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Self-determinate evaluation method based on condition of weights non-dictatorial rate 被引量:3
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作者 Zhang Danning Yi Pingtao Guo Yajun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期310-320,共11页
The condition of weightes non-dictatorship is extended and a comprehensive evaluae method emboding self-determinate which is combined with competitive view optimization principles is built. The basic process includes ... The condition of weightes non-dictatorship is extended and a comprehensive evaluae method emboding self-determinate which is combined with competitive view optimization principles is built. The basic process includes simulating the model of economic man's self-benefit bahaviors, taking the place of experts to evaluate, bringing in the model of minimizing the sum of included angles to integrate the information of multiple objects and put the objects in order finally. The method has the advangtages of less dependendence on the subjective information, plenty of information, fair process and simple caculating. Finally, an application example is given to illustrate the effectiveness of the proposed method. 展开更多
关键词 condition of weights non-dictatorial rate principle of competitive view optimization self-determinate evaluation comprehensive evaluation
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Effect of electric boundary conditions on crack propagation in ferroelectric ceramics 被引量:2
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作者 F.-X. Li Y.Sun R.K.N.D.Rajapakse 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第2期153-160,共8页
In this paper, the effect of electric boundary conditions on Mode I crack propagation in ferroelectric ceramics is studied by using both linear and nonlinear piezoelectric fracture mechanics. In linear analysis, imper... In this paper, the effect of electric boundary conditions on Mode I crack propagation in ferroelectric ceramics is studied by using both linear and nonlinear piezoelectric fracture mechanics. In linear analysis, impermeable cracks under open circuit and short circuit are analyzed using the Stroh formalism and a rescaling method. It is shown that the energy release rate in short circuit is larger than that in open circuit. In nonlinear analysis, permeable crack conditions are used and the nonlinear effect of domain switching near a crack tip is considered using an energy-based switching criterion proposed by Hwang et al.(Acta Metal. Mater.,1995). In open circuit, a large depolarization field induced by domain switching makes switching much more diffcult than that in short circuit. Analysis shows that the energy release rate in short circuit is still larger than that in open circuit, and is also larger than the linear result. Consequently,whether using linear or nonlinear fracture analysis, a crack is found easier to propagate in short circuit than in open circuit, which is consistent with the experimental observations of Kounga Njiwa et al.(Eng. Fract. Mech., 2006). 展开更多
关键词 Ferroelectric ceramics Crack propagation En-ergy release rate Electric boundary conditions Domain switching
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MAPPING CLOSURE APPROXIMATION FOR REACTIVE SCALARS IN RANDOM FLOWS
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作者 张子范 何国威 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2004年第4期340-346,共7页
The Mapping Closure Approximation(MCA)approach is developed to describe the statistics of both conserved and reactive scalars in random flows.The statistics include Probability Density Function(PDF),Conditional Dissip... The Mapping Closure Approximation(MCA)approach is developed to describe the statistics of both conserved and reactive scalars in random flows.The statistics include Probability Density Function(PDF),Conditional Dissipation Rate(CDR)and Conditional Laplacian(CL).The statistical quantities are calculated using the MCA and compared with the results of the Direct Nu- merical Simulation(DNS).The results obtained from the MCA are in agreement with those from the DNS.It is shown that the MCA approach can predict the statistics of reactive scalars in random flows. 展开更多
关键词 conserved and reactive scalars MCA probability density function conditional dissipation rate conditional Laplacian
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A Comparison of Two Linear Discriminant Analysis Methods That Use Block Monotone Missing Training Data
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作者 Phil D. Young Dean M. Young Songthip T. Ounpraseuth 《Open Journal of Statistics》 2016年第1期172-185,共14页
We revisit a comparison of two discriminant analysis procedures, namely the linear combination classifier of Chung and Han (2000) and the maximum likelihood estimation substitution classifier for the problem of classi... We revisit a comparison of two discriminant analysis procedures, namely the linear combination classifier of Chung and Han (2000) and the maximum likelihood estimation substitution classifier for the problem of classifying unlabeled multivariate normal observations with equal covariance matrices into one of two classes. Both classes have matching block monotone missing training data. Here, we demonstrate that for intra-class covariance structures with at least small correlation among the variables with missing data and the variables without block missing data, the maximum likelihood estimation substitution classifier outperforms the Chung and Han (2000) classifier regardless of the percent of missing observations. Specifically, we examine the differences in the estimated expected error rates for these classifiers using a Monte Carlo simulation, and we compare the two classifiers using two real data sets with monotone missing data via parametric bootstrap simulations. Our results contradict the conclusions of Chung and Han (2000) that their linear combination classifier is superior to the MLE classifier for block monotone missing multivariate normal data. 展开更多
关键词 Linear Discriminant Analysis Monte Carlo Simulation Maximum Likelihood Estimator Expected Error Rate conditional Error Rate
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Energy efficient HARQ scheme for wireless communication over block fading channel
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作者 Wu Yue Yang Hongwen 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2015年第3期35-40,共6页
Energy efficiency (EE) can be enhanced by retransmissions and combining in hybrid automatic repeat request (HARQ) system. However, it is difficult to optimize the transmit power of each retransmission when the acc... Energy efficiency (EE) can be enhanced by retransmissions and combining in hybrid automatic repeat request (HARQ) system. However, it is difficult to optimize the transmit power of each retransmission when the accurate retransmission number and future channel state information (CSI) cannot be obtained. This paper proposes a simple energy efficient HARQ scheme for point-to-point wireless communication. In the proposed scheme, the conditional word error rate (WER) of each retransmission is fixed and the transmit power is adapted correspondingly. Three performance metrics are analyzed including average transmission number, throughput and EE. Compared with the conventional equal power HARQ scheme, the proposed scheme can significantly improve the EE and other two metrics under the same constraint of average transmit power or average energy consumption. Furthermore, it is found that, selecting a conditional WER which is slightly smaller than the optimal one is sufficient for practical implementation. 展开更多
关键词 Energy efficiency hybrid automatic repeat request (HARQ) conditional word error rate
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