• Proceedings of the KAIS Fall Conference
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• 2004.11a
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• pp.306-309
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• 2004

홍제천 유역의 비점오염원 유출부하를 분석하기 위해 강우시 하천 유량 및 수질 발생 특성, 유출고 및 유출계수 분석, 비점오염원 유출부하특성 및 원단위 산정 등에 대하여 연구하였다. 유량 및 유량가중평균농도의 경우 각 조사 시기별 강우사상에 많은 영향을 받아 크게 증가하였다가 감소하는 경향을 나타내고 있으며, 강우 1차$\~$3차 조사시기 동안 상류에서 하류로 유하 할수록 농도의 변화가 일정하지 않은 것으로 나타났다. 지점별 유출계수를 살펴보면, 구기천 및 신영천 유역 중 투수층인 산지지형이 넓게 분포되어 있어 유출계수가 낮게 산정되었으며, 구간별 배수구역 면적을 고려한 강우시 비점오염원 부하를 산정한 결과를 살펴보면 SS의 유출부하가 높게 나타나 부유물질의 주된 성분이 생물학적으로 분해 가능한 성분이기보다는 하상 퇴적물질 및 생물학적으로 난분해성 유기물질일 것으로 사료된다.

• Korean Journal of Environmental Agriculture
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• v.26 no.3
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• pp.233-238
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• 2007

To assess pollutant loads in Nakdong river from highland agriculture in Kyungbuk province we. analyzed water qualities such as BOD, COD, T-N, T-P and SS in year 2005. BOD values in rainy period (June and July) were relatively higher than those in dry period, and those in 4 sites among 17 sites ranged from 10.71-19.25 mg/L which exceeded water criteria (8 mg/L) for agricultural use. COD values showed similar trends like BOD values. These trends might be caused by outflow of nutrients applied in agricultural lands. T-N content ranged from 0.1 to 14 mg/L. Those in lower reaches of stream were greater in those in upper stream. Compared to T-N contents during non-farming season, T-N content in farming season were higher. These phenomenon could be due to continuous input of nutrients from small watercourses. Averaged T-P content in lower stream during farming season was 0.4 mg/L, which was eight times higher than the limiting level for algae occurrence (0.05 mg/L). BOD, T-P, T-N loads from alpine agricultural practices were 12.25 $kg/km^2{\cdot}day$, 0.55 $kg/km^2{\cdot}day$ and 32.35 $kg/km^2{\cdot}day$, respectively. These values were greater than those from forestry. Therefore, Best management Practices (BMP) for alpine agricultural field are needed to reduce pollutant loads in Nakdong river.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.2051-2055
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• 2008

하천의 수질오염에 영향을 주는 오염원은 점오염원과 비점오염원으로 구분된다. 비점오염원은 주로 농경지에서 강우에 따른 유출수에 의해 일어나는 반면 점오염은 생활하수, 산업폐수, 축산폐수 등에 의해 발생한다. 최근 수질오염의 특징은 과거의 대량 발생원인 점오염에 의한 수질오염에서 도시 강우 유출수나 농경지 등으로부터 발생하는 비점오염에 의한 수질오염으로 변화해 가는 경향이다. 그러나 비점오염은 점오염과 같이 일정한 출구를 통해 유출되지 않으므로 집중처리에 의한 조절 방법의 적용이 곤란하다. 본 연구에서는 공지천을 4개의 유역으로 나누어 환경부 수계오염총량관리기술지침을 이용하여 오염부하량 산정하고 원단위 오염부하를 산정하여 다음과 같은 결과를 도출하였다. 첫째, 유역내 각 계별 오염부하량의 비교와 파악이 가능하였다. 둘째, 수계오염총량관리기술지침을 기준으로 산정한 부하량은 축산계의 오염이 크게 나타났다. 공지천의 경우 도시화로 인한 오염물질의 증가에 비해 처리할 수 있는 시설이 미비한 실정으로 생태계 및 인간에게 악영향을 끼치는 것을 방지하기 위하여 공지천내 수질개선을 위한 대책마련이 시급하다. 본 연구결과를 이용하여 현재 공지천내 오염부하량을 파악하고 효율적인 수질개선을 위한 대안을 마련할수 있을 것이다.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.790-795
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• 2011

When railway crossing is required to be improved to improve road traffic efficiency, cost-benefits analysis is conducted. In the analysis, such benefits as the reduction of the delay in road vehicle traffic and related costs and reduction of traffic accidents have been appropriately estimated, however, which has not been the case for the reduction of railway operation costs and accidents. This omission may result in a significant difference in the total estimation of the benefits achievable in a long railway line where many of the crossings are improved or reconstructed. This would deteriorate the rationality of the benefit analysis. As the result, although there are various, significant benefits recognizable in the improvement of railway crossings, but they have not been included in the list of the benefits due to the difficulty in calculation. To this end, this paper proposes a methodology of the calculation of the benefits of railway crossing improvement by estimating the unit costs used in the estimation of the benefits obtainable by the reduction of the railway operation costs and the reduction of the accidents at a crossing on the basis of past studies and data.

