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A Disturbance Localization Method for Power System Based on Group Sparse Representation and Entropy Weight Method
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作者 Zeyi Wang Mingxi Jiao +4 位作者 Daliang Wang Minxu Liu Minglei Jiang He Wang Shiqiang Li 《Energy Engineering》 EI 2024年第8期2275-2291,共17页
This paper addresses the problem of complex and challenging disturbance localization in the current power system operation environment by proposing a disturbance localization method for power systems based on group sp... This paper addresses the problem of complex and challenging disturbance localization in the current power system operation environment by proposing a disturbance localization method for power systems based on group sparse representation and entropy weight method.Three different electrical quantities are selected as observations in the compressed sensing algorithm.The entropy weighting method is employed to calculate the weights of different observations based on their relative disturbance levels.Subsequently,by leveraging the topological information of the power system and pre-designing an overcomplete dictionary of disturbances based on the corresponding system parameter variations caused by disturbances,an improved Joint Generalized Orthogonal Matching Pursuit(J-GOMP)algorithm is utilized for reconstruction.The reconstructed sparse vectors are divided into three parts.If at least two parts have consistent node identifiers,the node is identified as the disturbance node.If the node identifiers in all three parts are inconsistent,further analysis is conducted considering the weights to determine the disturbance node.Simulation results based on the IEEE 39-bus system model demonstrate that the proposed method,utilizing electrical quantity information from only 8 measurement points,effectively locates disturbance positions and is applicable to various disturbance types with strong noise resistance. 展开更多
关键词 Disturbance location compressed sensing group sparse representation entropy power method GOMP algorithm
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Risk Assessment of Diary Cattle Brucellosis Based on Systematic Multilevel Grey Relation Entropy Method
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作者 孙向东 江慎铭 刘拥军 《Agricultural Science & Technology》 CAS 2012年第10期2169-2174,2225,共7页
[Objective] The study was to explore the major factors affecting diary cattle brucellosis risk assessment,as well as their strong-to-weak sequence,so as to provide theoretical basis for assessing diary cattle brucello... [Objective] The study was to explore the major factors affecting diary cattle brucellosis risk assessment,as well as their strong-to-weak sequence,so as to provide theoretical basis for assessing diary cattle brucellosis risk level in different regions.[Method] From 4 dimensions of feeding and importing,breeding,housing and polyculture situation,an evaluation index system was set up,and diary cattle brucellosis risk survey was conducted in 3 typical regions.Finally,systematic multilevel grey relation entropy method was applied to perform data analysis.[Result] The strong-to-weak sequence of Level 1 impact factor of diary cattle brucellosis was as follows:feeding and importinghousingpolyculture situationbreeding;the sequence of Level 2 impact factor was U32〉U12〉U11〉U31〉U21〉U42〉U43〉U23〉U22〉U41;the risk level sequence of 3 typical regions was Province A(County A1,A2,A3)Province B(County B1,B2,B3)Province C(County C1,C2,C3).[Conclusion] According to the weight of Level 1 index strata,administrative departments at all levels and dairy cattle farmers should lay emphasis on the aspects of feeding,importing and housing;viewed from the perspective of Level 2 index strata,dairy cattle farmers should value the siting of cattle field,the brucellosis surveillance before importing and milking modes most.According to the diary cattle brucellosis risk level of 3 typical regions,if administrative departments at all levels strengthen peoples' awareness of their personal health and increase investment in this area,with new healthy cultured atmosphere built,the risk level of diary cattle brucellosis will surly decline. 展开更多
关键词 Systematic multilevel grey relation entropy method Diary cattle brucellosis Risk assessment
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基于DEMATEL和熵权法的生鲜食品网购决策影响因素研究
