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The Application of Goal-Setting Theory in the Second Classroom Teaching Activities of College English
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作者 宋琳琳 胡春华 《英语广场(学术研究)》 2012年第5期93-95,共3页
Interest is the precondition and motivation for people's accomplishment.However,due to the exam-oriented system,millions of parents and teachers neglect the interests of children,and our children nearly forget the... Interest is the precondition and motivation for people's accomplishment.However,due to the exam-oriented system,millions of parents and teachers neglect the interests of children,and our children nearly forget their interests or hobbies.Based on different interests of children,the thesis analyzes how to apply the goal-setting theory in the second classroom teaching activities of College English,using the example of Lushan College of Guangxi University of Technology. 展开更多
关键词 goal-setting theory second class teaching activities College English
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New Image Recognition Method Based on Rough-Sets and Fuzzy Theory 被引量:1
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作者 张艳 李凤霞 战守义 《Journal of Beijing Institute of Technology》 EI CAS 2003年第3期255-259,共5页
A new image recognition method based on fuzzy rough sets theory is proposed, and its implementation discussed. The performance of this method as applied to ferrography image recognition is evaluated. It is shown that... A new image recognition method based on fuzzy rough sets theory is proposed, and its implementation discussed. The performance of this method as applied to ferrography image recognition is evaluated. It is shown that the new method gives better results than fuzzy or rough sets method when used alone. 展开更多
关键词 fuzzy method rough sets theory image recognition
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La Shalle's invariant-set-theory based asymptotic synchronization of duffing system with unknown parameters
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作者 禹东川 吴爱国 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第1期95-99,共5页
A novel La Shalle's invariant set theory (LSIST) based adaptive asymptotic synchronization (LSISAAS) method is proposed to asymptotically synchronize Duffing system with unknown parameters which also are consider... A novel La Shalle's invariant set theory (LSIST) based adaptive asymptotic synchronization (LSISAAS) method is proposed to asymptotically synchronize Duffing system with unknown parameters which also are considered as system states. The LSISASS strategy depends on the only information, i.e. one state of the master system. According to the LSIST, the LSISASS method can asymptotically synchronize fully the states of the master system and the unknown system parameters as well. Simulation results also validate that the LSISAAS approach can obtain asymptotic synchronization. 展开更多
关键词 chaotic synchronization adaptive state observer La Shalle's invariant set theory
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Evaluation of the maintenance window scheme using fuzzy soft set theory
