• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 추계학술대회
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• pp.735-737
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• 2016

본 논문에서는 SLA 방식의 3D 프린터 사출방식과 사무용 레이저 프린터의 LSU(Laser Scanning Unit)를 융합한 폴리곤 미러 스캐닝 방식의 3D프린터에 대해 핵심이 되는 기능인 기구부 동작에 따른 테스트를 시행하였다. 이러한 테스트는 레이저 동작 및 제어가 가능한지 확인하였으며 아울러 레이저 모듈과 폴리곤 미러를 사용하여 X축에 일정한 점이 출력됨을 확인하였다. 그리고 레이저를 고정된 F-theta 렌즈에 입사한 후 보정된 빔의 출력을 확인하고 보정된 빔을 반사 거울에 맞춰 Z축 상판에 초점이 맞춰지는지를 확인하였다.

• 기술경영경제학회:학술대회논문집
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• 기술경영경제학회 2003년도 제23회 하계학술발표회 논문집
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• pp.108-115
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• 2003

Government R&D Project Management in Korea has had considerable difficulties because of the lack of project monitoring systems and insufficient communication. The National Program for Tera-level Nanodevices (TND Program) is a ten-year R&D program for commercialization in the area of nano technology. Collaboration and communication among the various participants such as business companies, universities, and government R&D institutes are key success factors in this R&D program. TND Program office has developed a Web-based project management system. This system consists of mostly four sub-management functions: (1) Milestones management of all R&D projects; (2) DR (Design Review) management as the mechanism for checking the performance against milestones; (3) Project activity management using the WBS (Work Breakdown Structure); (4) Budget management. Additionally, it also has many R&D supporting functions such as technology information bulletin board, community management, and visual summary of project progress and performance. This system is effective for monitoring research project as well as measuring project performance of the overall research program. This Web-based system has become the useful tool of R&D moving target mechanism and effective communication and collaboration tool. System features and adoption process of the system are also suggested.

• Journal of Photoscience
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• 제9권2호
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• pp.1-4
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• 2002

Hula-twist is a volume-conserving photoisomerization reaction mechanism postulated in 1985 to account for the rapid photoisomerization of the retinyl chromophore in rhodopsin. The requisite stereochemical consequence of simultaneous isomerization of a double bond and an adjacent single bond has recently been demonstrated in isomerization of pre-vitamin D in an organic glass and by many other examples of organic systems already reported in the literature This paper reports the consequence in applying the mechanism to the primary photochemical process of several photosensitive biopigments: bilirubin, photoactive yellow protein, bacteriorhodopsin and rhodopsin. It is shown that the anchored nature of the chromophores must first be taken into consideration.

• 한국신뢰성학회지:신뢰성응용연구
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• 제13권1호
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• pp.65-76
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• 2013

In order to assess the reliability of engine mount for a vehicles, life test model and procedure are developed. By using this method, failure mechanism and life distribution are analyzed. The main results are as follows; i) the main failure mechanism is degradation failure of engine mount rubber by fatigue failure at dynamic load. ii) temperature is a second factor to affect a failure. iii) the life distribution of engine mount module is fitted well to Weibull life distribution and the shape parameter is 18.4 and the accelerated life model of that is fitted well to Arrhenius model.

• Journal of Photoscience
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• 제12권1호
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• pp.51-54
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• 2005

The electronic excitationenergy quenching of 2, 5-diphenyl-1, 3, 4-oxadiazole (PPD) by Carbon tetrachloride ($CCl_4$) in different solvents viz, n-hexane, n-heptane, toluene, benzene, cyclohexane, 1, 4- dioxane has been carried out at room temperature to understand the role of quenching mechanism. The Stern-Volmer plots have been found to be linear. As probability of quenching per encounter 'p' is less than unity, and the activation energy for quenching '$E_a$' is greater than the activation energy of diffusion '$E_d$', it is inferred that the fluorescence quenching mechanism is not due to material diffusion alone.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.209-214
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• 2003

