• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.346-351
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• 2003

In this paper, an evaluation method of fracture toughness on interface cracks has been investigated under various mixed-mode conditions of the bonded scarf joints. Two types of the bonded scarf joints with an interface crack were prepared to analyze the stress intensity factors using boundary element method(BEM) and to perform the fracture toughness test. From the results of fracture toughness experiments and BEM analysis, an evaluation method of fracture toughness on interface cracks in the bonded components of dissimilar materials has been proposed and discussed.

• 한국항해항만학회지
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• 제38권3호
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• pp.203-209
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• 2014

As a sense of practical field, most researchers emphasize the importance of safety management to prevent marine accidents. The purpose of this paper is to develope a new safety evaluation method using Safety Index (SI) which is to measure the emotional feeling of navigation officer by traffic situations. In this study, the questionnaires with SI are used to investigate the degree of sensing levels of navigation officers according to the navigation situations. In addition, the traffic data obtained from AIS (Automatic Identification System) data are used to give actual situations in the questionnaire investigation. As results of questionaries investigations based upon the AIS data, it is shown that the Safety Index can be used as a criterion to determine the safety levels of ship navigating in a coastal areas.

• 한국안전학회지
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• 제25권6호
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• pp.186-196
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• 2010

It has been well known that traffic accidents occur under combined functional contributions of drivers, vehicles and road facilities, and that evaluation of safety levels for a specific road section or point is generally much complicated. Additionally, most of traffic accidents occur randomly implicating it is necessary to be evaluated in terms of probability theory. Thus, the evaluation model which reflects various characteristics and probabilistic distributions of traffic accidents has been necessary. The present paper provides a reliability based model with variables of probabilistic operating speeds and design speeds together which have been individually explaining associated characteristics in traffic accidents. Consequently, the model made it possible for speed management and road improvement projects to be evaluated in a common index. Application studies were performed in three cases. Through the studies, couples of facts were identified that the model successfully considered the probabilistic operating speeds and design speeds together and that then, the model evaluated road safety alternatives relatively which are complicatedly characterized and differently located.

• 대한전기학회논문지:전력기술부문A
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• 제55권11호
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• pp.453-462
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• 2006

This paper evaluates the reliability of KEPCO system using TRELSS, which is a probabilistic reliability evaluation program for large-scaled power system. In order to reflect the characteristic of KEPCO system, the sensitivity of reliability indices such as LOLP, EDLC, EENS and Energy Curtailment for variations of TRELSS parameter and input data was analyzed. Additionally, probabilistic reliability of KEPCO system reflecting sensitivity analysis results was systematically evaluated and simulated. Finally, maximum acceptable FOR of KEPCO system to satisfy reliability criterion, which meet in process of establishing the basic plan for long-term electricity supply and demand is suggested.

• 한국자동차공학회논문집
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• 제11권4호
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• pp.110-116
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• 2003

In this paper, an evaluation method of fracture toughness on interface cracks has been investigated under various mixed-mode conditions of the bonded scarf joints. Two types of the bonded scarf joints with an interface crack were prepared to analyze the stress intensity factors using boundary element method(BEM) and to perform the fracture toughness test. From the results of fracture toughness experiments and BEM analysis, an evaluation method of fracture toughness on interface cracks in the bonded dissimilar materials has been proposed and discussed.

• 한국음향학회:학술대회논문집
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• 한국음향학회 1994년도 FIFTH WESTERN PACIFIC REGIONAL ACOUSTICS CONFERENCE SEOUL KOREA
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• pp.686-691
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• 1994

For evaluating the response fluctuation of the actual environmental acoustic system excited by arbitrary random inputs, it is important to predict a whole probability distribution form closely connected with evaluation indexes Lx, Leq and so on. In this paper, a new type evaluation method is proposed by introducing three functional models matched to the prediction of the response probability distribution from a problem-oriented viewpoint. Because of the positive variable of the sound intensity, the response probability density function can be reasonably expressed theoretically by a statistical Laguerre expansion series form. The relationship between input and output is described by the regression relationship between the distribution parameters(containing expansion coefficients of this expression) and the stochastic input. These regression functions are expressed in terms of the orthogonal series expansion and their parameters are determined based on the least-squares error criterion and the measure of statistical independency.

