• 한국물환경학회지
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• 제23권4호
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• pp.490-497
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• 2007

A Combined sewer overflows (CSOs) are themselves a significant source of water pollution. Therefore, the control of urban drainage for CSOs reduction and receiving water quality protection is needed. Examples in combined sewer systems include downstream storage facilities that detain runoff during periods of high flow and allow the detained water to be conveyed by an interceptor sewer to a centralized treatment plant during periods of low flow. The design of such facilities as stormwater detention storage is highly dependant on the temporal variability of storage capacity available (which is influenced by the duration of interevent dry periods) as well as the infiltration capacity of soil and recovery of depression storage. As a result, a continuous approach is required to adequately size such facilities. This study for the continuous long-term analysis of urban drainage system used analytical probabilistic model based on derived probability distribution theory. As an alternative to the modeling of urban drainage system for planning or screening level analysis of runoff control alternatives, this model have evolved that offer much ease and flexibility in terms of computation while considering long-term meteorology. This study presented rainfall and runoff characteristics of the subject area using analytical probabilistic model. This study presented the average annual COSs and number of COSs when the interceptor capacity is in the range $3{\times}DWF$ (dry weather flow). Also, calculated the average annual mass of pollutant lost in CSOs using Event Mean Concentration. Finally, this study presented a decision of storage volume for CSOs reduction and water quality protection.

• 한국물환경학회지
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• 제30권6호
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• pp.605-611
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• 2014

This research was carried out to examine the concentration and fate of dissolved organic matter due to the increased detention time in middle and down stream of the Nakdong River. Aldo the characteristics of biodegradation of DOM were investigated according to the various water sources. The approaches used to characterize DOM biodegradability include the changes in DOC concentration and DOM fraction. Long-term biodegradation test for each organic source was also conducted. As the result, maximum 50% of DOC was reduced during the first 30 days of biodegradation tests. After 30 days, biodegradation of organic matter was continuously progressed, as showing continuous reduction of DOC. While DOC concentration was reduced, SUVA values for the organic matters were increased. Properties of dissolved organic matter by water sources also showed decreasing hydrophilic components while showing increased hydrophobic components. The more rapid reduction of the hydrophilic components than hydrophobic components might be due to the preferential degradation of the hydrophilic components by microorganisms during biodegradation process.

• Asian-Australasian Journal of Animal Sciences
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• 제9권6호
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• pp.615-635
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• 1996

The animal industry must be environmentally sound to ensure its long-term sustainable growth. Livestock wastes mostly manure, can be a valuable resource as well as a potential hazard to environment. The first option of manure management is developing an 'environmentally sound' feeding program and feeds so there are less excreted nutrients that need to be managed. Once the manure is produced it can be best utilized as a fertilizer of a soil conditioner. In many countries the amount of manure that can be spread on land depends on the nutrient requirements of the crop being grown. The laws specify maximum application rates and not animal stocking rates. Farmer who reduce the N and P component of manure can release pressure on the environment without having to reduce the number of animals. There are alternative system for housing and manure treatment which generate manure that are easier to handle and have less pollutants or more economic value. Treated animal waste may also be used as a feedstuff or fuel source. Most of the options of waste management result in increased costs to implement. It is necessary to assess the economics in order to find an acceptable compromise between the increased costs and the benefit to the environment. Animal welfare is also becoming more and more of an issue and it will lead to systems where animals are kept in less confined environment. The new system will have a great impact in the waste management system in the future.

