• 대한환경공학회지
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• 제28권11호
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• pp.1207-1212
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• 2006

본 연구는 담수 퇴적물 중 유기물의 척도가 되는 화학적산소요구량, 염양염류인 총질소와 총인 및 금속류인 철과 망간에 대해 국내 외 분석법을 적용하여 분석을 실시함으로서 각 분석법간의 상관성을 파악하고 그 적용성을 알아보고자 하였다. 화학적산소요구량은 국내 해양환경공정시험방법과 일본의 위생시험법을 적용하였는데 두 방법 모두 측정범위가 넓고, 생물학적산소요구량이나 유기물질과 상관관계가 좋은 과망간산칼륨법을 이용하고 있기 때문에 분석법간 편차가 크지 않음을 확인하였다. 총질소와 총인의 경우 국내 식품공전에 의한 시험법과 일본의 위생시험법을 적용하여 분석을 실시하였다. 총질소는 두 방법 모두 중화 적정법이지만 시료 분해 및 증류 과정의 차이에 의해 일본의 위생시험법에 의한 분석 값이 약간 낮은 경향을 보였다. 총인의 경우 두 방법 모두 질산과 과염소산에 의한 분해 후 값을 측정하는 방법으로 비슷한 결과를 보였다. 철과 망간과 같은 금속류의 실험은 크게 용출방법과 산분해법을 실시하였다. 용출법에서 얻은 결과값은 산분해한 값에 비하여 적은 값을 나타내었는데 그 이유는 용출조건보다 산분해 조건에서 금속류가 더 잘 녹아나오기 때문이다.

• 한국지열·수열에너지학회논문집
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• 제11권3호
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• pp.7-12
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• 2015

Currently water supply system with water storage is generally applied except for small building such as single-family houses, and water supply system on replacing water storage installed system by direct connecting system has been increasing because of sanitary and energy-saving aspects. The purpose of this study is to evaluate energy-saving and environmental efficiency of direct connecting booster pump system in comparison with the water storage installed system. The architectural condition of the evaluation subject is ten-story apartment house in which sixty households live. To calculate the power consumption of the pump, the volume of water supply was determined from existing data and other data, such as head, efficiency of the pump, was the value used for general application in design office. The power consumption of the water supply pump for one day was 8.5 kWh for direct connecting booster pump system, and 22.5 kWh for water storage installed system, and the former system showed energy savings of 62% compared to the latter system. Reduced power consumption also leads to reduction of $CO_2$ emission. According to the criteria presented in the Korea Energy Management Corporation, reducing the 2,410 kg $CO_2$ emission is possible per year.

• 환경영향평가
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• 제6권1호
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• pp.105-110
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• 1997

Sanitary landfill is a general method as a final disposal of municipal solid waste(MSW), therefore leachate characteristics are very various as lime goes by because of highly concentrated organic acids are contained non biodegradable COD. So it is hard to abide by the mandatory standards of discharge eventhough applying the physicochemical and biological processes to treat the leachate. The process of treating leachate are determined by the degree of removal and components, but they are highly contained organic materials. It is a removal method to use jointly with the physicochemical process if the hard and fast rule is needed. The critical components of material are COD, ammonia, salts and heavy metals in the case of treating biologically. Biological process is to use metabolism of microorganism, therefore it is a desirable condition which heavy metals are not contained, because they acting as an inhibitor of enzyme. Of these are contained, organic decomposition and synthetic function of microorganisms decrease significantly. Consequently, this research paper lays emphasis on the concentration of heavy metals in leachate and for the purpose of forecasting the factors which are affecting the leaching of metalic waste in some degree, experimented the various reacting conditions. 1. When the concentration of heavy metals in leachate is in comparison with the level eluted after reaction, at pH 7.9 the result of reaction for PCB to CCL scrap showed that Zn, Mn, Cu was more eluted 11.6 times, 340.3 times, and 2,705.5 times respectively than the leachate undiluted solution. 2. At the condition of strong acid pH 4.7, the concentration of heavy metals in EM undiluted solution showed that Zn, Mn, Cu was more eluted 26.5 times, 147.3 times, and 3,656.3 times respectively than leachate undiluted solution. 3. When the ratio leachate to EM was 50 vs 50(V/V%), Mn was more eluted 198.7 times than leachate undiluted solution, but Zn and Cu do not show the meaningful results. 4. The color of landfill leachate was black-brown. And fulvic acid that is main ingredient of NBD COD contained, oxygen of 44~50%. For that reason, I estimated that the level of Zn, Mn, Cu was higher than the case of leachate. 5. COD of leachate from general landfill is difficult to remove. Because the solution of heavy metals is improved by the character of leachate(pH & ingredient of oxygen etc.) hence the Mn, Cu, Zn act as disturbing factor, the biochemical treatment is hard. Therefore the type of PCB & CCL scrap, iron, aluminum contained metals need to previously separate from general wastes as much as possible.

