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基于三维曲面Spline模型研究中国不同地区的磁场分布
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作者 冯彦 黄娅 +2 位作者 李翊君 张晋源 刘爽 《Applied Geophysics》 SCIE CSCD 2024年第1期31-40,203,共11页
利用地面台站以及子午工程测点,CHAMP卫星实测数据,建立了中国地区主磁场的三维曲面Spline(3DSS)模型。基于该模型进行了我国的高原地区(青藏高原28°N-38°N,78°E-102°E)、平原地区(长江中下游平原27°N-34°... 利用地面台站以及子午工程测点,CHAMP卫星实测数据,建立了中国地区主磁场的三维曲面Spline(3DSS)模型。基于该模型进行了我国的高原地区(青藏高原28°N-38°N,78°E-102°E)、平原地区(长江中下游平原27°N-34°N,111°E-122°E)以及海洋地区(东海和南海部分区域16°N-30°N,123°E-136°E)的磁场模拟。分别基于高原及平原的实测数据建立了各自的3DSS模型。另外分别建立了对应的二维Taylor(2DTY)、三维Taylor多项式(3DTY)模型以比较验证。建模时考虑了所有测点的场源移除、地面及卫星数据间的数据真空、边界效应等问题。为了考察模型相对于实测值的模拟精度,对三个地区分别选取若干个测点不参与建模,将所建模型分别模拟这些测点,并计算残差、变化率及均方根偏差(RMSE)。结果显示无论是全国3DSS模型还是小区域3DSS模型,其变化率除了Y分量略大,其余分量都在1%以内,模拟精度均要好于2DTY和3DTY模型。小区域(高原及平原)3DSS模型能较好反映区域磁场分布。模型对高原的拟合最好,平原次之,海洋地区最差,说明3DSS模型不需要太多的测点即可完成建模,但建模精度依赖于测点的数量及分布。 展开更多
关键词 地磁场 三维模型 曲面spline 子午工程 CHAMP卫星 CM4
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B-Spline曲线聚风装置直线翼垂直轴风力机启动性能数值模拟
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作者 李岩 马云飞 +2 位作者 佟国强 杨胜兵 肖振军 《排灌机械工程学报》 CSCD 北大核心 2024年第3期265-272,共8页
为了提升直线翼垂直轴风力机的启动性能,基于B-Spline曲线生成方法,提出一种具有流线型轮廓的聚风装置,将其分别安装在风轮顶端和底端,用以提升风轮附近的来流风速,使风轮汲取更多风能,达到更易启动的特点.选取聚风装置的5个结构参数进... 为了提升直线翼垂直轴风力机的启动性能,基于B-Spline曲线生成方法,提出一种具有流线型轮廓的聚风装置,将其分别安装在风轮顶端和底端,用以提升风轮附近的来流风速,使风轮汲取更多风能,达到更易启动的特点.选取聚风装置的5个结构参数进行设计:聚风装置与风轮间隙距离ΔL、底圆半径R_(1)、顶圆半径R_(2)、入口角度α_(1)和出口角度α_(2).设计方法采用二次旋转正交组合筛选最优模型,通过三维数值模拟研究聚风装置参数对直线翼垂直轴风力机启动性能的影响,获得了最佳外形参数组合.此外,对有无加装聚风装置的直线翼垂直轴风力机进行了静态三维数值模拟.结果表明,通过添加具有外凸流线型轮廓的聚风装置,直线翼垂直轴风力机的启动性能有显著提升.在风速较低的情况下,性能改善更加明显.聚风装置可使直线翼垂直轴风力机的平均启动力矩系数最大增加38.8%,峰值平均启动力矩系数最大可增加31.2%. 展开更多
关键词 垂直轴风力机 聚风装置 B-spline曲线 启动性能 数值模拟
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基于Spline算法经编间隔织物的仿真建模
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作者 王文 邓中民 +1 位作者 李娟 柯薇 《针织工业》 北大核心 2024年第2期17-20,共4页
现阶段大多建模方法得到的模型保形性差,且缺少光照处理。文章提出一种基于Spline插值算法的建模方法,该方法保证曲线经过所有控制点,在三维空间上建立与实际织物基本相同的空间曲线,解决了以往所得模型保形性差的问题,并且通过VC++以及... 现阶段大多建模方法得到的模型保形性差,且缺少光照处理。文章提出一种基于Spline插值算法的建模方法,该方法保证曲线经过所有控制点,在三维空间上建立与实际织物基本相同的空间曲线,解决了以往所得模型保形性差的问题,并且通过VC++以及OpenGL开发工具,可以加上环境光照渲染、纹理处理等,使仿真模型更为写实,得到的仿真模型可以节省人力和物力及时间,能够在短时间内为设计人员提供更为准确的设计思路和方案。 展开更多
