• Clean Technology
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• v.9 no.2
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• pp.49-55
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• 2003

The generation of livestock wastewater in Korea amounts to $130,000m^3/day$, 0.43% of the total waste water volume, but which corresponds to 8.6% of total BOD loading. Furthermore this wastewater contains a large amount of nitrogen and phosphorus that are major causes of eutrophication in rivers and lakes. The average volume of livestock wastewater in a Korea's single farm is only $2.5m^3/day$, which necessitates development of a simple and economical process for the removal of nitrogen and phosphorus. Introduction of filtration method removes more than 90% of suspended solids. Subsequent application of reverse osmosis removes more then 95% of total nitrogen and phosphorus in the wastewater. The effluent of this treatment will yield less than 200 mg/L of total nitrogen and 1 mg/L of total phosphorous, which are lower than 260 mg/L of total N and 50 mg/L of total P, the regulation values of Ministry of Environment, Korea. Treating $2m^3/day$ of livestock wastewater was found to be feasible with the application of filtration and reverse osmosis and the electricity requirement was estimated to be about 30 Kwh/month.

• 전기의세계
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• v.43 no.1
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• pp.13-19
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• 1994

전자식 안정기는 최근 에너지 절약 정책과 관련하여 조명기기분야의 관심의 대상이 되었고, 절전 효율이 높은 고품질의 전자식 안정기에 대한 연구 개발 및 보급이 점점 더 확대되고 있는 추세이다. 일반적으로 전자식 안정기는 수십 KHz의 고주파에서 형광등을 구동시킴으로써 빛의 깜박거림과 가청잡음이 없으며, 저주파(60Hz)에서 사용하는 재래식 안정기(choke coil 방식)에 비해 높은 절전 효과를 얻을 수 있다[1-4]. 특히, 빌딩 사무실의 경우 낮에도 창가의 형광등이 켜져 있어서 막대한 전력을 낭비하고 있는 실정이므로, 일조량에 따른 자동 전력 조절이 가능한 전자식 형광등의 출현이 기대되고 있다. 전자식 안정기의 보급 확대를 위해서는 절전 효과 뿐만 아니라, 품질 문제, 수명 문제등을 고려하여야 하는 바, 예를 들면 순간 점등으로 방전초기의 sputtering 현상에 의한 lamp의 수명 단축, 미소 입력전압 변동에 따른 급격한 광출력의 변화로 절전 효과의 상실과 이상동작에 의한 스위칭 소자의 파괴 현상, 고주파 스위칭시 발생되는 전력손실과 noise등에 대한 대책이 요구되고 있다. 이러한 점을 개선하기 위해 추가되는 회로는 전자식 안정기 시스템을 더욱 복잡하게 만들고, 경제적으로 원가 부담을 주기 때문ㅇ 고품질의 전자식 안정기를 보급하는데 어려운 점으로 부각되고 있다. 본 고에서는 이러한 문제를 해결하기 위하여 조광기능을 포함한 다양한 제어회로와 보호회로를 조광기능을 포함한 다양한 제어회로와 보호회로를 1 chip에 수용하는 고품질의 전자식 안정기 제어용 집적회로에 대해서 기술하고자 한다.되어 나아갈 기술의 조류에도 부합하는 형태라 하겠다. 그러나 이 방식은 기 언급한 바와 같이 분산처리를 관장하는 운영체계의 개발에 상당한 고전이 따르리라 보여지며, 또한 보다 상세한 연구가 선행되어야 하겠지만 개발된 상용의 통신 프로토콜로서는 병렬처리의 성능을 극대화 하기에는 여러가지 제약이 있을 것으로 예측된다.기기들이 어떻게 응용되고 있는지 살펴보기로 하자. real informations would be available. Results are compared with those of optimal power flows.기능시험을 완료했으며 실제 line-of-sight(LOS) 시스템 구현에 적용중이다. 시대를 살아 갈 회원들이다. '컨텐츠의 시대'가 개막되는 것이며, 신세기통신과 SK텔레콤은 선의의 경쟁 과 협력을 통해 이동인터넷 서비스의 컨텐츠를 개발해 나가게 될 것이다. 3배가 높았다. 효소 활성에 필수적인 물의 양에 따른 DIAION WA30의 라세미화 효율에 관하여 실험한 결과, 물의 양이 증가할수록 그 효율은 감소하였다. DIAION WA30을 라세미화 촉매로 사용하여 아이소옥탄 내에서 라세믹 나프록센 2,2,2-트리플로로에틸 씨오에스터의 효소적 DKR 반응을 수행해 보았다. 그 결과 DIAION WA30을 사용하지 않은 경우에 비해 반응 전환율과 생성물의 광학 순도는 급격히 향상되었다. 전통적 광학분할 반응의 최대 50%라는 전환율의 제한이 본 연구에서 찾은 DIAION WA30을 첨가함으로써 성공적으로 극복되었다. 또한 고체 염기촉매인 DIAION WA30의 사용은 라세미화 촉매의