• 한국환경보건학회지
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• 제30권4호
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• pp.329-343
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• 2004

We conducted to investigate citizen's attitude to the treatment of food waste in Yongin city. The respondent of $41.81\%$ throws the food waste eliminate from home and store less than 1l in Yongin. When they dump the food waste, they speak out the inconvenience of damaged envelope by animals in case of home and store. This caused troubles for reason of sanitary. So a local autonomous entity must carefully consider of expand use specially designed container as like apartment house. They give an answer that the collecting time of food waste is suitable form dawn till morning. This answer shows the satisfaction of the period time to collect the food waste. They prefer to be appointed the exclusive place to collect food waste. The service interval of collect is suitable 1 time a day. They want to increase the number of washing of the collecting container. This is good method for sanitary condition, but the care of the period time to collect the food waste is more efficient than the care of the number of washing the collecting container. The care of the period time minimizes to incur the enmity of the people and to pollute in environment. The major of respondent handled the food waste after keeping the basket or a kit. This fact shows to us almost citizen doesn't feel the seriousness to remove the moisture of the food waste. Recently, many solutions which can be disposal efficiently are getting magnified and improved owing to increase utilities channel to loss in quantities and dry the food waste. We expect the reduction of food waste is solved getting easily step by step. The results of the awareness about the facility of food waste show citizen prefer recycling facility to the other facilities. If recycle facility and incineration facility are constructed, they were worried about bed smell. When some facility of the food waste is constructed, they have to maintain and to handle not to incur the enmity of the people. The spread rate of specially designed container already increased, the citizen set a high value on the use of specially designed container more than amount-rate vinyl envelope that people have used for several years. In the cost treatment about food waste, the major respondent answered the use cost of specially designed container is suitable price. So we can know the use charge is proper level. The majority of citizen more prefer autonomous plan which voluntary atmosphere creation and public information by mass media than levy system and rising treatment cost which forced plan. The citizens have pretty positive thinking of incineration, so the government needs more efforts for a public notice, which includes the incineration is no more than abandoned thing. Each of local self government has to sort the food waste and make kind of resource system related to collecting and carrying, constructing a suitable facility, proper disposal of the food waste and producing harmless in our surrounding in order to solve the invisible problems. To do above mentioned things, we have to analyze referred several problems till now. Also, to minimize the side effect, the government will have to improve through enforce the system.

• 대한영양사협회학술지
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• 제12권3호
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• pp.264-276
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• 2006

The purpose of this study was to propose HACCP system implementation properly and to secure the food safety of school foodservices in Pohang city since the proper facilities and equipment should be key factors in food safety and production. So this study was designed to evaluate existing equipment in food production area, receiving and dining area, and employee facilities. Questionnaire was mailed to 107 school foodservice dietitians in Pohang area and 97 were responded (90.7% response rate). Approximately sixty percent of foodservices were not available separate receiving or polluted area, fifty one percent were installed screen door for insecticidal and temperature and humidity control, and these environmental conditions were hard to keep kitchen dry and sanitary condition. Usually public schools were better equipped than private schools. Forty three percent of school foodservice had initial use of non-foodservice, opened before 1994, and thirty three percent of elementary school foodservice. Among employee facilities, hand washing sanitation stand was prepared seventy nine percent (78.9%) of school foodservices. Dietitians chose outworn equipment and facilities (30.9%), difficulties of maintaining standard temperature and humidity for foodservice (20.6%), lacking separate receiving or polluted area (13.4%), indirect contamination of water hoss (10.3%), and lacking employee facilities (10.3%) as critical points to correct in school foodservice. Therefore governmental regulating agencies must review and approval of plans prior to new construction or extensive remodeling of school foodservice facilities. In addition to these requirement, plan must be set-up step by step to implement HACCP system properly.

