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Buckling Optimization of Curved Grid Stiffeners through the Level Set Based Density Method
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作者 Zhuo Huang Ye Tian +2 位作者 Yifan Zhang Tielin Shi Qi Xia 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期711-733,共23页
Stiffened structures have great potential for improvingmechanical performance,and the study of their stability is of great interest.In this paper,the optimization of the critical buckling load factor for curved grid s... Stiffened structures have great potential for improvingmechanical performance,and the study of their stability is of great interest.In this paper,the optimization of the critical buckling load factor for curved grid stiffeners is solved by using the level set based density method,where the shape and cross section(including thickness and width)of the stiffeners can be optimized simultaneously.The grid stiffeners are a combination ofmany single stiffenerswhich are projected by the corresponding level set functions.The thickness and width of each stiffener are designed to be independent variables in the projection applied to each level set function.Besides,the path of each single stiffener is described by the zero iso-contour of the level set function.All the single stiffeners are combined together by using the p-norm method to obtain the stiffener grid.The proposed method is validated by several numerical examples to optimize the critical buckling load factor. 展开更多
关键词 STIFFENER buckling optimization shape and cross section level set based density
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Solving the k-Independent Sets Problem of Graphs by Gröbner Bases
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作者 Junyu Luo Shengzhen Ding 《Open Journal of Discrete Mathematics》 2023年第3期86-94,共9页
The aim of this paper is to given an algebraic computational method for finding maximal independent sets as well as the independent number of an arbitrary finite graph of n vertices G by strengthening the problem of f... The aim of this paper is to given an algebraic computational method for finding maximal independent sets as well as the independent number of an arbitrary finite graph of n vertices G by strengthening the problem of finding maximal independent sets of G to the problem of finding k-independent sets in G for. It is shown that the existence of k-independent sets in G is equivalent to the existence of solutions of a system of multivariate polynomial equations. It follows that the problem of finding k-independent sets can be realized by using Gröbner bases of polynomial ideals. Since the number of k-independent sets is finite, the triangular equations composed by Gröbner bases are easier to be solved. Consequently, the maximal independent sets and the independent number of G are obtained after solving at most n such equations. Finally, the numerical example is presented to illustrate the effectiveness of this algebraic computational method. 展开更多
关键词 k-Independent set Maximal Independent set Gröbner bases
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Phase-Based Optical Flow Method with Optimized Parameter Settings for Enhancing Displacement Measurement Adaptability
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作者 Zhaoxin Peng Menglian Liu +2 位作者 Zhiliang Wang Wei Liu Xian Wang 《Open Journal of Applied Sciences》 2024年第5期1165-1184,共20页
To enhance the applicability and measurement accuracy of phase-based optical flow method using complex steerable pyramids in structural displacement measurement engineering applications, an improved method of optimizi... To enhance the applicability and measurement accuracy of phase-based optical flow method using complex steerable pyramids in structural displacement measurement engineering applications, an improved method of optimizing parameter settings is proposed. The optimized parameters include the best measurement points of the Region of Interest (ROI) and the levels of pyramid filters. Additionally, to address the issue of updating reference frames in practical applications due to the difficulty in estimating the maximum effective measurement value, a mechanism for dynamically updating reference frames is introduced. Experimental results demonstrate that compared to representative image gradient-based displacement measurement methods, the proposed method exhibits higher measurement accuracy in engineering applications. This provides reliable data support for structural damage identification research based on vibration signals and is expected to broaden the engineering application prospects for structural health monitoring. 展开更多
关键词 Displacement Measurement Phase-based Optical Flow Optimized Parameter setting
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Covering-Based Soft Rough Sets 被引量:1
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作者 Jian-Guo Tang Kun She Yu-Qi Wang 《Journal of Electronic Science and Technology》 CAS 2011年第2期118-123,共6页
Covering-based rough sets process data organized by a covering of the universe. A soft set is a parameterized family of subsets of the universe. Both theories can deal with the uncertainties of data. Soft sets have no... Covering-based rough sets process data organized by a covering of the universe. A soft set is a parameterized family of subsets of the universe. Both theories can deal with the uncertainties of data. Soft sets have not any restrictions on the approximate description of the object,and they might form a covering of the universe. From this viewpoint,we establish a connection between these two theories. Specifically,we propose a complementary parameter for this purpose. With this parameter,the soft covering approximation space is established and the two theories are bridged. Furthermore,we study some relations between the covering and the soft covering approximation space and obtain some significant results. Finally,we define a notion of combine parameter which can help us to simplify the set of parameters and reduce the storage requirement of a soft covering approximation space. 展开更多
