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61.
We investigate the tail behavior of the sojourn-time distribution for a request of a given length in an M/G/1 Processor-Sharing
(PS) queue. An exponential asymptote is proven for general service times in two special cases: when the traffic load is sufficiently
high and when the request length is sufficiently small. Furthermore, using the branching process technique we derive exact
asymptotics of exponential type for the sojourn time in the M/M/1 queue. We obtain an equation for the asymptotic decay rate
and an exact expression for the asymptotic constant. The decay rate is studied in detail and is compared to other service
disciplines. Finally, using numerical methods, we investigate the accuracy of the exponential asymptote.
AMS 2000 Subject Classifications Primary:60K25,Secondary: 60F10,68M20,90B22 相似文献
62.
We present a modified optimal control scheme based on the Krotov method, which allows for strict limitations on the spectrum of the optimized laser fields. A frequency constraint is introduced and derived mathematically correct, without losing monotonic convergence of the algorithm. The method guarantees a close link to learning loop control experiments and is demonstrated for the challenging control of nonresonant Raman transitions, which are used to implement a set of global quantum gates for molecular vibrational qubits. 相似文献
63.
This study presents a method of adaptive identification of parameters describing Sugeno fuzzy inference system in presence of bounded disturbances while maintaining the readability and interpretability of the fuzzy model during and after identification. This method do not require any a priori knowledge of a bound on the disturbance and noise and of a bound on the unknown parameters values. The method can be used for the robust and adaptive identification of slowly time varying nonlinear systems using fuzzy inference systems. The suggested method was used to build a fuzzy expert system that approximates the functional relationship between physical fitness and some of the measurable physiological parameters by their real measurements and opinion (human-experiences) of a medical expert. 相似文献
64.
Test examples for nonlinear programming codes 总被引:3,自引:0,他引:3
The increasing importance of nonlinear programming software requires an enlarged set of test examples. The purpose of this note is to point out how an interested mathematical programmer could obtain computer programs of more than 120 constrained nonlinear programming problems which have been used in the past to test and compare optimization codes. 相似文献
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68.
We introduce a regularized equilibrium problem in Banach spaces, involving generalized Bregman functions. For this regularized problem, we establish the existence and uniqueness of solutions. These regularizations yield a proximal-like method for solving equilibrium problems in Banach spaces. We prove that the proximal sequence is an asymptotically solving sequence when the dual space is uniformly convex. Moreover, we prove that all weak accumulation points are solutions if the equilibrium function is lower semicontinuous in its first variable. We prove, under additional assumptions, that the proximal sequence converges weakly to a solution. 相似文献
69.
Cavalcanti ED Maciel FM Villeneuve P Lago RC Machado OL Freire DM 《Applied biochemistry and biotechnology》2007,137(1-12):57-65
The influence of several factors on the hydrolytic activity of lipase, present in the acetone powder from dormant castor seeds (Ricinus communis) was evaluated. The enzyme showed a marked specificity for short-chain substrates. The best reaction conditions were an acid medium, Triton X-100 as the emulsifying agent and a temperature of 30 degrees C. The lipase activity of the acetone powder of different castor oil genotypes showed great variability and storage stability of up to 90%. The toxicology analysis of the acetone powder from genotype Nordestina BRS 149 showed a higher ricin (toxic component) content, a lower 2S albumin (allergenic compound) content, and similar allergenic potential compared with untreated seeds. 相似文献
70.
Regina Benveniste 《The Journal of the Operational Research Society》1985,36(5):433-450
This paper discusses methods for the solution of the combined zoning and location problem for several emergency units. This is a stochastic optimization problem. The stochastic aspects include ordered preference of servers. A constraint of equal workload for the servers is also dealt with. Non-linear programming techniques are adapted for its solution. 相似文献