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1.
Korn-type inequalities for thin periodic structures of period and width h() with h() 0 are presented. Periodic meshes, three-dimensional road structures, and three-dimensional box structures are considered. A particular attention is paid to structures with the so-called critical width when
0$$
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. 相似文献
2.
Hans-Joachim Samaga 《Journal of Geometry》1984,22(2):183-188
By using a computer the following theorem is proved: Consider K=GF(q), q {32,64,81,128}, :K2 K2 bijective such that
P,Q K2. Then is a semi-isometry. The assumption bijective can be dropped if q {32,128}. 相似文献
3.
Gikō Ikegami 《Inventiones Mathematicae》1989,95(2):215-246
Summary We define a constraint system
, [0,0), which is a kind of family of vector fields
on a manifold. This is a generalized version of the family of the equations
, [0,0),x
m
,y
n
. Finally, we prove a singular perturbation theorem for the system
, [0,0).Dedicated to Professor Kenichi Shiraiwa on his 60th birthday 相似文献
4.
Stefan Müller 《Calculus of Variations and Partial Differential Equations》1993,1(2):169-204
Summary Minimizers of functionals like
subject to periodic (or Dirichlet) boundary conditions are investigated. While for =0 the infimum is not attained it is shown that for sufficiently small > 0, all minimizers are periodic with period 1/3. Connections with solid-solid phase transformations are indicated. 相似文献
5.
A. S. Zinov'ev 《Mathematical Notes》1972,12(5):743-746
We obtain sufficient conditions for the absolute convergence of Fourier series for functions of L
d
2
depending on the properties of the function being expanded and the rate of growth of the sums
of the system of functions {k(t)} orthonormalized in [a, b] with respect to d(t). We show that if at some point x [a, b] the function (t) has a discontinuity, at that point the Fourier series of any functionf(t) L
d
2
, converges absolutely.Translated from Matematicheskie Zametki, Vol. 12, No. 5, pp. 511–516, November, 1972. 相似文献
6.
Victor Kaftal 《Integral Equations and Operator Theory》1982,5(1):50-70
LetA be a von Neumann algebra,J be the ideal of compact operators relative toA and letF
+ be the left-Fredholm class ofA. We call almost left-Fredholm the class
= {A A: if P A is a projection and AP J then P J}. Then
and the inclusion is proper unlessA is semifinite and has a non-large center.
satisfies all of the algebraic properties ofF
+ but it is generally not open. IfA is semifinite then A
iff there are central projectionsG
with G = I such that AG F+(AG). Let :A A/J. Then the left almost essential spectrum ofA A,
, coincides with the set of eigenvalues of (A) 相似文献
7.
Epsilon efficiency 总被引:1,自引:0,他引:1
D. J. White 《Journal of Optimization Theory and Applications》1986,49(2):319-337
This paper considers the extension of -optimality for scalar problems to vector maximization problems, or efficiency problems, which havem objective functions defined on a set
.It is shown that the natural extension of the scalar -optimality concepts [viz, given >0, given a solution setS, ifxS there exists an efficient solutiony with f(x)–f(y), and given an efficient solutiony, there exists anxS with f(x)–f(y)] do not hold for some methods used. Six concepts of -efficient sets are introduced and examined, to a very limited extent, in the context of five methods used for generating efficient points or near efficient points.In doing so, a distinction is drawn between methods in which the surrogate optimizations are carried out exactly, and those where terminal -optimal solutions are obtained.The author would like to thank the referees whose thoroughness was extremely helpful for the revised paper. 相似文献
8.
Many global optimization problems can be formulated in the form min{c(x, y): x X, y Y, (x, y) Z, y G} where X, Y are polytopes in
p
,
n
, respectively, Z is a closed convex set in p+n, while G is the complement of an open convex set in
n
. The function c:
p+n
is assumed to be linear. Using the fact that the nonconvex constraints depend only upon they-variables, we modify and combine basic global optimization techniques such that some new decomposition methods result which involve global optimization procedures only in
n
. Computational experiments show that the resulting algorithms work well for problems with smalln. 相似文献
9.
10.
Let
for anyf H(R), where
(x): =
–1(x–1). Then (x) P
(x + h) for some h R and > 0; P denotes the Poisson kernel.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova Akademii Nauk SSSR, Vol. 170, pp. 82–89, 1989. 相似文献
11.
L. C. G. Rogers 《Probability Theory and Related Fields》1987,76(3):291-298
Summary Given a Brownian motionB, we consider the filtration (
x
xR
), where
x
is defined as the -field generated by the excursions ofB belowx. In this paper we prove a conjecture of Walsh which says that all -martingales are continuous. 相似文献
12.
M. F. Horodnii 《Ukrainian Mathematical Journal》2003,55(7):1071-1085
For a sectorial operator A with spectrum (A) that acts in a complex Banach space B, we prove that the condition (A) i
R = Ø is sufficient for the differential equation
where is a small positive parameter, to have a unique bounded solution x
for an arbitrary bounded function f: R B that satisfies a certain Hölder condition. We also establish that bounded solutions of these equations converge uniformly on R as 0+ to the unique bounded solution of the differential equation x(t) = Ax(t) + f(t). 相似文献
13.