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作者 Changan Xu Shaoquan Ni Dingjun Chen 《Journal of Modern Transportation》 2018年第4期285-296,共12页
The maintenance window scheme(MWS) is one of the most important railway transportation organizational plans and plays an important role in ensuring railway operational safety. However, MWS setting is a very complicate... The maintenance window scheme(MWS) is one of the most important railway transportation organizational plans and plays an important role in ensuring railway operational safety. However, MWS setting is a very complicated process, and most countries currently do so with the help of a computer-aided decision system. In general, a decision system can generate multiple alternatives for MWS within an acceptable time. Therefore, how to choose the best option from the alternatives is a vital decision. This paper presents a novel framework for MWS evaluation based on the Chinese railway system. Specifically, the requirements of each department related to MWS setting are analysed, and we construct an evaluation indicator system for MWS based on the preferences of different departments. Then, we apply the fuzzy soft set theory to MWS evaluation, a method that not only effectively deals with evaluation of uncertain information, but also gives flexibility for experts to input their subjective judgment.Additionally, using the ‘‘AND’’ operation of soft set theory allows combing evaluation information from multiple evaluators to give comprehensive results. Finally, a case study illustrates the proposed framework, showing that the proposed evaluation indicator system and evaluation method are effective and practical. 展开更多
关键词 Railway transportation Maintenance window scheme Evaluation indicator system Fuzzy soft set theory
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Granularity of Knowledge Computed by Genetic Algorithms Based on Rough Sets Theory
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作者 Wenyuan Yang Xiaoping Ye +1 位作者 Yong Tang Pingping Wei 《南昌工程学院学报》 CAS 2006年第2期97-101,121,共6页
Rough set philosophy hinges on the granularity of data, which is used to build all its basic concepts, like approximations, dependencies, reduction etc. Genetic Algorithms provides a general frame to optimize problem ... Rough set philosophy hinges on the granularity of data, which is used to build all its basic concepts, like approximations, dependencies, reduction etc. Genetic Algorithms provides a general frame to optimize problem solution of complex system without depending on the domain of problem.It is robust to many kinds of problems.The paper combines Genetic Algorithms and rough sets theory to compute granular of knowledge through an example of information table. The combination enable us to compute granular of knowledge effectively.It is also useful for computer auto-computing and information processing. 展开更多
关键词 granularity of knowledge Genetic Algorithms Pawlak Model Rough set theory information table
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Rough Set Theory over Fuzzy Lattices
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作者 Guilong Liu 《南昌工程学院学报》 CAS 2006年第2期51-51,共1页
