• 한국멀티미디어학회논문지
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• 제18권3호
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• pp.387-400
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• 2015

A fuzzy logic based mobile robot navigation system was developed to improve the driving ability without trapping inside obstacles in complex terrains, which is one of the most concerns in robot navigation in unknown terrains. The navigation system utilizes the data from ultrasonic sensors to recognize the distances from obstacles and the position information from a GPS sensor. The fuzzy navigation system has two groups of behavior rules, and the robot chooses one of them based on the information from sensors while navigating for the targets. In plain terrains the robot with the proposed algorithm uses one rule group consisting of behavior rules for avoiding obstacle, target steering, and following edge of obstacle. Once trap is detected the robot uses the other rule group consisting of behavior rules strengthened for following edge of obstacle. The output signals from navigation system control the speed of two wheels of the robot through the fuzzy logic data process. The test was conducted in the Matlab based mobile robot simulator developed in this study, and the results show that escaping ability from obstacle is improved.

• Nuclear Engineering and Technology
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• 제33권1호
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• pp.12-24
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• 2001

The post-LOCA long term cooling (LTC) performance of the Korean Standard Nuclear Power Plant (KSNPP) is analyzed for both small break loss-of-coolant accidents (LOCA) and large break LOCA at cold leg. The RELAP5/MOD3.2.2 beta code is used to calculate the LTC sequences based on the LTC plan of the Korean Standard Nuclear Power Plants (KSNPP). A standard input model is developed such that LOCA and the followed LTC sequence can be calculated in a single run for both small break LOCA and large break LOCA. A spectrum of small break LOCA ranging from \ulcorner.02 to 0.5 k2 of break area and a double-ended guillotine break are analyzed. Through the code calculations, the thermal-hydraulic behavior and the boron behavior are evaluated and the effect of the important action including the safety injection tank (SIT isolation and the simultaneous injection in LTC procedure is investigated. As a result, it is found that the sufficient margin is available in avoiding the boron precipitation in the core. It is also found that a further specific condition for the SIT isolation action need to be setup and it is recommended that the early initiation of the simultaneous injection be taken for larger break LTC sequences.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2008년도 춘계 종합학술대회 논문집
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• pp.10-14
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• 2008

컴퓨터 애니메이션을 이용한 군중 장면은 영화나 게임에서 자주 등장한다. 군중의 보행동작을 생성하기 위해 기존의 기술들은 주로 군중의 각 개체들의 행동을 모델링하여 접근하였다. 하지만, 군중의 규모가 커질수록 모든 개체를 개별적으로 제어하기는 어려워진다. 따라서 대규모 군중의 경우 개체별로 행동을 모델링하기보다 집단별로 모델링하여 보다 직관적으로 군중을 제어할 수 있다. 본 논문에서는 집단의 경로 추적 행동을 시뮬레이션하기 위한 집단 역장 모델을 제안한다. 집단은 같은 목적, 즉 같은 경로를 따라 무리지어 행동하는 개체들의 모임으로 정의된다. 또한 집단의 무리짓는 행동은 정렬, 응집, 분리의 세 가지 특징으로 규정지을 수 있다. 집단 역장 모델을 통해 이러한 집단의 특징들을 보존하면서 개체 간의 충돌을 자연스럽게 회피할 수 있다. 제안한 기술을 통하여, 사용자는 나란히 늘어선 집단에서 동그랗게 뭉쳐진 집단까지 원하는 형태의 경로 추적 애니메이션을 생성할 수 있다.