• 한국환경농학회지
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• 제31권4호
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• pp.328-343
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• 2012

BACKGROUND: For effective subwatershed management, it is very important to select the tributaries for improving water quality and understand the characteristics of tributaries. Until now, however, the case study of main streams has been managed. 17 tributaries in Geum river subwatershed were monitored to regulate the source of water contaminations and identify their current situations in this study. METHODS AND RESULTS: As pollution indicators, such as biological oxygen demand($BOD_5$), chemical oxygen demand($COD_{Mn}$), suspended solid(SS), total nitrogen (T-N), total phosphate(T-P) and total organic carbon(TOC) in Geum river were examined from January to December in 2011. The results were as follows : The annual average concentration of nutrients in Yongdam reservoir upsteam was 0.7 mg/L for BOD, 3.0 mg/L for COD, 8.4 mg/L for SS, 2.905 mg/L for T-N, 0.035 mg/L for T-P and 1.6 mg/L for TOC. Water quality of Daechung reservoir upstream was mostly similar tendency in comparison to Yongdam reservoir upstream. Among the 22 tributaries, water quality in Daechung reservoir downstream was more polluted. T-N contents were significantly high in Miho B4 located Daechung reservoir downstream(annual average concentration: 13.53 mg/L). In cases of Miho A1, A2 and C1, pollution degree was worsened during rainy season expecially. CONCLUSION(S): For improving water quality of Geum river subwatershed, the tributaries in the Mihocheon area should be preferentially considered. Mihocheon tributary is the highest in pollution site, and thus a study on long-term effects should be research.

• 한국물환경학회지
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• 제28권5호
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• pp.663-668
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• 2012

The feasibility of enhancing biological nutrient removal from an industrial wastewater was tested with food waste leachate and sugar liquid waste as external carbon sources. Long term influences of adding external carbon sources were investigated to see how the biological nutrient removal process worked in terms of the removal efficiency. The addition of the external carbons led to a significant improvement in the removal efficiency of nutrients: from 49% to approximately 76% for nitrogen and from 64% to around 80% for phosphorus. Approximately, 20% of the removal nitrogen was synthesized into biomass, while the remaining 80% was denitrified. Though the addition of external carbon sources improved nutrient removal, it also increased the waste sludge production substantially. The optimal observed BOD/TN ratio, based on nitrogen removal and sludge production, was around 4.0 in this study.

• 대한지리학회지
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• 제33권spc호
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• pp.677-684
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• 1998

'문화'라는 용어는 생활양식(그림 1), 해석체계(그림 2), 제 4의 구조(그림 3), 세련된 취향(그림 4), 지식과 예술의 상부구조(그림 5), 생물학적 지지 구조(그림 6), 도는 인간의 모든 조건들(그림 7) 등으로 정의될 수 있다. 문화라는 용어를 어떻게 정의하든 각각의 정의에는 이와 연관된 '환'에 대한 정의가 전제되어 있다. 어떠한 정의를 채택하는가 하는 것은 각각의 정의를 토대로 하는 관점이나 연구주제의 정당화에 중요한 역할을 한다. 그러나 이렇듯 다양한 정의 가운데 하나가 최선이라는 것을 입증하거나 다른 정의가 부적절하다는 것을 증명하는 것은 불가능해 보인다. 따라서 도시문화지리학 분야에 있어서 '문화'나 '환경'이라는 개념이 각각 '이것이어야 한다'라고 주장하기 보다는 각각 다루는 주제나 연구자의 관점에 따라 다양한 개념이 유용할 수 있다고 인정하는 태도를 가지는 게 필요하다.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2010년도 춘계학술대회 논문집
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• pp.41-44
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• 2010

Hazardous air pollutants such as benzo[a]pyrene (BaP), benzene, formaldehyde have been concerned about the adverse health effect of long-term exposure. Contour map is useful for finding high-concentration region, emission source, and distributions of HAPs in the ambient air. To make a contour map, we have developed simple analytical method for selected HAPs; polycyclic aromatic hydrocarbons such as BaP, benzene and its derivatives such as toluene and xylene, and aldehydes and ketones. We have applied these methods to investigate air pollution by HAPs in some cities in Japan. The results show that these methods reveal actual emission sources if the PRTR emission report was not submitted.

