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1.
In [2], general approximation results for the solution in a neighborhood of a simple limit point are given. In this paper we give projective approximation results for the solutions in a neighborhood of a double limit point. Application of these results to a nonlinear partial differential equation and numerical results are given.  相似文献   

2.
We will show that some of the superconvergence properties for the mixed finite element method for elliptic problems are preserved in the mixed semi-discretizations for a diffusion equation and for a Maxwell equation in two space dimensions. With the help of mixed elliptic projection we will present estimates global and pointwise in time. The results for the Maxwell equations form an extension of existing results. For both problems, our results imply that post-processing and a posteriori error estimation for the error in the space discretization can be performed in the same way as for the underlying elliptic problem.  相似文献   

3.
In this paper, we introduce a system of quasi-variational relations (in short, SQVR) and present several examples which show that it is a very general and unified model of several problems. We establish the existence of solutions of SQVP, in general, and several other problems, in particular. As an application of our results, we derive maximal element theorems and a collectively fixed point theorem for a family of multivalued maps. As further applications, we study Ky Fan type inequality / inclusion problem for vector valued bifunctions which includes constrained Nash equilibrium problem as a special case. We also present a common fixed point theorem for a family of multivalued maps. The results of this paper improve and generalize several known results on (system of) quasi-equilibrium problems, (system of) quasi-variational inclusions, constrained Nash equilibrium problem, collectively fixed point theorem and KKM type theorems for a family of multivalued maps. Our results also contain several results which appeared in recent literature.  相似文献   

4.
Properties of serial kanban systems   总被引:1,自引:0,他引:1  
In this paper we show some structural results of a kanban system by using results about the underlying GSMP. The main results from this connection are: dominance of allocations, optimal partition, upper and lower bounds on throughput, consistency of the IPA derivative, convexity of throughput as a function of service time parameters and concavity of throughput with respect to number of kanbans. Although the dominance and the partition results were obtained previously by sample path arguments, the proofs here are less cumbersome and generalize the earlier results. The second-order properties for kanban lines are new. These results form a basis for results in multi-product lines where proofs by sample paths require extensive notation.  相似文献   

5.
In this article, we introduce a new approach for proving Maximum Principle type results for viscosity solutions of second-order, fully nonlinear possibly degenerate elliptic equations. This approach leads, in particular, to a better understanding of the conditions on the equation which are necessary to obtain such results. It allows us to provide new comparison results for semilinear and quasilinear equations.  相似文献   

6.
In informationally inefficient markets, classical decision theory assumes the value of information to be positive. Recent developments, however, contradict this paradigm. Schredelseker [Schredelseker, K., 2001. Is the usefulness approach useful? Some reflections on the utility of public information. In: McLeay, S., Riccaboni, A. (Eds.), Contemporary Issues in Accounting Regulation, Kluwer Academic Publishers, Boston, pp. 135–153] proposed a simulation model wherein a single security is traded among non-cooperating and asymetrically informed traders. One of the main results was the fact that badly informed traders could expect higher returns than traders with more information. But Schredelseker was able to give exact results for a small number of traders only. The aim of this paper is to give reliable results for a sufficiently large number of traders for both the expected gain and the probability of gain larger than zero. We are using combinatorial methods in order to get exact results for badly informed traders and simulation techniques for results of traders with higher level of information. The exact results are used (error between exact results and simulation results for the first traders) to determine the number of samples which have to be drawn with the simulation algorithm.  相似文献   

7.
杨志林  魏耿平 《数学学报》2007,50(2):363-372
运用锥拉伸与压缩不动点定理,研究一类泛函积分方程的正解.把所得结果应用于研究常微分方程积分边值问题正解的存在性,所得结果推广和本质上改进了马如云等作者最近的一些结果.  相似文献   

8.
The steady solution of a solitary wave propagating in the presence of a linear shear background current is investigated by the Green–Naghdi (GN) equations. The steady solution is obtained by use of the Newton–Raphson method. Three aspects are investigated; they are the wave speed, wave profile and velocity field. The converged GN results are compared with results from the literature. It is found that for the opposing-current case of the solitary wave with a small amplitude, the results of the GN equations match results from the literature well, while for the solitary wave with a large amplitude, results from the literature are seen to be not as accurate. In the following-current case, though the amplitude of the solitary wave is small, the GN results are shown to be accurate. The velocity along the water column at the wave crest and the velocity field for different cases are calculated by the GN equations. The results of the GN equations show obvious differences when compared with the results obtained by superposing the no-current results and linear shear current linearly. We find that for the same current strength, the vortex is stronger for the steep solitary-wave case than that for the small solitary-wave case.  相似文献   

9.
In this paper, we present some Farkas-type results for a fractional programming problem. To this end, by using the properties of dualizing parametrization functions, Lagrangian functions and the epigraph of the conjugate functions, we introduce some new notions of regularity conditions and then obtain some dual forms of Farkas-type results for this fractional programming problem. We also obtain sufficient conditions for alternative type theorems. As an application of these results, we obtain the corresponding results for a convex optimization problem.  相似文献   

