• 한국시뮬레이션학회논문지
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• 제26권3호
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• pp.1-11
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• 2017

격실 내부에서의 폭발로 인한 인원의 피해를 분석하였다. 특히 격실 내에서 폭압 전파에 영향을 미치는 돌출된 장애물의 유무에 따른 인원 피해를 비교하였다. 격실 내에 장애물이 없는 경우에 경험적 고속처리모델을 이용하여 폭압을 예측할 수 있다. 하지만 격실 내부에서는 폭압 프로파일이 개활지에서와 달리 복잡하며 의자와 같은 구조물이 존재하는 경우에는 경험적 고속처리모델 적용이 불가하다. 따라서 장애물이 있는 격실 내부 폭압은 유한요소해석을 이용해 획득하였다. 또한 개활지의 폭압 프로파일을 기준으로 개발된 Friedlander 압력-충격량 곡선을 격실 내부에서의 복잡한 폭압 전파로 인해 피해평가에 적용할 수 없어, Axelsson 단자유도 모델을 적용하여 인원 피해를 분석하였다. 장애물이 있는 경우 인원의 흉벽 속도는 26에서 76 퍼센트(%) 만큼 감소되었으며 격실내 인원피해 또한 감소되었다.

• 한국건축시공학회지
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• 제20권4호
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• pp.375-382
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• 2020

국내 국경 지역의 주요 도로에 낙석 장애물을 설치, 운영하여 적군의 이동을 방지하고 차단하고 있다. 그러나 접경지역의 개발로 인한 교통량 증가는 낙석으로 인한 도로 교통 혼잡, 교통 안전, 도시 미관 저하 등 많은 문제를 야기하고 있다. 따라서 본 연구는 단위별로 다르게 적용되는 낙석장해물 철거 및 교체 시설 설치 지침을 제공하고, 운영에 필요한 낙석 장해물 유지비에 대한 국방부의 정책 방향을 제시하고자 하였다. 본 연구에서는 낙석 장해물 제거 및 대체시설 설치에 관한 지침 연구의 일환으로 필수 낙하 장해물에 대한 표준 단가를 제시하여 암석 제거 여부를 판단 할때 판단 자료로 활용하고자 하였다.

• 한국건설관리학회논문집
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• 제14권5호
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• pp.113-121
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• 2013

CM기업의 해외진출이 중요한 화두가 되고 있는 현 시점에서, 본 연구는 CM기업이 해외 CM사업에서 겪는 애로요인(어려움)을 도출하고 이들 애로요인에서 나타나는 주요 특징과 시사점을 분석하기 위한 목적으로 수행되었다. 해외 CM사업 경험이 있는 CM전문가들을 대상으로 설문조사와 인터뷰조사를 실시하여 해외 CM사업의 5개 애로요인군(群)과 25개 애로요인에 대한 분석을 실시하였다. 그 결과, 해외 CM사업에는 다양한 유형의 애로요인들이 존재하지만 각 애로요인에는 경중(輕重)이 있으며, CM기업들이 우선적으로 주목하고 대비해야할 소수의 애로요인이 있는 것으로 나타났다. 또한, CM기업이 해외 CM사업에서 겪는 어려움을 최소화하기 위해 해결해야 할 가장 중요한 현안은 CM전문가 양성 및 확보를 통한 시공이전단계 사업관리역량 강화인 것으로 나타났다.

• 대한수학교육학회지:수학교육학연구
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• 제20권3호
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• pp.305-322
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• 2010

평면도형의 넓이 학습에서 나타나는 인식론적 장애의 유형은 크게 측정의 속성과 관련된 장애, 단위정사각형 개념과 관련된 장애로 나눌 수 있다. 먼저, 측정의 속성과 관련된 장애의 원인은 길이와 넓이 개념 사이의 혼동, 도형 영역과 측정 영역에서 정의하는 방법상의 혼동 때문이며, 둘째, 단위정사각형 개념과 관련된 장애의 원인은 학생들에게 단위정사각형이 넓이의 기본단위로 인식이 잘 안되기 때문이며, 2 차원적 평면의 개념이 불완전하게 정착했기 때문이다. 이에 따라, 넓이에 대한 측정의 속성과 관련된 장애 현상의 교정적 지도 방안은 두 속성간의 관계를 살펴볼 수 있는 활동을 제시하고, 측정의 개념으로 넓이를 정의할 필요가 있으며, '정렬(array)'의 개념으로 넓이공식을 유도하고, 통합적으로 공식을 적용하도록 지도할 필요가 있다. 한편, 단위정사각형 개념과 관련된 장애 현상의 지도방안은 각 단계를 충분히 활동할 수 있도록 넓이를 구하고자하는 도형의 소재 및 형태를 다양하게 제시할 필요가 있으며, 넓이에 대한 연속량적 개념을 인식하도록 교수학적 방안을 구안해야 한다.

