• The Korean Journal of Cytopathology
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• v.3 no.1
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• pp.30-36
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• 1992

Pulmonary hamartoma is the most common benign tumor of the lung but rarely encountered in routine cytologic work-up. We recentely experienced a case of fine needle aspiration cytology of pulmonary hamartoma in a 65-year old male patient. The characteristic cytopathologic features were 1) The mesenchymal components with cuboidal epithelial cells in a clean background, 2) The presence of fibromyxoid mesenchymal component composed of fibroblasts in a loose fibrillary stroma, and 3) Antler-liker fibromyxoid cluster having the rimming of epithelial cells which correspond to the epithelial glowing in cleft-like fashion in pulmonary hamartoma.

• Proceedings of the KIEE Conference
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• 2004.10a
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• pp.6-8
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• 2004

Recently, the PM type stepping motor preferred solution for many small electronics position determination devices since it is small in size. Thus, there are glowing demands for permanent magnet(PM) type stepping motor that greater mechanical output, smaller size. This paper deals with a study of the miniaturization of the PM type stepping motor with claw-poles. We introduced the small-sized PM type stopping motor that has new structure and analyzed the magnetic characteristic of it versus general type model using 3-D finite element analysis(FEA).

• Journal of the Korean Society of Groundwater Environment
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• v.7 no.1
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• pp.47-54
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• 2000

The Groundwater has taken a considerable portion of whole water resource and the usage of groundwater has been glowing sharply in recent years in our country. But there have been several problems which include a planless development, a groundwater contamination and so on, because the groundwater management system has built improperly. To solve this problem and control groundwater resources systematically, this study presents improvement measures.

• Journal of the Korean Operations Research and Management Science Society
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• v.27 no.3
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• pp.75-92
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• 2002

This paper is concerned with proposing a new market strategy for the segmented markets of the Internet stock trading. Many companies are providing various services for customers. However, the internet stock trading market is glowing rapidly absorbing a wide variety of customers showing different tastes and demographic information, so that it is necessary for us to investigate specific strategy for the segmented markets. General strategy so far in the Internet stock trading market has been to lower transaction fee according to the market trend. As the advent of rapidly enlarging market, however, more specific strategies need to be suggested for the segmented markets. In this respect, this paper applied a self-organizing map (SOM) to 83 questionnaire data collected from the Internet stock trading market in Korea, and obtained meaningful results.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.215-218
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• 2001

A flame detector responds either to radiant energy visible to the human eye or outside the range of human vision. Such a detector is sensitive to glowing embers, coals, or flames which radiate energy of sufficient intensity and spectral quality to actuate the alarm. An infra-red detectors can respond to the total IR component of the flame alone or in combination with flame flicker in the frequency range of 5 to 30 Hz. A major problem in the use of infrared detectors receiving total IR radiation is the possible interference of solar radiation in the infrared region. When detectors are located in places shielded from the sun, such as vaults. filtering or shielding the unit from the sun's rays is unnecessary. In this study, we proposed method for redue a false alarm with using filtering & sensor technology for distinguish of causes of raise a false alarm and pure flame.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.3
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• pp.214-219
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• 2002

In order to elucidate the crystallographic orientation dependence of electrical properties of carbon (C)-doped GaAs epilayers, C incorporation into GaAs epilayers on high-index GaAs substrates with various crystallographic orientations from (100) to (111)A has been performed by a low pressure metalorganic chemical vapor deposition using C tetrabromide ($CBt_4$) as a C source. The hole concentration of C-doped GaAs epilayers rapidly decreases with a hump at (311)A with increasing the offset angle. Although the growth temperature and the V/III ratio are varied, the crystallographic orientation dependence of hole concentration show a same trend. The above behaviors indicate that the bonding strength of As sites on a glowing surface plays an important role in the C incorporation into the high-index GaAs substrates.

• Proceedings of the KIPE Conference
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• 2012.11a
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• pp.237-238
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• 2012

본 연구는 태양전지용 실리콘 결정 성장용으로 개발된 150[KW] 3,000[A]의 PWM 컨버터 시스템을 개발한 결과이다. 시스템의 구성은 3상 AC-DC 정류변환기, DC-AC 고주파 변환 단상 전파 브리지 PWM 인버터, AC-DC 변압기 중성점을 이용한 단상 전파정류기로 구성되어 있다. 입력 전압은 3상 460[V]이며, 출력은 직류 60[V], 3000[A]로 카본 저항 $2[m{\Omega}]$의 부하에 인버터의 고주파 변압기를 사용하여 스위칭 주파수가 15[KHz]로 PWM제어 방식에 의하여 전력을 제어한다.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.746-752
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• 2001

Design sensitivity analysis for nonlinear structural problems has been emerged in the last decade as a glowing area of engineering research. As a result, theoretical formulations and computational algorithms have already developed for design sensitivity of nonlinear structural problems. There is not enough research for practical nonlinear problems using multi-element, due to difficulties of implementation into FEA. Therefore, nonlinear response analysis for stiffened shell which consists of Mindlin plate and Timoshenko beam, was considered. Specially, it presents the backward-Euler method which is adopted to describe an exact yield state in the stress computation procedure. Then, design sensitivity analysis of nonlinear structures, particularly elasto-perfectly-plastic structure, is developed using direct differentiation method. The accuracy of the developed sensitivity analysis was compared with the central finite difference method. Finally, on the basis of above results, design improvement for stiffened shell is suggested.

• 한국전산유체공학회:학술대회논문집
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• 2004.10a
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• pp.137-139
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• 2004

The monopropellant hydrazine thrusters are widely used for the satellite on-board propulsion system fulfilling various missions in space. They have outstanding features caused by the nearly unlimited restart capability and the very high credibility. The sole monopropellant thruster used at precent in nation is MRE-1 that is a standard component of NASA. It can produce 4.45 N of nominal thrust. Due to the glowing complexity with a satellite mission, the needs for thrusters of the diverse performance are being increased. The numerical simulation could give useful information to develop a new type thruster instead of the experiments performed previously. Therefore it is critical to make a reliable computer code to prepare design change of a thruster. In this paper, the performance analysis and validation of the satellite monopropellant hydrazine thruster currently used is accomplished as the preliminary study to serve valuable data for future design change.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.298-299
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• 2002

WERC (Wakasa Wan Energy Research Center) has started the proton cancer therapy since June 2002. We use Hitachi 3D treatment planning (version 1.6) that can calculate the proton dose distribution by use of the pencil beam algorithm as well as the broad beam algorithm practically fast. This treatment planning software satisfies almost functions required in the proton therapy and includes some advanced techniques such as the 3D region glowing function that can search the target region three-dimensionally based on the CT-values. In this paper, we will introduce this planning system and present our evaluation from point of view of both clinical usage and QA.