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Voltage-dependent plasticity and image Boolean operations realized in a WOx-based memristive synapse 被引量:1
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作者 Jiajuan Shi Ya Lin +4 位作者 Tao Zeng Zhongqiang Wang Xiaoning Zhao Haiyang Xu Yichun Liu 《Journal of Semiconductors》 EI CAS CSCD 2021年第1期128-133,共6页
The development of electronic devices that possess the functionality of biological synapses is a crucial step towards neuromorphic computing.In this work,we present a WOx-based memristive device that can emulate volta... The development of electronic devices that possess the functionality of biological synapses is a crucial step towards neuromorphic computing.In this work,we present a WOx-based memristive device that can emulate voltage-dependent synaptic plasticity.By adjusting the amplitude of the applied voltage,we were able to reproduce short-term plasticity(STP)and the transition from STP to long-term potentiation.The stimulation with high intensity induced long-term enhancement of conductance without any decay process,thus representing a permanent memory behavior.Moreover,the image Boolean operations(including intersection,subtraction,and union)were also demonstrated in the memristive synapse array based on the above voltage-dependent plasticity.The experimental achievements of this study provide a new insight into the successful mimicry of essential characteristics of synaptic behaviors. 展开更多
关键词 MEMRISTOR artificial synapse short-term plasticity long-term potentiation image boolean operations
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Boolean operations of STL models based on edge-facet intersection 被引量:1
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作者 郭开波 张李超 +1 位作者 王从军 黄树槐 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第5期711-717,共7页
For the data processing of the Rapid Prototyping Manufacturing, Boolean operation can offer a versatile tool for editing or modifying the STL model, adding the artificial construction, and creating the complex assista... For the data processing of the Rapid Prototyping Manufacturing, Boolean operation can offer a versatile tool for editing or modifying the STL model, adding the artificial construction, and creating the complex assistant support structure to meet the special technical requests. The topological structure of STL models was built firstly in order to obtain the neighborhood relationship among the triangular facets. The intersection test between every edge of one solid and every facet of another solid was taken to get the intersection points. According to the matching relationship of the triangle index recorded in the data structure of the intersection points, the intersection segments array and the intersection loop were traced out. Each intersected triangle was subdivided by the Constrained Delaunay Triangulations. The intersected surfaces were divided into several surface patches along the intersection loops. The inclusion prediction between the surface patch and the other solid was taken by testing whether the candidate point was inside or outside the solid region of the slice. Detecting the loops for determination of the valid intersection lines greatly increases the efficiency and the reliability of the process. 展开更多
关键词 STL model boolean operations segment-facet intersection loop detection Inclusion test
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A general Boolean semantic modelling approach for complex and intelligent industrial systems in the framework of DES
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作者 XU Changyi WANG Yun +1 位作者 DUAN Yiman ZHANG Chao 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1219-1230,共12页
Discrete event system(DES)models promote system engineering,including system design,verification,and assessment.The advancement in manufacturing technology has endowed us to fabricate complex industrial systems.Conseq... Discrete event system(DES)models promote system engineering,including system design,verification,and assessment.The advancement in manufacturing technology has endowed us to fabricate complex industrial systems.Consequently,the adoption of advanced modeling methodologies adept at handling complexity and scalability is imperative.Moreover,industrial systems are no longer quiescent,thus the intelligent operations of the systems should be dynamically specified in the model.In this paper,the composition of the subsystem behaviors is studied to generate the complexity and scalability of the