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Effect of the interval between two shocks on ejecta formation from the grooved aluminum surface
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作者 Mingyang Xu Jianli Shao +1 位作者 Weidong Song Enling Tang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期147-159,共13页
This work focuses on the effect of the interval between two shocks on the ejecta formation from the grooved aluminum(Al_(1100))surface by using smoothed particle hydrodynamics numerical simulation.Two unsupported shoc... This work focuses on the effect of the interval between two shocks on the ejecta formation from the grooved aluminum(Al_(1100))surface by using smoothed particle hydrodynamics numerical simulation.Two unsupported shocks are obtained by the plate-impact between sample and two flyers at interval,with a peak pressure of approximately 30 GPa for each shock.When the shock interval varies from 2.11 to 7.67 times the groove depth,the bubble velocity reduces to a constant,and the micro jetting factor R_(J) from spike to bubble exhibits a non-monotonic change that decreases initially and then increases.At a shock interval of 3.6 times the groove depth,micro jetting factor R_(J) from spike to bubble reaches its minimum value of approximately 0.6.While,the micro jetting factor R_(F) from spike to free surface decreases linearly at first,and stabilizes around 0.25 once the shock interval surpasses 4.18 times the groove depth.When the shock interval is less than 4.18 times the groove depth,the unloading wave generated by the breakout of the first shock wave is superimpose with the unloading part of the second shock wave to form a large tensile area. 展开更多
关键词 EJECTA MICROJET Two shocks interval Smoothed particle hydrodynamics
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Parameter Interval Estimation for Yule-Simon Distribution
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作者 DENG Wenli WANG Liming WANG Jinglong 《应用概率统计》 CSCD 北大核心 2024年第6期1000-1015,共16页
Yule-Simon distribution has a wide range of practical applications, such as in networkscience, biology and humanities. A lot of work focuses on the study of how well the empirical datafits Yule-Simon distribution or h... Yule-Simon distribution has a wide range of practical applications, such as in networkscience, biology and humanities. A lot of work focuses on the study of how well the empirical datafits Yule-Simon distribution or how to estimate the parameter. There are still some open problems,such as the error analysis of parameter estimation, the theoretical proof of the convergence of theiterative algorithm for maximum likelihood estimation of parameters. The Yule-Simon distributionis a heavy-tailed distribution and the parameter is usually less than 2, so the variance does notexist. This makes it difficult to give an interval estimation of the parameter. Using the compressiontransformation, this paper proposes a method of interval estimation based on the centrallimit theorem. This method can be applied to many heavy-tailed distributions. The other twoasymptotic confidence intervals of the parameter are obtained based on the maximum likelihoodand the mode method. These estimation methods are compared in simulations and applications toempirical data. 展开更多
关键词 Yule-Simon distribution maximum likelihood estimation confidence interval compression transformation
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Interval^+——一种基于区间树的压缩XML索引结构1,222 被引量:1
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作者 包小源 唐世渭 杨冬青 《计算机研究与发展》 EI CSCD 北大核心 2006年第7期1285-1290,共6页
XML在数据交换中的应用越来越广泛,但由于标记引入而使其空间膨胀较大,对传输及存储资源耗费严重.压缩后的XML数据容量明显减少,但怎样基于压缩后的XML数据直接进行查询及处理,仍然是需要深入研究的问题.以反向算术压缩为基本压缩算法,... XML在数据交换中的应用越来越广泛,但由于标记引入而使其空间膨胀较大,对传输及存储资源耗费严重.压缩后的XML数据容量明显减少,但怎样基于压缩后的XML数据直接进行查询及处理,仍然是需要深入研究的问题.以反向算术压缩为基本压缩算法,提出针对XML数据库中压缩XML文件的索引结构Interval+,基于该索引结构,可高效实现对类似element1element2…elmentm的查询处理. 展开更多
关键词 XML 索引 区间树 算术压缩
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Interval grey number sequence prediction by using non-homogenous exponential discrete grey forecasting model 被引量:20
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作者 Naiming Xie Sifeng Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第1期96-102,共7页
