• Title/Summary/Keyword: approximate reasoning

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A Hybrid Approach Using Case-based Reasoning and Fuzzy Logic for Corporate Bond Rating

  • Kim, Hyun-jung;Shin, Kyung-shik
    • 한국지능정보시스템학회:학술대회논문집
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    • 한국지능정보시스템학회 2003년도 춘계학술대회
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    • pp.474-483
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    • 2003
  • A number of studies for corporate bond rating classification problems have demonstrated that artificial intelligence approaches such as Case-based reasoning (CBR) can be alternative methodologies to statistical techniques. CBR is a problem solving technique in that the case specific knowledge of past experience is utilized to find a most similar solution to the new problems. To build a successful CBR system to deal with human information processing, the representation of knowledge of each attribute is an important key factor We propose a hybrid approach of using fuzzy sets that describe the approximate phenomena of the real world because it handles inexact knowledge represented by common linguistic terms in a similar way as human reasoning compared to the other existing techniques. Integration of fuzzy sets with CBR is important to develop effective methods for dealing with vague and incomplete knowledge to statistical represent using membership value of fuzzy sets in CBR.

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수로교 개보수를 위한 개략공사비 산정 모델 개발 - 회귀분석과 사례기반추론의 비교를 중심으로 - (Development of Approximate Cost Estimate Model for Aqueduct Bridges Restoration - Focusing on Comparison between Regression Analysis and Case-Based Reasoning -)

  • 전건영;조재용;허영
    • 대한토목학회논문집
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    • 제33권4호
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    • pp.1693-1705
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    • 2013
  • 국내의 수로교는 쌀문화로 상징되는 농업용수를 공급하는 교량으로서 수로교를 개보수하기 위해서는 기본설계를 실시하는 것이 바람직하나 현재 생략되고 있는 실정이므로 이에 소요되는 공사비를 산정할 필요가 있다. 이 연구에서는 2003년 이후 교체한 RC구조 수로교에 대한 실적자료를 기초로 개략공사비 산정 회귀분석(RA) 모델과 사례기반추론(CBR) 모델을 개발하였다. RA 모델의 경우 단순회귀 모델이 다중회귀 모델보다 오차율이 낮았다. CBR 모델의 경우 유전 알고리즘을 이용하였으며 영향요인의 가중치, 편차, 순위조건을 최적화 대상으로 하였고 특히 영향요인 가중치의 범위를 제한하여 수로교 개보수 공사비의 예측 정확도를 제고하였다. RA 모델과 CBR 모델 사이의 오차율은 통계적 차이를 보이지 않았다. 본 논문에서 제시된 수로교 개보수 개략공사비 산정방법은 개보수사업의 시행에 따른 신속한 의사결정을 하는데 활용될 수 있을 것으로 기대된다.

퍼지생성규칙을 위한 퍼지페트리네트표현에서 후진추론 (Backward Reasoning in Fuzzy Petri - net Representation for Fuzzy Production Rules)

  • 조상엽
    • 한국정보처리학회논문지
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    • 제5권4호
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    • pp.951-958
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    • 1998
  • 본 논문에서는 퍼지생성규칙을 표현한 퍼지페트리네트에서 사용할 수 있는 후진추론 알고리즘을 제안한다. 퍼지페트리 네트워크표현은 근사추론 시스템을 모형화하거나 퍼지추론엔진을 구현하는데 사용할 수 있다. 본 논문이 제안한 알고리즘은 단순히 min과 max 게산만을 하는 기존의 알고리즘과는 달리 퍼지생성규칙의 전제부와 결론부에 퍼지개념의 유무에 따라 적절한 믿음값평가함수을 사용하여 보다 더 인간적인 추론을 한다. 후진추론 알고리즘은 목표노드에서 시작노드까지의 후진추론 통로를 구한 후에 믿음값평가함수를 이용하여 목표노드의 믿음값을 구한다.

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Psychological Jump in Vague Knowledge

  • Nakatsuyama, Mikio
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1998년도 The Third Asian Fuzzy Systems Symposium
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    • pp.343-346
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    • 1998
  • This paper deals with the decision in vague knowledge, One method is a classic theory. That is to say, constraints and goals in the vague knowledge. Another method is the fuzzy catastrophe. If there exist two fuzzy variables, there may be a discontinuity which plays an important role in decision.

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AN APPROXIMATE COST ESTIMATING MODEL FOR CONSTRUCTION PROJECTS

  • Daehee Lim;Seung-hoon Lee
    • 국제학술발표논문집
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    • The 3th International Conference on Construction Engineering and Project Management
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    • pp.1242-1247
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    • 2009
  • The sudden changes in the construction market and the progressively intensifying price wars have amplified the importance of the construction cost estimation in the initial and planning phases of construction projects. However the methodologies and process of estimating construction cost in the planning and design phase are not standardized in the domestic market, in contrast to the markets of more developed countries. Therefore this paper proposes a new approximate estimation model to be used from the initial stages of construction projects. This methodology that extracts, modifies and synthesizes comparable elements of previous cases. This will introduce the foundation for the implementation of systems with improved usability and applicability.

