• Transactions of the Korean hydrogen and new energy society
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• v.26 no.1
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• pp.15-20
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• 2015

During the liquefaction of hydrogen, the ortho hydrogen is converted into the para form with heat release that evaporates the liquefied hydrogen into the gaseous one backwards. The ortho-para conversion catalysts are usually used during liquefaction to avoid such boil-off. In order to compare and analyze the performance of the ortho-para hydrogen conversion catalysts, in-situ FT-IR device was designed and manufactured to measure the para hydrogen conversion rate in real-time. $LaFeO_3$ and $La_{0.7}Sr_{0.3}Cu_{0.3}Fe_{0.7}O_3$ perovskite catalysts were prepared by the citrate sol-gel method and their spin conversion characteristics from ortho to para hydrogen were investigated by in-situ FTIR spectroscopy at 17K. It was found that the spin conversion was affected by surface area, particle size, and crystallite size of the catalysts. Thus, the $La_{0.7}Sr_{0.3}Cu_{0.3}Fe_{0.7}O_3$ perovskite catalyst that had higher surface area, higher crystallite size, and smaller particle size than $LaFeO_3$ showed the better spin conversion property of 32.3% at 17K in 120min interaction with the perovskite catalysts.

• Journal of the Korea Convergence Society
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• v.11 no.1
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• pp.247-257
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• 2020

The purpose of this paper is to review the performance of the Green Village Project during the last 10 years, and examine the possibility of the institutionalization of a local governance. The Green Village Project was first initiated by an environmental movement group in Cheongju City, and now various actors, including Cheongju City and City Council members, public organizations, professionals etc, are participating. The project has been continuously and stably carried out for 10 years, and the participants now recognize that the project should be carried out every year. According to the analysis, the participants recognized the project as beneficial project for them on the basis of the rational choice. And the participants recognized the project as having legitimacy, and accumulating 'trust' between participants, accumulating the experiences of success. In conclusion, the sustainability and stability of the project has been strengthened, and the institutionalization possibility of the governance of the Green Village Project has been increased continuously.

• Journal of Forest and Environmental Science
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• v.31 no.4
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• pp.288-296
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• 2015

In many very high density cities in Asia in which there is limited area to expand, growth is forced upward as well as outward. Densely packed detached houses and low-rise buildings are replaced by lower density high-rises, leaving open spaces between high-rise buildings. Through this process, areas that formerly did not have much green space gain valuable green spaces, and new ecological corridors and patches are created. In this study, the demographic and housing-type changes of Wonju City were delineated using land use maps, aerial images, census data, and other administrative data. Green area changes were calculated using land cover data derived from multi-year Landsat TM satellite imagery. The values were then compared against demographic and housing-type changes for each administrative unit. The overall results showed a decrease of forested area in the city and an increase of developed area. Urban sprawl was clearly visible in many of the suburban areas. However, as expected, we also detected areas in which greenness did not decrease when the population greatly increased. These areas were characterized by residential building complexes of ten or more stories. If an equal number of housing units had been built as detached houses, these areas would not have kept as much green space. Our research result showed that high-density and high-rise residential structures can offer an alternative means to protect or create urban green spaces in high-density urban environments.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.11a
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• pp.100-103
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• 2009

The impermeable area on the surface of city has been increased as buildings and artificial landcover have continually been increased. Urban development has gradually decreased the green zone in downtown and alienated the city from the natural environment on outskirt area devastating the natural eco system. There arise the environmental problems peculiar to city including urban heat island phenomenon, urban flood, air pollution and urban desertification. As one of urban plans to solve such problems, green roof system is attracting attentions. The purpose of this study was to investigate the heat reduction effect according to the development of green roof system and to quantify the heat reduction effect by analyzing through simulation the heat environment before and after green roof system. For thermal environment analysis, Thermo-Render 3.0 was used that was developed by Tokyo Industrial College to simulate. The simulation showed that the heat island index before and after the development of tree-planting on rooftop changed maximum $0.86^{\circ}C$ and the surface temperature changed about $20^{\circ}C$. Only with lawn planting, heat reduction effect was great and it means that the green roof system in low-management-light-weight type is enough to see effect. The simulation identified that only lawn planting for green rooftop brought such difference and could lower the heat island index at a narrow area. It is judged that application of green roof system to wider areas might relieve urban heat island phenomenon positively.

