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131.
In this paper, we consider the stochastic fluid-flow model of a single node in a high-speed telecommunication network handling multi-class traffic. The node has multiple buffers, one for each class of traffic. The contents of these buffers are multiplexed onto a single output channel using one of the service scheduling policies: the Timed Round Robin Policy or the Static Priority Service Policy. The Quality of Service requirements for each class are based on cell loss probabilities. Using effective bandwidth methodologies and the recently developed bounds for semi-Markov modulated traffic, we solve call admission control problems for the two service scheduling policies at this node. We compare the performance of the effective bandwidth methodologies and the SMP bounds technique. We also numerically compare the performance of the two service scheduling policies. 相似文献
132.
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134.
H. B. Zhu H. X. Ge L. Y. Dong S. Q. Dai 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(1):103-108
Based on the Nagel-Schreckenberg (NaSch)
model of traffic flow, a modified cellular automaton (CA) traffic
model with the density-dependent randomization (abbreviated as the
DDR model) is proposed to simulate traffic flow. The fundamental
diagram obtained by simulation shows the ability of this modified
NaSch model to capture the essential features of traffic flow,
e.g., synchronized flow, metastable state, hysteresis and phase
separation at higher densities. Comparisons are made between this
DDR model and the NaSch model, also between this DDR model and the
VDR model. And the underlying mechanism is analyzed. All these
results indicate that the presented model is reasonable and more
realistic. 相似文献
135.
A. Vairo 《The European Physical Journal A - Hadrons and Nuclei》2007,31(4):728-733
I review recent progress in heavy-quarkonium physics from an effective-field theory perspective. In this unifying framework,
I discuss advances in perturbative calculations for low-lying quarkonium observables and in lattice calculations for high-lying
ones, and progress and lasting puzzles in quarkonium production. 相似文献
136.
137.
This paper develops the basic analytical theory related to some recently introduced crowd dynamics models.Where well posedness was known only locally in time,it is here extended to all of R+.The result... 相似文献
138.
Bin Tang Chunfeng Wu Jiacheng Li Youyu Fan Hefang Hu Long Zhang 《Journal of Non》2009,355(37-42):2006-2009
Windows for infrared sensors on missiles, aircraft and high energy laser systems must be of excellent spectral properties, high optical quality, large and durable enough to protect delicate sensors from harsh operating conditions. This paper describes work being done for IR window applications on heavy metal oxyfluoride (HMOF) glasses, which provide a combination of infrared transparency, strength, hardness, and environmental stability in a largely-sized formable material, and represents potential candidate materials for infrared windows. 相似文献
139.
The directed flow of protons is studied in the quark-gluon string model as a function of the impact parameter for S+S and Pb+Pb reactions at 160 AGeV/c. A significant reduction of the directed flow in midrapidity range, which can lead to the development of the antiflow, is found due to the absorption of early emitted particles by massive spectators (shadowing effect). This effect can mimic the formation of the quark-gluon plasma (QGP). However, in the absorption scenario the antiflow is stronger for the system of light colliding nuclei than for the heavy ones, while in the case of the plasma creation the effect should be opposite. 相似文献
140.
固定需求下基于概率型随机平衡的交通网络设计模型及算法 总被引:2,自引:0,他引:2
罗文昌 《宁波大学学报(理工版)》2008,21(2):221-224
在考虑网络中用户的路径选择行为满足概率型随机平衡的条件下,给出了交通网络设计的双层规划模型,同时设计了基于差分的启发式求解算法. 相似文献