共查询到20条相似文献,搜索用时 46 毫秒
1.
Dr. Martin Funk 《Monatshefte für Mathematik》1982,93(1):1-14
Let
be a Minkowski-(incidence-)plane and let
be the group of free projectivities of
, i. e. the subgroup generated by pairs of proper perspectivities with identical centers. Our theorem then asserts that
is miquelian if
satisfies condition (P
5), i. e. every free projectivity with 5 fixed points is the identity. But first a lemma is shown, which holds in Möbius- and Laguerre-(incidence-)planes too: if
fulfills (P
5), then every affine derivation of
is pappian. 相似文献
2.
D.J. Daley 《Queueing Systems》2001,38(2):195-204
An equation for the distribution Z() of the duration T of the busy period in a stationary M/GI/ service system is constructed from first principles. Two scenarios are examined, being distinguished by the half-plane Re()>0 for some 00 in which the generic service time random variable S, always assumed to have a finite mean E(S), has an analytic Laplace–Stieltjes transform E(e–S
). If 0<0 then E(e–T
) is analytic in a half-plane (1,), where 01<0 and 1 is determined by the distribution of S; then
for any 0<s<|1|.When 0=0, E(e–T
) is analytic in (0,), and now more is known about T. Inequalities on the tail
() are used to show that for any 1, E(T
) is finite if and only if E(S
) is finite. It follows that the point process consisting of the starting epochs of busy periods is long range dependent if and only if E(S
2)=, in which case it has Hurst index equal to [frac12](3–), where is the moment index of S.If also the tail
(x)=Pr{Sx} of the service time distribution satisfies the subexponential density condition 0
x
(x–u)
(u)du/
(x)2E(S) as x, then
(x)/
(x)eE(S), where is the arrival rate. 相似文献
3.
D. M. Smirnov 《Algebra and Logic》2004,43(4):249-257
For integers 1 m < n, a Cantor variety with m basic n-ary operations i and n basic m-ary operations k is a variety of algebras defined by identities k(1(
), ... , m(
)) =
k and i(1(
), ... ,n(
)) = y
i, where
= (x
1., ... , x
n) and
= (y
1, ... , y
m). We prove that interpretability types of Cantor varieties form a distributive lattice, , which is dual to the direct product 1 × 2 of a lattice, 1, of positive integers respecting the natural linear ordering and a lattice, 2, of positive integers with divisibility. The lattice is an upper subsemilattice of the lattice
of all interpretability types of varieties of algebras. 相似文献
4.
D. Leladze 《Georgian Mathematical Journal》1994,1(3):287-302
We have obtained an estimate, in terms of partial and mixed moduli, of the continuity of deviation of the Cesáro (C, ) means ( = (1,...,n),i , 1 > –1,
) of the sequence of rectangular partial sums ofn-multiple (n>1) conjugate trigonometric series from then-multiple truncated conjugate function. This estimate implies the result on them
-convergence (1) of (C, ) means (1 > 0,
) provided that the essential conditions are imposed on the partial moduli of continuity. Finally, it is shown that them
-convergence cannot be replaced by ordinary convergence. 相似文献
5.
Rephael Wenger 《Discrete and Computational Geometry》1990,5(1):27-33
LetA be a family ofn pairwise disjoint compact convex sets inR
d. Let
. We show that the directed lines inR
d, d 3, can be partitioned into
sets such that any two directed lines in the same set which intersect anyAA generate the same ordering onA. The directed lines inR
2 can be partitioned into 12n such sets. This bounds the number of geometric permutations onA by 1/2
d
ford3 and by 6n ford=2. 相似文献
6.
Gerold Alsmeyer 《Mathematical Methods of Operations Research》1986,30(3):A111-A134
Let
1, 2, ... be a sequence of i.i.d. random variables with positive mean
and finite variance
and letr(b), b0, be real numbers tending to 0 asb . Definings
n=1+...+n andS
n=Sn(b)=sn+r(b)n, the stopping time =(b)=inf {n>/1:Sn >b} whereb=b(b) , will be considered with special regard to the excess over the boundaryR
b=s+r(b)–b. It turns out that the limiting distribution ofR
b is the same as in the caser(b)0 for allb. Proving this, Blackwell's renewal theorem and its integral version have to be established first in the above stated situation. Finally, an expansion ofE to vanishing terms asb will be provided and applied to some examples arising in economics.
