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951.
L.L. Helms 《Stochastic Processes and their Applications》1984,17(1):101-114
Simultaneous changes of time scales of the components of a vector Markov process are defined and developed. Measurability properties, Dynkin's lemma, and the strong Markov property are established for the transformed process. 相似文献
952.
LICHANGPIN YANGZHONGHUA 《高校应用数学学报(英文版)》1998,13(3):263-270
This paper deals with the steady state bifurcation of the K-S equation in two spatial dimensions with periodic boundary value condition and of zero mean. With the increase of parameter a, the steady state bifurcation behaviour can be very complicated. For convenience, only the cases a=2 and a=5 witl be discussed. The asymptotic expressions of the steady state solutions bifurcated from the trivial solution near a=2 and a=5 are given. And the stability of thenontriviat sotutions bifurcated from a=2 is studied. Of course, the cases a=n^2 m^2,n,m∈N(a≠2,5) can be similarly discussed by the same method which is used to discussing the cases a=2 and a= 5. 相似文献
953.
H. Strauss 《Numerische Mathematik》1984,44(3):337-347
Summary This paper deals with quadrature formulae of Gauss type corresponding to subspaces of spline functionsS
m–1, k
of degreem–1 withk fixed knots. We shall show monotonicity of the quadrature formulae for functions which are contained in the so-called convexity cone ofS
m–1,k
Moreover, we apply these results to monosplines and establish comparison theorems for these splines. 相似文献
954.
On the hellinger square integral with respect to an operator valued measure and stationary processes
Andrzej Makagon 《Journal of multivariate analysis》1984,14(1):114-133
A construction of the Hellinger square integral with respect to a semispectral measure in a Banach space B is given. It is proved that the space of values of a B-valued stationary stochastic process is unitarily isomorphic to the space of all B1-valued measures that are Hellinger square integrable with respect to the spectral measure of the process. Some applications of the above theorem in the prediction theory (especially to interpolation problem) are also considered. 相似文献
955.
Simeon M. Berman 《Annals of the Institute of Statistical Mathematics》1984,36(1):301-321
Summary Let {X
n,j,−∞<j<∞∼,n≧1, be a sequence of stationary sequences on some probability space, with nonnegative random variables. Under appropriate
mixing conditions, it is shown thatS
n=Xn,1+…+X
n,n has a limiting distribution of a general infinitely divisible form. The result is applied to sequences of functions {f
n(x)∼ defined on a stationary sequence {X
j∼, whereX
n.f=fn(Xj). The results are illustrated by applications to Gaussian processes, Markov processes and some autoregressive processes of
a general type.
This paper represents results obtained at the Courant Institute of Mathematical Sciences, New York University, under the sponsorship
of the National Sciences Foundation, Grant MCS 82-01119. 相似文献
956.
Everett W. Howe 《Mathematische Annalen》1996,305(1):387-392
957.
958.
J. M. Peña 《BIT Numerical Mathematics》1997,37(4):910-924
A matrixA issign-regular if, for each orderk, allk×k submatrices ofA have determinant with the same sign. In this paper, a pivoting strategy ofO(n) operations for the Gaussian elimination of linear systems whose coefficient matrices are sign-regular is proposed. Backward
error analysis of this pivoting strategy is performed and small error bounds are obtained. Our results can also be applied
to linear systems whose coefficient matrices have sign-regular inverses. 相似文献
959.
Philip S. Marcus 《Aequationes Mathematicae》1977,15(2-3):169-171
Cumulative transition density functions of stationary Markov chains are shown to sausfy the Menger triangle inequality under thet-normT = Prod. 相似文献
960.
A continuous function f from a continuum X onto a continuum Y is quasi-monotone if, for every subcontinuum M of Y with nonvoid interior, f-1(M) has a finite number of components each of which is mapped onto M by f. A θn-continuum is one that no subcontinuum separates into more than n components. It is known that if f is quasi-monotone and X is a θ1-continuum, then Y is a θ1-continuum or a θ2-continuum that is irreducible between two points. Examples are given to show that this cannot be generalized to a θn-continuum and n + 1 points for any n >1, but it is proved that if f is quasi-monotone and X is a θn-continuum, then Y is a θn-continuum or a θn+1-continuum that is the union of n + 2 continua H,S1,S2,…,Sn+1, whe for each i, Si is the closure of a component of Y H, Si is irreducible from some point Pi to H, and H is irreducible about its boundary. Some theorems and examples are given concerning the preservation of decomposition elements by a quasi-monotone map defined on a θn-continuum that admits a monotone, upper-semicontinuous decomposition onto a finite graph. 相似文献