关键词 经编间隔织物 spline算法 OPENGL 仿真建模 保形性
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基于B-spline的路径规划与轨迹跟踪研究
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作者 庞同嘉 王金波 田宇洋 《农业装备与车辆工程》 2024年第7期50-55,61,共7页
为满足局部路径规划换道路径下的特性和提高智能驾驶车辆在多种变曲率条件下的路径跟踪精度和稳定性,采用贝塞尔曲线、B-spline等路径规划换道条件下的方法,分别在圆形轨迹、8字形轨迹、S形轨迹、正弦曲线形轨迹路径下,基于MATLAB对4类... 为满足局部路径规划换道路径下的特性和提高智能驾驶车辆在多种变曲率条件下的路径跟踪精度和稳定性,采用贝塞尔曲线、B-spline等路径规划换道条件下的方法,分别在圆形轨迹、8字形轨迹、S形轨迹、正弦曲线形轨迹路径下,基于MATLAB对4类路径跟踪算法进行分析,得出最合理的B-spline路径规划和跟踪算法。结果表明,B-spline算法在换道点和并道点曲率为0,满足换道条件的要求;MPC算法在正弦轨迹下比其他算法平均误差小约48.6%,在圆形轨迹下比其他算法平均误差小约84%,说明该算法在多种轨迹下都具有很好的跟踪性,能在一定程度上保证智能驾驶汽车的安全性和稳定性,为今后智能车辆路径规划和轨迹跟踪控制研究提供参考。 展开更多
关键词 智能驾驶 轨迹跟踪 B-spline 稳定性
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用于超精密抛光机床的Spline+GLS定位误差补偿模型 被引量:2
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作者 潘海鸿 喻洪基 +2 位作者 陈旭红 陈琳 梁旭斌 《组合机床与自动化加工技术》 北大核心 2023年第5期156-159,163,共5页
针对三次样条插值定位误差补偿模型难达到超精密抛光机床大行程轴(1470 mm)的定位误差补偿精度要求问题,提出Spline+GLS定位误差补偿模型。首先,使用XL-80激光干涉仪测量超精密抛光机床直线电机轴的定位误差,建立三次样条插值定位误差... 针对三次样条插值定位误差补偿模型难达到超精密抛光机床大行程轴(1470 mm)的定位误差补偿精度要求问题,提出Spline+GLS定位误差补偿模型。首先,使用XL-80激光干涉仪测量超精密抛光机床直线电机轴的定位误差,建立三次样条插值定位误差补偿模型进行初补偿;然后,对补偿后的定位误差再次测量并建立最小二乘拟合定位误差补偿模型;最后,将两种定位误差补偿模型相连构成Spline+GLS定位误差补偿模型。在超精密抛光机床上进行补偿实验,结果表明,Spline+GLS定位误差补偿模型补偿后的最大定位偏差值较三次样条插值定位误差补偿模型下降约61.62%,且定位误差由86.12μm降低到0.5μm,满足超精密抛光机床的定位精度需求。 展开更多
关键词 超精密抛光机床 定位误差补偿 spline插值 GLS拟合
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CONE-DIRECTED CONTINGENT DERIVATIVES AND GENERALIZED PREINVEX SET-VALUED OPTIMIZATION 被引量:10
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作者 丘京辉 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期211-218,共8页
By using cone-directed contingent derivatives, the unified necessary and sufficient optimality conditions are given for weakly and strongly minimal elements respectively in generalized preinvex set-valued optimization.