关键词 Complementary parameter covering-based rough sets covering-element soft set
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Stable Border Bases for Ideals of Numerical Cartesian Sets
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作者 LIU LI-LI LI ZHE ZHANG SHU-GONG 《Communications in Mathematical Research》 CSCD 2011年第3期243-252,共10页
In this paper, we discuss a special class of sets of bivariate empirical points, namely, numerical cartesian sets. We find that the stable quotient bases for numerical cartesian sets are unique if they exist. Furtherm... In this paper, we discuss a special class of sets of bivariate empirical points, namely, numerical cartesian sets. We find that the stable quotient bases for numerical cartesian sets are unique if they exist. Furthermore, the corresponding border bases are the unique stable border bases for the vanishing ideals of numerical cartesian sets. 展开更多
关键词 empirical point numerical cartesian set vanishing ideal border base
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Keystroke Dynamics Based Authentication Using Information Sets
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作者 Aparna Bhatia Madasu Hanmandlu 《Journal of Modern Physics》 2017年第9期1557-1583,共27页
This paper presents keystroke dynamics based authentication system using the information set concept. Two types of membership functions (MFs) are computed: one based on the timing features of all the samples and anoth... This paper presents keystroke dynamics based authentication system using the information set concept. Two types of membership functions (MFs) are computed: one based on the timing features of all the samples and another based on the timing features of a single sample. These MFs lead to two types of information components (spatial and temporal) which are concatenated and modified to produce different feature types. Two Component Information Set (TCIS) is proposed for keystroke dynamics based user authentication. The keystroke features are converted into TCIS features which are then classified by SVM, Random Forest and proposed Convex Entropy Based Hanman Classifier. The TCIS features are capable of representing the spatial and temporal uncertainties. The performance of the proposed features is tested on CMU benchmark dataset in terms of error rates (FAR, FRR, EER) and accuracy of the features. In addition, the proposed features are also tested on Android Touch screen based Mobile Keystroke Dataset. The TCIS features improve the performance and give lower error rates and better accuracy than that of the existing features in literature. 展开更多
关键词 INFORMATION set Theory Two Component INFORMATION set Features Support Vector Machines (SVM) Random Forest CONVEX Hanman-Anirban ENTROPY Function Hanman CLASSIFIER CONVEX ENTROPY baseD CLASSIFIER
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3D Surface Editing Based on Level-Sets
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作者 林茂松 张典华 《Journal of Southwest Jiaotong University(English Edition)》 2005年第2期139-146,共8页
A novel method which integrates the topological flexibility of the level-set approach and the simplicity of point-sampled surfaces is proposed. The grid structure resulted from the level-set approach not only offers a... A novel method which integrates the topological flexibility of the level-set approach and the simplicity of point-sampled surfaces is proposed. The grid structure resulted from the level-set approach not only offers a wide range of powerful surface editing techniques for the point set surface editing, but also facilitates the topological change with ease. With the aid of point-based resampling, the method updates the surface shape of the point-based geometry quickly without worrying about point connectivity at all. The point set surface can also change its topology properly whenever a collision with other parts of itself is detected. The experiment demonstrates their effectiveness on several scanned objects and scan-converted models. Four examples of surface editing operations: smoothing, tapering, deforming, and Boolean operations, are presented. 展开更多
关键词 Computational geometry Level-set methods Point-based geometry DEFORMATION
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Capacity Set Optimization of Knowledge-Based Enterprise and Its Organizational IQ 被引量:1
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作者 王文平 《Journal of Southeast University(English Edition)》 EI CAS 2002年第3期259-264,共6页
In this paper, the knowledge based enterprise is considered as an organism, which possesses a set of capabilities. The organizational structure model of knowledge based enterprise organism is described in order to pos... In this paper, the knowledge based enterprise is considered as an organism, which possesses a set of capabilities. The organizational structure model of knowledge based enterprise organism is described in order to possess the essential capacity set. A dynamic capacity set is defined and analyzed based on the definition of the growth and development for knowledge based enterprise organism. The structure of the capacity base, a subset of the capacity set, is optimized for different periods of the organism ... 展开更多
关键词 knowledge based enterprise capacity set organizational IQ
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基于RoughSets的图像分割法
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作者 余英泽 胡振鹏 《南昌大学学报(工科版)》 CAS 2000年第1期33-37,共5页
介绍了粗集 (RoughSets)的一般概念和理论 ,并提出了一种基于粗集理论中不可分辨关系的图像分割方法 。
关键词 粗集 知识库 不可分辨关系 图像分割
