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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
981.
Consider the variational integral
where Ω⊂ℝ
n
andp≥n≥2. H: (0, ∞)→[0, ∞) is a smooth convex function such that
. We approximateJ by a sequence of regularized functionalsJ
δ whose minimizers converge strongly to anJ-minimizing function and prove partial regularity results forJ
δ-minimizers. 相似文献
982.
Summary Let (W, H, ) be an abstract Wiener space and letR(w) be a strongly measurable random variable with values in the set of isometries onH. Suppose that Rh is smooth in the Sobolev sense and that it is a quasi-nilpotent operator onH for everyhH. It is shown that (R(w)h) is again a Gaussian (0, |h|
H
2
)-random variable. Consequently, if (e
i
,i)W
* is a complete, orthonormal basis ofH, then
defines a measure preserving transformation, a rotation, onW. It is also shown that if for some strongly measurable, operator valued (onH) random variableR, (R(w+k)h) is (0, |h|
H
2
)-Gaussian for allk, hH, thenR is an isometry and Rh is quasi-nilpotent for allHH. The relation between the stochastic calculi for these Wiener pathsw and
, as well as the conditions of the inverbibility of the map
are discussed and the problem of the absolute continuity of the image of the Wiener measure under Euclidean motion on the Wiener space (i.e.
composed with a shift) is studied.The research of the second author was supported by the Fund for the Promotion of Research at the TechnionDedicated to the memory of Albert Badrikian 相似文献
983.
Karin Krüger Natalia V. Shakhlevich Yuri N. Sotskov Frank Werner 《The Journal of the Operational Research Society》1995,46(12):1481-1497
We consider a scheduling problem where a set of n jobs has to be processed on a set of m machines and arbitrary precedence constraints between operations are given. Moreover, for any two operations i and j values a ij >0 and a ji >0 may be given where a ij is the minimal difference between the starting times of operations i and j when operation i is processed first. Often, the objective is to minimize the makespan but we consider also arbitrary regular criteria. Even the special cases of the classical job shop problem J//Cmax belong to the set of NP-hard problems. Therefore, approximation or heuristic algorithms are necessary to handle large-dimension problems. Based on the mixed graph model we give a heuristic decomposition algorithm for such a problem, i.e. the initial problem is partitioned into subproblems that can be solved exactly or approximately with a small error bound. These subproblems are obtained by a relaxation of a subset of the set of undirected edges of the mixed graph. The subproblems are successively solved and a proportion of the results obtained for one subproblem is kept for further subproblem definitions. Numerical results of the algorithm presented here are given. 相似文献
984.
Under the assumptions thatq is not a root of unity and that the differentialsdu
j
i
of the matrix entries span the left module of first order forms, we classify bicovariant differential calculi on quantum groupsA
n–1
,B
n
,C
n
andD
n
. We prove that apart one dimensional differential calculi and from finitely many values ofq, there are precisely2n such calculi on the quantum groupA
n–1
=SL
q
(n) forn3. All these calculi have the dimensionn
2. For the quantum groupsB
n
,C
n
andD
n
we show that except for finitely manyq there exist precisely twoN
2-dimensional bicovariant calculi forN3, whereN=2n+1 forB
n
andN=2n forC
n
,D
n
. The structure of these calculi is explicitly described and the corresponding ad-invariant right ideals of ker are determined. In the limitq1 two of the 2n calculi forA
n–1
and one of the two calculi forB
n
,C
n
andD
n
contain the ordinary classical differential calculus on the corresponding Lie group as a quotient. 相似文献
985.
Jürg Rätz 《Results in Mathematics》1995,27(3-4):395-401
M.C. Zdun [17] asked whether a subset S of R2 such that R × S is homeomorphic to R2 must be homeomorphic to R, all these sets being endowed with the usual topologies. We show that the answer is affirmative. 相似文献
986.
Stefan Müller-Stach 《K-Theory》1995,9(4):395-406
LetX be a smooth projective variety over an algebraically closed fieldk. We repeat Bloch's construction of aG
m
-biextension (torseur)E over CH
hom
p
(X)×CH
hom
q
(X) forp+q=dim(X)+1. First we show that in characteristic zeroE comes via pullback from the Poincaré biextension over the corresponding product of intermediate Jacobians which has been conjectured by Bloch and Murre. Then the relations betweenE and various equivalence relations for algebraic cycles are studied. In particular we reprove Murre's theorem stating that Griffiths' conjecture holds for codimension 2 cycles, i.e. every 2-codimensional cycle which is algebraically and incidence equivalent to zero has torsion Abel-Jacobi invariant. 相似文献
987.
988.
989.
990.