Rough set theory, proposed by Pawlak in 1982, is a tool for dealing with uncertainty and vagueness aspects of knowledge model. The main idea of rough sets corresponds to the lower and upper approximations based on equ... Rough set theory, proposed by Pawlak in 1982, is a tool for dealing with uncertainty and vagueness aspects of knowledge model. The main idea of rough sets corresponds to the lower and upper approximations based on equivalence relations. This paper studies the rough set and its extension. In our talk, we present a linear algebra approach to rough set and its extension, give an equivalent definition of the lower and upper approximations of rough set based on the characteristic function of sets, and then we explain the lower and upper approximations as the colinear map and linear map of sets, respectively. Finally, we define the rough sets over fuzzy lattices, which cover the rough set and fuzzy rough set,and the independent axiomatic systems are constructed to characterize the lower and upper approximations of rough set over fuzzy lattices,respectively,based on inner and outer products. The axiomatic systems unify the axiomization of Pawlak’s rough sets and fuzzy rough sets. 展开更多
关键词 OVER Rough set theory over Fuzzy Lattices
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Optimized numerical density functional theory calculation of rotationally symmetric jellium model systems
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作者 Guangdi Zhang Li Mao Hongxing Xu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期349-355,共7页
In real space density functional theory calculations,the effective potential depends on the electron density,requiring self-consistent iterations,and numerous integrals at each step,making the process time-consuming.I... In real space density functional theory calculations,the effective potential depends on the electron density,requiring self-consistent iterations,and numerous integrals at each step,making the process time-consuming.In our research,we propose an optimization method to expedite density functional theory(DFT)calculations for systems with large aspect ratios,such as metallic nanorods,nanowires,or scanning tunneling microscope tips.This method focuses on employing basis set to expand the electron density,Coulomb potential,and exchange-correlation potential.By precomputing integrals and caching redundant results,this expansion streamlines the integration process,significantly accelerating DFT computations.As a case study,we have applied this optimization to metallic nanorod systems of various radii and lengths,obtaining corresponding ground-state electron densities and potentials. 展开更多
关键词 density functional theory basis set integrals precomputation nanorod
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基于模糊逻辑与系统理论融合的地下储气库老井封堵施工风险评价方法
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作者 胡瑾秋 肖慈盼 +1 位作者 许子涵 刘若昕 《天然气工业》 北大核心 2025年第3期112-122,共11页
地下储气库(以下简称储气库)老井封堵施工,因井况复杂、动态交互性强,存在井筒窜气及封堵失效等高风险隐患。现有封堵井施工风险评价方法多依赖定性分析,难以量化关键因素间的非线性影响,且传统决策试验和评价实验室(DEMATEL)方法存在... 地下储气库(以下简称储气库)老井封堵施工,因井况复杂、动态交互性强,存在井筒窜气及封堵失效等高风险隐患。现有封堵井施工风险评价方法多依赖定性分析,难以量化关键因素间的非线性影响,且传统决策试验和评价实验室(DEMATEL)方法存在主观偏差问题。为此,基于模糊集理论改进DEMATEL算法,通过量化专家判断与引入原因度—中心度权重优化机制,构建了从系统级事故到不安全控制行为(UCA)的动态因果路径;然后结合概率阈值判定与多级风险传递分析,实现关键风险因素的定量排序与演化机理解析,最后建立了一种融合模糊逻辑与系统理论过程分析(Systematic Theory Process Analysis, STPA)的多尺度风险评价模型。研究结果表明:(1)融合改进的模糊DEMATEL与系统理论过程分析(STPA)方法能有效量化关键风险因素,通过引入原因度和中心度优化权重计算,显著降低了主观偏差,改进后方法的皮尔逊积矩(Pearson)相关系数优于传统模糊DEMATEL;(2)改进后的多级分析能对多个相互影响的风险因素进行多尺度的风险评价,确定不同风险因素的优化权重、相互间的因果关系、整体概率分布和传递路径;(3)多级风险传递路径分析揭示了不安全控制行为动态演化机制。结论认为,案例验证识别结果与施工现场实际风险高度吻合,该方法可以有效识别关键风险因素,且能够克服专家评价的模糊性与不确定性,为储气库老井封堵施工系统精准风险管控提供了理论和技术支撑。 展开更多