This paper aims to study a new grey prediction approach and its solution for forecasting the main system variable whose accurate value could not be collected while the potential value set could be defined. Based on th... This paper aims to study a new grey prediction approach and its solution for forecasting the main system variable whose accurate value could not be collected while the potential value set could be defined. Based on the traditional nonhomogenous discrete grey forecasting model(NDGM), the interval grey number and its algebra operations are redefined and combined with the NDGM model to construct a new interval grey number sequence prediction approach. The solving principle of the model is analyzed, the new accuracy evaluation indices, i.e. mean absolute percentage error of mean value sequence(MAPEM) and mean percent of interval sequence simulating value set covered(MPSVSC), are defined and, the procedure of the interval grey number sequence based the NDGM(IG-NDGM) is given out. Finally, a numerical case is used to test the modelling accuracy of the proposed model. Results show that the proposed approach could solve the interval grey number sequence prediction problem and it is much better than the traditional DGM(1,1) model and GM(1,1) model. 展开更多
关键词 grey number grey system theory interval discrete grey forecasting model non-homogeneous exponential sequence
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New approach to determine the priorities from interval fuzzy preference relations 被引量:7
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作者 Qi Yue Zhiping Fan Lihua Shi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第2期267-273,共7页
An approach is proposed to solve the problem how to obtain the priorities from interval fuzzy preference relations. Firstly, another expression of interval numbers is given. Then, some basic definitions on consistency... An approach is proposed to solve the problem how to obtain the priorities from interval fuzzy preference relations. Firstly, another expression of interval numbers is given. Then, some basic definitions on consistency and weak transitivity of real and interval fuzzy preference relations are described. Based on these definitions, a two-phase process for determining the priorities from interval fuzzy preference relations is presented. Finally, two exam- ples are used to illustrate the use of the proposed approach. 展开更多
关键词 interval fuzzy preference relation CONSISTENCY weaktransitivity priority.
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New approach to multiple attribute decision making with interval numbers 被引量:7
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作者 Zhang Quan Gao Qisheng Geng Jinhua 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第2期304-310,共7页
In an ambiguous decision domain, the evaluation values of alternatives against attributes would be interval numbers because of the inherent, uncertain property of the problems. By using a number of linear programming ... In an ambiguous decision domain, the evaluation values of alternatives against attributes would be interval numbers because of the inherent, uncertain property of the problems. By using a number of linear programming models, Bryson and Mobolurin propose an approach to compute attribute weights and overall values of the alternatives in the form of interval numbers. The intervals of the overall values of alternatives are then transformed into points or crisp values for comparisons among the alternatives. However, the attribute weights are different because of the use of linear programming models in Bryson and Mobolurin's approach. Thus, the alternatives are not comparable because different attribute weights are employed to calculate the overall values of the alternatives. A new approach is proposed to overcome the drawbacks of Bryson and Mobolurin's approach. By transforming the decision matrix with intervals into the one with crisp values, a new linear programming model is proposed, to calculate the attribute weights for conducting alternative ranking. 展开更多
关键词 multiple attribute decision making interval number NORMALIZATION programming model ranking.
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Prediction model of interval grey number based on DGM(1,1) 被引量:19
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作者 Bo Zeng Sifeng Liu Naiming Xie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第4期598-603,共6页
In grey system theory,the studies in the field of grey prediction model are focused on real number sequences,rather than grey number ones.Hereby,a prediction model based on interval grey number sequences is proposed.B... In grey system theory,the studies in the field of grey prediction model are focused on real number sequences,rather than grey number ones.Hereby,a prediction model based on interval grey number sequences is proposed.By mining the geometric features of interval grey number sequences on a two-dimensional surface,all the interval grey numbers are converted into real numbers by means of certain algorithm,and then the prediction model is established based on those real number sequences.The entire process avoids the algebraic operations of grey number,and the prediction problem of interval grey number is usefully solved.Ultimately,through an example's program simulation,the validity and practicability of this novel model are verified. 展开更多
关键词 grey system theory prediction model interval grey number grey number band grey number layer DGM(1 1) model.