We developed a new type of human-sized BWR (biped walking robot), named KUBIR1 which is driven by the closed-chain type of actuator. A new type of the closed-chain actuator for the robot is developed, which is composed of the four-bar-link mechanism driven by the ball screw which has high strength and high gear ratio. Each leg of the robot is composed of 6 D.O.F joints. For front walking, three pitch joints and one roll joint at the ankle. In addition to this, one yaw joint for direction change, and another roll joint for balancing the body are attached. Also, the robot has two D.O.F joints of each hand and three D.O.F. for eye motion. There are three actuating motors for stereo cameras for eyes. In all, a 18 degree-of-freedom robot was developed. KUBIR1 was designed to walk autonomously by adapting small 90W DC motors as the robot actuators and batteries and controllers are on-boarded. The whole weight for Kubir1 is over 90Kg, and height is 167Cm. In the paper, the performance test of KUBIR1 will be shown.

• 한국생산제조학회지
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• 제26권1호
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• pp.74-81
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• 2017

A crane is typically used as a means to lift and load equipment or materials. A surface vessel uses a towed object for underwater activity. Such a mechanism for dropping and lifting of equipment is necessary, and is called an overboarding unit. The present study is focused on the overboarding unit used for a crane structure. This paper deals with new overboarding mechanism design and GA-based $MATLAB^{(R)}$ optimization. By using a quadrilateral link mechanism, it is possible to set the constraint function for optimizing the GA method. The optimization with $MATLAB^{(R)}$ is followed by the $SolidWorks^{(R)}$ simulation and verification. When applying the proposed mechanism, the operator is expected to have a big advantage in safety and efficiency of operations. Furthermore, the technology developed in this study will be helpful in similar circumstances and in the proposed mechanism.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.301-301
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• 2011

We present theoretical investigations of the self-assembled growth of one-dimensional (1D) molecular lines directed across the dimer rows on the H-terminated Si(001) surface [1]. Based on density-functional theory calculations, a new growth mechanism of the 1D acetylacetone line is proposed [2], which involves the radical chain reaction initiated at two dangling-bond sites on one side of two adjacent Si dimers. It is also enabled that, if an H-free Si dimer were employed as the initial reaction site, a 1D acetylacetone line can grow along the dimer row. Our findings represent the first insight into the growth of 1D molecular lines not only across but also along the dimer rows on the H-terminated Si(001) surface.

• 대한기계학회논문집
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• 제9권4호
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• pp.528-538
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• 1985

본 논문에서는 crank-rocker 운동에 의해 함수 y=sinx를 만족시키는 3차원 R-S-S-R 함수발생기구를 FDP(Fletcher-Davidon-Powell) 최적화 기법을 응용, 운동학적 으로 무오차점을 고려, 설계하려고 한다. 한편 상기와 같이 최적 설계된 기구의 실 제 운동과 요구된 운동과의 오차분석 및 운동 가능성 여부(mobility check)를 검토하 였으며 FDP 최적화 기법에 필요한 벌칙함수(penalty function)로써 Fiacco-McCormic- krhk Powell의 벌칙함수를 사용하여 그 결과를 비교하였다.

• 한국정보과학회논문지:정보통신
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• 제36권3호
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• pp.256-262
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• 2009

본 논문에서는 IEEE 802.11 링크 계층의 핸드오버 성능을 증가시킬 수 있는 메커니즘을 제시한다. 본 메커니즘은 GPS에 기반한 AP 맵을 참조하여 스캐닝할 채널 수를 줄인다. 또한 모바일 노드와 주변 AP들의 SNR값들을 모니터링 함으로써 주어진 경계 값보다 높은 SNR값을 유지하도록 핸드오버한다. 실험 결과, 본 메커니즘은 6.7%의 통신 단절률을 가지며 평균 16.8 dB의 SNR값을 가진다. 이는 기존의 MadWifi가 사용하는 핸드오버 방식에 비해서는 4.1% 낮은 통신 단절률이며, 26% 높은 평균 SNR값이다.