• 대한토목학회논문집
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• 제35권2호
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• pp.427-436
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• 2015

본 논문은 무신호 교차로에서 보행자의 횡단행태에 영향을 주는 요소를 분석하였다. 보행행태는 교차로 주변의 환경과 횡단의 기준, 안전에 대한 예견, 순간적인 판단 등이 복합적으로 작용하는 정신적 스트레스의 결과이다. 이러한 복합적 스트레스는 개인의 속성, 교통여건, 환경요인 등 다양한 요인에 의해 영향을 받는데, 이러한 영향요인을 파악하여 교차로를 운영하는데 있어 보행친화적인 환경을 조성할 필요가 있다. 현장과 설문 조사를 통하여 보행자가 비신호 교차로를 횡단하는데 있어서 영향을 주는 다양한 결정변수를 기초로 하여 횡단시도 횟수, 기다림 시간 및 보행횡단 만족도 등에 대한 횡단행태를 분석하는 것이 목적이다. 횡단시도횟수에 대한 각 요소별 특성을 분석하기 위해 $x^2$테스트를 실시하였으며 횡단을 위한 기다림 시간에 영향을 주는 요소를 분석하기 위해 위험률 모형을 구축하였다. 마지막으로 구조방정식을 적용하여 보행자의 보행 횡단 환경에 대한 만족도에 대한 직 간접 효과도 제시되었다.

• 패션비즈니스
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• 제8권5호
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• pp.41-59
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• 2004

The purpose of this study is to analyze consumers' purchase behavior for the counterfeits of fashion luxury brands. The research method of the study used a naturalistic approach. The first participant observation was carried out in the internet sites in order to collect the data on the purchase behavior for counterfeits; and the second participant observation was applied in the Dongdaemun shopping mall, Namdaemun shopping mall and Itaewon shopping mall; finally 6 informants were selected and then an interview was held with them. The results of the study are as follows; 1. The reasons for the first purchase of counterfeits are variously shown according to life stages, and the repetitive purchase behavior is influenced by the degree of satisfaction for the first purchase. The information collection for counterfeits is widely made through various media, and especially the information collection is active and positive in the case of planned purchase but it is passive and negative in the case of unplanned purchase. 2. The most important criteria in purchasing counterfeits is the degree of similarity with luxury brands and other criteria include price, design, utility etc. The majority of purchase items is not clothing but miscellaneous goods which are more similar in terms of design and quality. The purchase of counterfeits is made by impulse purchase but the purchase of luxury brands is made by planned purchase. 3. The rationalization mechanism for the purchase of counterfeits is observed in all informants, which is a sort of defence mechanism for avoiding a guilty conscience to buy illegal goods.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2011년도 추계학술대회
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• pp.16-18
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• 2011

This study aims to identify the degree of safety when mariners take their actions in several different situations. We have carried out many experiments in order to observe mariners' behavior, and then measured the safety level that is based on their actions to avoid dangerous collision situations. One of the most important actions that mariners have to take, either as their daily routine or when they are in a collision situation and then want to avoid that situation is the lookout. In this paper, behaviors on the lookout have been defined as a standard sequence of three steps that are "time of first detection", "time of recognition as risky vessel" and "time of starting avoiding action", and the suitability and applicability of the definition have been shown. And also we propose the risk assessment on the collision and the recommendation for reducing the collision at sea. Some analyzing results and the application of the results are reported. The sequence of lookout is also understood. By combining these knowledge and some systematic studies, we propose the risk assessment on the collision and the recommendation for reducing the collision at sea.

• 한국게임학회 논문지
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• 제19권6호
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• pp.5-14
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• 2019

본 논문에서는 게임 환경에서 Agent Based 와 Cellular Automata 모델 시스템을 이용한 보행자들의 집단행동 움직임에 대한 모델링과 그 시뮬레이션을 제안한다. 군중들의 사회적 행동은 복잡하고 중요하며, 이를 근거로 게임 환경에서 AB와 CA모델 시스템을 바탕으로 어떤 목적을 가진 군중 상호작용을 나타나는 모습을 게임 프로토타입 모델로 구현하였다. 본 실험은 실제 보행자들이 있는 위험상황에서 군중행동을 연구하기 위하여 효율적이고 정확한 플랫폼으로서 집단 움직임의 가능성을 보여주었다.

