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91.
A novel method is proposed that reduces the bit error rate (BER) in an optically amplified system by using a Mach–Zender interferometer coherence manipulation at the receiver. Exact analysis is presented, which shows that the signal-to-noise ratio can be improved by 3 dB. Resulting BER improvements are presented. 相似文献
92.
This paper presents floating potential and current measurements due to oil-flow electrification inside a multilayer sensor incorporated in a closed loop filled with fresh transformer oil. All leakage currents at the sensor inlet and outlet, the capacitive current and the streaming current are measured. The waveforms of these currents, floating potential as well as the oil temperature at the sensor inlet are simultaneously recorded for laminar flow and at controlled operating conditions. The measured floating potentials are compared with the calculated ones under different oil-flow velocities and good agreement has been found. 相似文献
93.
94.
Chen Chen 《Physica A》2007
In this paper, we first discuss the origin of preferential attachment. Then we establish the generalized preferential attachment (GPA) which has two new properties; first, it encapsulates both the topological and weight aspects of a network, which makes it is neither entirely degree preferential nor entirely weight preferential. Second, it can tell us not only the chance that each already-existing vertex being connected but also how much weight each new edge has. The GPA can generate four power-law distributions, besides the three for vertex degrees, vertex strengths, and edge weights, it yields a new power-law distribution for the subgraph degrees. 相似文献
95.
The distribution of patients’ lengths of stay in English hospitals is measured by using routinely collected data from 11 years. It is found to be well approximated by a power law distribution spanning over more than three decades. To explain this observation, a theoretical resource allocation model is presented. It is based on iterative long-term scheduling of hospital beds, and its main assumption is that future beds are allocated preferentially. This represents a situation where different parts of the health care system compete for resources, with bargaining powers proportional to current resource levels. 相似文献
96.
本文简要介绍了7×35cm~2多灯丝大面积源的供电保护系统,给出了该系统的基本设计思想,电源简化原理图及主要电路特点和已达到的技术指标。 相似文献
97.
本文给出一组托卡马克堆芯等离子体功率平衡方程,它描述了在非自持和非麦氏分布情况下等离子体功率平衡的问题,计算结果表明。在现实可行的聚变堆工程和相应的等离子体参数情况下,堆芯中每秒可产生聚变中子PN大于10~19。 相似文献
98.
Nariaki Sugiura Hidetoshi Murakami Seong Keon Lee Yasutomo Maeda 《Annals of the Institute of Statistical Mathematics》2006,58(1):93-100
This paper answers the long-standing question of whether the two-sided Wilcoxon rank test for equal sample sizes is unbiased
against a location parameter family of distributions by giving a counterexample. It is also shown that the nonrandomized two-sided
Wilcoxon test for equal sample sizes with the least positive significance level is unbiased. 相似文献
99.
On the Effect of Misspecifying the Density Ratio Model 总被引:1,自引:0,他引:1
Konstantinos Fokianos Irene Kaimi 《Annals of the Institute of Statistical Mathematics》2006,58(3):475-497
The density ratio model specifies that the log-likelihood ratio of two unknown densities is of known linear form which depends
on some finite dimensional parameters. The model can be broadened to allow for m-samples in a quite natural way. Estimation of both parametric and nonparametric part of the model is carried out by the method
of empirical likelihood. However the assumed linear form has an impact on the estimation and testing for the parametric part.
The goal of this study is to quantify the effect of choosing an incorrect linear form and its impact to inference. The issue
of misspecification is addressed by embedding the unknown linear form to some parametric transformation family which yields
ultimately to its identification. Simulated examples and data analysis integrate the presentation. 相似文献
100.
Kenneth S. Berenhaut John D. Foley 《Journal of Mathematical Analysis and Applications》2006,322(2):1159-1167
This note employs path counting techniques to extend recent results on bounds for odd order linear recurrences to higher dimensions. The results imply optimal zero-free polydisks for multivariable power series with 0, 1 coefficients. Among the applications is a result that states that the optimal zero-free polydisk has radius approximately 1/(v+1), for large dimensions v. 相似文献