共查询到20条相似文献,搜索用时 31 毫秒
1.
Shigeyoshi Owa 《Georgian Mathematical Journal》1995,2(5):535-545
Two integral operatorsP
andQ
for analytic functions in the open unit disk are introduced. The object of the present paper is to derive some properties of integral operatorsP
andQ
. 相似文献
2.
Wim Caspers 《Potential Analysis》1992,1(4):401-409
Perturbations of -+/|x| (with >0) by a point interaction centered at zero are defined in L
p(3). This is done for 3/2
0 (3{0}), such that the extension is the negative generator of an analytic semigroup on L p(3). 相似文献
3.
Lian-Xi Ku 《Southeast Asian Bulletin of Mathematics》2000,24(3):375-382
In this note, we prove that, for Robins boundary value problem, a unique solution exists if fx(t, x, x), fx(t, x, x), (t), and (t) are continuous, and fx -(t), fx -(t), 4(t) 2 + 2(t) ++ 2(t), and 4(t) 2 + 2(t) + 2(t).AMS Subject Classification (2000) 34B15 相似文献
4.
Hiroshi Suzuki 《Graphs and Combinatorics》1991,7(4):363-375
Let be a distance regular graph with diameterd, and
d
() the set of vertices at distanced from. is said to be thin if the induced subgraph on
d
() is a union of cliques for every vertex. We show that the diameterd is bounded above by a function depending only onk
d, which is the cardinality of
d
(), if is not thin. We also investigate thin distance regular graphs witha
d 0. 相似文献
5.
Živorad Tomovski 《Analysis Mathematica》2003,29(2):165-170
In this paper equivalent classes of the classes M'
and S'
p
r, p >1, 0,r {0,1,2,...,[]} defined by Sheng [5] are obtained. Then it is shown that the classes of Fourier coefficients S
p, S'
p(case r==0) and S
p(), p>1, defined by . V. Stanojevi, V. B. Stanojevi Sheng and the author of the present note are identical. As a corollary of this result, the L
1-estimate for cosine series, obtained in [10], is refined. 相似文献
6.
A. V. Bukhvalov 《Journal of Mathematical Sciences》1978,9(2):129-137
In this paper we obtain necessary and sufficient conditions in order that a linear operator, acting in spaces of measurable functions, should admit an integral representation. We give here the fundamental results. Let (Ti,
i) (i=1,2) be spaces of finite measure, and let (T,) be the product of these spaces. Let E be an ideal in the space S(T1,
1) of measurable functions (i.e., from |e1||e2|, e1 S (T1,
1), e2E it follows that e1E). THEOREM 2. Let U be a linear operator from E into S(T2,
2). The following statements are equivalent: 1) there exists a-measurable kernel K(t,S) such that (Ue)(S)=K(t,S) e(t)d(t) (eE); 2) if 0enE (n=1,2,...) and en0 in measure, then (Uen)(S) 0
2 a.e. THEOREM 3. Assume that the function (t,S) is such that for any eE and for s a.e., the
2-measurable function Y(S)=(t,S)e(t)d
1(t) is defined. Then there exists a-measurable function K(t,S) such that for any eE we have (t,S)e(t)d
1(t)=K(t,S)e(t)d
1(t)
1a.e.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 47, pp. 5–14, 1974. 相似文献
7.
Ikuyo Kaneko 《Mathematical Programming》1977,12(1):48-59
The parametric linear complementarity problem is given by the conditions:q + p + Mz 0, 0,z 0,z
T
(q + p + Mz) = 0. Under the assumption thatM is a P-matrix, Cottle proved that the solution mapz() of the above problem is montonically nondecreasing in the parameter for every nonnegativeq and everyp if and only ifM is a Minkowski matrix. This paper examines whether a similar result holds in various other settings including a nonlinear case. 相似文献
8.
Janet Heine Barnett 《Periodica Mathematica Hungarica》1995,30(3):171-176
It is consistent that 1(1,(:n))2 holds in any random extension for n finite and countable. 相似文献
9.