• Coupled systems mechanics
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• 제12권6호
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• pp.531-537
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• 2023

Municipal solid waste landfills are unpredictable bioreactors which in cases of mishandling and bad supervision presents numerous risks. The key to municipal waste landfills is to approach them from the point of prevention of the possible consequences, which means using methods of organized waste disposal, and also utilizing landfill gas, as an unavoidable consequence with disposal of municipal solid waste with a high share of biodegradable organic matter. This paper presents an overview about problems of solid municipal waste management, type and composition of waste, and an overview of waste management condition. Further, the problem of landfill and landfill gasses is described with the calculation models of landfill production, as well as the use of the SWM GHG Calculator and LandGEM software on a specific example of gas production for the central zone at Sarajevo landfill "Smiljevici". Main focus of this thesis is the analysis of potentials of greenhouse gas emission reduction measures from the waste management. Overview of the best available techniques in waste management is presented as well as the methodology used for calculations. Scenarios of greenhouse gas emission reduction in waste management were defined so that emissions were calculated using the appropriate model. In the final section of the paper, its description of the problem of collection and utilization the landfill gas at the sanitary landfill "Smiljevici", and implementation of the system for landfill gas collection and solution suggestion for the gasification and exploitation of gas. Energy, environmental and economic benefits can be accomplished by utilizing municipal solid waste as fuel in industry and energy and moreover by utilizing energy generation from landfill gas, which this thesis emphasizes.

• 한국가금학회지
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• 제9권1호
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• pp.17-33
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• 1982

The purpose of this experiment is to clarify the additional effect of antibiotics for the chicken breeding feed. This experiment was carried out with 6,560 individuals which were collected from four farms, Dugil, Hyubhoi, Sanggog and Kumsan. The duration of this experiment was 6 months from July to December in 1981. 1. Body weight and body gain. (1) The range of the body gain was 1.91-7.60% The most effective sections was T$_3$, and the effect was T$_2$, T$_4$, T$_1$, T$\sub$5/ in order. (2) The environmental sanitation of the Sanggog farm was not so good. In this farm the body gain was severely occurred in T$_3$ and T$_2$ sections. Mere gain obtained from T$\sub$5/ section. (3) The environmental sanitation was good in Dugil, Hyubhoi and Kumsan. A little body gain was occurred in these farms, but differences were shown according to the place or breeds. 2. Amount of feed intake feed conversion ratio. (1) Amount of feed intake was increased 0.13-3.19%, and feed conversion ratio was improved 1.68-4.62% compared with control. T$_3$ section showed high percent and T$_4$ T$_1$, T$\sub$5/, Is, C in order. (2) The keeping method of the chicken breed in Hyubhoi was floor brooding. From Hyubhoi and Sanggog farms, the efficiency was increased 9.4-9.8%. (3) From Dugil and Kumsan, the rate of improvement was low. 3. Mortality : Mortality was merely decreased in Sanggog and Kumsan farms which the sanitary and fowl caring conditions had been had, by additional antibiotics. But there was no worthy effect. 4. The ratio of carcass and the degree of skin coloration. The additional antibiotics in feed had no effect on the ratio of carcass but had the influence on the yellowish skin coloration. Skin coloring was good in T$\sub$7/ section and T$_1$, T$\sub$6/, T$_4$, C, T$_3$, T$\sub$5/, T$_2$ in order. 5. Economical efficiency (1) The addition of the antibiotics in feed increased 3.76-10.95% of gross earning. The highest earning was occurred in T$_4$ section and T$_3$, T$_1$, T$_2$, T$\sub$5/, C sections in order. (2) The earning rate was influenced by the antibiotic products. (3) In Dugil and Kumsan farms, there was no difference in earning, however, in Hyubhoi and Sanggog farms there was wide difference in earning. Conclusionally, the addition of antibiotics in chicken breeding feed is necessary. Especially in bad condition of environmental sanitation and floor brooding, the effect of additional antibiotics is clear. Selection of antibiotics from various kinds, maker's confidence and quality problems are important.

