• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2006.05a
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• pp.314-317
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• 2006

Electroformed part is widely used in modem manufacturing industries, especially semi-conductor division. It is basically a specialized form of electroplating. So, it has very similar parameters with electroplating. The object of this study is development of the fine metal mask by electroforming process. In this paper considered two parameters. The first is relationship of UV exposure and soft baking time. The other one is thickness uniformity of electroformed parts by distance of between electrodes. This paper presents the fabrication method of fine metal mask by electroforming process.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.1025-1026
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• 2008

This paper describes a monocular PSD-based motion capture sensor to employ with commercial video game systems such as Microsoft's XBOX and Sony's Playstation II. The system includes a PSD(Position Sensitive Detector) and active infrared (IR) LED markers that are placed on the object to be tracked. The micro-controller calculates the 3D position of the markers using only the measured intensity and the 2D position on the PSD. A series of experiments were performed to evaluate the performance of our prototype system. From the experimental results we see that the proposed system has the advantages of the compact size, the low cost, the easy installation, and the high frame rates to be suitable for high speed motion tracking in games.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.12
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• pp.2535-2540
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• 2002

ESPI is a noncontact, nondestructive and relatively fast inspection method. For these reasons ESPI is being applied as a valuable tool in the nondestructive evaluation of structural components. Phase shifting ESPI is used more effectively than the traditional ESPI because spatial resolution of small object displacements are improved and numerical phase values are obtained for all pixels in the image. Consequently the quantitative measurement of deformation is possible. ESPI fringe patterns are contaminated with high levels of speckle noise. Therefore the phase image is to be smoothed to remove the noise and obtain a better signal-to-noise ratio. In this study, smoothing is done by phase shifting convolution to avoid smoothing errors close to the 2$\pi$ phase ambiguities in the deformation phase image, and median filter is used as a smoothing filter.

• Korean Journal of Optics and Photonics
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• v.5 no.3
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• pp.364-371
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• 1994

Real-time MTF measuring system for testing microlens arrays with a linear CCD array is developed. The spread function of slit image that is relayed and magnified by a microscopic object lens can be measured at several times in a second. The signal uniformity and MTF of CCD is also calibrated. The experimental result of micro lens arrays developed for contact image sensor is presented.sented.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1823-1824
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• 2008

We propose a remote controlled robot manipulator using force feedback joystick. User can control easily 5 d.o.f robot manipulator in 3 demensional space using general joystick. A force sensor attached in developed gripper sends signal to main robot controller so as to know gripper grasp the object. The signal also sent to user through force feedback joystick. We designed a dexterous 5 d.o.f robot manipulator analysis the kinematics and inverse kinematics. The robot was simply developed using serial RC motor. As a main robot controller, we use 32bit MPU(AT91SAM7256) and micro C/OS. To show the validity of our developed robot, a several experiments were demonstrated.

• Journal of the Korean Professional Engineers Association
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• v.15 no.3
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• pp.37-48
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• 1982

A comprehensive plan for provincial development which has been establishing and is about to be completed in 1982, has for its object that concretely develop the undertaking of the second comprehensive Program for land development under the Multiple Purpose Development of the Land Act. The limitations of the establishing tile plan which is subordinated to the Program for land development are, firstly of a difficulty of accepting upper and related plans, secondly, of limit and range of time, space and contents, and thirdly, of validity of the plan in practice. There fore, in order to solve the problems the plan firstly, has to introduce 〃the principle of composition and resolution of forces〃 into approaching to the acceptance of upper and related plans secondly, has to prefer micro approaching to macro in planning, and thirdly, has to have a flexibility of planning which will be easily changed into reasonable plan according to continuous co-ordinated process with the government authorities and inhabitants.

• International Journal of Precision Engineering and Manufacturing
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• v.6 no.2
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• pp.34-39
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• 2005

The precision stage is an essential device for optic fiber assembly systems, micro machines and semiconductor equipments. A new piezoelectric inchworm type actuator is proposed to implement an actuator-integrated long-stroke linear stage. An in-and-quadrature phase (I/Q) heterodyne interferometer is developed as a feedback sensor of a servo system, and a synchronized counting method is proposed. The proposed measurement system can measure the accurate position of fast moving object with robustness to external sensing noise from actuator vibration. The developed servo stage will be applied to optic fiber device assembly system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.303-303
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• 2004

3차원 실물복제기(RODS)는 3차원 스캐닝, SFFS 및 네트워크 등의 복합기능이 내장된 장치로서 제품개발 및 사무자동화등 다양한 분야에 적용 가능한 장비이다. 또한, 기존의 각각 독립된 시스템인 3D스캐너와 SFFS를 하나의 시스템으로 구성함으로서 제작시간과 업무 효율을 높일 수 있는 차세대 시스템의 일종이다. 실물복제기는 산업용과 오피스용으로 구분되어 질 수 있으며, 본 연구에서 개발하고자 하는 다종 재료용 하이브리드형 SFFS는 다품종 소량생산 환경에 적합한 제품의 제작 방식으로서 기능성 부품을 직접 제작/검증 할 수 있다.(중략)

• Transactions of Materials Processing
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• v.12 no.4
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• pp.388-393
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• 2003

Electrolytic polishing is the anodic dissolution process in the transpassive state. It removes non-metallic inclusions and improves mechanical and corrosion resistance of stainless steel. Electrolytic polishing is normally used to remove a very thin layer of material from the surface of a metal object. An electrolyte of phosphoric acid 50% in vol., sulfuric acid 20% in vol. and distilled water 30% in vol. has been used in this study. In the low current density region, there can be found plateau region and material removal process and leveling process occur successively. In this study, an electrochemical polishing process using pulse current is adopted as a new electrochemical polishing process. In electrochemical machining processes, it has been found that pulse electrochemical processes provide an attractive alternative to the electrochemical processes using continuous current. Hence, this study will discuss the electrochemical polishing processes in low current density region and pulse electrochemical polishing.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.235-236
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• 2015

Microlensing can be seen as a version of strong gravitation lensing where the separation angle of the image formed by light deflection by a massive object is too small to be seen by a ground based optical telescope. As a result, what can be observed is the change in light intensity as function of time; the light curve. Conventionally, the intensity of the source is expressed in magnitudes, which uses a logarithmic function of the apparent flux, known as the Pogson formulae. In this work, we compare the magnitudes from the Pogson formulae with magnitudes from the Asinh formulae (Lupton et al. 1999). We found for small fluxes, Asinh magnitudes give smaller deviations, about 0.01 magnitudes smalller than Pogson magnitudes. This result is expected to give significant improvement in detection level of microlensing light curves.