共查询到20条相似文献,搜索用时 31 毫秒
1.
Edgar R. Lorch 《Integral Equations and Operator Theory》1981,4(3):422-434
The objects studied are the subalgebras of
which contain co. These are isometrically isomorphic to the algebras C(
) where
is a compactification of a discrete denumerable set N . It is shown: 1) If
is metric then there is a projection of norm 1, P: C(
) C(
) with kernel co defined by PF = f o where is a retraction of
onto
=
– N . 2) If
is metric, then the group of homeomorphisms of
is isomorphic to a complete group of permutations of the natural numbers . 3) The group of homeomorphisms of a compact metric space is the homomorphic image of a complete group of permutations of ("complete" means "no outer automorphisms, trivial center"). 相似文献
2.
Vratislava Mošová 《Applications of Mathematics》2000,45(6):401-410
As a measure of deformation we can take the difference D
- R, where D
is the deformation gradient of the mapping
and R is the deformation gradient of the mapping
, which represents some proper rigid motion. In this article, the norm
is estimated by means of the scalar measure e(
) of nonlinear strain. First, the estimates are given for a deformation
W
1,p() satisfying the condition . Then we deduce the estimate in the case that
(x) is a bi-Lipschitzian deformation and . 相似文献
3.
Pavel Krejčí 《Applications of Mathematics》2000,45(6):439-468
This paper deals with the asymptotic behavior as t of solutions u to the forced Preisach oscillator equation
where
is a Preisach hysteresis operator, L
(0, ) is a given function and t 0 is the time variable. We establish an explicit asymptotic relation between the Preisach measure and the function (or, in a more physical terminology, a balance condition between the hysteresis dissipation and the external forcing) which guarantees that every solution remains bounded for all times. Examples show that this condition is qualitatively optimal. Moreover, if the Preisach measure does not identically vanish in any neighbourhood of the origin in the Preisach half-plane and
, then every bounded solution also asymptotically vanishes as t . 相似文献
4.
In this paper, we consider equations of the form
, where
is a function with values in the Hilbert space
, the operator B is symmetric, and the operator A is uniformly positive and self-adjoint in
. The linear operator
generating the C
0-semigroup in the energy space
is associated with this equation. We prove that this semigroup is exponentially stable if the operator B is uniformly positive and the operator A dominates B in the sense of quadratic forms. 相似文献
5.
Michel Matthey 《K-Theory》2001,24(1):87-107
Let be a group, F the free
-module on the set of finite order elements in , with acting by conjugation, and
the ring extension of
by % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeaacaGaaiaabeqaamaabaabaaGcbaWaaiWaaeaada% WcaaqaaiaaigdaaeaatCvAUfKttLearyGqLXgBG0evaGqbciab-5ga% UbaaieaacaGFLbGaaGOmaiaabc8acqWFPbqAcaqGVaGae8NBa42aaq% qaaeaacqGHdicjcqaHZoWzcqGHiiIZcqqHtoWrcaqGGaGaae4Baiaa% bAgacaqGGaGaae4BaiaabkhacaqGKbGaaeyzaiaabkhacaqGGaGae8% NBa4gacaGLhWoaaiaawUhacaGL9baaaaa!563E!\[\left\{ {\frac{1}{n}e2{\text{\pi }}i{\text{/}}n\left| {\exists \gamma \in \Gamma {\text{ of order }}n} \right.} \right\}\]. For a ring R with
, we build an injective assembly map
, detected by the Dennis trace map. This is proved by establishing a delocalization property for the assembly map
in Hochschild homology, namely providing a gluing of simpler assembly maps (i.e. localized at the identity of ) to build
, and by delocalizing a known assembly map in K-theory to define
. We also prove the delocalization property in cyclic homology and in related theories. 相似文献
6.
