• Environmental Engineering Research
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• 제18권2호
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• pp.85-90
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• 2013

This study is an attempt to quantify rainwater utilization and miscellaneous water demand in Tokyo's 23 special wards, the core of the urban area in Tokyo, Japan, in order to elucidate the potential of further rainwater utilization. The rainwater utilization for miscellaneous appropriate water demands, including toilet flushing, air conditioning, and garden irrigation, were calculated for six different types of building: residential house, office, department store, supermarket, restaurant, and accommodation. Miscellaneous water demands in these different types of building were expressed in terms of equivalent rainfall of 767, 1,133, 3,318, 1,887, 16,574, and 2,227 (mm/yr), respectively, compared with 1,528 mm of Tokyo's average annual precipitation. Building types, numbers and its height were considered in this study area using geographic information system data to quantify miscellaneous water demands and the amount of rainwater utilization in each ward. Area precipitation-demand ratio was used to measure rainwater utilization potential for miscellaneous water demands. Office and commercial areas, such as Chiyoda ward, showed rainwater utilization potentials of <0.3, which was relatively low compared to those wards where many residential houses are located. This is attributed to the relatively high miscellaneous water demand. In light of rainwater utilization based on building level, the introduction of rainwater storage mechanisms with a storage depth of 50 mm for six different types of buildings was considered, and calculated as rainfall of 573, 679, 819, 766, 930, and 787 (mm), respectively. Total rainwater utilization using such storage facilities in each building from 23 wards resulted in the retention of 102,760,000 $m^3$ of water for use in miscellaneous applications annually, and this volume corresponded to 26.3% of annual miscellaneous water demand.

• 한국수자원학회논문집
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• 제39권12호
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• pp.1057-1066
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• 2006

용수는 인간의 생존과 산업생산에 있어서 필수적인 투입요소이다. 용수공급을 위해서는 많은 비용이 소요되지만 경제적 편익도 발생하며, 이에 대한 정보는 용수공급사업의 평가에서 중요하게 활용된다. 이에 본 연구에서는 서울시 가정용수 공급으로 인해 발생하는 경제적 편익을 추정하고자 한다. 특히 2001년부터 2004년까지의 기간을 대상으로 하여, 서울시 11개 수도사업소별로 연도별 소비자 잉여 및 경제적 가치를 추정한다. 소비자 잉여의 계산 과정에서 필요한 가격탄력성에 대한 정보는 서울시 가정용수 수요함수를 직접 추정하여 구했으며, 소비자 잉여의 계산은 최근에 개발된 산식을 이용한다. 서울시 가정용수 수요의 가격탄력성은 -0.810 및 -1.011이였으며, 이를 이용하여 계산된 소비자 잉여와 경제적 가치는 2003년의 경우 각각 1,319억원에서 1,646억원 및 3,986억원에서 4,313억원에 달한다.

• 설비공학논문집
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• 제19권12호
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• pp.857-864
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• 2007

In the current residential building, hot water supply system consumes the second largest energy in order to make the thermal comport condition of residential space. The more residential environment improves the more the demand for hot water and water consumption is increasing gradually. So this study examines the possibility of applying the recirculation for individual hot water supply system compared with the existing method for waiting time for hot water, wasted water and energy consumption. The results are as follows. (1) In case of recirculation system method the waiting time for hot water can be reduced up to $69\sim85%$ in spring and fall period and so dose up to $77\sim85%$ in winter period. (2) The total wasted water has a little change compared with the existing method which can make the total wasted water reduced about $77\sim86%$. (3) The efficiency of hot water supply system can be improved, if the method which blocks the inflow of cold water is applied, when return pump is operated to recirculate hot water in recirculation system.

• 자원ㆍ환경경제연구
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• 제16권4호
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• pp.781-802
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• 2007

본 연구는 스톤-게리(Stone-Geary) 모형을 이용하여 서울시 가정용 생활용수의 수요를 추정하고 이에 근거하여 물 수요의 가격탄력성과 소득탄력성을 추정한다. 분석결과, 서울시 전체 가정용 물 소비량 중 기초소비가 차지하는 비중이 평균 84%로 나타났다. 가정에서 사용하는 월평균 물 소비량이 최근에는 $16{\sim}20m^3$ 이하인 점을 감안하면, 가격을 통한 실질적인 물 수요관리 효과를 도모하기 위해서는 구간요금체계의 최저 수준을 현재의 월 $30m^3$에서 월 $15m^3$ 정도로 축소 조정할 필요가 있다는 점을 발견하였다.

