共查询到20条相似文献,搜索用时 31 毫秒
1.
Ronald R. Yager 《Fuzzy Optimization and Decision Making》2017,16(1):1-21
We describe the Dempster–Shafer belief structure and provide some of its basic properties. We introduce the plausibility and belief measures associated with a belief structure. We note that these are not the only measures that can be associated with a belief structure. We describe a general approach for generating a class of measures that can be associated with a belief structure using a monotonic function on the unit interval, called a weight generating function. We study a number of these functions and the measures that result. We show how to use weight-generating functions to obtain dual measures from a belief structure. We show the role of belief structures in representing imprecise probability distributions. We describe the use of dual measures, other then plausibility and belief, to provide alternative bounding intervals for the imprecise probabilities associated with a belief structure. We investigate the problem of decision making under belief structure type uncertain. We discuss two approaches to this decision problem. One of which is based on an expected value of the OWA aggregation of the payoffs associated with the focal elements. The second approach is based on using the Choquet integral of a measure generated from the belief structure. We show the equivalence of these approaches. 相似文献
2.
We study the almost periodic solutions of Euler equations and of some more general Difference Equations. We consider two different notions of almost periodic sequences, and we establish some relations between them. We build suitable sequences spaces and we prove some properties of these spaces. We also prove properties of Nemytskii operators on these spaces. We build a variational approach to establish existence of almost periodic solutions as critical points, We obtain existence theorems fornonautonomous linear equations and for an Euler equation with a concave and coercive Lagrangian. We also use a Fixed Point approach to obtain existence results for quasi-linear Difference Equations. 相似文献
3.
We describe the type of reasoning used in the typical fuzzy logic controller, the Mamdani reasoning method. We point out the basic assumptions in this model. We discuss the S-OWA operators which provide families of parameterized “andlike” and “orlike” operators. We generalize the Mamdani model by introducing these operators. We introduce a method, which we call Direct Fuzzy Reasoning (DFR), which results from one choice of the parameters. We develop some learning algorithms for the new method. We show how the Takagi-Sugeno-Kang (TSK) method of reasoning is an example of this DFR method. 相似文献
4.
Hande Yaman 《Mathematical Programming》2006,106(2):365-390
We consider the vehicle routing problem where one can choose among vehicles with different costs and capacities to serve the
trips. We develop six different formulations: the first four based on Miller-Tucker-Zemlin constraints and the last two based
on flows. We compare the linear programming bounds of these formulations. We derive valid inequalities and lift some of the
constraints to improve the lower bounds. We generalize and strengthen subtour elimination and generalized large multistar
inequalities. 相似文献
5.
We apply the theory of fuzzy subsets to the multiple objective decision problem of stock selection. We allow our objectives to have varying degrees of importance. We discuss various criteria used in selecting stocks. We indicate some procedures for subjectively evaluating the membership functions associated with these criteria. 相似文献
6.
Rose-Anne Dana 《Annals of Operations Research》2002,114(1-4):105-115
We discuss the existence and the qualitative properties of equilibria when agents have multiple priors and there is only one good in each state of the world. We first prove a general existence result in infinite dimension economies. We then fully describe the equilibria in two special cases. We first consider the case of CEU maximizers that have same capacities. We next consider the case of no aggregate uncertainty. We prove that if agents have non-random initial endowments and are uncertainty averse and maximize the minimal expected utility according to a set of possible priors, then the existence of a common prior is equivalent to the existence of a unique equilibrium, the no-trade equilibrium. We lastly give a mild assumption for indeterminacy of equilibria and compute the dimension of indeterminacy. 相似文献
7.
A. L. Kuzemsky 《Theoretical and Mathematical Physics》2018,194(1):30-56
We consider some principal problems of nonequilibrium statistical thermodynamics in the framework of the Zubarev nonequilibrium statistical operator approach. We present a brief comparative analysis of some approaches to describing irreversible processes based on the concept of nonequilibrium Gibbs ensembles and their applicability to describing nonequilibrium processes. We discuss the derivation of generalized kinetic equations for a system in a heat bath. We obtain and analyze a damped Schrödinger-type equation for a dynamical system in a heat bath. We study the dynamical behavior of a particle in a medium taking the dissipation effects into account. We consider the scattering problem for neutrons in a nonequilibrium medium and derive a generalized Van Hove formula. We show that the nonequilibrium statistical operator method is an effective, convenient tool for describing irreversible processes in condensed matter. 相似文献
8.
Pádraig Kirwan 《Mathematische Nachrichten》2001,231(1):39-68
We study various methods of complexifying real normed spaces. We see how the notions of duality and complexification are interchangeable. We obtain estimates for the norms of complexified multilinear mappings and polynomials. We see how polynomials can be complexified without reference to the associated multilinear mappings. 相似文献
9.
We discuss the use of monotonic set measures for the representation of uncertain information. We look at some important examples of measure-based uncertainty, specifically probability and possibility and necessity. Others types of uncertainty such as cardinality based and quasi-additive measures are discussed. We consider the problem of determining the representative value of a variable whose uncertain value is formalized using a monotonic set measure. We note the central role that averaging and particularly weighted averaging operations play in obtaining these representative values. We investigate the use of various integrals such as the Choquet and Sugeno for obtaining these required averages. We suggest ways of extending a measure defined on a set to the case of fuzzy sets and the power sets of the original set. We briefly consider the problem of question answering under uncertain knowledge. 相似文献
10.