Wenpeng Zhang 《Acta Mathematica Hungarica》1998,78(4):345-357
Let p be an odd prime. For each integer a with x < a x + u and (a,p) = 1, we define by a 1 (mod p) and 1 p - 1. Let r(p,u,x) be the number of integers with x < a x + u and (a,p) = 1 for which a and are of opposite parity, and let E(n,u,x) = r(n,u,x) - 1/2
1, where
denotes summation over all a such that (a,p) = 1. The main purpose of this paper is to prove that for any positive integer 1 u
we have the asymptotic formula
. 相似文献
7.
A. Cabot 《Journal of Optimization Theory and Applications》2004,120(2):275-303
Let H be a real Hilbert space and let
be a
function that we wish to minimize. For any potential
and any control function
which tends to zero as t+, we study the asymptotic behavior of the trajectories of the following dissipative system:
The (S) system can be viewed as a classical heavy ball with friction equation (Refs. 1–2) plus the control term (t)U(x(t)). If is convex and (t) tends to zero fast enough, each trajectory of (S) converges weakly to some element of argmin . This is a generalization of the Alvarez theorem (Ref. 1). On the other hand, assuming that is a slow control and that and U are convex, the (S) trajectories tend to minimize U over argmin when t+. This asymptotic selection property generalizes a result due to Attouch and Czarnecki (Ref. 3) in the case where U(x)=|x|2/2. A large part of our results are stated for the following wider class of systems:
where
is a C
1 function. 相似文献
{\text{0}}{\text{.}}$$ " align="middle" vspace="20%" border="0"> |
8.
Gikō Ikegami 《Inventiones Mathematicae》1989,95(2):215-246
Summary We define a constraint system
, [0,0), which is a kind of family of vector fields
on a manifold. This is a generalized version of the family of the equations
, [0,0),x
m
,y
n
. Finally, we prove a singular perturbation theorem for the system
, [0,0).Dedicated to Professor Kenichi Shiraiwa on his 60th birthday 相似文献
9.
A. M. Protopopov 《Algebra and Logic》2003,42(4):279-286
We study into the question of whether a partial order can be induced from a partially right-ordered group
onto a space
of right cosets of
w.r.t. some subgroup
of
. Examples are constructed showing that the condition of being convex for
in
is insufficient for this. A necessary and sufficient condition (in terms of a subgroup
and a positive cone
of
) is specified under which an order of
can be induced onto
. Sufficient conditions are also given. We establish properties of the class of partially right-ordered groups
for which
is partially ordered for every convex subgroup
, and properties of the class of groups such that
is partially ordered for every partial right order
on
and every subgroup
that is convex under
. 相似文献
10.
Let G be a connected graph. For at distance 2, we define , and , if then . G is quasi-claw-free if it satisfies , and G is P
3-dominated() if it satisfies , for every pair (x, y) of vertices at distance 2. Certainly contains as a subclass. In this paper, we prove that the circumference of a 2-connected P
3-dominated graph G on n vertices is at least min or , moreover if then G is hamiltonian or , where is a class of 2-connected nonhamiltonian graphs. 相似文献
11.
Manuel del Pino Michal Kowalczyk Monica Musso 《Calculus of Variations and Partial Differential Equations》2005,24(1):47-81
We consider the boundary value problem
in a bounded, smooth domain
in
with homogeneous Dirichlet boundary conditions. Here
0,k(x)
$$
" align="middle" border="0">
is a non-negative, not identically zero function. We find conditions under which there exists a solution
which blows up at exactly m points as
and satisfies
. In particular, we find that if
,
0
$" align="middle" border="0">
and
is not simply connected then such a solution exists for any given
Received: 11 February 2004, Accepted: 17 August 2004, Published online: 22 December 2004 相似文献
12.
Günter Mayer 《Applications of Mathematics》1998,43(4):241-254
For contractive interval functions [g] we show that
results from the iterative process
after finitely many iterations if one uses the epsilon-inflated vector
as input for [g] instead of the original output vector [x]
k
. Applying Brouwer's fixed point theorem, zeros of various mathematical problems can be verified in this way. 相似文献
13.
