نتایج جستجو برای: t rough set

تعداد نتایج: 1335005  

In this paper, we take a GL-quantale as the truth value table to study a new rough set model—L-valued fuzzy rough sets. The three key components of this model are: an L-fuzzy set A as the universal set, an L-valued relation of A and an L-fuzzy set of A (a fuzzy subset of fuzzy sets). Then L-valued fuzzy rough sets are completely characterized via both constructive and axiomatic approaches. 

Classical structure of rough set theory was first formulated by Z. Pawlak in [6]. The foundation of its object classification is an equivalence binary relation and equivalence classes. The upper and lower approximation operations are two core notions in rough set theory. They can also be seenas a closure operator and an interior operator of the topology induced by an equivalence relation on a u...

2014
Wentao Li Xiaoyan Zhang Wenxin Sun

The optimistic multigranulation T-fuzzy rough set model was established based on multiple granulations under T-fuzzy approximation space by Xu et al., 2012. From the reference, a natural idea is to consider pessimistic multigranulation model in T-fuzzy approximation space. So, in this paper, the main objective is to make further studies according to Xu et al., 2012. The optimistic multigranulat...

2015
Xibei Yang Weihua Xu Yanhong She

Recently, the rough set and fuzzy set theory have generated a great deal of interest among more and more researchers. Granular computing (GrC) is an emerging computing paradigm of information processing and an approach for knowledge representation and data mining. The purpose of granular computing is to seek for an approximation scheme which can effectively solve a complex problem at a certain ...

پایان نامه :دانشگاه تربیت معلم - سبزوار - پژوهشکده ریاضیات 1389

اساس نظریه مجموعه های ناهموار، بدین صورت است که برای هر زیرمجموعه از یک مجموعه کلی، با استفاده از یک رابه هم ارزی، یک زوج مرتب از مجموعه ها را معرفی می کند. هر موفه را به ترتیب، تقریب پایینی و بالایی می نامند. تقریب پایین از یک زیرمجموعه،اجتماع تمام عناصری از مجموعه ی کلی است که کلاس هم ارزی مربوط به آن عنصر، در زیرمجموعه ی مورد نظر قرار گیرد و همچنین، تقریب بالا از آن زیرمجموعه، اجتماع تمام عن...

Journal: :Knowl.-Based Syst. 2016
Yanli Sang Jiye Liang Yuhua Qian

Decision-theoretic rough set theory is quickly becoming a research direction in rough set theory, which is a general and typical probabilistic rough set model with respect to its threshold semantics and decision features. However, unlike the Pawlak rough set, the positive region, the boundary region and the negative region of a decision-theoretic rough set are not monotonic as the number of att...

Journal: :Inf. Sci. 2012
Xiaohong Zhang Bing Zhou Peng Li

Intuitionistic fuzzy rough sets are investigated in a general framework which includes generalizations of many related results in early literatures. A new definition of intuitionistic fuzzy rough sets is given with the analysis of its basic properties based on the notion of two universes, general binary relations, and a pair ðT , IÞ of intuitionistic fuzzy t-norm T and intuitionistic fuzzy impl...

2008
Richard Jensen Chris Cornelis

In this paper, we present a new fuzzy-rough nearest neighbour (FRNN) classification algorithm, as an alternative to Sarkar’s fuzzyrough ownership function (FRNN-O) approach. By contrast to the latter, our method uses the nearest neighbours to construct lower and upper approximations of decision classes, and classifies test instances based on their membership to these approximations. In the expe...

Journal: :Trans. Rough Sets 2011
Richard Jensen Chris Cornelis

A new fuzzy-rough nearest neighbour (FRNN) classification algorithm is presented in this paper, as an alternative to Sarkar’s fuzzyrough ownership function (FRNN-O) approach. By contrast to the latter, our method uses the nearest neighbours to construct lower and upper approximations of decision classes, and classifies test instances based on their membership to these approximations. In the exp...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید