• Applied Science and Convergence Technology
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• v.27 no.3
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• pp.47-51
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• 2018

We fabricated an anode-type ion beam source and studied its driving characteristics of the initial extraction of ions using two driving mechanisms: a diffusion phenomenon and a charge repulsion phenomenon. For specimen exposed to the ion beam in two methods, the surface impurity element was investigated by using X-ray photoelectron spectroscopy. Upon Ar gas injection for plasma generation the ion beam source was operated for 48 hours. We found a Fe 2p peak 5.4 at. % in the initial ions by the diffusion mechanism while no indication of Fe in the ions released in the charge repulsion mechanism. As for a long operation of 200 min, the temperature of ion beam sources was measured to increase at the rate of ${\sim}0.1^{\circ}C/min$ and kept at the initial value of $27^{\circ}C$ for driving by diffusion and charge repulsion mechanism, respectively. In this study, we confirmed that the ion beam source driven by the charge repulsion mechanism was very efficient for a long operation as proved by little electrode damage and thermal stability.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.2
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• pp.107-113
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• 2006

The torsion beam axle type is widely used in the rear suspension for small passenger cars due to low cost, good performance, etc. To develop the torsion beam axle, it is necessary to estimate the characteristics of rear suspension from the design process. The characteristics estimation of the torsion beam axle is performed using FEM, dynamic simulation and is verified the real test. In this study, the natural frequency and roll stiffness of the torsion beam axle were measured by FEM, and the reliability of the FE model was evaluated according to the comparison of test data. This study presents a unique method for the finite element modeling and analysis of the torsion beam axle. The results of the FEA were verified using test data.

• Proceedings of the Optical Society of Korea Conference
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• 2009.02a
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• pp.449-450
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• 2009

The spatial coherence and propagation property of laser beam propagating through several optical components were studied experimentally by using the measurement of Wigner distribution function. It is shown experimentally that the Wigner function measurement yields total degree of coherence, beam quality parameter, and the near and the far field information of the propagating beam. More complete characterization of the laser beam was achieved by applying the Schmidt mode decomposition to the Wigner distribution function, spatial coherence function and directional coherence function. Fine details of coherence property are understood by the characteristics of the contributing eigenmodes.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.8
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• pp.726-730
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• 2002

Electro-optical (EO) performances of the ion beam (IB) aligned twisted-nematic (TN)-liquid crystal display (LCD) with ion beam exposure on the new diamond-like carbon (DLC) thin film surface were investigated. A good voltage-transmittance (V-T) curve of the ion beam aligned TN-LCD with oblique ion beam exposure on the DLC thin film surface for 1 min was observed. Also, the fast response time of the ion beam aligned TN-LCD with oblique ion beam exposure on the DLC thin film surface for 1 min can be achieved. Finally, the residual DC voltage of the ion beam aligned TN-LCD on the DLC thin film surface is almost the same as that of the rubbing aligned TN-LCD on a polyimide (Pl) surface.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.5
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• pp.146-153
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• 2004

Torsion beam rear suspension has been widely adopted to the rear suspension of vehicle by reason of simple structure and cost competitiveness. Since the kinematic characteristics of torsion beam rear suspension are determined by elastic behavior of torsion beam, quasi-static analysis based on finite element modeling of torsion beam has been conducted to obtain the kinematic parameters of torsion beam rear suspension. In this paper, simple kinematic equations with rear geometric parameters are derived to predict the kinematic behavior of torsion beam rear suspension. The suspension design parameters such as roll center height, roll stiffness, roll steer and roll camber can be easily obtained with the kinematic equations. The suggested kinematic equations are validated from comparison with the test results and solution offered by ADAMS. The suspension design parameters varied with the position of torsion beam are discussed.

• Journal of Radiation Industry
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• v.8 no.1
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• pp.59-63
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• 2014

Proton Induced X-ray Emission (PIXE) is a MeV ion beam analysis method for use with particle accelerators. PIXE uses low-energy charged particles as an excitation mechanism to generate characteristic x-ray emission from each element in a target. In PIXE analysis, the beam current used is from a few nA to several tens of nA. Chosun University (Cyclotron Research Center) designed a $50{\mu}A$ beam line from the 13 MeV cyclotron for use with a PIXE analysis system, as well as performing beam transport line optimization research. In this study, the beam line operation conditions for the optimization process of beam transport and beam characteristics are shown.

• Structural Engineering and Mechanics
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• v.7 no.4
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• pp.361-375
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• 1999

This paper presents an analytic method of examining the out-of-plane vibration of continuous curved beam on periodical supports. The orthogonality of two distinct sets of mode shape functions is derived. The forced vibration of beam due to moving loads is examined. Two types of moving loads, which are concentrated load and uniformly distributed load, are considered. The response characteristics of beam induced by these loads are investigated as well.

• Proceedings of the Optical Society of Korea Conference
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• 1990.02a
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• pp.69-72
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• 1990

For the effective heat transfering in Lser Diodes, Beam-Lead structure were introduced which is applicable to hybrid Optoelectronic Integrated Circuits. A 5-layer planar structure Laser Diode is fabricated and Beam-Lead is made by Au plating. And carrier was made by etching Si substrate and LD was mounted on a carrier. The thermal resistance was measured and we could certain that Beam-Lead structure behaves well as a heat sink.

• Proceedings of the Korean Vacuum Society Conference
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• 2003.08a
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• pp.215-215
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• 2003

• Proceedings of the Korean Vacuum Society Conference
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• 2004.02a
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• pp.138-138
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• 2004