• 한국주거학회논문집
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• 제24권5호
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• pp.1-8
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• 2013

Recently, as people have more interest in health, and some change takes place in their lifestyles, a demand for environment-friendly residential space is also increasing. Research on the introduction of natural elements is mostly conducted for humans to pursue a more pleasant and comfortable life in residential space since it has one of the closest relation with humans. Therefore, it is such an important assignment at present when environmental problems are considered significant. Based on such a necessity, this study analyzed the introduction types and characteristics of natural elements in residential space by considering essential and psychological aspects more than previous researches on residential space with practical and functional aspects. As natural elements, this study put limits on plants and water that are used a lot in the interior space, and by dividing introduction types into recomposition of courtyard space, spatial partition and decorative elements, this study carried out a case analysis of residential space structures recently completed in Japan. As a basic research on space planning that is desperately required by change in the residential life paradigm and on the basis of understanding about nature, it is expected that the results of this study will be used as design basic data useful when establishing plans of introducing natural elements for residential space in the future.

• 자원ㆍ환경경제연구
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• 제9권2호
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• pp.311-332
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• 2000

The main aim of this paper is to estimate the change in the quantity demanded of public water when the economic factors such as income and water price are changed. The privious methods to estimate the quantity of public water demanded has been usually based on the LPCD(liter per capita per day). Implicitly, this method regards the price of water as given. If the water price and income elasticities of water demand are estimated using the time-series and pooled data analysis. In the second step, the quantity demanded of public water are forecasted using the estimated elasticities. The results show that we can reduce the quantity demanded of residential water considerably when the water price is changed.

• 대한화학회지
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• 제14권1호
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• pp.5-12
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• 1970

River water and industrial waste water in Seoul were studied by means of chemical oxygen demand(COD) as an indicator for water pollution, from August 1967 to July 1968. Rivers flowing through residential and industrial areas are badly contaminated and COD of water in Han River increases as it progresses to downstream. Seasonal variation of COD showed that higher value of COD was observed in spring and lower in autumn. It is clear that the seasonal variation of COD is influenced by the precipitation. Close relationship was found between COD and population density. The lowest COD curve obtained by plotting COD values against population density and show that the curve slopes upward. The discontinuation of the curve was shown at the population density of 14,000/km$^2$; an increase in COD was acute over the population density of 14,000/km$^2$.

• 한국농공학회지
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• 제45권7호
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• pp.1-10
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• 2003

In order to analyze the water supply capacity in an estuary reservoir, a system composed of daily water balance model and daily inflow model was developed. The agricultural water demands to paddy fields, domestic water demands to residential areas, and industrial water demands to industrial complexes were considered in this daily water balance model. Likewise, the outflow volume through sluice gates and inside the water level at the start of the outflow was initially conditioned to simulate estuary reservoir storage. The DAWAST model (Noh, 1991) was selected to simulate daily estuary reservoir inflow, wherein return flows from agricultural, domestic, and industrial water were included to simulate runoff. Using this system, the water supply capacity in the Geum River estuary reservoir was analyzed.

• 설비공학논문집
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• 제20권6호
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• pp.394-399
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• 2008

There are many attempts to use a fuel cell system as a residential power generation system. The purpose of this study is to investigate the optimal design of a water tank for a hot water system when the fuel cell co-generation system is combined with a domestic hot water supply system. The demands of hot water supply per month per home are investigated in Busan for a year. It showed somewhat large differences between the actual demand and the designed demand of hot water, but the actual capacity of hourly averaged hot water demands is analyzed as $60{\ell}/h$ in this study based on the actual demand. The experiments are performed in the various inlet and outlet locations of nozzles, and the hot water consumption rates. The experimental results are showed that the optimal capacity of the water tank is $200{\ell}$ when the thermal efficiency, the storing capacity of hot water and the space for installation are considered.

• 한국태양에너지학회 논문집
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• 제38권6호
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• pp.37-49
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• 2018

In this paper a new kind of unit-prefabricated building is shown. The unit-prefabricated buildings are made up living unit, energy unit, water unit. The design trend implemented the energy insulation, solar PV panels, energy storage system which are maintained for zero energy buildings. We made a prototype for zero energy flexible residential unit. The first step, we was evaluated the physical performance, insulation, airtightness. The second step, we was evaluated energy performance building to design heating and cooling system to combined PV system. As a results, the insulation performance wall was $0.18W/(m^2{\cdot}K)$. The results of air-tightness was 12.13 ACH@50 (1/h). The building energy demand ratings and solar energy generation has the possible to be ballanced.