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Improved unequal interval grey model and its applications 被引量:5
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作者 Yuhong Wang Yaoguo Dang Xujin Pu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第3期445-451,共7页
A new method to improve prediction precision of GM(1,1) model with unequal time interval is presented.The grey derivative is multiplied by a parameter to guarantee the time response function satisfying approximately... A new method to improve prediction precision of GM(1,1) model with unequal time interval is presented.The grey derivative is multiplied by a parameter to guarantee the time response function satisfying approximately exponential function distribution.To simplify the process of parametric estimation,an approximate value is taken for the multiplied parameter.Then the estimators of coefficient of development and grey action quantity can be derived.At the same time,the principle of the new information priority is also considered.We take the last item of the first-order accumulated generation operator(1-AGO) on raw data sequence as the initial condition in the time response function.Then the new information can be taken full advantage of through the improved initial condition.Some properties of this new model are also discussed.The presented method is actually a combination of improvement of grey derivative and improvement of the initial condition.The results of an example indicate that the proposed method can improve prediction precision prominently. 展开更多
关键词 grey derivative initial condition GM(1 1) model unequal interval.
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Multiple-target tracking with adaptive sampling intervals for phased-array radar 被引量:10
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作者 Zhenkai Zhang Jianjiang Zhou +2 位作者 Fei Wang Weiqiang Liu Hongbing Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第5期760-766,共7页
A novel adaptive sampling interval algorithm for multitarget tracking is presented. This algorithm which is based on interacting multiple models incorporates the grey relational grade (GRG) into the particle swarm o... A novel adaptive sampling interval algorithm for multitarget tracking is presented. This algorithm which is based on interacting multiple models incorporates the grey relational grade (GRG) into the particle swarm optimization (PSO). Firstly, the desired tracking accuracy is set for each target. Secondly, sampling intervals are selected as particles, and then the advantage of the GRG is taken as the measurement function for resource management. Meanwhile, the fitness value of the PSO is used to measure the difference between desired tracking accuracy and estimated tracking accuracy. Finally, it is suggested that the radar should track the target whose prediction value of the next sampling interval is the smallest. Simulations show that the proposed method improves both the tracking accuracy and tracking efficiency of the phased-array radar. 展开更多
关键词 target tracking adaptive sampling interval (ASI) particle swarm optimization (PSO) grey relational grade (GRG) phased-array radar.
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Graphic theory on interval stability of networked control systems 被引量:3
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作者 Li Jinna Zhang Qingling 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第6期1185-1190,共6页
A new method on the interval stability of networked control systems (NCSs) with random delay and data packet dropout is studied. Combining interval systems and NCSs, a graphic condition on judging interval stability... A new method on the interval stability of networked control systems (NCSs) with random delay and data packet dropout is studied. Combining interval systems and NCSs, a graphic condition on judging interval stability is presented in terms of the weighted diagraph theory in graph theory. Furthermore, utilizing the graph-theoretic algorithm, the delay-depended controller gains are obtained. Aiming at the same delay and data packed dropout, several controller gains are obtained, simultaneously. The example and simulation illustrate the effectiveness of the proposed method. 展开更多
关键词 networked control systems interval stability weighted diagraph vertex matrix.