关键词 Preinvex set-valued optimization cone-directed contingent derivative optimality conditions
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THE OPTIMALITY CONDITIONS OF NONCONVEXSET-VALUED VECTOR OPTIMIZATION 被引量:2
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作者 盛保怀 刘三阳 《Acta Mathematica Scientia》 SCIE CSCD 2002年第1期47-55,共9页
The concepts of alpha-order Clarke's derivative, alpha-order Adjacent derivative and alpha-order G.Bouligand derivative of set-valued mappings are introduced, their properties are studied, with which the Fritz Joh... The concepts of alpha-order Clarke's derivative, alpha-order Adjacent derivative and alpha-order G.Bouligand derivative of set-valued mappings are introduced, their properties are studied, with which the Fritz John optimality condition of set-valued vector optimization is established. Finally, under the assumption of pseudoconvexity, the optimality condition is proved to be sufficient. 展开更多
关键词 set-valued derivative optimality condition pseudoconvex set-valued mapping
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On super efficiency in set-valued optimization 被引量:3
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作者 LI Tai-yong XU Yi-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第2期144-150,共7页
The set-valued optimization problem with constraints is considered in the sense of super efficiency in locally convex linear topological spaces. Under the assumption of iccone-convexlikeness, by applying the seperatio... The set-valued optimization problem with constraints is considered in the sense of super efficiency in locally convex linear topological spaces. Under the assumption of iccone-convexlikeness, by applying the seperation theorem, Kuhn-Tucker's, Lagrange's and saddle points optimality conditions, the necessary conditions are obtained for the set-valued optimization problem to attain its super efficient solutions. Also, the sufficient conditions for Kuhn-Tucker's, Lagrange's and saddle points optimality conditions are derived. 展开更多
关键词 super efficiency IC-CONE-CONVEXLIKENESS set-valued optimization saddle point
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ON THE GENERALIZED FRITZ JOHN OPTIMALITY CONDITIONS OF VECTOR OPTIMIZATION WITH SET-VALUED MAPS UNDER BENSON PROPER EFFICIENCY 被引量:3
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作者 盛宝怀 刘三阳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第12期1444-1451,共8页
A kind of tangent derivative and the concepts of strong and weak * pseudoconvexity for a set-valued map are introduced. By the standard separation theorems of the convex sets and cones the optimality Fritz John condit... A kind of tangent derivative and the concepts of strong and weak * pseudoconvexity for a set-valued map are introduced. By the standard separation theorems of the convex sets and cones the optimality Fritz John condition of set-valued optimization under Benson proper efficiency is established, its sufficience is discussed. The form of the optimality conditions obtained here completely tally with the classical results when the set-valued map is specialized to be a single-valued map. 展开更多
关键词 contingent tangent cone set-valued map Benson proper efficiency Fritz John condition
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KUHN-TUCKER CONDITION AND WOLFE DUALITY OF PREINVEX SET-VALUED OPTIMIZATION 被引量:2
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作者 盛宝怀 刘三阳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第12期1655-1664,共10页
The optimality Kuhn-Tucker condition and the wolfe duality for the preinvex set-valued optimization are investigated. Firstly, the concepts of alpha-order G-invex set and the alpha-order S-preinvex set-valued function... The optimality Kuhn-Tucker condition and the wolfe duality for the preinvex set-valued optimization are investigated. Firstly, the concepts of alpha-order G-invex set and the alpha-order S-preinvex set-valued function were introduced, from which the properties of the corresponding contingent cone and the alpha-order contingent derivative were studied. Finally, the optimality Kuhn-Tucker condition and the Wolfe duality theorem for the alpha-order S-preinvex set-valued optimization were presented with the help of the alpha-order contingent derivative. 展开更多
关键词 preinvex set-valued function contingent epiderivatives optimality conditions DUALITY
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基于二维B-splines方法研究强磁场中类氢离子He+的低能能级
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作者 刘凤丽 《黑龙江大学自然科学学报》 2023年第5期596-604,共9页
采用改进的二维B-spline方法在柱坐标系下研究了强磁场下类氢离子He^(+)的结构和电子空间几率密度,计算包含三种对称性0^(+)、0^(-)和(^(-)1)^(+)共10个本征态1 0^(+)、2 0^(+)、ν 0^(-)(ν=1~4)和ν(-1)^(+)(ν=1~4)的能级,选定磁感... 采用改进的二维B-spline方法在柱坐标系下研究了强磁场下类氢离子He^(+)的结构和电子空间几率密度,计算包含三种对称性0^(+)、0^(-)和(^(-)1)^(+)共10个本征态1 0^(+)、2 0^(+)、ν 0^(-)(ν=1~4)和ν(-1)^(+)(ν=1~4)的能级,选定磁感应强度分别为0、0.001、0.003、0.005、0.007、0.010、0.030、0.050、0.070、0.100、0.200、0.300、0.500、0.700和1.000 a.u.。计算结果表明,类氢离子He^(+)的能级在强磁场中发生劈裂,简并度消除,得到了各个能级随磁感应强度变化规律,并且发现随着磁感应强度的增加能级高低会改变,甚至会发生能级翻转现象;定量地研究了类氢离子He^(+)的基态1 0^(+)和激发态3 0^(-)几率密度分布随磁感应强度的变化规律,并与氢原子进行比较。本研究部分计算结果与他人研究结果十分吻合,有助于进一步理解其他复杂原子的电子运动行为。 展开更多
关键词 B-spline方法 类氢离子He+ 强磁场 能级
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EKELAND'S PRINCIPLE FOR SET-VALUED VECTOR EQUILIBRIUM PROBLEMS 被引量:3
