다각형 구간 타입-2 퍼지집합을 이용한 퍼지 공학시스템의 신뢰도 분석

조상엽 한국지식정보기술학회 2022 한국지식정보기술학회 논문지 Vol.17 No.5

공학시스템을 운영하는 경우 사용자의 실수, 입력 오류, 입력 데이터의 불확실성 등에 의해 신뢰도가 떨어지는 출력을 생산하게 된다. 이러한 문제를 제어하기 위한 방법은 시스템의 구성요소의 신뢰도를 반영하여 전체 공학시스템이 신뢰도를 출력에 반영하는 것이다. 본 논문에서는 공학시스템의 신뢰도를 평가하기 위하여 퍼지집합 이론을 기반으로 신뢰도를 계산하는 방법을 사용한다. 퍼지집합의 종류에는 소속값을 실수로 표현하는 전통적인 퍼지집합, 과 소속값을 구간으로 표현하는 직관퍼지집합, 구간으로 표현되는 소속값의 상한은 1로 고정하고 하한을 λ로 표현하는 수준 (λ,1) 구간값 퍼지집합, 불확정성을 표현할 수 있는 뉴트로소픽 집합, 다양한 퍼지집합을 표현하기 위한 다각형 타입-1 퍼지집합, 전통적인 퍼지지합의 소속값을 소속함수로 표현하는 타입-2퍼지집합 등이 제안되었다. 본 연구에서 우리는 다각형 구간 타입-2 퍼지집합을 이용하여 공학시스템의 신뢰도를 평가하는 방법을 제안한다. 구간 타입-2 퍼지집합은 이차 소속값이 모두 1과 같은 값을 가진다. 다각형 구간 타입-2 퍼지집합은 하한 소속함수와 상한 소속함수가 다각형으로 표현된다. 그러므로 기존의 퍼지집합들 보다 더 다양한 모양의 퍼지집합을 표현하는 것이 가능하게 된다. In the case of operating the engineering systems, the low reliable output of the systems may produced due to users error, input error, uncertainty of input data, etc. The way to overcome these problem is that the reliability of the entire engineering systems is reflected in the output by reflecting the reliability of the components of the systems. In this paper, in order to analyze the reliability of the engineering systems, we use the fuzzy set theory for calculating the reliability. The fuzzy sets have various types of sets such as the conventional fuzzy sets that represents the degree of membership as a real number, the intuitive fuzzy sets that expresses the degree of membership as an interval, the level (λ,1) interval valued fuzzy set that describe the upper bound of interval is fixed at 1 and the lower bound represent λ, the neutrosophic sets that can express the indeterminacy, the polygonal type-1 fuzzy sets that can describe various shape of conventional fuzzy sets, the type-2 fuzzy sets that represent the membership degree of conventional fuzzy sets as the membership function. In this study, we propose a method to analysis the reliability of engineering systems using polygonal interval type-2 fuzzy sets. In the interval type-2 fuzzy sets, secondary grades are all equal to 1. In the polygon interval type-2 fuzzy sets, the lower membership function and the upper membership function are expressed as polygons. Therefore, it becomes possible to represent fuzzy sets of more various shapes than the conventional fuzzy sets.

가중 퍼지 Pr/T 네트를 이용한 가중 퍼지 추론

조상엽 한국정보처리학회 2003 정보처리학회논문지. 소프트웨어 및 데이터 공학 Vol.10 No.7

Reliability Analysis of Systems Using Single Valued Neutrosophic Sets

조상엽 한국지식정보기술학회 2015 한국지식정보기술학회 논문지 Vol.10 No.4

In this paper we propose a new method to evaluate the reliability of systems based on the neutrosophic sets. Neutrosophic set is a part of neutrosophy which is able to deal with the nature of neutralities. There are many various studies to compute the reliability of systems such as fuzzy sets, interval valued fuzzy sets, intuitionistic fuzzy sets, etc. In fuzzy sets the degree of membership of a fuzzy set represented by a real number between zero and one. Sometimes the degree of membership itself may has the uncertainty and the vagueness. To deal this problem the concept of interval valued fuzzy sets was introduced which resolve the uncertainty of the degree of membership for fuzzy sets. In some applications we need to consider the truth membership to supported by the evidence and the falsity membership against by the evidence. To capture the this concept intuitionistic fuzzy sets was proposed. Intuitionistic fuzzy sets are able to only handle the incompleteness of information not the indeterminacy of information. In neutrosophic sets the concept of indeterminacy is included explicitly as truth membership, indeterminacy membership, and falsity membership. These three components of neutrosophic sets are independent. Therefore we can use the neutrosophic set as the generalized formal framework which generalizes the concept of the classic set, fuzzy set, interval valued fuzzy set, intuitionistic set, etc. The method proposed in the paper may be used to analyze the reliability of systems in various application domains include the concept of indeterminacy.

