• Ocean and Polar Research
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• 제42권3호
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• pp.179-194
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• 2020

The present study aims to evaluate the effects of satellite-based SST (OSTIA) assimilation on a regional ocean circulation model for the Yellow and East China Seas (YECS), using three different assimilation methods: the Ensemble Optimal Interpolation (EnOI), Ensemble Kalman Filter (EnKF), and 4-Dimensional Variational (4DVAR) techniques, which are widely used in the ocean modeling communities. The model experiments show that an improved initial condition by assimilating the SST affects the seasonal water temperature and water mass distributions of the YECS. In particular, the SST data assimilation influences the temperature structures horizontally and vertically in winter, thereby improving the behavior of the YS warm current water. This is due to the fact that during wintertime the water column is well mixed, which is directly updated by the SST assimilation. The model comparisons indicate that the SST assimilation can improve the model performance in resolving the subsurface structures in wintertime, but has a relatively small impact in summertime due to the strong stratification. The differences among the different assimilation experiments are obvious when the SST was sharply changed due to a typhoon passage. Overall, the EnKF and 4DVAR show better agreement with the observations than the EnOI. The relatively low performance of EnOI under storm conditions may be related with a limitation of EnOI method whereby an analysis is obtained from a number of climatological fields, and thus the typhoon-induced SST changes in short-time scales may not be adequately reflected in the data assimilation.

• 대한의용생체공학회:의공학회지
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• 제22권5호
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• pp.393-402
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• 2001

전체 심혈관계의 혈류역학적 특성을 분석할 수 있는 수치해석 방법을 개발하였다. 이는 12개의 요소들로 구성된 lumped parameter모델에 기초하고 있으며 인체의 신경계에 의한 자율조절기능을 모사하기 위해 주로 혈압의 단기적 조절을 위한.baroreflex system뿐 아니라 cardiopulmonary reflex 메커니즘가지도 구현하여 모델에 포함시켰다. 또한 교감 및 부교감 신경에 의한 자극-반응 전달을 구현함에 있어 생리학적 데이터에 기초한 방법을 사용하였다. 본 연구의 수치해석 코드를 검증하기 위하여 우선 보통 상태의 심혈관계에 대하여 혈류역학적 계산 결과를 기존의 참고문헌들에서의 값들과 비교 검토하였다. 심혈관계 모델의 혈류역학적 자극에 대한 반응 결과를 조사하기 위하여. 20% 출혈이 발생하는 경우와 LBNP(Lower Body Negative Pressure) 모사를 수행하였다. 두 경우 모두. 비교적 실험치와 잘 일cl하고 있음을 확인할 수 있었다. 특히 LBNP 수행 시, 외부압력의 크기가 커질수록 baroreflex만을 포함하고 있는 방법은 baroreflex와 cardiopulmonary reflex 모두를 포함하고 있는 방법에 비하여 다소 부정확한 결과를 보여주고 있는데. 이는 cardiopulmonary reflex 메커니즘의 중요성을 보여주고 있다.

• Nuclear Engineering and Technology
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• 제27권4호
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• pp.483-490
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• 1995

PKL III A 4.4 실험은 "증기발생기 세관파열사고 후 소외전원 가용의 조건 하에서 발전소가 비상냉각수 주입없이 수작동에 의해 제어될 수 있음을 확인하는 것이다. 실험 모사에 따른 NLOOP Code의 제한이나 능력의 검증을 위해, 실험에서 얻어진 PKL 설비의 거동은 NLOOP의 결과와 상호 비교되었다. NLOOP 코드는 한국원자력연구소와 독일 SIEMENS/KWU사에 의해 Westinghouse 형 발전소의 과도현상 해석용으로 개발되었으며, PKL III 설비모사를 위해 적절히 수정되었다. 자연대류에 의한RCS Loop의 냉각수 유량과 격리된 RCS Loop에서의 자연대류 중단현상을 특별히 주의깊게 연구하였다. 실험과 계산 결과의 비교는 NLOOP 코드의 의사능가 문제점들을 보여준다.보여준다.