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Anomaly Detection of Complex Networks Based on Intuitionistic Fuzzy Set Ensemble 被引量:1
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作者 Jin-Fa Wang Xiao Liu +1 位作者 Hai Zhao Xing-Chi Chen 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第5期156-160,共5页
Ensemble learning for anomaly detection of data structured into a complex network has been barely studied due to the inconsistent performance of complex network characteristics and the lack of inherent objective funct... Ensemble learning for anomaly detection of data structured into a complex network has been barely studied due to the inconsistent performance of complex network characteristics and the lack of inherent objective function. We propose the intuitionistic fuzzy set(IFS)-based anomaly detection, a new two-phase ensemble method for anomaly detection based on IFS, and apply it to the abnormal behavior detection problem in temporal complex networks.Firstly, it constructs the IFS of a single network characteristic, which quantifies the degree of membership,non-membership and hesitation of each network characteristic to the defined linguistic variables so that makes the unuseful or noise characteristics become part of the detection. To build an objective intuitionistic fuzzy relationship, we propose a Gaussian distribution-based membership function which gives a variable hesitation degree. Then, for the fuzzification of multiple network characteristics, the intuitionistic fuzzy weighted geometric operator is adopted to fuse multiple IFSs and to avoid the inconsistence of multiple characteristics. Finally, the score function and precision function are used to sort the fused IFS. Finally, we carry out extensive experiments on several complex network datasets for anomaly detection, and the results demonstrate the superiority of our method to state-of-the-art approaches, validating the effectiveness of our method. 展开更多
关键词 NET IFS Anomaly Detection of Complex Networks based on Intuitionistic Fuzzy set Ensemble
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A Correntropy-based Affine Iterative Closest Point Algorithm for Robust Point Set Registration 被引量:7
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作者 Hongchen Chen Xie Zhang +2 位作者 Shaoyi Du Zongze Wu Nanning Zheng 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第4期981-991,共11页
The iterative closest point(ICP)algorithm has the advantages of high accuracy and fast speed for point set registration,but it performs poorly when the point set has a large number of noisy outliers.To solve this prob... The iterative closest point(ICP)algorithm has the advantages of high accuracy and fast speed for point set registration,but it performs poorly when the point set has a large number of noisy outliers.To solve this problem,we propose a new affine registration algorithm based on correntropy which works well in the affine registration of point sets with outliers.Firstly,we substitute the traditional measure of least squares with a maximum correntropy criterion to build a new registration model,which can avoid the influence of outliers.To maximize the objective function,we then propose a robust affine ICP algorithm.At each iteration of this new algorithm,we set up the index mapping of two point sets according to the known transformation,and then compute the closed-form solution of the new transformation according to the known index mapping.Similar to the traditional ICP algorithm,our algorithm converges to a local maximum monotonously for any given initial value.Finally,the robustness and high efficiency of affine ICP algorithm based on correntropy are demonstrated by 2D and 3D point set registration experiments. 展开更多
关键词 AFFINE ITERATIVE closest point(ICP)algorithm correntropy-based ROBUST POINT set REGISTRATION
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Structural Topology Design of Container Ship Based on Knowledge-Based Engineering and Level Set Method 被引量:5
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作者 崔进举 王德禹 史琪琪 《China Ocean Engineering》 SCIE EI CSCD 2015年第4期551-564,共14页
Knowledge-Based Engineering (KBE) is introduced into the ship structural design in this paper. From the implementation of KBE, the design solutions for both Rules Design Method (RDM) and Interpolation Design Meth... Knowledge-Based Engineering (KBE) is introduced into the ship structural design in this paper. From the implementation of KBE, the design solutions for both Rules Design Method (RDM) and Interpolation Design Method (IDM) are generated. The corresponding Finite Element (FE) models are generated. Topological design of the longitudinal structures is studied where the Gaussian Process (GP) is employed to build the surrogate model for FE analysis. Multi-objective optimization methods inspired by Pareto Front are used to reduce the design tank weight and outer surface area simultaneously. Additionally, an enhanced Level Set Method (LSM) which employs implicit algorithm is applied to the topological design of typical bracket plate which is used extensively in ship structures. Two different sets of boundary conditions are considered. The proposed methods show satisfactory efficiency and accuracy. 展开更多
关键词 Knowledge-based Engineering (KBE) Level set Method (LSM) Gaussian Process GP)
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Density-based rough set model for hesitant node clustering in overlapping community detection 被引量:2
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作者 Jun Wang Jiaxu Peng Ou Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第6期1089-1097,共9页
