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51.
Peixia Gao Sabine Wittevrongel Joris Walraevens Herwig Bruneel 《Mathematical Methods of Operations Research》2008,67(2):269-284
In this paper, we study the behavior of a discrete-time multiserver buffer system with infinite buffer size. Packets arrive
at the system according to a two-state Markovian arrival process. The service times of the packets are assumed to be constant,
equal to multiple slots. The behavior of the system is analyzed by means of an analytical technique based on probability generating
functions (PGF’s). Explicit expressions are obtained for the PGF’s of the system contents and the packet delay. From these,
the mean values, the variances and the tail distributions of the system contents and the packet delay are calculated. Numerical
examples are given to show the influence of various model parameters on the system behavior. 相似文献
52.
Prof. Dr. B. F. Arnold 《Mathematical Methods of Operations Research》1990,34(1):59-74
Summary In controlling the mean of a multivariate normally distributed quality characteristic the main disadvantage of the globalT
2-control charts is that they don't indicate the component of the quality characteristic which gives rise to an alarm. To avoid this disadvantage the joint use of¯x-charts is proposed in this paper, where — for the sake of simplicity — the investigations are restricted to the case of independent components and to one-sided¯x-charts. On the basis of an economic objective function an approximation to the optimal design of the¯x-charts procedure is derived and discussed. It turns out that at least in the bivariate case the nearly optimal economic design is very close to the exact solution.Supported by the Deutsche Forschungsgemeinschaft (DFG). 相似文献
53.
针对非合作大目标的被动测距问题,介绍了一种基于单目图像序列和成像方向的测距系统,并进行了性能分析.这种测距系统的特点是无需初始距离导引,它对目标距离的估计借助于专门的定位方程,方程由目标特征线度、摄像机的空间坐标、目标在采样时刻对相机的方位角和俯仰角决定.其中,方位角和俯仰角通过光电经纬仪获得,摄像机的空间坐标通过GPS获得,目标特征线度通过相邻帧图像匹配得到.分析表明,该系统的性能主要取决于特征线度的准确度,其他测量误差如目标的方位角、俯仰角和摄像机的空间坐标对其影响较小.目标特征线度选取时,在相邻帧目标图像匹配点中,筛选出三个具有较大极限的尺度不变特征变换关键点,构造三角形及其外接圆,在外接圆上取经过三角形重心且平行或垂直于尺度不变特征变换主方向的弦线作为特征线度,这种特征线度对目标旋转不敏感.实验结果表明这种测距方法能够实现对非合作大目标的被动测距. 相似文献
54.
In order to improve the precision of quasi-dimensional combustion model for predicting diesel engine performance and promote the real time operating performance of the simulation model, a new phase-divided spray mixing model is proposed and the quasi-dimensional combustion model of diesel engine working process is developed. The software MATLAB/Simulink is utilized to build the quasi-dimensional combustion model of diesel engine working process, and the performance for diesel engine is simulated. The simulation results agree with experimental data quite well. The comparisons between them show that the relative error of power and brake specific fuel consumption is less than 2.8% and the relative error of nitric oxide and soot emissions is less than 9.1%. By utilization of this simulation model with personal computer, the average computational time for one diesel engine working process is 36 s, which presents good real time operating performance of the model. At the same time, the influence of parameters in calculation of air entrainment on prediction precision of diesel engine’s simulation model is analyzed. 相似文献
55.
NONLINEAR EXPECTATIONS AND NONLINEAR MARKOV CHAINS 总被引:2,自引:1,他引:2
PENG Shige 《数学年刊B辑(英文版)》2005,26(2):159-184
§1.IntroductionLet(?,F)be a measurable space and let Lb(F)be the space of F-measurable andbounded real functions.A nonlinear expectation is a continuous functionalE[·]:Lb(F)?→Rthat is order preserving(i.e.,E[X1]≥E[X2],if X1≥X2)and constant preserving 相似文献
56.
Although several analytical models have been proposed in the literature for binary n-cubes with deterministic routing, most of them have not included the effects of virtual channel multiplexing on network performance. The only mathematical model for deterministic wormhole routing in hypercubes with virtual channels was proposed in [Y. Boura, Design and Analysis of Routing Schemes and Routers for Wormhole-routed Mesh Architectures, Ph.D. Thesis, Department of Computer Science and Engineering, Pennsylvania State University, 1995] which uses complex combinatorial analysis with a computation time of O(N=2n) for an n-dimensional hypercube. This paper proposes a new and simple analytical model to compute message latency in binary n-cubes with virtual channels. It is very simple and easy to understand which uses an average case analysis and requires a computation time of O(n) for an n-dimensional hypercube. Results from simulation experiments confirm that the proposed model exhibits a good degree of accuracy for various network sizes and under different operating conditions. 相似文献
57.
58.
Choquet积分的收敛定理 总被引:2,自引:2,他引:0
Murofushi、Sugeno等学者已对关于模糊测度的Choquet积分进行了详细的研究,但关于积分的收敛理论是不够的。本文讨论这一问题,给出Choquet积分的一些收敛定理,包括广义单调收敛定理、Fatou引理等。从中可以看出,Choquet积分与Sugeno模糊积分具有相同的收敛定理。 相似文献
59.
蓖麻毒蛋白的提取及分析 总被引:7,自引:0,他引:7
本文报道了蓖麻毒蛋白的提取和分析,采用琼脂糖(Sepharose 4B)分离和纯化,研究了高效液相色谱法同时测定蓖麻毒蛋白和蓖麻碱,结果 令人满意。 相似文献
60.