• 대한건축학회논문집:계획계
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• 제34권10호
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• pp.83-94
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• 2018

In many theoretical and empirical studies on the design issues of therapeutic healthcare facilities, spatial configuration that promotes users' wayfinding behavior, has been emphasized as a significant factor to mitigate stressful experiences and to enhance restorative quality in the healthcare environment. This is also applicable to the healthcare setting for children. However, not much evidence has been reported with regard to the relationship between spatial configuration and wayfinding behaviors in this specific setting. Moreover, healthcare facilities for children with physical disabilities need more attention to provide easy wayfinding due to various physical restrictions. The aim of this study is therefore, to unfold the relationship between spatial configuration and visual cognitive qualities of outpatient spaces in the selected children's rehabilitation hospitals in Seoul, by examining visual cognitive attributes such as visibility, accessibility, and intelligibility. In the first phase, the spatial layout of the hospitals was analyzed, with an emphasis on the major outpatient areas such as the entrance lobby, doctors' examination, and physical therapy zones. In the second phase, a space syntax tool was implemented to examine visual cognitive characteristics of the spatial configuration. The spatial configuration parameters measured were integration, integration core, visual isovist field continuity, correlation between integration and step depth, and the correlation between integration n and integration 3. As a result, the integration was higher in the hall type configuration. Circulation intersections acted mostly as integration cores for better visibility. Some areas showed the lack of continuity in the visual isovist fields overlap and irregular correlation between integration and step depth. The intelligibility was higher in the circulation area and social interaction spaces such as a cafe, reception waiting, and therapy waiting areas. Based on the analysis, design implication and possible future improvement were discussed to enhance wayfinding experiences in the hospitals for children with physical disabilities.

• 한국실내디자인학회논문집
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• 제20권6호
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• pp.262-271
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• 2011

The purpose of this study was to classify types of family visitors' behaviors more concretely, which could be useful in planning of exhibition spaces in a science museum, with given priority to their behaviors according to interaction between them, and to understand characteristics of the behaviors. With this view, the scope of this study was restricted to subjects, who were family visitors of Gwacheon National Science Museum, consisting of parents and their one elementary school child per family unit. For understanding their behaviors, itinerary tracking and observation method of behavior were conducted. Moreover, for understanding substantial types and characteristics of family visitors' behaviors, multivariate analysis was applied. Accordingly, the results of the study are as follows. First, as a result of factor analysis, two main factors were derived. In other words, they were 'Durability of viewing' as the first and 'Interactivity between family members' as the second, which were shown valid in classification of the types of their behaviors. Second, according to the factors derived, the types of their behaviors were classified into in-depth cooperative viewing, selective independent viewing, interest concentration child-led viewing and consideration parent-led viewing. They were shown valid in topological localization and classification, as a result of analysis of the main factors. Third, in view of common characteristics of the types, it is judged that active orientation prior to regular viewing could encourage visitors coming to the museum for the first time to feel more friendly to unfamiliar exhibition environments, during the initial seek time, and to reduce visual supersaturation. Fourth, it is judged that distributed arrangement of exhibits, which result in continuous standby, could avoid confused visitor circulation by the estimated time required for viewing.

• 한국실내디자인학회논문집
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• 제20권3호
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• pp.182-189
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• 2011

This research suggests a way of hygienic space planing of the customer space in the university student restaurant of E University in Seoul. For this study. the behavior observation in the restaurant was conducted in order to analyze the sequence of customer behavior related space planing applying HACCP (Hazard Analysis And Critical Control Point). Also the survey was conducted to analyze opinions of customers about hygiene of the space. The results of the analyses of the observation and the survey were similar in terms of hygiene. In conclusion, for hygienic space planing of the customer space in restaurant, the space circulation should be planned according to the hygienic sequence of customer behavior. The spaces in restaurant should be divided into two areas: the clean area and the contaminated area to prevent cross-contamination. The clean area, such as spaces preparing dishes and food including water and table hall where customers eat, should be separated from the contaminated area such as the spaces where waste is handled and where dirty dishes are kept. In order to prevent cross-contamination, hygiene facility to remove contamination should be located before going to the clean area. More specifically, the hygiene facility should be located between a cash counter and a space preparing dishes so that customers can wash their hands before they touch dishes. Space arrangement with feed-back process to check the possible points of cross-contamination and correct space arrangement until the possibility of cross-contamination is removed in the restaurant.

• 대한의용생체공학회:의공학회지
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• 제19권3호
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• pp.297-303
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• 1998

판막 후부의 공동부는 판막의 닫힘 거동과 판막 주위의 혈류 유동장을 변화시켜 인공 판막의 수력학적 성능에 영향을 미칠 수 있다. 계식 이엽 판막(SJMV), 폴리머 단엽 판막(MLPV), 폴리머 삼엽 판막(FTPV)을 판막 후부에 공동부가 있는 시험부와 공동부가 없는 직관형 시험부에 설치하여 모의 순환 장치에서 판막의 수력학적 성능을 평가하였다. 판막의 누수량은 공동부가 있는 시험부에서 약간 작았고, 수축기 평균 압력강하는 크게 나타났으나 통계적으로는 큰 차이가 없었다. 따라서 판막 후부의 공동부는 판막의 수력학적 성능에 큰 영향을 나타내지 않았다. 유량 파형의 해석 결과 판막 후부 공동부는 MLPV에서는 판막의 닫힘에 큰 영향을 주지 않았으나, SJMV에서는 판막의 닫힘이 일찍 시작하게 하였고 이 영향은 FTPV에서 더욱 크게 나타났다. FTPV는 공동부가 있는 시험부에서 역류 최대 유량이 감소하였으므로 판막 후두에 공동부는 판막의 급격한 닫힘에 의한 역류 제트의 발생을 감소시키리라 기대된다.

