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91.
本文把转移概率流向图和转移概率母函数的方法引入到对MIL-STD-1916中连续抽样方案的讨论中,给出了抽样方案的平均检出质量函数AOQ,抽查特性函数L(p)和平均检查比率函数AFI全部3项指标的理论推导,为进一步探讨带有停止检查的MIL-STD-1916中连续抽样方案及相应的动态检出质量提供了理论基础。 相似文献
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Hong Li Yushu Liu Shaowu Zhang 《International Journal of Infrared and Millimeter Waves》2000,21(5):837-844
Soliton propagation in fiber with randomly varying birefringence is studied by using self-companying operator method. It is shown that randomly varying birefringence leads to time jitters increasing with transmission distance, and disrupts the stability of soliton transmission. The fluctuation of time jitters is stochastic, and nonlinear gain is introduced to remove the influence. 相似文献
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97.
Hybrid harmony search algorithm and fuzzy mechanism for solving congestion management problem in an electricity market 下载免费PDF全文
A hybrid technique for solving the congestion management problem in an electricity market based on harmony search algorithm (HAS) and Fuzzy mechanism is presented in this article. This algorithm does not require initial value setting for the variables and does not require differential gradients, thus it can consider discontinuous functions as well as continuous functions. The HAS is a recently developed powerful evolutionary algorithm, inspired by the improvisation process of musicians, for solving single/multiobjective optimization problems. In the proposed technique, each musician plays a note for finding a best harmony all together. Transmission pricing and congestion management are the key elements of a competitive electricity market based on direct access. They also focus of much of the debate concerning alternative approaches to the market design and the implementation of a common carrier electricity system. This article focuses on the tradeoffs between simplicity and economic efficiency in meeting the objectives of a transmission pricing and congestion management scheme. The effectiveness of the proposed technique is applied on 30 and 118 bus IEEE standard power system in comparison with CPSO, PSO‐TVAC, and PSO‐TVIW. The numerical results demonstrate that the proposed technique is better and superior than other compared methods. © 2015 Wiley Periodicals, Inc. Complexity 21: 90–98, 2016 相似文献
98.
F. Hoppensteadt H. Salehi A. Skorokhod 《Journal of Dynamics and Differential Equations》1997,9(3):463-505
Let (X, ) and (Y,C) be two measurable spaces withX being a linear space. A system is determined by two functionsf(X): X X and:X×YX, a (small) positive parameter and a homogeneous Markov chain {y
n
} in (Y,C) which describes random perturbations. States of the system, say {x
n
X, n=0, 1,}, are determined by the iteration relations:x
n+1
=f(x
n
)+(x
n
,Yn+1) forn0, wherex
0
=x
0 is given. Here we study the asymptotic behavior of the solutionx
n
as 0 andn under various assumptions on the data. General results are applied to some problems in epidemics, genetics and demographics.Supported in part by NSF Grant DMS92-06677.Supported in part by NSF Grant DMS93-12255. 相似文献
99.
Vladimir Egorov Alexey Tatarinov Noune Sarvazyan Randee Wood Leonid Magidenko Shreyasee Amin Sundeep Khosla Richard J. Ruh Jennifer M. Ruh Armen Sarvazyan 《Ultrasonics》2014
The objective of this study was to evaluate if the Bone UltraSonic Scanner (BUSS) can detect osteoporosis in postmenopausal women. BUSS is an axial transmission multi-frequency ultrasonometer for acquisition of wave propagation profiles along the proximal anterior tibia. We derived 10 diagnostically significant BUSS parameters that were then compared with the DXA spine T-score, which was used in this study as the “gold standard” for the assessment of osteoporosis (T-score <−2.5). BUSS wave parameters were studied in 331 postmenopausal women examined by 9 trained operators at 3 clinical sites with use of 3 devices. The efficiency of each BUSS parameter in osteoporosis detection was assessed using a receiver operating characteristic curve analysis. Area under the curve (AUC) for each of 10 parameters ranged from 58.1% to 70.2%. Using these parameters a linear classifier was derived which provided at its output 83.0% AUC, 87.7% sensitivity and 63.2% specificity to DXA-identified osteoporosis. The results of this study confirm BUSS’s capability to detect osteoporosis in postmenopausal women. 相似文献
100.
本文结合分位数回归技术,基于删失回归模型,把Claeskens和Hjort的传统兴趣信息准侧(focused information criterion,FIC)扩展到兴趣向量的情形,提出扩展的兴趣信息准则(extended focused information criterion,E-FIC),有效解决了同时针对多个兴趣参数的平均估计问题,并且对删失响应变量的不同水平分位数进行建模,以全面反映响应变量分布特征,有效克服异常值和厚尾模型误差的影响.基于扩展的兴趣信息准则给出参数的平均估计方法,证明估计的渐近性质.通过Monte Carlo随机模拟试验比较所提估计方法和最小二乘方法在有限样本量下的表现,用所提方法对原发性胆汁性肝硬化数据集进行数据分析. 相似文献