Topological Approaches to the Second Type of Covering-Based Rough Sets

2011 ◽  
Vol 204-210 ◽  
pp. 1781-1784
Author(s):  
Bin Chen
Keyword(s):  
Data Mining ◽  
Information Systems ◽  
Rough Sets ◽  
Relative Interior ◽  
Upper Approximation ◽  
Definition Of ◽  
The Relationship

Rough sets, a tool for data mining, deal with the vagueness and granularity in information systems. This paper studies covering-based rough sets from the topological view. We explore the relationship between the relative closure and the second type of covering upper approximation. The major contributions of this paper are that we use the definition of the relative closure and the relative interior to discuss the conditions under which the relative operators satisfy certain classical properties. The theorems we get generalize some of the results in Zhu’s paper.

scholarly journals Four Operators of Rough Sets Generalized to Matroids and a Matroidal Method for Attribute Reduction

Symmetry ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 418 ◽  
Author(s):  
Jingqian Wang ◽  
Xiaohong Zhang
Keyword(s):  
Data Mining ◽  
Information Systems ◽  
Rough Sets ◽  
Greedy Algorithms ◽  
Attribute Reduction ◽  
Data Preprocessing ◽  
The Relationship

Rough sets provide a useful tool for data preprocessing during data mining. However, many algorithms related to some problems in rough sets, such as attribute reduction, are greedy ones. Matroids propose a good platform for greedy algorithms. Therefore, it is important to study the combination between rough sets and matroids. In this paper, we investigate rough sets and matroids through their operators, and provide a matroidal method for attribute reduction in information systems. Firstly, we generalize four operators of rough sets to four operators of matroids through the interior, closure, exterior and boundary axioms, respectively. Thus, there are four matroids induced by these four operators of rough sets. Then, we find that these four matroids are the same one, which implies the relationship about operators between rough sets and matroids. Secondly, a relationship about operations between matroids and rough sets is presented according to the induced matroid. Finally, the girth function of matroids is used to compute attribute reduction in information systems.

Model of Covering Rough Sets in the Machine Intelligence

2012 ◽  
Vol 548 ◽  
pp. 735-739
Author(s):  
Hong Mei Nie ◽  
Jia Qing Zhou
Keyword(s):  
Information Systems ◽  
Set Theory ◽  
Rough Set ◽  
Equivalence Relation ◽  
Rough Sets ◽  
Rough Set Theory ◽  
Machine Intelligence ◽  
Upper Approximation ◽  
Generalized Rough Sets

Rough set theory has been proposed by Pawlak as a useful tool for dealing with the vagueness and granularity in information systems. Classical rough set theory is based on equivalence relation. The covering rough sets are an improvement of Pawlak rough set to deal with complex practical problems which the latter one can not handle. This paper studies covering-based generalized rough sets. In this setting, we investigate common properties of classical lower and upper approximation operations hold for the covering-based lower and upper approximation operations and relationships among some type of covering rough sets.

scholarly journals O papel das bibliotecas no desenvolvimento de sistemas CRIS: Dois estudos de caso em Portugal / The role of libraries in CRIS development: two case studies from Portugal

2019 ◽  
Author(s):  
Jorge Revez
Keyword(s):  
Information System ◽  
Information Systems ◽  
Qualitative Methodology ◽  
Science And Technology ◽  
Point Of View ◽  
Research Information ◽  
Research Information System ◽  
Science Management ◽  
Definition Of ◽  
The Relationship

Objective - The CRIS (Current Research Information System) systems implemented in Portugal are discussed and the role that libraries have played in the development of these information systems is sought. Methodology - A qualitative methodology was adopted through the study of two cases, providing a point of view on the relationship between libraries and researchers in science and technology. Results - The increasingly significant presence of CRIS systems in Portugal stands out but with a timid participation of libraries in their implementation and development process. Discussion - The relevance of libraries in new information contexts, the definition of science management policies that consider the context and the various actors involved in the development of information systems and the effectiveness of national coordination structures that organize information of researchers in science and technology are discussed. Limitations - The data obtained are partial and of a secondary nature. Originality - An unprecedented point of view is provided on the relationship in Portugal between the scientific community and libraries as information and support services for the organization of science. Objetivo – Abordam-se os sistemas CRIS (Current Research Information System) implementados em Portugal e procura-se conhecer o papel que as bibliotecas têm desempenhado no desenvolvimento destes sistemas de informação. Metodologia – Foi adotada uma metodologia qualitativa, através do estudo de dois casos, fornecendo um ponto de vista sobre a relação entre as bibliotecas e os investigadores em ciência e tecnologia. Resultados – Destaca-se a presença cada vez mais significativa dos sistemas CRIS em Portugal mas uma participação tímida das bibliotecas no seu processo de implementação e desenvolvimento. Discussão – Problematiza-se a relevância das bibliotecas nos novos contextos informacionais, a definição de políticas de gestão da ciência que considerem o contexto e os diversos atores envolvidos no desenvolvimento de sistemas de informação e a eficácia das estruturas de coordenação nacional que organizam a informação relativa aos investigadores em ciência e tecnologia. Limitações – Os dados obtidos são parcelares e de natureza secundária. Originalidade – É fornecido um ponto de vista inédito sobre a relação existente em Portugal entre a comunidade científica e as bibliotecas enquanto serviços de informação e de suporte à organização da ciência.

