• 방송공학회논문지
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• 제21권2호
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• pp.268-271
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• 2016

배경 모델과 배경 차분화로 구성되어 있는 전경객체 추출은 다양한 컴퓨터 비젼 응용에서 중요한 기능이다. 조명 변화를 고려하지 않은 기존 방법들은 급격한 조명 변화에서는 성능이 저하된다. 본 레터에서는 이 문제를 해결할 수 있는 조명 변화에 강인한 배경 모델링 방법을 제안한다. 제안 방법은 다른 적응률을 가진 두 개의 배경 모델을 사용함으로써 조명 조건에 신속하게 적응할 수 있다. 본 논문의 제안 방법은 non-parametric 기법으로서 실험에서는 기존 non-parametric 기법들보다 우수한 성능 및 낮은 복잡도를 보여줌을 증명하였다.

• 한국항공우주학회지
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• 제43권8호
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• pp.684-691
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• 2015

덕티드 로켓 가스발생기용 추진제 성능을 검증하기 위한 실험에서 직경이 10mm인 파이프와 최소 직경이 8.7mm인 수축 노즐을 배출 튜브로 사용하였을 때 급격한 압력 증가가 관찰되었다. 급격한 연소 압력 증가는 배출 튜브를 통과하는 유동의 열 질식(thermal choking) 때문인 것으로 판단하였다. 본 연구에서는 원형 파이프를 사용하는 경우, 배출 튜브 유동의 열 질식을 고려하여 가스발생기 연소 압력 변화를 예측하였다. 그 결과, 배출가스의 비-평형 화학반응으로 인한 배출 튜브 유동의 열 질식 발생이 급격한 연소 압력 증가의 원인임을 확인하였다. 특히 덕티드 로켓의 높은 압력 지수는 배출 튜브 내에서 발생하는 열에 매우 민감하게 반응하여 배출 튜브 내의 열 질식 가능성을 높이는 것으로 분석되었다. 또한 배출 튜브로 단면적의 변화가 있는 발산형 파이프를 사용하면 가스발생기의 급격한 연소 압력 증가를 예방할 수 있을 것으로 판단하였다.

• 산업경영시스템학회지
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• 제24권65호
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• pp.51-63
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• 2001

The present experiment investigated the possibility of evaluating of the human sensibility contingent on the speed and modes of driving using the responses from the autonomic nervous system, subjective assessments, Simulator Sickness (55) in dynamic simulator. The three conditions of the speed of driving were 40 $\pm$ 10 km/h, 100$\pm$10 km/h, 160 $\pm$ 10 km/h, and the participant was instructed to drive the car for three minutes on the elliptical track. It is programed in such a way that the modes of driving can be changed smoothly using road DB in Dynamic Simulator, and for signifying the change of the condition the road signs were used. The instruction was given to the participant to drive the car on the fixed speed of 20 km/h for 30 seconds, then to drive the car on sudden-start mode of driving from the 20 km/h to 160 km/h within 10 seconds. For the sudden-stop mode of driving, it was instructed that stop the car from the speed of 160km/h to 20km/h within 10 seconds when the subject see the road sign, then drive the car at the fixed speed of 20 km/h for 30 seconds. The results of the subjcetive assessment showed that the level of pleasantness and the tension was increased, and physiological response showed that the level of activity of the autonomic responses were also increased as the speed of the car increased. Also, for results on the driving modes showed that the level of pleasantness was highest for the sudden-stop, next highest was sudden-start, and the lowest was 20 km/h fixed speed condition for the subjective assessment, and tile order of the level of activation of the autonomic nervous system showed the same results as above. From the results of the present study it was concluded that the presentation and evaluation of the stimulus for the human sensitivity is possible in dynamic simulator.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 추계학술대회
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• pp.221-223
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• 2016

현재 자동차 시장에서는 IT와 자동차가 결합되며 여러 가지 편리한 기능을 사용할 수 있는 모델들이 출시되고 있다. 이러한 변화는 운전에 관련하여 편리하고 유용한 기능을 많이 쓸 수 있다는 장점이 있는 반면 이러한 전자장비들의 오작동으로 인해 간간히 발생하는 차량의 결함은 심각한 사고를 유발할 수 있다. 그중 가장 심각하다고 판단되는 자동차 급발진 사고는 운전자의 목숨까지도 위협하는 심각한 결함이다. 하지만 급발진사고는 사고의 원인조차 정확하게 규명되지 않았으며 대비가 충분히 이루어지지 않아 제조사 측에서는 운전자 부주의라는 답변으로 책임을 회피하고 있으며 그에 따라 운전자의 부담은 계속해서 증가하고 있다. 따라서 본 논문에서는 통합 모듈을 통해 운전석 내부의 영상과 자동차의 엑셀과 브레이크 등 제어부분의 상태를 데이터화 시켜 급발진 사고를 대비하기 위한 시스템을 설계 하였다.

