• Journal of the Korean Society for Precision Engineering
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• v.4 no.4
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• pp.25-35
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• 1987

This paper deals with the design of the digital controller for DC servo motor, and it is implemented for the cartesian coordinate 4 axes manipulator. A design method of the controller is adopted an algorithm using the digital position locked loop(DPLL) method and the linear PID control for the smooth motion. To simplify the hardware configuration of control system, 8279 keyboard/display controller, Z-80 CTC counter and 8255 PPI are used. Therefore the design method to control each motor as real-time is presented. To show effectiveness of the design, the PWM circuit and frequency/voltage converter are applied for the velocity control of robot system. When the proposed controller is applied to the 4-axes manipulator, it reveals that the error probabilities of X, Y and Z axis as 0.033%, 0.023% and 0.028% respectively.

• Proceedings of the KSR Conference
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• 2003.10b
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• pp.311-318
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• 2003

Traffic management means the management of streams of people, vehicle and cargo. Its aim is to help creating an efficient, safe and environmentally friendly transport system. Traffic management can roughly be divided in traffic control and monitoring, traffic information and demand management. The main purpose of this thesis is providing the basis for developing the next generation train traffic management system by comparing domestic and abroad train traffic management system. The composition of this thesis has been discussed in the following order of the comparison of train traffic management system's function, the introduction of Autonomous Decentralized system, the comparison between CTC and ATOS. the comparison between the hierarchy system and Autonomous Decentralized system, the study of introduction plan of Autonomous Decentralized-type train traffic management system and conclusion.

• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2562-2564
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• 2004

This paper addresses a simulation for the Ethernet based data transmission between the CIC(Centralized Traffic Control System) and the SCADA(Supervisory Control and Data Acquisition) system. Fame error rate and throughput are calculated and compared for the two cases that the CTC/SCADA has an extra error control scheme besides the internal CRC32 of the Ethernet and that no extra error control has been done. Simulation program is constructed with the Matlab and the Matlab GUI and then converted into a stand-alone $c^{++}$ program to be used on any non-Matlab environments.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.275-276
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• 2008

IEEE802.16e-based OFDMA system called WiBro is being serviced commercially. In WiBro system, the base station sends downlink(DL)-MAP information to all mobile stations in each cell. The DL-MAP information is repeated six times, modulated by QPSK, and coded by Convolutional Turbo Coding(CTC) with 1/2 code rate [1],[2]. As the number of mobile stations increases, the DL-MAP size also increases. In this paper, We investigate methods of power allocation and interference cancelation to reduce overhead of the DL-MAP.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.3
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• pp.139-143
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• 2014

This paper proposes a simplified DC calculation method for simplified depth coding (SDC) mode of 3D High Efficiency Video Coding (3D-HEVC) to reduce the computational complexity. For the computational complexity reduction, the current reference software of 3D-HEVC employs reference samples sub-sampling method. However, accumulation, branch, and division operations are still utilized and these operations increase computational complexity. The proposed method calculates DC value without those operations. The experimental results show that the proposed method achieves 0.1% coding gain for synthesized views in common test condition (CTC) with the significantly reduced number of computing operations.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.04a
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• pp.107-110
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• 2000

