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Upper and Lower Semicontinuity of Solution Sets for Parametric Generalized Vector Quasi-equilibrium Problems
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作者 LI AI-QIN FAN LI-YA 《Communications in Mathematical Research》 CSCD 2011年第1期1-5,共5页
In this paper, two kinds of parametric generalized vector quasi-equilibrium problems are introduced and the relations between them are studied. The upper and lower semicontinuity of their solution sets to parameters a... In this paper, two kinds of parametric generalized vector quasi-equilibrium problems are introduced and the relations between them are studied. The upper and lower semicontinuity of their solution sets to parameters are investigated. 展开更多
关键词 parametric generalized vector quasi-equilibrium problem solution set upper semicontinuity lower semicontinuity set-valued mapping
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Some Characterizations of Upper and Lower M-Asymmetric Preirresolute Multifunctions
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作者 Levy Kahyata Matindih Elijah Bwanga Mpelele +1 位作者 Jimmy Hambulo Davy Kabuswa Manyika 《Advances in Pure Mathematics》 2023年第5期267-283,共17页
In this present paper, we introduce and investigate a new form of mappings namely;upper and lower M-asymmetric preirresolute multifunctions defined between M-structural asymmetric topological spaces. The relationships... In this present paper, we introduce and investigate a new form of mappings namely;upper and lower M-asymmetric preirresolute multifunctions defined between M-structural asymmetric topological spaces. The relationships between the multifunctions in our sense and other types of precountinuous and preirresolute multifunctions defined on both symmetric and asymmetric topological structures are discussed. 展开更多
关键词 Asymmetric-Preopen sets M-Space M-Asymmetric Preopen sets upper (lower) Preirresolute Multifunctions upper (lower) M-Asymmetric Preirresolute Multifunctions
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On <i>M</i>-Asymmetric Semi-Open Sets and Semicontinuous Multifunctions in Bitopological Spaces 被引量:2
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作者 Levy K. Matindih Edwin Moyo 《Advances in Pure Mathematics》 2021年第4期218-236,共19页
The purpose of this paper is to introduce the notions of <em>m</em>-asymmetric semiopen sets and <em>M</em>-asymmetric semicontinuous multifunctions defined between asymmetric sets satisfying c... The purpose of this paper is to introduce the notions of <em>m</em>-asymmetric semiopen sets and <em>M</em>-asymmetric semicontinuous multifunctions defined between asymmetric sets satisfying certain minimal conditions in the framework of bitopological spaces. Some new characterizations of <em>m</em>-asymmetric semiopen sets and <em>M</em>-asymmetric semicontinuous multifunctions will be investigated and several fundamental properties will be obtained. 展开更多
关键词 m-Spaces m-Semiasymmetric Open and Closed sets upper and lower M-Asymmetric Semicontinuous Multifunction
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Rough Integrals Generated by Function Rough Sets 被引量:1
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作者 YU Xiu-qing XU Feng-sheng 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第2期296-299,共4页
