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排序方式: 共有2369条查询结果,搜索用时 15 毫秒
91.
Let a open subset of
n
, n3, and
an open. Existence and unicity are proved for the Dirichlet problem
It is assumed that the linear part of satisfy the conditions of Hervé, (·,u,u): ××
n
satisfy Carathéodory's condition and structure conditions (H1), (H2) and (H3) below. Let H denote the sheaf of L-solutions, we prove that (,H) is a nonlinear Bauer harmonic space. 相似文献
92.
S. Rutkauskas 《Lithuanian Mathematical Journal》2001,41(3):282-291
We consider Dirichlet–type problems for weakly connected systems of elliptic equations of second order with a strong degeneracy at an inner point of the domain, when, in a neighborhood of this point, the asymptotics of a solution is additionally given. The form of the given asymptotics essentially depends on the properties of the coefficients at the first–order derivatives. We prove the existence and uniqueness of solutions of the problems considered in Hölder function classes. 相似文献
93.
We consider a Dirichlettype problem for a system of elliptic equations of second order with a strong degeneracy at an inner point of the domain, when, in a neighborhood of this point, the principal term of the asymptotics of a solution is additionally given. We prove the existence and uniqueness of a solution of the problem considered in a weighted class of Hölder vector functions. 相似文献
94.
In the paper, a limit theorem in the sense of the weak convergence of probability measures in the space of meromorphic functions for general Dirichlet series is proved. 相似文献
95.
We prove the following theorem. Let m and n be any positive integers with mn, and let
be a subset of the n-dimensional Euclidean space
n
. For each i=1, . . . , m, there is a class
of subsets M
i
j
of
Tn
. Assume that
for each i=1, . . . , m, that M
i
j
is nonempty and closed for all i, j, and that there exists a real number B(i, j) such that
and its jth component
xjB(i, j)
imply
. Then, there exists a partition
of {1, . . . , n} such that
for all i and
We prove this theorem based upon a generalization of a well-known theorem of Birkhoff and von Neumann. Moreover, we apply this theorem to the fair allocation problem of indivisible objects with money and obtain an existence theorem. 相似文献
96.
In [2] E. Dobrowolski and K.S. Williams considered a problem of obtaining estimates for the sum
n=a+1
a+N
f(n),for a certain class of functions f. One specific application of their result is a new method for estimating character sums. In particular, they obtain a form of the Pólya-Vinogradov inequality with the constant 1/(2 log 2). In this note we improve their estimates and obtain, in particular, a form of the Pólya-Vinogradov inequality with the constant 1/(3 log 3). A nice feature of our estimate is that it is obtained by a very simple argument. 相似文献
97.
关于调和映照的一个 Liouville型定理 总被引:2,自引:2,他引:0
张希 《浙江大学学报(理学版)》2000,27(2):124-127
本文证明了完备非紧 Riemann流形 M,若其上不存在非常数、具有限 Dirichlet积分的调和函数 , 则从 M出发到任何 C-H流形的具有限能量的调和映照必为常值映照. 相似文献
98.
Simulation optimization of buffer allocations in production lines with unreliable machines 总被引:3,自引:0,他引:3
Gül Gürkan 《Annals of Operations Research》2000,93(1-4):177-216
We use a recent simulationbased optimization method, sample path optimization, to find optimal buffer allocations in tandem production lines where machines are subject to random breakdowns and repairs, and the product is fluidtype. We explore some of the functional properties of throughput of such systems and exploit these properties to prove the almost sure convergence of our optimization technique, under a regularity condition on the steady state. Utilizing a generalized semiMarkov process (GSMP) representation of the system, we derive recursive expressions to compute onesided directional derivatives of throughput, from a single simulation run. Finally, we give computational results for lines with up to 50 machines. We also compare results for smaller lines with the results from a more conventional method, stochastic approximation, whenever applicable. In these numerical studies, our method performed quite well on problems that are considered difficult by current computational standards. 相似文献
99.
G. Malescio 《Physica A》2007,383(2):643-650
We present a model describing a generic process in which a finite resource is partitioned and distributed among agents. Through numerical simulation we show that the model considered is able to originate, within a unifying approach, a variety of broad distributions and provides an interpretation of empirical properties of distributions observed in the real world. In particular it allows to relate the exponent of the power-law part of the distributions to resource abundance and accessibility, while the left-end exponential behavior, observed in many distributions, is related to the presence of dissipative effects. 相似文献