• Korean Journal of Food Science and Technology
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• v.25 no.4
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• pp.321-326
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• 1993

Membrane separation technology with polymeric membranes for the effective separation and energy conservation has emerged to be a new technology for separation in recent years. In this research, the reverse osmosis process was applied to the concentration process of clarified apple juices. The changes of concentration and permeate flux of apple juice in this process were measured at different membrane characteristics, operating pressures, temperature and flow rate. And the changes of quality were also measured at different pressures. The prediction model for the permeate flux based on these data was established. Generally, the osmotic pressure increased as the concentration of the feed increased in the RO process, which caused a reduction of permeate flux. The changes of permeate flux were not much dependent on temperature and flow rate, but very much dependent on pressure. The most effective factor in increased permeate flux was found to be the operating pressure, followed by temperature and flow rate. The final prediction model for the permeate flux was developed by the $SPSS^x$ computer program. The result showed that recovery of sugar was not affected by processing pressures, but the percentage recovery of total flavor was increased with increasing pressure.

• Journal of Biosystems Engineering
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• v.12 no.1
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• pp.53-62
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• 1987

Automation of agricultural machinery is a high technology needed to increase work capacity and accuracy, to save agricultural resources and energy, to solve labor shortage, and to improve operator's comfort and safety. With the rapid development of electronic industry, automation of agricultural machinery will be progressed fast, and eventually will lead to no-operator machines or agricultural robots. Automation should be promoted step by step without increasing the cost of farming, excluding rural labor forces, decreasing labor volition, and losing human nature. In order to achieve rational automation of agricultural machinery, it is necessary to investigate the characteristics of soils and crops, to develop sensors, controllers and robots with artificial intelligence. It is recommended that the present trends to directly automatize the individual machinery be changed to the development of a harmonious automation system for overall farming.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.3
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• pp.17-28
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• 2012

This study aims to present the ground for the introduction of energy-saving landscape facilities which can meet the requirements of the age and create a new space by introducing the facilities which saves energy and that users prefer at the space where urbanites enjoy leisure activities in the urban parks. Thus, in addition to a spatial analysis of the parks for 10 urban parks in Gimpo, through an attitude survey on the users' behaviors, the following conclusions were drawn out. First, as a result of putting all facilities in the urban parks in Gimpo, on average, 6.9 out of the standards of 9 (76.6%) have been installed, and as a result of an analysis on the total number of the installed facilities, on average, about 28 kinds of facilities have been installed, so only 22.4% of the total 125 facilities were installed. Second, many urbanites are using the parks for the purpose of taking a walk and exercise to improve their health; however, the legal standards regulate only 2.9 exercise facilities on average in the target area, which are somewhat insufficient. Third, regarding the citizens' intent to participate in responding to climate change, 76% of them showed their intention of participation. Thus, if the energy-saving facilities, the purpose of this study, are introduced, many users will use them, and it is judged that costs for existing street lights and electric power plants will decrease. Fourth, as a result of an analysis of their satisfaction with the facilities, the value of R-square meaning the explanatory power of the independent variables put in a linear model for dependent variables was 0.860, approximately 81% of the total satisfaction, which was a high explanatory power. This study conducted an attitude survey on the users of urban parks in Gimpo at the dimensions of the introduction of energy-saving facilities in the urban parks, the national policies and responses to climate change. It is significant that it identified the appropriateness of developing much more energy-saving landscape facilities needed for low-carbon green growth in various types, and as a subsequent project, a more precision study on this is necessary continuously.

• Clean Technology
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• v.2 no.1
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• pp.32-43
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• 1996

The interactions of the societal-industrial system with the environment form one of the most critical issues in today's world. The inadequacy of current environmental regulatory structures and of traditional ways of analyzing environmental issues, together with the continuing need to mitigate the environmental perturbations arising from this complex relationship, have led to the development of a new conceptual framework termed industrial ecology. Industrial ecology (IE), defined by Graedel and Allenby, is the means by which humanity can deliberately and rationally approach and maintain a desirable carrying capacity, given continued economic, cultural and technological evolution. The concept requires that an industrial system be viewed not in isolation from its surrounding systems, but in concert with them. IE is a systems view in which one seeks to optimize the total materials cycle from virgin material, to finished material, to component, to product, to obsolete product, and to ultimate disposal. Factors to be optimized include resources, energy, and capital. In the present paper, the concept of Industrial Ecology and its application through efficient and practical Design for Environment (DFE) methodologies and tools will be introduced to Korea. This paper will also emphasis on the industrial environment within which DFE methodologies must be used, including the fundamentals of industrial design activities, concurrent engineering, constraints on design choices and existing technological infrastructure.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.642-649
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• 2021

