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101.
The set of all group relaxations of an integer program contains certain special members called Gomory relaxations. A family
of integer programs with a fixed coefficient matrix and cost vector but varying right hand sides is a Gomory family if every
program in the family can be solved by one of its Gomory relaxations. In this paper, we characterize Gomory families. Every
TDI system gives a Gomory family, and we construct Gomory families from matrices whose columns form a Hilbert basis for the
cone they generate. The existence of Gomory families is related to the Hilbert covering problems that arose from the conjectures
of Seb?. Connections to commutative algebra are outlined at the end.
Received: May 17, 2001 / Accepted: February 7, 2002
Published online: April 24, 2003
RID="⋆"
ID="⋆" Research partially supported by NSF grant DMS-0100141. 相似文献
102.
In this paper, we investigate the exact distribution of the waiting time for ther-th ℓ-overlapping occurrence of success-runs of a specified length in a sequence of two state Markov dependent trials. The
probability generating functions are derived explicitly, and as asymptotic results, relationships of a negative binomial distribution
of orderk and an extended Poisson distribution of orderk are discussed. We provide further insights into the run-related problems from the viewpoint of the ℓ-overlapping enumeration
scheme. We also study the exact distribution of the number of ℓ-overlapping occurrences of success-runs in a fixed number
of trials and derive the probability generating functions. The present work extends several properties of distributions of
orderk and leads us a new type of geneses of the discrete distributions. 相似文献
103.
Asger Hobolth Jan Pedersen Eva B. Vedel Jensen 《Annals of the Institute of Statistical Mathematics》2003,55(2):227-242
In this paper we propose a flexible continuous parametric shape model for star-shaped planar objects. The model is based on
a polar Fourier expansion of the normalized radius-vector function. The expected phase amplitudes are modelled by a simple
regression with parameters having nice geometric interpretations. The suggestedgeneralized p-order model is an extension of first- and second-order Gaussian shape models, and in particular the Gaussian assumption is relaxed. The
statistical analysis is straightforward, as demonstrated by an application concerning shape discrimination of two cell nuclei
populations. 相似文献
104.
105.
106.
Some improvements and generalizations of Finks results about Hadamards inequality for log-concave functions are given.AMS Subject Classification: 26D07, 26D15, 26A51. 相似文献
107.
Xu Cheng 《Mathematische Annalen》2003,325(2):229-248
Let M be a 2m-dimensional compact Riemannian manifold with Anosov geodesic flow. We prove that every closed bounded k form, k≥2, on the universal covering of M is d(bounded). Further, if M is homotopy equivalent to a compact K?hler manifold, then its Euler number χ(M) satisfies (−1)
m
χ(M)>0.
Received: 25 September 2001 / Published Online: 16 October 2002 相似文献
108.
We study the metrical theory of fibred systems, in particular, in the case of continued fraction mixing systems. We get the
limit distribution of the largest value of a continued fraction mixing stationary stochastic process with infinite expectation
and some related results. These are analogous to J. Galambos, W. Philipp, and H. G. Diamond–J. D. Vaaler theorems for the
regular continued fractions. As an application, we see that these theorems hold for Jacobi-Perron algorithm.
Received September 30, 2001; in revised form January 8, 2002 相似文献
109.
This article is devoted to the study of the Cauchy problem in Gevrey classes for some higher order weakly hyperbolic equations
with time-dependent coefficients and without lower order terms. 相似文献
110.
Su-Yun Huang Chuhsing Kate Hsiao Ching-Wei Chang 《Annals of the Institute of Statistical Mathematics》2003,55(3):655-670
The article provides a refinement for the volume-corrected Laplace-Metropolis estimator of the marginal likelihood of DiCiccioet al. The correction volume of probability α in DiCiccioet al. is fixed and suggested to take the value α=0.05. In this article α is selected based on an asymptotic analysis to minimize
the mean square relative error (MSRE). This optimal choice of α is shown to be invariant under linear transformations. The
invariance property leads to easy implementation for multivariate problems. An implementation procedure is provided for practical
use. A simulation study and a real data example are presented. 相似文献