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作者 龚循华 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1179-1192,共14页
In this paper, we introduce a concept of quasi C-lower semicontinuity for setvalued mapping and provide a vector version of Ekeland's theorem related to set-valued vector equilibrium problems. As applications, we der... In this paper, we introduce a concept of quasi C-lower semicontinuity for setvalued mapping and provide a vector version of Ekeland's theorem related to set-valued vector equilibrium problems. As applications, we derive an existence theorem of weakly efficient solution for set-valued vector equilibrium problems without the assumption of convexity of the constraint set and the assumptions of convexity and monotonicity of the set-valued mapping. We also obtain an existence theorem of ε-approximate solution for set-valued vector equilibrium problems without the assumptions of compactness and convexity of the constraint set. 展开更多
关键词 Ekeland's principle set-valued vector equilibrium problems weakly efficient solution c-approximate solution EXISTENCE
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Benson proper efficiency for vector optimization of generalized subconvexlike set-valued maps in ordered linear spaces 被引量:2
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作者 周志昂 《Journal of Shanghai University(English Edition)》 CAS 2010年第5期374-379,共6页
Several equivalent statements of generalized subconvexlike set-valued map are established in ordered linear spaces. Using vector closure, we introduce Benson proper efficient solution of vector optimization problem. U... Several equivalent statements of generalized subconvexlike set-valued map are established in ordered linear spaces. Using vector closure, we introduce Benson proper efficient solution of vector optimization problem. Under the assumption of generalized subconvexlikeness, scalarization, multiplier and saddle point theorems are obtained in the sense of Benson proper efficiency. 展开更多
关键词 set-valued maps vector closure generalized subconvexlikeness Benson proper efficient solution
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Some Dynamical Properties in Set-valued Discrete Systems 被引量:2
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作者 马先峰 廖公夫 李勇 《Northeastern Mathematical Journal》 CSCD 2005年第1期5-8,共4页
1 Introduction A discrete dynamical system can be expressed as xn+1 ?f(xn), n = 0,1,2,... where X is a metric space and f : X →X is a continuous map. The study of it tells us how the points in the base space X moved.... 1 Introduction A discrete dynamical system can be expressed as xn+1 ?f(xn), n = 0,1,2,... where X is a metric space and f : X →X is a continuous map. The study of it tells us how the points in the base space X moved. Nevertheless, this is not enough for the researches of biological species, demography, numerical simulation and attractors (see [1], [2]). It is necessary to know how the subsets of X moved. In this direction, we consider the set-valued discrete system associated to f, An+1 = (f|-)(An), n = 0,1,2,... where (f|-) is the natural extension of f to K(X) (the class of all compact subsets of X). 展开更多
关键词 set-valued discrete system MINIMALITY topologically weak mixing topo-logical mixing
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Auxiliary principle and three-step iterative algorithms for generalized set-valued strongly nonlinear mixed variational-like inequalities 被引量:1
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作者 徐海丽 郭兴明 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第6期721-729,共9页
An auxiliary principle technique to study a class of generalized set-valued strongly nonlinear mixed variational-like inequalities is extended. The existence and uniqueness of the solution of the auxiliary problem for... An auxiliary principle technique to study a class of generalized set-valued strongly nonlinear mixed variational-like inequalities is extended. The existence and uniqueness of the solution of the auxiliary problem for the generalized set-valued strongly nonlinear mixed variational-like inequalities are proved, a novel and innovative three-step iterative algorithm to compute approximate solution is constructed, and the existence of the solution of the generalized set-valued strongly nonlinear mixed variational-like inequality is shown using the auxiliary principle iterative sequences generated by the algorithm technique. The convergence of three-step is also proved. 展开更多
关键词 mixed variational-like inequality three-step iterative algorithm set-valued mapping auxiliary principle technique
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ε-super Effcient Solutions of Optimization Problems with Set-valued Maps in Locally Convex Space 被引量:1
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作者 WANG Shu-yu LIU Wan-li 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第1期26-31,共6页
In this paper,the ε-super effcient solution for set-valued map vector optimization in locally convex space is introduced.And under the assumption of the nearly generalized cone-subconvexlikeness for set-valued maps,u... In this paper,the ε-super effcient solution for set-valued map vector optimization in locally convex space is introduced.And under the assumption of the nearly generalized cone-subconvexlikeness for set-valued maps,used new methods,the scalarization theorem and Lagrange multiplier theorem for ε-super effcient solution are established. 展开更多