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Analyzing the compressive strength of clinker mortars using approximate reasoning approaches - ANN vs MLR

  • Beycioglu, Ahmet;Emiroglu, Mehmet;Kocak, Yilmaz;Subasi, Serkan
    • Computers and Concrete
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    • 제15권1호
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    • pp.89-101
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    • 2015
  • In this paper, Artificial Neural Networks (ANN) and Multiple Linear Regression (MLR) models were discussed to determine the compressive strength of clinker mortars cured for 1, 2, 7 and 28 days. In the experimental stage, 1288 mortar samples were produced from 322 different clinker specimens and compressive strength tests were performed on these samples. Chemical properties of the clinker samples were also determined. In the modeling stage, these experimental results were used to construct the models. In the models tricalcium silicate ($C_3S$), dicalcium silicate ($C_2S$), tricalcium aluminate ($C_3A$), tetracalcium alumina ferrite ($C_4AF$), blaine values, specific gravity and age of samples were used as inputs and the compressive strength of clinker samples was used as output. The approximate reasoning ability of the models compared using some statistical parameters. As a result, ANN has shown satisfying relation with experimental results and suggests an alternative approach to evaluate compressive strength estimation of clinker mortars using related inputs. Furthermore MLR model showed a poor ability to predict.

근사질의 응답기능을 이용한 협동적 사례기반추론 (Cooperative Case-based Reasoning Using Approximate Query Answering)

  • 김진백
    • 한국정보시스템학회지:정보시스템연구
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    • 제8권1호
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    • pp.27-44
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    • 1999
  • Case-Based Reasoning(CBR) offers a new approach for developing knowledge based systems. CBR has several research issues which can be divided into two categories : (1) static issues and (2) dynamic issues. The static issues are related to case representation scheme and case data model, that is, focus on casebase which is a repository of cases. The dynamic issues, on the other hand, are related to case retrieval procedure and problem solving process, i.e. case adaptation phase. This research is forcused on retrieval procedure Traditional query processing accepts precisely specified queries and only provides exact answers, thus requiring users to fully understand the problem domain and the casebase schema, but returning limited or even null information if the exact answer is not available. To remedy such a restriction, extending the classical notion of query answering to approximate query answering(AQA) has been explored. AQA can be achieved by neighborhood query answering or associative query answering. In this paper, neighborhood query answering technique is used for AQA. To reinforce the CBR process, a new retrieval procedure(cooperative CBR) using neighborhood query answering is proposed. An neighborhood query answering relaxes a query scope to enlarge the search range, or relaxes an answer scope to include additional information. Computer Aided Process Planning(CAPP) is selected as cooperative CBR application domain for test. CAPP is an essential key for achieving CIM. It is the bridge between CAD and CAM and translates the design information into manufacturing instructions. As a result of the test, it is approved that the problem solving ability of cooperative CBR is improved by relaxation technique.

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BIM/GIS 기반 도로 개략공사비 산정 프로토타입 연구 (Roadway Preliminary Cost Estimation Prototype based on BIM and GIS)

  • 박원영;강태경;이유섭
    • 한국건설관리학회논문집
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    • 제14권6호
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    • pp.14-21
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    • 2013
  • 완성된 도면과 시방서를 기초로 산출한 상세한 물량 정보를 토대로 상세 공사비를 예측하는 업무에 비해 도면과 시방서가 완성되기 이전 단계에서 시설제원이나 개략적인 설계 정보 등을 기초로 개략공사비를 예측하는 업무는 공사비 예측 업무 담당자의 주관적인 판단에 의존하는 경향이 크고 객관성이 낮은 실정이다. 본 연구에서는 도로건설공사 초기단계에서의 사업비 예측 모델을 연구하고 이를 토대로 건설공사 개략공사비 예측 시스템을 개발하였다. 이 시스템은 BIM 및 GIS를 이용하여 사업 초기단계 개략적인 노선선정에 따른 개략공사비 추정에 있어 사례기반추론을 기반으로 사업비 예측의 정확성 향상과 업무 선진화에 기여할 것으로 기대된다. 또한 사용자가 인터넷을 통해 편리하게 접근할 수 있고 객관적이면서 일관성 있는 개략공사비 예측 결과를 제공받을 수 있으므로 업무 투명성 측면의 효과도 기대할 수 있을 것이다.

여객선 기관실의 설계 옵션 평가를 위한 결정 지원 프레임 워크 (A Design Decision Support Framework for Evaluation of Design Options in Passenger Ship Engine Room)

  • 김수웅
    • 한국기계기술학회지
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    • 제13권2호
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    • pp.9-19
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    • 2011
  • Most real world design evaluation and risk-based decision support combine quantitative and qualitative (linguistic) variables. Decision making based on conventional mathematics that combines qualitative and quantitative concepts always exhibit difficulty in modelling actual problems. The successful selection process for choosing a design/procurement proposal is based on a high degree of technical integrity, safety levels and low costs in construction, corrective measures, maintenance, operation, inspection and preventive measures. In this paper, a design decision support framework using a composite structure methodology grounded in approximate reasoning approach and evidential reasoning method is suggested for design evaluation of machinery space of a ship engine room at the initial stages. An illustrative example is used to demonstrate the application of the proposed framework.