediction of maximum response can yield the value substantially lover than that predicted by the EFB model. This means that the traditional designing method based on standard seismic inputs may lead to unsafe design decisions. 展开更多
关键词 seismic response response spectrum convex set extreme value
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SOME RESULTS ON BEST APPROXIMATION IN SPACES WITH CONVEX STRUCTURE
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作者 T. D. Narang 《Analysis in Theory and Applications》 2008年第1期67-73,共7页
Some generalizations of the result proved by S.P. Singh [J. Approx. Theory 25(1979), 89-90] are presented in convex metric spaces. The results proved contain several known results on the subject.
关键词 convex metric space convex set starshaped set non-expansive map affinemap
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Higher Order Strongly Biconvex Functions and Biequilibrium Problems
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作者 Muhammad Aslam Noor Khalida Inayat Noor 《Advances in Linear Algebra & Matrix Theory》 2021年第2期31-53,共23页
In this paper, we introduce and study some new classes of biconvex functions with respect to an arbitrary function and a bifunction, which are called the higher order strongly biconvex functions. These functions are n... In this paper, we introduce and study some new classes of biconvex functions with respect to an arbitrary function and a bifunction, which are called the higher order strongly biconvex functions. These functions are nonconvex functions and include the biconvex function, convex functions, and <i>k</i>-convex as special cases. We study some properties of the higher order strongly biconvex functions. Several parallelogram laws for inner product spaces are obtained as novel applications of the higher order strongly biconvex affine functions. It is shown that the minimum of generalized biconvex functions on the <i>k</i>-biconvex sets can be characterized by a class of equilibrium problems, which is called the higher order strongly biequilibrium problems. Using the auxiliary technique involving the Bregman functions, several new inertial type methods for solving the higher order strongly biequilibrium problem are suggested and investigated. Convergence analysis of the proposed methods is considered under suitable conditions. Several important special cases are obtained as novel applications of the derived results. Some open problems are also suggested for future research. 展开更多
关键词 Biconvex Functions convex Functions -convex Functions -convex sets Parallelogram Laws Biequilibrium Problems Bivariational Inequalities Iterative Methods Convergence Analysis
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SOME PROPERTIES OF BOUNDED SETS IN INDUCTIVE LIMITS
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作者 丘京辉 《苏州大学学报(自然科学版)》 CAS 1991年第2期109-114,共6页
Let (E,ξ)=indlim (En,ξn) be an inductive limit of a sequence of locally convex spaces,For brevity,denote by (DS) each set Bbounded in (E,ξ) is contained in some En; and (DST) each set B bounded in (E,ξ) is co... Let (E,ξ)=indlim (En,ξn) be an inductive limit of a sequence of locally convex spaces,For brevity,denote by (DS) each set Bbounded in (E,ξ) is contained in some En; and (DST) each set B bounded in (E,ξ) is contained and bounded in some (En,ξn). Theovem 1.(DS) holds provided that (i) for each n∈N,there is a neighborhood Un of o in (En,ξn) and m(n)∈ such that -↑Un^E包含于Em(n),and (ii) for any neighborhood V n of o in (En,ξn),∞↑Un=1 Vn absorbs every bounded set in (E,ξ). theorem 2 Let all (En,ξn) be metrizable and (DS) hold,then for each bounded set B IN (E,ξ)and each n ∈N thcrc is a neighborhood U k of o in (Ek,ξk), 1≤k≤n ,and m(n)∈N such that ——↑(B+U1+U2+…+Un)^E包含于 Em(n). theorem 3. Let all (En,ξn) be Frechet spaces.Then (DST) holds if and only if (i) for each n ∈N,there is u neighborhood U n of in (En,ξn) and m(n)∈N such that 0↑Un^E包含于Em(n),and (ii) for each each closed ,absosed,absolutely conuex,bounded set B in (E,ξ),∞↑Un=1((εnB)∩Un)absorbs B,where U n is any neighborhood of o in (En,ξn) and εn is any positive number for every n ∈N。 展开更多
关键词 有界集 归纳极限 凸空间 线性拓扑空间
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