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51.
We derive fast recursions to compute the probability that k or more consecutive customer losses take place during a busy period of a queue, the so called k-CCL probability, for regular and oscillating M
X
/G/1/n systems. 相似文献
52.
Ze-shui Xu 《佛山科学技术学院》2009,1(1):79-89
An intuitionistic preference relation is a powerful means to express decision makers’information of intuitionistic preference
over criteria in the process of multi-criteria decision making. In this paper, we first define the concept of its consistence
and give the equivalent interval fuzzy preference relation of it. Then we develop a method for estimating criteria weights
from it, and then extend the method to accommodate group decision making based on them And finally, we use some numerical
examples to illustrate the feasibility and validity of the developed method. 相似文献
53.
Bennis and O’Toole [Bennis, W.G., O’Toole, J., 2005. How business schools lost their way. Harvard Business Review 83, 96–104] have recently argued that decision makers need guidance in ‘making decisions in the absence of clear facts’. As such, decision makers must be able to resourcefully use whatever limited information is available and advantageously portray its implications. Based on recently published theory which directly addresses this requirement, this paper demonstrates, through a practical example, how decision makers can make systemic decisions in situations characterized by extremely limited information and, furthermore, what form such decisions can take. Evidence is provided, therefore, that operational research can effectively address what appears to be a gap in management training. 相似文献
54.
The effects of dilatational phase transformation on the target strength of ceramic materials are investigated based on Tate's
model. The constitutive behavior of materials in different regions (elastic, cracked, plastic and phase transformation) are
taken into account. It is found that, with a proper choice of material parameters, the dilatational phase transformation can
increase effectively the target strengthR. This would be of importance in penetration-resistance design.
This work is partially supported by the Excellent Youth Foundation of Harbin Institute of Technology 相似文献
55.
We establish NP-completeness of two problems on core stable coalitions in hedonic games. In the first problem every player has only two acceptable coalitions in his preference list, and in the second problem the preference structures arise from the distances in an underlying metric space. 相似文献
56.
Diffusion of monatomic guest species within confined media has been understood to a good degree due to investigations carried
out during the past decade and a half. Most guest species that are of industrial relevance are actually polyatomics such as,
for example, hydrocarbons in zeolites. We attempt to investigate the influence of non-spherical nature of guest species on
diffusion. Recent molecular dynamics (MD) simulations of motion of methane in NaCaA and NaY, benzene in NaY and one-dimensional
channels AlPO4−5, VPI−5 and carbon nanotube indicate interesting insights into the influence of the host on rotational degrees of freedom
and orientational properties. It is shown that benzene in one-dimensional channels where the levitation parameter is near
unity exhibits translational motion opposite to what is expected on the basis of molecular anisotropy. Rotational motion of
benzene also possesses rotational diffusivities aroundC
6
and C2axes opposite to what is expected on the basis of molecular geometry. Methane shows orientational preference for 2+ 2 or 1
+ 3 depending on the magnitude of the levitation parameter. 相似文献
57.
Computing the minimal covering set 总被引:1,自引:0,他引:1
We present the first polynomial-time algorithm for computing the minimal covering set of a (weak) tournament. The algorithm draws upon a linear programming formulation of a subset of the minimal covering set known as the essential set. On the other hand, we show that no efficient algorithm exists for two variants of the minimal covering set–the minimal upward covering set and the minimal downward covering set–unless P equals NP. Finally, we observe a strong relationship between von Neumann–Morgenstern stable sets and upward covering on the one hand, and the Banks set and downward covering on the other. 相似文献
58.
59.
S. Minkevičius 《Acta Appl Math》2008,104(3):271-285
The model of an open queueing network in heavy traffic has been developed. These models are mathematical models of computer
networks in heavy traffic. A limit theorem has been presented for the virtual waiting time of a customer in heavy traffic
in open queueing networks. Finally, we present an application of the theorem—a reliability model from computer network practice. 相似文献
60.
Yousef Hashem Zahran 《国际流体数值方法杂志》2008,57(6):745-760
We describe a hybrid method for the solution of hyperbolic conservation laws. A third‐order total variation diminishing (TVD) finite difference scheme is conjugated with a random choice method (RCM) in a grid‐based adaptive way. An efficient multi‐resolution technique is used to detect the high gradient regions of the numerical solution in order to capture the shock with RCM while the smooth regions are computed with the more efficient TVD scheme. The hybrid scheme captures correctly the discontinuities of the solution and saves CPU time. Numerical experiments with one‐ and two‐dimensional problems are presented. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献