• 한국해양공학회지
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• 제23권6호
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• pp.23-31
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• 2009

The interaction of incident monochromatic waves with a bottom-mounted vertical porous circular cylinder is investigated using the framework of the three-dimensional linear potential theory. The porosity of the circular cylinder is uniform vertically but varies in the circumferential direction. By adjusting the porosities of the circular cylinder, both the wave blocking performance of a porous semi-circular breakwater and the wave responses inside a circular harbor with an entrance are applied as calculation examples. It is found that the reflected waves, wave run-up, and wave forces are significantly reduced due to wall porosity, which are positive factors for a breakwater, and the amplification factor of a circular harbor at resonant frequencies is greatly reduced by a porous sidewall.

• 한국해양공학회지
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• 제30권3호
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• pp.151-160
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• 2016

The diffraction and radiation of linear waves by an array of truncated floating multiple buoys are solved using the interaction theory based on a matched eigenfunction expansion method (MEEM). The interaction processes between multiple buoys are very complex and numerous, because the scattered and radiated waves from each buoy affect the others in the array. Our primary aim is therefore to construct the rigorous wave exciting forces and hydrodynamic forces to deal with the problem of multiple interactions. This present method is applied to a square array of four buoys with two incidence angles, and the results are given for the wave excitation forces on each buoy, heave RAO for each buoy heaving independently, and wave elevations around the buoys and wave run-up. The analytical solutions are in good agreement with the numerical solutions obtained from commercial code (WAMIT).

• 지식경영연구
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• 제9권4호
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• pp.35-49
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• 2008

The purpose of the study is to develop and validate an instructional design model from the perspective of the knowledge creation. To serve the purpose, the researcher conducted 1) literature review to find causal relationship model among knowledge creation factors and to propose a hypothetical instructional design model, 2) data analysis with 50 senior level e-Learning instructional designers, and 3) testing the fitness of the proposed model and relevant causal-relational hypotheses. Results indicate; 1) the proposed model fit to the empirical evidence, 2) 6 hypotheses among 11 were validated. A typical instructional designer's personal competency was evidenced as the most powerful independent variable that predicted knowledge acquisition, knowledge sharing, and the application of the instructional models. However, the expected effect of instructional design models toward other dependent variable was not be found. In addition, further suggestions for the future research are addressed.

• 한국산업안전학회:학술대회논문집
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• 한국안전학회 1997년도 춘계 학술논문발표회
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• pp.67-75
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• 1997

To establish testing method for ignition energy of explosive powders caused by electrostatic discharge, one testing method using a very small quantity of tested powders ( Frima ) was proposed, and the influence of discharge - limiting resistance connected in series into a capacitive discharge circuit on ignition energies of explosive powders was investigated using, as tested powders. As a result the minimum ignition energy was 9 mJ when discharge-limiting resistance was 300 k$\Omega$. The reason for the dependence of ignition energy on discharge-limiting resistance was thought to the difference in the type of electrostatic discharge, such as arc or glow discharge, from the observation of discharging wave forms.

• 한국해안해양공학회지
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• 제5권4호
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• pp.350-356
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• 1993

본 연구에서는 천수역 비선형 방정식인 Boussinesq 방정식을 방파제에 의한 산란문제에 적용하였다. 방파제에 의한 파랑변형을 수치계산하기 위하여 경계치문제는 유한요소법을 사용하였고 시간에 따른 진행은 Runge-Kutta 방법을 사용하였다. 수치모델로 2차원 수로에 입사파의 진행방향과 수직으로 방파제가 놓여있는 경우를 생각하였으며 방파제의 길이와 두께변화에 따른 파랑변형에 미치는 영향을 살펴보았다. 또한 후류 경계면이 막혀있는 경우와 열려있는 경우를 고려하였으며 선형결과와 비선형결과의 차이를 살펴보았다.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2008년도 한국우주과학회보 제17권1호
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• pp.28.2-28.2
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• 2008

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2008년도 한국컴퓨터종합학술대회논문집 Vol.35 No.1 (B)
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• pp.146-149
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• 2008

유비쿼터스 컴퓨팅 시대가 도래함에 따라 크고 작은 수많은 컴퓨팅 장치들이 집, 사무실, 자동차 등 도처에서 지원되고 있으며, 손목시계형, 목걸이형 등 소형 액세서리 웨어러블 컴퓨터도 다수 출현하여 사용자에게 보다 편리하게 정보를 제공하고자 하는 연구들이 진행되고 있다. 웨어러블 컴퓨팅 장치는 사용자를 위해 정보를 제공하는 입력 장치로도 사용되고 있으나, 정보를 표현하고 제공하는 좋은 출력 장치이기도 하다. 본 논문에서는 다수의 입출력 장치들과 연동하여 다중 피드백을 효과적으로 지원할 수 있는 피드백 인터페이스 프레임워크를 제안하고, 손목밴드형 시스템에서 구현한 결과에 대해 논의한다.

• 대한한방종양학회지
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• 제3권1호
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• pp.207-219
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• 1997

We experienced a case of postobstructive pneumonia in lung cancer patient by orinetal medical treatment(Herbal medication, Acupuncture therapy, Moxa therapy, Aqua-acupuncture therapy, Carbon radiotherapy), and through it we got a good result to report. According to the above results, it could be suggested that Jukyeopseokgo-tanggagambang extract has indirect autitumor effects by strengthening the effects of MMC on tumor cells.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2015년도 춘계 종합학술대회 논문집
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• pp.271-272
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• 2015

정부의 ICT R&D는 전체산업 관점과 거시적 목적 지향적인 R&D 추진체계에서 필요한 R&D 목적달성을 위해 R&D투자재원의 효율적 배분이 매우 중요한 기능이 된다. 즉, R&D재원배분에 대한 다양한 기준들이 존재할 수 있으며, 이러한 상충적 배분기준들 사이에 객관적이고 효율적인 재원투자의 우선순위와 가중치가 기본적으로 필요하게 된다. R&D계획수립과 지원 분야선정을 위한 방법론으로 보편적으로 사용되고, 현장적용에 객관성을 확보하고 있는 AHP(Analytic Hierarchy Process) 모형을 통해 상충적 다중의사결정에 발생하는 기준의 선호에 대한 쌍대비교를 통해 객관적 선택기준과 대안적 선택에 대한 의사결정 프레임워크를 제공해준다. 따라서 본 연구에서는 정부의 ICT산업경쟁력 제고 목적달성을 위한 투자부문과 기술분야에 대한 실증적인 의사결정구조와 재원배분안을 제시하고자 한다.

• 대한전기학회논문지
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• 제39권8호
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• pp.828-835
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• 1990

A new state feedback control scheme is proposed to improve the stability and dynamic performances of the series resonant converter (SRC). The proposed scheme can be easily implemented without speed limitation. Design parameter of the proposed control is the ratio of the state feedback gains. A closed loop dynamic modeling for the SRC with the proposed control law is derived. Parametric curves which can be used to select the design parameter in the control system are presented. The experimental results show that the excellent dynamic performance of the converter can be obtained by properly selecting the design parameter. The results are further compared with both the theoretical analysis and the frequency control.