• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.229-234
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• 2008

Korea Electric Power Corporation (KEPCO) has started the nation's first biogas-microturbine project in the city of Gongju as an effort to encourage the utilization of wasted biogas containing useful energy source in the form of $CH_4$. The goal of the project is to set up the biogas microturbine co-generation system for utilizing biogas as an energy source and improving the economics of the wastewater treatment plant. Wastewater treatment processes were investigated in depth to find improvement possibility. Changes in internal recirculation ratio and pre-treatment degree are needed to optimize plant operation and biogas production. Biogas pre-treatment system satisfies Capstone's fuel condition requirement with the test result of 99.9% and 90.2% of hydrogen sulphide and ammonia is removal performance. Installation of microturbine and manufacture of heat exchanger to warm anaerobic digester has been done successfully. Expected economic profit produced by the system is coming from energy saving including electricity 115,871kWh/year and heat contained in exhaust gas 579GJ/year.

• Transactions of Materials Processing
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• v.9 no.3
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• pp.233-241
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• 2000

It is well known that the quality and efficiency of the design of metal forming processes can be significantly improved with the aid of effective numerical simulations. In the present study, a two-and three-dimensional finite element simulation system, CAMP form, was developed for the analysis of metal forming processes in the PC environment. It is composed of a solver based on the thermo-rigid-viscoplastic approach and graphic user interface (GUI) based pre-and post-processors to be used for the effective description of forming conditions and graphic display of simulation results, respectively. In particular, in the case of CAMPform 2D (two-dimensional), as the solver contains an automatic remeshing module which determines the deformation step when remeshing is required and reconstructs the new mesh system, it is possible to carry out simulations automatically without any user intervention. Also, the forming analysis considers ductile fracture of the workpiece and wear of dies for better usage of the system. In the case of CAMPform 3D, general three-dimensional problems that involve complex die geometries and require remeshing can be analyzed, but full automation of simulations has yet to be achieved. In this paper, the overall structure and computational background of CAMPform will be briefly explained and analysis results of several forming processes will be shown. From the current results, it is construed that CAMPform can be used in providing useful information to assist the design of forming processes.

• Asia pacific journal of information systems
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• v.25 no.3
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• pp.473-499
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• 2015

The limited literature on Open Source Software (OSS) customers' adoption does not provide explanations on how OSS services are adopted by customers in the presence of functionally superior commercially licensed software (CLS). This paper aims to uncover the process that shapes customer satisfaction of OSS services in comparison to CLS. Expectation Disconfirmation Theory (EDT) is adapted and integrated with pre implementation factor model that influences software customers' expectations including cost, reputation, and experience. The constructed research model is empirically validated using a field survey of OSS and CLS database management system (DBMS) customers in Korea. The theoretical contribution of the paper lies on the application of EDT to explain the wide adoption of OSS DBMS services in the presence of functionally superior CLS DBMSs. Furthermore, this paper integrates EDT with pre-implementation factors for customers' expectations, which has been considered a limitation of the theory. Among the practical contributions, this study draws attention to the substantive differences between OSS and CLS customers' expectations. Additionally, it offers initial explanations for the differences in customer behavior for OSS and CLS and the way that customers' expectations and actual performance are mingled together to form customer satisfaction.

• Advances in aircraft and spacecraft science
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• v.4 no.5
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• pp.543-553
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• 2017

Vibration is a source of performance degradation in all optical imaging systems. Performance of high resolution remote sensing payloads is often limited due to satellite platform vibrations. Effects of Linear and high frequency sinusoidal vibrations on the system MTF are known exactly in closed form but the low frequency vibration effects is a random process and must be considered statistically. Usually the vibration MTF budget is defined based on the mission requirements and the overall MTF limitations. For analyzing low frequency effects, designer must know all the systems specifications and parameters. With a good understanding of harmful vibration frequencies and amplitudes in the system preliminary design phase, their effects could be removed totally or partially. This procedure is cost effective and let the designer to eliminate just harmful vibrations and avoids over-designing. In this paper we have analyzed the effects of low-frequency platform vibrations on the payload's modulation transfer function. We have used a statistical analysis to find the probability of imaging with a MTF equal or greater than a pre-defined budget for different missions. The worst and average cases have been discussed and finally we have proposed "look-up figures". Using these look-up figures, designer can choose the electro-optical parameters in such a way that vibration effects be less than its pre-defined budget. Furthermore, using the results, we can propose a damping profile based on which vibration frequencies and amplitudes must be eliminated to stabilize the payload system.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.1
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• pp.49-54
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• 2003

The purpose of this work is to investigate the effect of premixed fuel on the reduction of exhaust emissions in premixed charge compression ignition engine. The premixed fuel is injected into the intake manifold to form homogeneous pre-mixture in the combustion chamber. The pre-mixture is ignited by a small amount of diesel fuel directly injected into the cylinder. In the case of gasoline as a premixed fuel of the engine, $NO_x$ and smoke concentration of exhaust emissions were reduced compared with the conventional diesel engine. But in the event of diesel fuel for premixed fuel, the rate of smoke reduction was small compared with the case of gasoline as a premixed fuel. HC and CO emissions were increased at high premixed ratio in the case of two premixed fuels. The combustion characteristics of the engine such as the combustion pressure, the rate of heat release, and other characteristics are compared.