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Variable scheduling interval task scheduling for phased array radar 被引量:4
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作者 ZHANG Haowei XIE Junwei +2 位作者 ZHANG Zhaojian SHAO Lei CHEN Tangjun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第5期937-946,共10页
A scheduling algorithm is presented aiming at the task scheduling problem in the phased array radar. Rather than assuming the scheduling interval(SI) time, which is the update interval of the radar invoking the schedu... A scheduling algorithm is presented aiming at the task scheduling problem in the phased array radar. Rather than assuming the scheduling interval(SI) time, which is the update interval of the radar invoking the scheduling algorithm, to be a fixed value,it is modeled as a fuzzy set to improve the scheduling flexibility.The scheduling algorithm exploits the fuzzy set model in order to intelligently adjust the SI time. The idle time in other SIs is provided for SIs which will be overload. Thereby more request tasks can be accommodated. The simulation results show that the proposed algorithm improves the successful scheduling ratio by 16%,the threat ratio of execution by 16% and the time utilization ratio by 15% compared with the highest task mode priority first(HPF)algorithm. 展开更多
关键词 phased array radar task scheduling variable scheduling interval(SI) fuzzy set
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Approach for air-to-air confrontment based on uncertain interval information conditions 被引量:4
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作者 LI Qiuni YANG Rennong +1 位作者 FENG Chao LIU Zongcheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第1期100-109,共10页
Model combat information conditions are always uncertain and varied, the uncertain interval theory is therefore introduced into the research of multiple fighters suppressing the integrated air defense system(IADS) pro... Model combat information conditions are always uncertain and varied, the uncertain interval theory is therefore introduced into the research of multiple fighters suppressing the integrated air defense system(IADS) problem. Considering that the combat information conditions are uncertain intervals, the payoff function of the game for multiple fighters suppressing the IADS is modeled.Using the operation rules for interval numbers and the possibility degree, an improved chaotic particle swarm optimization(CPSO)is designed to solve the proposed model so as to obtain the optimal game solution. Comparison simulations are performed to analyze the influence of the weapons consumption and the distances of non-escaped zone and jamming on air combat result. Simulation results suggest that Nash equilibrium is achieved and verify the effectiveness of the proposed method. 展开更多
关键词 interval information integrated AIR DEFENSE system (IADS) AIR COMBAT CHAOTIC particle SWARM optimization (CPSO) game.
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SLIP RATE AND RECURRENCE INTERVAL OF STRONG EARTHQUAKE OF QIANNING—KANGDING SEGMENT ON XIANSHUIHE FAULT 被引量:2
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作者 Zhou Rongjun, He Yulin, Huang Zhuzhi, Li Xiaogang, Yang Tao(Engineer Earthquake Institute of Seismological Bureau of Sichuan Province, Chengdu 610041,China) 《地学前缘》 EI CAS CSCD 2000年第S1期297-298,共2页
Located on the western of Sichuan, the east border of Tibet plateau, Xianshuihe fault is a significant strong earthquake zone. From Huiyuansi pull\|apart basin in Qianning, Xianshuihe fault can be divided two segments... Located on the western of Sichuan, the east border of Tibet plateau, Xianshuihe fault is a significant strong earthquake zone. From Huiyuansi pull\|apart basin in Qianning, Xianshuihe fault can be divided two segments\|NW section and SE section: the construction of the former is single and a main fault; the construction of the latter is complex and composed by three parallel faults, its main fault is named as Selaha—Kangding fault, which distributes along Jinlongsi, Sehala, Mugecuo and Kangding. Yalahe fault, located at the NE direction of the main fault, and Zeduotang fault, located at the SW direction of the main fault, are all secondary faults, which are 9~13km away from the main fault. At the south of Kangding, the segment of Xianshuihe fault is a single main section, called as Moxi fault. On the basis of recent researching results, this paper mainly discusses the slip rate and recurrence interval of strong earthquake of the SE segment (Qianning—Kangding) on Xianshuihe. 展开更多
关键词 SLIP rate RECURRENCE interval FAULTING LANDFORM paleoea rthquake seismic TENDENCY
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Multi-criteria linguistic interval group decision-making approach 被引量:2
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作者 Wang Jianqiang ChenXiaohong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第5期934-938,共5页
For group decision-making problems with linguistic assessment information, a new method based on two-tuple and WC-OWA operator is proposed, in which the criteria's weights and the decision-makers' preference informa... For group decision-making problems with linguistic assessment information, a new method based on two-tuple and WC-OWA operator is proposed, in which the criteria's weights and the decision-makers' preference information might take the form of linguistic grade, or might be between two continuous linguistic grades, or might be linguistic interval, or might be default. In this method, all linguistic values are transformed into two-tuple, and an aggregative decision-making matrix is obtained by using interval operation. The group aggregative values of each criterion on alternatives are computed by using a WC-OWA operator, the aggregative values on alternatives are worked out, and transformed into two-tuple. And the rank of the alternatives is obtained by using the order property of two-tuple. An example shows the feasibility and effectiveness of the proposed method. 展开更多
关键词 multi-criteria decision making group decision-making two-tuple linguistic interval WC-OWA operator.