• 대한조선학회논문집
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• 제50권5호
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• pp.307-313
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• 2013

This paper presents a simulation for passenger ship evacuation considering determination of evacuating direction based on walking direction potential function. In order to determine walking direction of a passenger, his/her position in two dimensional plane was adopted as a design variable, and fixed boundaries such as walls and obstacles were adopted as constraints. To solve this optimum problem, a walking direction potential function was adopted as an objective function. This potential function was configured as a kind of penalty function and it contained two components. One is a potential function concerned with the distance to the destination, and other is a potential function based on the effect of walls and obstacles. To determine evacuating direction, this problem was solved by minimizing the walking direction potential function every unit time during the simulation. The crowd behavior of the passenger consisted of the flock behavior, a form of collective behavior of a large number of interacting passengers with a common group. With the proposed algorithm, the test problems in International Maritime Organization, Maritime Safety Committee/Circulation 1238(IMO MSC/Circ.1238) were implemented and the direction of passengers and total evacuation time was analyzed.

• 대한조선학회지
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• 제26권3호
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• pp.41-50
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• 1989

2차원 날개 단면 주위 유동문제를 포텐셜장에서의 표면양력판이론에 의하여 해석하였고 수치해석 효율을 증대시키기 위한 방법을 제시하였다. 날개 뒷날에서 유동이 쐐기 주위의 유동과 유사하다는 특성을 이용하여 계산효율을 증대시키기 위한 쐐기형 쿠타 조건(wedge type Kutta condition)을 제시하였다. 또한 쐐기형 계산효율을 증대시키기 위하여 세부 분할 방법을 적용하였다. 즉 날개 뒷날 부근의 4개의 양력판을 세분하고 세분된 양력판에서의 다이폴세기는 쐐기 주위 유동특성을 따르게 하였다. 세부분할 방법에 의한 쐐기형 쿠타조건을 2차원 날개단면 문제에 적용하였을 경우 수치계산 효율이 증가됨이 보였다. 날개 앞날에서의 유동은 앞날 반경(leading edge radius)을 갖는 원에 접하는 포물선(osculating parabola) 주위의 유동과 유사하다는 특성을 이용하여 비교적 적은 양력판 갯수에 의한 계산결과로부터 날개 앞날 주위의 유동을 정확히 계산하였다. 날개 앞날 주위의 급격한 유동변화를 정확히 계산함으로써 캐비테이션 발생 문제 및 날개 주위 경계층 문제를 계산하기 위한 정도 높은 입력자료를 제공할 수 있게 되었다.

• 대한지역사회영양학회지
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• 제7권4호
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• pp.506-515
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• 2002

This study examined the state of health and weight maintenance according to the body mass index (BMI) , and explored demographic variables, diet variables, the degree of stress etc. The results presented were based on data collected from 428 women who are mothers of the middle school children in Jeongeup city. Using SPSS WIN (Ver 9.0) , the frequency, percentage, mean, standard deviation, chi-square, ANOVA, and correlation analysis were provided. The mean of BMI for the subjects was 22.6, the ratio of obese women (BMI $\geq$ 25) was 22.9%. The frequency of the reported circulation or respiratory related diseases was greater in the obese group compared to the normal weight ($20 \leq BMI \leq 25$) or the lean (BMI < 20) groups. The obese group had less awareness of obesity. Those who regard themselves obese had lower rates of satisfaction with their body shape and higher rates of interest in weight control. Approximately 65% of the subjects attempted weight reduction more than once. Subjects who were obese had the most undesirable dietary behavior. In particular, this group had the higher rates of rushed meals, overeating, meals while watching TV or newspapers, and snacking, and eating out. In analyzing the correlation of variables influencing obesity, there were positive correlations between obesity and overeating, obesity and the degree of stress. Correlations between obesity and satisfaction for life found to be negative. Moreover, stress had a positive correlation with obesity and overeating, and showed negative correlation with eating behavior. Consequently, stress seemed to induce undesirable eating behaviors and increase obesity. Of the demographic background variables, subjects who were obese tended to be older, had lower levels of education, higher rates of employment, longer period of marriage, the higher number of children, preschool children or children preparing for highschool or college, lower satisfaction with children and household life.