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911.
F. Paul Wyman William M. Orr Jr. 《The Journal of the Operational Research Society》1973,24(4):593-601
This paper develops a near optimal policy for opening a second counter in a quick-service restaurant when n persons are in the first line, given that the arrival process is cyclic rather than purely stationary. A simulation was written in GPSS which permitted the use of different arrival generators during different time segments of the simulated day. Results indicate that as n is varied, waiting time and utilization levels exhibit an S-shaped curve between the pure 1 facility and the 2 facility cases. Results also indicate that a cyclic arrival process greatly increases (relative to the case of exponential arrivals) mean waiting time, facility utilization, and the range of n. Finding the optimal (least cost) value of n is illustrated for cases in which costs of customer waiting time can be meaningfully imputed. 相似文献
912.
913.
Moshe Kaveh 《Waves in Random and Complex Media》1991,1(3):S121-S128
A review is presented of some new and exciting phenomena regarding the multiple scattering of optical waves in random systems. In particular, the author develops the important role played by the vector nature of the wave on memory effects (the 'polarization memory effect'), correlations and statistical fluctuations ('microstatistics'). He also describes the recent progress on the effect of a restricted geometry on correlation phenomena and nonRayleigh statistics. 相似文献
915.
Yossi Moshe 《Journal d'Analyse Mathématique》2006,99(1):267-294
Let λ be the upper Lyapunov exponent corresponding to a product of i.i.d. randomm×m matrices (X
i)
i
0/∞
over ℂ. Assume that theX
i's are chosen from a finite set {D
0,D
1...,D
t-1(ℂ), withP(X
i=Dj)>0, and that the monoid generated byD
0, D1,…, Dq−1 contains a matrix of rank 1. We obtain an explicit formula for λ as a sum of a convergent series. We also consider the case
where theX
i's are chosen according to a Markov process and thus generalize a result of Lima and Rahibe [22].
Our results on λ enable us to provide an approximation for the numberN
≠0(F(x)n,r) of nonzero coefficients inF(x)
n.(modr), whereF(x) ∈ ℤ[x] andr≥2. We prove the existence of and supply a formula for a constant α (<1) such thatN
≠0(F(x)n,r) ≈n
α for “almost” everyn.
Supported in part by FWF Project P16004-N05 相似文献
916.
Moshe Schwartz 《Physics letters. A》1985,107(5):199-203
A new approach to quenched random problems, based on constructing an equivalent annealed system, is presented. The difficulties with the existing solutions of the random field problem are discussed. The new approach is applied to the random field problem yielding a different new result for the dimensionality shift. A by-product of this result is that the lower critical dimension is 2 for the Ising model. 相似文献
917.
918.
Moshe Rosenfeld 《Israel Journal of Mathematics》1975,21(1):24-30
A study is made of the non-regular planar 3-connected graphs with constant weight. 相似文献
919.
920.
Pavol Hell Moshe Rosenfeld 《Journal of Algorithms in Cognition, Informatics and Logic》1983,4(4):303-309
Given a tournament with n vertices, we consider the number of comparisons needed, in the worst case, to find a permutation υ1υ2…υn of the vertices, such that the results of the games υ1υ2, υ2υ3,…, υn−1υn match a prescribed pattern. If the pattern requires all arcs to go forwrd, i.e., υ1 → υ2, υ2 → υ3,…, υn−1 → υn, and the tournament is transitive, then this is essentially the problem of sorting a linearly ordered set. It is well known that the number of comparisons required in this case is at least cn lg n, and we make the observation that O(n lg n) comparisons suffice to find such a path in any (not necessarily transitive) tournament. On the other hand, the pattern requiring the arcs to alternate backward-forward-backward, etc., admits an algorithm for which O(n) comparisons always suffice. Our main result is the somewhat surprising fact that for various other patterns the complexity (number of comparisons) of finding paths matching the pattern can be cn lgαn for any α between 0 and 1. Thus there is a veritable spectrum of complexities, depending on the prescribed pattern of the desired path. Similar problems on complexities of algorithms for finding Hamiltonian cycles in graphs and directed graphs have been considered by various authors, [2, pp. 142, 148, 149; 4]. 相似文献