• KIEAE Journal
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• 제14권2호
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• pp.11-19
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• 2014

Building energy consumption takes up almost 25% of the total energy consumption. Therefore, diversified ways, such as improving wall and window insulation, have been considered to reduce building energy consumption. Recently, green roof system has been explored as an effective alternative for dealing with reducing heating and cooling energy, thermal island effect and improving water quality. However, recent studies regarding a green roof system have only focused on building energy reduction without considering the applied usage, location, and story of the green roof system. Therefore, this study pays attention to the heating and cooling energy in relation to the applied usage, location, and story of a green roof system for investigating its impact on energy reduction. The result of simulations show that the reduction in heating energy consumption is higher when applied to Cherwon-gun province which has a continental climate condition, compared to the city of Busan that is distinguished by its warm climate. Cooling energy saving turns out to be higher when the green roof system is applied to Busan in comparison with Cherwon. As for the applied usage or function of the building, residential space acquires the highest heating and cooling energy saving effect rather than commerce, educational or office space because of HVAC's running time based on usage. When it comes to the story of the green roof, both heating and cooling energy saving become the highest when the green roof is applied to single-storied buildings. The reason is that single story building is affected by the ground largely. Generally, the variations of heating energy consumption are larger than the cooling energy consumption. The outcome of the simulations, when a green roof system is applied, indicates that the energy consumption reduction rate is dynamically responding to the applied usage, location, and story. Therefore, these factors should be counted closely for maximizing the reduction of energy consumption through green roof systems.

• 한국수자원학회논문집
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• 제36권4호
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• pp.623-631
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• 2003

본 연구에서는 유의파고별, 지오 튜브의 채움비, 지오 튜브 천단고의 변화에 따라 지오 튜브의 안정 및 소파성능에 관한 실험을 실시하였다. 축척은 1/50로 하여 조파 수로내에 모형을 설치하였다. 안정성 시험은 유의파고를 재현하여 지오 튜브의 변위를 계측하여 검토하였다. 지오 튜브의 각 부분의 변위량을 관찰하기 위하여 바닥에 메쉬를 설치하여 계측하였으며 지오 튜브 상부에 기준선을 표시하고 10cm 간격으로 초기 위치점을 설정하여 계측하였다. 소파성능은 지오 튜브의 설치전과 설치후의 각각의 채움비에 따라 천단고가 있는 경우와 없는 경우 파고전달율 해석하여 비교 분석하였다.

• Journal of the Korean Statistical Society
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• 제23권1호
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• pp.187-198
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• 1994

We derive a new Cramer-Rao type lower bound for the reciprocal of the density height of the median-unbiased estimators which improves most of the previous lower bounds and is attainable under much weaker conditions. We also identify useful necessary and sufficient condition for the attainability of the lower bound which is considerably weaker than those for the mean-unbiased estimators. It is shown that these lower bounds are attained not only for the family of continuous distributions with monotone likelihood ratio (MLR) property but also for the location and scale families with strong unimodal property.

• 대한치과기공학회지
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• 제6권1호
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• pp.15-18
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• 1984

A denture that shifts easily in response to latterally applied forces can cause a disruption in the border seal or prevent the denture base from Correctly relating to the supporting tissue. The factors that Contribute to stability include ridge height and conformation, base adaptation, residual ridge relationships, occlusion harmony, and Muscle control. These factors can be condensed into the following categories; 1. The relationship of the denture base to the underlying tissue. 2. The relationship of occlusal harmony. 3. The relationship of the denture surface and border to the surrounding muscle. 4. The location of artificial tooth.

• 한국기계기술학회지
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• 제13권4호
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• pp.57-62
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• 2011

In this study, a experimental work to investigate the influence of a turbulent wake flow on the velocity distribution of a diffuser with PIV method. The turbulent wake is generated by a rectangular prism, which is installed at the inlet of a diffuser. The results show that the velocity recovery of the subsonic diffuser is dependent on the height and location of rectangular prism. It is found that a certain height of the rectangular prism to generate the turbulent wake give a better velocity recovery, compared with no rectangular prism.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2009년도 추계학술발표대회 논문집
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• pp.33-36
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• 2009

Korea is the 3rd highest country in population density of the world,furthermore, 1/5 of Korean lives in Seoul with only 0.0% tiny area size. It explains the high-rise apartment has diffused so fast. Regardless of its height, almost all apartments have been planned in a very uniform way, ignoring the possibilities of vertical community and commercial culture. Since considerable number of residents have within building, ways to improve the community and commercial culture need to be explored. One major way to do is providing community space where residents are expected to use in a natural way. The purpose of this research is to identify preferred location of community space in each apartment building. Web guesting survey was used as main methodology. 83 data were collected during mid October, 2009. As results, lobby at the first floor was most favorably selected by super high-rise apartment residents due to convenience, accessibility.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 추계학술대회 논문집
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• pp.361-368
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• 1998

This paper sums up the study of the soundproof facilities to be placed on the test track section within the Seoul-Pusan H.S.T project. The objective of this study is to determine optimum design of soundproof including height, length, location, sound absorbing materials for test track(chonan-taejon). This paper shows the model to design the shape and materials of noise barrier for high speed trains(TGV, ICE, etc). Noise prediction is to be conducted by MITHRA. Various parameters affecting the noise propagation outdoors are surveyed and discussed in relation to H.S.T. noise.