• Journal of Animal Environmental Science
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• v.18 no.1
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• pp.19-24
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• 2012

The first objective of this study is to estimate emission coefficient of organic carbon regarding its inflow and discharge for dairy farm through reviewing domestic and foreign literature published or reported previously. Its second objective is to provide fundamental data to establish carbon cycle system related to livestock production. Based on literature review, emission coefficients by inflow of organic carbon into dairy farm were 5.9 ton C/head/year for feedstuff ingestion by milk cow, 2.3 ton C/head/year for recycling manure compost of milk cow to grassland, 318 g C/$m^2$/year for contents in grassland, 145 g C/$m^2$/year for contents in fodder crop, and 17 g C/$m^2$/year for $CO_2$ uptake by fodder crop, respectively. on the other hand, emission coefficients by discharge of organic carbon from dairy farm were 2,9 ton C/head/year for emission of $CO_2$ and $CH_4$ by respiration and burp of milk cow, 0.4 ton C/head/year for emission of $CO_2$ and $CH_4$ by decomposition of organic carbon in manure of milk cow, 440 g C/$m^2$/year for emission of $CO_2$ from grassland, and 0 for elution of organic carbon in grassland into underground water, respectively.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.2
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• pp.15-26
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• 2017

This study was conducted to investigate and analyze the discharge characteristics of recyclable material from S-city, S-district, in order to improve the sorting efficiency in recycling sorting facility. The characteristics of recyclable materials collected were analyzed in three different scopes; source origin, collection and transportation, and sorting steps. The average of recyclable waste generation is $0.121kg/day^*man$. Regional collection period appears to be three times a week, and the density of mixed recyclable wastes showed the average of $202.4kg/m^3$ in the waste collection vehicle. In the analysis into the sorting steps, the average of carrying amount of mixed recycling products is 1,154.6 ton/month, the average of appeared density is $181kg/m^3$, the average amount of separated recycling products is 448.5kg/month, and the density of recycling residue is found out to be $48kg/m^3$. The sorting rate of recyclable material is 38.85% and the percentage of residues is 55.90%. Out of 7,744.8 tons of the total recyclable residues, 4,272.1 tons were found out to be possible recylable materials. As a result of increasing the recycling rate of residues, the encouragement of base-recycling, the automation and retrofit of sorting equipment, and energy recovery from recycling residue were discussed.

• Korean Journal of Environmental Agriculture
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• v.27 no.1
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• pp.44-49
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• 2008

The purpose of this study is to investigate the current status, including the maintenance problems and removal efficiency, of small sewage treatment facilities in Chung-nam province(Asan, Buyeo, and Gongju city). Our results showed that inflow water quality of Asan city was 19.1 mg/L of BOD, 29.0 mg/L of COD, 13.4 mg/L of T-N and 1.5 mg/L of T-P, respectively, which was much higher than any other site. Among the factors known to be an important index of water quality, the SS and BOD removal efficiency was about 70% and 50% respectively. However, the nitrogen removal efficiency was less than 10%. The total removal efficiency of pollutant was 71.1% of SS, 52.6% of BOD, 46.2% of COD, 9.2% of T-P and 4.6% of T-N respectively. Therefore nitrogen removal processes are required to prevent serious eutrophication of small river. Removal efficiency for BOD and SS of high-efficient sewage treatment facilities (STFs) and contact oxidation process was much higher than another process. Performance of these sewage treatment facilities(STFs) is not optimal due to ineffective planning for the inflow water quality. To improve these facilities, it is proposed that a technical expert analysis of water quality at these facilities is periodically required.

• Journal of the Society of Disaster Information
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• v.4 no.1
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• pp.86-100
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• 2008

It is needed to classify the kinds of construction and demolition(c&d) debris to 6 catagories of waste concrete, waste asphalt concrete, waste wood, scraps, combustible waste and incombustible waste in order to properly do a separate discharge and to estimate unit generation rate in construction site. Also, in this case, the unit treating cost for mixed wastes should be applied with the unit treating cost for combustible waste. The construction standard materials estimation data is used for basic data for estimating unit generation rate. The mixed wastes in this data should be classified to waste wood, combustible waste and incombustible waste, and their ratio is obtained by using the unit generation rate of Asia Pacific Environment and Management Institute and Seoul Metropolitan Development Institute. The waste amounts generated from newly-built construction can be obtained from multiplying the loss rate by the amount of materials used from construction standard estimation data. Also, those from dismantling construction can be obtained by subtracting waste amount generated during newly-built construction from total input amount of materials in newly-built construction. Those in two cases can be used in construction site. It can be used for estimating the amount generated and establishing the treating plan in the case of setting up the policy of waste management and doing the environment impact assessment.

• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.4
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• pp.123-130
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• 2022

This study was conducted to prepare a plan for the operation and improvement of excretory treatment facilities in Seoul, where the amount of excrement is expected to continue to increase due to the increase in the installation of septic tanks, a private sewage treatment facility. As a result, there are problems due to the lack of treatment capacity and increase in the amount brought in. To improve this, it is necessary to expand the overall excretory treatment facility, adjust the area of some facilities, reduce the amount of excrement through the realization of excretory units, and reduce the amount of excrement due to the change of the type of sewage treatment facility.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.743-746
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• 2007

Now, in a domestic country, the rebuilding and redevelopment of existing houses has been rapidly increasing with an economic growth and the improvement of living condition. The percentage of C&D waste among generating waste in domestic is more and more increasing. Accordingly, Our government or company are doing much effort to decrease the C&D waste. But now, we can not find any results about system development for estimating and managing rightly the C&D waste quantity. Now, much social cost are increasing for reason of the institutional inertia for forecasting quantity of C&D waste. Therefore, This study suggest some methods be able to estimate it of apartment easily. The methods are composed with utilization of a basic unit, a CAD drawing and a 3D object. Each module can be also used individually according to the purpose of a user.