• 상하수도학회지
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• 제20권4호
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• pp.509-518
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• 2006

Although final water of domestic water treatment plants almost contains highly corrosive characteristics, the countermeasures for eliminating internal corrosion of pipeline system have not been conducted yet by controlling water quality in plants. The technologies of internal corrosion control are to control water quality parameters(pH, Alkalinity, and Calcium Hardness etc.) and to use corrosion inhibitor. Under the conditions of domestic water treatment, first of all, the technologies of adjusting water quality parameters has to be considered. Otherwise, The technology of using corrosion inhibitor is favorably thought to be applied with the technology of adjusting water quality parameters in accordance with the result of availability for water treatment process. Since the technology of adjusting water quality parameter influences on other water treatment processes, the guideline of water quality management to be apt for water quality characteristic is required to be estabilished. While the selection of proper chemicals and technologies is dependent upon the raw water characteristics and water treatment process, typically, the technology of $Ca(OH)_2$ & $CO_2$ additions is considered more effective than other technologies in order to adjust pH and Alkalinity, increase $Ca^{2+}$ and form $CaCO_3$ film

• 상하수도학회지
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• 제36권5호
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• pp.289-296
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• 2022

Mangyeong River and Dongjin River are highly dependent on external regions for domestic and agricultural water, and the agricultural water supply and use system of those rivers are very complicated. For smooth water supply, rivers are used as a supply system. Of the total river water use permits (as of 2019), agricultural water accounts for 97.5%, 80.4% in Mangyeong River and Dongjin River, respectively. The excessive intake of river water as agricultural purpose is causing the stream to dry out and to deteriorate the ecological health of the river. It is necessary to minimize the water use system that takes in and utilizes river water. In both rivers, the flow rate of agricultural drainage and the load of major water quality items that flowing into the main stream are similar to or higher than those of the major tributaries, indicating that management is necessary to improve the water quality of the river. It is necessary to understand the effect of agricultural drainage on river water quality by establishing a continuous monitoring system for the form of agricultural drainage.

• 상하수도학회지
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• 제25권3호
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• pp.325-334
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• 2011

Market Environment around water work industry is rapidly changing. ISO, International Organization for Standardization, announced the international water work service standard for comparison and evaluation between nations and businesses. And developed countries in water work are introducing market principle for growth of nation's water industry and reinforcement of its competitiveness. Also, some local governments entrusted their water utilities for improvement of competitiveness of water work. However, as some failure cases from overseas came out with emphasis, there are many refuting perspective about entrusted operation achievements of domestic water market. Hence, this paper evaluated competitiveness of domestic local water utilities from the perspective of productivity. After evaluating productivity using Malmquist productivity index, the authors compared and analyzed whether there is a difference of productivity between two different operating types by using Mann-Whitney test. As a result of analysis, it has shown that local water utilities achieved higher productivity at entrusted operation type rather than direct operation type. The local water utilities which chose entrusted operation had increased the productivity 13.9% on total factor productivity(TFP) during experimenting period, while the local water utilities which chose direct operation had increased 0.2%. The background of achieving this high productivity in entrusted operation was analyzed as a result of the higher technological effectiveness of a special water company. The result of this study can be referred when local government needs to decide on what operating types they will use.

• 한국실내디자인학회논문집
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• 제25권4호
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• pp.3-12
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• 2016

The purpose of this study was to analyze City squares in Europe according to Biophilic Design elements to apply domestic Indoor Squares in Mixed-use building for relaxation. This study seeks to present a direction for designing an indoor square that uses the aspects of European city square. The following details consist the purpose of the study. First, Perspective from the Biophilic design and analyzing criteria of Europe city square. Second, European city square is analyzed to establish the criteria to be applied to indoor square. Third, based on European city square analysis, the planning direction for domestic indoor square is suggested. This result of paper proceeds as follows. First, it describes the analysis of the Indoor Squares of the domestic Mixed-use building. The results were derived of the fact that not applying the water elements and Facade greening. Second, In Europe Square, It is accounted for the highest proportion (33%) of the spaciousness. Third, Through a comparative analysis domestic indoor square was derived that the higher the need to improve the spaciousness and botanical motif. It is the ultimate goal of this study based on the analysis of the city square to set the criteria for the biophilic design of the indoor square to present the orientation of the indoor square.