• Journal of Nutrition and Health
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• v.30 no.9
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• pp.1073-1083
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• 1997

This project was to compare the effects of consuming diets incorporating soybean oil , canola oil, ad palm oil on blood serum lipid patterns and fecal fat excretion in healthy human adults. The project was composed of three studies that were run concurrently . Each study was composed of a 4-day pre-trial period and two , 14-day experimental periods arranged according to a cross-over design. During the pre trial period, subjects were allowed to eat self-selected diets. During the experimental period , subjects were asked to eat constant, laboratory controlled diets in which sources of dietary fat varied . Thirty healthy , young adult subjects were fed a laboratory controlled diet incorporating soybean oil, canola oil, and palm oil. Test oils provided approximately 20% of the total dietary calories form all sources. Total dietary fat from all sources was approximately 30% of consumed calories. The highest serum total cholesterol , LDL cholesterol, VLDL cholesterol , and triglyceride values occurred when pam oil diets were eaten. However, feeding on palm oil diets resulted in the same HDL cholesterol content as with soybean oil or canola oil diets. Soybean oil diets produced numerically lower blood serum total cholesterol , LDL cholesterol, and triglycerides, and numerically higher HDL cholesterol and VLDL cholesterol than did those with canola oil. Fecal fat excretion was numerically lower with soybean oil diets than with canola diets. The highest fecal fat excretion occurred when palm oil diets were eaten.

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.6
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• pp.127-134
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• 2008

An autonomous reconnaissance ground robot performs its duty in various different environments such as mountain-scape, desert and under-water through changing its shape and form according to the environment it is working in. Making a prototype robot for each environment requires extra cost and time. It is also difficult to modify the problem after production. In this paper, we propose the adoption of M&S(Modeling & Simulation) environment for the production and design of the autonomous reconnaissance ground robot. The proposed method on the M&S environment contributed to the more effective and less time consuming production of the robot through the Pre-Modeling and Pre-Simulation process. For example, we showed the design and implementation of the autonomous reconnaissance ground robot under the proposed environment and tools.

• Journal of Veterinary Clinics
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• v.23 no.4
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• pp.432-436
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• 2006

The therapeutic effects and immune responses with Oidenlandiae Herba administration(17.5%, 1g/30 kg, everyday, PO) were investigated in calves(1 to 3 months old) with diarrhea from 159 Korean native calves(76 heads from A farm and 83 heads from B farm) in Jeju. The causes of 47 calves with diarrhea were coronavirus(1 head) and rotavirus(1 head), coccidium(5 heads) and bacteria(40 herds). PCV values were significantly increased 2 weeks after administration of Oldenlandiae Herba in A form, compared by those of pre-treatment(p<0.05). However RBC, TP, WBC, fibrinogen levels were not significantly changed. The significant difference were not detected in changes of AST, BUN and creatinine. The CD14+ distribution rate were increased in 1 week after administration of Oldenlandiae Herba, compared by that of pre-treatment(p<0.05), however, certain tendencies of changes were not observed in distribution rates of CD4+ CD8+ and CD19+, respectively. The rate of death was 20.1%(36/179 calves) in 2004, however, it was decreased to 12.6%(20/159 calves) by Oldenlandiae Herba administration at 2 farms from Jeju in 2005. In conclusion, the administration of Oldenlandiae Herba was effective for treatment of calves with diarrhea.

• Journal of Technology Innovation
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• v.13 no.2
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• pp.45-70
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• 2005

Much work on innovation has focused on the manufacturing sector. In this paper, we propose a framework for analyzing innovation in services centred on capability and technology integration. We illustrate the theoretical points made by conducting a case study on an international telephone communications provider Brastel, which introduced significant innovations in international calling services, in the form of rechargeable pre-paid calling card, through effective application of standard IT. Brastel is situated against its main competitors, considering two dimensions of price and service breadth and convenience. A novel technique for measuring competitiveness based on price and service index is introduced. The following competitors were selected: NTT, KDDI, Japan Telecom, Fusion Communications, J-Call / World Link, G-Call, ASP Check, Primus, QuickPhone, and MCI. To create the service index, factors such as ease of use, convenience, number of languages in which the services are available, and additional features were taken into account. The company itself and the rechargeable card innovation were analyzed through in-depth interviews and data collection. It was shown that a competitive advantage was maintained through internal and external capabilities.

• International Journal of Human Ecology
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• v.7 no.1
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• pp.67-76
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• 2006

This study delves into the Gache Prohibition Order during the Chosun Dynasty and researches the changes of the Gagye style caused by Gache Prohibition Order comparing both the pre-prohibition order and post-prohibition order and analyzing its related remains, old documents, and other researches about the Gache Prohibition order. The Gache Prohibition order during the Chosun Dynasty had contributed to the changes of the Gagye styles such as Sseu-gye, Hwan-gye, and Eoneun hair styles. Dae-su and Eo-yu-mi Gache in Sseu-gye style had been rarely used while Hwa-gwan and Jok-du-ri were often used in the Sseu-gye style. In the Hwan-gye style, Hwan-gye of Geo-du-mi was replaced with wood. Form and bulk in Eoneun hair had been minimized and changed into new types of The Gache Prohibition order of the Chosun Dynasty had affected the Gagye style in the following ways: First, in the aspect of style, the Gagye style was used to decrease volume. Second, the Practical science of the Chosun Dynasty had affected clothing in terms of actuality, convenience, simplicity, and openness. Third, the Gache Prohibition Order affected the Gagye style as well as the re-understanding of the beauty of clothing.