• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.774-777
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• 2005

In this paper, a constant frequency phase shifting PWM controlled voltage source full bridge-type series load resonant high-frequency inverter using the IGBT power modules is presented for innovative consumer electromagnetic induction heating applications such as a hot water producer, steamer and super heated steamer. The full bridge arm side link passive quasi-resonant capacitor snubbers in parallel with the each power semiconductor device and high frequency AC load side linked active edge inductive snubber-assisted series load resonant tank soft switching inverter with a constant frequency phase shifted PWM control scheme is discussed and evaluated on the basis of the simulation and experimental results. It is proved from a practical point of view that the series load resonant and edge resonant hybrid high-frequency soft switching PWM inverter topology, what is called class DE type. including the variable-power variable-frequency(VPVF) regulation function can expand zero voltage soft switching commutation range even under low output power setting ranges, which is more suitable and acceptable for induction heated dual packs fluid heater developed newly for consumer power utilizations. Furthermore, even in the lower output power regulation mode of this high-frequency load resonant tank high frequency inverter circuit it is verified that this inverter can achieve ZVS with the aid of the single auxiliary inductor snubber.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.4 no.1
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• pp.7-14
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• 2011

Purpose: The purpose of this study was to analyze the correlation between the medial joint space on weight bearing simple X-ray and the ultrasonographic articular cartilage thickness. Materials and Methods: The articular cartilage thickness of 91 osteoarthritic knees of 73 patients were measured with weight bearing simple X-ray and ultrasonography between June 2010 and September 2010. Male were 13 and female were 60. Right knees were 35, left knees were 20 and bilateral involvements were 18. Medial joint spaces on X-ray were measured in full extension view and $45^{\circ}$ PA(Rosenberg) view. Femoral cartilage thicknesses at and those at the point between the middle 1/3 and posterior 1/3 area were measured by ultrasonography, that were scanned coronally at $30^{\circ}$ flexion and $130^{\circ}$ flexion respectively. The results were analyzed statistically by Pearson correlation test and Bland-Altman plot test. Results: Medial joint spaces measured in full extension view and femoral articular cartilage thicknesses at the point between the anterior 1/3 and middle 1/3 area measured with sonography were statistically correlated and medial joint spaces measured in $45^{\circ}$ PA view and those at the point between the middle 1/3 and posterior 1/3 area measured with sonography were also correlated (P<0.05, $SD{\pm}2$). Conclusion: The measurement of articular cartilage thicknesses by the ultrasonography was easy even in the patient who are unable to take weight bearing view and was thought to be a useful diagnostic and follow up method to examine the degenerative change in addition to simple radiographic examination in the knee osteoarthritis.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.379-381
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• 2009

In designing full vehicle, crash safety, fuel efficiency, exhaust gas, and driving stability are very important factors. Especially, automotive wheel which supports total vehicle weight is a critical component in view of driving stability. Most of automotive wheel have been manufactured for beautiful appearance by using aluminum alloy in domestic industry. However, the amount of automotive steel wheel used are on an increasing trend according to developing the advanced high strength steel with good formability property recently. In this study, the circumferential deviation of rim with various thickness and yield strength was investigated. The formability evaluation of the rim was developed by using a finite element module furnished by Forge software.

• Korean Journal of Human Ecology
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• v.12 no.3
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• pp.287-301
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• 2003

The purpose of this study was to explore the relationship between childrearing belief and parental efficacy of women before and after childbirth. For this purpose 253 pregnant women and 256 mothers with infants under one year of age were contacted and asked to fill in a packet of survey questionnaire at their visits to obstetrician, gynecologist and pediatrician. The questionnaire includes questions about what mothers value in childrearing, their expectations for their children and parental efficacy. Data collected were analyzed using SAS PC program. It was reported that comparing to mothers, pregnant women view childrearing in more ideal lights and expect their children to be more exceptional. Also working mothers reported comparatively lower parental efficacy than full-time mothers suggesting that social support system to minimize pressure coming from work for working mothers with young children should be provided and the parental education methods to enhance the parental efficacy should be sought.

• Bulletin of the Society of Naval Architects of Korea
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• v.19 no.2
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• pp.41-60
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• 1982

The main idea of this report, which deals with the process analysis in outfitting fields, is to improve working methods and further to secure higher productivity by removing unreasonable work factors in the workshop with the economical point of view. For this purpose, a series of techniques has been applied to some parts of chronically less productive outfitting works, expecting less man hour consumption and better working conditions to go with it. That is to make full use of process chart flow diagram(man & machine chart gang process chart). The text gives brief introductions of the charts respectively and the appendix shows actual practice directly applicable for the guidance of utilizing these charts. As the result of this, some of unreasonable work factors are removed from the total cycle and finally standard working method & time can be come out by reasonable working time and gradually improved working method.

