• Proceedings of the KSRS Conference
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• v.2
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• pp.559-562
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• 2006

Although flood is a very common natural disaster in Bangladesh, recently Dhaka, the capital city of Bangladesh got flooded even in moderate rainfall. Accordingly, on January 2002 the sale and use of polythene bags were banned, by identifying it as one of the main causes for such flooding. Now the question arises, whether only polythene shopping bags are alone responsible for causing water logging problem. Accordingly, the objective of this study is to detect the reason(s) for the recent prolonged water logging problem in Dhaka City, even by small amount of rainfall. Both contingent valuation method and remote sensing technique were used for comparison of the results. The results of the study indicated that, not only polythene bags, but also unplanned land filling is also liable for creating water logging problem in Dhaka City. Finally, the study suggested that, the value of wetlands lost, which is directly related to the recent water logging problem, is more higher than what actually thought by the citizens of Dhaka City.

• Journal of Life Science
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• v.19 no.3
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• pp.373-377
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• 2009

Poliovirus, coxsackievirus, and ecovirus isolates from environmental sources were compared with laboratory strains to determine their removal rate in the water treatment process. The recovery efficiencies of poliovirus, coxsackievirus and echovirus using positive strains ranged from $72{\sim}108%$. Regarding virus removal efficiency in water treatment of pilot-plants, about 99% of all of the viruses were removed in the sedimentation step and 100% of viruses were clearly removed through post-ozonation and BAC filteration. Using six cell lines tested viral sensitivity in cell line and showed different sensitivity as viruses. Polioviruses showed higher sensitivity in the BGMK cell line than other cells, and coxsackieviruses were detected in higher level in the BGMK and Vero cell lines. On the other hand, the RD cell line was useful in the isolation of ecoviruses.

• Journal of Environmental Science International
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• v.25 no.10
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• pp.1381-1387
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• 2016

This study aims to establish baseline data for sustainable monitoring by applying the green city index (GCI), which is set up to evaluate the city level, to the city of Gangneung-si, which was designated as a pilot city for the Low-carbon Green Growth City project by the Ministry of Land, Infrastructure, and Transportation. The GCI was applied in the framework of European systems, while considering the social and economic status of Korea. Indicators from 7 areas-$CO_2$, energy, building, transportation, water, waste, and quality of atmosphere were analyzed, except for qualitative indicators. Results indicate that total $CO_2$ emissions were 30.8 tons per capita, or 2.2 tons per one million units of real GDP. The total final energy consumption was 0.231 TOE/capita, or 0.317 TOE per one million units of real GDP. The percentage of total energy derived from renewable resources was 0.41% and energy consumption by the building was $433.5Mwh/1,000m^2$. The total percentage of the working population travelling to work daily by public transportation (limited to bus) was 19%. Further, the total annual water consumption was $99m^3/capita$, and the water lost in the water distribution system was $0.057m^3/capita/day$. The total annual waste collected was 0.0077 ton per capita, The annual mean emission were 0.014 ppm/day for $NO_2$, 0.005 ppm/day for $SO_2$, and 0.019 ppm/day for $O_3$. The annual mean for PM10 emissions was $39{\mu}g/m^3/day$.

• KIEAE Journal
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• v.2 no.3
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• pp.25-32
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• 2002

The demand for water in a city area has enormously increased due to the concentration of population and improvement of the living quality. In this reason, the water shortage and the pollution by city sewage seem to be inevitable. For saving city water and meeting the demands from the city, the wastewater recycling system can be used, which makes used water reusable by a certain purification process. In Korea, the application of a wastewater recycling system to the buildings has continuously been adopted since its first appearance at the Lotte World Complex in 1989. However, the system has not been in fashion because of its high cost and users' negative attitude against recycled water. A research based on literature review and a case study for a recycling water system was carried out and an estimation and evaluation model was proposed. The results from the present study suggest that the optimal size of the recycling water system should be designed within 30-40% of total water demand in a building. Also, it was found that economic benefits could be expected within the payback period of 5.3 years by securing the operation rate over 70%.

• Journal of Environmental Science International
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• v.19 no.11
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• pp.1375-1384
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• 2010

Growth in population and urbanization has progressively increased the loading of pollutants from nonpoint sources as well as point sources. Especially in case of road regions such as city trunk road, national road and highway are rainfall and pollutants runoff intensive landuses since they are impervious and emit a lot of pollutants from vehicle activity. This research was conducted to investigate the nonpoint sources concentration and quantifying stormwater pollutants which are contained in rainfall runoff water. Three different monitoring sites in Jinju and Changwon city were equipped with an automatic rainfall gauge and flow meter for measuring rainfall and the volume of rainfall runoff. In the case of average EMC value, city trunk road was shown the highest value in target water quality items like as BOD, COD, SS, TN and TP. Or the amount of runoff loads by water quality items showed the highest value in city trunk road. And runoff load in city trunk road was 43.8 times high value compared to highway by value of city trunk road $356.7 mg/m^2$, highway $8.150 mg/m^2$, national road $19.99 mg/m^2$ in the case of BOD.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2002.10a
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• pp.79-82
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• 2002

To study the effect of functional water on the compressive strength of mortar, city water was changed to functional water through ceramics treatment. The change of characteristics of water was measured with $O^{17}$ NMR and Killian Camera. The compressive strength of mortar was measured with various curing conditions. The test results show that by the ceramics treatment the characteristics of city water was changed. At 28 days under curing condition, the compressive strength of mortar which was mix-proportioned with treated water was increased about 22 % than that of mortar which was mix-proportioned with untreated city water.

