• Journal of Power Electronics
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• 제9권1호
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• pp.61-67
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• 2009

In this paper, a simple technique is presented for robust stability testing of perturbed DC-DC converters having multi-linear uncertainty structure. This technique provides a necessary and sufficient condition for testing robust stability. It is based on the corollary of Routh criterion and gridding of parameters. The previous work based on parametric control theory using Kharitonov's theorem and Hermite Biehler theorem gives conservative results and only the sufficient condition of stability, whereas the proposed method provides the necessary and sufficient condition for testing robust stability and it is computationally efficient. The superiority of the method is compared with the Edge theorem.

• 한국생산제조학회지
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• 제6권3호
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• pp.36-43
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• 1997

In order to make unmanned machining systems with satisfactory performances, it is necessary to incorporate appropriate condition monitoring systems in the machining workstations to provide the required intelligence of the expert. This paper deals with condition monitoring for tool wear and breakage during turning operation. Developing economic sensing and identification methods for turning processes, sound pressure measurement and digital signal processing technique are proposed. The validity of the proposed system is confirmed through the large number of cutting tests.

• 대한기계학회논문집A
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• 제20권2호
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• pp.431-439
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• 1996

본 연구에서 탐구된 새로운 설계조건과 설계원칙들을 적용함으로써 세탁기용 트랜스미션으로 대표되는 기계 시스템을 효과적으로 설계할 수 있었다. 개발된 자동설계 프로그램을 이용함으로써 다양한 설계시뮬레이션을 단기간에 수행할 수 있었으며 설계 실무자로 하여금 설계변수와 상태변수 등에 관한 민감도를 파악하게 하는데 매우 효과적이었다. 본 연구에서 새롭게 제안된 시스템 설계조건들과 설계원치기들은 세탁기용 트랜스미션 뿐만 아닌 일반적인 기계시스템 설계시에도 적용될 수 있는 것으로 판단된다.

• 대한건축학회논문집:계획계
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• 제34권2호
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• pp.49-57
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• 2018

The purpose of this study is to analyze the current condition of green building education, which is a necessary condition to activate green architecture, with the need to reduce greenhouse gas emissions in the building sector. The main results are as follows. First, the level of education and the level of domestic green architecture were generally underestimated. Second, in order to increase the satisfaction of participants in green building education, it is necessary to increase the number of courses and to increase the number of lecturers who have excellent practical skills. Third, there is a need to strengthen green building programs related to BEMS and green remodeling. Fourth, it is necessary to expand the education on green architecture for the people in the architectural planning and design field and the related field officials. Fifth, green building education needs to be implemented in conjunction with curriculum of elementary, middle and high school. Sixth, it is necessary to diversify the PR(public relations) channels of the green building education program and to provide a way to give the employment increase point when the curriculum is completed. Seventh, there is a need to expand administrative and financial incentives for green architecture in order to revitalize green architecture education.

• 한국수학사학회지
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• 제22권1호
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• pp.75-88
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• 2009

본 연구는 수학적 지식의 발견과 정당화에서 분석의 역할을 논하고 학교수학에서 역할을 논의하고 있다.

• 대한수학회논문집
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• 제23권2호
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• pp.241-250
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• 2008

In this article, we find a counter example which shows that the well-known necessary condition about the boundary regularity of a stable strictly convex body is not a sufficient condition.

• Journal of the Korean Data and Information Science Society
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• 제17권1호
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• pp.205-211
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• 2006

For a linear regression model, the necessary and sufficient condition for the asymptotic consistency of the outlier test statistic is known. An analogous condition for the nonlinear regression model is considered in this paper.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 추계학술논문발표회 논문집
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• pp.490-494
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• 2008

We simulated a forest fire which was occurred in Yangyang area on 2005 and compared a results between two different weather conditions(real weather condition and mean weather condition since 1968) using FARSITE, which is a forest fire spread simulator for preventing and predicting fire in USDA. And, we researched a problem in the transition for introducing, so we serve the basic method for prevention and attacking fire. In the result, severe weather condition on 2005 effected a forest fire behavior. The rate of spread under real weather condition was about 4 times faster than mean weather condition. Damaged area was about 10 time than mean weather condition. Therefore, Climate change will make a more sever fire season. As we will encounter to need for accurate prediction in near future, it will be necessary to predict a forest fire linked with future wether and fuel condition.

• 대한수학회지
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• 제43권2호
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• pp.241-258
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• 2006

This paper gives conditions under which necessary optimality conditions in a locally Lipschitz program can be expressed as the invexity of the active constraint functions or the type I invexity of the objective function and the constraint functions on the feasible set of the program. The results are nonsmooth extensions of those of Hanson and Mond obtained earlier in differentiable case.

• 대한수학회지
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• 제46권5호
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• pp.1105-1117
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• 2009

In this paper a parameter identification problem for a damped sine-Gordon equation is studied from the theoretical and numerical perspectives. A spectral method is developed for the solution of the state and the adjoint equations. The Powell's minimization method is used for the numerical parameter identification. The necessary conditions for the optimization problem are shown to yield the bang-bang control law. Numerical results are discussed and the applicability of the necessary conditions is examined.