• Journal of the Korean Home Economics Association
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• v.42 no.2
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• pp.151-160
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• 2004

This paper researched and compared the Jangsam religious costume, of Buddhism in Yeongsanjae with that of Shamanism in Gutgeori. Jangsam is a full length, flaxen hemp dress used in both religions. (Ed-please amend this sentence as necessary but note that it is essential to give some description of the costume here for non-Korean readers) The religious point of view can cause Jangsam's features to differ Jangsam's meanings are as follows. First, the purpose of wearing Jangsam in both the Buddhist priest's and Shamans' costumes is to gain power from the Almighty in order to maximize the religious effect. Second, Jangsam in the Shaman's costume features universality mixed with Buddhism and folk religion and becomes symbolic in Buddhism. As society disregards Shamanism, it has become combined with Buddhism. Third, Jangsam for Yeongsanjae or Chukwon Gut has kept its religious specialty as a Pyoeui despite various modifications.

• Culinary science and hospitality research
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• v.13 no.1 s.32
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• pp.143-151
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• 2007

The purpose of this study was to fine out a relation to the profitability in the view of market-orientation and examine the roles of marketing efficiency and adaptability in foodservice companies. In the previous studies, because of the concepts of market-orientation have mostly focused on hotels or common companies, in this study aimed to foodservice companies. This study was on the basis of Kohli & Jaworski (1990)'s theory. For the validity verification of measured items, SPSS WINDOW 10.0 was used to analyze factors and, for the reliability verification, Cronbach's Alpha coefficient was used. The result was as follows. First, market-orientation has great influence on customer satisfaction and customer loyalty. Second, customer satisfaction and customer loyalty were acquired for the good marketing efficiency and adaptability in foodservice companies. Thus, from now on, the foodservice company need to carry out the market-orientation concept.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.187-187
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• 2016

진공 압력에 따른 플라즈마 발생의 관계, 전압에 따른 방전 밝기, gas와 방전 전극에 따른 플라즈마 색의 변화 등 실험을 통하여 학부생들에게 진공 시스템과 플라즈마의 이해도를 높이기 위해 Geissler tube cart를 제작하였다. Pump는 TMP station (PFEIFFER Vacuum Hi Cube ECO 80)을 사용하였으며 reducer를 이용하여 CF-4.5"에서 CF-2.75" adaptor를 설치, gate valve를 연결하여 진공도를 조절 할 수 있게 하였으며, 5-way를 이용하여 왼쪽은 gas line, 정면 view port, 상단 geissler tube, 후면 compact full range gauge를 설치하였고, cart 제작 결과를 Fig. 1에 나타내었다. Geissler tube의 수치모델은 Fig. 2에 나타내었다. 저진공(<10-3 Torr) 영역부터 고진공(<10-4 Torr) 영역까지 진공도에 따른 방전을 관찰 할 수 있으며, 표면과 플라즈마 사이의 전위 변화에 따른 쉬스(sheath) 관찰, trans 와 slidacs를 이용하여 전압 조정이 가능하기 때문에 전압에 따른 방전 관찰과 gas line을 통한 gas 주입에 따른 색의 변화를 관찰이 가능하도록 설계하였다.

• Journal of the military operations research society of Korea
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• v.2 no.1
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• pp.185-194
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• 1976

A terminal response time analysis for a general class of terminals-to-computer subsystem is presented in this paper. On the point of the front view, it should be considered for R.O.K. Military Defense to set up the communication network in order to facilitate for the currency of the information and the data communication system. The model used to study is based on the advanced data communications system in which terminals are connected to Terminal Control Units(TCU) that are in turn connected to local Front-End Processor(FEP). The line control procedures used to interface a TCU and an FEP may be half-duplex Binary Synchronous Communication(BSC), half-duplex Synchronous Data Link Control(SDLC), or full-duplex SLDC. This paper will contribute to facilitate the initial phase of system design and configuration for the Military Defense Communication Network System in future.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.112-115
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• 2005

Communication Ocean Meteorological Satellite (COMS) for the hybrid mission of meteorological observation, ocean monitoring, and telecommunication service is planned to be launched onto Geostationary Earth Orbit in 2008. The meteorological payload of COMS is an imager which will monitor meteorological phenomenon around the Korean peninsular intensively and of Asian-side full Earth disk periodically. The meteorological imager (MI) of COMS has 5 spectral channels, I visible channel with the resolution of I km at nadir and 4 infrared channels with the resolution of 4 km at nadir. The characteristics of the COMS MI are introduced in the view points of user requirements, hardware characteristics, and operation features.