• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.239-242
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• 2008

As the distributed generation becomes more reliable and economically feasible, it is expected that a higher application of the distributed generation units would be interconnected to the existing grids. In this context, the Micro Gas Turbines (MGT) by using Bio-gas is being considered as a promising solution. In order to propose a feasible concept of those technologies such as improving environmental effect and economics, we performed a sensitivity study for a biomass fueled MGT using a simulation model. The study consists of 1) the fundamental modeling using manufacturer's technical specifications, 2) the correction with the experimental data, and 3) the prediction of off-design characteristics. The performance analysis model was developed by PEPSE-GT 72, commercial steam/gas turbine simulation technicque.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.7 no.2
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• pp.1-9
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• 2011

Geothermal heat pumps are known as the most efficient and environment-friendly heating and cooling system, and are also gaining acceptance in buildings. Building energy simulation program, EnergyPlus is used to calculate the energy consumption of residential buildings. This simulated energy consumption is essential for accurate economic analysis. Residential buildings with geothermal heat pumps have complex energy price structure. Electricity rates for residential buildings increase rapidly as the monthly use increases. This complex energy price structure makes the economic analysis complicated. The purpose of this study is to conduct economic comparison of residential geothermal heat pumps and provide a feasible approach in finding their economically feasible capacity.

• Journal of the Korean Professional Engineers Association
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• v.42 no.1
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• pp.49-53
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• 2009

Wind energy development and wind farm construction request multi-disciplinary study and coordination to pursuit economically and technically feasible project that may deliver a viable business model. This paper is to provide the study and coordination procedure with key management factors about the wind energy resource assessment and engineering design for EPC(Engineering, Procurement and Construction) contract for the successful business development.

• Journal of the Korean Professional Engineers Association
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• v.15 no.2
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• pp.24-31
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• 1982

This study concerns with the reduction of the COD and deceleration of dyeing wastewater from DAEGU city area by ozonation. The COD reduction by ozonation follows near linear relationships versus ozonation time, temperature and concentration. The color in dyeing wastewater and of dyes can he strikingly reduced as the water is quasi colorless after ozone treatment. COD reduction rate of wastewater was found not to be dependented on pH, however, high temperature gave better results, although economically not feasible. The ozonation of dyeing wastewater can give good results when dyes, scouring agent and sticking agents were pre-separated.

• Archives of Plastic Surgery
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• v.48 no.4
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• pp.389-391
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• 2021

Solo hand surgery is becoming increasingly common, mostly due to a lack of assistants and dedicated operating theatres. The solo hand surgeon faces challenges of proper hand positioning, elevation, and skin flap/tissue retraction. Most commercially available hand retractors or stands do not address all the relevant problems and are not economically feasible for trainee surgeons. The Jain's hand retractor system and stand, described herein, provides solutions to all these problems, and its simple design helps surgeons to reproduce it easily.

• Journal of the Korea Concrete Institute
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• v.28 no.6
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• pp.713-722
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• 2016

The goal of this study was to assess the seismic performance of hollow cast-in-place and precast reinforced concrete bridge columns with triangular reinforcement details. The developed material quantity reduction details are economically feasible and rational, and facilitate shorter construction periods. By using a sophisticated nonlinear finite element analysis program, the accuracy and objectivity of the assessment process can be enhanced. The used numerical method gives a realistic prediction of seismic performance throughout the input ground motions for several hollow column specimens investigated. As a result, triangular reinforcement details were designed to be superior to the existing reinforcement details in terms of required seismic performance.

• Magazine of the Korean Society of Agricultural Engineers
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• v.27 no.4
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• pp.31-41
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• 1985

This paper compares the estimated total construction and maintenance costs for irrigation canals in six irrigation districts near Pyongtaek. Three conventional canal types were considered: concrete bench flumes, concrete-lined canals, and earth canals. The total expenses for each type were grouped to four catagories: the net construction, land acquisition, maintenance, and other expenses. The construction costs included the assumed costs for conveyance losses from each type of canals. The results from this study support earlier studies that the bench flumes are economically feasible. Initially cheaper conveyance systems like concrete-lined and earth canals demand 'higher maintenance costs and thus, their total expenses are summed to exceed those for the bench flumes within a few years following the construction. Banch flumes are economically justifiable for the main canals of the studying districts. Sensitivity analyses were executed to evaluate the relative importance of each expense to the total cost. The analyses show that total expenses very significantly with the change of the following costs: cost for conveyance losses, net construction, maintenance, and land acquisition, in that order However, other expenses contribute little if not at all to the total. The results indicate that bench flumes should be adopted as main canal structures for most irrigation districts in the Republic.