• Computers and Concrete
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• 제13권5호
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• pp.633-648
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• 2014

The seismic safety of concrete dams is one of the important problems in the engineering due to the vast socio-economic disasters which may be caused by collapse of these infrastructures. The accuracy of the risk evaluation associated with these existing dams as well as the efficient design of future dams is highly dependent on a proper understanding of their behaviour due to earthquakes. This paper develops an anisotropic damage model for arch dam under strong earthquakes. The modified Drucker-Prager criterion is adopted as the failure criteria of the dynamic damage evolution of concrete. Some process fields and other necessary information for the safety evaluation are obtained. The numerical results show that the seismic behaviour of concrete dams can be satisfactorily predicted.

• 한국정보처리학회논문지
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• 제2권4호
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• pp.524-534
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• 1995

영상분할은 주어진 영상을 비슷한 성질을 지니는 영역들로 나누는 과정으로 컴퓨 터 비젼 분야에서 매우 오래 되었으면서도 어려운 문제이다. 지금 까지 많은 영상 분 할 방법들이 개발되었으며, 이러한 영상 분할 방법들을 평가하려는 연구가 계속되고 있으나 영상 분할의 특성상 많은 어려움이 있다. 본 연구에서는 영상 분할 방법을 자 동으로 평가하기 위하여 일반적으로 적용 가능한 평가 기준을 제시한다. 하나의 평가 기준이 가지는 약점을 보완하기 위하여 네 개의 평가기준, 즉 영역 경계선에 존재하 는 화소들의 차이 정도, 영역 경계선과 에지와의 일치 정도, 영역들 간의 유사 정도 및 영역들 간의 차이 정도를 통합한 평가 기준을 제시한다. 실험 결과를 통하여 제안 한 영상 분할 평가 방법이 매우 타당함을 알 수 있었다.

• 대한교통학회지
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• 제12권1호
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• pp.25-42
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• 1994

The traffic forecast is one of the most important analysis objects in the urban transportation planning process. The results of traffic forecast are the most widely used informations and give a critical influence on the major decision makings in the transportation planning process. Thus, they should be as much accurate and credible data, and evaluated to determine whether they are enough reliable to directly use in the planning process. However, the evaluation process is usually overlooked or abbreviated with a few exceptions according to the size and character of the project. Even though a planner or engineer tries to evaluate the assignment results, he/she is usually faced with certain difficulties since there are no established criteria and methods for the accuracy evaluation. Accordingly, the main purpose of this research placed on establishing the criteria and methods for the accuracy evaluation of the assignment results. The secondary purpose was to evaluate which assignment technique produces the most accurate assignment results by applying the established evaluation criteria and methods to an actual network. The research found that the proposed evaluation methods well operated in testing the accuracy of assignment results with few limits on application. Also, the incremental assignment was found to provide the best assignment results of existing assignment techniques (Stochastic, Iterative, Incremental, Equilibrium assignment) for the Seoul city network applied.

• 한국도서관정보학회지
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• 제32권4호
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• pp.45-75
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• 2001

이 연구의 목적은 신세기 대학도서관의 상보성 명제, 즉 인쇄자료와 디지털정보, 실물소장과 원격 접근, 인간중심의 참고봉사와 기술집약형 정보봉사, 자료집적소와 정보게이트웨이 등을 종합적으로 측정·평가할 수 있는 모형을 개발하는데 있다. 이를 위하여 일련의 선행연구를 이론적 배경으로 국내외의 관련단체가 제안한 평가시스템의 문제와 한계를 개관한 다음, 이해집단의 인식도를 조사·분석하여 종합적 평가모형(비중, 항목과 지표, 가중치, 척도 등)을 제안하였다 특히 대교협을 비롯한 관련단체의 평가모형이 디지털 인프라 및 봉사기능을 재단하는데 취약하고, 지표구성 및 척도기준의 논거가 부족하며, 실용성이 떨어진다는 비판에 주목하여 가중치의 배정모형을 다양하게 제시하였다.