• 대한기계학회논문집A
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• 제33권10호
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• pp.1171-1176
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• 2009

This paper provides how to establish an integrated plan for LE (life extension) and MD (modernization) of aged hydropower plants. The methodology is developed through review of overseas/domestic LE/MD histories, investigation of the previous overseas methodologies and consideration of domestic practices. The methodology includes reviews of the various factors such as condition, operation and maintenance history, up-to-date technology, and economic benefit. In order to establish the life extension/modernization plan, the methodology is applied to the domestic aged hydropower plants. Finally, priority rankings and draft practice plans for LE/MD are derived.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 추계학술발표회논문집(1)
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• pp.293-299
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• 1995

A methodology is applied to identify tile learning trend related to the safety and availability of U.S. commercial nuclear power plants. The application is intended to aid in reducing likelihood of human errors. To assure that tile methodology ran be easily adapted to various types of classification schemes of operation data, a data bank classified by the Transient Analysis Classification and Evaluation(TRACE) scheme is selected for the methodology. The significance criteria for human-initiated events affecting tile systems and for events caused by human deficiencies were used. Clustering analysis was used to identify the learning trend in multi-dimensional histograms. A computer rode is developed based on tile K-Means algorithm and applied to find the learning period in which error rates are monotonously decreasing with plant age.

• Nuclear Engineering and Technology
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• 제49권2호
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• pp.313-326
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• 2017

The systematic management of plant risk is crucial for enhancing the safety of nuclear power plants and for designing new nuclear power plants. Accident sequence precursor (ASP) analysis may be able to provide risk significance of operational experience by using probabilistic risk assessment to evaluate an operational event quantitatively in terms of its impact on core damage. In this study, an ASP methodology for two operation mode, full power and low power/shutdown operation, has been developed and applied to significant accident precursors that may occur during the operation of nuclear power plants. Two operational events, loss of feedwater and steam generator tube rupture, are identified as ASPs. Therefore, the ASP methodology developed in this study may contribute to identifying plant risk significance as well as to enhancing the safety of nuclear power plants by applying this methodology systematically.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.609-610
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• 2006

This paper introduces a methodology for construction of ontology-based product knowledge Map. For CPC(Collaborative Product Commerce) environment, engineering application of ontology has been studied . However, there are no generic and comprehensive methodologies for ontology construction yet because of such problems: dependency on experience of ontologist and domain experts and insufficiency of detail stages or rules. To solve those problems, we propose a methodology to construct ontology from engineering documents in semi-automatic. We use middle-out strategy and term's axioms, sub-definitions, to build ontology map. 5-turple ontology structure, semantic network and First order logic (FOL) are used for ontology definition in this study.

• 한국자동차공학회논문집
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• 제8권1호
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• pp.101-109
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• 2000

Occupant protection in the side impact of a car became one of the most important issues of car crashworthiness due to high injury level in a side impact crash. An accurate simulation of the side impact crash is an essential tool for the reduction of development time and cost for side impact safety system. This paper describes a new test methodology that can accurately generate the crash pulses of a vehicle and a door in a very cost-effective manner, and then evaluates the injury values of the dummy for the various sled pulses. This test methodology is simple and easy to approach because the door velocity is controlled by the hydraulic actuator and brake and the seat velocity is only adjusted by the friction force of the hydraulic brake. The superiority of the proposed test methodology is proven by the evaluation of dummy's injury values according to the change of the pressure of the hydraulic brake and by the application as a tool for the development of side airbag.

• 한국자동차공학회논문집
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• 제15권4호
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• pp.1-9
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• 2007

This study proposes a methodology to assess the traffic safety benefits of technical regulation for pedestrian leg. Traffic safety benefit is defined as the injury reduction in this study. Actual accident analysis and simulation experiments using LS-Dyna3d are conducted to establish statistical models for developing the methodology. The relationship between collision speed and parameters of the regulation is explored. An application example of the proposed methodology is also presented for more comprehensive understanding. It is believed that the proposed methodology would be greatly utilized in developing various technologies and policies to protect pedestrian.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 D
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• pp.2058-2060
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• 2002

The demand for safety and reliability of Nuclear Power Plants (NPPs) has been constantly increasing and economical operation is also an important issue. Developing and adopting predictive maintenance technology for the major systems or equipment is considered as one way to achieve these goals. This paper suggests the predictive maintenance methodology that can be applied to NPPs and describes a sample application of the Rod Control System (RCS) to verify the effectiveness of the methodology. It is expected that the same methodology can be adopted for other systems of NPPs and general industry fields when its effectiveness is verified.

• Carbon letters
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• 제6권2호
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• pp.96-100
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• 2005

Taguchi methodology has been applied to get an idea about the parameters related to the chemical vapour deposition technique, which influences the formation of semiconducting carbon thin film of a desired band gap. L9 orthogonal array was used for this purpose. The analysis based on Taguchi methodology suggests that amongst the parameters selected, the temperature of pyrolysis significantly controls the magnitude of band gap (46%). Sintering time has a small influence (30%) on the band gap formation and other factors have almost no influence on the band gap formation. Moreover this analysis suggests that lower temperature of pyrolysis (${\leq}$ $750^{\circ}C$) and lower time of sintering (${\leq}$ 1 h) should be preferred to get carbon thin film with the desired band gap of 1.2eV.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2002년도 춘계학술대회 논문집
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• pp.342-351
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• 2002

A personalized product recommendation is an enabling mechanism to overcome information overload occurred when shopping in an Internet marketplace. Collaborative filtering has been known to be one of the most successful recommendation methods, but its application to e-commerce has exposed well-known limitations such as sparsity and scalability, which would lead to poor recommendations. This paper suggests a personalized recommendation methodology by which we are able to get further effectiveness and quality of recommendations when applied to an Internet shopping mall. The suggested methodology is based on a variety of data mining techniques such as web usage mining, decision tree induction, association rule mining and the product taxonomy. For the evaluation of the methodology, we implement a recommender system using intelligent agent and data warehousing technologies.

• 동아시아경상학회지
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• 제3권2호
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• pp.21-25
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• 2015

Investment process on startup companies faces several difficulties based on the characteristics of this type of companies, such as lack of historical data, current operating losses and absence of comparable companies. In this paper we focus in a new methodology based on ordered weighted averaging (OWA) operators. OWA operators are useful instruments that enable the aggregation of information; in other words, from a data set we are able to obtain a single representative value of that set. The investment methodology presented consists on the application of OWA operators to the targeted startup companies based on the capacity of cash-flow generation and also on the planned scenario of future growth for each company. This paper shows that the methodology proposed can serve as a valuable tool, complementing the qualitative criteria (which, obviously, should not be ignored) for assessing and selecting a start-up investment.