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Risk Decision Analysis of Logistics Purchasing Based on mathematical expectation

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Open Journal of Modelling and Simulation 2016年第2期4卷 41-45页

作者： Fengying Wang Zhixin Liang School of Information Beijing Wuzi University Beijing China

The mathematical expectation value method is a commonly used method in risk decision-making. This paper studies the problem of how to arrange the purchase plan in order to get the maximum expected profit;considering the applicable principles of mathematical expectation, the decision method for getting the optimal decision scheme is given. Finally, we do simulation and stability analysis on an example and obtain the reasonable result. This result shows that mathematical expectation value method is effective in solving the problem of risk decision.

关键词： mathematical expectation Logistics Purchasing Risk Decision Stability

Research on data classification method based on class attribute mathematical expectation

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Research on data classification method based on class attrib...

作者： ZhaoLi Wang Hetian Department of Elementary Courses Chifeng Industry Vocational Technology College

In order to solve the problem of complex data in large data era,the classification method of spatial data based on mathematical expectation theory of category attributes is improved and *** optimizing the arithmetic of mathematical expectation function of data attributes,the mapping value of discrete attributes can be obtained,the mapping value features can be mined and the spatial dimension can be classified,and the mathematical expectation attributes of data can be used as parameter coordinates to determine the classification of data,and the spatial distance of data can be calculated according to the *** attributes are used to plan the spatial scope of data classification,so as to finish the accurate classification of data ***,the experiment proves that the classification method is real and effective,and the accuracy is obviously improved compared with the traditional classification method.

关键词： Class attribute mathematical expectation data classification

The mathematical expectation of GDOP and Its Application

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The Mathematical Expectation of GDOP and Its Application

第四届中国卫星导航学术年会

作者： Tao HAN Haitao WU Xiaochun LU Juan DU Xiaozhen ZHANG National Time Service Center Chinese Academy of Sciences Key Laboratory of Precision Navigation and Timing Technology Graduate University of the Chinese Academy of Sciences Academy of Opto-Electronics Chinese Academy of Sciences Beijing

Along with the development of Global Navigation Satellite System （GNSS） and the deepening of research on Interoperability, more navigation satellites in space are able to provide Position Velocity and Time （PVT） service for users. Although added visible satellite number leads a better Geometric Dilution of Precision （GDOP）, there is not a conclusion about this GDOP improvement in quality. In this paper, we obtain another expression of GDOP using two variables, azimuth and elevation, instead of the used three direction cosines. Then, suppose the two variables as random variable, we obtain the expression of the mathematical expectation of GDOP, which means the average GDOP when the satellites randomly appear in the visible space. After that, considering the different block situation of user, the minimal elevation angle is imported as a constraint condition, and we obtain the expression of GDOP mathematical expectation with the minimal elevation angle limitation. Furthermore, a simulation process is adopted to verify the foregoing expressions. At last, an assessment model of GNSS constellation using the GDOP mathematical expectation is constructed and which is employed to evaluate the constellation of interoperability between different GNSSs.

关键词： GDOP mathematical expectation uniform distribution assessment model

Progress and Challenge of the Short-Term Climate Prediction

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Atmospheric and Oceanic Science Letters 2009年第5期2卷 267-270页

作者： Zeng Qing-Cun Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The experience of developing a short-term climate prediction system at the Institute of Atmospheric Science of the Chinese Academy of Sciences is summarized,and some problems to be solved in future are discussed in this *** is suggested that a good system for short-term climate prediction should at least consist of (1) well-tested model(s),(2) sufficient data and good methods for the initialization and assimilation,(3) a good system for quantitative corrections,(4) a good ensemble prediction method,and (5) appropriate prediction products,such as mathematical expectation,standard deviation,probability,among others.

关键词： short-term climate prediction ensemble prediction correction mathematical expectation standard deviation probability chaos

Some　Statistical　Properties　of　the　Correlation　Function　of　Combination　Sequences

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The Journal of China Universities of Posts and Telecommunications 1996年第1期3卷 53-58页

作者： Yu Kai Lu Chuanlai(Department of information Engineering. Beijing University of Posts and Telecommunications,Beijing, 100088,P.R.China)

in this paper,the statistical prOPerties of random combination sequences are *** of E{R(r)}and the upper bound of E{A(r)}are *** the end,a new method to find a longsequence with low autocorrelation value is given.

关键词： s:correlation function combination sequence mathematical expectation

MODIFICATION OF THE TIME STANDARD OF MOTIONS BASED ON mathematical STATISTICS OF COGNITIVE BEHAVIOR PARAMETERS

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MODIFICATION OF THE TIME STANDARD OF MOTIONS BASED ON MATHEM...

第十二届工业工程和工程管理国际会议

作者： FANG Qingguan GAO Zhenhua LI Bing Department of Industrial Engineering Anhui University of Technology Maanshan P. R. China 243002

＜正＞The time standard of basic motions in predetermination time analysis system is modified by u-sing testing data of cognitive behavior in human factor science. The method is presented to calculate mathematical expectation of each cognitive behavior parameter by using histogram on the mathematical statistics a-nalysis of test data of cognitive behavior. To the universal state of test data distribution, a calculating equation of modified value considering operators’ individual difference in cognitive behavior on basic motion time is e-duced from the method of MTM. The research of this paper shows the integration of cognitive psychology and industrial engineering technology which provides an improved method for the time analysis in modern production system.

关键词： mathematical expectation cognitive behavior predetermination time analysis system modificatio

MODIFICATION OF THE TIME STANDARD OF MOTIONS BASED ON mathematical STATISTICS OF COGNITIVE BEHAVIOR PARAMETERS

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MODIFICATION OF THE TIME STANDARD OF MOTIONS BASED ON MATHEM...

2005年中国机械工程学会年会

作者： FANG Qingguan, GAO Zhenhua, LI Bing (Department of Industrial Engineering, Anhui University of Technology, Maanshan, 243002)

＜正＞The time standard of basic motions in predetermination time analysis system is modified by using testing data of cognitive behavior in human factor science. The method is presented to calculate mathematical expectation of each cognitive behavior parameter by using histogram on the mathematical statistics analysis of test data of cognitive behavior. To the universal state of test data distribution, a calculating equation of modified value considering operators’ individual difference in cognitive behavior on basic motion time is educed from the method of MTM. The research of this paper shows the integration of cognitive psychology and industrial engineering technology which provides an improved method for the time analysis in modern production system.

关键词： mathematical expectation cognitive behavior predetermination time analysis system modificatio