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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 Results on the Upper Convex Densities of the Self-Similar Sets at the Contracting-Similarity Fixed Points
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作者 Shaoyuan Xu Wangbin Xu Zuoling Zhou 《Analysis in Theory and Applications》 CSCD 2015年第1期92-100,共9页
In this paper, some results on the upper convex densities of self-similar sets at the contracting-similarity fixed points are discussed. Firstly, a characterization of the upper convex densities of self-similar sets a... In this paper, some results on the upper convex densities of self-similar sets at the contracting-similarity fixed points are discussed. Firstly, a characterization of the upper convex densities of self-similar sets at the contracting-similarity fixed points is given. Next, under the strong separation open set condition, the existence of the best shape for the upper convex densities of self-similar sets at the contracting-similarity fixed points is proven. As consequences, an open problem and a conjecture, which were posed by Zhou and Xu, are answered. 展开更多
关键词 Self-similar set upper convex density Hausdorff measure and Hausdorff dimension contracting-similarity fixed point.
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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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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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上扬子南缘五峰组——龙马溪组页岩地球化学特征及其对风化、物源与构造背景的指示
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作者 秦何星 陈雷 +6 位作者 卢畅 胡月 熊敏 谭秀成 计玉冰 陈鑫 王高翔 《地质论评》 CAS CSCD 北大核心 2024年第4期1314-1334,共21页
为深入探讨上扬子地区南缘晚奥陶世—早志留世黑色页岩的物质来源、风化作用和源区构造背景,本文选取典型野外剖面,对五峰组—龙马溪组页岩主量、微量和稀土元素地球化学特征进行系统研究并探讨其地质意义。结果显示:上扬子南缘五峰组... 为深入探讨上扬子地区南缘晚奥陶世—早志留世黑色页岩的物质来源、风化作用和源区构造背景,本文选取典型野外剖面,对五峰组—龙马溪组页岩主量、微量和稀土元素地球化学特征进行系统研究并探讨其地质意义。结果显示:上扬子南缘五峰组—龙马溪组黑色富有机质页岩具有与上地壳相似的贫高场强元素、富集大离子亲石元素特征,∑REE值(103.66×10^(-6)~295.98×10^(-6),平均180.57×10^(-6))整体较高,稀土元素标准化配分模式与上地壳极为相似,呈现“V”型向右倾斜、轻稀土元素富集、重稀土元素平坦、轻重稀土分异明显、Eu负异常明显的特征;特征微量、稀土元素含量及比值,如:La、Ce、La/Yb、Sc/Cr,均表现出与被动大陆边缘特征值相接近;样品成分变异指数ICV值(0.55~14.1,平均2.28)和Zr/Sc—Th/Sc图解指示物源为构造带首次快速沉积产物,不具备沉积再循环特征;较低的CIA值(54.89~71.61,平均65.27)、A—CN—K图解和K_(2)O/Al_(2)O_(3)—Ga/Rb图解表明物源受化学风化作用较小,沉积环境为寒冷、干燥环境;K_(2)O、Rb、Al_(2)O_(3)/TiO_(2)含量较高及Eu负异常指示其源岩以长英质火成岩及花岗岩类的偏酸性地质体为主;综合物源、构造背景判别图解,推断上扬子南缘五峰组—龙马溪组页岩主体形成于被动大陆边缘,物源主要来自于西侧康滇古陆新元古代早期地台盖层,黔中隆起次之,伴随扬子板块东南部中酸性火山物质涌入沉积。 展开更多
关键词 五峰组—龙马溪组 地球化学 风化作用 物源 构造背景 上扬子南缘
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基于Rough Set的中医类风湿诊断知识抽取 被引量:1
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作者 秦中广 毛宗源 邓兆智 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2000年第4期30-34,共5页
提出了基于RoughSet理论用于类风湿的中医辨证 .首先介绍了RoughSet的基本概念 ,并给出了处理类风湿中医辨证的处理方法 .实践表明 。
关键词 中医 类风湿诊断 中医辨证
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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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一类高维齐次Moran集的Hausdorff维数与上盒维数
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作者 安成帅 李俊 李彦哲 《应用数学》 北大核心 2024年第2期456-465,共10页
本文构造一类特殊的高维齐次Moran集:{m_(k)^(d)}型齐次Moran集,并得到了满足一定条件的这类集合的Hausdorff维数与上盒维数的表达式.