• 한국식품조리과학회지
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• 제23권2호통권98호
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• pp.195-204
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• 2007

The objective of this study was to analyze dietitians' sanitary practices and perceptions of obstacles according to HACCP. Questionnaires were administered to 94 elementary school dietitians in the Gwangju and Jeonnam Regions of South Korea. The data were evaluated by a 5 scale Likert method and statistically analyzed The results of the study are as follows. Each subject was generally characterized as a university graduate 79.8%, with 10 to 15 years experience 37.6%, and in her mid to late thirties 39.4%. We found that direct management was the highest occurring form of food service system 96.8%. With regards to the type of food service operation quantitative service as 60.6%, and partial self-service was 30.9%, 89.4%of all served only lunch. In all, 93.6% of the teams collaborated, while their organic collaboration was 64.9%. When HACCP was applied, sanitary practices scored an average of 4.83, which was significantly higher than 4.62 when HACCP was not applied. The dietitians' perception of sanitary practices was as very high 4.75 of 5. Sanitation, in regards to food management, scored 4.89 among the detailed items. This proves that in relation to food management, sanitation is considered most important. When HACCP was not applied, the perception of obstacles was, on an average, 3.07, which was higher than 2.74 when HACCP was applied. The results for the detailed items, which focused on sanitary practices and different perceptions of obstacles according to HACCP, were as follows. When HACCP was applied, a high mean of 3.32 occurred for facilities and utilities shortages followed by degree of cooperation at 3.22, and then monitoring at 3.01. The item that dietitians viewed as the biggest obstacle was lack of departmental budget support (M=3.46). Other serious obstacles were facilities, facility sanitation, and utility shortages (M=3.38), as well as the aappropriateness of machines and cooking utensils and arrangements in the dining room (M=3.28). Stepwise multiple regression was used to better understand how much these perceptions of obstacles would influence sanitary practices when HACCP was applied. The item analysis of the HACCP obstacles proved that persons involved in food service, except the food service employees, didn't cooperate enough with their food service employees. As a result, this lack of cooperation had a negative effect on sanitary practices. Accordingly, it is necessary to determine the causes of for lack of cooperation and attract the active attention of those involved.

• 대한간호
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• 제19권5호통권108호
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• pp.55-68
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• 1980

The purpose of this study is to find out most wanted nursing contents (behavior) of the dying patient and his family and to discover the obstacles to helping the dying as analysis of 53 factual reports on the care of dying patients on American Journal of

• 산업융합연구
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• 제8권2호
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• pp.9-25
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• 2010

Attachment to a parents during the childhood has a impact on the number of friend and the quality of friend-relations. Specially, reactions for attachment-obstacles can be reduced by depending on the parent's positive attitude for child.

• 한국가스학회지
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• 제12권1호
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• pp.54-61
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• 2008

Experimental investigations were performed to assess the influences of different multiple obstacles on flame propagation in a rectangular confinement. Three different multiple obstacles were used: circular, triangular and square cross-sections with blockage ratios of 15% and 30%. The same method described in Park et al. [13] to investigate the interaction between the propagating flame and the obstacle was applied. Before the freely propagating flame impinged on the obstacle, the flame propagation speed remains close to the laminar burning velocity, regardless of the obstacles used. The reported data revealed that the trend in increase of the local flame propagation speed is a result of the interaction between the obstacle and the propagating flame front behind the obstacle. The local speed was found to increase from a circular to a triangular and a square obstacle. The mean flame speed was found to be less dependent on both the obstacle types and the different blockage ratios used.

• 한국안전학회지
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• 제27권6호
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• pp.70-77
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• 2012

Experimental investigations were performed to examine the characteristics of propagating flame fronts around multiple bars within a rectangular chamber. The explosion chamber is 400 mm in height, $700{\times}700mm^2$ in cross-section and has a large top-venting area, $A_v$, of $700{\times}210mm^2$. This results in a value of 0.44 for $A_v/V^{2/3}$ and a L/D value of 0.57. The multiple obstacles of length 700 mm with a blockage ratio of 30 % were placed within the chamber. Temporally resolved flame front images were recorded by a high speed video camera to investigate the interaction between the propagating flame and the obstacles. Results showed that the flame propagation speeds before the flame impinges onto the obstacle almost equal to the laminar burning velocity. As the propagating flame impinged on the obstacle, the central region of flame began to become concave, this resulted in the flame deceleration in the region. As the flame interacted with the modified flow filed generated behind the central obstacle, the probability density functions(PDFs) of the local flame displacement speed were extensively distributed toward higher speeds.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1491-1495
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• 2004

For the evaluation of the mobile robot performance in complex environments, the experimental approach in an actual physical environment has been commonly taken. In the physical experimental approach, however, it is quite difficult to define the proper environment for the evaluation due to the lack of commonly agreed characteristics of the test environment. Particularly the number of combinations of types and physical parameters of the obstacles that the mobile robot is expected to deal with is practically unlimited. In an effort to simplify and improve the effectiveness of the evaluation process, we propose an evaluation method using decomposed environmental elements, where we evaluated the performance of the robot for a small group of simple and decomposed obstacle components, for examples projection and slope, instead of a large group of complicated random obstacles. The paper describes a set of simple obstacle models and performance parameters that we have chosen for the effective evaluation process. As an alternative to the physical experimental evaluation approach, in this paper, we used a virtual evaluation environment where the robot and the physical test environment has been modeled using a commercial multi-body dynamics analysis packaged called RecurDyn.