• Journal of the Korean Statistical Society
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• 제20권2호
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• pp.139-146
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• 1991

A generalization of an earlier diffusion model for system subject to continuous wear is presented. It is assumed that the state of the system is modelled by Brownian motion with negative drift and an absorbing barrier at the origin. A repairman arrives according to a stationary renewal process and increases the state of the system by a random amount if the state does not exceed a threshold. Various properties of this model are investigated including the distribution of the state of the system at time t, the first passage time to state 0 and the probability that the state of the system exceeds a certain level throughout a specified interval.

• 기술혁신연구
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• 제9권1호
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• pp.95-120
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• 2001

One of the systematic attempts for technological forecasting is Delphi Method that externalizes and manipulates unformalized experts opinion in a particular problem or subject. It has, however, a critical shortcoming that it can not reflect the degree of interaction that exists among forecast events or subject. Gordon and Hayward(1969) criticize that when the forecast events are strongly interrelated, a totally unrealistic consensus may result. They proposed a new forecasting method that considers the interaction of events, that is, Cross Impact Analysis (CIA). A number of related models have been developed after them. In this study, we examine a variety of research results related to CIA obtained by literature survey and propose the limitation and future research direction. This analysis would be expected to help us to create a strategic scenario on future technology development at the government and firm level.

• 공학교육연구
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• 제13권5호
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• pp.72-75
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• 2010

Design subjects have become popular in the engineering education. In these subjects, an active learning skill was introduced to students. Students have to decide a theme and the way how to study it and to find answers by themselves. This learning method was developed in the early year courses in the University of Tokushima. The common learning curriculum among whole university adopted this design subjects from 2005 of the school year and eleven more new subjects started. "Roots finding" is one of them and the objectives are to gain abilities of self-study through the research on a particular subject, and make report then presenting them. Self-learning ability, research ability and presentation skills were enhanced through this subject.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.361-363
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• 2011

This paper proposes a method for choosing the best transmission system expansion(TEP) plan considering an annual outage cost and a probabilistic transmission system reliability criterion ($_RLOLE_{TS}$). The objective method minimizes a total cost which are an investment budget for constructing new transmission lines and an annual outage cost, subject to the probabilistic transmission system reliability criterion, which consider the uncertainties of power system facilities. Test results on an existing 21-bus system are included in the paper. It demonstrated the suitability of the proposed method for solving the transmission system expansion planning problem subject to practical future uncertainties.

• 한국경영과학회지
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• 제33권2호
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• pp.1-16
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• 2008

The purpose of this paper is to propose a new binary classification method for predicting corporate failure based on genetic algorithm, and to validate its prediction power through empirical analysis. Establishing virtual companies representing bankrupt companies and non-bankrupt ones respectively, the proposed method measures the similarity between the virtual companies and the subject for prediction, and classifies the subject into either bankrupt or non-bankrupt one. The values of the classification variables of the virtual companies and the weights of the variables are determined by the proper model to maximize the hit ratio of training data set using genetic algorithm. In order to test the validity of the proposed method, we compare its prediction accuracy with ones of other existing methods such as multi-discriminant analysis, logistic regression, decision tree, and artificial neural network, and it is shown that the binary classification method we propose in this paper can serve as a premising alternative to the existing methods for bankruptcy prediction.

• 한국실내디자인학회논문집
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• 제38호
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• pp.48-56
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• 2003

This study is purposed to find the transition of the perspective connected with visual modality. The perspective based on Greek optics and euclidean geometry and rediscovered in Renaissance represents the object according to the particular moment and the point of view, is a principal fact which affect architecture, the form of a city and the spatial organization and symbolizes an ideal of the times. It embodied perception which treats the space rationally on the basis of realism and became visual modality based on the separation of the seeing subject and the world of the object. The point of view became one with the vanishing point which made up the shape and after Renaissance for four hundred years a straight line, a right angle and a circle got to be favorite geometrical choices in architecture. A fixed point of view of the subject is getting to change and break up fundamentally by the new visual technologies of the modem times.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.557-559
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• 2005

This paper proposes a method for choosing the best composite power system expansion plan considering a contingency security criterion. The proposed method minimizes the investment budget fer constructing new transmission lines subject to contingency criterion. it models the power system expansion problem as an integer programming one. The method solves for the optimal strategy using a branch and bound method that utilizes a network flow approach and the maximum flow-minimum cut set theorem. Although the proposed method is applied to a simple sample study, the test results demonstrate that the proposed method is suitable for solving the power system expansion-planning problem subject to practical future uncertainties.

• 영어어문교육
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• 제5호
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• pp.79-101
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• 1999

With the advent of the 6th and the 7th national educational curricula in Korea. English language teaching in communicative perspective has been highly recommended and widely practised in that context. The aim of new approach is to enhance the students' general communication abilities in English. However, English teachers still find it very hard to improve the students' communicative competence in English since English remains to be taught as a school subject. In so far as English is taught as a school subject, students' attention is paid to the formal elements of English and the increase in communicative competence in English is hardly expected Only when the students' attention is paid to the content, their communicative competence is expected to increase. The best way to shift the students' attention from formal elements to content is to teach other school subjects in English, that is, English immersion education. To introduce immersion education to Korea, the two most successful examples of Singapore and Hong Kong are reviewed in terms of language policies and general practices in their primary and secondary schools respectively. To implement the program into Korea, extensive research on it is expected henceforth.

• 한국컴퓨터정보학회논문지
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• 제21권10호
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• pp.183-190
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• 2016

In this paper, we have looked at through core competences and contents of Informatics curriculum in middle school by expert questionnaire and Focus Group Interview(FGI). Among nine core competences of Informatics subject in curriculum, abstraction and automation were easily found, but creative harmony and cooperation were indirectly confirmed in the statements of teaching and assessment sections of Informatics curriculum in middle school. It was also identified that some core competency elements are redundant or hardly to found in the contents of Informatics curriculum. In addition, various opinions about Informatics curriculum have been put forward over the FGI. The results of this study will be the case that can be consulted on new revised Informatics curriculum to be developed further.

• 대한기계학회논문집A
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• 제23권11호
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• pp.2058-2066
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• 1999

The present paper proposes a new dynamic analysis method for multi-span Timoshenko beam structures supported by joints with damping subject to moving loads. An exact dynamic element matrix method is adopted to model Timoshenko beam structures. A generalized modal analysis method is applied to derive response formulae for beam structures subject to moving loads. The proposed method offers an exact and closed form solution. Two numerical examples are provided for validating and illustrating the proposed method. In the first numerical example, a single span beam with multiple moving loads is considered. A dynamic analysis on a multi-span beam under a moving load is considered as the second example, in which the flexibility and damping of supporting joints are taken into account. The numerical study proves that the proposed method is useful for the vibration analysis of multi-span beam-hype structures by moving loads.