• 자원ㆍ환경경제연구
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• 제10권3호
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• pp.413-431
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• 2001

Previous analyses of deposit-refund systems (hereafter DRS) mosty concerned consumer-paid DRS. While there has been a trend to put more emphasis on the producers' responsibility in recycling, especilly in Europe, and the supplier-paid DRS has been enforced in Korea during the past decade, little attempt has been made to analyse rigorously the nature of the supplier-paid DRS. This paper looks into the effects of the supplier-paid DRS on firm behaviors and profits under the oligopolistic market structure. It is shown that, in the cournot model where firms strategically interact each other, when the deposit rate is high enough, firms' profit increase as the deposit rate rises. Furthermore, where the number of firms are sufficiently large, it can happen that, as the deposit rate increases, both social welfare and firms' profit improve.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.264-269
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• 2000

As a part of the ongoing effort towards commercial application of high-temperature fuel cell power generation systems, we have recently built a pilot-scale molten carbonate fuel cell power plant and tested it. The stack test system is composed of diverse peripheral units such as reformer, pre-heater, water purifier, electrical loader, gas supplier, and recycling systems. The stack itself was made of 40cells of $6000cm^2$ area each. The stack showed an output higher than 25kW power and a reliable performance at atmospheric operation. A pressurized performance was also tested, and it turned out the cell performance increased though a few cells have shown a symptom of gas crossover. The pressurized operation characteristics could be analyzed with numerical computation results of a stack model.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.325-328
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• 2009

The 10t/d pyrolysis demonstration plant have been developed for waste tire recycling treatment and value added commercialization. The initial plant model had been started under 2.4t/d capacity with continuous operation, and the commercial plant has been achieved to the 120t/d based on demonstration plant having the tube reactor with chain conveyer attached disk. The next generation pyrolysis plant for waste tire is reviewed and the assignment for plant development is presented briefly.

• 산업경영시스템학회지
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• 제32권4호
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• pp.192-202
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• 2009

Disassembly of products at their end-of-life (EOL) is a prerequisite for recycling or remanufacturing, since most products should be disassembled before being recycled or remanufactured as secondary parts or materials. In disassembly sequence planning of EOL products, considered are the uncertainty issues, i.e., defective parts or joints in an incoming product, disassembly damage, and imprecise net profits and costs. The paper deals with the problem of determining the disassembly level and corresponding sequence, with the objective of maximizing the overall profit under uncertainties in disassembly cost and/or revenue. The solution is represented as the longest path on a directed acyclic graph where parameter (arc length) uncertainties are modeled in the form of intervals. And, a heuristic algorithm is developed to find a path with the minimum worst case regret, since the problem is NP-hard. Computational experiments are carried out to show the performance of the proposed algorithm compared with the mixed integer programming model and Conde's heuristic algorithm.

• 토지주택연구
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• 제14권1호
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• pp.123-134
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• 2023

설계단계에서 작성된 BIM모델은 후속 단계 전환을 통한 사전검토 및 공정관리 등에 활용될 수 있다. 그러나 실제 BIM적용 사례들의 경우 설계단계와 시공단계의 활용 목적성 등의 차이로 인해 설계단계의 모델의 활용이 아닌 시공단계에 적합한 새로운 모델을 작성하는 등 추가 작업이 요구된다. 따라서 본 연구에서는 시공단계에서 재작성 없이 설계단계 BIM모델의 재활용 방안으로 객체 분할을 제안하며, 이를 위해 객체의 기본요소인 정점 데이터를 기반으로 분할 면을 생성하여 객체 분할에 활용하는 방법론을 제시한다. 또한 실제 BIM모델에 적용 및 분할 객체의 4D CAD 시스템 연동과 기존 분할 방법과의 비교를 통해 활용성을 검증한다.

• Asian-Australasian Journal of Animal Sciences
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• 제33권7호
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• pp.1209-1216
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• 2020

Objective: The present study aimed to evaluate the performance of odor abatement by using two different ventilation-biofilter systems with recycled stablized swine wastewater. Methods: The performance of odor removal efficiency was evaluated using two different ventilation-biofilter-recycled wastewater arrangements. A recirculating air-flow ventilation system connected to a vertical biofilter (M1) and a plug-flow ventilation system connected to a horizontal biofilter (M2) were installed. Water dripping over the surface of the biofilter was recycled at a flow rate of 0.83 L/h in summer and 0.58 L/h in winter to reduce odorous compounds and particulate matter (PM). The experiments were performed for 64 days with M1 and M2 to investigate how these two ventilation-biofilter systems influenced the reduction of odor compounds in the model houses. Odorous compounds, NH₃ and volatile organic compounds (VOCs) were analyzed, and microclimatic variables such as temperature, humidity, and PM were monitored. Results: Ammonia concentration inside M1 was about 41% higher on average than that in M2. PM and total suspended particles (TSPs) inside M1 were about 62.2% and 69.9%, respectively, higher than those in M2. TSPs in the model house were positively correlated with the concentration of NH₃ and VOCs. Conclusion: M2 emitted lower concentration of odorous compounds than M1. Moreover, M2 could maintain the optimum temperature condition for a swine house during the cooler season. The plug-flow ventilation-horizontal biofilter system could be used for pig houses to minimize air pollution produced by swine farming activities and maintain optimum microclimate conditions for pigs.