Zusammenfassung Seien 1, 2, ... unabhängige identisch verteilte Zufallsgrößen mit positivem Erwartungswert und endlicher Varianz sowier(b), b0, reelle Zahlen mitr(b)0 für b. Sei ferners 1, s2, ... der zugehörige Summenprozeß,S n= Sn(b)=sn+r(b)n fürn1 und =(b)=inf {n1: Sn>b, wobeib=b(b) fürb . Es wird gezeigt, daß die asymptotische Verteilung des ExzessesR b=s +r(b) –b mit der im Fallr(·)0 übereinstimmt. Dazu werden sowohl das Blackwellsche Erneuerungstheorem als auch seine Integralversion in der vorher beschriebenen parameterabhängigen Situation geeignet formuliert und bewiesen. Als Folgerung ergibt sich dann eine asymptotische Entwicklung vonE(b) fürb bis zu Termen o(1). Anh- and einiger Beispiele aus dem ökonomischen Bereich wird schließlich noch aufgezeigt, wo Approximationen fürE(b) von Interesse sein können.相似文献
7.
Nikolaos S. Papageorgiou 《Analysis Mathematica》1991,17(2):141-152
8.
Zusammenfassung Es wird die Fortpflanzung elastisch-plastischer Spannungswellen in einem unendlichen Medium betrachtet, welches einer idealen Spannungs-Verformungs-Kurve folgt, Trescas Fliesskriterium unterworfen ist und einen sphärischen Hohlraum enthält, wobei an der Fläche des Hohlraumes ein Stoss
angenommen wird. Ein rechnerisches Verfahren, basiert auf endliche Differenzen, wird entwickelt and ein Beispiel gegeben.
Notation radial stress - tangential stress - K yield stress - rr non-dimensional radial stress ( /K) - non-dimensional tangential stress ( /K) - , Lame's constants - K b Bulk constant (=(3+2)/3) - v Poisson's constant - Material density - C Elastic wave velocity (=((+2)/)1/2) - C p Plastic wave velocity (=(K b /)1/2) - distance from center of cavity - r 0 cavity radius - v non-dimensional radial co-ordinate (= /r 0) - time - t non-dimensional time (=C /r 0) - radial displacement - u non-dimensional radial displacement (=/r 0) - particle velocity - v non-dimensional particle velocity (= /C) - pressure - P(t) non-dimensional pressure (= /K) 相似文献
Notation radial stress - tangential stress - K yield stress - rr non-dimensional radial stress ( /K) - non-dimensional tangential stress ( /K) - , Lame's constants - K b Bulk constant (=(3+2)/3) - v Poisson's constant - Material density - C Elastic wave velocity (=((+2)/)1/2) - C p Plastic wave velocity (=(K b /)1/2) - distance from center of cavity - r 0 cavity radius - v non-dimensional radial co-ordinate (= /r 0) - time - t non-dimensional time (=C /r 0) - radial displacement - u non-dimensional radial displacement (=/r 0) - particle velocity - v non-dimensional particle velocity (= /C) - pressure - P(t) non-dimensional pressure (= /K) 相似文献
9.
Let {\bold x}[] be a stationary Gaussian process with zero mean and spectral density f, let
be the -algebra induced by the random variables {\bold x}[], D(R1), and let
t, t > 0, be the -algebra induced by the random variables x[],supp [-t,t]. Denote by
(f) the Gaussian measure on
generated by {\bold x}. Let
t(f) be the restriction of
(f) to
t. Let f and g be nonnegative functions such that the measures
t(f) and
t(g) are absolutely continuous. Put
For a fixed g(u) and for f(u)= ft(u) close to g(u) in some sense, the asymptotic normality of
t(f,g) is proved under some regularity conditions. Bibliography: 14 titles. 相似文献
10.
Joseph Rosenblatt 《Mathematische Annalen》1977,230(3):245-272
For a mean zero norm one sequence (f
n
)L
2[0, 1], the sequence (f
n
{nx+y}) is an orthonormal sequence inL
2([0, 1]2); so if
, then
converges for a.e. (x, y)[0, 1]2 and has a maximal function inL
2([0, 1]2). But for a mean zerofL
2[0, 1], it is harder to give necessary and sufficient conditions for theL
2-norm convergence or a.e. convergence of
. Ifc
n
0 and
, then this series will not converge inL
2-norm on a denseG
subset of the mean zero functions inL
2[0, 1]. Also, there are mean zerofL[0, 1] such that
never converges and there is a mean zero continuous functionf with
a.e. However, iff is mean zero and of bounded variation or in some Lip() with 1/2<1, and if |c
n
| = 0(n
–) for >1/2, then
converges a.e. and unconditionally inL
2[0, 1]. In addition, for any mean zerof of bounded variation, the series
has its maximal function in allL
p[0, 1] with 1p<. Finally, if (f
n
)L
[0, 1] is a uniformly bounded mean zero sequence, then
is a necessary and sufficient condition for
to converge for a.e.y and a.e. (x
n
)[0, 1]. Moreover, iffL
[0, 1] is mean zero and
, then for a.e. (x
n
)[0, 1],
converges for a.e.y and in allL
p
[0, 1] with 1p<. Some of these theorems can be generalized simply to other compact groups besides [0, 1] under addition modulo one. 相似文献
11.
