• Journal of Electrical Engineering and Technology
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• v.6 no.2
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• pp.215-225
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• 2011

In this paper, a buck DC-DC bridge converter is used as a power factor correction (PFC) converter for feeding a voltage source inverter (VSI) based permanent magnet brushless DC motor (PMBLDCM) drive. The front end of the PFC converter is a diode bridge rectifier (DBR) fed from single phase AC mains. The PMBLDCM is used to drive the compressor of an air conditioner through a three-phase voltage source inverter (VSI) fed from a variable voltage DC link. The speed of the air conditioner is controlled to conserve energy using a new concept of voltage control at a DC link proportional to the desired speed of the PMBLDC motor. Therefore, VSI operates only as an electronic commutator of the PMBLDCM. The current of the PMBLDCM is controlled by setting the reference voltage at the DC link as a ramp. The proposed PMBLDCM drive with voltage control-based PFC converter was designed and modeled. The performance is simulated in Matlab-Simulink environment for an air conditioner compressor load driven through a 3.75 kW, 1500 rpm PMBLDC motor. To validate the effectiveness of the proposed speed control scheme, the evaluation results demonstrate improved efficiency of the complete drive with the PFC feature in a wide range of speed and input AC voltage.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2006.05a
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• pp.99-100
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• 2006

The concept of dental clinic have been changed along the advanced dental science to meet the need of setting up high-technology-digital appliances. As the general idea about the dental clinic has been changed from systematic connection, the expansion of zoning needs to become more accurate and mote detailed. In the spacious waiting room. the interment cafe has been established to supply the information services, and the various multi-imaged channels, which were built in, will relieve the boredom of the waiting time. The formation of water space leads to the effect of humidification and makes parents share visual and auditory sympathy All of the unit-chairs attached cameras in the consultation room enables people to diagnose more quickly and precisely through the computerized system. Partitions have been set of to put it in and to help diagnosis process to be done smoothly in the formational space. The whole atmosphere is intended to be harmony with the natural surroundings in Je-Ju. It will inspire people visiting this clinic to image the deep blue sea in Je-Ju. By using projective non-material a lot, especially material wooden windows and doors, it is believed to create the bright and stable atmosphere. It will lead patients feel comfortable.

• Korean Institute of Interior Design Journal
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• no.13
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• pp.3-10
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• 1997

The purpose of this study was to identify the design concepts embedded in our traditional interior space. The majority of this research was achieved through literature review as well as examining traditional Korean houses. The major findings were summarized as follows : First, traditional Korean interior space is contemplative. This is created possible by the careful placement of indispensable furnitures and accessaries resulting in an abundance of unoccupied space. Therefore, the room assumes a peaceful atmosphere which calms the mind and creates a tranquil setting. To enjoy the placidity of Korean interior space a humble demeanor and contemplative thought are required. Next, traditional Korean interior space is modest. This is created by the moderate proportions that do not challenge human scale. Traditional Korean interior space does not dominate its surroundings but rather conforms with them. This contrasts with traditional western houses which utilizes an overbearing scale sacrificing intimate space. Thirdly, traditional Korean interior space is raw. In other words, the materials used in house retain their self-evident natural state and are not artifically manipulated to hide their inherent properties. The fundamental conceptual belief that interior space should not defy nature but instead become part of it. Lastly, traditional Korean interior space is not decorative Rooms are not congested with frivolous aesthetics. Although this does not immediately attract the people's attention, eventually the interior space establishes a unique line of communication with them.

• Journal of Korean Institute of Industrial Engineers
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• v.39 no.5
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• pp.361-366
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• 2013

Prediction of process parameters is very important in parameter design. If predictions are fairly accurate, the quality improvement process will be useful to save time and reduce cost. The concept of dual response approach based on response surface methodology has widely been investigated. Dual response approach may take advantages of optimization modeling for finding optimum setting of input factor by separately modeling mean and variance responses. This study proposes an alternative dual response approach based on machine learning techniques instead of statistical analysis tools. A hybrid neural network-genetic algorithm has been proposed for the purpose of parameter design. A neural network is first constructed to model the relationship between responses and input factors. Mean and variance responses correspond to output nodes while input factors are used for input nodes. Using empirical process data, process parameters can be predicted without performing real experimentations. A genetic algorithm is then applied to find the optimum settings of input factors, where the neural network is used to evaluate the mean and variance response. A drug formulation example from pharmaceutical industry has been studied to demonstrate the procedures and applicability of the proposed approach.

