• Journal of KIISE:Computer Systems and Theory
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• v.36 no.2
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• pp.87-93
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• 2009

Intrusion tolerant system enables essential services to maintain for a period of time under system failure, malicious attacks and is gaining more importance in national defense, communication infrastructure, and financial sector. However, few objective evaluation criteria for companies and agencies to introduce an appropriate system are available. This paper proposes a suitability evaluation method, using Analytic hierarchy process and fuzzy integral, for intrusion tolerant system, along with evaluation criteria which considers the characteristics and costs of systems in addition to other factors.

• Journal of Intelligence and Information Systems
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• v.15 no.3
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• pp.151-165
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• 2009

Fuzzy neural network is an integrated model of artificial neural network and fuzzy system and it has been successfully applied in control and forecasting area. Recently ANFIS(Adaptive Network-based Fuzzy Inference System) has been noticed widely among various fuzzy neural network models because of its outstanding accuracy of control and forecasting area. We design a new classification model based on ANFIS and evaluate it in terms of classification accuracy. We identified ANFIS-based classification model has higher classification accuracy compared to existing classification model, C5.0 decision tree model by comparing their experimental results.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.17 no.2
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• pp.131-140
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• 2004

It really needs fuzzy decision making of integrity assessment considering about both durability and load carrying capacity for maintenance and administration, such as repairing and reinforcing. This thesis shows efficient models about reinforced concrete structure using CART-ANFIS. It compares and analyzes decision trees parts of expert system, using the theory of fuzzy, and applying damage & diagnosis at reinforced concrete structure and decision trees of integrity assessment using established artificial neural. Decided the theory of reinforcement design for recovery of durability at damaged concrete ＆ the theory of reinforcement design for increasing load carrying capacity keep stability of damage and detection. It is more efficient maintenance and administration at reinforced concrete for using integrity assessment model of this study and can carry out predicting cost of life cycle.

• Journal of Environmental Impact Assessment
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• v.5 no.1
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• pp.47-60
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• 1996

Nitrate contamination problems from groundwater supplies have been reported throughout many countries in the world, including Korea. Nitrate salts can induce methemoglobinemia and possibly human gastric cancer. To reduce human health risk from nitrate in groundwater supplies, several nitrate risk-management strategies can be developed based on the acceptable level of human health risk, the reasonableness of nitrate-control cost, and the technical feasibility of nitrate-control methods. However, due to a lack of available information, assessing risk, cost and technical feasibility contains elements of uncertainty. In the present paper, a nitrate risk-management methodology using fuzzy sets in combination with a multiobjective decision-making (MODM) technique is developed to assist decision makers in evaluating, with uncertain information, various nitrate risk-management strategies in order to decide a proper strategy.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.05a
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• pp.407-408
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• 2003

다중입력조건에 따른 단일 출력퍼지시스템인 인구밀도와 도로조건에 따른 소개속도의 모델링시스템에서는 인구밀도와 도로조건의 퍼지멤버쉽에 대한 소개속도의 상승작용을 확인할 수 있었다. 그러나 도로조건을 평가하는 방법을 포장과 비포장으로만 구분함으로 인해 발생하는 퍼지추론과정에서 비탄력성은 향후 도로조건에 대한 세밀한 조사를 통하여 퍼지멤버쉽함수의 형태를 재고해야 할 것으로 판단된다. 실제 원자력시설에서 발생할 수 있는 사고의 경우 방사능에 노출될 수 있는 일반대중은 방사능에 대한 깊은 지식을 가지지 못하는 경우가 대부분이다. 따라서 차폐효과 혹은 소개속도를 정량적으로 파악하기 힘든 경우가 많다. 따라서, 이러한 퍼지시스템은 방사선 비상대응 시스템을 개발하는 의사결정자나 비상시 방사능에 노출되는 사람들의 대응 방식을 모델링하는데 유용할 것으로 판단된다.

• Journal of the Korea Society of Computer and Information
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• v.10 no.1 s.33
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• pp.133-140
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• 2005

If a Player car precedes from start to the end or a fuzzy car wins every day during computer or racing games, most players will lose their interest in the games soon after several times. In order to solve this Problem and increase amusement at racing games, the more important thing than anything else is decide the ranking. In this thesis, in order to give amusement In racing games, the researcher made a fuzzy car and made it race with player cars. Because the preceding fuzzy car runs ahead of player cars, it can recognize their behaviors according to change of following player cars' speed and distance, and the fuzzy car changes its memory, but doesn't enforce actual behaviors. If the fuzzy car would make decision, it has to do behaviors to compete the ranking on the basis of the contracts it has memorized under the situation where a timer is awarded. In addition, although an accompanying fuzzy car has different contents of memory, it is operated in the same way as mentioned above. At the time of experiments, the researcher applied the actual value to the test program and drew result for ranking competition. In conclusion, the researcher could confirm that we can have modeling of various behaviors by means of the method using fuzzy logic rather than simple if-then method.