关键词 {m_(k)^(d)}型齐次Moran集 HAUSDORFF维数 上盒维数
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《无铬鞣鞋面用皮革》行业标准解读
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作者 步巧巧 桑军 +2 位作者 王华佳 董慧峰 任可帅 《中国皮革》 CAS 2024年第6期37-43,共7页
QB/T 5796—2023《无铬鞣鞋面用皮革》为我国首个关于无铬鞣技术的产品标准。本文主要从标准的适用范围、技术要求、试验方法、检验规则以及标志、包装、运输和贮存等方面进行了详细解读。重点阐述了标准的制定背景、主要内容和技术要... QB/T 5796—2023《无铬鞣鞋面用皮革》为我国首个关于无铬鞣技术的产品标准。本文主要从标准的适用范围、技术要求、试验方法、检验规则以及标志、包装、运输和贮存等方面进行了详细解读。重点阐述了标准的制定背景、主要内容和技术要求的确定依据等;通过与铬鞣鞋面用皮革的对比分析,以期各相关方更加深入地了解标准内涵、统一认识、执行《无铬鞣鞋面用皮革》行业标准,为国内相关检测机构和生产企业正确理解和运用标准、准确判定产品质量提供指导。 展开更多
关键词 QB/T 5796—2023 制定背景 无铬鞣 鞋面革 技术要求
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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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中医辩证护理联合目标设定流程化健康宣教在急性上消化道出血患者中的应用研究
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作者 贾俊利 刘建华 《临床研究》 2024年第7期148-151,共4页
目的探究中医辩证护理联合目标设定流程化健康宣教在急性上消化道出血(UGIB)患者中的应用研究。方法选取2021年1月至2023年1月濮阳市中医医院肝胆脾胃科收治的100例急性UGIB患者作为研究对象,采用随机分层化法将其分为对照组(n=50)和观... 目的探究中医辩证护理联合目标设定流程化健康宣教在急性上消化道出血(UGIB)患者中的应用研究。方法选取2021年1月至2023年1月濮阳市中医医院肝胆脾胃科收治的100例急性UGIB患者作为研究对象,采用随机分层化法将其分为对照组(n=50)和观察组(n=50)。对照组给予常规护理,观察组在对照组的基础上采取中医辩证护理联合目标设定流程化健康宣教的模式进行干预,干预7 d,出院后进行随访2个月。比较两组患者恢复情况及不良情况发生率,比较干预前、干预7 d后两组患者心理状态[中国成年人心理弹性量表(RSA)]、生活质量[生活质量指数问卷(QL-Index)]差异。结果观察组患者止血时间、首次进食时间、黑便转黄时间及平均住院时间均低于对照组,差异有统计学意义(P<0.05)。观察组不良反应发生率(14.00%)低于对照组(34.00%),差异有统计学意义(P<0.05);干预后,两组患者RSA、QL-Index评分均高于干预前,且观察组上述评分高于对照组,差异有统计学意义(P<0.05)。结论采取中医辩证护理联合目标设定流程化健康宣教的模式对急性UGIB患者进行干预后,有效缩短患者恢复时间,改善患者心理状态及生活质量,并可提高安全性。 展开更多
关键词 中医辩证护理 目标设定流程化 健康宣教 急性上消化道出血
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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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A Negative Answer to a Conjecture on Upper Convex Density 被引量:1
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作者 尹建东 《Northeastern Mathematical Journal》 CSCD 2008年第5期386-394,共9页
Let E be a self-similar set satisfying the open set condition. Professor Xu conjectures in his doctoral degree thesis that if H^8(E) 〈|E|^8, then for any x ∈ E, the inequality ^-D^3C(E,x)〉H^8(E)/|E|^8hold... Let E be a self-similar set satisfying the open set condition. Professor Xu conjectures in his doctoral degree thesis that if H^8(E) 〈|E|^8, then for any x ∈ E, the inequality ^-D^3C(E,x)〉H^8(E)/|E|^8holds, where 3 = dimH(E). The above conjecture is negatively answered in this'paper. 展开更多
关键词 Hausdorg dimension Hausdorff measure upper convex density open set condition contracting-similarity fixed point
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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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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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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 投标购买 模糊多目标决策模型 模糊集 评价
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ELEMENTARY DENSITY BOUNDS FOR SELF-SIMILAR SETS AND APPLICATION 被引量:1
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作者 Shaoyuan Xu Weiyi Su 《Analysis in Theory and Applications》 2007年第4期334-342,共9页
Falconer[1] used the relationship between upper convex density and upper spherical density to obtain elementary density bounds for s-sets at H S-almost all points of the sets. In this paper, following Falconer[1], we ... Falconer[1] used the relationship between upper convex density and upper spherical density to obtain elementary density bounds for s-sets at H S-almost all points of the sets. In this paper, following Falconer[1], we first provide a basic method to estimate the lower bounds of these two classes of set densities for the self-similar s-sets satisfying the open set condition (OSC), and then obtain elementary density bounds for such fractals at all of their points. In addition, we apply the main results to the famous classical fractals and get some new density bounds. 展开更多
关键词 self-similar s-set upper convex density upper spherical density Hausdorff measure elementary density bound
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SET VALUE MAPPING AND ITS APPLICATION
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作者 李挺 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第2期263-268,共6页
The dynamics of set value mapping is considered. For the upper semi-continuous set value maps, the existence of attractors under some conditions and the upper semi-continuity of attractors under the perturbation are p... The dynamics of set value mapping is considered. For the upper semi-continuous set value maps, the existence of attractors under some conditions and the upper semi-continuity of attractors under the perturbation are proved. Its application in numerical simulation of differential equation is also considered. The upper semi-continuity of attractors in set value maps under the perturbation is used to show the reasonable of subdivision algorithm and interval arithmetic in numerical simulation of differential equation. 展开更多
关键词 set value mapping ATTRACTOR upper semi-continuity
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Random attractors for asymptotically upper semicompact multivalue random semiflows
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作者 李挺 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第11期1527-1534,共8页
The present paper studied the dynamics of some multivalued random semiflow. The corresponding concept of random attractor for this case was introduced to study asymptotic behavior. The existence of random attractor of... The present paper studied the dynamics of some multivalued random semiflow. The corresponding concept of random attractor for this case was introduced to study asymptotic behavior. The existence of random attractor of multivalued random semiflow was proved under the assumption of pullback asymptotically upper semicompact, and this random attractor is random compact and invariant. Furthermore, if the system has ergodicity, then this random attractor is the limit set of a deterministic bounded set. 展开更多
关键词 random attractor asymptotically upper semicompact absorbing set
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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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