• 환경위생공학
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• 제20권1호
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• pp.64-75
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• 2005

2005.1.1부터 직 매립 금지 이후 음식물쓰레기를 처리하는 데 있어 많은 사회적 문제가 대두되고 있다. 그리고 우리나라의 경우 전국 음식물쓰레기 배출량이 11,398ton/day('03)으로 상당히 많은 양이 배출되고 있으며, 주로 음식물쓰레기는 매립, 소각, 사료나 퇴비로 재활용하는 방법으로 처리하고 일부 음식물쓰레기는 혐기성으로 처리 하는 방법이 사용되어 왔다. 이 중 혐기성 처리는 유용한 메탄가스를 발생하여 에너지로 사용가능 하다. 본 연구에서는 pH가 낮고 많은 양의 유기물과 고형물을 함유하고 있어 1단 혐기성 처리시 운전에 영향을 줄 것으로 예상되는 음식물쓰레기의 1단 혐기성처리 가능성 및 혐기성 처리시 메탄가스를 이용하여 에너지로서 사용 가능성에 대해 알아보고자 연구를 실시 하였다. 처리시간과 비용을 절감하기 위해 산형성조를 거치지 않고 반 고형물의 유입시 부유물로 인해 발생될 수 있는 plugging와 channeling 현상을 방지하기 위해 USAB(up flow anaerobic sludge blank)의 장점과 낮은 pH의 음식물 쓰레기의 유입시 미생물에 미칠 수 있는 충격을 최소화 할 수 있는 AE(anaerobic filter)장점을 조합하여 환형유공 지지막속에 그레뉼을 충진시킨 Hybrid Anaerobic Reactor(HAR)를 제작하여 실험을 실시하였다. 본 연구에 앞서 음식물쓰레기의 혐기성 생분해도 실험을 실시하여 혐기성처리가능성을 검토하였으며 실험결과 첨가된 VS량당 총 누적메탄량은 $0.471(m^{3}/\cal{kg}\;VS)$로 원소 분석하여 얻은 이론 메탄발생량 $0.58(m^{3}/\cal{kg}\;VS)$의 $81.2\%$를 나타냈으며 유기물 분해속도 상수는 $0.18(d^{-1})$로 혐기성 처리가 가능하다는 사전 연구 결론을 도출하였다. 연구 결과, 낮은 pH인 음식물 쓰레기를 처리시 산발효조를 거치지 않고도 혐기성 처리가 가능하였으며, 높은 농도로 존재하는 유기물 및 고형물의 처리효율은 매우 양호했고 또한 인의 제거율도 높게 나타났다. 연구결과를 토대로 전국 음식물쓰레기(11,398ton/d)를 대상으로 에너지를 산출하면 Braun에너지 환산계수 $5.97kwh/m3(60\%\;CH_{4})$를 적용할 때 우리나라의 1일 음식물에서 발생되는 에너지 총량은 6,727MWh로 환산될 수 있으며 이는 유기물(COD)당 발생되는 메탄 가스량을 에너지원으로 사용하기에 충분히 가능하다는 것을 확인할 수 있었다. 이상의 결과에 의하면 고농도의 유기물이 함유된 음식물쓰레기는 Hybrid Anaerobic Reactor (HAR)를 이용하여 HRT 30일 정도에서 충분히 직접 혐기성처리가 가능하며, 이때 발생된 $CH_{4}$를 회수하여 이용하면 대체에너지원으로 활용 가치가 높은 것으로 판단된다.