global system model,and a Boolean semantic specifying algorithm is proposed for generating dynamic intelligent operations in the model.In traditional modeling approaches,the change or addition of specifications always necessitates the complete resubmission of the system model,a resource-consuming and error-prone process.Compared with traditional approaches,our approach has three remarkable advantages:(i)an established Boolean semantic can be fitful for all kinds of systems;(ii)there is no need to resubmit the system model whenever there is a change or addition of the operations;(iii)multiple specifying tasks can be easily achieved by continuously adding a new semantic.Thus,this general modeling approach has wide potential for future complex and intelligent industrial systems. 展开更多
关键词 industrial complex system operation specifying boolean semantic discrete event system(DES)theory intelligent operation
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Robust Boolean Operation for Sculptured Models
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作者 唐敏 《High Technology Letters》 EI CAS 2000年第1期45-51,共7页
To enhance the ability of current modeling system, an uniformed representation is designed to represent wire frame, solid, surface models. We present an algorithm for Boolean operation between the models under this r... To enhance the ability of current modeling system, an uniformed representation is designed to represent wire frame, solid, surface models. We present an algorithm for Boolean operation between the models under this representation. Accuracy, efficiency and robustness are the main consideration. The geometric information is represented with trimmed parametric patches and trimmed parametric splines. The topological information is represented with an extended half edge data structure. In the process of intersection calculation, hierarchy intersection method is applied for unified classification. Tracing the intersection curve to overcome degenerate cases that occur frequently in practice. The algorithm has been implemented as the modeling kernel of a feature based modeling system named GS CAD98, which was developed on Windows/NT platform. 展开更多
关键词 Trimmed PATCH boolean operation Sculptured MODEL ROBUSTNESS
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AN ALGORITHM ACHIEVING VALID BOOLEAN OPERATION RESULTS ON POLYHEDRAL SOLIDS
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作者 YING Daoning GU Zhengchao WANG Erjian HU Zengjia Ronghang Mold High-Tech Institute,Zhejiang University,Hangzhou 310027 P.R.China 《Computer Aided Drafting,Design and Manufacturing》 1992年第1期9-15,共7页
A polyhedral solid modeler that operates on boundary representations (B-reps) of ob- jects must derive topological information from numerical data.Due to finite precision of the com- puter,unavoidable numerical calcul... A polyhedral solid modeler that operates on boundary representations (B-reps) of ob- jects must derive topological information from numerical data.Due to finite precision of the com- puter,unavoidable numerical calculation errors may result in ambiguous or contradictory decision of topology.These effects cause existing polyhedral modelers to fail when confronted with objects that nearly align or barely intersect. Based on analysing the reasons which cause the failure of Boolean operation to fail,this paper describes an algorithm using solid integrity to carefully design each step of Boolean operation,so that valid polyhedral modeling results may be achieved. 展开更多
关键词 boolean operation solid modeling numerical uncertainty
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Pointwise Approximation for the Iterated Boolean Sums of Bernstein Operators
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作者 HUO Xiao-yan LI Cui-xiang YAO Qiu-mei 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第1期129-138,共10页
In this paper, with the help of modulus of smoothness ω2r(f,t), we discuss the pointwise approximation properties for the iterated Boolean sums of Bernstein operator B n and obtain direct and inverse theorems when ... In this paper, with the help of modulus of smoothness ω2r(f,t), we discuss the pointwise approximation properties for the iterated Boolean sums of Bernstein operator B n and obtain direct and inverse theorems when 1-1/r ≤λ≤ 1, r ∈N. 展开更多
关键词 Bernstein operators the iterated boolean sums modulus of smoothness
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Fast,Exact and Robust Set Operations on Polyhedrons Using Localized Constructive Solid Geometry Trees
