• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.9 no.3
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• pp.80-85
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• 2010

In this paper, we present an algorithm for efficient control of backlight LED in order to reduce the power consumption of LCD TV. In addition, a pragmatic implementation method is presented. In conventional local dimming control, backlight LEDs of LCD TV are divided into $M{\times}N$ blocks. And, the proper luminance for each block is computed according to input image and used for dimming control. But, LED light of each block is diffused and affects the neighboring blocks, so that luminance of each block becomes larger than that of intent. In the proposed algorithm, dimming control values are reduced by the amount of quantity affected by the neighboring blocks using light spread function, resulting in additional reduction of power consumption.

• Proceedings of the Korean Information Science Society Conference
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• 2008.06d
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• pp.23-26
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• 2008

본 논문은 Web 환경에서의 사용자의 권한을 검증하고 권한에 대한 이중적인 접근제어 서비스를 제공하는 역할기반의 WAC 시스템의 블럭 설계서를 제안한다. WAC 시스템은 User Interface Block, Access Control Block, Cipher module Block, DataBase로 구성 되며, WAC 시스템의 기능분류모델을 이용한 Block의 세부사항과 WAC 시스템 기본 Bock(Access Control Bock)의 기본 기능 설계 및 사용자 접근제어 기능 설계, DES 기반의 암호 Bock 기능 설계, 인터페이스 설계 대한 WAC 시스템의 전체적인 Block 설계 에 대하여 기술한다.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.313-315
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• 2009

In this thesis, A methodology of system implement for PID controller, PWM logic, HSC logic, Host Communication and external DAC interface are implemented into single FPGA chip is proposed. The implemented system is used to control the speed of DC servo motor. A DATA block transfers set point value(SV) and P, I, D gain parameters to the corresponding Blocks respectively by the Host Communication to Computer. A HSC block generates process value(PV) by a pulse and $90^{\circ}$ shifted pulse from the encoder A PID block makes error(E) signal from the set value and process value and output manufacture value(MV) through the PID controller. In PWM block using the MV from the PID block, drives H-bridge controlling the Motor. Also DAC interface controls the DAC to graph the digital signal such as SV, PV, E, MV in FPGA onto the Oscilloscope.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.575-576
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• 2008

This paper presents a design of a charge pumping circuit for LCD Driver IC. The charge pumping circuit consists of a control block, a VCIOUT generating block, a DDVDH generating block, a VGH/VGL generating block, and VCL generating block. It generates various higher and lower voltage than supply voltage using external control input. Simulation results show that voltages of DDVDH, VGH, VGL, and VCL satisfy the target voltage, and the output DDVDH drives the output current 7mA.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.9
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• pp.545-551
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• 2004

CBTC(Communication Based Train Control) System can improve train operation efficiency by realizing moving block system which makes a continuous train interval control in accordance with the position and speed of train. Adopting radio transmission to make a continuous detection of train position and transmit the control data from the ground to a train, CBTC needs dedicated train operation and control algorithm which should be quite different from the conventional track-circuit-based train control system. This paper provides a train operation display and control algorithm for CBTC system in making train interval control, train route control and train supervision. Signalling pattern diagram is devised to analyze the train interval control mechanism of moving block system, and interlocking logic is devised to represent the train route control mechanism of moving block system. For train supervision, train occupation status on railway are displayed by using the segment which virtually divide the whole railway. The proposed method has been successfully applied to the development of CBTC system for the standardized AGT(automatic guided transit) which is under construction now in Korea, and also can be applied to any other CBTC system.

• Journal of the Korean Wood Science and Technology
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• v.44 no.3
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• pp.315-322
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• 2016

Block-glued glulam is a structural material that can be used as a construction member of a large-section wooden building, which is produced by edgewise bonding of two or more glulam beam elements. The edgewise bonding performance of the block-glued glulam was examined through delamination test and block shear strength test. According to the test results, the block-glued glulam that was manufactured with 1.5 MPa of compressive pressure after applying $500g/m^2$ of Resorcinol adhesive showed the best edgewise bonding performance. The block-glued glulam produced in a good edgewise bonding condition was compared with a control glulam with the same section modulus for bending strength performance. The modulus of elasticity (MOE) in bending was similar to that of the control glulam. The modulus of rupture (MOR) of the block-glued glulam was higher by 27% than that of the control glulam. No interfacial failure or cohesive failure were observed in the edgewise bonding layer.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2726-2730
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• 2011

This paper proposes a CBTC wayside signaling system, which redeems existing track-circuit-based ones by using movement authorities mixed with logical block and moving block. Only one train can be entered into the logical block or the route for existing wayside signaling system. Applying moving block for CBTC system enables the train to get nearer to the preceding one, because its protection mechanism uses train's safe boundary, not fixed block unit. By narrowing the existing route set to switch machine and applying the moving block beyond that area, more than one train can enter into one route area. This paper shows that the efficient train control, i.e. shortening the headway, is possible using the moving block mixed with logical block in wayside signaling system.

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.171-176
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• 2005

This paper presents a novel Intelligent-Welding-Carriage (IWC) for automation of curved block in shipbuilding. The curved block is usually used in both front and back side of the ship. In curved block root gap is big, 1-7 (mm) and inclination, 0-30 (deg). Since available conventional carriage type is limited to use below root gap of 3 (mm), only manual welding is employed in curved block. To adopt an IWC in curved block, it requires control of the welding conditions, i.e., voltage. current, weaving speed, dwell time and travel speed, with respect to root gap and inclination to achieve good welding qualify. In this paper, an IWC is developed for automization of welding operation to accommodate gap and inclination. Kinematics model and dynamics using Lagrangian formulation of the manipulator is introduced. IWC utilizes a database to perform accurate welding. The database is programmed based on numerous experimental test results with respect to gap, inclination, material, travel speed, weaving condition, voltage, and current. Finally, experimental result using PID control is addressed for verifying the trajectory tracking accuracy of end-effector.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2277-2279
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• 2003

This paper presents a new method for finding the Block Pulse series coefficients and deriving the Block Pulse integration operational matrices which are necessary for the control fields using the Block Pulse functions. This paper presents the method for improving the accuracy of the Block Pulse series coefficients and derives the related integration operational matrices by using the Lagrange second order interpolation polynomial and expands that matrix to general form.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.6
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• pp.71-81
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• 2000

This paper describers a look ahead algorithm of PC-NC(personal computer numerical control). The algorithm is based on acceleration/deceleration before interpolation which doesn\`t include a command error and determines a feedrate value at the end point of each block(or start point of each block). The algorithm is represented as following; 1) calculating two maximum arrival feedrates(F$_1$,F$_2$) by an acceleration value, a command feedrate, and the distance of a NC block, 2) getting a tangent feedrate (F$_3$) of the adjacent blocks, 3) choosing a minimum value among these three feedrates, and 4) setting the value to a feedrate of a start point of the next block(or a end point of the previous block). The proposed look ahead algorithm was implemented and tested by using a commercial TROS(real time operation system) on the MS-Windows NT 4.0 in a PC platform. For interfacing to a machine, a counter board, a DAC board and a DIO board were used. The result of the algorithm increased a machining precision and a machining speed in many short blocks.