• 한국가스학회지
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• 제18권5호
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• pp.72-77
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• 2014

우리나라는 영구 동토지역이 존재하지 않는 기후적 특성으로 인해 건설수요가 없었지만, 최근 지구 온난화 현상으로 인하여 화석연료의 사용 보다 극한지 지역의 에너지 확보가 대두되고 있다. 이에 극한지 지역에서 사용하고 있지 못한 에너지 자원의 관심이 증가함에 따라 알레스카 및 시베리아의 천연가스의 개발이 필요성이 증대하고 있다. 이에 따라 극한지 지역에서 필요한 배관 설계 기술은 현재 국내에서 사용되고 있는 천연가스와 전혀 다른 환경에서 운용될 것이 예상되며, 이에 따른 설계 기초 자료가 필요하다. 그러므로 극한지 환경에서의 토양 물성에 따라 배관에 미치는 영향 분석이 필요하다. 현재 배관의 설계는 응력 기반으로 설계되어있지만 추후 변위를 기초하는 설계법이 필요하며, 우선적으로 이를 위한 영구동토층 및 활동층에 대한 영향 분석이 필요하다. 본 연구에서는 유한요소해석을 이용한 Thermal elasto-plastic analysis를 통해 활동층의 영향에 따른 배관의 응력 및 변위 측정을 알아보고자 한다.

• 해양환경안전학회지
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• 제28권1호
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• pp.54-63
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• 2022

해양사고의 조사 및 심판 제도는 유사 사고의 재발을 방지하기 위한 공신력 있는 해결책을 제공하기 위한 것이다. 우리나라의 경우 해양사고가 발생하면 해양안전심판원은 사고의 과정을 정밀하게 분석하여 사고 원인을 공표함으로써 재발방지대책 개발에 기여하고 있다. 그러나 해양사고의 원인으로 제시된 내용이 모호하다면 소기의 목적을 달성하는 데는 어려움이 있을 수 있다. 이러한 관점에서 해양안전심판원의 재결을 살펴보면 일부 사고의 원인으로 적시한 내용을 재발방지대책으로 직접 대입하기 곤란한 몇 몇 경우가 있다. 대표적으로 '선원의 상무로서 준수하여야 할 주의의무를 태만히 한 경우'라는 표현을 들 수 있다. 또한 '선원의 상무'가 정확한 사고원인을 밝히기 어려운 경우에도 선원의 책임으로 돌리기 위하여 관용적으로 사용되고 있다는 비판도 있다. 선원의 상무는 국제해상충돌예방규칙 제2조에 나오는 용어로서 그 사용을 엄격히 하고자, 이 연구에서는 원문에 대한 체계적인 분석을 제공함으로써 선원의 상무와 주의의무에 대한 개념을 비교·정립하고자 한다. 이를 위해 주의의무를 행정적, 민사적, 형사적 시각에서 살펴보고 관련된 판례를 제시하였다. 이에 따라 선원의 상무가 유사 해양사고 재발방지에 기여하는 합목적적인 재결을 위한 용도로 사용되기를 기대하였다.

• Nuclear Engineering and Technology
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• 제37권4호
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• pp.385-390
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• 2005

The effect of the Wolsong Tritium Removal Facility on the change of tritium concentration in the soil water was assessed by introducing a dynamic compartment model. For the mathematical modeling, the tritium in the environment was thought to come from two different sources. Three global tritium cycling models were compared with the natural background concentration. The dynamic compartment model was used to model the behavior of the tritium from the nuclear power plants at the Wolsong site. The source term for the dynamic compartment model was calculated with the dry and wet deposition rates. The area around the Wolsong nuclear power plants was represented by the compartments. The mechanisms considered in deriving the transfer coefficients between the compartments were evaporation, runoff, infiltration, hydrodynamic dispersion, and groundwater flow. We predicted what the change of the tritium concentration around the Wolsong nuclear power plants would be after future operation of the tritium removal facility to show the applicability of the model. The results showed that the operation of the tritium removal facility would reduce the tritium concentration in topsoil water quickly.