• 한국산업융합학회 논문집
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• 제26권2_2호
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• pp.333-340
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• 2023

Environmental regulations are being strengthened worldwide to solve global warming. For this reason, interest in eco-friendly gas fuels such as LNG and hydrogen is continuously increasing. However, when adopting eco-friendly gas fuel, liquefying at a cryogenic temperature is essential to ensure economic feasibility in storage and transportation. Although austenitic stainless steel is typically applied to store cryogenic liquefied gas, structural steel can experience sudden heat shrinkage in the case of leakage in the loading and unloading process of LNG. In severe cases, the phase of the steel may change, so care is required. This study conducted Charpy impact tests on steel material in nine different temperature ranges, from room to cryogenic temperatures, to analyze the effects of cryogenic liquefied gas leaks. As a result of the study, it was not easy to find variations in ductile to brittle transition temperature (DBTT) due to the leakage of cryogenic liquefied gas. Still, the overall impact toughness tended to decrease, and these results were verified through fracture surface analysis. In summary, brittle fracture of the steel plate may occur when a secondary load is applied to steel for hull structural use exposed to a cryogenic environment of -40 ℃ or lower. Therefore, it needs to be considered in the ship design and operating conditions.

• 환경영향평가
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• 제20권3호
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• pp.313-324
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• 2011

The purpose of this study is to present the raw data for establishing the plan of top soil conservation in soil environment and preventing the soil loss by establishing the potential amount of soil loss using RUSLE. The results are as follows. To apply the RUSLE model, we calculated the potential amount of soil loss by using 5 factors; rainfall erosion factor(R), topographical factor(LS), soil erosion factor(K), land cover factor(C) and erosion control factor(P). The assessment map of soil loss was drawn up by classifying 5 grades. According to the soil loss estimation by the RUSLE, it showed that approximately 83.9% of the study area had relatively lower possibility of soil loss which was the 1 ton/ha in annual soil loss. Whereas, the 7.0% of the study area was defined as high risk area which was the 10 ton/ha in annual. Therefore, this area was needed that there was environment-friendly construction of farm land, improvement of cultivation environment and so forth. In future, if we will analyze the amount of soil loss of Gyeongju national park and Hyeongsan river watershed, we will offer the help to establishing the conservation plan of soil environment in Gyeongsangbuk-do.

• 한국환경복원기술학회지
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• 제21권6호
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• pp.1-13
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• 2018

Mapping radiation heat flux of urban area is essential for urban design and landscape planning. Because controlling urban geometry and generating green space are important urban design strategies for reducing urban heat, urban planner and designer need to recognize the micro urban heat distribution for adequate urban planning. This study suggests a new methodology for mapping urban radiation heat flux in a micro scale considering buildings and trees' shade. For doing that, firstly, we calculate net radiation for each urban surfaces (building, road (not shaded, building shaded, tree shaded), ground (not shaded, building shaded, tree shaded), tree (not shaded, building shaded)). Then, by multiplying the area ratio of surfaces to the net radiation, we can obtain the radiation heat flux in micro-scale. The estimated net radiation results were found to be robust with a $R^2$ of 90%, which indicates a strong explanatory power of the model. The radiation heat flux map for 12h $17^{th}$ August explains that areas under the building and tree have lower net radiation heat flux, indicating that shading is a good strategy for reducing incident radiation. This method can be used for developing thermal friendly urban plan.

• 한국조경학회지
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• 제30권2호
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• pp.70-78
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• 2002

The landscape disign of Gamcheon wholesale fish Market was designed around a turnkey base to promote the economy of Busan Metropolitan City, to establish a fishery marketing center and to modernize existing facilities. The objectives of the project were to promote the mood of an old market, while preserving its functions and efficiency as a market, to design outdoor spaces with natural resources and amenities in balance, and to create attractive tourist spots in connection with the wide area development plan. The project was oriented, fast, to enhance the functions of the market. For this purpose, a multi-dimensional space layout was designed in consideration of functions as a wholesale market. The safety of pedestrians was secured by separating lathes for vehicles and for pedestrians. Tree planting with various functions such as sheltering, wind breaking and guiding was planned. Secondly, nature-friendly and human-friendly landscaping design was attempted. For this, the beautiful natural resources of Amnam Park were utilized, and green spaces such as green bridges linking buildings in the wholesale market, and rooftop gardens were to be arranged. In addition, environment-friendly facilities such as roads paved with natural materials(i.e. gravel, shells) and program parking lots were to be planned. Thirdly, landscape design was considered to create attractive tourist spots. For example, a fish farm was created as a theme street for pedestrians and various water-friendly spaces such as pedestrian ramps, observatories and seaside streets were to be secured. The main contents are as follows. First, a green bridge to Ahnnam Park was introduced for a tour source and flower garden, an event plan and viewing deck open to the sea were planned on the bridge's axis. Secondly, for the effective land use plan concerning open space and convenience to visitors, a promenade was planned, which is connected with the theme plaza and small plazas by environmental sculptures in front of the market hall and at the gate. As well, an observatory and a roof garden help create three dimensional multi leveled space, with a good view of the natural landscape of the sea, sky and park Thirdly, landscape materials, such as trees and those for facilities, strengthened for protection against the seawind and salt damage were selected. The commercial market area was intended to be transformed a traditional functional area of efficiency and economy into an attractive marine leisure area where both tourists and neighbors can make use of it.