페트리네드를 이용한 규칙베이스의 검증

조상엽,Jo, Sang-Yeop 한국정보처리학회 1997 정보처리논문지 Vol.4 No.2

생성규칙(Produstion rule)전문가시스템에서 전문가의 전문지식((expertise)를 표현 하는 지식표현방법이다. 본 논문에서는 페트리네트(Petri-net)를 규칙베이스를 모형화하고, 규칙베이스 검증을 위해 페트리네트가 가지고 있는 체계적이고 구조적인 속성을 이용하여 규칙베이스(rule base)의 무결성(integrity)를 검증하는 방법을 제안한다. 이프러시져는 규칙베이스를 지역적 및 전역적 내부검증을 수행한다. The knowledge repressenatation technique by production rule has been popular method to represent to represent the experts'dxpertise in expert systems.In this paper,we propose a method to verify the integrity of rule base.Proposcd method models rule base as a Petri net and utilizes the systematic strucutural properties of the petri net for berifi-cation.We describe the pricesure to check rule base at both local and global level intermal verification.

Reliability Analysis of Systems Using Interval Valued Neutrosophic Sets

조상엽 한국지식정보기술학회 2015 한국지식정보기술학회 논문지 Vol.10 No.5

There are many various methods to deal with the reliability of systems. Fuzzy set theory is the one of the methods in order to evaluate the reliability of systems. In the fuzzy set theory the membership degree is represented by real number, where ∈ . Sometimes the membership degree of the fuzzy sets can not be represented by real number because of the membership degree itself may has the vagueness. To resolve the this problem the interval valued fuzzy sets are introduced. In the interval valued fuzzy sets the membership degree is represented by interval, where ⊆ . In some domains we need the concept of the truth membership function to supported by the evidence and the falsity membership function against by the evidence, where , ∈ . In order to deal with these the intuitionistic fuzzy sets are proposed. The classic sets, the fuzzy sets, the interval valued fuzzy sets, and the intuitionistic sets are able to only capture the concept of the incompleteness not the indeterminacy of information. In this study we propose a new way to evaluate the reliability of systems based on the interval neutrosophic sets. The interval neutrosophic set is a part of the neutrosophic sets which are able to deal with the nature of neutralities. In the interval neutrosophic sets these are consisted of three components such as truth membership function , indeterminacy membership function , and falsity membership function . , , ⊆ . Therefore we can manipulate the indeterminacy based on the indeterminacy membership function of the interval neutrosophic sets. The proposed method may be used to analyze the reliability of systems which have the concept of the indeterminacy.

경제·사회 시스템 보호를 위한 정보보안 정책 및 대응방안 수립

조상엽,이동은 한국지식정보기술학회 2009 한국지식정보기술학회 논문지 Vol.4 No.1

We need to make high degree of plans for stability and security measures urgently because the Internet becomes the core tool of the adminstration of nation, industries, and lives. Therefore we make that the information security policies should be approached as the view of protecting economic and social systems of nation and established the policies and the response plans to strengthen the basis of information security such as establishment of security organizations, build of security systems, development of security technologies, enlargement of information security investment, improvement of various related laws, cultivation of man powers, etc. in the areas of nation, enterprises, and individuals.

가중 퍼지 Pr/T 네트를 이용한 가중 퍼지 추론

조상엽,Cho, Sang-Yeop 한국정보처리학회 2003 정보처리학회논문지B Vol.10 No.7

본 논문에서는 가중 퍼지 Pr/T 네트에 기반을 둔 규칙기반시스템을 위한 가중 퍼지 추론알고리즘을 제안한다. 이때 퍼지 생성규칙의 확신도, 규칙에 나타나는 술어의 진리값과 술어의 중요도를 나타내는 가중값을 퍼지 숫자로 표현한다. 제안한 추론알고리즘은 퍼지 생성규칙에 있는 술어의 중요도에 따라 부여한 가중값을 이용하여 추론하기 때문에 $\circled1$ 술어의 가중값 없이 퍼지 생성규칙의 확신도만을 기반으로 단순하게 min과 max 연산을 하거나[10], $\circled2$ 술어의 가중값 없이 퍼지 생성규칙에 있는 퍼지 개념에 따라 믿음값 평가함수로 퍼지 생성규칙의 믿음값을 평가하는[12] 방법보다 더 유연하고 사람의 직관과 추론에 가깝다. This paper proposes a weighted fuzzy reasoning algorithm for rule-based systems based on weighted fuzzy Pr/T nets, where the certainty factors of the fuzzy production rules, the truth values of the predicates appearing in the rules and the weights representing the importance of the predicates are represented by the fuzzy numbers. The proposed algorithm is more flexible and much closer to human intuition and reasoning than other methods : $\circled1$ calculate the certainty factors using by the simple min and max operations based on the only certainty factors of the fuzzy production rules without the weights of the predicates[10] : $\circled2$ evaluate the belief of the fuzzy production rules using by the belief evaluation functions according to fuzzy concepts in the fuzzy rules without the weights of the predicates[12], because this algorithm uses the weights representing the importance of the predicates in the fuzzy production rules.

