• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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• pp.764-769
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• 2000

A new transplant production system that produces high quality plug seedlings of specific crop has been studied. It is a plant factory designed to produce massive amount of virus free seedlings. The design concept for building this plant factory is to realize maximum energy efficiency and minimum initial investment and running cost. The basic production strategy is the sitespecific management. In this case, the management of the growth of individual plantlet is considered. This requires highly automated and information intensive production system in a closed aseptic environment the sterilized specific crops. One of the key components of this sophisticated system is the irrigation system. The conditions that this irrigation system has to satisfy are: 1. to perform the site specific crop management in irrigation and 2. to meet the no waste standard. The objective of this study is to develop an irrigation scheduling that can implement the no waste standard.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2006년도 춘계학술발표회 논문집
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• pp.271-276
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• 2006

Railroads made many contribution to modernization being developed so quickly as public transportation, but after middle of 20 century, its qualities are getting low because of focusing on the investment and development of cars and airplanes. Its role which is getting the excellent merits on the mass transportation, rapid transit. safety, state period, energy efficiency, and prevention of environmental pollution has been reconsidered. Element of horizontal alignment In an existing railroad line is needed as basic materials, when it will be improved or moved. If its design drawing was lost or damaged, it is impossible to recover. It is riot easy to repair for it as disasters. We must understand an existing railroad line to bring a function included a basic geography situation. In this studies we acquire, analyze. and handle the digital picture of railroads and then reappear shape of three dimension. But also we want to contribute to establish the facilities information choosing materials of existing railroad line in outputting the alignment element by reverse.

• International Journal of Safety
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• 제3권1호
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• pp.15-19
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• 2004

A new tower internal, which is called CSE, is presented. The CSE is composed of a nozzle perforated in its bottom along the entire periphery and equipped with a multi vane axial swirler at the inlet and hollow cylindrical separator at the outlet of the nozzle. According to the experimental work for obtaining the necessary hydraulic information of the CSE, which is used for preliminary design of a separation column, the CSE showed a stable operation over the wide rage of gas/liquid ratio. However, it caused large pressure drop due to the high gas velocity which should carry liquid droplets through the element. The high pressure drop may cause problems in energy recovery and the application of the CSE can be limited to the high pressure columns. Assuming that the tray efficiency of the CSE is the same with the existing separation columns, the results of the column design showed the size reduction of the column diameters by 30 to $40\%$ and investment cost saving, depending on operating conditions. The application of the CSE to separation column may also contribute to the de-bottlenecking the existing column.

• 대한기계학회논문집B
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• 제22권11호
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• pp.1547-1554
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• 1998

The object of this study was to develop an economic assessment program for the optimal design of the cogeneration systems composed of combining engine, generator, waste heat recovery exchanger, absorption chiller, and boiler, etc. The energy demand categorized by electric power, heating, cooling and water supply was determined by statistical data of the existing cogeneration systems. An economic assessment was performed by comparing the total cost of cogeneration system with that of non-cogeneration system. The total cost was evaluated by adding initial investment to operational cost considering efficiency of equipment, cost of equipment, fuel and electricity. To confirm the validity of the developed program, a hotel building with an area of $127,960m^2$ was selected, and the simulated results were compared with the measured data. The difference between the simulated and the measured values for the selected hotel building was approximately 12% for annual electric consumption.

• Journal of Advanced Marine Engineering and Technology
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• 제23권5호
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• pp.670-678
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• 1999

Heat recovery steam generator(HRSG) is a principal component of the combined cycle power plant (CCPP) which utilizes the waste energy of the gas turbine exhaust gas. A design of the HRSG is a keypoint to achieve high cycle efficiency with competitive cost. This paper presents a brief review on the design of a HRSG which covers the basic design parameters and their effects on the performance and the investment cost. Finally the concept of the optimum design point is presented according to the selection of a pinch point temperature difference and a steam pressure as an illustrated case.

• 전기학회논문지P
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• 제63권4호
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• pp.333-338
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• 2014

This paper concerns the development of the transformer that can reduce harmonics supplied to the system if the output of photovoltaic inverter in the photovoltaic system is grid-connected, and suggests that problems of harmonics and power factor degradation in the grid-connected photovoltaic system can be improved. In this study, the burden of increasing the investment in new facilities and securing their installation space due to harmonics has been substantially eased through the development of a hybrid transformer possessing unbalanced function and harmonics reduction function using zig-zag coils, and most of all, it is expected that the development of such high efficiency hybrid transformer possessing functions of transformation and reducing harmonics can improve the power quality as well as prevent damages caused by harmonics, leading to suppress unnecessary loss of electric power and thereby contribute to energy savings.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.742-749
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• 2008