Dr. Johannes Schoißengeier 《Monatshefte für Mathematik》1979,87(1):21-52
In this paper we give the connection between the zeros of the -function and sequences(g(p)), p prime, mod 1 ifg(x)=x
for 0, >0 or ifg(X) is a polynomial in . 相似文献
10.
We consider the boundary-value problem u
tt + u
t + (1 + cos2)sin u =2
u
xx, u
x|x=0=ux|x==0, where 0<1, =(1+)t, ,> 0, and the sign of is arbitrary. It is proved that for an appropriate choice of the external parameters and and for sufficiently small the number of exponentially stable solutions 2-periodic in can be made equal to an arbitrary predefined number. 相似文献
11.
This paper deals with the following Dirichlet problem Lu = 1A ( Au – qu = – f ( , u ) on ] 0, [ , u, ( 0 ) = 0, u ( ) = 0, where ] 0, + ], q 0 is continuous on [ 0, [ × ] 0, + [ ] 0, + [ is continuous and A satisfies some appropriate conditions. The main result is the existence and the uniqueness of a strictly positive regular solution of the problem ( ). Moreover, we study the behaviour of this solution in a neighbourhood of . Our approach is based on the use of the Green's function of the homogeneous equation and Schauder's fixed point theorem. 相似文献
12.
Yves Deniel 《Journal of Theoretical Probability》1989,2(4):475-485
We give a new direct proof of the a.s. convergence of the Cesàro- means of a stationary process (X
n) when 0<<1 andE(X
n
p
)<+ with p>1 and we show that this result does not hold in general for p=1. We also consider similar questions for orthogonal random variables. Finally, we study the a.s. convergence of Riesz harmonic means. 相似文献
13.
S. A. Shcherbakov 《Journal of Mathematical Sciences》1990,48(1):103-107
We consider a two-dimensional Hadamard manifoldM (i.e., a complete simply connected smooth Riemannian manifold of nonpositive Gaussian curvature). It is proved thatM satisfies the visibility axiom (for any>0 and each pointpM there exists a numberr=r(p, ) such that any geodesic whose distance fromp is at leastr subtends an angle less than or equal to from the pointp), if for any asymptotic geodesics and the inequality inf {d((t),(s))}=0 holds, whered is the Riemannian metric ofM.Translated from Ukrainskií Geometricheskií Sbornik, Issue 28, 1985, pp. 126–132. 相似文献
14.
Andrea Laforgia Martin E. Muldoon 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1988,39(2):267-271
Summary We show, among other things, that the positive zeros of a solution ofy
+x
y=0,y(0)=0 decrease to 1 as increases, 0.
To the memory of Milo Háik
This research was supported by grants from the Natural Sciences and Engineering Research Council (Canada) and Consiglio Nazionale delle Ricerche (Italy). Some of the work was done while the second-named author was visiting the Department of Mathematics, University of Torino. 相似文献
Sommario Si dimostra, tra l'altro, che gli zeri positivi d'una soiuzione diy +x y=0,y(0)=0 decrescono al limite 1, quando cresce, 0.
To the memory of Milo Háik
This research was supported by grants from the Natural Sciences and Engineering Research Council (Canada) and Consiglio Nazionale delle Ricerche (Italy). Some of the work was done while the second-named author was visiting the Department of Mathematics, University of Torino. 相似文献
15.
Scott W. Weeks Graham C. Sander Ian G. Lisle Jean-Yves Parlange 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1994,45(6):841-853
When both the diffusivityD and fractional flow functionf have a power law dependence on the water content , i.e.D=D
o andf=+1, the nonlinear transport equation for radially symmetric two phase flow can, in certain circumstances, be reduced to a weakly coupled system of two first order nonlinear ordinary differential equations. Numerical solutions of these equations for a constant flux boundary conditionV
wo and comparison with experimental data are given. In particular, when the fluxV
wo and a are related byV
wo( + 1)/D
o=2, a new fully explicit analytical solution is found as (r, t)=(1 – r
2/4D
ot)1/ forr
2 < 4D
ot/ and (r, t)=0 forr
2 4D
ot/ We show that the existence of this exact soution is due to the presence of a Lagrangian symmetry. 相似文献
16.