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Passivity analysis for uncertain stochastic neural networks with discrete interval and distributed time-varying delays 被引量:3
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作者 P.Balasubramaniam G.Nagamani 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第4期688-697,共10页
The problem of passivity analysis is investigated for uncertain stochastic neural networks with discrete interval and distributed time-varying delays.The parameter uncertainties are assumed to be norm bounded and the ... The problem of passivity analysis is investigated for uncertain stochastic neural networks with discrete interval and distributed time-varying delays.The parameter uncertainties are assumed to be norm bounded and the delay is assumed to be time-varying and belongs to a given interval,which means that the lower and upper bounds of interval time-varying delays are available.By constructing proper Lyapunov-Krasovskii functional and employing a combination of the free-weighting matrix method and stochastic analysis technique,new delay-dependent passivity conditions are derived in terms of linear matrix inequalities(LMIs).Finally,numerical examples are given to show the less conservatism of the proposed conditions. 展开更多
关键词 linear matrix inequality(LMI) stochastic neural network PASSIVITY interval time-varying delay Lyapunov method.
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Risk assessment of water inrush in tunnels based on attribute interval recognition theory 被引量:6
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作者 WANG Sheng LI Li-ping +3 位作者 CHENG Shuai HU Hui-jiang ZHANG Ming-guang WEN Tao 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第2期517-530,共14页
Water inrush is one of the most serious geological hazards in underground engineering construction.In order to effectively prevent and control the occurrence of water inrush,a new attribute interval recognition theory... Water inrush is one of the most serious geological hazards in underground engineering construction.In order to effectively prevent and control the occurrence of water inrush,a new attribute interval recognition theory and method is proposed to systematically evaluate the risk of water inrush in karst tunnels.Its innovation mainly includes that the value of evaluation index is an interval rather than a certain value;the single-index attribute evaluation model is improved non-linearly based on the idea of normal distribution;the synthetic attribute interval analysis method based on improved intuitionistic fuzzy theory is proposed.The TFN-AHP method is proposed to analyze the weight of evaluation index.By analyzing geological factors and engineering factors in tunnel zone,a multi-grade hierarchical index system for tunnel water inrush risk assessment is established.The proposed method is applied to ventilation incline of Xiakou tunnel,and its rationality and practicability is verified by comparison with field situation and evaluation results of other methods.In addition,the results evaluated by this method,which considers that water inrush is a complex non-linear system and the geological conditions have spatial variability,are more accurate and reliable.And it has good applicability in solving the problem of certain and uncertain problem. 展开更多
关键词 water inrush risk assessment attribute interval recognition model TFN-AHP
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Multi-attributed decision making for mining methods based on grey system and interval numbers 被引量:8
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作者 刘浪 陈建宏 +1 位作者 王革民 劳德正 《Journal of Central South University》 SCIE EI CAS 2013年第4期1029-1033,共5页
In the case of unknown weights, theories of multi-attributed decision making based on interval numbers and grey related analysis were used to optimize mining methods. As the representative of independence for the indi... In the case of unknown weights, theories of multi-attributed decision making based on interval numbers and grey related analysis were used to optimize mining methods. As the representative of independence for the indicator, the smaller the correlation of indicators is, the greater the weight is. Hence, the weights of interval numbers of indicators were determined by using correlation coefficient. Relative closeness based on positive and negative ideal methods was calculated by introducing distance between interval numbers, which made decision making more rational and comprehensive. A new method of ranking interval numbers based on normal distribution was proposed for the optimization of mining methods, whose basic properties were discussed. Finally, the feasibility and effectiveness of this method were verified by theories and practice. 展开更多