• 한국환경교육학회지:환경교육
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• 제22권1호
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• pp.68-82
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• 2009

Global climate change is associated with all of the human activity, and its sudden change can be taken an issue of the serious environmental problem in our human society. The purpose of this study is to develope the goal and the content system for the climate change education. As a result, first, according to the questionnaires on climate change, students from Grade 3 to Grade 10 seem to interpret it as fragmentary perspectives. In addition, in terms of students' own actions as the corresponding strategy to climate change, the higher their grades were, the lower their actions were. Second, the development goal on climate change and its educational directions were set by reflecting students' perception. The education goal on climate change is to perceive the changing environment by understanding phenomena of climate change, to propose plans that can mitigate and adjust climate change through a variety of research, and to keep practicing the proposed plans as a member of a community for the global environment. Third, fields and items of educational contents to climate change were created and drawn out. The content system is composed of 'basic science of climate change', 'relationship with climate change', and 'coping with climate change'. Furthermore, concrete contents for the climate change education in elementary school were suggested so that its goal and content system can be used in the existing curriculum.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1045_1046
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• 2009

This paper presents an active and reactive power compensator for the wind power system with squirrel-cage induction generator. The developed system is able to continuously compensate the active and reactive power. The 3-phase inverter operates for the compensation of reactive power, while the DC/DC converter with super-capacitors operates for the compensation of active power. The proposed compensator can be expected that developed system may be used to compensated the abrupt power variation due to sudden change of wind speed or sudden power-drop by tower effect. It can be also applied for the distributed generation and the Micro-Grid.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.239-243
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• 2012

This paper is concerned with turbulent flow computations using Large Eddy Simulation (LES) and the flow interaction of vortex shedding in a cylindrical duct flow driven by mass blowing through the wall. The purpose is to analyze non-linear combustion characteristics in the presence of vortex shedding generated in a hybrid rocket motor. Experimental studies have shown sudden changes in pressure (referred as a DC-shift), which depend on the strength of vortex strength of incoming flow. The combustion instability because of a sudden change in pressure fluctuations is mainly related with the interaction between vortex shedding. Therefore LES computation on a duct with injected normal blowing was performed to simulate the turbulent flow interactions with the behaviors of vortices and vortex structures along the injected wall.

• 생명과학회지
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• 제20권5호
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• pp.639-643
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• 2010

비육우의 공장, 회장 및 결장의 특징적 괴사 출혈성 장염 증상은 폐사 증후군과 관련이 있는 것으로 인식되고 있다. 특히 젖먹이 송아지들이 폐사 증후군에 가장 영향을 받는데, 포유시 송아지에게 과식을 시키거나, 비위생적 초유 급유, 체온 하강 및 스트레스는 장독혈증 발생의 원인들이다. 2006년 7월 중 경북 영천 지역에서 축우의 폐사가 발생하였다. 식욕부진, 의기소침, 간헐적인 설사 및 경미한 호흡 곤란을 제외하고는 특별한 임상 증상은 없었으나, 조직학적 소견에 의하면, 심장, 신장, 간, 비장 및 임파선을 포함한 각종 기관에서 globular leukocytes 의 침윤뿐 아니라 핵내 봉입체가 현저하게 나타났다. 비장과 림프조직에서는 림프 괴사와 림프구 괴사로 인한 'starry sky appearance'를 나타내었다. 소장 점막 하에서는 다량의 globular leukocytes와 호산 구의 침윤과 함께 호 염기성 세포 집단이 관찰되었다. 봉입체가 있는 소장 조직의 단면은 그램 염색에 대해 조직 화학적으로 양성 반응을 나타내었다. 결론적으로, 비축우의 폐사 원인은 조직학적 및 조직화학적 분석 결과를 근거로 Clostridium perfringens D 형균에 의한 장독혈증으로 진단되었다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2008년도 추계학술대회 논문집
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• pp.48-50
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• 2008

A wind power system with squirrel-cage induction generator has irregular change of output power according to the sudden change of wind speed. This paper describes the development of a active and reactive power compensator, which is composed of a 3-phase inverter and a bidirectional DC/DC converter with super-capacitor. The operational characteristic was analyzed through simulations with PSCAD/EMTDC and experimental works with a scaled model. The developed system can continuously compensate the active power change with energy storage and the reactive power change with 3-phase inverter.

• 한국실내디자인학회논문집
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• 제27권3호
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• pp.136-144
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• 2018

The purpose of this study is to examined the unconscious response of the pupil in the observation toward the image in the eye-tracking experiments that target on a large complex cultural space. Twenty-five men participated in this experiment and the observation data were analyzed in seconds per minute on watching time. It could examine the unconscious response of information searching in the change of pupil size in the process of observing the space. The results could be defined as following several points. First, it was possible to outline the unconscious response characteristics of pupil by analyzing sudden changes in pupil size as total, cumulative, and individual. The response characteristics using frequency and time can be utilized as the analytical method to examine the degree of interest of spatial components according to the purpose of analysis in the future. Second, according to the over ${\pm}5%$ of cumulative variation rate on the pupil size change, during in the 60 seconds, the continuous pupil dilation was used 25.2 seconds in 8.8 rounds and the pupil reduction was used 18.0 seconds in 7.0 rounds. Third, when the variation rate of ${\pm}5%$ or more was regarded as the sudden changes on pupil size by individual variation, the pupil dilation was 7.2 rounds of 8.6 seconds and pupil reduction was 6.0 seconds in 5.0 rounds. This means that the pupil increases 9.3% in one expansion and decreases -8.5% in the reduction process. As regarding pupil changes as cumulative rate, it appeared high change rate on pupil reduction but it became higher on pupil dilation in individual.