Gerold Wagner 《Monatshefte für Mathematik》1981,92(3):239-245
Letf be a periodic function on with period 1, piecewise continuously differentiable, satisfying
. For an arbitrary sequence = (
i
) in [0,1) put
and
. If
then
n
(f,) >c· logn holds for some positive constantc (depending onf only) and almost alln. In a certain sense the converse is also true: there is a class of functionsf with
such that
n
(f,) =o (logn).Support has been received from Netherlands Organization for the Advancement of Pure Research (Z. W. O.). 相似文献
12.
V. F. Molchanov 《Acta Appl Math》2004,81(1):191-214
For the hyperboloid of one sheet X=G/H, G=SO0(1,2), H=SO0(1,1), canonical representations R
,, C, =0,1, are defined as the restrictions to G of representations of the overgroup
=SO0(2,2) associated with a cone. They act on the torus containing two copies of X as open G-orbits. We study boundary representations generated by R
,. For some , they contain Jordan blocks. The decomposition of R
, into irreducible constituents includes a finite number (depending on ) of irreducible parts of the boundary representations. 相似文献
13.
Dr. Karl Umgeher 《Monatshefte für Mathematik》1976,81(4):311-314
We consider the set of regular functions
. We construct a Borel measure and a class of outer measures
h
onH. With these and
h
we show that: (HS)=0 and
h
(HS)=0, (S is the set of normed univalent functions). From
h
(HS)=0 follows—forh=t
—that the Hausdorff—Billingsley-dimension ofHS is zero. 相似文献
14.
Elena Prestini 《Monatshefte für Mathematik》1988,105(3):207-216
LetfL
p(
n
),n2, be a radial function and letS
Rf be the spherical partial sums operator. We prove that if
thenS
Rf(x)f(x) a.e. asR. The result is false for
and
\frac{{2n}}{{n + 1}}$$
" align="middle" border="0">
.Partially supported by M.P.I. 相似文献
15.
Alberto Marcone 《Order》2001,18(4):339-347
We pursue the fine analysis of the quasi-orderings
and
on the power set of a quasi-ordering (Q,). We set X
Y if every xX is majorized in by some yY, and X
Y if every yY is minorized in by some xX. We show that both these quasi-orderings are -wqo if and only if the original quasi-ordering is ( )-wqo. For
this holds also restricted to finite subsets, thus providing an example of a finitary operation on quasi-orderings which does not preserve wqo but preserves bqo. 相似文献
16.
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
17.
Weak L
2
-solutions u of the Schrödinger equation, –u + q(x) u – u = f(x) in L
2
, are represented by a Fourier series using spherical harmonics in order to prove the following strong maximum and anti-maximum principles in
(N 2): Let 1 denote the positive eigenfunction associated with the principal eigenvalue 1 of the Schrödinger operator
. Assume that the potential q(x) is radially symmetric and grows fast enough near infinity, and f is a `sufficiently smooth' perturbation of a radially symmetric function, f 0 and 0 f / C const a.e. in
. Then u is 1-positive for - < < 1 (i.e., u c 1 with c const > 0) and 1-negative for 1 < < 1 + (i.e., u –c1 with c const > 0), where > 0 is a number depending on f. The constant c > 0 depends on both and f. 相似文献
18.
Let < SL
n
(
) be a subgroup of finite index, where n 5. Suppose acts continuously on a manifold M, where 1(M) =
n
, preserving a measure that is positive on open sets. Further assume that the induced action on H
1(M) is non-trivial. We show there exists a finite index subgroup < and a equivariant continuous map : M
n
that induces an isomorphism on fundamental group. We prove more general results providing continuous quotients in cases where 1(M) surjects onto a finitely generated torsion free nilpotent group. We also give some new examples of manifolds with actions. 相似文献
19.
Mark C. Ho 《Integral Equations and Operator Theory》2001,41(2):179-188
Let
be the unit circle {z|z|=1} and
n
c
n
e
in
be a bounded measurable function on
. Theslant Toeplitz operator A
onL
2 (
) is defined by A
e
n
,e
m
=c
2m–n
for allm, n wheree
n
(z)=z
n
,
. In this paper, we continue the study initiated in [6] onA
*
, the adjoint ofA
. Specifically, we will show that for a certain dense set of continuous functions on
,A
*
is similar to some constant multiple of either a shift, or a shift plus a rank one operator. 相似文献
20.
V. L. Sharan 《Journal of Mathematical Sciences》2001,107(1):3601-3603
A new criterion of solvability of the interpolation problem f(
n
)=bn in the class of functions f, analytic in the right half-plane
and such that there exists c
1(0;+) such that |f(z)|c
1exp((c1|z|)) for all z
, where is a positive increasing continuous differentiable function on [0;+), for which (t)+ as t+ and there exists c
2(0;+) such that
for all t 1 is described. 相似文献