• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.5
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• pp.69-83
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• 2012

Urbanization has caused increase of traffic jams, food shortage, housing, and environmental pollution in the world in recent decades. Urban agriculture, such as roof garden, can relieve the phenomenon of urban heat island causing from the urbanization. The study was conducted to investigate the characteristics of rooftop garden (farm) in 40 areas in Seoul, Korea, where the 'cabbage', 'lettuce', 'pepper', and 'mini-tomatoes' were the most preferred vegetables and fruit. The problems in the rooftop garden during a cultivation was observed for drainage system, soil management, cost or quality of planting mat and diseases and insects. The image of urban agriculture showed a positive words, such as 'bright', 'clean', 'open' and 'good' according to the survey.

• KIEAE Journal
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• v.13 no.6
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• pp.93-98
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• 2013

The purpose of this study is to analyze the rate of opening windows that makes residents of a flat-type apartment feel pleasant in summer time. A few conditions were simulated on the wind flow that pass through internal and external spaces of the flat-type apartment, utilizing CFX program. The simulation was made with the criteria for the rates of opening window at 20%, 50%, 70% and 100%. When the rate of window opening was more 50%, the wind speed(more than 1m/s) that makes the residents feel pleasant was observed in more 60% of the internal space. When the all windows of the apartments were opened, the heat island phenomenon was almost disappeared and the pleasant wind flow was more evenly distributed in the external spaces. If residents of apartments recognize the result of this study and practice in agrement on opening windows in summer, it is expected to contribute to minimizing the energy consumption for air conditioning.

• Journal of Forest and Environmental Science
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• v.34 no.3
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• pp.246-248
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• 2018

Urban development and population have augmented the increase of impervious land-cover. This phenomenon has amplified the effects of climate change and increasing urban island effects due to increases in urban temperatures. Seoul, South Korea is one of the largest metropolitan cities in the world. While land uses in Seoul vary, land cover patterns have not changed much (under 2%) in the past 10 years, making the city a prime target for studying the effects of land cover types on the urban temperature. This research seeks to generalize the urban temperature of Seoul through a series of statistical tests using multi-temporal remote sensing data focusing on multiple scales and typologies of green space to determine its overall effectiveness in reducing the urban heat. The distribution of LST values was reduced as the size of urban forests increased. It means that changing temperature of large-scale green-spaces is less influenced because the broad distribution could be resulted in various external variables such as slope aspect, topographic height and density of planting areas, while small-scale urban forests are more affected from that. The large-scale green spaces contributed significantly to lowering urban temperature by showing a similar mean LST value. Both of concentration and dispersal of urban forests affected the reduction of urban temperature. Therefore, the findings of this research support that creating urban forests in an urban region could reduce urban temperature regardless of the scale.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.2
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• pp.83-94
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• 2009

Environmental pollution becomes a serious problem in urban areas. Moreover, densely constructed strictures can be problematic to cities due to the rising temperature they cause as well as the increasing accumulation of air pollutants they generate by interrupting airflow. In order to improve residential amenity, it is necessary to improve the thermal environment by preserving wind corridors. To do so requires consideration to important aspects such as building arrangement, scale, vegetation, and land cover, which all have an effect on wind corridors. In this study, a typical arrangement-complex, which is the primary form of housing in Korea, was selected as a case ENVI-met. As a result of empirical analysis, the optimal apartment-complex arrangement that is most suitable for mitigating urban heat-islands phenomenon was determined, The outcome of this study can be utilized as a planning technique for apartment-complex construction in consideration to type of buildings, scale of buildings, and land cover.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.2
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• pp.223-230
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• 2009

Most urban water management systems are becoming vulnerable to flooding and drought due to the climate change (CC), urbanization and energy shortage. Despite of poor water management circumstances caused by extremely uneven annual rainfall and hilly terrain, traditionally we have made a sound and sustainable life based on our own philosophy and technologies which copes with our rigid environment. In this study a new paradigm of rainwater management is suggested and multipurpose and creative rainwater harvesting and management (RWHM) systems are introduced providing several case studies such as rainfall storage drainage (RSD) system, rainwater infiltration facilities and star city RWHM system. This new RWHM paradigm leads Seoul Metropolitan Government (SMG) in the Republic of Korea to change regulations and politics for the integrated RWHM. Finally, RWHM is expected to improve the safety, efficiency, energy consumption of urban water infrastructure, to reduce urban heat island phenomenon and, furthermore, to contribute in finding solutions for worldwide water issues and to adapt CC.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.1
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• pp.9-18
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• 2019