• Land and Housing Review
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• v.3 no.3
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• pp.271-278
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• 2012

The climate change and global warming has been a world-wide issue. Also, the green growth has been a widely adopted strategy for national and regional development. In particular, after the Kyoto Protocol to United Nations Framework Convention on Climate Change was declared, the low carbon society was inevitable phenomenon. The hydrologic cycle in urban catchment has been changed due to the expansion of impervious area by rapid urban development. This paper has examined the Water cycle planning elements for green city in the scale of urban planning as well as site planning including housing site. In this study, the SWMM5-LID (Storm Water Management Model5-LID) model was used to simulate the hydrologic cycle of the test catchment as a typical urban catchment. We performed continuous simulation on urban runoff before and after the development of the test catchment and after the installation of Green city planning Elements.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.24 no.6
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• pp.109-119
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• 2021

Thermal environment of city is getting worse due to severe urban heat island caused by climate change and urbanization. Green roof improves the urban thermal environment and save the cooling energy in buildings. This study presented a green roof combined with a storage system that stores rain-water and supplies water through a wick and evaluated the temperature reduction effect as surface temperature and amount of evapotranspiration. For about a week, the surface temperature using a infrared thermal imager and the evapotranspiration by recording change of module weight were measured at intervals of 30 minutes from sunrise to sunset. The results show that the mean surface temperature of the green roof was 15.4 degrees lower than that of the non-green roof from 12:00 P.M. to 14:00 P.M. There was no significant difference between mean surface temperature of green roof with and without storage system immediately after rain, but more than a week after rain, there was a difference with average of 2.49 degrees and maximum of 4.72 degrees. The difference in daily amount of evapotranspiration was measured to be 1.66 times on average. As drought stress increased over time, the difference in daily amount of evapotranspiration and surface temperature between with/without storage system increased simultaneously. The results of the study show a more excellent cooling effect of green roof combined with the rainwater storage system.

• Journal of Ecology and Environment
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• v.35 no.2
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• pp.141-147
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• 2012

The rapid urbanization in developing countries is accelerating both the depletion and fragmentation of urban green space, despite the known positive effects of green spaces on the environmental conditions in cities and the quality of life of residents. Consequently, there is a need for practical tools that can support the development of networks of urban green spaces. This article presents a study that used a GIS-based least cost path (LCP) analysis to identify the best alternative for developing an urban green space network in the coastal city of Jakarta, Indonesia, which was based on the evaluation of topography and land use characteristics. Pair-wise analysis was used to reduce the sensitivity in the LCP model. The results showed that the coastal wetlands in the northern part of Jakarta and the agricultural fields in the suburban areas of Jakarta play an important role in connecting the green space network. On the other hand, some green spaces in the central part of Jakarta could not be connected by the LCP model. The method used in this study can serve as a tool to support the identification of networks of potential urban green spaces. It can also provide useful information for sustainable urban landscape planning and management in urban ecosystems. However, the inclusion of socio-economic criteria would further improve the model.

• Spatial Information Research
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• v.21 no.2
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• pp.99-106
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• 2013

Through the rapid economic growth, modern society have achieved the industrialization but needed to respond to climate change and low-carbon green growth on a scale of urban area. Many studies about the low-carbon city and the green city are on going, but most of them are not integrated but go along in each area(construction, transportation, energy, etc) In this paper, we surveyed the current status of researches about information system to design low-carbon city or green city, and define the method to integrate the outcomes from the each area. As a result integrated model of 'Low-carbon Urban Planning integrated System' in the paper, Individual system is developed by way of C/S form because web system raised problems for data load in analysis. The integrated system was decided to develop by way of Web form, and integrated system was developed by can use the analysed DB in the individual system. We expect this study can help future researches to develop more economical and efficient integrated information system model to design the low-carbon city and the green city.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• no.2
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• pp.178-184
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• 2004

The Yatomi - Aioiyama line is a city-planning road that was notified in 1957 and subsequently prepared by land readjustments. Currently, approximately 900m of road pass in the inside of the Aioiyama green area has not been constructed. The surveying briefing session for inhabitants was held in July 1992, the project was authorized by the Ministry of Land, Infrastructure and Transport in September 1993, and the project briefing session for inhabitants was held in September 1993. The site purchase has been completed. At the May 2000 briefing session, inhabitants of the area began voicing dissenting demanding the conservation of the natural environment of this green area. The inspector system serves as the third party, independent of both the administration and the inhabitants. Before finalizing the geometric line form of the road to be constructed, some surveys of animals and plants found along the walking trails carried out intensively in the northern area, which is approximately 50 ha, of the Aioiyama green area. The natural environment inspector submitted a plan for changing the geometric line form of the road decided upon by city planning, and it was approved by the city planning council. If the shelter structure or the retaining wall structure is adopted at the location where large slope faces are produced by excavation or landfill, and if the bridge structure is adopted at the place where stream-lines and walking trails intersect, it leads to a reduction of approximately $40\%$ in the areas for which change is planned. Furthermore, approximately $20\%$ of the area to be changed is restored by returning soil to the roof of the shelter.

• Magazine of the Korean Society of Hazard Mitigation
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• v.10 no.1
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• pp.11-16
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• 2010