• Journal of Navigation and Port Research
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• v.32 no.3
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• pp.167-172
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• 2008

The aim of this paper is to determine the replacement time of containerships in economical viewpoint. Especially, there was a lot of vagueness to the cost data for calculation of an economical life in a containership. For this, a fuzzy number used to express the vague nature about a cost data. This paper developed the fuzzy cost model using fuzzy numbers, and to analyze more practically than the existing cost model. And the proposal model used to decide the economical life about various kinds of containerships.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.241-242
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• 2007

This paper aims to determination of container ship's economical replacement policy by Fuzzy Annual Equivalent Cost Method Especially, though there was much vagueness to expense for calculation of container ship's economical life, this paper expressed such vague nature with a fuzzy number. And this paper developed the fuzzy expense model with a fuzzy number, and to analyze more practically than an expense model, was decided economical life-age with an application in a containership of various volumes.

• Proceedings of the Korea Information Processing Society Conference
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• 2018.10a
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• pp.457-459
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• 2018

지난 해 롤스로이스의 무인 선박 개발 프로젝트(AAWA) 본격화 등 선박과 관련된 무인 자동화 기술 개발이 활발해지면서 국내의 R&D 사업이 많이 증가하였다. 특히 국내에서는 퍼지 모델을 이용한 RVC 지능 시스템 등 퍼지 이론을 사용한 기술들이 최근까지도 발표되고 있다. 퍼지 모델을 결정하기 위해선 해당 시스템에 대한 전문 지실뿐만이 아니라 다양한 환경에서의 반복적인 실험과 수정을 필요로 하기 때문에 시뮬레이터를 만들어 실험하게 되는데 다양한 환경에서의 반복적인 실험과 수정을 필요로 하기 때문에 시뮬레이터를 만들어 실험하게 되는데 대부분의 연구에서 시뮬레이터가 제작되는 비용과 시간에도 불구하고 해당 퍼지 모델을 위해서만 쓰이게 된다. 따라서 본 논문에서는 다양한 환경에서 퍼지 모델을 반복 실험할 수 있도록 시뮬레이터를 개발하였으며 기존의 퍼지 모델 일부를 본 시뮬레이터에 적용하여 같은 실험을 할 수 있음을 보이고 이를 통해 퍼지 모델을 만드는데 드는 시간과 비용을 줄일 수 있음을 보였다.

• Korean Journal of Construction Engineering and Management
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• v.8 no.3
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• pp.159-167
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• 2007

In this study, the concepts of integrated VE analysis assessment is introduced in order to achieve "Design for Deterioration performance" in design VE phase. For this purpose, a framework for fuzzy reliability based LCC and value analysis model using fuzzy logic based approach for breakwaters Projects is suggested. It is anticipated that the methodology Proposed in this paper can also be utilized in the design and maintenance phase of other facilities where decision making is made for the fuzzy reliability based life cycle cost and value analysis.

• Journal of the Korean Institute of Intelligent Systems
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• v.6 no.2
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• pp.97-105
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• 1996

In this paper, an adaptive model predictive controller for nodinear processes using fuzzy model is proposed. Adaptive structure is implemented by recursive fuzzy modeling. The model and control law can be obtained the same as GPC, because the consequent parts of the fuzzy model comprise linear equations of input and output variables. The proposed Adaptive fuzzy model predictive controller (AFMPC) controls nonlinear process well due to the intrinsic nonlinearity of the fuzzy model. When AFMPC's output is variation in the process control input, it maintains zero steady-state offset for a constant reference input and has superior performance. The properties and performance of the proposed control scheme were examined with nonlinear plant by simulation.

• Korean Journal of Construction Engineering and Management
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• v.8 no.5
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• pp.71-79
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• 2007

It is common that the analysis of VE/LCC is performed in design phase of quay wall structures. The analysis is mainly executed based on experience and engineering sense of expert considering the selection of construction method, construction and maintenance cost. Recently there are increasing demands on the analysis that includes uncertainty and vulnerability of input parameters, for this purpose, fuzzy reliability based probabilistic VE/LCC analysis model for quay wall structures is suggested. In VE/LCC analysis for quay wall structures, the application of probabilistic analysis method give very similar results compare with those of deterministic analysis method. It is anticipated that the methodology proposed in this paper can also be utilized in the design and maintenance phase of other facilities where decision making is made for the probabilistic life cycle cost and value analysis.

• Korean Journal of Construction Engineering and Management
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• v.4 no.4 s.16
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• pp.201-211
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• 2003

Considering about construction projects characteristics, there Is an existing uncertainty which causes inaccuracy or invalidity under decision making situation. Therefore, cost risk analysis of numerous construction projects are Inclined to depend on expert's experiences and subjective judgements. In Korean domestic construction works, however, there is no reasonable method or process for applying subjective elements. Only probabilistic analysis using objective calculation are being used now. This research suggests a cost risk analysis method to analyze quantitatively Cost Impact by risk, and it appraises expert's subjective elements for the purpose of enhancing validity of cost estimation. Moreover, a new cost risk analysis method is introduced for providing convenient user interface in practical business.

• Journal of the Korean Institute of Intelligent Systems
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• v.7 no.5
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• pp.77-85
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• 1997

A new technique using integer programming based on fuzzy multi-criteria function is proposed for generator maintenance scheduling. Minimization of maintenance delay cost and maximization of supply reserve power are considered for fuzzy multi-criteria function To obtain an optimal solution for gen- ,:rator maintenance scheduling under fuzzy environment, fuzzy multi-criteria integer programming is )used. In the maintenance scheduling, a characteristic feature of the presented approach is that the crisp conaitraints with uncertainty can be taken into account by using fuzzy set theory and so more flexible solution Ian he obtained. The effectiveness of the proposed approach is demonstrated by the simulation results.

• Korean Journal of Cognitive Science
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• v.13 no.1
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• pp.13-21
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• 2002

Fuzzy logic ignores some information in the reasoning process. Neural network is powerful tools for the pattern processing, but, not appropriate for the logical reasoning. To model human knowledge, besides pattern processing capability, the logical reasoning capability is equally important. Another new neural network called neural logic network is able to do the logical reasoning. Because the fuzzy inference is a fuzzy logical reasoning, we construct fuzzy inference network based on the neural logic network, extending the existing rule-inference network. And the traditional propagation rule is modified. Experiments are performed to compare search costs by sequential searching and searching by priority. The experimental results show that the searching by priority is more efficient than the sequential searching as the size of the fuzzy inference network becomes larder and an the number of searching increases.

• Journal of Korean Society of Transportation
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• v.20 no.1
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• pp.65-76
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• 2002

This study is realized using fuzzy evaluation and AHP(the analytic hierarchy process) for the optimum search of traffic route and estimated by the quantitative analysis in the vague subjective judgement. It is different from classical route search and noticed thinking method of human. Appraisal element, weight, appraisal value of route is extracted from basic of the opinion gathering fur the driving expert and example of route model was used for the finding of practice utility. Model assessment was performed attribute membership function making of estimate element, estimate value setting, weight define by the AHP, non additive presentation of weight according to $\lambda$-fuzzy measure, Choquet fuzzy integral.