• Journal of Chest Surgery
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• 제11권1호
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• pp.97-101
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• 1978

Primary cyst of the diaphragm is a rather uncommon disease. This is a report of a case of diaphragmatic cyst, located in the tendinous portion of the right diaphragm. The patient had no specific symptoms in the respiratory systems, but suffered from gastrointestinal symptoms [indigestion, epigastralgia, and loss of appetite etc.] for 2 months. Accidentally, on a simple chest x-ray examination, a round homogenous mass density was discovered. Tomography showed a well circumscribed parenchymatous mass. So a coin lesion in the medial segment of the right lower lobe was suspected. A thoracotomy was performed. There were no pathological findings in the lung and pleura. A ping-pong ball sized round mass, which was soft, elastic and fluctuated,was noted in the tendinous portion of the diaphragm. It was enucleated completely without diaphragmatic rupture, and diagnosed as a primary diaphragmatic cyst [fibrous-walled] by the histopathologic examination. Postoperative course was uneventful.

• Journal of Chest Surgery
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• 제4권2호
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• pp.87-90
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• 1971

The mediastinal lipoma is an extremely rare tumor in children. Since the orininal description by Fothergill in 1781, about 120 cases have been reported in the world literature. Of these, less than 10 have been reported in children below the age of 12. We had experienced a posterior mediastinal lipoma in 3 year old boy. He did not complain of any subjective symptoms. Routine X-ray film revealed a huge round homogenous mass density in the posterior mediastinum. On posterior thoracotomy incision,bright yellow,well encapsulated, partly 1obular adipose mass was found in the posterior mediastinum. The tumor mass was removed easily,being proved to be lipoma on histopathologic examination. His postoperative course was uneventful and discharged on the 12th postoperative day.

• Tribology and Lubricants
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• 제27권2호
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• pp.77-87
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• 2011

In this study, using the governing equation for thermohydrodyamic lubrication involving the homogeneous mixture of incompressible fluid derived by based on the principle of continuum mechanics, it is discussed the effects of water within turbine oil on the performance of high speed journal bearing of a steam turbine shipping engine. The governing equation is the general equation being able to be applied on the mixture of Newtonian fluid and non-Newtonian fluid. Here, the fluid viscosity index, n of power-law non-Newtonian fluid is supposed to be 1 for the application of the journal bearing in a steam turbine shipping engine lubricated with the mixture of two Newtonian fluid, for example, water within turbine oil. The results related with the bearing performance are showed.

• Bulletin of the Korean Chemical Society
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• 제29권1호
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• pp.159-164
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• 2008

Two kinds of CNT/TiO2 composite photocatalysts were synthesized with multi-walled carbon nanotubes (MWCNTs) and titanium(IV) n-butoxide (TNB) by a MCPBA oxidation method. Since MWCNTs had charge transfer and semiconducting, the CNT/TiO2 composite shows a good photo-degradation activity. The XRD patterns reveal that only anatase phase can be identified for MCT composite, but the HMCT composite synthesized with HCl treatment was observed the mixed phase of anatase and rutile. The EDX spectra were shown the presence as major elements of Ti with strong peaks. From the SEM results, the sample MCT and HMCT synthesized by the thermal decomposition with TNB show a homogenous sample with only individual MWCNTs covered with TiO2 without any jam-like aggregates between CNTs and TiO2. From the photocatalytic results, we could be suggested that the excellent activity of the CNT/TiO2 composites for organic dye and UV irradiation time could be attributed to combination effects between TiO2 and MWCNTs with plausible photodegradation mechanism.

• 한국통신학회논문지
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• 제29권1C호
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• pp.50-58
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• 2004

본 논문은 수정된 이방성 확산 펄터를 이용한 영상 개선 방법을 제안하였다. 이를 위하여 최소 신뢰 스케일을 기반으로 하는 센서 잡음 추정과 스케일 스페이스 방법을 도입하였다. 이때 이방성 필터는 구해진 임계값 함수와 국부 기울기에 의해 수정되었다. 모의 실험을 통해 제안한 방법이 평탄 영역에서의 잡음을 거의 증폭시키지 않으면서도 뛰어난 에지 향상을 보임을 증명할 수 있었다.

• 한국통신학회논문지
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• 제29권1C호
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• pp.45-49
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• 2004

본 논문은 수정된 이방성 확산 펄터를 이용한 영상 개선 방법을 제안하였다. 이를 위하여 최소 신뢰 스케일을 기반으로 하는 센서 잡음 추정과 스케일 스페이스 방법을 도입하였다. 이때 이방성 필터는 구해진 임계값 함수와 국부 기울기에 의해 수정되었다. 모의 실험을 통해 제안한 방법이 평탄 영역에서의 잡음을 거의 증폭시키지 않으면서도 뛰어난 에지 향상을 보임을 증명할 수 있었다.

• 한국전기전자재료학회논문지
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• 제23권3호
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• pp.183-189
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• 2010

In this paper, the trench gate emitter switched thyristor(EST) withl trench gate electrode is proposed for improving snap-back effect which leads to a lot of problems in device applications. The parasitic thyristor which is inherent in the conventional EST is completely eliminated in this structure, allowing higher maximum controllable current densities for ESTs. The dual trench gate allows homogenous current distribution in the EST and preserves the unique feature of the gate controlled current saturation of the thyristor current. The characteristics of the 1700 V forward blocking EST obtained from two-dimensional numerical simulations (MEDICI) is described and compared with that of a conventional EST. we carried out layout, design and process of EST devices.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.104.3-104
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• 2001

This paper develops a control approach to generic formation tasks of multiple mobile robots with inaccurate sensor information. Inaccurate sensor information means that all the robots have only local sensors which cannot accurately measure absolute distances and directions of objects. The control logic is developed considering generic situations in order to adapt to increasing number of robots which participate in the formation. Petri nets are used for modeling and design of the control logic, which can visualize the control models and make it easy to check the states of each robot. Physically homogenous mobile robots are designed and built to evaluate the developed logic. Each robot is equipped with eighteen infrared sensors and a UHF transceiver module. The developed control ...

• International Journal of Human Ecology
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• 제8권2호
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• pp.1-16
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• 2007

The authors examined how Korean housewives manage family resources, make decisions, handle pressures, and negotiate the constraints of everyday life in a society that places unrealistic expectations upon them. The authors approached housewives by imagining them as thinking, strategizing, and problem-solving individuals, who are capable of speaking for themselves and making choices within situational and personal limits. Eleven full-time housewives were interviewed on how they experience their marriages, children, families, and society. Their narratives were then analyzed to sort out the strategies the women employed to maintain their identities. The narratives showed women's will and agency as they worked to resolve the contradictions in their daily life, and revealed individual differences within this group of women who are often seen as homogenous.

• 대한기계학회논문집
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• 제14권2호
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• pp.367-375
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• 1990

A data structure representing 3-D objects was designed for the personal computer. It is very simple to be used in the personal computers which have small memory and low speed. A homogeneous transformation for developing 3-D objects was derived. Each developing procedure consists of five transformations : one translational-three rotational-one translational. Developing a solid is a creative work. So the results of developing vary with the order of surfaces to be developed. One method to reduce the length of seam was considered. The programs used in this study were written in Pascal and Assembly and a modeller that generates 3-D primitives was included. This program is an interactive dual-screen system. While all the menus in Korean are displayed at the monochrome monitor, the development figures with projective views are drawn at the color monitor. The program has wide applications for plate works.