The concepts of the lower approximation integral,the upper approximation integral and rough integrals are given on the basis of function rough sets.Based on these concepts,the relation of the lower approximation integ... The concepts of the lower approximation integral,the upper approximation integral and rough integrals are given on the basis of function rough sets.Based on these concepts,the relation of the lower approximation integrals,the relation of the upper approximation integrals,the relation of rough integrals,and the double median theorem of rough integrals are discussed.Rough integrals have finite contraction characteristic and finite extension characteristic. 展开更多
关键词 function rough sets the lower approximation integral the upper approximation integral rough integrals
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Some Results of Upper and Lower <i>M</i>-Asymmetric Irresolute Multifunctions in Bitopological Spaces 被引量:1
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作者 Levy K. Matindih Edwin Moyo +1 位作者 Davy K. Manyika Timothy Sinyangwe 《Advances in Pure Mathematics》 2021年第6期611-627,共17页
In this paper, we aim to introduce and study some basic properties of upper and lower <em>M</em>-asymmetric irresolute multifunctions defined between asymmetric sets in the realm of bitopological spaces wi... In this paper, we aim to introduce and study some basic properties of upper and lower <em>M</em>-asymmetric irresolute multifunctions defined between asymmetric sets in the realm of bitopological spaces with certain minimal structures as a generalization of irresolute functions deal to Crossley and Hildebrand <a href="#ref1">[1]</a> and upper and lower irresolute Multifunctions deal to Popa <a href="#ref2">[2]</a>. 展开更多
关键词 TiTj-Semiopen sets M-Space M-Asymmetric Semiopen and Semiclosed sets upper (lower) Irresolute Multifunctions and upper (lower) M-Asymmetric Irresolute Multifunctions
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基于Rough sets和Fuzzy sets理论的约简算法
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作者 姚勇 王保义 李继荣 《微机发展》 2003年第7期97-100,共4页
对决策表约简的一些roughsets和fuzzysets相关概念进行了阐述。在应用Rough集对决策系统进行约简的基础上,结合模糊聚类分析方法,论述了这一可行的决策表约简算法。该算法以属性核与属性重要性的代数定义形式为基础,利用聚类分析的模糊... 对决策表约简的一些roughsets和fuzzysets相关概念进行了阐述。在应用Rough集对决策系统进行约简的基础上,结合模糊聚类分析方法,论述了这一可行的决策表约简算法。该算法以属性核与属性重要性的代数定义形式为基础,利用聚类分析的模糊处理方法,解决了约简过程。并给出了对一电器公司全国连锁销售数据约简处理结果,得出了能帮助不同级别决策者进行决策的辅助性的规则知识。 展开更多
关键词 Fuzzysets理论 Roughsets理论 约简算法 数据挖掘 数据库 集合论 知识发现
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Rough Sets in Approximate Solution Space
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作者 Hui Sun Wei Tian Qing Liu 《南昌工程学院学报》 CAS 2006年第2期70-73,共4页
As a new mathematical theory, Rough sets have been applied to processing imprecise, uncertain and incomplete data. It has been fruitful in finite and non-empty set. Rough sets, however, are only served as the theoreti... As a new mathematical theory, Rough sets have been applied to processing imprecise, uncertain and incomplete data. It has been fruitful in finite and non-empty set. Rough sets, however, are only served as the theoretic tool to discretize the real function. As far as the real function research is concerned, the research to define rough sets in the real function is infrequent. In this paper, we exploit a new method to extend the rough set in normed linear space, in which we establish a rough set,put forward an upper and lower approximation definition, and make a preliminary research on the property of the rough set.A new tool is provided to study the approximation solutions of differential equation and functional variation in normed linear space. This research is significant in that it extends the application of rough sets to a new field. 展开更多