关键词 mining method interval number multi-attributed decision making grey related analysis correlation coefficient normaldistribution RANKING
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Improved delay-dependent stability criteria for systems with interval delay 被引量:1
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作者 Hongbing Zeng Shenping Xiao Bin Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第6期998-1002,共5页
This paper deals with the problem of stability for systems with delay varying in an interval.A new Lyapunov functional,which makes use of the information of both the lower and upper bounds of the interval time-varying... This paper deals with the problem of stability for systems with delay varying in an interval.A new Lyapunov functional,which makes use of the information of both the lower and upper bounds of the interval time-varying delay,is proposed to derive some new stability criteria.Furthermore,the relationship of the time-varying delay and its lower bound and upper bound is taken into account.As a result,some less conservative delay-dependent stability criteria are obtained without ignoring any useful information in the derivative of Lyapunov functional,which are established in the forms of linear matrix inequalities.Numerical examples are provided to show that the obtained results are better than existing ones. 展开更多
关键词 stability criteria interval delay DELAY-DEPENDENT linear matrix inequality(LMI).
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The AMSAA-BISE Model with Gap Intervals 被引量:1
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作者 Zhou Yuanquan and Weng Zhaoxi(Beijing Institute of Structure and Environment) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1990年第1期77-83,共7页
In this paper, the AMSAA-BISE model with missing data is discussed. The ML estimates of model parameters and current MTBF are given, and the chi-squared test and a plot for cumulative number of failures versus cumulat... In this paper, the AMSAA-BISE model with missing data is discussed. The ML estimates of model parameters and current MTBF are given, and the chi-squared test and a plot for cumulative number of failures versus cumulative testing time are used to test the goodness of fit for the model. This paper concludes with a numerical example to verify the model. 展开更多
关键词 Reliability growth Gap interval Missing data AMSAA-BISE model.
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Discrete logistics network design model under interval hierarchical OD demand based on interval genetic algorithm 被引量:2
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作者 李利华 符卓 +1 位作者 周和平 胡正东 《Journal of Central South University》 SCIE EI CAS 2013年第9期2625-2634,共10页
Aimed at the uncertain characteristics of discrete logistics network design,an interval hierarchical triangular uncertain OD demand model based on interval demand and network flow is presented.Under consideration of t... Aimed at the uncertain characteristics of discrete logistics network design,an interval hierarchical triangular uncertain OD demand model based on interval demand and network flow is presented.Under consideration of the system profit,the uncertain demand of logistics network is measured by interval variables and interval parameters,and an interval planning model of discrete logistics network is established.The risk coefficient and maximum constrained deviation are defined to realize the certain transformation of the model.By integrating interval algorithm and genetic algorithm,an interval hierarchical optimal genetic algorithm is proposed to solve the model.It is shown by a tested example that in the same scenario condition an interval solution[3275.3,3 603.7]can be obtained by the model and algorithm which is obviously better than the single precise optimal solution by stochastic or fuzzy algorithm,so it can be reflected that the model and algorithm have more stronger operability and the solution result has superiority to scenario decision. 展开更多
关键词 uncertainty interval planning hierarchical OD logistics network design genetic algorithm
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