Overlapping community detection in a network is a challenging issue which attracts lots of attention in recent years.A notion of hesitant node(HN) is proposed. An HN contacts with multiple communities while the comm... Overlapping community detection in a network is a challenging issue which attracts lots of attention in recent years.A notion of hesitant node(HN) is proposed. An HN contacts with multiple communities while the communications are not strong or even accidental, thus the HN holds an implicit community structure.However, HNs are not rare in the real world network. It is important to identify them because they can be efficient hubs which form the overlapping portions of communities or simple attached nodes to some communities. Current approaches have difficulties in identifying and clustering HNs. A density-based rough set model(DBRSM) is proposed by combining the virtue of densitybased algorithms and rough set models. It incorporates the macro perspective of the community structure of the whole network and the micro perspective of the local information held by HNs, which would facilitate the further "growth" of HNs in community. We offer a theoretical support for this model from the point of strength of the trust path. The experiments on the real-world and synthetic datasets show the practical significance of analyzing and clustering the HNs based on DBRSM. Besides, the clustering based on DBRSM promotes the modularity optimization. 展开更多
关键词 density-based rough set model(DBRSM) overlapping community detection rough set hesitant node(HN) trust path
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Solving the independent set problem by sticker based DNA computers
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作者 Hassan Taghipour Ahad Taghipour +1 位作者 Mahdi Rezaei Heydar Ali Esmaili 《American Journal of Molecular Biology》 2012年第2期153-158,共6页
In this paper, the sticker based DNA computing was used for solving the independent set problem. At first, solution space was constructed by using appropriate DNA memory complexes. We defined a new operation called “... In this paper, the sticker based DNA computing was used for solving the independent set problem. At first, solution space was constructed by using appropriate DNA memory complexes. We defined a new operation called “divide” and applied it in construction of solution space. Then, by application of a sticker based parallel algorithm using biological operations, independent set problem was resolved in polynomial time. 展开更多
关键词 Parallel Computing Sticker baseD DNA COMPUTERS INDEPENDENT set PROBLEM NP-COMPLETE PROBLEM
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Multi-objective optimization based optimal setting control for industrial double-stream alumina digestion process
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作者 WANG Xiao-li LU Mei-yu +1 位作者 WEI Si-mi XIE Yong-fang 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第1期173-185,共13页
The operation variables,including feed rate of ore slurry,caustic solution and live steams in the double-stream alumina digestion process,determine the product quality,process costs and the environment pollution.Previ... The operation variables,including feed rate of ore slurry,caustic solution and live steams in the double-stream alumina digestion process,determine the product quality,process costs and the environment pollution.Previously,they were set by the technical workers according to the offline analysis results and an empirical formula,which leads to unstable process indices and high consumption frequently.So,a multi-objective optimization model is built to maintain the balance between resource consumptions and process indices by taking technical indices and energy efficiency as objectives,where the key technical indices are predicted based on the digestion kinetics of diaspore.A multi-objective state transition algorithm(MOSTA)is improved to solve the problem,in which a self-adaptive strategy is applied to dynamically adjust the operator factors of the MOSTA and dynamic infeasible threshold is used to handle constraints to enhance searching efficiency and ability of the algorithm.Then a rule based strategy is designed to make the final decision from the Pareto frontiers.The method is integrated into an optimal control system for the industrial digestion process and tested in the actual production.Results show that the proposed method can achieve the technical target while reducing the energy consumption. 展开更多
关键词 double-stream digestion process optimal setting control multi-objective optimization state transition algorithm rule based decision making
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Yarn Quality Prediction and Diagnosis Based on Rough Set and Knowledge-Based Artificial Neural Network 被引量:1
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作者 杨建国 徐兰 +1 位作者 项前 刘彬 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期817-823,共7页
In the spinning process, some key process parameters( i. e.,raw material index inputs) have very strong relationship with the quality of finished products. The abnormal changes of these process parameters could result... In the spinning process, some key process parameters( i. e.,raw material index inputs) have very strong relationship with the quality of finished products. The abnormal changes of these process parameters could result in various categories of faulty products. In this paper, a hybrid learning-based model was developed for on-line intelligent monitoring and diagnosis of the spinning process. In the proposed model, a knowledge-based artificial neural network( KBANN) was developed for monitoring the spinning process and recognizing faulty quality categories of yarn. In addition,a rough set( RS)-based rule extraction approach named RSRule was developed to discover the causal relationship between textile parameters and yarn quality. These extracted rules were applied in diagnosis of the spinning process, provided guidelines on improving yarn quality,and were used to construct KBANN. Experiments show that the proposed model significantly improve the learning efficiency, and its prediction precision is improved by about 5. 4% compared with the BP neural network model. 展开更多