• Journal of Microbiology and Biotechnology
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• v.12 no.3
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• pp.377-381
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• 2002

Recently, interests to remove nitrogen in the nitritation process have increased because of its economical advantages, since it could be a short-cut process to save both oxygen for nitrification and carbon for denitrification compared to a typical nitrification. However, the kinetics related with the nitritation process has not yet been fully understood. Furthermore, many useful models which have been successfully used for wastewater treatment processes cannot be used to estimate effluent nitrite concentration for evaluating performance of the nitritation process, since the process rate equations and population of microorganisms for nitrogen removal in these models have been set up only for the condition of full nitrification. Therefore, the present study was conducted to estimate an effluent nitrite concentration in the nitritation process with a concept of enzymatic inhibition kinetics based on long-term laboratory experiments. Using a nonlinear least squares regression method, kinetic parameters were accurately determined. By setting up a process rate equation along with a mass balance equation of the nitrite-oxidizing step, an effluent nitrite concentration in the nitritation process was then successfully estimated.

• Proceedings of the KSRS Conference
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• v.1
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• pp.159-162
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• 2006

This paper describes the ground system for COMS (Communication, Ocean, and Meteorological Satellite), the first Korean multi-purposed geostationary satellite, at MSC (Meteorological Satellite Center) in Korea. The overview of COMS MI (Meteorological Imager) will be introduced as well. KMA would implement mission planning for COMS MI operation and receive, process, interpret, disseminate, and archive MI data operationally for domestic and foreign user groups. Major missions of COMS MI are mitigation of natural hazard such as typhoon, dust storm, and heavy rain, and short-term warning of severe weather to protect human health and commerce. Moreover, research of climate variability and long-term changes will be supported. In accordance with those missions, the concept and design of COMPASS (COMS operation and meteorological products application service system), the ground system for COMS MI in MSC, have been setting up since 2004. Currently, COMPASS design is being progressed and will have finished the end of 2006. The development of COMPASS has three phases: first phase is development of fundamental COMPASS components in 2007, second phase is to integrate and test all of the COMPASS components in 2008, and the last phase is to operate COMPASS after COMS In-Orbit Tests in 2009.

• Journal of The Korean Association For Science Education
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• v.13 no.2
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• pp.198-209
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• 1993

This paper was made for the purpose of research for newly formed of Common Science subject and setting up for Common Science subject's place. For this purpose, I 1) reviewed the bacground of curriculum revision and newly formed Common Science subject. 2)reviewed the change of the current of science education and the study of Common Science subject in Korea. 3) examined Common Science subject as integrated science The results were as follow: l.Newly formed of Common Science subject motivated by current of science education in the wordwide, direction of the 6th curriculum in Korea and the actual condition of integrated science in foreign country. 2.1t emphasize on learning of inquiry method than system of knowlege,introduction to material connected with real life and science and technology in society in the Common Science subject. In principle,the level of concept in Common Science subject keep within level of Science subject in middle school. 3.Common Science subject is characterized by integrated science. And Common Science subject have to become more integrated science in the textbook and the teaching-learning as well as in curriculum.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2002.05a
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• pp.251-259
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• 2002

The design concept of diesel engines for sea-going ships has been directed to Low-speed/Long-Stroke type to improve the efficiencies of combustion and propelling. But the time-delay property inevitable at such low speed engines gives much difficulties for governors to control the engine speed because they would be apt to go into unstable region especially when operating at low speed. The purpose of this paper is to study the problem of how the governor gain can be calculated dynamically in accordance with the variance of engine speed at least for an engine to be stable. In this study, the property of diesel engine was described as composed of combustion element including dead time and rotating element, and the ultimate gain for the speed control system to be located on the condition of stability limit was proposed based on the frequency characteristics. And the target gains with optimized stability also were proposed by giving proper margin to these ultimate conditions. The results were applied to a model system and the availability was confirmed to be satisfactory.

• The Research Journal of the Costume Culture
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• v.15 no.6
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• pp.1063-1077
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• 2007

The purpose of this research is to comprehend the various range of expressions of fantasies and to summarize the expressive effects of fantasies that appear most commonly in today's popular culture such as film and fashion. The followings are the results of the research: Fantasy means a genre of literary arts, which uses magic and supernatural figures as the themes or plots. The characteristics of the expressive effects of the costumes in fantasy movies are summarized as metaphor and symbol, hybrid, otherness, grotesque. After analyzing the costumes in fantasy movies, it is concluded that these characteristics can be conceptualized as the characteristics of the expressive effects in the field of fashion and they can be used as the basis in setting the visual images. This research also aims at recognizing and predicting the fashion trend by understanding closely at the popular cultures, using the films as a tool, which can be led to examining the possibility of combining various popular cultures.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.4
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• pp.1-16
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• 1999

Critical is used frequently in many test generation procedures. In this paper, the critical-pair is defined as a extended concept of critical. Also, the criticality, the critical rate, the critical number, and the critical setting rate are defined which represent the characteristics of critical. In these elements, it is proved that the usage of the critical-pair is more efficient than that of the single critical. in FFR, it is also showed that the critical-pair is more efficient in evaluation number of critical values when the test pattern is generated, in the number of searching lines, and the test generation time. The experimental results of the critical-pair on the ISCAS85 benchmark test circuits are compared and analyzed to the single critical using simulation.