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作者 Ping Lu Xudong Jiang +2 位作者 Wei Lu Ran Wei Bin Sheng 《ZTE Communications》 2015年第3期57-66,共10页
Regularized Boolean operations have been widely used in 3D modeling systems. However, evaluating Boolean operations may be quite numerically unstable and time consuming, especially for iterated set operations. A novel... Regularized Boolean operations have been widely used in 3D modeling systems. However, evaluating Boolean operations may be quite numerically unstable and time consuming, especially for iterated set operations. A novel and unified technique is proposed in this paper for computing single and iterated set operations efficiently, robustly and exactly. An adaptive octree is combined with a nested constructive solid geometry (CSG) tree by this technique. The intersection handling is restricted to the cells in the octree where intersection actually occurs. Within those cells, a CSG tree template is instanced by the surfaces and the tree is converted to planebased binary space partitioning (BSP) for set evaluation; Moreover, the surface classification is restricted to the ceils in the octree where the surfaces only come from a model and are within the bounding-boxes of other polyhedrons. These two ways bring about the efficiency and scalability of the operations, in terms of runtime and memory. As all surfaces in such a cell have the same classification relation, they are classified as a whole. Robustness and exactness are achieved by integrating plane-based geometry representation with adaptive geometry predicate technique in intersection handling, and by applying divide-and-conquer arithmetic on surface classification. Experimental results demonstrate that the proposed approach can guarantee the robustness of Boolean computations and runs faster than other existing approaches. 展开更多
关键词 boolean operations polyhedrons constructive solid geometry binary space partitioning tree
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A NEW PLANAR BOOLEAN OPERATIO ALGORITHM BASED ON LINE SEGMENT SORTING
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作者 Ruibin Qu 《Computer Aided Drafting,Design and Manufacturing》 1995年第2期37-43,共4页
This paper presents a new method of Boolean operation First, a linesegment-polygonclassification theorem is proposed. Then, according to this theorem and basic idea for Booleanoperation, we give the discussion and app... This paper presents a new method of Boolean operation First, a linesegment-polygonclassification theorem is proposed. Then, according to this theorem and basic idea for Booleanoperation, we give the discussion and apposition of the new method. At last, a typical applicationis given. 展开更多
关键词 boolean operation position value
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面向数控车床的切削加工仿真方法
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作者 张剑飞 李亚南 《齐齐哈尔大学学报(自然科学版)》 2024年第3期28-33,共6页
针对现有数控加工仿真系统中存在的加工过程动态仿真效果差、切削加工仿真类型有限以及系统交互性不足等问题,结合加工工件的几何外形和成形特征,采用基于二维边界表示法(B-rep)模型生成算法,实现回转体工件模型的快速生成和更新。在虚... 针对现有数控加工仿真系统中存在的加工过程动态仿真效果差、切削加工仿真类型有限以及系统交互性不足等问题,结合加工工件的几何外形和成形特征,采用基于二维边界表示法(B-rep)模型生成算法,实现回转体工件模型的快速生成和更新。在虚拟数控车床上的应用实验表明,该方法能够高效地生成和更新工件模型,满足实时监控的要求。基于布尔运算的二维B-rep多边形切削算法实现了内径加工、外径加工和螺纹加工3种切削类型的加工模拟,提升了系统的仿真能力和灵活性。 展开更多
关键词 加工过程仿真 车削加工 布尔运算 工件模型 B-REP
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压气机叶片激光熔化沉积修复的机器人路径自动规划和试验研究
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作者 梁旭峰 蔡振华 +4 位作者 刘琦 牟梓鑫 曾春年 牛少鹏 邓春明 《航空制造技术》 CSCD 北大核心 2024年第13期119-126,共8页
针对航空发动机TC17高压压气机叶片服役损伤后的修复问题,本文基于工业机器人的激光熔化沉积路径生成策略,提出使用模型布尔运算来分析叶片损伤区域,并在RobotStudio离线编程软件中嵌入二次开发插件分别生成Zigzag轴向扫描、中心线偏移... 针对航空发动机TC17高压压气机叶片服役损伤后的修复问题,本文基于工业机器人的激光熔化沉积路径生成策略,提出使用模型布尔运算来分析叶片损伤区域,并在RobotStudio离线编程软件中嵌入二次开发插件分别生成Zigzag轴向扫描、中心线偏移扫描和边缘螺旋扫描路径。路径的仿真和沉积形貌分析表明,在设定扫描速度5 mm/s、沉积层厚度0.3 mm、搭接率50%时,中心线偏移扫描在95.97%时间内保持速度稳定,折返点处的速度下降幅度更小,同时沉积后表面高度接近0.3 mm,高度波动方差更小,保持了较高的平整度。此外,矩形平板区域的沉积模拟和试验表明,类似Zigzag扫描的连续路径可以显著降低成形表面的残余应力。 展开更多
关键词 压气机叶片 激光熔化沉积技术 工业机器人 模型布尔运算 路径规划
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多元Stancu算子的Boolean和迭代 被引量:3
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作者 曹飞龙 王宏勇 《数学进展》 CSCD 北大核心 2005年第5期600-608,共9页
定义单纯形上高维Stancu算子的Boolean和迭代算子并且研究它逼近连续函数的正定理、逆定理与饱和定理,得到了较高的逼近阶.
关键词 STANCU算子 boolean 迭代算子 正定理 逆定理 饱和
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粗糙集的两种新型算子及其Boolean代数性质 被引量:2
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作者 张化光 梁洪力 《应用科学学报》 CAS CSCD 2004年第4期503-508,共6页
主要定义两种新型算子并讨论基于这两种新型算子的粗糙集的代数性质.基于这两种算子建立了粗糙集的并、交、补运算,并证明在此定义下的粗糙集补集为Boolean补.