구간값 퍼지집합 추론의 퍼지 Pr/T 네트 표현

조상엽,Cho, Sang-Yeop 한국정보처리학회 2002 정보처리학회논문지B Vol.9 No.6

본 논문에서는 구간값 퍼지집합 추론의 퍼지 Pr/T 네트 표현을 제안한다. 여기에서 퍼지생성규칙은 지식표현을 위해 사용하고, 퍼지생성규칙의 믿음값은 구간값 퍼지집합으로 표현한다. 제안한 구간값 퍼지집합 추론 알고리즘은 퍼지생성규칙의 전제부와 결론부에 있는 퍼지개념에 따라서 적절한 믿음값평가함수를 사용하기 때문에 다른 방법보다 사람이 사용하는 직관과 추론에 더 가깝다. This paper proposes a fuzzy Pr/T net representation of interval-valued fuzzy set reasoning, where fuzzy production rules are used for knowledge representation, and the belief of fuzzy production rules are represented by interval-valued fuzzy sets. The presented interval-valued fuzzy reasoning algorithm is much closer to human intuition and reasoning than other methods because this algorithm uses the proper belief evaluation functions according to fuzzy concepts in fuzzy production rules.

단일값 뉴트로소픽 다중집합을 이용한 시스템의 신뢰도 분석

조상엽 한국지식정보기술학회 2017 한국지식정보기술학회 논문지 Vol.12 No.2

Neurotrophic sets are representation of indeterminacy that is difficult to express in classical sets, fuzzy sets, interval valued fuzzy sets, intuitionistic fuzzy sets, interval intuitionistic fuzzy sets, and so on. Neurotrophic sets are defined on the real standard and nonstandard subsets of . For this reason, it is difficult for the neurotrophic sets to actually apply in real science and engineering area. Therefore, many researchers have proposed subclasses of neurotrophic sets that can solve real world problems. These neurotrophic sets include single valued neurotrophic sets, interval valued neurotrophic sets, simplified neurotrophic sets, and single valued neutrosophic multisets. In this paper, we propose a method for evaluating the reliability of systems using single valued neurotropihc multisets. Single valued neurotrophic multisets are class of neurotrophic sets representing single valued neurotrophic sets and multisets concept together to provide a way to handle multiple sets of indeterminacy. This method can be applied to evaluate the reliability of systems having membership values represented by a single-value neurotropihc multiple set that is difficult to express in single valued neurotrophic sets, interval valued neurotropihc sets, and simplified neurotrophic sets.

사다리꼴 퍼지 뉴트로소픽 집합을 이용한 시스템의 신뢰도 분석

조상엽 한국지식정보기술학회 2016 한국지식정보기술학회 논문지 Vol.11 No.3

One of the most important thing in developing new systems makes the model of reliability for the systems. In real world it is difficult to evaluate the correct probabilities because of incorrect and uncertain data produced by human. To solve the these problems the fuzzy theory is applied to analysis of system reliability. In fuzzy sets, interval valued fuzzy sets, and intuitionistic fuzzy sets, the membership degrees are represented by single real value, interval value, and truth membership value and falsity membership value respectively. But these fuzzy set theories have demerit that there are no way to evaluate the indeterminacy for components of systems. The neutrosophic sets can provide the method to deal with the indeterminacy. In this research we propose the way to evaluate the reliability of systems based on trapezoidal fuzzy neutrosophic sets. The trapezoidal fuzzy neutrosophic sets has the indeterminacy membership function which can process the indeterminacy of systems. In the trapezoidal fuzzy neutrosophic sets, the membership degrees are represented by the trapezoidal shape and then they has efficiency to calculate the membership degrees and generality to include the representation of the triangle fuzzy neutrosohpic sets. The proposed method may use to compute the reliability of systems in various application domains.