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作者 杨力 《河北北方学院学报(自然科学版)》 2024年第5期53-59,共7页
随着电子商务生活化的普及,生鲜行业也日趋电商化。生鲜电商企业面对日益增长的市场规模的同时也面临着日益激烈的行业竞争。生鲜电商企业通过识别客户购买决策的影响因素并进行重要性排序,可以有的放矢地改进工作,进而可以提高消费者... 随着电子商务生活化的普及,生鲜行业也日趋电商化。生鲜电商企业面对日益增长的市场规模的同时也面临着日益激烈的行业竞争。生鲜电商企业通过识别客户购买决策的影响因素并进行重要性排序,可以有的放矢地改进工作,进而可以提高消费者完成购买的转化率、促进商家的商品销量。通过构建影响客户网购生鲜食品决策的指标体系,采用DEMATEL方法确定各影响要素的地位及其因果关系。为了克服DEMATEL法专家评价主观的局限性,使用客观赋权的熵权法计算出熵权值,利用乘法合成法进行组合赋权,通过组合权重排序分析得出电商平台信誉度、电商平台知名度、售后服务完善度、电商平台管理规范度、生鲜食品品质、生鲜食品品牌知名度、配送的保鲜度、配送快捷性是影响消费者网购生鲜食品决策的重要因素。因此,生鲜电商商家可以从选择优质的第三方平台、优化店铺服务流程、建立生鲜食品质量保证体系等方面加以改进,进一步提升网络消费者生鲜食品的购买转化。 展开更多
关键词 生鲜食品 网购决策 影响因素 DemATEL 熵权法
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基于DEMATEL-Entropy法的城市轨道交通应急预案评价方法研究 被引量:2
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作者 姜少涌 李健 +1 位作者 刘志钢 朱雅茹 《物流工程与管理》 2023年第1期112-115,共4页
在城市轨道交通应急预案评价过程中,往往存在评价指标主观性过强以及评价结果难以量化等问题,因此文中提出了决策实验室法(DEMATEL法)和熵权法(Entropy法)相结合的评价方法。首先建立由4个准则层和12个指标层组成的城市轨道交通应急预... 在城市轨道交通应急预案评价过程中,往往存在评价指标主观性过强以及评价结果难以量化等问题,因此文中提出了决策实验室法(DEMATEL法)和熵权法(Entropy法)相结合的评价方法。首先建立由4个准则层和12个指标层组成的城市轨道交通应急预案评价指标体系,然后使用DEMATEL法和Entropy法求得指标的主观权重和客观权重,运用博弈论计算综合权重,再通过模糊综合评价法计算待评预案的最终得分和评级等级。最后,选取城市轨道交通某应急预案对模型的可行性进行了验证,为预案评价提供了新思路。 展开更多
关键词 城市轨道交通 预案评价 决策实验室方法 熵权法 模糊综合评价
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RELIABILITY ASSESSMENT OF ENTROPY METHOD FOR SYSTEM CONSISTED OF IDENTICAL EXPONENTIAL UNITS 被引量:5
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作者 SunYouchao ShiJun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第4期502-506,共5页
The reliability assessment of unit-system near two levels is the mostimportant content in the reliability multi-level synthesis of complex systems. Introducing theinformation theory into system reliability assessment,... The reliability assessment of unit-system near two levels is the mostimportant content in the reliability multi-level synthesis of complex systems. Introducing theinformation theory into system reliability assessment, using the addible characteristic ofinformation quantity and the principle of equivalence of information quantity, an entropy method ofdata information conversion is presented for the system consisted of identical exponential units.The basic conversion formulae of entropy method of unit test data are derived based on the principleof information quantity equivalence. The general models of entropy method synthesis assessment forsystem reliability approximate lower limits are established according to the fundamental principleof the unit reliability assessment. The applications of the entropy method are discussed by way ofpractical examples. Compared with the traditional methods, the entropy method is found to be validand practicable and the assessment results are very satisfactory. 展开更多
关键词 Reliability synthesis Data conversion entropy method Information quantity Exponential unit
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Construction of Conservative Numerical Fluxes for the Entropy Split Method
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作者 Björn Sjögreen H.C.Yee 《Communications on Applied Mathematics and Computation》 2023年第2期653-678,共26页
The entropy split method is based on the physical entropies of the thermally perfect gas Euler equations.The Euler flux derivatives are approximated as a sum of a conservative portion and a non-conservative portion in... The entropy split method is based on the physical entropies of the thermally perfect gas Euler equations.The Euler flux derivatives are approximated as a sum of a conservative portion and a non-conservative portion in conjunction with summation-by-parts(SBP)difference boundary closure of(Gerritsen and Olsson in J Comput Phys 129:245-262,1996;Olsson and Oliger in RIACS Tech Rep 94.01,1994;Yee et al.in J Comp Phys 162:33-81,2000).Sj?green and Yee(J Sci Comput)recently proved that the entropy split method is entropy conservative and stable.Stand-ard high-order spatial central differencing as well as high order central spatial dispersion relation preserving(DRP)spatial differencing is part of the entropy stable split methodol-ogy framework.The current work is our first attempt to derive a high order conservative numerical flux for the non-conservative portion of the entropy splitting of the Euler flux derivatives.Due to the construction,this conservative numerical flux requires higher oper-ations count and is less stable than the original semi-conservative split