화학 박막 증착용(CVD : Chemical Vapor Deposition) 클러스터 장비는 다양한 공정 경로가 가능하며 물류 흐름이 매우 복잡해질 수 있다. 또한, 공정이 종료된 웨이퍼는 제한 시간 내에 챔버에서 꺼내져야만 한다. 클러스터 장비는 두 개의 팔을 가진 로봇이며, 빈 쪽 팔을 이용하여 공정이 종료된 웨이퍼를 꺼낸 후, 다른 쪽 팔을 이용하여 이전 공정에서 가져온 웨이퍼를 해당 공정에 넣어 주는 스왑(SWAP) 방식으로 운영된다. 이러한 스왑 방식에서는 로봇 작업 순서가 결정되어 진다. 그러나, 로봇의 팔 이외에 임시버퍼가 없고, 각 챔버는 엄격한 체제 시간 제약(Residency Time Constraint)을 가지고 있기 때문에 로봇의 작업 시점의 제어가 필요하다. 본 논문에서는 간단한 Earliest Starting 방식으로 로봇의 작업 시점을 제어한다고 가정했을 때, 스왑 방식을 운용하면서 체제 시간 제약을 만족하는 공정 시간들의 조건을 제시한다. 공정 시간은 엔지니어에 의해 다소 조정이 가능하므로 공정 시간들의 조건은 엔지니어에게 스케줄 가능한 공정 시간을 결정할 수 있도록 지원해 주는 시스템에 활용 가능하다. 또한, 본 논문에서는 FSM(Finite State Machine)을 이용하여 CTC(Cluster Tool Controller) 내부의 실시간 스케줄러 구현 방법을 제안한다.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.1159-1164
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• 2005

현재 철도청이 운용중인 열차운행관리 시스템(Railway Traffic Management System, RTMS)은 서울, 대전, 부산, 순천 그리고 영주 등으로 총 5개 지역본부로 분산되어 있어 업무의 중복을 줄이고, 자동화(Automation)된 열차집중제어장치(Central Traffic Control, CTC)를 구축하기 위해 지역본부를 대전으로 통합하는 프로젝트를 진행중이다. 본 논문은 철도청 사령실 통합 신호설비 구축 프로젝트에 의거하여 열차 경합을 검지 또는 예측하고 운영자에게 최소의 시간 내에 최적의 해소 대책을 제시함을 목적으로 하는 열차 경합 검지 시스템을 구현하는 과정에서 작성되었다. 여기에서는 열차 경합 검지에 대한 개요와 검지 가능한 경합 종류에 대해 기술하고, 실제 구현된 알고리즘의 기본적인 내용, 프로세스의 구성도 및 시뮬레이션 결과를 설명하려고 한다.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.928-931
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• 2007

In answer to the increase of demand for the safety in railroad, the safety activities are tried out. According to 'KORAIL Instruction number 2001-49', the project for developing Integrated Centralized Traffic Control Center has been carried out and the safety activities are guaranteed by documents named 'Safety Plan' and 'Safety Requirements' from this project. However the development system is not enough for the full safety activities. Therefore this paper we describes the relationship of safety activities and development systems and proposes the efficient direction of safety activities.

• IEIE Transactions on Smart Processing and Computing
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• v.3 no.6
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• pp.388-392
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• 2014

This paper proposes an early termination method of a block vector search for fast encoding of high efficiency video coding (HEVC) screen content coding (SCC). In the proposed algorithm, two blocks indicated by two block vector predictors (BVPs) were first employed as an intra block copy (IBC) search. If the sum of absolute difference (SAD) value of the block is less than a threshold defined empirically, an IBC BV search is terminated early. The initial threshold for early termination is derived by statistical analysis and it can be modified adaptively based on a quantization parameter (QP). The proposed algorithm is evaluated on SCM-2.0 under all intra (AI) coding configurations. Experimental results show that the proposed algorithm reduces IBC BV search time by 29.23% on average while the average BD-rate loss is 0.41% under the HEVC SCC common test conditions (CTC).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.5
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• pp.579-589
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• 2018

Data from the two bottom moorings of ADCP (acoustic doppler current profiler), coastal weather station and CTC (conductivity temperature depth) observations for 2001 were analyzed to describe the physical processes associated with upwelling off the southeast coast of Korea. Winds were favorable for upwelling during summer, but were not correlated with currents. Shoaling of isotherms toward the coast due to the baroclinic tilting of the strong East Korean Warm Current (EKWC) provided a favorable background for immediate upwelling-response of surface temperature to southerly winds. This baroclinic effect was supported by a significant inverse coherence between the upper-layer current and bottom temperature near the coast. This upwelling is similar to the Guinea Current upwelling, which is driven by remote forcing (Houghton, 1989). Persistent southward flow was observed below approximately $10^{\circ}C$ isotherm throughout the observation period.