关键词 nearly generalized cone-subconvexlikeness set-valued map ε-super effcient solution lagrange multiplier
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Monotone Set-Valued Function Defined by Set-Valued Choquet Integral
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作者 孙红霞 张强 《Journal of Beijing Institute of Technology》 EI CAS 2010年第2期241-245,共5页
Structural characteristics and absolute continuities of monotone set-valued function defined by set- valued Choquet integral are discussed. Similar to the single-valued monotone set function, several important structu... Structural characteristics and absolute continuities of monotone set-valued function defined by set- valued Choquet integral are discussed. Similar to the single-valued monotone set function, several important structural characteristics of set-valued function are defined and have been proven the same as those in the original set functions, such as null-additivity, weakly null-additivity, order continuity, strong order continuity and property(S). A counterexample shows that order continuity and strong order continuity of the original set functions are no longer kept in a monotone set-valued function when Choquet integrably bounded assumption is abandoned. Four kinds of absolute continuities are defined for set-valued function, and all been proven valid with respect to the original set functions. 展开更多
关键词 monotone set-valued function set-valued Choquet integral Choquet integral
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ANALYSIS OF SYSTEM QUALITY BY SET-VALUED STATISTICS
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作者 黄洪钟 胡宗武 吴杰明 《Journal of Shanghai Jiaotong university(Science)》 EI 1998年第1期54-58,共5页
ANALYSISOFSYSTEMQUALITYBYSET┐VALUEDSTATISTICS*HuangHongzhong(黄洪钟)HuZongwu(胡宗武)(Dept.ofMechanicalEngineering,... ANALYSISOFSYSTEMQUALITYBYSET┐VALUEDSTATISTICS*HuangHongzhong(黄洪钟)HuZongwu(胡宗武)(Dept.ofMechanicalEngineering,ShanghaiJiaotongU... 展开更多
关键词 洪钟 OF BY QUALITY set-valued SYSTEM 胡宗武 ANALYSIS
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ON SELECTIONS OF SET-VALUED EULER-LAGRANGE INCLUSIONS WITH APPLICATIONS
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作者 Hamid KHODAEI Iz-iddine EL-FASSI Bahman HAYAT 《Acta Mathematica Scientia》 SCIE CSCD 2020年第4期1105-1115,共11页
We discuss the set-valued dynamics related to the theory of functional equations.We look for selections of convex set-valued functions satisfying set-valued Euler-Lagrange inclusions.We improve and extend upon some of... We discuss the set-valued dynamics related to the theory of functional equations.We look for selections of convex set-valued functions satisfying set-valued Euler-Lagrange inclusions.We improve and extend upon some of the results in[13,20],but under weaker assumptions.Some applications of our results are also provided. 展开更多
关键词 set-valued dynamics Euler-Lagrange inclusion composite operator SELECTION
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Attribute Reduction in Interval and Set-Valued Decision Information Systems
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作者 Hong Wang Hong-Bo Yue Xi-E Chen 《Applied Mathematics》 2013年第11期1512-1519,共8页
In many practical situation, some of the attribute values for an object may be interval and set-valued. This paper introduces the interval and set-valued information systems and decision systems. According to the sema... In many practical situation, some of the attribute values for an object may be interval and set-valued. This paper introduces the interval and set-valued information systems and decision systems. According to the semantic relation of attribute values, interval and set-valued information systems can be classified into two categories: disjunctive (Type 1) and conjunctive (Type 2) systems. In this paper, we mainly focus on semantic interpretation of Type 1. Then, we define a new fuzzy preference relation and construct a fuzzy rough set model for interval and set-valued information systems. Moreover, based on the new fuzzy preference relation, the concepts of the significance measure of condition attributes and the relative significance measure of condition attributes are given in interval and set-valued decision information systems by the introduction of fuzzy positive region and the dependency degree. And on this basis, a heuristic algorithm for calculating fuzzy positive region reduction in interval and set-valued decision information systems is given. Finally, we give an illustrative example to substantiate the theoretical arguments. The results will help us to gain much more insights into the meaning of fuzzy rough set theory. Furthermore, it has provided a new perspective to study the attribute reduction problem in decision systems. 展开更多
关键词 INTERVAL and set-valued INFORMATION SYSTEMS FUZZY Preference Relation INTERVAL and set-valued DECISION INFORMATION SYSTEMS FUZZY Positive Region Dependency Degree Significance Measure
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