10.
The paper contains exponential inequalities for dependent random variables. As a measure of dependence we use φand ρ-mixing coefficients, the last one being based on the maximal coefficient of correlation. These results allow us to study the problem of uniform strong convergence for the kernel estimators of a density and for a kernel predictor for stochastic processes. Our uniform consistency theorems extend some known results  相似文献   

11.
Optimality conditions, duality and converse duality results are obtained for a class of continuous programming problems with a nondifferentiable term in the integrand of the objective function. The proofs are based on a Fritz John theorem for constrained optimization in abstract spaces. The results generalize various well-known results in variational problems with differentiable functions, and also give a dynamic analogue of certain nondifferentiable programming problems.  相似文献   

12.
Cyclic cutwidth minimization problem (CCMP) consists of embedding a graph onto a circle such that the maximum cutwidth in a region is minimized. It is an NP-complete problem and for some classes of graphs, exact results of cyclic cutwidth have been proved in literature. However, no algorithm has been reported for general graphs. In this paper, a memetic algorithm is proposed for CCMP in which we have designed six construction heuristics in order to generate a good initial population and also local search is employed to improve the solutions in each generational phase. The algorithm achieves optimal results for the classes of graphs with known exact results. Extensive experiments have also been conducted on some classes of graphs for which exact results are not known such as the complete split graph, join of hypercubes, toroidal meshes, cone graph and some instances of Harwell-Boeing graphs which are a subset of public domain Matrix Market library. Trends observed in the experimental results for some of the classes of graphs have led to conjectures for cyclic cutwidth.  相似文献   

13.
We prove rigidity type results on the vanishing of stable Ext and Tor for modules of finite complete intersection dimension, results which generalize and improve upon known results. We also introduce a notion of pre-rigidity, which generalizes phenomena for modules of finite complete intersection dimension and complexity one. Using this concept, we prove results on length and vanishing of homology modules.  相似文献   

14.
In this paper, necessary and sufficient conditions for the asymptotic behaviour of all bounded solutions of a class of nonlinear higher-order neutral dynamic equations are stated related to various ranges of the coefficient associated with the neutral part, in one of which the coefficient is allowed to oscillate and not tend to zero asymptotically. The new results improve and generalize the known results stated for difference equations and differential equations, and answer some problems left open for the case for arbitrary time scales. Some certain examples, which the results in the literature fail to deliver an answer to, are given to illustrate the applicability and significance of the new results.  相似文献   

15.
B值随机元阵列的完全收敛性及大数定律   总被引:6,自引:1,他引:5  
该文在随机元阵列随机有界于某非负随机变量的条件下,得到了B值随机元阵列完全收敛性的一般性结论,并讨论了随机元阵列加权和的收敛性,使[5][6]中的结果得到了改进和推广.同时讨论了完全收敛性与Banach空间p型(1<P≤2)性质的等价性,使[14],[15]中的结果得到进一步的改进.  相似文献   

16.
Basic design principles of the architecture of a dynamic visualization system for multiprocessor computers with common memory are described. Analysis of the results of calculation of 3D nonstationary multivortical turbulent flows of viscous fluids and gases is performed for the systems whose behavior can be analyzed using the Navier-Stokes and difference methods involving grids with several millions of nodes. Such a large number of nodes results from a great complexity of the vortical structures arising and changing in the process of calculation. The software tools necessary for the analysis of the results are considered and a technique of interaction between a supercomputer and the workstation used for visualization is proposed. As an example, a procedure for processing of the calculation results obtained from the numerical investigation of 3D nonstationary flows of a viscous incompressible fluid in a channel with a square cross section is presented.  相似文献   

17.
In the present paper we prove new results for a general perturbation theory for nonlinear mappings between metric spaces. Using these results we are able to establish new principles for the treatment of nonlinear initial-value problems by difference methods. The main results are the characterization of the existence of discrete limits of sequences of mappings and the characterization of the existence of generalized solutions of nonlinear initial-value problems which are limits of solutions of difference equations. As conclusions one obtains generalizations of Lax's equivalence theorem for nonlinear and linear initial-value problems and a convergence theorem for a concrete hyperbolic equation.  相似文献   

18.
1981年,1985年,2000年,乔三正、蔡东汉、魏益民分别给出Drazin广义逆不同形式的表示.本文将对上述结果进行推广,给出Drazin广义逆的统一表示,使上述三个结果均成为本文主要结果的特例.在本文主要结果的基础上,利用算子谱理论,给出Drazin广义逆的一种逼近形式的表示,同时给出逼近解的估计.此结果推广了蔡东汉、魏益民的相应结果.  相似文献   

19.
We establish duality and vanishing results for the cohomology of the Weil group of a p-adic field. Among them is a duality theorem for finitely generated modules, which implies Tate–Nakayama Duality. We prove comparison results with Galois cohomology, which imply that the cohomology of the Weil group determines that of the Galois group. When the module is defined by an abelian variety, we use these comparison results to establish a duality theorem analogous to Tate?s duality theorem for abelian varieties over p-adic fields.  相似文献   

20.
Existence results for maximum likelihood Nash equilibria for random games were given by Borm, Cao and García-Jurado, and by Voorneveld. Here we discuss the relationship of those results with ordinary existence results for Nash equilibria, a traditional subject in game theory.  相似文献   

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