method.However,the Tadmor entropy conservative(EC)method(Tadmor in Acta Numerica 12:451-512,2003)of the same order requires more operations count than the new construction.Since the entropy split method is a semi-conservative skew-symmetric splitting of the Euler flux derivative,a modified nonlinear filter approach of(Yee et al.in J Comput Phys 150:199-238,1999,J Comp Phys 162:3381,2000;Yee and Sj?green in J Comput Phys 225:910934,2007,High Order Filter Methods for Wide Range of Compressible flow Speeds.Proceedings of the ICOSAHOM09,June 22-26,Trondheim,Norway,2009)is proposed in conjunction with the entropy split method as the base method for problems containing shock waves.Long-time integration of 2D and 3D test cases is included to show the com-parison of these new approaches. 展开更多
关键词 Finite-difference method entropy conservation entropy splitting Shock capturing
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An Information Entropy-Based Methodology to Construct the Avulsion Threshold in the Tail Reach of the Estuarine Alluvial Plain
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作者 YANG Zhuo-yuan XIA Jun-qiang +3 位作者 DENG Shan-shan ZHOU Mei-rong JI Zu-wen YU Xin 《China Ocean Engineering》 SCIE EI CSCD 2023年第5期794-806,共13页
Channel avulsion is a natural phenomenon that occurs abruptly on alluvial river deltas,which can affect the channel stability.The causes for avulsion could be generally categorized as topography-and flood-driven facto... Channel avulsion is a natural phenomenon that occurs abruptly on alluvial river deltas,which can affect the channel stability.The causes for avulsion could be generally categorized as topography-and flood-driven factors.However,previous studies on avulsion thresholds usually focused on topography-driven factors due to the centurial or millennial avulsion timescales of the world’s most deltas,but neglected the impacts of flood-driven factors.In the current study,a novel demarcation equation including the two driven factors was proposed,with the decadal timescale of avulsion being considered in the Yellow River Estuary(YRE).In order to quantify the contributions of different factors in each category,an entropy-based methodology was used to calculate the contributing weights of these factors.The factor with the highest weight in each category was then used to construct the demarcation equation,based on avulsion datasets associated with the YRE.An avulsion threshold was deduced according to the demarcation equation.This avulsion threshold was then applied to conduct the risk assessment of avulsion in the YRE.The results show that:two dominant factors cover respectively geomorphic coefficient representing the topography-driven factor and fluvial erosion intensity representing the flood-driven factor,which were thus employed to define a two dimensional mathematical space in which the demarcation equation can be obtained;the avulsion threshold derived from the equation was also applied in the risk assessment of avulsion;and the avulsion threshold proposed in this study is more accurate,as compared with the existing thresholds. 展开更多
关键词 avulsion threshold threshold conditions entropy weight method tail reach Yellow River Estuary
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The deconvolution of lunar brightness temperature based on the maximum entropy method using Chang'e-2 microwave data 被引量:1
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作者 Shu-Guo Xing Yan Su +1 位作者 Jian-Qing Feng Chun-Lai Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第2期293-304,共12页
A passive and multi-channel microwave sounder onboard the Chang'e-2 orbiter has successfully acquired microwave observations of the lunar surface and subsurface structure. Compared with the Chang'e-1 orbiter, the Ch... A passive and multi-channel microwave sounder onboard the Chang'e-2 orbiter has successfully acquired microwave observations of the lunar surface and subsurface structure. Compared with the Chang'e-1 orbiter, the Chang'e-2 orbiter obtained more accurate and comprehensive microwave brightness temperature data, which are helpful for further research. Since there is a close relationship between mi- crowave brightness temperature data and some related properties of the lunar regolith, such as the thickness, temperature and dielectric constant, precise and high resolution brightness temperature data are necessary for such research. However, through the detection mechanism of the microwave sounder, the brightness temperature data ac- quired from the microwave sounder are weighted by the antenna radiation pattern, so the data are the convolution of the antenna radiation pattern with the lunar brightness temperature. In order to obtain the real lunar brightness temperature, a deconvolution method is needed. The aim of this paper is to solve the problem associated with per- forming deconvolution of the lunar brightness temperature. In this study, we introduce the maximum entropy method (MEM) to process the brightness temperature data and achieve excellent results. The paper mainly includes the following aspects: first, we introduce the principle of the MEM; second, through a series of simulations, the MEM has been verified as an efficient deconvolution method; and third, the MEM is used to process the Chang'e-2 microwave data and the results are significant. 展开更多
关键词 space vehicles instruments: microwave sounder Moon: brightness temperature methods: maximum entropy method
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基于改进DEMATEL—ISM法的地铁司机人因失误致因链分析
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作者 何静 许佳璐 +2 位作者 石杰红 丁晨辉 刘伟 《中国安全生产科学技术》 CAS CSCD 北大核心 2024年第10期204-212,共9页
为提高地铁司机在行车作业过程中的人因可靠性,保障地铁行车安全,结合地铁司机正线行车作业特点,确定15个地铁司机人因失误致因因素,通过引入熵权法,对决策实验室分析法—解释结构模型法(DEMATEL-ISM法)进行改进,并建立地铁司机失误致... 为提高地铁司机在行车作业过程中的人因可靠性,保障地铁行车安全,结合地铁司机正线行车作业特点,确定15个地铁司机人因失误致因因素,通过引入熵权法,对决策实验室分析法—解释结构模型法(DEMATEL-ISM法)进行改进,并建立地铁司机失误致因因素递阶结构模型,确定关键致因链。研究结果表明:失误致因因素递阶结构模型为六层,地铁司机人因失误致因链共36条,其中“紧急情况的辨别—信息通报的及时准确—调度命令的理解及执行—掌握列车操作步骤—完成清客作业—正确完成出退勤工作”为关键致因链,紧急情况的辨别是最根本的致因因素。研究结果可为地铁司机人因失误管控、制定现场操作规范提供参考依据。 展开更多
关键词 地铁司机 致因链 熵权法 改进DemATEL-ISM法 人因失误
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Natural Convection and Irreversibility of Nanofluid Due to Inclined Magnetohydrodynamics(MHD)Filled in a Cavity with Y-Shape Heated Fin:FEM Computational
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作者 Afraz Hussain Majeed Rashid Mahmood +3 位作者 Sayed M.Eldin Imran Saddique S.Saleem Muhammad Jawad 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1505-1519,共15页
This study explains the entropy process of natural convective heating in the nanofluid-saturated cavity in a heated fin andmagnetic field.The temperature is constant on the Y-shaped fin,insulating the topwall while th... This study explains the entropy process of natural convective heating in the nanofluid-saturated cavity in a heated fin andmagnetic field.The temperature is constant on the Y-shaped fin,insulating the topwall while the remaining walls remain cold.All walls are subject to impermeability and non-slip conditions.The mathematical modeling of the problem is demonstrated by the continuity,momentum,and energy equations incorporating the inclined magnetic field.For elucidating the flow characteristics Finite ElementMethod(FEM)is implemented using stable FE pair.A hybrid fine mesh is used for discretizing the domain.Velocity and thermal plots concerning parameters are drawn.In addition,a detailed discussion regarding generation energy by monitoring changes in magnetic,viscous,total,and thermal irreversibility is provided.In addition,line graphs are created for the u and v components of the velocity profile to predict the flow behavior.Current simulations assume the dimensionless representative of magnetic field Hartmann number Ha between 0 and 100 and a magnetic field inclination between 0 and 90 degrees.A constant 4% volume proportion of nanoparticles is employed throughout all scenarios. 展开更多
关键词 Finite element method nanomaterials entropy MHD square cavity Y-fin
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基于EM-FR-C5.0DT耦合模型的输气管道地质灾害风险预测模型
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作者 艾昕宇 何鹏 +6 位作者 孟祥振 王新刚 李玉星 刘鹏 韩建红 梁裕如 由洋 《油气与新能源》 2024年第4期84-96,107,共14页
延安气田地处陕北山区,输气管道沿线发生地质灾害的风险较高,管道生产运行存在一定安全隐患,通过加强风险预测研究,可快速准确甄别沿线高后果区,对管道防灾减灾具有重要意义。为此,选取延安气田内部临镇-子长输气干线作为研究对象。首先... 延安气田地处陕北山区,输气管道沿线发生地质灾害的风险较高,管道生产运行存在一定安全隐患,通过加强风险预测研究,可快速准确甄别沿线高后果区,对管道防灾减灾具有重要意义。为此,选取延安气田内部临镇-子长输气干线作为研究对象。首先,通过相关性分析筛选出高程等11个影响因子,依次开展灾点空间分布规律研究;其次,采用加权频率比法将灾点属性值转换为可体现灾害风险贡献率的EM-FR(加权频率值),划分出低、极低风险区,在此范围内选取非灾点,以此构建EM-FR-C5.0DT(加权频率比-C5.0决策树)、EM-FR-BP(加权频率比-BP神经网络)等2种耦合模型,并预测研究区域的风险性;最后,在研究区域内随机选取非灾点,构建单一C5.0DT、BP模型,并与上述2种耦合模型开展精度对比分析。结果显示:耦合模型预测性能优于单一模型,其中EM-FR-C5.0DT模型效果最优。研究成果表明,在低、极低风险区内,选取非灾点构建数据集得到的耦合模型,可明显提升模型预测精度,更适合小样本地质灾害风险性建模,可为延安气田输气管道风险性研究提供一定借鉴。 展开更多