• 한국건설관리학회논문집
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• 제16권6호
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• pp.124-135
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• 2015

세계적으로 환경오염문제가 대두되면서 국내에서도 정부와 민간차원에서 친환경건축을 위한 노력이 활발히 진행 중이다. 하지만 건축물의 친환경 성능 및 친환경 관련 법규 및 기준 등에 대한 평가환경은 2차원기반의 수작업을 통한 평가로 진행되기 때문에 시간, 비용, 노동력 등이 많이 소요되며 평가의 정확성 및 효율성을 확보하기 어렵다. 따라서 본 논문에서는 개방형BIM기반으로 친환경건축 관련 인허가 업무의 개선을 목적으로 친환경건축 관련 인허가 조건 중 에너지성능지표 평가항목과 IFC포맷의 데이터와 연계를 통한 평가방안 모색하고 발생하는 문제점에 대한 대안을 제시하며 이를 반영한 평가프로그램의 활용으로 평가 프로세스를 제시함으로써 개방형BIM기반으로 에너지성능지표의 평가를 자동화하는 방안을 제시한다. 본 연구에서 제시된 방안을 친환경건축 관련 인허가 업무에 적용함으로써 업무절차의 간소화와 자동화를 통한 시간, 비용, 노동력의 절감을 기대할 수 있으며 설계변경 시 요구되는 절차가 단순화되어 업무의 생산성과 효율성이 향상되며 검토과정과 결과 값의 투명성과 검토의 정확성과 신뢰도를 확보 할 수 있을 것으로 기대한다.

• 한국조경학회지
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• 제38권4호
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• pp.45-53
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• 2010

본 연구는 유비쿼터스 환경에서 참여형 환경조형물의 이용자 만족도에 관한 연구를 통하여 앞으로 유비쿼터스 시대에 이용자들이 사용하게 될 환경조형물에 대한 만족도의 체감을 높이기 위한 사용성과 서비스, 기능성, 조형성에 대한 유비쿼터스 도시 공간 속에서의 U-환경조형물의 좀 더 발전적인 방향을 제시하고자 강남대로 U-Street에 설치되어진 U-환경조형물인 미디어 폴을 조사 대상지로 선정하였다. 연구결과를 요약하면 다음과 같다. 유비쿼터스 환경에서 시작단계의 환경조형물인 미디어 폴의 부문별 만족도 중에서 서비스 만족도, 기능성 만족도, 조형성 만족도와 미디어 폴의 종합적인 만족도로 설정한 후 조사 분석하여 만족도 연구를 수립하였다. 미디어 폴의 부문별 만족도에서 서비스 만족도는 대중교통 안내도, 기능성 만족도는 거리문화의 촉매제, 조형성 만족는 '형태성', 미디어 폴의 부문별 만족도와 종합 만족도 관계에서 기능성 만족도가 가장 큰 영향을 주는 것으로 나타났다. 이는 미디어 폴의 만족도에 가장 큰 영향을 주는 요인으로 나타난 만큼 도시공간에서 U-환경조형물의 만족도의 체감을 높이기 위한 미디어 폴의 다양한 컨텐츠 개발과 사용, 편리한 기술개발, 미디어 폴의 기능성 만족도에 대한 지속적 연구와 강남의 랜드 마크가 되기 위해서는 시민들과 소통하기 위한 즐거움과 감동을 줄 수 있는 스토리가 담긴 인간 중심의 기능성 요소 개발이 중요할 것이다. 현재 유비쿼터스의 초기단계는 가로 경관으로서 자연성이 결여, 환경조형물의 외피에 대한 개발, 인간에게 감동을 줄 수 있는 스토리텔링의 부재, 기술적 측면 부족, 수익성을 낼 수 있는 다양한 컨텐츠 개발, 투자에 비해 수익성 창출의 어려움, 사회소통 매개로서의 기능 등의 문제점을 보완해야 하며, 첨단 기술만이 아니라 경제적, 사회적, 문화적 측면을 고려한 똑똑한 기술보다는 편안하고 친인간적 기술로서 공간개발과 U-환경조형물의 설치가 요구되어야 할 것이다.