The intensity and the number of days of high temperature occurrence are also high and record heat occurred. In addition, the global warming phenomenon is intensifying globally, and especially in South Korea, the urban heat island phenomenon is also occurring due to rapid urbanization due to rapid industrial development. As the temperature of the city rises, it causes problems such as the comfort of the residential living and the cooling load. In this study, the cool roof performance is evaluated according to the roof color to reduce these problems. Unlike previous studies, UAV(Unmanned Aerial Vehicle) thermal infrared camera was used to obtain the surface temperature (white, grey, green, blue, brown, black) according to the rooftop color by remote sensing technique. As a result, the surface temperature of white color was $11{\sim}20^{\circ}C$ lower than other colors. Also air conditioning temperature of white color was $1.5{\sim}4.4^{\circ}C$ lower than other colors and the digital thermometer of white color was about $1.5{\sim}3.5^{\circ}C$ lower than other colors. It was confirmed that the white cool roof performance is the best, and the UAV and the thermal infrared camera can confirm the cool roof performa.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.6
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• pp.1-14
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• 2022

To alleviate the urban heat island phenomenon, this study aims to quantitatively analyze the effects of neighborhood green spaces on the improvement of the thermal environment based on detailed scenarios of five types of green spaces, including parks, pocket parks, parking lot greening, roadside planting, and rooftop-wall greening. The ENVI-met 4.4.6v model, a microclimate simulation program, was used to analyze the effects of green spaces. As a result, it was found that the air temperature decreased as the planting density of the park increased, but the thermal comfort index PET, which is the degree of heat sensation felt by humans, was not directly proportional to temperature. The establishment of a pocket park reduced air temperature up to a radius of 56m, while the range of temperature reduction increased by about 12.5% when three additional pocket parks were established at 250m intervals. Unlike the air temperature, PET was only affected in the vicinity of the planted area, so there was no significant difference in the thermal comfort of the surrounding environment due to the construction of pocket parks. Changing the surface pavement from asphalt to lawn blocks and implementing rooftop or wall greening did not directly act as solar shading but positively affected air temperature reduction; PET showed no significant difference. Roadside planting showed a higher air temperature reduction effect as the planting interval was narrower, but PET was not directly proportional to tree density. In the case of shrub planting under trees, it did not significantly affect the air temperature reduction but positively affected the improvement of thermal comfort. This study can outline strategies for constructing neighborhood green spaces to solve the urban heat island phenomena and establish detailed strategies for efficient thermal environment improvements.

• International Journal of Highway Engineering
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• v.13 no.3
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• pp.31-38
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• 2011

As the percentage of permeable ground is reduced due to the increased impermeable roads of major cities, a heat island phenomenon can be dominantly observed, resulting in increased temperature. In addition, rainfall that would have been naturally absorbed and retained by the permeable ground is overflowed due to large volumes of run-off water, resulting in more sewer failures and increased erosion. In terms of permeable pavement system, block paving has been used anywhere as well as provides many years of service. The permeable block paving is an effective alternative to the more traditional asphalt or plain concrete for minor roads; furthermore, it looks a lot better than other pavements. In this study, the functional drainage evaluation of block paving was carried out, considering the usage of experimental sludge and wheel tracking test, in order to simulate the field condition of roads.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.11a
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• pp.104-108
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• 2009

Rapid urbanization resulted in expansion of urban area and increase of population bringing deepened housing shortage. Supply-oriented housing policy made apartment a representative residential space in Korea in spite of the short history of apartment. This study analyzed the shape and arrangement of main building by year and the microclimate in the complex depending on the number of floors. The purpose of this study was to present the basic data in developing apartment complex to solve problems like the stagnation of pollution source and the rise of temperature due to the declined ventilation in apartment complex, and the worsened urban heat island phenomenon due to the impeded flow of wind. This study rearranged the shape and arrangement of main building by year and the tendency of the number of floors by year in the process of change, by generalizing the process of change of apartment complex, a representative modern residential space through preliminary research. Based on it, 8 object lot by age was selected and simulated by using Envi-met. Simulation identified that the change of apartment complex takes place having a positive effect on microclimate in the apartment complex and the microclimate in the apartment complex is influenced a lot by the shape of complex. If in future apartment complex plan, a systematic legal criteria of design is made about the shape and arrangement of main building, it might have a positive effect on the improvement of microclimate in the apartment complex, a representative residential space in Korea.

• Microbiology and Biotechnology Letters
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• v.46 no.2
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• pp.154-161
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• 2018

Currently, urban greening projects and research are attracting attention as a way to mitigate urban heat island phenomenon. In this study, nitrogen fixative bacteria were isolated and their effects on plant growth were confirmed. First, enrichment was performed in a nitrogen-free medium to isolate the nitrogen-fixing bacteria, and the colony showing high growth in a medium with limited nitrogen source was isolated and purified. Separated bacterial isolates were reduced by more than 90% acetylene by ARA and indirectly confirmed the activity of nitrogenase by ethylene production. Cedecea sp. MK7 and Enterobacter sp. Y8 with confirmed reproducibility were selected as nitrogen fixative bacteria. Nitrogen fixing bacteria were applied to the growth of perennial rye grass, and it was found that the dry weight increased to 34.80 mg (186.60%) compared with the control with 18.65 mg dry weight. After plant growth, microbial community analysis of soil applied by bacteria showed similarity to the control group. Therefore, in this study, it is expected that the efficiency will be increased if plant growth is promoted by using nitrogen fixing bacteria in urban greenery system.