• 한국산림과학회지
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• 제98권1호
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• pp.16-25
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• 2009

꽃송이버섯은 침엽수를 이용하여 재배할 수 있는 식 약용버섯으로 최근 새롭게 인식되고 있다. 그런데, 이 버섯은 낙엽송 심재부후병균으로 악명 높은 갈색부후균이므로 임지 재배를 시도하기 위해서는 신중한 검토가 선행되어야 한다. 본 연구는 이러한 배경 아래 꽃송이버섯의 침엽수림 내 발생환경을 조사하고, 낙엽송의 심재부후에 미치는 영향을 분석하여 침엽수림 내에서 꽃송이버섯 재배를 시도해도 문제가 없는지 검토하고자 수행되었다. 꽃송이버섯은 습도가 충분하고 비옥한 토양에서 자라는 낙엽송, 잣나무, 소나무, 전나무 등 다양한 침엽수림에서 발생하였다. 꽃송이버섯이 발생한 토양은 사양토에서 미사질양토의 범위로써 우리나라의 일반적인 산림토양에 비하여 고운 토성을 지니고 있었으며, pH는 4.6~5.2, 유기물 함량은 4~11%를 나타내 넓은 생육범위를 나타내었다. 꽃송이버섯 균이 침입한 목재는 육안으로 쉽게 파악이 되지 않는 부위에도 이미 균사가 퍼져 있음을 DNA 검정을 통하여 확인하였다. 피해부위는 건전부위에 비하여 함수율은 30% 정도 높은 반면, 압축강도는 30% 정도 낮았다. 꽃송이버섯 균은 뿌리만이 아니라 가지치기 등을 통해 생기는 가지부위의 상처를 통해서도 침입할 수 있으며, 이 경우 포자의 비산이 큰 역할을 하는 것으로 판단되었다. 따라서 꽃송이버섯 균이 나무뿌리 및 줄기부위의 상처를 통하여 쉽게 침입할 수 있음을 감안할 때, 우량목 생산을 위해서는 숲가꾸기의 시기에 유의하여야 하며, 이 버섯의 임내 재배는 신중하게 시도되어야 할 것으로 사료된다. 다만, 위생간벌 등 무육작업을 통해 통기성이 좋은 여건을 유지한다면 성숙림으로 육성하여 우량목재를 생산하는데 큰 문제가 없을 것으로 추론되었다.

• 대한토목학회논문집
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• 제37권1호
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• pp.73-82
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• 2017

우리나라 상수도 기반시설 설비에 관련된 기존의 인증평가는 경제적 측면과 내구성 등 물리적 측면에 초점을 맞추어 사용되어 왔다. 그러나 경제수준이 상승하면서 상수도에 대한 위생, 보건, 안전성, 삶의 질에 대한 국민의식이 향상됨에 따라 상수도 서비스의 위생보건학적 품질향상이 요구되고 있다. 지난 5년간 국내 497개 정수장의 수질분석 자료를 고찰한 결과 pH는 5.8~8.5의 범위로 나타났다. 하지만, 현재 우리나라 수도용 자재 및 제품의 위생안전기준 공정시험방법(위생안전시험법)은 pH 7.0에서만 평가하고 있어, 실제 상수도 pH 조건에서 관내 중금속용출에 대한 기초정보가 부족하다. 이러한 배경으로 본 연구에서는 국내에서 대표적으로 사용되는 관에 대하여 pH변화가 중금속용출에 미치는 영향을 실험적으로 분석연구하였다. 본 연구 결과, pH가 낮아질수록 일부 금속의 용출정도가 증가하는 것을 확인하였다. 특히 pH 5.8일 경우, 구리재질의 관에서 Cu가 보정계수(Normalization Factor) 적용 후에도 위생안전기준을 상회하였다. 스테인레스 재질의 관에서는 Cr, Cu가, 구리재질의 이음관에서는 Cd, Pb, Cu, Zn이, 아연재질의 이음관에서는 Zn이 기준치를 각각 상회하였으나 보정계수를 적용하면 기준치를 만족하였다. 본 연구의 결과로 현행 위생안전시험법에서 pH조건을 7.0 이외의 낮은 pH 조건을 포함하는 개정의 필요성이 제안되었다. 추후 상수도관으로 사용되는 다른 종류의 관에 대한 추가 연구의 필요성도 제시되었다. 본 연구는 차후 우리나라 위생안전기준의 개정연구에 필요한 기초자료 제시에 기여를 하였다.