We introduce the notion of hyper-self-duality for Bose-Mesner algebras as a strengthening of formal self-duality. Let
denote a Bose-Mesner algebra on a finite nonempty set X. Fix p X, and let
and
denote respectively the dual Bose-Mesner algebra and the Terwilliger algebra of
with respect to p. By a hyper-duality of
, we mean an automorphism of
such that
for all
; and
is a duality of
.
is said to be hyper-self-dual whenever there exists a hyper-duality of
. We say that
is strongly hyper-self-dual whenever there exists a hyper-duality of
which can be expressed as conjugation by an invertible element of
. We show that Bose-Mesner algebras which support a spin model are strongly hyper-self-dual, and we characterize strong hyper-self-duality via the module structure of the associated Terwilliger algebra. 相似文献
14.
Niels Jakob Laustsen 《K-Theory》2001,23(2):115-127
We prove that the K-groups of the Banach algebra
of bounded, linear operators on the pth James space
, where 1 < p < , are given by
and
. Moreover, for each Banach space
and each non-zero, closed ideal
contained in the ideal of inessential operators, we show that
and
. This enables us to calculate the K-groups of
for each Banach space
which is a direct sum of finitely many James spaces and
-spaces. 相似文献
15.
Hiroshi Suzuki 《Journal of Algebraic Combinatorics》1998,7(2):165-180
It is well known that imprimitive P-polynomial association schemes
with
are either bipartite or antipodal, i.e., intersection numbers satisfy either
for all
for all
. In this paper, we show that imprimitive
-polynomial association schemes
with
are either dual bipartite or dual antipodal, i.e., dual intersection numbers satisfy either
. 相似文献
16.
Rudolf Scharlau 《Geometriae Dedicata》1987,24(1):77-84
Following earlier work of Tits [8], this paper deals with the structure of buildings which are not necessarily thick; that is, possessing panels (faces of codimension 1) which are contained in two chambers, only. To every building , there is canonically associated a thick building
whose Weyl group W(
) can be considered as a reflection subgroup of the Weyl group W() of . One can reconstruct from
together with the embedding W(
) W(). Conversely, if
is any thick building and W any reflection group containing W(
) as a reflection subgroup, there exists a weak building with Weyl group W and associated thick building
. 相似文献
17.
Ján Jakubík 《Czechoslovak Mathematical Journal》2003,53(3):641-653
In this paper we deal with the (, )-distributivity of an MV-algebra
, where and are nonzero cardinals. It is proved that if
is singular and (, 2)-distributive, then it is (, )-distributive. We show that if
is complete then it can be represented as a direct product of MV-algebras which are homogeneous with respect to higher degrees of distributivity. 相似文献
18.
Matthew R. Brown 《Journal of Algebraic Combinatorics》2002,15(2):107-125
If a GQ S of order (s, s) is contained in a GQ S of order (s, s
2) as a subquadrangle, then for each point X of S\S the set of points
of S collinear with X form an ovoid of S. Thas and Payne proved that if S=
(4,q),q even, and
is an elliptic quadric for each XS\S,thenS
(5,q). In this paper we provide a single proof for the q odd and q even cases by establishing a link between the geometry involved and the first cohomology group of a related simplicial complex. 相似文献
19.
A. Cossidente J. W. P. Hirschfeld G. Korchmáros F. Torres 《Compositio Mathematica》2000,121(2):163-181
The number N of rational points on an algebraic curve of genus g over a finite field
satisfies the Hasse–Weil bound
. A curve that attains this bound is called maximal. With
and
, it is known that maximalcurves have
. Maximal curves with
have been characterized up to isomorphism. A natural genus to be studied is
and for this genus there are two non-isomorphic maximal curves known when
. Here, a maximal curve with genus g
2 and a non-singular plane model is characterized as a Fermat curve of degree
. 相似文献
20.
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