Federal Government Homeland Security Information Systems

2010 ◽  
pp. 93-111
Author(s):  
Christopher G. Reddick
Keyword(s):  
Data Mining ◽  
Information Technology ◽  
Information Systems ◽  
Federal Government ◽  
Homeland Security ◽  
Security Policy ◽  
Terrorist Attack ◽  
Department Of Homeland Security ◽  
Security Information ◽  
Definition Of

This chapter focuses on Homeland Security Information Systems (HSIS) in the federal government. One definition of HSIS, in the federal government, is the application of information technology to homeland security with the aim of detecting fragmented clues, assembling them as a puzzle, then using the information to stop a terrorist attack (Nunn, 2005). Nunn’s definition focuses on the use of information for data mining for deducing possible terrorist attacks and responses to these incidents. This chapter recognizes the importance of data analysis, but uses a broader definition of federal HSIS being the use of information systems to prepare for and respond to a terrorist attack or significant national emergency. This definition of HSIS covers the importance of data mining to discover how information fits together as pieces of the puzzle, but it also incorporates other elements of information technology (IT) that are used to respond and prepare for a national incident. This chapter will first examine the Department of Homeland Security which has a tremendous influence over homeland security policy and information systems in the United States. There is an examination in this chapter of the environmental context of HSIS in the federal government, demonstrating some of the important pieces of legislation that have an influence in this area. This chapter discusses the roles and responsibilities of federal government Chief Information Officers (CIOs) to discern the scope of their responsibilities. A section of this chapter examines some principles of effective IT management in federal agencies. The final part of this chapter provides the results of a survey of CIOs in federal government departments/agencies to determine the influence of HSIS on their organizations.

UNCERTAINTY MEASURE OF ROUGH SETS BASED ON A KNOWLEDGE GRANULATION FOR INCOMPLETE INFORMATION SYSTEMS

2008 ◽  
Vol 16 (02) ◽  
pp. 233-244 ◽  
Author(s):  
JUNHONG WANG ◽  
JIYE LIANG ◽  
YUHUA QIAN ◽  
CHUANGYIN DANG
Keyword(s):  
Information Systems ◽  
Incomplete Information ◽  
Rough Set ◽  
Rough Sets ◽  
Rough Set Theory ◽  
Computer Applications ◽  
Mathematical Tool ◽  
Uncertainty Measure ◽  
Definition Of ◽  
Incomplete Information Systems

Rough set theory is a relatively new mathematical tool for computer applications in circumstances characterized by vagueness and uncertainty. In this paper, we address uncertainty of rough sets for incomplete information systems. An axiom definition of knowledge granulation for incomplete information systems is obtained, under which a measure of uncertainty of a rough set is proposed. This measure has some nice properties such as equivalence, maximum and minimum. Furthermore, we prove that the uncertainty measure is effective and suitable for measuring roughness and accuracy of rough sets for incomplete information systems.

scholarly journals Applications of Matrices to a Matroidal Structure of Rough Sets

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Jingqian Wang ◽  
William Zhu
Keyword(s):  
Data Mining ◽  
Information Systems ◽  
Equivalence Relation ◽  
Rough Sets ◽  
Linear Independence ◽  
Matrix Representation ◽  
Attribute Reduction ◽  
Vector Spaces ◽  
Efficient Tool ◽  
Incidence Matrices

Rough sets provide an efficient tool for dealing with the vagueness and granularity in information systems. They are widely used in attribute reduction in data mining. There are many optimization issues in attribute reduction. Matroids generalize the linear independence in vector spaces and are widely used in optimization. Therefore, it is necessary to integrate rough sets and matroids. In this paper, we apply matrices to a matroidal structure of rough sets through three sides, which are characteristics, operations, and axioms. Firstly, a matroid is induced by an equivalence relation, and the matroid is a representable matroid whose representable matrix is a matrix representation of the equivalence relation. Then some characteristics of the matroid are presented through the representable matrix mainly. Secondly, contraction and restriction operations are applied to the matroid through the representable matrix and approximation operators of rough sets. Finally, two axioms of circuit incidence matrices of 2-circuit matroids are obtained, where 2-circuit matroids are proposed based on the characteristics of the matroid. In a word, these results show an interesting view to investigate the combination between rough sets and matroids through matrices.