关键词 输气管道 熵值法 C5.0决策树 BP神经网络 风险性预测
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CoCrFeMnNi高熵合金组织与力学性能研究进展
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作者 谢马冲 杨坤 李来平 《中国材料进展》 CAS CSCD 北大核心 2024年第7期627-636,共10页
等原子比CoCrFeMnNi合金是目前研究最为深入的高熵合金之一,具有许多超越传统合金的优异性能,包括良好的室温塑性、稳定的相结构、优异的低温力学性能等,具有巨大的发展潜力和广泛的应用前景。总结梳理了不同制备工艺下CoCrFeMnNi高熵... 等原子比CoCrFeMnNi合金是目前研究最为深入的高熵合金之一,具有许多超越传统合金的优异性能,包括良好的室温塑性、稳定的相结构、优异的低温力学性能等,具有巨大的发展潜力和广泛的应用前景。总结梳理了不同制备工艺下CoCrFeMnNi高熵合金的组织特点,简要讨论了现有制备工艺的优缺点。重点分析论述了该合金的力学性能和变形行为,主要包括各种强化手段对合金力学性能的影响规律,以及合金在高温和低温下的力学性能和变形机制,介绍了合金相稳定性的相关研究进展。最后探讨了限制该合金发展的主要问题,对其未来发展方向进行了展望。 展开更多
关键词 高熵合金 CoCrFemnNi 制备工艺 力学性能 相稳定性
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Spatiotemporal evolution and influencing factors of urban resilience in the Yellow River Basin,China
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作者 JI Xiaomei NIE Zhilei +2 位作者 WANG Kaiyong XU Mingxian FANG Yuhao 《Regional Sustainability》 2024年第3期54-68,共15页
The Yellow River Basin of China is a key region that contains myriad interactions between human activities and natural environment.Industrialization and urbanization promote social-economic development,but they also h... The Yellow River Basin of China is a key region that contains myriad interactions between human activities and natural environment.Industrialization and urbanization promote social-economic development,but they also have generated a series of environmental and ecological issues in this basin.Previous researches have evaluated urban resilience at the national,regional,urban agglomeration,city,and prefecture levels,but not at the watershed level.To address this research gap and elevate the Yellow River Basin’s urban resilience level,we constructed an urban resilience evaluation index system from five dimensions:industrial resilience,social resilience,environmental resilience,technological resilience,and organizational resilience.The entropy weight method was used to comprehensively evaluate urban resilience in the Yellow River Basin.The exploratory spatial data analysis method was employed to study the spatiotemporal differences in urban resilience in the Yellow River Basin in 2010,2015,and 2020.Furthermore,the grey correlation analysis method was utilized to explore the influencing factors of these differences.The results of this study are as follows:(1)the overall level of urban resilience in the Yellow River Basin was relatively low but showed an increasing trend during 2010–2015,and significant spatial distribution differences were observed,with a higher resilience level in the eastern region and a low-medium resilience level in the western region;(2)the differences in urban resilience were noticeable,with industrial resilience and social resilience being relatively highly developed,whereas organizational resilience and environmental resilience were relatively weak;and(3)the correlation ranking of resilience influencing factors was as follows:science and technology level>administrative power>openness>market forces.This research can provide a basis for improving the resilience level of cities in the Yellow River Basin and contribute to the high-quality development of the region. 展开更多
关键词 Urban resilience Spatiotemporal evolution entropy weight method Exploratory spatial data analysis method Grey correlation analysis method Yellow River Basin
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Reliability Allocation of Large Mining Excavator Electrical System Based on the Entropy Method with Failure and Maintenance Data
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作者 胡天松 黄洪钟 +2 位作者 王晓明 李光 高素荷 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期779-781,共3页
In the design of large mining excavator electrical system,a practical reliability allocation method was introduced to allocate system level reliability requirements into subsystem and component levels. During the reli... In the design of large mining excavator electrical system,a practical reliability allocation method was introduced to allocate system level reliability requirements into subsystem and component levels. During the reliability allocation process,factors from the fault and maintenance data were only considered in reliability allocation scheme. It could avoid the disturbance from expert experiences. The entropy method was also used to obtain weights of reliability allocation indexes of large mining excavators considering different factors. Then the failure rate allocation of subsystems and components could be completed. 展开更多