We prove the existence of continuously differentiable solutions with required asymptotic properties as t +0 and determine the number of solutions of the following Cauchy problem for a functional differential equation:
where : (0, ) (0, +), g: (0, ) (0, +), and h: (0, ) (0, +) are continuous functions, 0 < g(t) t, 0 < h(t) t, t (0, ),
, and the function is continuous in a certain domain. 相似文献
14.
Chihiro Suetake 《Geometriae Dedicata》1994,51(2):123-131
Let be a translation plane of orderq
3,q an odd prime power, whose kern GF(q). Letl
be the line at infinity of . LetG be a solvable collineation group of in the linear translation complement, which acts transitively onl
, and letH be a maximal normal cyclic subgroup ofG. Then the restriction
ofH onl
acts semiregularly onl
and
{1, 2, 3, 6}, where
is the restriction ofG onl
(ifq –1(mod 3), then
{1, 2}). Ifq {3, 5} and
{1, 2}, then is determined completely, using a computer. 相似文献
15.
R. Schäfke 《Journal of Mathematical Sciences》2004,124(6):5364-5389
First, in joint work with S. Bodine of the University of Puget Sound, Tacoma, Washington, USA, we consider the second-order differential equation 2 y'=(1+2 (x, ))y with a small parameter , where is analytic and even with respect to . It is well known that it has two formal solutions of the form y±(x,)=e±x/h±(x,), where h±(x,) is a formal series in powers of whose coefficients are functions of x. It has been shown that one (resp. both) of these solutions are 1-summable in certain directions if satisfies certain conditions, in particular concerning its x-domain. We show that these conditions are essentially necessary for 1-summability of one (resp. both) of the above formal solutions. In the proof, we solve a certain inverse problem: constructing a differential equation corresponding to a certain Stokes phenomenon. The second part of the paper presents joint work with Augustin Fruchard of the University of La Rochelle, France, concerning inverse problems for the general (analytic) linear equations
r
y' = A(x,) y in the neighborhood of a nonturning point and for second-order (analytic) equations y' - 2xy'-g(x,) y=0 exhibiting resonance in the sense of Ackerberg-O'Malley, i.e., satisfying the Matkowsky condition: there exists a nontrivial formal solution
such that the coefficients have no poles at x=0. 相似文献
16.
V. Koubek 《Algebra Universalis》1996,35(2):296-331
Given distinct varieties
and
of the same type, we say that
is relatively
-universal if there exists an embedding :K
from a universal categoryK such that for every pairA, B ofK-objects, a homomorphismf:A B has the formf=g for someK-morphismg:A B if and only if Im(f)
. Finitely generated relatively
-universal varieties of Heyting algebras are described for the variety
of Boolean algebras, the variety generated by a three element chain, and for the variety generated by the four element Boolean algebra with an added greatest element.Dedicated to the memory of Alan DayPresented by J. Sichler.The support of the NSERC is gratefully acknowledged. 相似文献
17.
S. Sivaganesan 《Annals of the Institute of Statistical Mathematics》1993,45(1):187-199
Range of the posterior probability of an interval over the -contamination class ={=(1–)0+q:qQ} is derived. Here, 0 is the elicited prior which is assumed unimodal, is the amount of uncertainty in 0, andQ is the set of all probability densitiesq for which =(1–)0+q is unimodal with the same mode as that of 0. We show that the sup (resp. inf) of the posterior probability of an interval is attained by a prior which is equal to (1–)0 except in one interval (resp. two disjoint intervals) where it is constant. 相似文献
18.
Proper holomorphic mappings between generalized pseudoellipsoids 总被引:3,自引:0,他引:3
Gilberto Dini Angela Selvaggi Primicerio 《Annali di Matematica Pura ed Applicata》1991,158(1):219-229
Summary We characterize the existence of proper holomorphic mappings between pseudoellipsoids of the form
. If f:()() is any such mapping, the existence of a subgroup of Aut (()) such that
is shown equivalent to a condition on the branch locus of f. 相似文献
19.
Hansmartin Zeuner 《Journal of Theoretical Probability》1994,7(2):225-245
Let (X
n:n) be i.i.d. with finite variance and values in a hypergroupK:=+ or and
j=1
n
X
j
be the randomized sum of these random variables. It is shown that the processes
converge in distribution to a Gaussian process in the caseK=+, that the processes
converge towards a Bessel process on + in the case of polynomial growth of the hypergroupK=+ or , and that in the case of exponential growth
converges towards a Brownian motion asn. 相似文献
20.
Denote by
the class of all triangle-free
graphs on n vertices and
m edges. Our main result is
the following sharp threshold, which answers the question for
which densities a typical triangle-free graph is bipartite. Fix
> 0 and let
. If
n/2 m (1 – ) t
3, then almost
all graphs in
are not bipartite, whereas if
m (1 + )t
3, then almost
all of them are bipartite. For m (1 + )t
3, this allows
us to determine asymptotically the number of graphs in
. We also obtain corresponding
results for C
-free graphs, for any
cycle C
of fixed odd length.
Forschergruppe Algorithmen, Struktur, Zufall
supported by Deutsche Forschungsgemeinschaft grant FOR
413/1-1 相似文献