• 한국수자원학회논문집
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• 제34권6호
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• pp.587-596
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• 2001

본 연구는 우수를 생활용수로 활용하고 있는 도서지역의 재래적인 우수이용방법을 개선하고 안정적으로 생활용수를 공급할 수 있는 우수이용 시스템을 개발하는데 연구의 목적이 있다. 이를 위하여 연구의 대상지역으로는 제주도 지역을 선정하고 실제 강우 및 생활용수의 관계를 run이론을 이용하여 규명하고 그 결과는 우수이용 시스템의 집수면적과 탱크크기를 설계하는 기법을 제시하였다. 실제에 적용해 본 결과, 설계된 우수이용 시스템이 제주도지역에서 안정적으로 운영이 되는 것으로 나타났으며, 이는 제주도뿐만 아니라 다른 도서지역에서도 본 시스템의 적용이 가능한 것으로 판단되었다. 따라서 본 시스템을 도서 지역의 지붕개량사업과 연계시켜 시행할 때, 도서지역의 주거환경개선과 용수확보를 병행할 수 있는 효과가 기대된다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.350-355
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• 2009

Air-conditioning system by ocean thermal energy has been developed in the areas of Europe, North America and Japan because there are abundant amount of thermal energy potential in the ocean and permanent free use for the thermal energy using the air-conditioning system. In the case of domestic ocean thermal energy resource, ocean thermal energy potential exists about 27,155Tcal/year and totally 20,285Tcal/year of possible thermal energy use by heat pump, which are reported from the survey of the 7 domestic near shore cities. Present study is aimed to survey the current development status of domestic and overseas air-conditioning system by ocean thermal energy, especially, for the air-conditioning facility technologies using sea water.

• 상하수도학회지
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• 제24권5호
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• pp.495-508
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• 2010

The aim of this study is to develop a quantified water loss Index to evaluate and manage leakage scientifically for the reduction of non-revenue water in water distribution systems. For the purpose, unavoidable background leakage suggested from UK water industry and IWA, and allowable water leakage in accord with the concept of allowable water loss are proposed by analyzing the inflow into two study water districts and the short-term water use of each customer in the districts. The study distribution areas are selected among the metered districts with good maintenance of leakage after improvement activities in Nonsan, medium sized city in Korea. Estimation models of allowable leakage are developed by metering and analyzing the minimum night flow at residential and commercial areas in the city. In the results of the investigation, it is estimated that background night flow in residential area was larger than that of commercial area where the types of business shows small water use characteristics. Meanwhile, night flow and background water loss on internal plumbing systems show great differences for each district which is influenced much by the water use characteristics and facilities scale. Based on metering water use data in various districts, leakage management criteria can be established under the consideration of domestic conditions in Korea by analyzing separated real water use and background leakage and it is possible to apply into presentation of optimal leakage level and reasonable time for working activities for leakage reduction.

• 한국물환경학회지
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• 제27권2호
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• pp.178-187
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• 2011

National water supply, water resources available, the ratio of water supply to total water resources, and the ratio of water supply to available water resources were investigated to find global seawater desalination plant market for 163 nations. Water resources available per capita from 2007 to 2016, population in water scarcity region from 2011 to 2016, and the ratio of water scarcity population to total population were also analyzed for the countries. Annual percentage increase in total municipal drinking water capital expenditure and Annual percentage increase in total industrial water market were analyzed to predict the amount of water supply by use. 76 countries are suffering from water scarcity and 60 countries among the countries have coastal regions. Forty countries were selected by considering the considerable amount and highly increasing trend of water demand by use. Most countries show increasing trend of industrial water and 82 countries have more than 4% annual increasing rate for domestic water expense from 2008 to 2016 among 163 countries. Among the 76 water scarcity countries 16 countries were finally selected by considering expense prediction by use. Middle-east, east asia, pacific ocean, and west europe regions include most selected countries.

• 한국표면공학회지
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• 제9권3호
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• pp.5-8
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• 1976

In this study, a ruture strength of epoxy resin film coated on the leaking spot in waterpipe line was determined, using water pressure, without interrupting water supply. This results could be used for the sealing of water leakage in large size waterpipe lines. An experimental equation {{{{P=Kt^m~ /R^n~ (m=2, n=3.5) }} was also obtained, where P is the rupture pressure, K is constant, t is the thickness and R is the radius of the resin film. From this results, the safe쇼 thickness of the film for a domestic use was calculated with various radii against the maximum pressure.

• 대한건축학회논문집:구조계
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• 제34권7호
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• pp.43-52
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• 2018

In this study, annual site and primary energy use intensities (EUIs) and CO2 emission intensities (CEIs) per area by end use were estimated based on the measurement data from June 2016 to May 2017 of 50 sample apartment units in Seoul. In addition, estimated site EUIs by end use were compared to the U.S. Residential Energy Consumption Survey (RECS) 2009 data. Site EUIs by end use were found to be in the order of heating > electric appliance > domestic hot water > cooking > lighting > cooling > air movement. In the case of primary EUIs and CEIs by end use, electric appliance was found to be the largest. As results of comparison with the RECS 2009 data, it was found that site EUIs were very similar for heating, domestic hot water and electric appliance, etc., but slightly different for cooling. The number of sample apartment units will continue to increase until 2020 (total number of samples 200) and intensities data by end use will be continuously updated through continuous collection of measurement data.