关键词 yarn quality prediction rough set(RS) knowledge discovery knowledge-based artificial neural network(KBANN)
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Obstacles in employing evidence-based practice by nurses in their clinical settings: a descriptive study
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作者 Manal Hamed Mahmoud Zizi Fikry Mohamed Abdelrasol 《Frontiers of Nursing》 CAS 2019年第2期123-133,共11页
Objective: The challenge of employing evidence-based practice (EBP) is multifarious and varied. Nursing interventions supported by research evidence have been exposed to progress positive patient outcomes, while its i... Objective: The challenge of employing evidence-based practice (EBP) is multifarious and varied. Nursing interventions supported by research evidence have been exposed to progress positive patient outcomes, while its implementation is faced with various obstacles. This study aimed to identify obstacles in employing EBP by nurses in their clinical settings. Methods: This descriptive design study was conducted at Benha University Hospital with a convenient sample of 154 nurses. Two tools were utilized: (Ⅰ) sociodemographic data sheet, which included sociodemographic characteristics of the participants, and (Ⅱ) interview scale, which contained two parts: (1) obstacles scale, which contained obstacles that impede nurses from the utilization of EBP, and (2) questions to rank the three greatest obstacles in employing EBP by nurses. Results: The greatest EBP obstacle ranked by nurses was the organizational limitations (90.9%), followed by research quality (86.9%) and research accessibility (51.0%), while individual characteristics (35.9%) were ranked as the least obstacle. There was a significant statistical correlation between organizational limitations, research quality as well accessibility-related obstacles and nurses' age, level of education, as well their years of work experience (P<0.05). Conclusions: Findings of this study showed series of obstacles in employing EBP by nurses in their clinical settings, stressing the call for expansion of nurses' capabilities related to EBP utilization in patients' care. 展开更多
关键词 EVIDENCE-baseD PRACTICE CLINICAL setTINGS obstacles
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Content-Based Image Retrieval:Near Tolerance Rough Set Approach
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作者 RAMANNA Sheela PETERS James F WU Wei-zhi 《浙江海洋学院学报(自然科学版)》 CAS 2010年第5期462-471,共10页
The problem considered in this paper is how to detect the degree of similarity in the content of digital images useful in image retrieval,i.e.,to what extent is the content of a query image similar to content of other... The problem considered in this paper is how to detect the degree of similarity in the content of digital images useful in image retrieval,i.e.,to what extent is the content of a query image similar to content of other images.The solution to this problem results from the detection of subsets that are rough sets contained in covers of digital images determined by perceptual tolerance relations(PTRs).Such relations are defined within the context of perceptual representative spaces that hearken back to work by J.H.Poincare on representative spaces as models of physical continua.Classes determined by a PTR provide content useful in content-based image retrieval(CBIR).In addition,tolerance classes provide a means of determining when subsets of image covers are tolerance rough sets(TRSs).It is the nearness of TRSs present in image tolerance spaces that provide a promising approach to CBIR,especially in cases such as satellite images or aircraft identification where there are subtle differences between pairs of digital images,making it difficult to quantify the similarities between such images.The contribution of this article is the introduction of the nearness of tolerance rough sets as an effective means of measuring digital image similarities and,as a significant consequence,successfully carrying out CBIR. 展开更多
关键词 Content-based Image retrieval Near sets PERCEPTION Rough sets Tolerance space
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Interactive multiobjective optimization using dominance-based rough set approach
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作者 GRECO Salvatore MATARAZZO Benedetto SLOWINSKI Roman 《重庆邮电大学学报(自然科学版)》 2008年第3期272-281,共10页
We present main ideas of a recently proposed method for interactive multiobjective optimization,which is based on application of a logical preference model built using the Dominance-based Rough Set Approach(DRSA).
关键词 粗糙集 计算方法 最优化设计 数学理论
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Commonsense Reasoning and Nonmonotonic Aggregation Connectives on Fuzzy Sets
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作者 刘东波 《High Technology Letters》 EI CAS 1995年第2期43-47,共5页
Commonsense representation and manipulation based on fuzzy logic is a new research field which handles the incompleteness, error-tolerability (allow exceptions) and uncertainty associated with commonsense knowledge. I... Commonsense representation and manipulation based on fuzzy logic is a new research field which handles the incompleteness, error-tolerability (allow exceptions) and uncertainty associated with commonsense knowledge. In this paper, we introduce a pair of nonmonotonic aggregation connectives on fuzzy sets-soft intersection and soft union, in the light of Zadeh’s fuzzy set theory. Some important features of the nonmonotonic connectives are also discussed. 展开更多
关键词 cussed. Commonsense knowledge Nonmonotonic REASONING Fuzzy sets SOFT INTERSECTION SOFT UNION
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