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991.
Keomkyo Seo 《Mathematische Nachrichten》2012,285(10):1264-1273
Let C be a closed convex set in a complete simply connected Riemannian manifold M with sectional curvature bounded above by a positive constant K. Assume that Σ is a compact minimal surface outside C such that Σ is orthogonal to ?C along ?Σ∩?C and ?Σ ~ ?C is radially connected from a point p ∈ ?Σ∩?C. We introduce a modified volume Mp(Σ) of Σ and obtain a sharp isoperimetric inequality where equality holds if and only if Σ is a geodesic half disk with constant Gaussian curvature K. We also prove higher dimensional isoperimetric inequalities for minimal submanifolds outside a closed convex set in a Riemannian manifold using the modified volume. 相似文献
992.
A series of end‐functionalized poly(trimethylene carbonate) DNA carriers, characterized by low cationic charge density and pronounced hydrophobicity, is used to study structural effects on in vitro gene delivery. As the DNA‐binding moieties are identical in all polymer structures, the differences observed between the different polymers are directly related to the functionality and length of the polymer backbone. The transfection efficiency and cytotoxicity of the polymer/DNA complexes are thus found to be dependent on a combination of polymer charge density and functionality, highlighting the importance of such structural considerations in the development of materials for efficient gene delivery.
993.
This paper sets the scene for discrete variational problems on an abstract cellular complex that serves as discrete model of Rp and for the discrete theory of partial differential operators that are common in the Calculus of Variations. A central result is the construction of a unique decomposition of certain partial difference operators into two components, one that is a vector bundle morphism and other one that leads to boundary terms. Application of this result to the differential of the discrete Lagrangian leads to unique discrete Euler and momentum forms not depending either on the choice of reference on the base lattice or on the choice of coordinates on the configuration manifold, and satisfying the corresponding discrete first variation formula. This formula leads to discrete Euler equations for critical points and to exact discrete conservation laws for infinitesimal symmetries of the Lagrangian density, with a clear physical interpretation. 相似文献
994.
Truong Xuan Duc Ha 《Nonlinear Analysis: Theory, Methods & Applications》2012,75(3):1305-1323
We present a new approach to the study of a set-valued equilibrium problem (for short, SEP) through the study of a set-valued optimization problem with a geometric constraint (for short, SOP) based on an equivalence between solutions of these problems. As illustrations, we adapt to SEP enhanced notions of relative Pareto efficient solutions introduced in set optimization by Bao and Mordukhovich and derive from known or new optimality conditions for various efficient solutions of SOP similar results for solutions of SEP as well as for solutions of a vector equilibrium problem and a vector variational inequality.We also introduce the concept of quasi weakly efficient solutions for the above problems and divide all efficient solutions under consideration into the Pareto-type group containing Pareto efficient, primary relative efficient, intrinsic relative efficient, quasi relative efficient solutions and the weak Pareto-type group containing quasi weakly efficient, weakly efficient, strongly efficient, positive properly efficient, Henig global properly efficient, Henig properly efficient, super efficient and Benson properly efficient solutions. The necessary conditions for Pareto-type efficient solutions and necessary/sufficient conditions for weak Pareto-type efficient solutions formulated here are expressed in terms of the Ioffe approximate coderivative and normal cone in the Banach space setting and in terms of the Mordukhovich coderivative and normal cone in the Asplund space setting. 相似文献
995.
In this paper we establish new generalized differentiation rules in general Banach spaces regarding normal cones to set images under functions, coderivatives of compositions of set-valued mappings, as well as calculus results for normal compactness of sets and their images. In addition to the metric regularity of mappings, our results involve tangential distances of sets for which we also provide a fairly complete study by exploring its variations, basic properties, as well as relations to similar notions. Some related results are also established. 相似文献
996.
Ricardo Almeida Shakoor Pooseh Delfim F.M. Torres 《Nonlinear Analysis: Theory, Methods & Applications》2012,75(3):1009-1025
We obtain necessary optimality conditions for variational problems with a Lagrangian depending on a Caputo fractional derivative, a fractional and an indefinite integral. Main results give fractional Euler-Lagrange type equations and natural boundary conditions, which provide a generalization of the previous results found in the literature. Isoperimetric problems, problems with holonomic constraints and depending on higher-order Caputo derivatives, as well as fractional Lagrange problems, are considered. 相似文献
997.
A. Barbagallo 《Nonlinear Analysis: Theory, Methods & Applications》2012,75(3):1104-1123
An evolutionary model for a multi-sector, multi-instrument financial equilibrium problem, with a general utility function, different prices for assets and liabilities and including the expenses for the management of the financial institutions is presented. In this general case, we give the evolutionary financial equilibrium conditions and prove their equivalence with an evolutionary variational inequality, from which existence results of the financial equilibrium follow. Moreover, making use of new nonlinear analysis results, we develop a Lagrange theory which allows one to study the behaviour of the financial equilibrium by means of the Lagrange multipliers. As a product of this analysis, we prove that for the financial model an equilibrium law together with a liability formula must be fulfilled, from which the reorganization of the existing financial disequilibrium depends. 相似文献
998.
The proximal average of a finite collection of convex functions is a parameterized convex function that provides a continuous transformation between the convex functions in the collection. This paper analyzes the dependence of the optimal value and the minimizers of the proximal average on the weighting parameter. Concavity of the optimal value is established and implies further regularity properties of the optimal value. Boundedness, outer semicontinuity, single-valuedness, continuity, and Lipschitz continuity of the minimizer mapping are concluded under various assumptions. Sharp minimizers are given further attention. Several examples are given to illustrate our results. 相似文献
999.
1000.
Optimal control of various variational problems has been an area of active research. On the other hand, in recent years many important models in mechanics and economics have been formulated as multi-valued quasi variational inequalities. The primary objective of this work is to study optimal control of the general nonlinear problems of this type. Under suitable conditions, we ensure the existence of an optimal control for a quasi variational inequality with multivalued pseudo-monotone maps. Convergence behavior of the control is studied when the data for the state quasi variational inequality is contaminated by some noise. Some possible applications are discussed. 相似文献