• Journal of the Korean Institute of Gas
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• v.24 no.2
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• pp.22-28
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• 2020

In this study, quantitative risk assessment was carried out for city gas high-pressure pipelines crossing through urban rivers. The risk assessment was performed based on actual city gas properties, traffic volume and population and weather data in the worst case scenario conditions. The results confirmed that the social and individual risks were located in conditionally acceptable areas. This can be judged to be safer considering that the risk mitigation effect of protecting the pipes or installing them in the protective structure at the time of the construction of the river buried pipe is not reflected in the result of the risk assessment. Also, SAFETI v8.22 was used to analyze the effects of wind speed and pasquil stability on the accident damage and dispersion distances caused by radiation. As a result of the risk assessment, the safety of the pipelines has been secured to date, but suggests ways to improve safety by preventing unexpected accidents including river bed changes through periodic inspections and monitoring.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.3
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• pp.104-117
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• 1998

Rising concern about climate change has evoked interest in the potential for urban vegetation to help reduce the level of atmospheric CO\sub 2\, a major heat-trapping gas. This study quantified the functio of home energy savings and carbon emission reduction by shading, evapotranspiration and windspeed reduction of urban vegetatioin in Chuncheon. Tree and shrub cover averaged approximately 13% in residential land. The effects of shading, evapotranspiration and windspeed reduction annually saved heating energy by 2.2% and cooling energy by 8.8%. The heating and cooling energy savings reduced carbon emissions by 3.0% annually. These avoided emissions equaled the amount of carbon emitted annually from fossil fuel consumption by a population of about 1,230. Carbon emission reduction per residential building was 55kg for detached buildings and 872 kg for multifamily buildings. Urban vegetation annually decreased heating and cooling energy cost by ￦1.1 billions, which were equivalent to annual savings of ￦10,000 savings and carbon emission reduction due to tree plantings in the wrong locations, while windspeed reduction had a great effect. Plantings fo large trees close to the west and east wall of buildings, full tree plantings on the north, and avoidance of shade-tree plantings or selection of solar-friendlytrees on the south were recommended to improve the function of building energy savings and carbon emission reduction by urban vegetation.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.3
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• pp.285-293
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• 2005

This study was aimed at estimation of gas-particle partitioning of polychlorinated biphenyls (PCBs) in ambient air. The samples were collected at urban site in Japan from March 2002 to January 2003. The concentration of total PCBs (from 4 CB to 10 CB) and TEQ (Toxic equivalent) ranged from 62 to $247\;pg/m^3$ and from 2 to $14\;fgTEQ/m^3 $, respectively. The average contribution $(\%)$ of gas phase to total PCBs concentration was above $80\%$, which suggests that in the atmosphere PCBs predominantly existed in the gas phase. The weak correlations between total PCBs concentration and temperature was found. However this result was due to a typhoon during summer and raining during sampling period. The gas-particle partition coefficient (Kp) was obtained as a function of temperature. The partition ratio of gaseous and particulate phase PCBs can be estimated for an arbitrary temperature. The plot of gas/particle partition coefficient (log Kp) vs. sub-cooled liquid vapor pressure $(log\;P_L)$ had reasonable correlations for individual samples but the slope varied among the samples (coefficients of determination for log Kp versus log $P_L$ plot were> 0.76 $(p<0.0001)$, except for 3 samples). As a result, the variations in the slope among the sampling period may be due to change of temperature, raining during sampling period and wind in this study.

• Journal of the Korean Institute of Gas
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• v.22 no.6
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• pp.16-27
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• 2018

Since 2014, the Korean government has begun distributing LPG pipelines and LPG tankers to mountainous or island areas where it is difficult to open urban gas supply chains. When installing LPG supply facilities at village level and county level, it supplied consumers with 10 times higher quasi-low pressure (25 kPa to 100 kPa) than conventional gas supply pressure, increasing the risk of gas accident. Due to the pressure that is 10 times higher than the conventional gas supply pressure, large amounts of gas are released at a faster rate when leaked. In order to secure safety of quasi-low-pressure gas pipes, excess flow valves for quasi-low-pressure gas pipes are not developed and are not supplied in Korea. Therefore, Korea Gas Safety Corporation is investigating the performance standards and products of the excess flow valves in order to localize the excess flow valves.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.6
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• pp.3043-3051
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• 2013

