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111.
112.
Consider a network where two routes are available for users wishing to travel from a source to a destination. On one route (which could be viewed as private transport) service slows as traffic increases. On the other (which could be viewed as public transport) the service frequency increases with demand. The Downs-Thomson paradox occurs when improvements in service produce an overall decline in performance as user equilibria adjust. Using the model proposed by Calvert [10], with a ⋅|M|1 queue corresponding to the private transport route, and a bulk-service infinite server queue modelling the public transport route, we give a complete analysis of this system in the setting of probabilistic routing. We obtain the user equilibria (which are not always unique), and determine their stability.AMS subject classification: 60K30, 90B15, 90B20, 91A10, 91A13This revised version was published online in June 2005 with corrected coverdate 相似文献
113.
K. Rerbal I. Solomon J.-N. Chazalviel F. Ozanam 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,51(1):61-64
We have investigated the temperature dependence of
photoluminescence in hydrogenated amorphous silicon-carbon alloys
a-Si1-xCx:H prepared by glow discharge in the low-power regime.
The radiative recombination process, due to photocarriers trapped on
band-edge states, is in competition with the thermal escape of the
photocarriers into the mobility bands. The model gives a quantitative fit
with experiment, without any adjustable parameter, provided the width of the
band-edge distribution of states is taken as the width of the conduction
band only (measured by “photo-induced infra-red spectroscopy”) and not as
the Urbach energy, as it is usually assumed. 相似文献
114.
The use of numerical models has greatly increased our understanding of the electrical and microphysical process within electrified clouds. We use the University of Washington, 1.5-dimensional thunderstorm model to examine the effects of including a runaway electron based lightning initiation mechanism. We find that this mechanism can significantly alter the electrification history of modeled storms and produce vertical electric field profiles that are very similar to those of observed storms. To cite this article: R. Solomon et al., C. R. Physique 3 (2002) 1325–1333. 相似文献
115.
P. Blasiak A. Gawron A. Horzela K. A. Penson A. I. Solomon 《Czechoslovak Journal of Physics》2005,55(11):1335-1341
We present a combinatorial method of constructing solutions to the normal ordering of boson operators. Generalizations of
standard combinatorial notions — the Stirling and Bell numbers, Bell polynomials and Dobinski relations — lead to calculational
tools, which allow to find explicitly normally ordered forms for a large class of operator functions.
Presented at the International Colloquium “Integrable Systems and Quantum Symmetries”, Prague, 16–18 June 2005. 相似文献
116.
P. Blasiak A. Gawron A. Horzela K. A. Penson A. I. Solomon 《Czechoslovak Journal of Physics》2006,56(10-11):1093-1098
We introduce a generalization of the Dobiński relation, through which we define a family of Bell-type numbers and polynomials. Such generalized Dobiński relations are coherent state matrix elements of expressions involving boson ladder operators. This may be used in order to obtain normally ordered forms of polynomials in creation and annihilation operators, both if the latter satisfy canonical and deformed commutation relations. 相似文献
117.
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119.
E I Solomon D M Dooley R H Wang H B Gray M Credonio F Mogno G L Romani 《Journal of the American Chemical Society》1976,98(4):1029-1031
120.