• 한국환경과학회지
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• 제8권4호
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• pp.533-538
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• 1999

Fuzzy algorithm of automatic control for dissolved oxygen(DO) concentration in the aeration tank of an activated sludge process is proposed. Among variables repirometry and air flowrate are selected as significant input factors and the relationship with DO is estimated using a multiple regression model. The DO concentration and the amount of repirometry are fuzzified and the fuzzy rule base are determined. Using the fuzzy algorithm, the change of amount of air flowrate are determined and the change of amount of DO is derived.

• 한국지능시스템학회논문지
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• 제17권4호
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• pp.546-549
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• 2007

When we deal with crisp data, it is common to find the correlation between variables. In this paper, we propose a method to calculate the correlation coefficient for intuitionistic fuzzy data, by adopting the concepts from the conventional statistics. The value of the correlation coefficient computed from our formula not only provides us the strength of the relationship of intuitionistic fuzzy sets, but also shows that the intuitionistic fuzzy sets are positively or negatively related.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제9권2호
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• pp.83-93
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• 2009

Recently, El-Naschie has shown that the notion of fuzzy topology may be relevant to quantum paretical physics in connection with string theory and E-infinity space time theory. In this paper, we study the concepts of r-fuzzy semi-I-open, r-fuzzy pre-I-open, r-fuzzy $\alpha$-I-open and r-fuzzy $\beta$-I-open sets, which is properly placed between r-fuzzy openness and r-fuzzy $\alpha$-I-openness (r-fuzzy pre-I-openness) sets regardless the fuzzy ideal topological space in Sostak sense. Moreover, we give a decomposition of fuzzy continuity, fuzzy ideal continuity and fuzzy ideal $\alpha$-continuity, and obtain several characterization and some properties of these functions. Also, we investigate their relationship with other types of function.

• 한국지능시스템학회논문지
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• 제11권7호
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• pp.649-652
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• 2001

In this paper, we introduce neighborhood systems in an L-fuzzy topology using complete MV-algebras. We investigate the relationship between L-fuzzy topologies and the neighborhood systems. We study the properties of neighborhood system.

• Journal of applied mathematics & informatics
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• 제7권1호
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• pp.195-203
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• 2000

In this paper, the concept of strongly p-Cesaro summability of sequences of fuzzy numbers is introduced. The relationship between statistical convergence and strongly p-Cesaro summability is discussed.

• 한국지능시스템학회논문지
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• 제22권1호
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• pp.114-118
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• 2012

본 연구는 시스템의 구조 인식에 유효한 FSM을 이용하여 기업프로젝트 성과요인에 대한 층별 구조는 알 수 있지만 각 층에 속해 있는 성과요인에 대한 층별 간의 관계에 대해서는 알 수 없다는 관점에서 퍼지시스템을 이용하여 기업프로젝트 성과요인의 층별 관계에 대한 구조를 분석하고자 한다. 최하층과 중간층, 중간층과 최상층과의 관계를 가능적인 면과 필연적인 면이 섞여 있는 형태의 기업프로젝트 평가모델을 이용하여 구한 퍼지관계행렬로서 퍼지관계분석을 행하고 그 유용성을 보였다.

• 한국지능시스템학회논문지
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• 제23권4호
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• pp.366-370
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• 2013

설명변수와 반응변수 사이의 통계적 관계를 설명하기 위해 사용되는 회귀모형을 분석하는 방법을 회귀분석이라 한다. 본 논문에서는 독립변수와 종속변수에 대한 퍼지관계를 표현하는 퍼지회귀모형를 추정하기 위하여 이상치에 민감하지 않은 로버스트한 추정량인 Theil방법을 소개한다. Theil방법은 설명변수와 반응변수의 ${\alpha}$-수준집합의 각 성분으로 구성된 집합에서 선택한 임의의 두 쌍 자료로부터 계산된 변화율의 중위수를 두 변수에 대한 변화량의 추정량으로 간주한다. 본 논문에서 제안된 Theil방법이 최소자승법을 이용하여 추정된 퍼지회귀모형보다 더 정확할 수 있음을 예제를 통하여 확인한다.

• 대한건축학회논문집:계획계
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• 제36권3호
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• pp.13-20
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• 2020

The purpose of this study is to analyze the fuzzy pattern that is reflected on the inside of the value evaluator in measuring the economic value of architectural aesthetic using the fuzzy-contingent valuation method. The main results of analyzing the relationship between architectural aesthetic and fuzzy patterns by typing 307 fuzzy patterns collected from visitors at Dongdaemun Design Plaza are as follows: First, low levels of architectural aesthetic can be a primary cause of extreme refusal of payment. However, it was confirmed that the extreme refusal of payment could partially involve mentality of free-ride on public goods or mentality that would not give value to past events that are not future. Second, if the architectural aesthetic score is 77.5, the most perfect form of fuzzy pattern is formed. It is confirmed that the fuzzy form, which is the standard in the relationship between architectural aesthetic and money value, is made at 77.5 points. This means that it is most efficient to have 77.5 points of architectural aesthetic to secure balanced data by membership in the study of architectural aesthetic value measurement through fuzzy pattern. Third, according to the architectural aesthetic score, respondents can be interpreted as follows: no monetary willingness arises before or after 52.4, starts to respond to the amount before and after 65.6, severe conflict over payments around 70.6~71.7, stronger willingness to pay around 77.6, want to pay for sure around 80.0.

• 산업경영시스템학회지
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• 제40권4호
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• pp.29-37
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• 2017

This papers focuses on remanufacturing processes in a closed loop supply chain. The remanufacturing processes is considered as one of the effective strategies for enterprises' sustainability. For this reason, a lot of companies have attempted to apply remanufacturing related methods to their manufacturing processes. While many research studies focused on the return rate for remanufacturing parts as a control parameter, the relationship with demand certainties has been studied less comparatively. This paper considers a closed loop supply chain environment with remanufacturing processes, where highly fluctuating demands are embedded. While other research studies capture uncertainties using probability theories, highly fluctuating demands are modeled using a fuzzy logic based ambiguity based modeling framework. The previous studies on the remanufacturing have been limited in solving the actual supply chain management situation and issues by analyzing the various situations and variables constituting the supply chain model in a linear relationship. In order to overcome these limitations, this papers considers that the relationship between price and demand is nonlinear. In order to interpret the relationship between demand and price, a new price elasticity of demand is modeled using a fuzzy based nonlinear function and analyzed. This papers contributes to setup and to provide an effective price strategy reflecting highly demand uncertainties in the closed loop supply chain management with remanufacturing processes. Also, this papers present various procedures and analytical methods for constructing accurate parameter and membership functions that deal with extended uncertainty through fuzzy logic system based modeling rather than existing probability distribution based uncertainty modeling.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제8권1호
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• pp.6-10
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• 2008

In this paper, we introduce the concept of fuzzy (r, s)-adherence points, fuzzy (r, s)-accumulation points and fuzzy (r, s)-derived sets in double fuzzy topology. We investigate some of their properties. The relationship with double fuzzy closure operator was studied.