关键词 储气库 老井封堵 系统理论过程分析 模糊集理论 决策试验与评价实验室 施工风险评价
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基于Rough Set理论的铁路货运量预测 被引量:23
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作者 李红启 刘凯 《铁道学报》 EI CAS CSCD 北大核心 2004年第3期1-7,共7页
利用RoughSet理论通过对数据进行分析和推理发现隐含知识的优点,在结合该理论与铁路货运量预测要求的基础上,提出一个基于RoughSet理论的铁路货运量预测流程;合理选择统计指标并将相关原始数据代入预测流程涉及的各步骤后,得出预测我国... 利用RoughSet理论通过对数据进行分析和推理发现隐含知识的优点,在结合该理论与铁路货运量预测要求的基础上,提出一个基于RoughSet理论的铁路货运量预测流程;合理选择统计指标并将相关原始数据代入预测流程涉及的各步骤后,得出预测我国铁路货运量发展水平的规则集;利用该规则集预测了"十五"期间我国铁路货运量的发展水平;该规则集有望在我国"十一五"规划的制定中发挥一定的参考作用。 展开更多
关键词 ROUGH set理论 铁路货运量 预测
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基于改进DSets的无参数雷达信号分选算法 被引量:4
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作者 刘鲁涛 王璐璐 陈涛 《中国舰船研究》 CSCD 北大核心 2021年第4期232-238,共7页
[目的]随着电磁环境日益复杂,信号分选越来越困难。为了解决现有高效分选算法性能严重依赖于外界输入参数的不足,提出了基于DSets-DS的无参数雷达信号聚类算法。[方法]将直方图均衡化后的主导集(dominant sets,DSets)算法应用于雷达信... [目的]随着电磁环境日益复杂,信号分选越来越困难。为了解决现有高效分选算法性能严重依赖于外界输入参数的不足,提出了基于DSets-DS的无参数雷达信号聚类算法。[方法]将直方图均衡化后的主导集(dominant sets,DSets)算法应用于雷达信号分选,提出一种无参数的雷达信号脉冲聚类算法,然后结合D-S(Dempster-Shafer)证据理论,以解决DSets算法过度分割问题。[结果]在无任何先验信息条件下,能够完成对雷达信号混合脉冲精准聚类;此外,在虚假脉冲比例低于50%的情况下,分选正确率大于93.13%。将DSets算法与D-S证据理论结合,可有效完成对无先验信息的雷达信号脉冲聚类,且有很好的聚类性能。 展开更多
关键词 无参数聚类 主导集算法 直方图均衡 D-S证据理论
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基于Rough Set理论的典型振动故障诊断 被引量:2
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作者 李建兰 黄树红 张燕平 《动力工程》 EI CAS CSCD 北大核心 2008年第1期76-79,共4页
在分析旋转机械振动特点和Rough Set理论的基础上,针对传统的频谱分析方法对质量不平衡、动静碰摩、支座松动等3种典型故障识别效率低的缺点,提出了一个基于Rough Set的振动故障诊断模型.该模型根据故障和能量的映射关系,分别在时域、... 在分析旋转机械振动特点和Rough Set理论的基础上,针对传统的频谱分析方法对质量不平衡、动静碰摩、支座松动等3种典型故障识别效率低的缺点,提出了一个基于Rough Set的振动故障诊断模型.该模型根据故障和能量的映射关系,分别在时域、频域、时-频域中定义4种信息熵作为条件属性,推导了3种典型振动的决策规则,实现了对振动信号中不一致信息的处理.通过汽轮发电机组振动实验对上述方法进行了验证.结果表明,该模型能够很好地识别这3种典型故障. 展开更多
关键词 能源与动力工程 汽轮发电机组 振动 故障诊断 ROUGH set理论 信息熵
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非理想爆轰波阵面传播的Level Set方法应用研究 被引量:1
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作者 姜洋 钟敏 +2 位作者 孙承纬 李平 柏劲松 《兵工学报》 EI CAS CSCD 北大核心 2010年第7期896-901,共6页
为了较精确地对非理想爆轰波的传播进行计算,基于爆轰冲击波动力学(DSD)理论,研究了计算二维贴体坐标系中爆轰波阵面传播问题的Level Set方法。根据Ham ilton-Jacobi方程的Godunov差分格式,提出了非正交的贴体坐标系中Level Set函数方... 为了较精确地对非理想爆轰波的传播进行计算,基于爆轰冲击波动力学(DSD)理论,研究了计算二维贴体坐标系中爆轰波阵面传播问题的Level Set方法。根据Ham ilton-Jacobi方程的Godunov差分格式,提出了非正交的贴体坐标系中Level Set函数方程的差分格式及其相应的数值方法。将Level Set方法应用于自行研制的二维流体动力学程序TDY2D得到编码TDY_DSD,对爆轰波的传播及爆轰驱动的实验模型进行了数值模拟计算,所得的计算值均与实验值符合较好。计算结果表明了TDY_DSD程序的正确性和有效性,具有较高计算精度。 展开更多
关键词 爆炸力学 爆轰驱动 爆轰冲击波动力学理论 Level-set方法 贴体坐标系 数值模拟
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基于Rough Set和综合评判的进场航班排序 被引量:2
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作者 高伟 张云霞 《航空计算技术》 2015年第1期5-9,共5页
终端区资源的高效利用对空中交通流量管理效率的提高具有重要作用,进场航班排序是终端区资源利用的关键环节,所以需要研究终端区进场航班的排序问题。利用模糊综合评判方法,考虑排序过程中的多种影响因素建立综合评判指标体系,根据粗糙... 终端区资源的高效利用对空中交通流量管理效率的提高具有重要作用,进场航班排序是终端区资源利用的关键环节,所以需要研究终端区进场航班的排序问题。利用模糊综合评判方法,考虑排序过程中的多种影响因素建立综合评判指标体系,根据粗糙集理论客观地确定各评判指标权重。利用算例对基于粗糙集理论的模糊综合评判方法进行了验证,表明方法在终端区排序问题中的可行性和有效性。 展开更多
