• 한국진공학회지
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• 제8권4B호
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• pp.556-564
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• 1999

The analysis on heat fluxed on and transmission efficiencies by the collimators of neutral beam injection lines in KSTAR tokamak device has been carried out. And a mathematical model describing non-Gaussian beam distribution profile has been established. A neutral beam injection device is composed of 3 separate ion sources and corresponding beam transport lines, which deal with 7.8 MW of beam power, respectively. The divergence angles of ion beam are $1.2^{\circ}$and $0.5^{\circ}$, in vertical and horizontal directions, respectively. The maximum normal heat load on source exit scraper is 9.1 kW/$\textrm{cm}^2$ and net beam transmission efficiency is ~28%. The effect of misalignment of ion source and scrapers on the scraper heat load and beam transmission also has been analyzed.

• 한국레이저가공학회지
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• 제18권3호
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• pp.6-8
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• 2015

Finishing process includes deburring, polishing and edge radiusing. It improves the surface profile of specimen and eliminates the alien substance on surface. Deburring is the elimination process for debris of edges. Polishing lubricates surfaces by rubbing or chemical treatment. There are two types for electron finishing. The one is using pulse beam. The other is using the convergent and scanning electron beam. Pulse type device appropriates the large area process. But it does not control the beam dosage. Scanning type device has advantages for dosage control and edge deburring. We design the convergence and scan type. It has magnetic lenses for convergence and scan device for scanning beam. Magnetic lenses consist of convergent and objective lens. The lenses are designed by the specification(beam size and working distance). In this paper, we evaluate the convergence performance by pattern process. Also, we analysis the results and important factors for process. The important factors for process are beam size, pressure, stage speed and vacuum. These results will be utilized into systematizing pattern shape and the factors.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
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• pp.442-444
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• 1998

We made the beam crosssectional monitor system which was possible to display the ion beam crosssection extracted from accelerator on personal computer monitor. Previous beam profile monitor system could detect the central beam position with limited low beam current, but this developed beam crosssectional monitor system could operate at the relatively higher beam current. In addition we realized the real time data taking system by adopting the VXI system for beam size, central position and crosssection.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.1157-1159
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• 2003

The effect of the scan velocity modulation is studied. The effect of the velocity modulation on the picture image is judged from the intensity profile of the image. The intensity profile is obtained as time integral of moving Gaussian beam. To confirm the applicability of this integral formula, the measurement and simulation data is compared. And by calculating the intensity profile for different amounts of velocity modulation, the optimum modulation displacement that gives the best image quality is obtained. This optimum modulation displacement can be used in designing scan velocity modulation system.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.269-273
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• 2004

The moduled interferometer with waveplates, polarizing beam splitter, etc. for four phase shifted interference patterns was stabilized with the and Fast Fourier Transform (FFT) method was used to investigate the surface profile measurement from the interferenece pattern from Twyman-Green interferometer using a mathcad.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1995년도 추계학술대회논문집; 한국종합전시장, 24 Nov. 1995
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• pp.197-200
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• 1995

Corrugation of railway track can be caused by the various dynamic behavior of travelling wheels and track. In this paper, the coupled vibrations of travelling wheel and railway track are analyzed as the cause of corrugations. To analyze the coupled vibrations, the track supported by the sleepers and the traveling wheel are identified to the elastically supported infinite beam and the spring-mass system which runs at constant speed. The Hertzian contact spring is considered betwen the infinite beam and spring-mass system. The dynamic responses of elastically supported infinite beam and spring-mass system are calculated. The cause and development of rail corrugation are discussed in the view point of contact force fluctuation affected by the elastic supports and the corrugated surface profile of the track. By the obtained results, the possibilities of resonance are checked between the excitation by the corrugated surface profile and the natural frequency of contact spring-moving mass system. It may be thought to a development of railway corrugation.

• Journal of Welding and Joining
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• 제25권3호
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• pp.85-91
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• 2007

The conventional study on the laser surface transformation hardening has been carried out with a beam of the specified shape and uniform power-intensity distribution in order to ensure the uniformity of the hardening depth. Two types of beams - the circular gaussian beam and rectangular beam of the uniform power-intensity distribution were used in this study. we were supposed to optimize the process parameters and to compare the hardening results with two optics respectively. As a result, the hardness distribution of the hardened zone was similar in both cases and the hardened phase by the rectangular beam was denser than that by the circular gaussian beam.

• 한국의학물리학회지:의학물리
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• 제1권1호
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• pp.75-84
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• 1990

We have claculated the absorbed dose distributions in water phantom irradiated by high energy photon beam. PDD (Percent Depth Dose) and Beam Profile can be represented by functions of depths and distances by using one dimensional model model based on transport theory. The parameters on scattering and absorption are evaluated by using non-linear regression process method. The values neeessary for calculation are obtained by simple experiment. The calculated values are in good agreement with the measured values.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.395-398
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• 2002

The spherical aberration and optical integer (f) of the electron gun's main lens in color CRT is obtained, using electron beam trajectory. A spherical aberration is obtained from the relation between the object plane and the image of a beam trajectory. To analyze beam profile, 3rd and 1st order coefficient were obtained and used. It is shown that, in practice, they are applied to electron gun design.

• 한국진공학회지
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• 제20권2호
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• pp.100-105
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• 2011

이온을 Si(100) 기판에 주입할 때 조사량과 에너지, 빔 전류가 면저항에 영향을 미치는 원인을 규명하기 위해 여러 연구자가 행하였던 실험과 동일한 조건으로 Crystal TRIM 프로그램을 이용하여 컴퓨터 시뮬레이션을 실행하였다. 주입한 $As^+$이온의 조사량을 $1{\times}10^{15}/cm^2$로 일정하게 하고 에너지를 5, 10, 15 keV로 변화시켜 계산한 결과 에너지가 커질수록 Rp값은 표면에서 깊어지는 반면에, 표면근방에 축적되는 격자손상은 증가하였다. 20keV의 B+이온을 $5{\times}10^{15}/cm^2$의 동일한 조사량으로 1mA와 7 mA의 빔 전류에 해당하는 값을 이용하여 계산한 결과 빔 전류가 커질수록 표면근방 100 nm 이내에서 격자손상이 증가하였다. 20 keV의 일정한 에너지로 B+이온을 $1{\times}10^{15}$, $3{\times}10^{15}/cm^2$ 조사량과 0.8 mA와 8 mA의 빔 전류로 각각 계산한 결과 조사량이 많아질수록, 빔 전류가 커질수록 표면 근방에 축적되는 격자손상의 양이 증가하였다. 이러한 에너지, 조사량과 빔 전류증가에 의한 시료표면의 격자손상 증가는 시료표면의 면저항을 감소시킨다.