• 한국해양공학회지
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• 제35권1호
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• pp.50-58
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• 2021

The demand for eco-friendly energy is expected to increase due to the recently strengthened environmental regulations. In particular, the flow inside the pipe used in a cargo handling system (CHS) or fuel gas supply system (FGSS) of hydrogen transport ships and hydrogen-powered ships exhibits a very complex pattern of multiphase-thermal flow, including the boiling phenomenon and high accuracy analysis is required concerning safety. In this study, a feasibility study applying the boiling model was conducted to analyze the multiphase-thermal flow in the pipe considering the phase change. Two types of boiling models were employed and compared to implement the subcooled boiling phenomenon in nucleate boiling numerically. One was the "Rohsenow boiling model", which is the most commonly used one among the VOF (Volume-of-Fluid) boiling models under the Eulerian-Eulerian framework. The other was the "wall boiling model", which is suitable for nucleate boiling among the Eulerian multiphase models. Moreover, a comparative study was conducted by combining the nucleate site density and bubble departure diameter model that could influence the accuracy of the wall boiling model. A comparison of the Rohsenow boiling and the wall boiling models showed that the wall boiling model relatively well represented the process of bubble formation and development, even though more computation time was consumed. Among the combination of models used in the wall boiling model, the simulation results were affected significantly by the bubble departure diameter model, which had a very close relationship with the grid size. The present results are expected to provide useful information for identifying the characteristics of various parameters of the boiling model used in CFD simulations of multiphase-thermalflow, including phase change and selecting the appropriate parameters.

• KIEAE Journal
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• 제8권1호
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• pp.81-86
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• 2008

Due to the recent environmental problems, lots of studies on the solutions to reduce the environmental pollutions are on the way. In the field of construction, concrete that we are currently consuming approximately 1 ton each year is the most common and cheap building material. We must cut down on this preoccupied use of this material and develop an alternative material as recommended by the late environmental standards. In this regard, this study propose the 'yellow soil' as the main substance that composes the final state, 'yellow soil concrete'. This study also aims to analyze the physical and chemical performances of this concrete mixed with the yellow soil by comparing it with the cement and assesses the possibility of its application to the cement. The results of the experiment shows that, assuming the solidity of the cement concrete to be around $210kg/cm^2$ (20.58MPa), the solidity of the yellow soil combined material may be around 45%~55% in terms of the range of W/B use, 200 to 400 in the per unit fission amount and less than 2% in the addition proportion of admixing agents. But the scope of the optimal concoction amount of the yellow soil concrete should better be limited as following. 40% to 50% in W/B, 300 to 400 in the per unit fission amount and less than 2% in the addition of admixing agents.

• KIEAE Journal
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• 제10권1호
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• pp.91-96
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• 2010

Incheon Free Economic Zone's Songdo Area is a newly constructed city built on land reclaimed from the seaside and the surrounding area. Yeongjong Area is made after Land reclamation between Yeongjong Island and Yongyou Island began in November 1992. The first phase linking these islands to create the Incheon International Airport (phase 1) and the Airport Town Square community was finished in March 2001. However, if we take a look at the overall status of the project as it is carried on at present, it is hard to deny that the project is trapped inside the same legal restrictions as are all other existing cities, which permits Songdo Area and Yeongjong Area to meet only very minimum standards. This study intends to analyze and assess the Incheon Free Economic Zone's Songdo Area and Yeongjong Area of environmentally friendly construction and to rate its current development status, exposing any problems and offering alternative solutions. In this paper, the current state of constructions in Songdo Area and Yeongjong Area were reviewed. Then a quantitative analysis and assessment for the Songdo Area and Yeongjong Area constructions of apartments, complex buildings, office buildings, school facilities, store and hotel facilities were conducted by using green building certification criteria. Finally the synthetic results of environmental performance evaluation for Incheon Free Economic Zone's Songdo Area and Yeongjong Area constructions and follow-up suggestions were described.

• 한국BIM학회 논문집
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• 제5권4호
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• pp.30-36
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• 2015

The Leadership in Energy and Environmental Design (LEED) has provided abundant resources and guidelines for a new project to become a sustainable anchor in the neighborhood. Paired with a range of checklist, LEED has strong influence on the standards for a sustainable building, and it also has played an iconic role in energy-efficient architecture. However, it is still unclear as to whether or not an LEED certified building enhances environmental benefits to its surroundings. If an LEED certification promises a baseline for an eco-friendly building, then a group of these structures should ensure significant environmental benefits to the society. This is the main question of this study, and the authors answer this hypothesis by examining the relationship of LEED certificates and their influence on outdoor temperature, especially in terms of urban heat island effect. The goal of this paper is to analyze the influence of the LEED certification on urban temperature as an indicator of sustainable architecture's regional interactions. If an LEED certificate is regarded as a strong contributor to a sustainable built environment, then a group of these certificates should result in greater benefits to society. To this extent, the authors question if there is any possible relationship between a large concentration of LEED certified sites and the temperature of their surroundings. To properly assess the research direction, Global Moran's I analysis, Local Moran's I analysis, and Hot Spot analysis are implemented to find the clustered areas of LEED certified buildings. For examining relationships between clustered area and its temperature, correlation efficients are calculated.