• Journal of Life Science
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• v.22 no.9
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• pp.1237-1242
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• 2012

The use of biological-activated carbon (BAC) processes in water treatment involves biofiltration, which maximizes the bacteria's capabilities to remove organic matter. In this study, the distribution of the bacterial community was assessed in response to different types of BAC processes applied downstream in the Nakdong River. The bacterial biomass and activity were $1.20{\sim}34.0{\times}10^7$ CFU/g and 0.61~1.10 mg-C/$m^3{\cdot}hr$ in coal-based BAC, respectively. The attachment of the bacterial biomass and the removal efficiency of the organic carbon were greatest with the coal-based activated carbon. The bacteria attached to each activated carbon material were detected in the order of Pseudomonas genus, Chryseomonas genus, Flavobacterium genus, Alcaligenes genus, Acinetobacter genus, and Spingomona genus. Pseudomonas cepacia was the dominant species in the coal-based materials, and Chryseomonas luteola was the dominant species in the wood-based material.

• Journal of Environmental Science International
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• v.15 no.10
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• pp.935-943
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• 2006

This study focuses on analyzing the inflow characteristic of contaminants of city water that flows into a main water system like a reservoir, and intends to provide basic data which can be efficiently reflected on water quality management policy and decision making of a reservoir. The conclusion obtained from the analysis of the inflow of a main water system by analyzing the inflow property of city water contaminants is as follows. In the case of Chungju-cheon stream which is the city water, pollution load from the basic outflow is low when it rains, and with high load of basic outflow during the dry season, due to the discharge of pollutants from the city, the quality of water becomes worse. In the case of Chungju-cheon stream, average BOD is $4.53mg/{\ell}$ when it rains, and the contaminants increase and flow in about 7.8% compared to the average BOD during the average droughty season. The average SS concentration in water is $798.67mg/{\ell}$ and increased 97.2% compared to the average droughty season.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.183-183
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• 2023

Smart water cities (SWC) are urban municipalities that utilizes modern innovations in managing and preserving the urban water cycle in the city; with the purpose of securing sustainability and improving the quality of life of the urban population. Understanding the different urban water characteristics and management strategies of cities situate a baseline in the development of evaluation scheme in determining whether the city is smart and sustainable. This research herein aims to develop measurements and evaluation for SWC Key Performance Indicators (KPIs), and set up a unified global standard and certification scheme. The assessment for SWC is performed in technical, as well as governance and prospective aspects. KPI measurements under Technical Pillar assess the cities' use of technologies in providing sufficient water supply, monitoring water quality, strengthening disaster resilience, minimizing hazard vulnerability, and maintaining and protecting the urban water ecosystem. Governance and Prospective Pillar on the other hand, evaluates the social, economic and administrative systems set in place to manage the water resources, delivering water services to different levels of society. The performance assessment is composed of a variety of procedures performed in a quantitative and qualitative manner, such as computations through established equations, interviews with authorities in charge, field survey inspections, etc. The developed SWC KPI measurements are used to evaluate the urban water management practices for Busan Eco Delta city, a Semulmeori waterfront area in Gangseo district, Busan. The evaluation and scoring process was presented and established, serving as the basis for the application of the smart water city certification all over the world. The established guideline will be used to analyze future cities, providing integrated and comprehensive information on the status of their urban water cycle, gathering new techniques and proposing solutions for smarter measures.

• Journal of architectural history
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• v.28 no.6
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• pp.55-65
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• 2019

Ganggyeong, a city which is located at riverside of Geum River, played a role to connect the inland cities and the coastal cities through the Geum river waterway. In Chosun dynasty, Ganggyeong was one of the three major markets in Korea, and at the same time, it was one of the two river docks in Korea. However, after the railway was installed in Korea, railroad was more important than waterway in transporting logistics and in 1911 Honam railroad and Ganggyeong railway station was installed. Thus it was necessary to reorganize urban structure of Ganggyeong city from the traditional river-dock city to modern railroad city. In addition, urban infrastructure to prevent flood damage was needed because Ganggyeong suffered from floods and water shortages every year. Therefore, between 1910s and 1930s large-scale social infrastructures including road, water and sewage system, river bank, floodgate was constructed not only to revitalize the declining city but also to prevent flood damage and water shortages that hinder urban development. The installation of urban infrastructure has enabled the urban expansion and development of Ganggyeong city, and it is still served as a basic urban structure.