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991.
In this paper, we provide a complete framework for the design of genetically evolved cognitive tracking controller based on interval type-2 (IT2) fuzzy cognitive map (FCM). We construct the cognitive controller based on a nonlinear controller by transforming its representation into a FCM. This representation gives the opportunity to prove the stability of the cognitive controller in the framework of nonlinear control theory. Moreover, with the deployment of IT2-fuzzy sets which are known to be capable to handle high level of uncertainty, the proposed cognitive controller has the ability to deal with uncertainty that are encountered in real-time world applications. To accomplish the design of the cognitive controller, we present a systematic approach based on genetic algorithm to optimize its parameters and learn fuzzy rules by extracting them from model space (e.g., a set of rules). Within the paper, all steps in constructing and designing the IT2-FCM-based cognitive controller are presented. We first show the performance improvements of the proposed IT2-FCM-based tracking controller with extensive and comparative simulation results and then with experimental results that were collected on real-world mobile robot. The results clearly show the superiority of proposed cognitive control systems when compared to its conventional and fuzzy controller counterparts. We believe that the proposed genetically evolved design approach of the IT2-FCM-based cognitive controller will provide a bridge between the well-developed cognitive sciences and control theory. 相似文献
992.
Monica Matzenauer Hlida Santos Benjamín Bedregal Humberto Bustince Renata Reiser 《国际智能系统杂志》2022,37(1):264-286
In this paper, we discussconsensus measures for typical hesitant fuzzy elements (THFE), which are the finite and nonempty fuzzy membership degrees under the scope of typical hesitant fuzzy sets (THFS). In our approach, we present a model that formally constructs consensus measures by means of aggregations functions, fuzzy implication-like functions and fuzzy negations, using admissible orders to compare the THFE, and also providing an analysis of consistency on them. Our theoretical results are applied into a problem of decision making with multicriteria illustrating our methodology to achieve consensus in a group of experts working with THFS. 相似文献
993.
Linguistic hesitant fuzzy sets (LHFSs), which can be used to represent decision-makers’ qualitative preferences as well as reflect their hesitancy and inconsistency, have attracted a great deal of attention due to their flexibility and efficiency. This paper focuses on a multi-criteria decision-making approach that combines LHFSs with the evidential reasoning (ER) method. After reviewing existing studies of LHFSs, a new order relationship and Hamming distance between LHFSs are introduced and some linguistic scale functions are applied. Then, the ER algorithm is used to aggregate the distributed assessment of each alternative. Subsequently, the set of aggregated alternatives on criteria are further aggregated to get the overall value of each alternative. Furthermore, a nonlinear programming model is developed and genetic algorithms are used to obtain the optimal weights of the criteria. Finally, two illustrative examples are provided to show the feasibility and usability of the method, and comparison analysis with the existing method is made. 相似文献
994.
Simplified neutrosophic sets and their applications in multi-criteria group decision-making problems
Juan-juan Peng Jing Wang Hong-yu Zhang Xiao-hong Chen 《International journal of systems science》2016,47(10):2342-2358
As a variation of fuzzy sets and intuitionistic fuzzy sets, neutrosophic sets have been developed to represent uncertain, imprecise, incomplete and inconsistent information that exists in the real world. Simplified neutrosophic sets (SNSs) have been proposed for the main purpose of addressing issues with a set of specific numbers. However, there are certain problems regarding the existing operations of SNSs, as well as their aggregation operators and the comparison methods. Therefore, this paper defines the novel operations of simplified neutrosophic numbers (SNNs) and develops a comparison method based on the related research of intuitionistic fuzzy numbers. On the basis of these operations and the comparison method, some SNN aggregation operators are proposed. Additionally, an approach for multi-criteria group decision-making (MCGDM) problems is explored by applying these aggregation operators. Finally, an example to illustrate the applicability of the proposed method is provided and a comparison with some other methods is made. 相似文献
995.
996.
Paw lak粗糙集模型没有对正域、边界域和负域赋予语义,不能进行再决策,而三支决策对边界域赋予了新的语义,可以对边界域做出进一步刻画,对于边界域的进一步划分,依据属性的重要性,使满足条件的样本划入再决策域,不满足条件的样本继续保留在边界域中,降低了边界域样本处理的失误率.本文在对概率粗糙集模型、三支决策粗糙集的理论、贝叶斯理论的决策过程和决策粗糙集模型进行研究的基础上,提出了一种三支决策与决策粗糙集融合模型,与Paw lak-三支决策模型相比,其划分损失更小,处理结果更优.该模型运用三支决策理论对决策粗糙集的边界域赋予延迟决策的语义,对于延迟决策再运用三支决策理论进行迭代操作,对边界域样本进一步处理.在迭代的过程中,依据属性的重要程度将属性排序,从而客观的得到迭代过程中每次优先依据哪个属性进行划分.实验结果表明,该模型比单一运用决策粗糙集模型进行决策代价小,三支决策通过迭代对边界域处理的正确率有所提高,这为准确决策提供了一种新的方法. 相似文献
997.
针对群推荐中存在的多粒度、犹豫性、模糊性语言信息问题, 提出多粒度犹豫模糊语言环境下未知权重的多属性群推荐方法. 首先, 提出多粒度犹豫模糊语言术语集的概念, 定义其距离公式; 然后, 在多粒度犹豫模糊语言环境下, 针对属性权重完全未知的情况, 建立目标规划模型, 利用拉格朗日方程求解, 针对属性权重不完全未知的情况, 建立线性规划模型求解; 最后, 通过算例计算和分析表明了上述模型求解权重问题是有效的.
相似文献998.
999.
单向S-粗集(one direction singular rough sets)与单向S-粗集对偶(dual of one direction singular rough sets)是S-粗集(singular rough sets)的两种动态结构;在一定条件下,单向S-粗集与单向S-粗集对偶被还原成Z.Pawlak粗集.单向S-粗集与单向粗集对偶分别是S-粗集的基本形式之一.利用单向S-粗集与单向S-粗集对偶,给出动态知识的属性合取范式与属性合取范式萎缩-扩张特征,给出知识推理结构与推理模型.利用单向S-粗集,单向S-粗集对偶,属性合取范式与知识推理交叉、融合、渗透,给出具有属性合取范式萎缩-扩张特征的动态知识生成与生成定理;给出在知识推理条件下的动态知识智能发现与它的属性逻辑关系;给出动态知识的智能筛选、筛选准则、筛选定理与应用. 相似文献
1000.
S-粗集(singular rough sets)是把动态特征引入到Z.Pawlak粗集中对其加以改进而提出的,S-粗集具有动态特征.S-粗集具有3种形式:单向S-粗集(one direction singular rough sets)、单向S-粗集对偶(dual of one direction singular rough sets)与双向S-粗集(two direction singular rough sets);在一定条件下,单向S-粗集、单向S-粗集对偶与双向S-粗集被还原成Z.Pawlak粗集.利用单向S-粗集和单向S-粗集对偶给出具有属性析取特征的动态数据智能挖掘与应用;属性析取是数据具有的逻辑特征之一.主要结果是:利用单向S-粗集、单向S-粗集对偶结构,给出属性析取萎缩-扩张特征的动态数据生成与它的属性析取萎缩-扩张关系;给出数据推理与推理模型;利用数据推理给出动态数据智能挖掘定理;利用这些理论结果,给出动态数据智能挖掘-智能认知的应用. 相似文献