关键词 rough sets approximate solution space upper and lower approximation
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二重积分及其应用
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作者 赵振刚 《首都师范大学学报(自然科学版)》 2024年第1期68-76,共9页
本文首先定义了矩形区域上的二重积分,并使用平行于x轴和y轴的直线网将矩形区域划分。对于相关性质,给出了详细、完整的证明,证明了在矩形区域上定义的有界函数可积的充要条件是该函数在矩形区域上的不连续点集是零测集。假设函数在矩... 本文首先定义了矩形区域上的二重积分,并使用平行于x轴和y轴的直线网将矩形区域划分。对于相关性质,给出了详细、完整的证明,证明了在矩形区域上定义的有界函数可积的充要条件是该函数在矩形区域上的不连续点集是零测集。假设函数在矩形区域上黎曼可积,成功地解决了固定变量x后,作为y的函数在相应闭区间上的黎曼积分未必存在的问题。其次,建立了有界函数在有界集上的积分,并将有界集上的积分转化为矩形区域上的积分。再次,介绍了二重积分的应用,证明了在开集上定义的二元函数的2个混合偏导数如果连续,则必然相等。最后,还使用二重积分证明了级数求和公式^(∞)∑=11/^(2)=π^(2)/6。 展开更多
关键词 上积分 下积分 零测集
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最小支配阈值集问题的降阶回溯算法
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作者 储旭 宁爱兵 +2 位作者 胡开元 代苏玉 张惠珍 《计算机工程与科学》 CSCD 北大核心 2024年第5期897-906,共10页
图论中的最小支配阈值集问题是组合优化中的一个NP-Hard问题,该问题是最小支配集问题的一个扩展问题。基于给定无向图G=(V,E)和阈值r的最小支配阈值集问题进行研究,首先得出一些可以降低问题规模的数学性质并证明,利用这些性质可以减小... 图论中的最小支配阈值集问题是组合优化中的一个NP-Hard问题,该问题是最小支配集问题的一个扩展问题。基于给定无向图G=(V,E)和阈值r的最小支配阈值集问题进行研究,首先得出一些可以降低问题规模的数学性质并证明,利用这些性质可以减小问题规模,降低问题的求解难度;然后设计出上界子算法、下界子算法和降阶子算法,并基于这些子算法提出了一种可以减小问题规模同时得到最优解的降阶回溯算法BAR;最后,通过一个示例分析和若干随机算例测试验证了降阶回溯算法可有效降低问题的求解难度。 展开更多
关键词 最小支配阈值集问题 数学性质 上下界算法 降阶回溯算法
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L-fuzzy集值映射的连续性 被引量:1
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作者 陈水利 《江汉石油学院学报》 EI CSCD 北大核心 2001年第1期75-78,共4页
在 L-fuzzy拓扑空间中引入 L-fuzzy上 (下 )拓扑、 L-fuzzy Vietoris拓扑、 L-fuzzy上 (下 )连续和L-fuzzy连续集值映射等概念。研究了这 3种 L-fuzzy拓扑的基本性质 ,给出 L-fuzzy集值映射的上连续性、下连续性和连续性的
关键词 L-fuzzy 拓扑 L-fuzzy集植映射 连续性
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L-Fuzzy强广义上(下)弱半连续多值映射及其性质
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作者 王小霞 姜金平 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第2期101-104,共4页
定义了广义开集和强广义开集.得出了有限个强广义开集之并仍是强广义开集,强广义开集一定是广义开集,强广义开集的内部是强广义开集.利用强广义开集引入强广义上(下)弱半连续多值映射等概念,讨论了其等价条件,并研究了它们的各种性质.
关键词 LF拓扑空间 LF多值映射 强广义开集 强广义上(下)弱半连续多值映射
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绿色闭环供应链网络解的存在性研究
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作者 徐嘉磊 林志 《科技和产业》 2024年第11期20-27,共8页
利用变分不等式相关知识对绿色闭环供应链网络均衡条件进行研究,构建各个决策者的可行策略的集值映射,将绿色闭环供应链网络均衡问题转化为广义Nash均衡问题,结合集值映射的连续性、凸性与紧性,利用不动点定理研究绿色闭环供应链网络解... 利用变分不等式相关知识对绿色闭环供应链网络均衡条件进行研究,构建各个决策者的可行策略的集值映射,将绿色闭环供应链网络均衡问题转化为广义Nash均衡问题,结合集值映射的连续性、凸性与紧性,利用不动点定理研究绿色闭环供应链网络解的存在性与均衡条件。基于研究结论,提出绿色闭环供应链网络各层决策者对应的变分不等式以及多准则网络均衡条件和绿色闭环供应链网络解的存在性定理。 展开更多
关键词 绿色闭环供应链 广义Nash均衡 集值映射 上半连续 下半连续 拟凹性
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A vague-set-based fuzzy multi-objective decision making model for bidding purchase 被引量:4
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作者 WANG Zhou-jing QIAN Edward Y. 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第4期644-650,共7页