• 한국환경보건학회지
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• 제35권6호
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• pp.526-531
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• 2009

Waste generation was generally expected to steadily rise due to a rapid increase in population and economic growth. However, regulations on disposable goods and a volume-based waste fee system have led to a gradual reduction in the amount of waste. In the case of food waste, separation of food waste from other waste has been put in place since direct landfilling was banned in January 2005. The predicted generation amounts of food waste and wastewater in the model city were 54 ton/d and 127.3 ton/d by year 2020, respectively. However, appropriate treatment technologies for food waste and wastewater discharged from food waste treatment processes are yet to be established. In this study, the food waste and wastewater discharged from food waste treatment process in the model city were characterized by literal and field investigation.

• 유기물자원화
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• 제24권1호
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• pp.3-10
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• 2016

질산과 염산에 의한 대나무활성탄(bamboo-based activated carbon, BAC)의 개질이 Pb(II)와 Cu(II)의 흡착특성에 미치는 영향을 규명하기 위해 회분식 흡착실험을 수행하였다. 산 개질에 의해 BAC의 탄소함량은 감소하고 산소함량은 증가하며 pH는 감소하는 것으로 나타났다. 염산에 의한 개질은 BAC에 뚜렷한 표면작용기를 첨가시키지 않았으나 질산에 의한 개질은 카르복실기와 OH 작용기를 첨가시키는 것으로 나타났다. BAC와 산으로 개질된 BAC의 중금속 이온 흡착속도는 2차 속도모델에 의해 적절하게 설명될 수 있는 것으로 나타나 흡착반응의 속도가 물리적 흡착보다는 흡착제와 금속이온들 사이의 전자들의 공유나 교환을 포함하는 화학적 흡착에 의해 결정되는 것으로 나타났다. 실험에 사용된 모든 흡착소재의 등온흡착특성은 Langmuir와 Freundlich 모델에 의해 적절하게 설명될 수 있으며 BAC의 염산에 의한 개질은 중금속 이온의 흡착용량에 큰 영향을 미치지 않으나 표면작용기를 첨가시킨 질산에 의한 개질은 Pb(II)와 Cu(II)의 흡착용량을 각각 36.0%와 27.3% 증가시키는 것으로 나타났다.

• 한국가정과교육학회지
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• 제35권2호
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• pp.41-59
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• 2023

본 연구는 가정과 교사의 푸드리터러시 함양을 위한 식생활교육 요구도 분석하여 푸드리터러시 함양을 위한 중등 가정과 식생활교육의 발전 방향을 제시하는 것을 목적으로 하였다. 연구 목적을 달성하기 위해 192명의 가정과 교사를 대상으로 푸드리터러시 교육의 내용 영역과 내용 요소에 대한 중요도와 현재 실행도에 대한 인식을 조사하고, 교육 요구도 조사 결과를 기반으로 푸드리터러시 교육을 위한 내용 영역과 내용 요소의 우선순위를 파악하였다. 가정과 교사는 제시된 38개 내용 요소 중 34개 내용 요소에 대하여 중요도에 비하여 현재 실행도를 유의적으로 낮게 인식하고 있었다. Borich의 교육 요구도 공식과 The Locus for Focus Model을 활용하여 교육 요구도가 '매우 높은' 5가지 내용 요소('식량 주권/식량 안보', '식품 관련 쓰레기 저감화', '음식물쓰레기 처리와 재활용', '식품 관련 쓰레기와 분리수거', '원산지 정보')를 도출하였으며, 다음으로 요구도가 '높은' 4가지 내용 요소('유전자 변형 식품', '윤리적 소비', '식품 첨가물', '친환경 농산물')를 확인하였다. 요구도가 매우 높은 것으로 나타난 내용 요소는 '생산' 영역과 '폐기' 영역에 해당하는 것으로 나타나 '생산'과 '폐기' 영역에 대한 교육 요구도 역시 높음을 알 수 있었다. 따라서 향후 가정과 푸드리터러시 함양을 위한 식생활교육을 위해 식품의 생산과 폐기를 강조하여 다루는 것이 필요하며, 이 외에도 푸드리터러시 함양을 위한 가정과 식생활교육의 세부 내용 및 콘텐츠 개발을 위한 연구가 필요하다. 본 연구의 결과는 영양 및 식품에 대한 지식 습득과 개인 차원의 식품 소비 단계를 중심으로 구성된 기존의 식생활교육의 패러다임에서 벗어나 학생들이 식품의 생산에서부터 폐기까지의 전 과정을 학습할 수 있는 새로운 가정과 식생활교육의 필요성에 대한 시사점을 제안할 수 있다. 또한 중등 가정과 푸드리터러시 함양을 위한 식생활교육의 기초 연구로 활용되기를 기대한다.

• 한국안전학회지
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• 제20권4호
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• pp.63-70
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• 2005

It has been used so many kinds of architectural materials and interior products in current building construction, and use of composite architectural materials is increasing with the development of chemical technology. As the green architecture has become the center of public interest, much effort is conducted in advanced countries on the LCA point of view, such as restriction of architectural materials that emitting pollution substances, developing of Non-Toxic architectural materials, and recycling of used materials, etc. with the cooperation of related organizations, material manufacture companies, and construction companies. Because the kinds of materials to be used in building constructions are so various, there might be some possibility of personal and subjective choice at the time of materials selection resulting the missing the requirements of building components and the choice of harmful materials to human. One way to resolve the material problem is to present the green architectural materials which coincide with the quality performance at service and not harmful to man and nature. At this point of view, this study aims to develop the material classification model by investigating the major labelling system about green architectural materials in both domestic and abroad and to implement an efficient material selection system by making a powerful database of environmental standard and quality basis of building requirements.