关键词 终端区 粗糙集理论 进场航班排序 模糊综合评判
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变精度Rough Sets模型在数据挖掘中的应用
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作者 王志龙 李向新 《兰州工业高等专科学校学报》 2011年第1期19-22,共4页
经典的粗糙集理论在进行分类时其类之间的分界线很严格,这样提高了知识属性对被研究对象识别分类的精度,但这种方式的容错能力很差,使得模型的实际适用性很弱.变精度粗糙集是对经典粗糙集理论的一种扩展,通过研究得出了知识的依赖程度... 经典的粗糙集理论在进行分类时其类之间的分界线很严格,这样提高了知识属性对被研究对象识别分类的精度,但这种方式的容错能力很差,使得模型的实际适用性很弱.变精度粗糙集是对经典粗糙集理论的一种扩展,通过研究得出了知识的依赖程度饱和值不变约简法及信息熵不减约简法. 展开更多
关键词 数据挖掘 粗糙集理论 变精度粗糙集理论 知识约简
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加权自适应多粒度决策理论粗糙集模型
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作者 张宇 汪小燕 《安徽工业大学学报(自然科学版)》 2025年第2期178-188,共11页
多粒度粗糙集涉及属性权重时,通常利用指定的方式设定,而对于属性颗粒结构对应的上、下近似集计算所需的概率阈值也常依赖于专家建议设定,这使得现有粗糙集模型在实际应用中缺乏适应性。为此,提出1种加权自适应多粒度决策理论粗糙集模型... 多粒度粗糙集涉及属性权重时,通常利用指定的方式设定,而对于属性颗粒结构对应的上、下近似集计算所需的概率阈值也常依赖于专家建议设定,这使得现有粗糙集模型在实际应用中缺乏适应性。为此,提出1种加权自适应多粒度决策理论粗糙集模型(weighted adaptive multi-granulation decision-theoretic rough sets,WAMG-DTRS)。通过信息增益计算属性粒度的权重,并通过设置权重系数控制颗粒结构数目。同时,利用单参数决策理论粗糙集中的阈值公式确定属性颗粒结构中不同对象对应的上、下近似集计算所需的概率阈值,从而使模型更好地适应实际应用需求。在WAMG-DTRS模型的基础上,进一步构建5种平均加权自适应多粒度决策理论粗糙集模型,以进一步提高模型应用的适应性。通过实例和实验验证,结果表明:调整权重系数可灵活调整WAMG-DTRS模型的上、下近似集规模;不同平均条件下的WAMG-DTRS模型展现出不同的下近似集特性,并具备WAMG-DTRS模型灵活调控权重系数的能力。通过综合考虑不同平均条件,可以进一步提升模型的适应性。 展开更多
关键词 自适应阈值 权重 多粒度 决策理论 粗糙集 信息增益 粒计算
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A Decision Model Based on Grey Rough Sets Integration with Incomplete Information 被引量:5
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作者 HOU Ya-lin LUO Dang 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第1期151-158,共8页
In this paper, for multiple attribute decision-making problem in which attribute values are interval grey numbers and some of them are null values, a decision model based on grey rough sets integration with incomplete... In this paper, for multiple attribute decision-making problem in which attribute values are interval grey numbers and some of them are null values, a decision model based on grey rough sets integration with incomplete information is proposed. We put forward incidence degree coefficient formula for grey interval, by information entropy theory and analysis technique, the method and principle is presented to fill up null values. We also establish the method of grey interval incidence cluster. Because grey system theory and Rough set theory are complementary each other, decision table with preference information is obtained by the result of grey incidence cluster. An algorithm for inducing decision rules based on rough set theory and the dominance relationship is presented. In some extent, this algorithm can deal with decision-making problem in which the attribute values are interval grey numbers and some of them are null values. Contrasted with classical model of cluster decision-making, the algorithm has an advantage of flexibility and compatibility to new information. 展开更多
关键词 grey system theory rough set incidence cluster interval grey number entropy null value
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基于Vague Sets-topsis理论的爆破方案优选 被引量:2
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作者 李小贝 蒙云琪 +1 位作者 吴剑锋 吝学飞 《爆破》 CSCD 北大核心 2018年第2期94-100,共7页
