• Title/Summary/Keyword: science and engineering research operation

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Characteristic of Copper Films on PET Substrate Deposited by Cyclic Operation of RF-magnetron-sputtering Coupled with Continuous Operation of ECR-CVD (연속 ECR-CVD 조업하에 RF-magnetron-sputter의 싸이클조업을 통해 PET위에 올려진 구리박막의 특성)

  • Myung JongYun;Jeon Bupju;Byun Dongjin;Lee Joongkee
    • Korean Journal of Materials Research
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    • v.15 no.7
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    • pp.465-472
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    • 2005
  • Preparation of copper film on PET substrate was carried out by cyclic operation of RF-magnetron­sputtering under continuous operation of ECR-CVD. The purpose of this study is aimed to an increase in deposition rate with keeping excellent adhesion between copper film and PET. In order to optimize the sputtering time under continuous ECR-CVD, cyclic operation concept is employed. By changing parameters of cyclic operation such as split of e and cycle time of A, the characteristics and thickness of the deposited copper film are controlled. As $\theta$ value increase, film thickness could confirm to increase and its surface resistivity value decreases. The highest adhesive strength appears at $\theta=0.33$ and cycle time of 30 min. The uniformity of copper film shows $5\%$ in our experimental range.

High Temperature Size Exclusion Chromatography

  • Cho Hee-Sook;Park Soo-Jin;Ree Moon-Hor;Chang Tai-Hyun;Jung Jin-Chul;Zin Wang-Cheol
    • Macromolecular Research
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    • v.14 no.3
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    • pp.383-386
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    • 2006
  • High temperature size exclusion chromatography (SEC) has been used widely for the characterization of crystalline polymers, for which high temperature operation above the polymer melting temperature is required to dissolve the polymers. However, this high temperature operation has many advantages in SEC separation in addition to merely increasing polymer solubility. At high temperature the eluent viscosity decreases, which in turn decreases the column backpressure and increases the diffusivity of the analytes. Therefore, many reports on the high temperature operation of high performance liquid chromatography (HPLC) have focused on shortening the analysis time and enhancing the resolution. However, the application of high temperature SEC analysis to exploit the merits of high temperature operation is scarce. In this article, therefore, we report on a new apparatus design for high temperature SEC.

Frequency Dependency of Multi-layer OLED Current Density-voltage Shift and Its Application to Digitally-driven AMOLED

  • Kim, Hyunjong;Kim, Suhwan;Hong, Yongtaek
    • Journal of the Optical Society of Korea
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    • v.16 no.2
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    • pp.181-184
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    • 2012
  • We report, for the first time, operation frequency dependence of current density-voltage ($J_{OLED}-V_{OLED}$) shift for multi-layer organic light-emitting diodes (OLEDs). When the OLEDs were electrically stressed for 21 hours with 50% duty voltage pulses at 60, 120, 240, and 360 Hz, the JOLED-VOLED shifts were suppressed by half for 360 Hz operation compared with 60 Hz operation, but with little change in emission efficiencies. This frequency dependent $J_{OLED}-V_{OLED}$ shift is believed to be commonly observed for typical multi-layer OLEDs and can be used to further improve lifetime of digitally-driven active-matrix OLED displays.

A Performance Comparison between Operation Strategies for Idle Vehicles in Automated Guided Vehicle System

  • Kim, Kap-Hwan;Kim, Jae-Yeon
    • Journal of the Korean Operations Research and Management Science Society
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    • v.23 no.2
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    • pp.67-81
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    • 1998
  • An Automated Guided Vehicle System (AGVS) with a unidirectional loop guide path is modeled as a discrete-time stationary Markov chain. It is discussed how to estimate the mean response time, the utilization, and the cycle time of AGV for a delivery order. Three common operation strategies for idle vehicles - central zone positioning rule, circulatory loop positioning rule and point of release positioning rule - are analyzed. These different operation strategies are compared with each other based on the performance measures.

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A New Modified CNP for Autonomous Microgrid Operation Based on Multiagent System

  • Kim, Hak-Man;Wei, Wenpeng;Kinoshita, Tetsuo
    • Journal of Electrical Engineering and Technology
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    • v.6 no.1
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    • pp.139-146
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    • 2011
  • This paper presents a new modified Contract Net Protocol (CNP) for microgrid operation based on multiagent system. The CNP is a widely used protocol for interactions among distributed problem solving. The Contract Net Interaction Protocol of the Foundation for Intelligent Physical Agents (FIPA-CNIP) is a minor modification of the original CNP for multiagent system applications. In this paper, a modified CNP (MCNP) based on the FIPA-CNIP is proposed for more specialized interactions among agents for microgrid operation. A multiagent system is designed and constructed for microgrid operation. A microgrid operation based on the multiagent system is tested to check the functionality of the proposed MCNP.

Using DEA to Analyze the Degree of Global Technology Cooperation at the National Level (DEA를 활용한 국가별 글로벌 기술협력 수준 분석 : OECD 국가를 중심으로)

  • Lee, Mingook;Lee, Sungjoo
    • Journal of the Korean Operations Research and Management Science Society
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    • v.41 no.2
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    • pp.67-80
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    • 2016
  • Under a rapidly changing environment, firms have attempted to co-operate with organizations that possess high technologies to improve their technical capabilities. Most countries have worked towards developing a suitable strategy for international technology co-operation based on the diagnostic results of their technological capabilities and indices. These diagnostic results indicate the level and degree of international technology co-operation that have been developed in academia. However, identifying the overall conditions of international technology co-operation based on existing indices is a difficult task. Hence, to address this problem, indices that can measure diverse perspectives of core technology co-operation activities need to be developed. This research aims to develop a framework for identifying the current state of international technology co-operation in diverse perspectives at the national level. We develop indices based on relevant literature and formulate an analytical framework for international technology co-operation in diverse perspectives using DEA analysis. The results are expected to contribute to effective technology planning at the national level by diagnosing capabilities for international technology co-operation from diverse perspectives.

Region-Based 3D Image Registration Technique for TKR (전슬관절치환술을 위한 3차원 영역기반 영상정합 기술)

  • Key, J.H.;Seo, D.C.;Park, H.S.;Youn, I.C.;Lee, M.K.;Yoo, S.K.;Choi, K.W.
    • Journal of Biomedical Engineering Research
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    • v.27 no.6
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    • pp.392-401
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    • 2006
  • Image Guided Surgery (IGS) system which has variously tried in medical engineering fields is able to give a surgeon objective information of operation process like decision making and surgical planning. This information is displayed through 3D images which are acquired from image modalities like CT and MRI for pre-operation. The technique of image registration is necessary to construct IGS system. Image registration means that 3D model and the object operated by a surgeon are matched on the common frame. Major techniques of registration in IGS system have been used by recognizing fiducial markers placed on the object. However, this method has been criticized due to additional trauma, its invasive protocol inserting fiducial markers in patient's bone and generating noise data when 2D slice images are acquired by image modality because many markers are made of metal. Therefore, this paper developed shape-based registration technique to improve the limitation of fiducial marker based IGS system. Iterative Closest Points (ICP) algorithm was used to match corresponding points and quaternion based rotation and translation transformation using closed form solution applied to find the optimized cost function of transformation. we assumed that this algorithm were used in Total Knee replacement (TKR) operation. Accordingly, we have developed region-based 3D registration technique based on anatomical landmarks and this registration algorithm was evaluated in a femur model. It was found that region-based algorithm can improve the accuracy in 3D registration.