In 21th century, high oil price and environmental pollution appeared by serious social problem. It brought important change of logistics environment, and environmentally-friendliness and sustainability are emphasized. In spite of that railroad has high energy efficiency and environmental-friendliness to advantage traditionally, there is still transport division rate of railroad in declining tendency as investment policy that is concentrated on road and insufficiency of social realization about environmental problem. The construction of environment-friendly transport system and the reasonable role sharing between modes of transportation are important. Transportation policy of Korea is presented through plans to constructs efficiently and manages national transportation system. In this study, examine development process of national railroad logistics plan with logistics environment change, and proposes the following ways to development of railroad logistics policy.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.434-439
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• 2005

In order to prevent the global warming, Korea has had a ratification to the Kyoto Protocol which is specified the air pollution level should be lower the condition of the year 1990 until the year 2012, in hence the traffic system produced mostly the air pollution has been faced to big change. According to the reinforcement of higher level for environmental condition, alternative way to the conventional traffic system is required, so that is fuel cell technology of commercialized R&D program used by hydrogen fuel, and further for the optimized high energy efficiency it has been considered the advanced development of traffic system used the conventional railroad system. But it is moreover expected the huge amount of initial investment, so at the current, next new traffic system is needed. This study is for the improvement of urban traffic system in domestic which should be seriously changed for environmental friendly through the reduction of air pollution by fuel gases of vehicle and human convenience to be easily approached. In hence it is proposed the development of superior high efficiency-'Fuel-cell Rubber-tired Tram' system manufactured by the composite car-body.

• 한국가스학회지
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• 제22권4호
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• pp.63-73
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• 2018

잉여전력 등을 활용한 에너지저장시스템 분야에 기술에 관심이 집중되고 혁신적인 기술진보가 이루어지고 있다. 다양한 에너지저장시스템 분야 중 가스액화 방식을 활용한 액화공기에너지저장 시스템은 상당히 성숙된 기술로 알려져 있고, 높은 단위 에너지 밀도와 설치에 따른 지형적 제약이 거의 없으며 수명이 긴 저장 시스템이라는 많은 장점에도 불구하고, 단일공정 (공기액화-재기화 사이클)의 낮은 사이클 효율로 인해 상업화에 한계가 있었다. 본 연구에서는 낮은 사이클 효율을 개선하고자 2종류의 냉매(R-600a 와 메탄올)을 이용한 냉매사이클을 공기 액화 공정에 활용하여 사이클 효율을 향상시키고, 공기 압축시 발생하는 압축열을 열매체유 순환 사이클에 이용하여 이를 액화공기 재기화 공정의 터빈 입구 온도를 높이는데 활용하여 전력생산량을 추가적으로 증가시킴으로써 사이클 효율을 획기적으로 향상시킬 수 있는 가능성을 Aspen HYSYS 공정 모사 프로그램을 활용하여 확인하였다.

• 한국유기농업학회지
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• 제17권3호
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• pp.307-326
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• 2009

The present study suggests a concept of resources circulation type agriculture and a concept of a livestock zone related to it and evaluated economical efficiency about a possibility of the resources circulation type livestock zone based on the concept. As a result, when the resources circulation type livestock zone is operated in an area of 1,300ha, it was evaluated that the profit of 11,244 hundred thousand won per year is generated, compared to the conventional agriculture. When light and heat expenses and roughage of Hanwoo production, production of TMR forage as well as income of the energy and composting business of livestock manure at the recycling center were considered in addition to that, it was judged that the present zone development bushiness has enough business feasibility. However, it is necessary that the support regulations, etc. is constructed so that all produced compost byproducts are used at farmhouses and the system related to facility investment assurance and assistance of operating expenses is maintained. It is thought that the complement of a system is also necessary so that energy or power generation expenses can be operated in the same conditions as other new & renewable energy, and the nation's purchase of carbon credits(CDM) is investigated and systemized in the early period, and construction of a revitalization plan of the business through budget securing of the Ministry of Agriculture and Forestry related to the trade of CDM and carbon emission rights is also a business that should be urgently developed. In the future, the change of an outside environment will further promote use of the energy. Also, as people, who don't know agriculture. farm village, increase day by day because of population concentration in a city, an opportunity that can new added value through experience tourism or educational programs utilizing them is increasing. Accordingly, if programs utilizing social characteristics, such as utilization as a space of tourism. leisure. experience, system construction of bio-energy and system construction that Micro Grid or Smart Grid as a dispersed storage and generation system is stabilized, are constructed, it can be said that revitalization or success conditions of the zone is further achieved.