scholarly journals Matroidal Structure of Rough Sets Based on Serial and Transitive Relations

2012 ◽  
Vol 2012 ◽  
pp. 1-16 ◽  
Author(s):  
Yanfang Liu ◽  
William Zhu
Keyword(s):  
Machine Learning ◽  
Data Mining ◽  
Rough Sets ◽  
Linear Independence ◽  
Algorithm Design ◽  
Vector Spaces ◽  
Transitive Relation ◽  
Upper Approximation ◽  
The Family ◽  
Lower And Upper Approximations

The theory of rough sets is concerned with the lower and upper approximations of objects through a binary relation on a universe. It has been applied to machine learning, knowledge discovery, and data mining. The theory of matroids is a generalization of linear independence in vector spaces. It has been used in combinatorial optimization and algorithm design. In order to take advantages of both rough sets and matroids, in this paper we propose a matroidal structure of rough sets based on a serial and transitive relation on a universe. We define the family of all minimal neighborhoods of a relation on a universe and prove it satisfies the circuit axioms of matroids when the relation is serial and transitive. In order to further study this matroidal structure, we investigate the inverse of this construction: inducing a relation by a matroid. The relationships between the upper approximation operators of rough sets based on relations and the closure operators of matroids in the above two constructions are studied. Moreover, we investigate the connections between the above two constructions.

scholarly journals ON AN INFORMATION APPROACH TO SOIL CLASSIFICATION

2012 ◽  
pp. 4-24
Author(s):  
V. A. Rozhkov
Keyword(s):  
Information Systems ◽  
Soil Classification ◽  
Scientific Discipline ◽  
Information Approach ◽  
Knowledge Based ◽  
Functional Scheme ◽  
Definition Of ◽  
Relationship Of ◽  
The Relationship

Under discussion are concepts of a new universal scientific discipline - informaciology, its principles, methods and approaches to elaborating the soil classifications. A formalized definition of the classification concept is given as a knowledge-based one in information systems. From viewpoint of classiology the concept of classification is of two kinds by nature being subdivided into taxonomy and meronomy. Taxonomy assumes the relationship between any classification object and a lot formed by it, whereas meronomy - the relationship of the total object to its parts. Accordingly relationships of equivalence in taxonomy and tolerance in meronomy are used. A structural-functional scheme of the system is presented to realize an information approach to soil classification.

scholarly journals INCREMENTALLY UPDATING APPROXIMATION IN INCOMPLETE INFORMATION SYSTEMS UNDER THE VARIATION OF OBJECTS

2020 ◽  
Vol 36 (4) ◽  
pp. 365-379
Author(s):  
Tran Thi Thanh Huyen ◽  
Le Ba Dung ◽  
Nguyen Do Van ◽  
Mai Van Dinh
Keyword(s):  
Information System ◽  
Information Systems ◽  
Rough Set ◽  
Rough Sets ◽  
Membership Functions ◽  
Approximation Space ◽  
The Third ◽  
Incomplete Information Systems ◽  
The Relationship ◽  
Over Time

Rough membership functions in covering approximation space not only give numerical characterizations of covering-based rough set approximations, but also establish the relationship between covering-based rough sets and fuzzy covering-based rough sets. In this paper, we introduce a new method to update the approximation sets with rough membership functions in covering approximation space. Firstly, we present the third types of rough membership functions and study their properties. And then, we consider the change of them while simultaneously adding and removing objects in the information system. Based on that change, we propose a method for updating the approximation sets when the objects vary over time.

scholarly journals Approximations of ∈ , ∈ ∨ q k -Fuzzy Hyperideals in Ordered LA-Semihypergroups

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Nabilah Abughazalah ◽  
Naveed Yaqoob ◽  
Samavia Ashraf
Keyword(s):  
Fuzzy Sets ◽  
Rough Sets ◽  
Lower Approximation ◽  
Upper Approximation ◽  
The Relationship

This paper concerns the relationship between rough sets, ∈ , ∈ ∨ q k -fuzzy sets, and the LA-semihypergroups. We proved that the lower approximation ( l -approx) and the upper approximation ( u -approx) of different hyperideals of LA-semihypergroups become again hyperideal and also provided some examples. We also provided a result which shows that, if ϑ is not a hyperideal of an LA-semihypergroup P , then its lower approximation is also not a hyperideal.

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