• Journal of Korean Library and Information Science Society
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• v.45 no.3
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• pp.489-511
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• 2014

The purpose of this basic study is to examine the economic feasibility analysis of Busan Central Library, which was included the construction feasibility analysis conducted as one part of the Busan Central Library Construction Master Plan. To achieve the purpose of this study, it was accomplished to do Benefit-Cost analysis, Net Present Value, Internal Rate of Return. CVM(Contingent Valuation Method) was used for calculating the benefit; we investigated two CVMs for Busan Central Library, which are for central construction site and for outer construction site. The results show that the construction of Busan Central Library in the central site would be feasible from the economic point of view. On the contrary, the construction in the outer site would not be feasible economically.

• Food Science and Preservation
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• v.24 no.4
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• pp.491-496
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• 2017

Paddy rice is typically stored during postharvest until rice grain is processed into brown rice and milled rice by hulling and milling procedure, respectively. Recently, instead of storing paddy rice, storage of brown rice has been in the spotlight because it is more convenient and economically feasible. Different brown rice cultivars with varying amylose contents including waxy rice, medium-waxy rice, and non-glutinous rice were stored in room temperature storage for four months, and the changes in grain qualities of brown rice were evaluated. Amylose content significantly affected pasting properties in which rice cultivar with higher amylose content showed longer pasting time and higher peak viscosity. Storage also affected pasting viscosities, showing an increase in peak viscosity, but a decrease in breakdown viscosity. The changes in pasting viscosity during storage could be an important starch property for aged brown rice utilization. Waxy brown rice showed the weakest aging property in terms of free fatty acids (FFA) accumulation, whereas non-glutinous rice was more substantial grain quality against aging. The FFA values of two months storage were not significantly different from the initial FFA contents, suggesting that brown rice stored in room temperature for two months could be feasible for direct consumption of brown rice.

• Journal of Sericultural and Entomological Science
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• v.14 no.2
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• pp.95-103
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• 1972

The major purpose of this study is to collect the information related on the aspects of economic efficiency for solving the problems which are faced by farmers and areas, and providing scientific facts to farmers and related institutions for further development of sericultural sector in Korea. In order for obtaining the related information 12 sample areas among 23 major sericultural farming areas and 30 farm units in each area are selected and analyzed in this study. The fold suevey is made by member of this study team and graduate students in the Department of Sericultural Science with a prepared questionnaires. Cross-section and regression analysis methods are employed for processing the data in this study. The major findings obtained are as followings. 1. Sericultural earnings per Tanbo is, on the average, 22, 752 won in new cultivated areas and 29, 403 won in ordinary ones. There are big difference in the size of earnings by areas, especially, 46, 968 won in Kumo mountain area, compared with 16, 798 won in Yeoju and Yichun areas. General trend is finded that small scale farming units are made higher earnings and operating their farms efficiently. 2. Cocoon production expences per Tanbo is 16, 737 won in new cultivated areas and 19, 802 won in ordinary areas. There are also big difference in farming expences, especially, 27, 389 won in Sudang area, compared with 11, 689 won in Emjin area. 3. Sericultural income per Tanto is 10, 664 won in ordinary areas and 6, 898 won in new cultivated areas. Farmers in Kumo mountain area make the highest income of 21, 164 won and lowest income of 1, 296 won in Sudang area. It can be generized that about 30-50 a sized farmers make higher income. 4. Land, labor and capital productivities estimated by fitting Cobb-Douglas functions in ordinary areas are higher than in new cultivated areas, especially, labor productivity is higher in ordinary areas. 5. Changsung, Kwangna, Yunsun and Kumo mountain areas are technically and economically efficient. Sudang and Mujinchang areas are technically successful but economically inefficient and Emjin and Honam areas are technically inefficient but economically efficient. YeojuYichun, Chunwon and West Kyongnam are technically and economically inefficient. Technical and economic improvement program should be implemented for these areas. 6. Estimated Internal Rate of Return (IRR) on capital investment in Chongwon are is 23.5 percent. It is economically feasible, if we consider 20 percent of opportunity cost of capital in our economy.