为了解决复杂框架结构楼房爆破拆除过程中如何选择爆破方案的技术难题,建立改进的Vague Sets-topsis综合评价指标模型,对爆破方案进行优选。首先对爆破方案中的关键参数建立评审指标集;然后利用逼近理想解的排序法,计算出各个方案的综... 为了解决复杂框架结构楼房爆破拆除过程中如何选择爆破方案的技术难题,建立改进的Vague Sets-topsis综合评价指标模型,对爆破方案进行优选。首先对爆破方案中的关键参数建立评审指标集;然后利用逼近理想解的排序法,计算出各个方案的综合优越度,从而确定各个爆破方案的优劣;最后以铁四院前大楼爆破为例,采用改进的Vague Sets-topsis理论模型对"内向折叠爆破"(S1)、"双向折叠爆破"(S2)和"单向折叠双切口爆破"(S3)等不同方案的关键参数进行综合对比分析,得到方案的最优排序为:S3>S2>S1。实际爆破拆除实例表明:S3拆除效果良好,证明采用改进的Vague Sets-topsis理论模型可以用于复杂框架结构楼房控制爆破拆除优选。 展开更多
关键词 爆破拆除 VAGUE sets-topsis理论 折叠爆破 爆破效果
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Representations of Co-regular Subsets on Euclidean Spaces 被引量:2
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作者 邱玉文 王莉萍 赵希顺 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第2期252-257,共6页
For the computability of co-regular subsets in metric spaces, the properties of the co-regular subsets and several reasonable representations on co-regular sets have been suggested in this paper. As last, the 'weaker... For the computability of co-regular subsets in metric spaces, the properties of the co-regular subsets and several reasonable representations on co-regular sets have been suggested in this paper. As last, the 'weaker or stronger' relations of these representations have been revealed. 展开更多
关键词 type-2 theory of effectivity COMPUTABILITY computable set REPRESENTATIONS
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Investigations on Nuclei near Z = 82 in Relativistic Mean Field Theory with FSUGold
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作者 圣宗强 任中洲 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第6期534-538,共5页
In this work, the ground-state properties of Pt, Hg, Pb, and Po isotopes have been systematically investigated in the deformed relativistic mean field (RMF) theory with the new parameter set FSUGold. The calculated ... In this work, the ground-state properties of Pt, Hg, Pb, and Po isotopes have been systematically investigated in the deformed relativistic mean field (RMF) theory with the new parameter set FSUGold. The calculated results show that FSUGold is as successful as NL3 in reproducing the ground-state binding energies of the nuclei in this region. The calculated two- neutron separation energies, quadrupole deformations, and root-mean-square charge radii are in agreement with the experimental data. The parameter set FSUGold can successfully describe the shell effect of the neutron magic number N = 126 and give smaller neutron skin thicknesses than NL3 for all the nuclei considered. 展开更多
关键词 relativistic mean field theory parameter set FSUGold binding energy DEFORMATION
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根据DS理论的船舶风险因素评估分析 被引量:2
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作者 李成海 刘树锋 胡甚平 《广东交通职业技术学院学报》 2024年第2期64-68,共5页
针对船舶航行风险评估中存在许多不确定影响因素的问题,提出了在模糊风险评估证据理论基础上建立的风险评估方法。在证据集理论空间中,每一事件均可确认为模糊集合子集且融入了模糊概率理论,从而更全面地描述行业学者的专业经验或证据诠... 针对船舶航行风险评估中存在许多不确定影响因素的问题,提出了在模糊风险评估证据理论基础上建立的风险评估方法。在证据集理论空间中,每一事件均可确认为模糊集合子集且融入了模糊概率理论,从而更全面地描述行业学者的专业经验或证据诠释,由此得出了模糊证据理论质量函数的描述法。最后应用其船舶安全系统,提出了船舶风险因素识别和风险评估详细程序。计算结果证明,此方法可有效避免决策失误,且简单、易行,有较强的推广和应用价值。 展开更多
关键词 水上运输 船舶航行 船舶风险评估 模糊证据理论 模糊集合子集
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