关键词 reliability allocation large mining excavators the entropy method
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基于Co-CEM的柔性车间调度优化算法
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作者 张政 徐鹏 +2 位作者 孟宇龙 卢中玉 邹家睿 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第3期480-488,共9页
为解决船舶制造中的柔性作业车间调度问题,本文提出一种基于协同进化策略的交叉熵算法来提高船舶制造过程的效率。协同进化策略弥补了交叉熵算法局部搜索能力较弱的问题,提高解的质量;提出基于主动调度的遗传解码算法,保证得到的解属于... 为解决船舶制造中的柔性作业车间调度问题,本文提出一种基于协同进化策略的交叉熵算法来提高船舶制造过程的效率。协同进化策略弥补了交叉熵算法局部搜索能力较弱的问题,提高解的质量;提出基于主动调度的遗传解码算法,保证得到的解属于活动调度;遗传操作将相关调度信息保存在基因中,有效提高算法的搜索效率。本文通过实验对比遗传解码与常用的插入式解码算法,验证了解码算法的有效性及其提升能力,与现有具有竞争力的算法进行对比,证明了基于协同进化策略的交叉熵算法的高效性与优越性,给出了优质的甘特图。 展开更多
关键词 组合优化 柔性作业车间调度 进化算法 交叉熵算法 PARETO支配 协同进化 主动调度 船舶制造
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Reliability Optimization of Entropy Based Series-Parallel System Using Global Criterion Method
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作者 G. S. MAHAPATRA 《Intelligent Information Management》 2009年第3期145-149,共5页
In this paper, we have considered a series-parallel system to find out optimum system reliability with an additional entropy objective function. Maximum system reliability of series-parallel system is depending on pro... In this paper, we have considered a series-parallel system to find out optimum system reliability with an additional entropy objective function. Maximum system reliability of series-parallel system is depending on proper allocation of redundancy component in different stage. The goal of entropy based reliability redundancy allocation problem is to find optimal number of redundancy component in each stage such a manner that maximize the system reliability subject to available total system cost. Global criterion method is used to analyze entropy based reliability optimization problem with different weight function of objective functions. Numerical examples have been provided to illustrate the model. 展开更多
关键词 RELIABILITY SERIES-PARALLEL system REDUNDANCY entropy GLOBAL CRITERION method
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An Entropy Measurement Method of Quantum Information System under Uncertain Environment
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作者 Zijing Li Jiangnan Deng +2 位作者 Bing Zhou Ying Liu Zhengying Cai 《International Journal of Intelligence Science》 2018年第2期29-41,共13页
Under uncertain environment, it is very difficult to measure the entropy of quantum information system, because there is no effective method to model the randomness. First, different from the traditional classic uncer... Under uncertain environment, it is very difficult to measure the entropy of quantum information system, because there is no effective method to model the randomness. First, different from the traditional classic uncertainty, a quantum uncertain model is proposed to simulate a quantum information system under uncertain environment, and to simplify the entropy measurement of quantum information system. Second, different from the classic random seed under uncertain environment which is often called as pseudo-random number, here the quantum random is employed to provide us a true random model for the entropy of quantum information system. Third, the complex interaction and entangling activity of uncertain factors of quantum information is modeled as quantum binary instead of classic binary, which can help us to evaluate the entropy of uncertain environment, to analyze the entropy divergence in quantum information system. This work presents a non-classic risk factor measurement for quantum information system and a helpful entropy measurement. 展开更多
关键词 entropy Measurement method QUANTUM Information System UNCERTAIN ENVIRONMENT QUANTUM ENCRYPTION
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Measurement and Evaluation of the Business Environment in Large and Medium-Sized Cities in China
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作者 Yi Zhang 《Proceedings of Business and Economic Studies》 2024年第3期75-79,共5页