关键词 代数性质 算子 补集 粗糙集 证明 运算
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犬胃切开手术仿真实训系统关键技术研究
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作者 纪昌宁 冯德万 《计算机仿真》 2024年第5期291-295,共5页
在手术仿真实训系统中,针对无法同时展示仿真模型内外表面,以及无法兼顾切开仿真效果和交互式操作要求的传统算法,提出了一种犬胃切开过程的交互式仿真算法。不需要任何预处理流程,而是根据交互式操作的位置,自动生成对应的动态骨骼和... 在手术仿真实训系统中,针对无法同时展示仿真模型内外表面,以及无法兼顾切开仿真效果和交互式操作要求的传统算法,提出了一种犬胃切开过程的交互式仿真算法。不需要任何预处理流程,而是根据交互式操作的位置,自动生成对应的动态骨骼和蒙皮数据,以及作为内表面渲染的CSG几何体数据,解决了同时展示模型内外表面仿真效果和交互式操作要求的问题,实现了一个实时的犬胃切开手术实训仿真系统,并进行了初步的推广应用。实践表明,上述系统具有操作简单,效率高,渲染效果较好的特点,可以用于相关动物外科手术的仿真训练教学中。 展开更多
关键词 犬胃切开术 虚拟仿真 布尔运算 骨骼动画
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关于用线性正算子与Lagrange插值算子的Boolean和逼近
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作者 罗俊波 《辽宁大学学报(自然科学版)》 CAS 1992年第1期5-8,共4页
本文是对文[1]的一个注记,将该文的结果推广到多个插值结点的情形,从而在插值结点附近逼近度可以得到改善。
关键词 线性正算子 L-插值多项式 布尔和
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原子Boolean格代数的模中有限秩算子的性质
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作者 赵文玲 宋道金 《淄博学院学报(自然科学与工程版)》 2000年第4期11-15,共5页
本文对原子 Boolean格代数模中的有限秩算子进行了讨论,得到了一些结论,这些结论是子空间格代数中相应结论的推广 .
关键词 原子boolean格代数 原子boolean格代数的模 有限秩算子
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Linear Operators That Strongly Preserve Nilpotent Matrices over Antinegative Semirings 被引量:2
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作者 李红海 谭宜家 《Northeastern Mathematical Journal》 CSCD 2007年第1期71-86,共16页
Let S be an antinegative commutative semiring without zero divisors and Mn(S) be the semiring of all n × n matrices over S. For a linear operator L on Mn(S), we say that L strongly preserves nilpotent matrice... Let S be an antinegative commutative semiring without zero divisors and Mn(S) be the semiring of all n × n matrices over S. For a linear operator L on Mn(S), we say that L strongly preserves nilpotent matrices in Mn(S) if for any A ∈ Mn(S), A is nilpotent if and only if L(A) is nilpotent. In this paper, the linear operators that strongly preserve nilpotent matrices over S are characterized. 展开更多
关键词 antinegative commutative semiring boolean algebra nilpotent matrix linear operator
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Computational Resolution of a Boolean Equation of 21 Variables
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作者 Esther Claudine Bitye Mvondo 《American Journal of Operations Research》 2022年第5期157-178,共22页
The Alienor method has been elaborated at the beginning of the 1980s by Yves Cherruault and Arthur Guillez (1983). The following people have also greatly contributed to the improvement of this new optimization method:... The Alienor method has been elaborated at the beginning of the 1980s by Yves Cherruault and Arthur Guillez (1983). The following people have also greatly contributed to the improvement of this new optimization method: Blaise Somé, Gaspar Mora, Balira Konfé, Jean Claude Mazza and Esther Claudine Bityé Mvondo. The basic idea consists in using a reducing transformation allowing us to simplify a multivariable optimization problem to a new optimization problem according to a single variable. The rational gestion of enterprises leads generally