A vague-set-based fuzzy multi-objective decision making model is developed for evaluating bidding plans in a bid- ding purchase process. A group of decision-makers (DMs) first independently assess bidding plans accord... A vague-set-based fuzzy multi-objective decision making model is developed for evaluating bidding plans in a bid- ding purchase process. A group of decision-makers (DMs) first independently assess bidding plans according to their experience and preferences, and these assessments may be expressed as linguistic terms, which are then converted to fuzzy numbers. The resulting decision matrices are then transformed to objective membership grade matrices. The lower bound of satisfaction and upper bound of dissatisfaction are used to determine each bidding plan’s supporting, opposing, and neutral objective sets, which together determine the vague value of a bidding plan. Finally, a score function is employed to rank all bidding plans. A new score function based on vague sets is introduced in the model and a novel method is presented for calculating the lower bound of sat- isfaction and upper bound of dissatisfaction. In a vague-set-based fuzzy multi-objective decision making model, different valua- tions for upper and lower bounds of satisfaction usually lead to distinct ranking results. Therefore, it is crucial to effectively contain DMs’ arbitrariness and subjectivity when these values are determined. 展开更多
关键词 Fuzzy multi-objective decision making model Vague set Score function lower bound of satisfaction upper bound of dissatisfaction
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On uniqueness of (fuzzy) relation in some generalized rough set model 被引量:1
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作者 PEI Dao-wu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2014年第3期253-264,共12页
In rough set theory, crisp and/or fuzzy binary relations play an important role in both constructive and axiomatic considerations of various generalized rough sets. This paper considers the uniqueness problem of the ... In rough set theory, crisp and/or fuzzy binary relations play an important role in both constructive and axiomatic considerations of various generalized rough sets. This paper considers the uniqueness problem of the (fuzzy) relation in some generalized rough set model. Our results show that by using the axiomatic approach, the (fuzzy) relation determined by (fuzzy) approximation operators is unique in some (fuzzy) double-universe model. 展开更多
关键词 fuzzy relation rough set fuzzy rough set lower approximation operator upper approximationoperator.
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Uncertainty Representation of Ocean Fronts Based on Fuzzy-Rough Set Theory
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作者 XUE Cunjin ZHOU Chenghu +1 位作者 SU Fenzhen ZHANG Dandan 《Journal of Ocean University of China》 SCIE CAS 2008年第2期131-136,共6页
Analysis of ocean fronts' uncertainties indicates that they result from indiscemibility of their spatial position and fuzziness of their intensity. In view of this, a flow hierarchy for uncertainty representation of ... Analysis of ocean fronts' uncertainties indicates that they result from indiscemibility of their spatial position and fuzziness of their intensity. In view of this, a flow hierarchy for uncertainty representation of ocean fronts is proposed on the basis of fuzzy-rough set theory. Firstly, raster scanning and blurring are carried out on an ocean