Energy saving standard for buildings are strengthened, the application of exterior insulation finishing system and thickness of insulation materials are increasing. Most buildings with exterior insulation finishing system is applied organic insulating material. Organic insulating material have workability, economic feasibility, reduction in construction cost, and excellent thermal insulation performance. However, Organic insulating material is very vulnerable to heat, so when a fire occurs, rapid fire spread and toxic gas are generated, causing many casualties. Inorganic insulating material can be non-combustible performance, but it is heavy and has low thermal insulation performance. Mineral wool has higher thermal insulation performance than other types of inorganic insulating material, but mineral wool is disadvantageous to workability and vulnerable to moisture. Glass bubble are highly resistant to water and chemically stable substances. In addition, the density of the glass bubble is very low and the particles are spherical, fluidity is improved by the ball bearing effect. Glass bubbles can be used with cement-based ino rganic insulating material to impro ve the weight and thermal insulatio n perfo rmance o f cement-based inorganic insulation. This study produced a inorganic insulating materials were manufactured using cement-based materials and glass bubble. In order to evaluate the insulation performance and flame retardant performance of cement-based super light-weight inorganic insulating materials using with glass bubble, insulation performance or flame retardant and non-combustible performance were evaluated after manufacturing insulating materials using micro cement and two types of glass bubbles. From the test result, Increasing the mixing ratio of glass bubbles improved the insulation performance of cement-based super light-weight inorganic insulating materials, and when the mixing ratio of glass bubbles was 10%, it sho wed sufficient flame retardant and no n-co mbustible perfo rmance.

• Environmental and Resource Economics Review
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• v.30 no.2
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• pp.299-323
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• 2021

This study investigated the impact of information and communication technology (ICT), trade openness, financial development, and economic growth on CO₂ emissions in Korea from 1990 to 2016. The cointegration relationship of the variables was confirmed by an autoregressive distributed lag (ARDL) bounds test. In the long-run, economic growth was statistically significant factor in the increase in CO₂ emissions, while other factors, as well as ICT, did not significant factors in the changes in CO₂ emissions. In the long-run, a link between economic growth and CO₂ emissions has been confirmed, but other factors, including ICT, have not been able to confirm the link between CO₂ emissions in the long-run. Meanwhile, in the short-run, economic growth and ICT increased CO₂ emissions, and financial development led to a decrease in CO₂ emissions. Trade openness did not have a significant effect on CO₂ emissions in the short-run as in the long-run. In particular, ICT did not contribute to the reduction of CO₂ emissions in the short-run as well as the long-run. In order to induce CO₂ mitigation through ICT, the development and deployment of technology that efficiently save energy by using ICT should be further promoted.

• The Journal of the Korea Contents Association
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• v.22 no.2
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• pp.147-161
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• 2022

This study examined changes in the ecological characteristics and design characteristics of Ban's exhibition space in three representative temporary exhibition halls and three permanent exhibition halls designed by Ban Shigeru since 2000. Through the investigation of the concepts and characteristics of ecological architecture, the design characteristics of exhibition space, the analysis framework of the design characteristics of exhibition space and the design elements of ecological architecture is obtained. The analysis results show that there are big changes between the temporary exhibition space and the permanent exhibition space in terms of building scale, space composition, function, materials and technology. On the one hand, the temporary exhibition space used recyclable materials, such as paper tubes, containers to be assembled on site into a single-layer space focused on display. The assembly method was simple and the construction period was short. After the exhibition, the exhibition space were dismantled. The materials were either transported to the next display site or recycled and reused. On the other hand, the permanent exhibition space used reinforced concrete as the main structure, and used a large amount of wood and glass materials to construct a multi-layered composite cultural space that separated the exhibition space and the leisure space. In terms of ecological characteristics, the building materials of the temporary exhibition space were recycled and no industrial wastes were generated after the demolition. The permanent exhibition hall uses eco-friendly wood for the roof and walls, so it is easy to replace and repair. Both types of exhibition halls are changing ecological architecture in a more sustainable direction by saving resources and energy through natural light and ventilation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.26 no.4
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• pp.51-59
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• 2023

Despite countries' efforts to reduce carbon emissions, carbon emissions have increased in recent decades along with energy use, of which building energy uses account for a large proportion. Energy savings are essential as a strategy to reduce carbon emissions in existing buildings. The field experiment on the roof of a building located in Seoul was designed to measure the temperature reduction effect of green roof with rainwater storage tank to reduce cooling energy consumption in summer. The results showed that the mean mean surface temperature under the green roof was 14.77 degrees lower than that of the non-green roof from 13:00 P.M. to 15:00 P.M., which would have a great effect on reducing cooling energy. From 01:00 A.M. to 03:00 A.M., the effect was 3.36 degrees, showing that tropical nights could be improved. The temperature reduction effect due to the rainwater storage system increased by 1.45 degrees during the day and decreased by 0.63 degrees at night. The storage system can be strategically utilized to reduce carbon emissions during the week when cooling energy increases significantly.