We study a free boundary problem for the Laplace operator, where we impose a Bernoulli-type boundary condition. We show that there exists a solution to this problem. We use A. Beurling’s technique, by defining two classes of sub- and super-solutions and a Perron argument. We try to generalize here a previous work of A. Henrot and H. Shahgholian. We extend these results in different directions. 相似文献
11.
Przemys?aw Górka 《Journal of Mathematical Analysis and Applications》2008,341(2):1413-1426
We examine the evolution of crystals in three dimensions. We assume that the Wulff shape is a prism with a hexagonal base. We include the Gibbs-Thomson law on the crystal surface and the so-called Stefan condition. We show local in time existence of solutions assuming that the initial crystal has admissible shape. 相似文献
12.
Shuji Machihara 《Journal of Mathematical Analysis and Applications》2003,281(2):552-564
We study the inviscid limit of the complex Ginzburg-Landau equation. We observe that the solutions for the complex Ginzburg-Landau equation converge to the corresponding solutions for the nonlinear Schrödinger equation. We give its convergence rate. We estimate the integral forms of solutions for two equations. 相似文献
13.
N. S. Walton 《Queueing Systems》2011,68(1):51-60
We describe a queuing model where service is allocated as a function of queue sizes. We consider allocations policies that
are insensitive to service requirements and have a maximal stability region. We take a limit where the queuing model becomes
congested. We study how service is allocated under this limit. We demonstrate that the only possible limit allocation is one
that maximizes a proportionally fair optimization problem. 相似文献
14.
ABSTRACTWe study the inverse problem of identifying a variable parameter in variational and quasi-variational inequalities. We consider a quasi-variational inequality involving a multi-valued monotone map and give a new existence result. We then formulate the inverse problem as an optimization problem and prove its solvability. We also conduct a thorough study of the inverse problem of parameter identification in noncoercive variational inequalities which appear commonly in applied models. We study the inverse problem by posing optimization problems using the output least-squares and the modified output least-squares. Using regularization, penalization, and smoothing, we obtain a single-valued parameter-to-selection map and study its differentiability. We consider optimization problems using the output least-squares and the modified output least-squares for the regularized, penalized and smoothened variational inequality. We give existence results, convergence analysis, and optimality conditions. We provide applications and numerical examples to justify the proposed framework. 相似文献
15.
V. A. Andreev D. M. Davidović L. D. Davidović Milena D. Davidović Miloš D. Davidović 《Theoretical and Mathematical Physics》2017,192(1):1080-1096
We consider scale transformations (q, p) → (λq, λp) in phase space. They induce transformations of the Husimi functions H(q, p) defined in this space. We consider the Husimi functions for states that are arbitrary superpositions of n-particle states of a harmonic oscillator. We develop a method that allows finding so-called stretched states to which these superpositions transform under such a scale transformation. We study the properties of the stretched states and calculate their density matrices in explicit form. We establish that the density matrix structure can be described using negative binomial distributions. We find expressions for the energy and entropy of stretched states and calculate the means of the number-ofstates operator. We give the form of the Heisenberg and Robertson–Schrödinger uncertainty relations for stretched states. 相似文献
16.
《Differential Geometry and its Applications》2001,14(3):217-234
We study the existence of special metrics on compact complex manifolds. We show that every considered metric can be caracterized using conditions on the space of positive currents. We investigate what happens under holomorphic submersions or modifications. We show which metrics exist on some classical examples. 相似文献
17.
Fernanda Botelho 《Linear algebra and its applications》2010,432(1):275-282
We characterize essential normality for certain elementary operators acting on the Hilbert-Schmidt class. We find the Aluthge transform of an elementary operator of length one. We show that the Aluthge transform of an elementary 2-isometry need not be a 2-isometry. We also characterize hermitian elementary operators of length 2. 相似文献
18.
Cographs from the minimal family of graphs containing K1 which are closed with respect to complements and unions. We discuss vertex partitions of graphs into the smallest number of cographs, where the partition is as small as possible. We shall call the order of such a partition the c-chromatic number of the graph. We begin by axiomatizing several well-known graphical parameters as motivation for this function. We present several bounds on c-chromatic number in terms of well-known expressions. We show that if a graph is triangle-free, then its chromatic number is bounded between the c-chromatic number and twice this number. We show both bounds are sharp, for graphs with arbitrarily high girth. This provides an alternative proof to a result in [3]; there exist triangle-free graphs with arbitrarily large c-chromatic numbers. We show that any planar graph with girth at least 11 has a c-chromatic number of at most two. We close with several remarks on computational complexity. In particular, we show that computing the c-chromatic number is NP-complete for planar graphs. 相似文献
19.
We consider the problem of the dissipative dynamics of a harmonic oscillator linearly coupled to a heat bath. We demonstrate
that in addition to the mean energy, there exists an infinite series of quantities exponentially decreasing in time that are
means of polynomials of the system Hamiltonian. We obtain the spectrum of the corresponding relaxation times. We propose a
method for representing the time characteristics of the system in terms of operators corresponding to the exponentially damped
observables. We obtain a recurrence relation for these operators. 相似文献
20.
We consider a fully discrete implicit finite-element approximationof a model for the phase separation of a multi-component alloy.We prove existence, uniqueness and stability of the numericalsolution for a sufficiently small time step. We prove convergenceto the solution of the associated continuous problem. We performa linear stability analysis of the equation and describe somenumerical experiments. 相似文献