front, and the upper and lower approximate sets, the indiscernible relation in fuzzy-rough theories and related operators in fuzzy set theories are adopted to represent its uncertainties, then they are classified into three sets: with members one hundred percent belonging to the ocean front, belonging to the ocean front's edge and definitely not belonging to the ocean front. Finally, the approximate precision and roughness degree are utilized to evaluate the ocean front's degree of uncertainties and the precision of the representation. It has been proven that the method is not only capable of representing ocean fronts' uncertainties, but also provides a new theory and method for uncertainty representation of other oceanic phenomena. 展开更多
关键词 fuzzy-rough set upper approximate sets lower approximate sets ocean fronts UNCERTAINTIES
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可调节多粒度粗糙集的细化与粗化
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作者 梁美社 谷怡欣 +1 位作者 米据生 靳晨霞 《人工智能科学与工程》 2023年第9期1-11,共11页
在经典的多粒度粗糙集模型中,属性值细化和粗化后的下近似、上近似变化并不明显,因此在处理实际问题时存在一定局限性。该文首先构造了属性值细化和粗化时的可调节多粒度粗糙集,讨论了可调节多粒度粗糙集下、上近似的一些性质,并设计了... 在经典的多粒度粗糙集模型中,属性值细化和粗化后的下近似、上近似变化并不明显,因此在处理实际问题时存在一定局限性。该文首先构造了属性值细化和粗化时的可调节多粒度粗糙集,讨论了可调节多粒度粗糙集下、上近似的一些性质,并设计了相应的增量算法。最后在实验部分中,通过调节数据集、属性集的大小对增量算法和原有的静态算法的计算时间进行比较。实验结果表明提出的可调节多粒度粗糙集在细化和粗化时的增量算法可以更加准确、高效地处理大型数据。 展开更多
关键词 多粒度 粗糙集 可调节多粒度粗糙集 增量算法 下近似 上近似
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一种新的基于粗糙集模型的决策树算法 被引量:16
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作者 高静 徐章艳 +1 位作者 宋威 杨炳儒 《计算机工程》 CAS CSCD 北大核心 2008年第3期9-11,共3页
在基于粗糙集模型的决策树生成算法中,由于分类的精确性,导致生成算法在对实例进行划分时往往过于细化,无法避免少数特殊实例对决策树造成的不良影响,使得生成的决策树过于庞大,不便于理解,同时也降低了其对未来数据的分类和预测能力。... 在基于粗糙集模型的决策树生成算法中,由于分类的精确性,导致生成算法在对实例进行划分时往往过于细化,无法避免少数特殊实例对决策树造成的不良影响,使得生成的决策树过于庞大,不便于理解,同时也降低了其对未来数据的分类和预测能力。针对上述问题,该文给出一个新的基于粗糙集模型的决策树生成算法,引入了抑制因子。对即将扩张的结点,除了常用的终止条件外,再加入一个终止条件:若样本的抑制因子大于给定的阈值,便不再扩展该结点。有效地避免了划分过细的问题,也不会生成过于庞大的决策树,便于用户理解。 展开更多
关键词 决策树 ID3算法 粗糙集 抑制因子 上近似集 下近似集
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粗糙集和拓扑空间 被引量:42
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作者 陈德刚 张文修 《西安交通大学学报》 EI CAS CSCD 北大核心 2001年第12期1313-1315,共3页
研究了粗糙集和拓扑空间的关系 ,讨论了Pawlak粗糙集模型的拓扑性质 ,指出Pawlak粗糙集模型等价于一类特殊的正则拓扑空间 ,该拓扑空间一般不是Hausdorff空间 ,且一般不具有连通性 .还证明了一个一般的二元关系下的粗糙集模型当且仅当... 研究了粗糙集和拓扑空间的关系 ,讨论了Pawlak粗糙集模型的拓扑性质 ,指出Pawlak粗糙集模型等价于一类特殊的正则拓扑空间 ,该拓扑空间一般不是Hausdorff空间 ,且一般不具有连通性 .还证明了一个一般的二元关系下的粗糙集模型当且仅当它是自反的和传递的时 ,可定义一个拓扑空间 。 展开更多
关键词 粗糙集 拓扑空间 上近似 下近似 Pawlak粗糙集模型 近似空间 拓扑学
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Rough集理论:现状与前景 被引量:34
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作者 刘清 黄兆华 姚力文 《计算机科学》 CSCD 北大核心 1997年第4期1-5,共5页
经典逻辑中只有真、假二值,但实际上有大盆含糊现象存在于宾和假二值之间,因此,长以来许多逻辑学家和哲学家就致力于研究含糊概念。早在1904年谓词逻辑的创始人G.
关键词 ROUGH集理论 计算机理论 人工智能
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区间数排序的粗糙集方法 被引量:17
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作者 刘学生 吴伟 邹开其 《大连理工大学学报》 CAS CSCD 北大核心 2008年第1期143-146,共4页
针对模糊多属性决策中属性值为区间数情况下区间数排序问题,应用粗糙集理论和模糊集理论得到了一种区间数的排序方法:区间数上近似集排序法;区间数下近似集排序法;区间数上(下)近似集折中排序方法.给出了区间数的粗糙集表示,区间数的粗... 针对模糊多属性决策中属性值为区间数情况下区间数排序问题,应用粗糙集理论和模糊集理论得到了一种区间数的排序方法:区间数上近似集排序法;区间数下近似集排序法;区间数上(下)近似集折中排序方法.给出了区间数的粗糙集表示,区间数的粗糙集排序方法及其良好性质.详细论证了其与经典的区间数排序的可能度方法相比的诸多优势.同时给出了具体实例并进行了这种方法的应用与验证,以便能更好地理解这种粗糙集排序方法. 展开更多
关键词 粗糙集 区间数排序 上(下)近似集
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