Ralph Kummetz 《Journal of Geometry》1999,66(1-2):136-143
We show that a pointwise convergent sequence (
n)
nN of continuous collineations of a compact projective plane converges uniformly if and only if the pointwise limit of (
n)
nN has a quadrangle in its image. Moreover is then a continuous collineation. Furthermore, we derive that a homomorphism between topological projective planes is continuous if and only if it is continuous at some point.Supported by DFG/Graduiertenkolleg. 相似文献
17.
We introduce two new local 1-indices of the same type as the Bourgain 1-index; the +1-index and the +1-weakly null index. We show that the +1-weakly null index of a Banach space X is the same as the Szlenk index of X, provided X does not contain 1. The +1-weakly null index has the same form as the Bourgain 1-index: if it is countable it must take values for some <1. The different 1-indices are closely related and so knowing the Szlenk index of a Banach space helps us calculate its 1-index, via the +1-weakly null index. We show that I(C())=^1++1. 相似文献
18.
Muhammad El-Taha 《Queueing Systems》1996,22(1-2):47-63
An input-output processZ = {Z(t), t 0} is said to be-rate stable ifZ(t) = o((t)) for some non-negative function(t). We prove that the processZ is -rate stable under weak conditions that include the assumption that input satisfies a linear burstiness condition and Z is asymptotically average stable. In many cases of interest, the conditions for-rate-stability can be verified from input data. For example, using input information, we establish-rate stability of the workload for multiserver queues, an ATM multiplexer, and-rate stability of queue-length processes for infinite server queues. 相似文献
19.
J. A. Geurst A. J. N. Vreenegoor 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1988,39(3):376-386
It is shown that nonlinear void-fraction waves constitute exact solutions of the two-fluid equations for bubbly flow, if and only if the virtual-mass coefficientm() is a definite function of the void fraction. In the case of spherical bubbles the functional dependence is given bym()=(1/2)(1–a)(1–3). A similar expression was obtained recently by means of an elaborate linear stability analysis of a uniform two-phase flow. It is remarkable that the greater part of the physical quantities of a nonlinear void-fraction wave depends linearly on. The virtual-mass coefficient may be derived directly from a special form of Hamilton's variational principle.
Zusammenfassung Es wird gezeigt daß nichtlineare Konzentrationswellen exakte Lösungen der Zweifluiden Gleichungen einer Blasenströmung darstellen dann und nur dann, wenn der Koeffizientm() der virtuellen Masse eine bestimmte Funktion der Volumenkonzentration der Blasen ist. Die funktionelle Abhängigkeit ist im Falle kugelförmiger Blasen gegeben durchm()= (1/2)(1–) (1–3). Ein gleicher Ausdruck wurde neulich mittels einer umständlichen linearen Stabilitätsanalysis einer uniformen Zweiphasen-Strömung erhalten. Es ist bemerkenswert daß der größere Teil der physikalischen Größen einer nichtlinearen Konzentrationswelle in linearer Weise von abhängt. Der Koeffizient der virtuellen Masse kann in direkter Weise von einer speziellen Form des Hamiltonschen Variationsprinzips hergeleitet werden.相似文献
20.
The authors consider the nonlinear difference equation xn+1=xn+xn-kf(xn-k),n=0,1,(0.1) where (0,1), k 0,1, and f C1[[0,), [0,)] with f(x) < 0.They give sufficient conditions for the unique positive equilibrium of (0.1) to be a global attractor of all positive solutions. The results here are somewhat easier to apply than those of other authors. An application to a model of blood cell production is given. 相似文献