to the use of Operational Research, often called management science. The term Operational Research means a scientific approach to decision making, that seeks optimization in a system. Consequently, it is better to take the right decisions. Otherwise, fatal consequences can occur instantaneously [1]. Generally, we have to maximize the global profit margin, taking into account some constraints. For instance, in an integer programming problem, some or all the variables are required to be nonnegative integers. In this paper, we present new reducing transformations for global optimization in integer, binary and mixed variables as well as the applications in Boolean algebra by solving a Boolean Equation of 21 variables. The applications in Operational Research are presented on various examples, resolved by using the tabulator Excel of Microsoft. 展开更多
关键词 Alpha-Dense Curves boolean Equations Diophantine Equations Global Optimization and operational Research
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基于LDP运算路径规划的智能电网储能与分配决策研究 被引量:2
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作者 欧志新 李继侠 邓春兰 《衡阳师范学院学报》 2023年第6期49-56,共8页
本文基于LDP(LogicDynamicProgramming,逻辑动态规划)运算路径为载体的智能电网决策与调度运维系统,从而为有效地决策电网电能总需求供应和分配提供支持。首先,面对电能存储和分布模式的智能化、数字化应用,研究动态电能分流存储和分配... 本文基于LDP(LogicDynamicProgramming,逻辑动态规划)运算路径为载体的智能电网决策与调度运维系统,从而为有效地决策电网电能总需求供应和分配提供支持。首先,面对电能存储和分布模式的智能化、数字化应用,研究动态电能分流存储和分配机制的模型与算法。其次,逻辑控制规则能有效调节误差和波动现象,泛布尔运算原理将误差与误差率扩展至九点分区施加控制力,对智能决策和电能储存在稳定性和鲁棒性平衡方面具有融合效果。最后,通过自适应学习选取和神经网络为对象的路径比较,得出基于LDP运算的逻辑控制在变电站设备正常运维和故障智能诊断、精准分配决策与调控、数据采样分析等方面具有最优动态规划路径解。 展开更多
关键词 智能电网路径决策 电能存储分配 相平面分区 泛布尔运算 逻辑控制规则
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基于自适应轮廓骨架分区的电弧增材制造成形路径优化方法 被引量:1
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作者 赵淘 闫朝阳 +2 位作者 蒋凡 肖珺 陈树君 《焊接学报》 EI CAS CSCD 北大核心 2023年第10期34-40,63,I0004,I0005,共10页
传统轮廓偏置路径规划方法具有较高几何还原度,适合电弧增材制造中等尺寸的复杂零件,但轮廓连续偏置过程中的退化现象易形成欠填充区域,进而导致缺陷,形成待优化区.针对上述问题,提出了基于布尔运算的待优化区域精确识别方法.将原始多... 传统轮廓偏置路径规划方法具有较高几何还原度,适合电弧增材制造中等尺寸的复杂零件,但轮廓连续偏置过程中的退化现象易形成欠填充区域,进而导致缺陷,形成待优化区.针对上述问题,提出了基于布尔运算的待优化区域精确识别方法.将原始多边形与经过正反两次等距偏置的回溯多边形进行布尔差运算,可获得需要优化的缺陷区域,将待优化区域过滤与合并,重新构建为骨架填充区.结合最小矩形框确定每个骨架填充区的最优填充方向并生成往复直线路径,最后将轮廓偏置路径重新分类分区连接为连续成形路径,并按照骨架填充区成形路径优先打印原则输出为机器代码.后续成形试验采用机器人电弧增材制造系统打印了螺旋桨零件,结果表明,零件成形尺寸达到预期,且表面不存在传统轮廓偏置法中的成形缺陷,证明文中方法具有较高的可行性与适用性.创新点:(1)提出了一种骨架填充方法来准确识别和过滤传统轮廓偏置法中的待优化区域.(2)基于布尔运算的待优化区域精确识别方法,既保留了传统方法的优点,又减少了起熄弧次数. 展开更多
关键词 电弧增材制造 轮廓偏置 布尔运算 缺陷识别 混合路径规划
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三元概念的布尔矩阵表示方法 被引量:1
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作者 王霞 李俊余 吴伟志 《计算机科学》 CSCD 北大核心 2023年第6期109-115,共7页
将布尔矩阵引入到三元概念分析,研究三元背景和三元概念的布尔矩阵表示方法。首先,定义三元背景的关系矩阵,将每一个条件下的三元背景看作一个布尔矩阵,那么三元背景是一个布尔分块矩阵,该布尔分块矩阵即为三元背景的关系矩阵。然后,利... 将布尔矩阵引入到三元概念分析,研究三元背景和三元概念的布尔矩阵表示方法。首先,定义三元背景的关系矩阵,将每一个条件下的三元背景看作一个布尔矩阵,那么三元背景是一个布尔分块矩阵,该布尔分块矩阵即为三元背景的关系矩阵。然后,利用关系矩阵给出三元背景上诱导算子的布尔矩阵表示方法,进而得到生成三元概念的外延、内涵和方式的布尔矩阵表示方法,该方法在生成三元概念时只使用一些基本的布尔矩阵运算而不涉及三元背景的诱导算子。最后,给出构造三元概念的枚举法的布尔矩阵表示方法以及基于对象-条件三元概念构造三元概念的布尔矩阵表示方法。三元概念的布尔矩阵表示方法从矩阵的角度理解三元背景和三元概念,为研究三元概念分析提供了新的视角。 展开更多
关键词 三元概念分析 三元背景 三元概念 诱导算子 布尔矩阵
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