The comprehensive development level of the business environment reflects the quality of a region’s economic development,and a good business environment will give a city a strong vitality.This paper uses the entropy m... The comprehensive development level of the business environment reflects the quality of a region’s economic development,and a good business environment will give a city a strong vitality.This paper uses the entropy method to measure and evaluate the business environment of 106 large and medium-sized cities in China from 2017 to 2021.The results show that:From the spatial point of view,the business environment index of China’s cities shows a gradually decreasing pattern from east to west and from south to north.The balance of the business environment of large and medium-sized cities in China is divided into four levels according to the standard deviation of the ranking of each subindex.The greater the standard deviation,the more unbalanced the overall development of the business environment in the region.Finally,this paper put forward countermeasures and suggestions to further optimize the business environment. 展开更多
关键词 Business environment Evaluation system entropy evaluation method
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Research Progress of High Entropy Ceramic Materials
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作者 Song WU Shikai LIU +5 位作者 Jialin WANG Bibo HAN Shaoyi SHEN Zhigang YU Zhaobo ZHANG Xinhua ZHENG 《Research and Application of Materials Science》 2024年第1期16-22,共7页
High-entropy materials(HEMs)have better mechanical,thermal,and electrical properties than traditional materials due to their special"high entropy effect".They can also adjust the performance of high entropy ... High-entropy materials(HEMs)have better mechanical,thermal,and electrical properties than traditional materials due to their special"high entropy effect".They can also adjust the performance of high entropy ceramics by adjusting the proportion of raw materials,and have broad application prospects in many fields.This article provides a review of the high entropy effect,preparation methods,and main applications of high entropy ceramic materials,especially exploring relevant research on high entropy perovskite ceramics.It is expected to provide reference for the promotion of scientific research and the development of further large-scale applications of high-entropy ceramic materials. 展开更多
关键词 High-entropy ceramic materials high entropy effect preparation method perovskite structure research prog
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Application of geophysical methods in fine detection of urban concealed karst:A case study of Wuhan City,China
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作者 Dao-han Liu Lei Wang +3 位作者 Lei Liu Jun-jie Xu Jian-qiang Wu Pan Liu 《China Geology》 CAS CSCD 2024年第3期517-532,共16页
The construction of modern livable cities faces challenges in karst areas,including ground collapse and engineering problems.Wuhan,with a population of 13.74×10^(6) and approximately 1161 km^(2)of soluble rocks i... The construction of modern livable cities faces challenges in karst areas,including ground collapse and engineering problems.Wuhan,with a population of 13.74×10^(6) and approximately 1161 km^(2)of soluble rocks in the urban area of 8569.15 km^(2),predominantly consists of concealed karst areas where occasional ground collapse events occur,posing significant threats to underground engineering projects.To address these challenges,a comprehensive geological survey was conducted in Wuhan,focusing on major karstrelated issues.Geophysical methods offer advantages over drilling in detecting concealed karst areas due to their efficiency,non-destructiveness,and flexibility.This paper reviewed the karst geological characteristics in Wuhan and the geophysical exploration methods for karst,selected eight effective geophysical methods for field experimentation,evaluated their suitability,and proposed method combinations for different karst scenarios.The results show that different geophysical methods have varying applicability for karst detection in Wuhan,and combining multiple methods enhances detection effectiveness.The specific recommendations for method combinations provided in this study serve as a valuable reference for karst detection in Wuhan. 展开更多
关键词 Ground Penetrating Radar(GPR) Electric Resistivity Tomography(ERT) Opposing-coils Transient Electromagnetic method(OCTem) Microtremor Array Measurements(MAM) Multi-channel Analysis of surface wave(MASW) Multi-source surface wave exploration(MSSW) Electromagnetic wave CT(em CT) Surface Nuclear Magnetic Resonance(SNMR) Concealed karst Urban geological survey engineering
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