• 한국안전학회지
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• 제24권6호
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• pp.93-102
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• 2009

Because steel girder bridge has big slenderness ratio, buckling is very important in design. Local buckling of plate girders having two longitudinal stiffeners in different positions under various load conditions is investigated. Various parametric study according to the change of web height, transverse stiffeners and load conditions are examined. These parametric studies are performed by numerical simulation utilizing finite element method. The objective of this study is to present the rational reinforcement location of two longitudinal stiffeners. The results of analysis are compared to that recommended by korean specifications for road bridges(2003).

• 한국조경학회지
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• 제31권5호
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• pp.20-30
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• 2003

This study is aimed at establishing the categories and items for ecological assessment and evaluation of the environmental friendliness of golf courses in the capital region of Korea. The categories and items for the assessment have been derived based on the existing literature and interviews with golf experts. This study covers 32 golf courses in the capital region of Korea that are available in terms of data and on-site surveys. In order to conduct a comprehensive assessment of the environmental friendliness of the golf courses, the assessment area was divided into 4 categories that include a total of 14 sub-categories. The 4 categories encompass 1) location, 2) topography, 3) vegetation, and 4) construction. As its sub-categories, the location category includes current land use and zoning in the National Land Use Management Law. Topography has 2 sub-categories in the damage ratio of existing topography, gradient, cut area, and slope height. The assessment of vegetation is largely based on site surveys in the categories of preservation of the existing vegetation, the use of natural resources and existing trees, the component ratio of native tree species, the multi-layered structure of vegetation, and the utilization of water purification plants. In the aspect of construction, afforestation on tile slopes and the utilization of existing surface soil were evaluated. The examination of comparative analysis among the 10 items as a ratio measure showed that the scores were low in the sub-categories of current land we, the use of existing trees, and the multi-layered structure of vegetation. However, the rating results were satisfactory in the 2 sub-categories including cut area, and the utilization of native tree species. Those proved to be contributing factors in the ecological health of the golf courses. According to correlation analysis of the 10 items to the overall ecological rating of each golf course, the sizes of the 32 golf courses were mainly affected by the damage ratio of existing topography, gradient, preservation of vegetation and slope height. This study has the initiative to conduct an ecological assessment of golf courses in the country based on site surveys. The study results revealed that location factors such as current land use, damage ratio of topography and gradient and topographical factors were the main factors affecting the environmental friendliness of golf courses. This indicates indicating the significance of these factors in the future construction practices of golf courses. Furthermore, this study raises the need for follow-up studies to establish more detailed assessment criteria and to develop assessment techniques for areas such as slope afforestation and water purification plants that need a qualitative approach.

• 감성과학
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• 제10권4호
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• pp.539-554
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• 2007

대형 비행기 조종사들은 지상으로부터 높은 조종실의 위치, 빠른 접근속도와 수직강하속도로 인하여 불충분한 시각정보를 바탕으로 착륙 조작을 하여야만 한다. 본 연구에서는 이러한 대형 비행기의 특징으로 인하여 비행기 착륙의 최종 조작인 당김(flare) 조작을 할 때 대형 비행기 조종사들이 정확한 높이지각을 하기 어렵다는 사실을 검증하였다. 연구 1에서는 조종석 외부로 보이는 공항에 대한 사진을 제시하고 높이 추정을 하도록 하여 정적 시각 단서만으로 정확한 높이지각이 가능한지를 살펴보았다. 85feet의 고도에서는 정확한 높이지각을 하나 당김 조작을 준비해야 하는 높이인 55feet부터 낮은 고도에서는 정확한 높이를 추정하지 못하였다. 연구 2에서는 착륙의 전 과정을 녹화한 화면을 보여주어 높이 추정을 하도록 하여 동적 시각 단서와 정적 시각 단서를 모두 제공하여 주었다. 시각단서가 연구 1보다 풍부하였으므로 50feet까지 정확한 높이지각을 하였으나 연구 1의 결과와 마찬가지로 당김 조작을 시작하는 높이인 30feet 이하의 저고도에서의 높이지각이 모두 부정확하였다. 시각 단서의 해석에 경험이 중요한 요인이므로 경험이 많은 기장과 경험이 적은 부기장 간의 높이 추정에 차이가 있는지를 연구 1과 연구 2에서 모두 비교하여 보았으나 차이는 유의하지 않았다.