• Journal of Intelligence and Information Systems
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• v.12 no.3
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• pp.15-32
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• 2006

The increasing complexity of the socio-economic environments makes it less and less possible for single decision-maker to consider all relevant aspects of problem. Therefore, many organizations employ groups in decision making. In this paper, we present a multiperson decision making method using fuzzy logic with linguistic quantifier when each of group members specifies imprecise judgments possibly both on performance evaluations of alternatives with respect to the multiple criteria and on the criteria. Inexact or vague preferences have appeared in the decision making literatures with a view to relaxing the burdens of preference specifications imposed to the decision-makers and thus taking into account the vagueness of human judgments. Allowing for the types of imprecise judgments in the model, however, makes more difficult a clear selection of alternative(s) that a group wants to make. So, further interactions with the decision-makers may proceed to the extent to compensate for the initial comforts of preference specifications. These interactions may not however guarantee the selection of the best alternative to implement. To circumvent this deadlock situation, we present a procedure for obtaining a satisfying solution by the use of linguistic quantifier guided aggregation which implies fuzzy majority. This is an approach to combine a prescriptive decision method via a mathematical programming and a well-established approximate solution method to aggregate multiple objects.

• Proceedings of the Korean Statistical Society Conference
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• 2001.11a
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• pp.99-104
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• 2001

본 연구의 주된 목표는 1997년 주가자료를 데이터마이닝 기법인 로지스틱모형, 의사결정트리, 신경망, SVM(support vector machine), 뉴로퍼지모형을 사용하여 분석한 후 우리나라 경제상황을 진단하고 예측하는데 가장 적합한 모형을 찾고 그 모형을 해석하는데 있다. 1997년 주가자료를 훈련자료로 간주하여 그 당시 경제 상황에 따라 적절한 구간으로 나누고 훈련시킨 결과 중요한 변수로는 주가지수, 등락률 10일 이동분산, 10일 이동분산의 변동비로 나타났으며 적절한 기법으로는 의사결정트리, 신경망, SVM임을 알 수 있다. 1997년 이외의 주가자료를 데이터마이닝 기법(신경망, 의사결정트리, SVM)에 적용한 결과, 우리나라 경제상황을 고려해 볼 때 신경망이 가장 정확도가 좋은 기법으로 보여진다.

• Journal of Intelligence and Information Systems
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• v.4 no.1
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• pp.59-77
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• 1998

정보의 중요성과 함께 컴퓨터를 중심으로 급속하게 발전한 정보기술은 정보를 가공하고 의사결정에 도움을 주며 전략적 차원에서 우위를 가지게 하는 역할을 하였고 조직의 구조를 근본적으로 개편하였다. 이로 인해 새로운 개념인 '가상기업'을 창출하였다. 본 논문은 정보화 사회에 기업의 경쟁력을 극대화할 것으로 예상되는 가상기업의 모델을 제시하고 실제적인 가상기업 구축방법을 제시하는 목적이 있다. 먼저 아직 초기 단계의 개념인 가상기업의 개념 정립을 위해 인터넷 자료와 문헌 연구를 통하여 가상기업에 대한 모델을 제시하였고 모델에서는 기존 연구들을 종합하여 가상기업의 정의를 내리고 정의를 중심으로 특징과 단점을 제시하였다. 다음으로 퍼지이론을 응용하여 가상기업의 구축방법을 제시하였다. 구축방법으로는 퍼지이론이 크게 세 부분에 적용이 된다. 첫째로 퍼지이론이 사용되는 부분은 현재의 업무를 분석하여 기존의 업무와 유사성을 찾는 작업이다. 분석된 업무를 통해 제시된 기준을 이용하여 기존의 업무와 유사한 성격을 가진 기존 업무를 찾고 이 업무를 효과적으로 수행 한 팀들을 찾는 작업이 이루어진다. 둘째로 각 팀의 능력을 상대적으로 평가하는 방법에 퍼지 Rank Ordering 방법을 사용한다. 여러 팀이 기존의 업무를 수행한 결과 나타날 때 각 팀의 이번 업무에서 요구하는 기준에 상대적으로 만족하는 정도를 파악한다. 마지막으로 퍼지 종합적 평가 방법을 이용하여 가상조직의 업무에 적절한 팀을 찾아내는 작업을 한다.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.41
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• pp.41-50
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• 1997

In this paper, we presents the method for finding the compensatory solution for fuzzy multiobjective nonlinear programming problem with fuzzy parameters involved in the problem-formulation process and fuzzy equal goals of the decision maker for each of the objective functions. The fuzzy parameters in the objective functions and the constraints characterized by fuzzy numbers. The proposed method can be applied to case with multiobjective problems and guarantee an efficient solution. An illustrative numerical example is presented.