As abnormal climate phenomena frequently happen due to the after-effect of the global warming, all nations suggest climate change response policies in many different fields to prevent global warming by reducing greenhouse gas. Especially, these days, the realization that the greenhouse gas from city buildings should be decreased is growing, and it is because that buildings are accounted for a quarter of national greenhouse gas emission and it is more than half the percentage of emissions within the city. Accordingly, Korean government sees the need to take an initiating role to fulfill low-carbon green policies and promotion strategies in the public sector, and wants to facilitate greenhouse gas reduction in the private sector as well. In this background, this study tries to examine the low-carbon planning element in public buildings and figure out the amount of carbon reduction and economic analysis centering Cheongju city as case study. Lastly, we propose some suggestion for low-carbon and greening of public buildings.

• Explosives and Blasting
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• v.38 no.4
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• pp.1-15
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• 2020

With the increase of the utilization of underground space in Korea, explosion accidents at the underground facilities such as gas pipes have occurred frequently. In urban area with high population density, individual explosion accidents are likely to spread into large complex accidents. It is necessary to investigate the effect of explosion on the stability of underground structures in urban area. In this study, a sensitivity analysis was carried out to investigate the possible influence of nearby explosion on the stability of underground structure with 8 parameters including explosion conditions and rock properties. From the sensitivity analysis using AUTODYN, the main and interaction effects of each parameters could be determined. From the analysis, it was found that the distance between explosion point and tunnel, charge weight, and Young's modulus are the most important parameters on the stress components around a tunnel.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2965-2972
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• 2011

The 21th century is carried out a rearing activity of green industries as a part of friendly echo policy for preservation of earth environment. Korean government is spreaded on a whole country to setting up a goal to a sustainable growth power of national for low carbon green growth. The recently rolling stock is received the footlights as a best friendly echo transportation of transport system of automobile, airplane, ship etc., also that is playing a big role to reduction of $CO_2$ greenhouse gas and a discharge of air pollution. This study was carried out the investigation and analysis for technology trend of the system light-weighting of a recently urban railway vehicle on commercial operating in domestic and foreign countries. As the results are proposed a short-term development technology and a long-term development technology of the system light-weighting to be developed for reduction weight of urban railway vehicle.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.77-83
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• 2002

A bacterial consortium capable of utilizing a variety of polycyclic aromatic hydrocarbons has been isolated from a former manufactured gas plant site. The consortium consisted of four members including Arthrobacter sp., Burkholderia sp., Ochrobacterium sp., and Alcaligenes sp., which were identified and characterized by the patterns of fatty acid methyl esters (FAME analysis) and carbon source utilization (BIOLOG system). With the individual members, the biodegradation characteristics of aromatic hydrocarbons depending on different growth substrates were determined. FAME analyses demonstrated that microbial fatty acid profiles changed to significant extents in response to different carbon sources, and hence, such shift profiles may be informative to characterize the biodegradation potential of a bacterium or microbial community.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.116-116
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• 2010

This paper introduces an comprehensive monitoring and management program for implementation of a real-time monitoring system that monitors condition of urban railway AC/DC transformers, disconnecting switches, circuit breakers, regulators, and GIS (Gas Insulated Switchgear). Especially, the system is applied to diagnose the overall condition of urban railway substations by sending acquired data through an OPC server to a database, effectively storing and monitoring conditions simultaneously. The above system is a management based system and is also applicable to small-scale systems.

• Journal of Environmental Impact Assessment
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• v.22 no.1
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• pp.109-116
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• 2013

By IPCC climate change scenario, the socioeconomic actions such as the land use change are closely associated with the climate change as an up zoning action of urban development to increase green gas emission to atmosphere. Prediction of the land use change with rational quality can provide better data for understanding of the climate change in future. This study aims to predict land use change of Cheongju in future and SLEUTH model is used to anticipate with the status quo condition, in which the pattern of land use change in future follows the chronical tendency of land use change during last 25 years. From 40 years prediction since 2000 year, the area urbanized compared with 2000 year increases up to 87.8% in 2040 year. The ratios of the area urbanized from agricultural area and natural area in 2040 are decreased to 53.1% and 15.3%, respectively.