• Computers and Concrete
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• 제13권4호
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• pp.547-567
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• 2014

Precast Seismic Structural Systems (PRESSS) provided an iterative procedure for obtaining optimum design of unbonded post-tensioned coupled precast concrete wall systems. Although PRESSS procedure is effective, however, it is lengthy and laborious. The purpose of this research is to employ Artificial Neural Network (ANN) to predict the optimum design parameters for such wall systems while avoiding the demanding iterative process. The developed ANN model is very accurate in predicting the nondimensional optimum design parameters related to post-tensioning reinforcement area, yield force of shear connectors and ratio of moment resisted by shear connectors to the design moment. The Mean Absolute Percent Error (MAPE) for the test data for these design parameters is around %1 and the correlation coefficient is almost equal to 1.0. The developed ANN model is then used to study the effect of different design parameters on wall behavior. It is observed that the design moment and the concrete strength have the most influence on the wall behavior as compared to other parameters. Several design examples were presented to demonstrate the accuracy and effectiveness of the ANN model.

• 디자인학연구
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• 제15권3호
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• pp.241-248
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• 2002

한글기계화에 대한 논쟁의 초점은 어디까지나 벌식에만 맞추어져 왔다. 현재 표준안으로 되어있는 2벌식 키보드에서 실제 한글을 사용할 때의 문제점은 윗글쇠의 빈번한 사용에 따른 오타의 증가와 피로도의 누적이었다. 윗글쇠 사용상의 문제점을 해결하기 위해서는 다음과 같은 가설을 세울 수 있다. '윗글쇠의 위치와 디자인을 변경함으로써 윗글쇠를 누를 때 다른 키(key)와의 간섭을 제거하여 한글 입력시의 오타율을 줄일 수 있다.' 본 연구에서는 윗글쇠의 위치와 디자인을 변경한 프로토타입(Prototype)을 제작하고, 사용행태 실험을 통해 그 효과를 검증하고자 하였다. 실험 결과에 의하면 윗글쇠의 위치 변경은 오히려 숙련자들에게 혼란을 일으킬 수 있으나, 윗글쇠 위치를 유지하면서 하단에 있는 다른 키들을 다른 곳으로 이동시키고 윗글쇠의 크기와 디자인을 개선함으로써 윗글쇠와 다른 키간의 간섭을 줄여 위치 인식을 확실하게 하고 오타를 줄일 수 있는 것으로 나타났다. 또한, 오타는 감소하는 반면 연타속도에는 영향을 미치지 않음으로 인해 한글 입력시의 효율을 향상시킬 수 있음을 알 수 있었다. 본 연구에서는 윗글쇠의 위치 변경과 디자인 개선 전후의 행동특성 관찰을 위주로 실험하였으나, 향후에는 종합적인 한글자판의 개선을 위해, 현재 윗글쇠 하단에 있는 다른 기능 키들의 적절한 위치 선정을 통해 전체적인 개선 효과를 얻을 수 있는 연구가 이루어져야 할 것이다.

• Journal of Community Nutrition
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• 제3권2호
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• pp.69-76
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• 2001

This study was conducted to provide current information on dietary behaviors and dish preferences of elementary school children and to suggest guidelines for proper dietary behaviors. To accomplish study objectives survey was executed using the questionnaire for 420 fifth and sixth grade school children, chosen from schools in Kangwha-gun and East River District of Seoul. A questionnaire largely consists of categories including general characteristics, dietary behavior and preferences of the subjects for some dishes. Results showed 30％ of the subjects had breakfast irregularly. A majority of the subjects took Korean style dishes of cooked rice and soup for breakfast. fifty-eight percent of subjects had a regular meal time. Imbalanced diet(avoiding specific flood group thereby causing unbalance in nutrient intake) habit group was estimated to be 47.3%. Twenty one percent had a habit of overeating. In choosing the snack, taste was considered to be a more important factor than nutrition. Advertisement of the snack was shown to be one of the Important factors in selecting the snack. The girls were more concerned about weight control than the boys. Also the girls were likely to rely on the diet to control weight since they exercised only in the physical c1ass while the boys exercised regularly. Generally, children liked animal protein containing foods and the preference for vegetables was low. In order to improve overall dietary behavior, systematic nutrition education programs reflecting sex difference should be developed. Dish preference data would be very useful in selecting substitutive dish for the s[hoof lunch menu to improve imbalanced diet. (J Community Nutrition3(2) : 69∼76, 2001)