• 제어로봇시스템학회논문지
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• 제3권2호
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• pp.187-196
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• 1997

This paper presents a semi-automatic methodology to synthesize executable digital controller saftware in a multi-loop control system. A digital controller is described by a task graph and end-to-end timing requirements. A task graph denotes the software structure of the controller, and the end-to-end requirements establish timing relationships between external inputs and outputs. Our approach translates the end-to-end requirements into a set of task attributes such as task periods and deadlines using nonlinear optimization techniques. Such attributes are essential for control engineers to implement control programs and schedule them in a control system with limited resources. In current engineering practice, human programmers manually derive those attributes in an ad hoc manner: they often resort to radical over-sampling to safely guarantee the given timing requirements, and thus render the resultant system poorly utilized. After task-specific attributes are derived, the tasks are scheduled on a single CPU and the compiled kernel is synthesized. We illustrate this process with a non-trivial servo motor control system.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.1499-1502
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• 2008

This paper proposes an efficient data compression for the conventional method of reducing EMI in a 10 bit LCD timing controller (TCON). In addition, we develop a new method to reduce EMI in a LCD TCON through repeated data on adjacent blocks. The novel technique reduced EMI by 10 dB for a 52" FHD 10it LCD TV.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1791-1794
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• 2006

For system-on-glass (SoG) with low-temperature poly-silicon (LTPS) thin film transistor (TFT), a new system interface architecture and timing controller are developed. With the newly developed system interface architecture, line memory can be eliminated which would take large area of SoG display panel. The system interface and timing controller are targeted for the application for 6-bit gray scale, 60-frames/s qVGA format.

• 한국전자통신학회논문지
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• 제8권2호
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• pp.279-284
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• 2013

본 논문에서는 경제적이고, 채널 확장성이 용이하며, 다양한 성능시험에 대응이 가능한 솔레노이드 타입의 인젝터 컨트롤러를 연구 개발하고 그 성능을 평가하였다. 개발된 컨트롤러는 임베디드 시스템에 기반을 두고 있으며, 인젝터에서 고압으로 분사되는 연료의 분사 타이밍 및 분사량에 대한 정밀제어는 물론 솔레노이드의 전기적인 특성을 측정하여 인젝터의 성능평가도 가능하다. 또한, 부가적으로 인젝터의 분무 형태를 정밀하게 촬영할 수 있는 광원과 초고속 카메라의 정밀시간제어도 동시에 가능하도록 하였다.

• 한국안전학회지
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• 제10권4호
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• pp.22-35
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• 1995

In this paper, an electronic control unit is developed using 16bit microcomputer for automobile engine. This system incorporate AFS(Air Flow Sensor) of Hot Wire type, DIS(Direct Ignition System), ISC(Idle Speed Control) system, CAS(Cranke Angle Sensor) and other peripheral device. This system includes hardware and software to facilitate precision control of both fuel injection and ignition timing. Especially, this controller consists of position signal(180 teeth) and 4 REF signals. Present system has maximum $720^{\circ}CA$ delay. But this system has maximum $180^{\circ}CA$. Thus, this system is able to precision control both fuel injection and ignition timing.

• 제어로봇시스템학회논문지
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• 제22권8호
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• pp.671-677
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• 2016

A Controller Area Network (CAN) is a serial communication protocol that is highly reliable and efficient in many aspects, such as wiring cost and space, system flexibility, and network maintenance. Therefore, it is chosen for the communication protocol between a single chip controller based on Field Programmable Gate Array (FPGA) and peripheral devices. In this paper, the design and implementation of CAN IP, which is written in VHSIC Hardware Description Language (VHDL), is presented. The implemented CAN IP is based on the CAN 2.0A specification. The CAN IP consists of three processes: clock generator, bit timing, and bit streaming. The clock generator process generates a time quantum clock. The bit timing process does synchronization, receives bits from the Rx port, and transmits bits to the Tx port. The bit streaming process generates a bit stream, which is made from a message received from a micro controller subsystem, receives a bit stream from the bit timing process, and handles errors depending on the state of the CAN node and CAN message fields. The implemented CAN IP is synthesized and downloaded into SmartFusion FPGA. Simulations using ModelSim and chip test results show that the implemented CAN IP conforms to the CAN 2.0A specification.

• Journal of Positioning, Navigation, and Timing
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• 제2권1호
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• pp.75-80
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• 2013

This article presents the design of long range navigation (LORAN)-disciplined oscillator (LDO), employing the timing information of the LORAN system, which was developed as a backup system that corrects the vulnerability of the global positioning system (GPS)-based timing information utilization. The LDO designed on the basis of hardware generates a timing source synchronized with reference to the timing information of the LORAN-C receiver. As for the LDO-based timing information measurement, the Kalman filter was applied to estimate the measurement of which variance was minimized so that the stability performance could be improved. The oven-controlled crystal oscillator (OCXO) was employed as the local oscillator of the LDO. The controller was operated by digital proportional-integral-derivative (PID) controlling method. The LDO performance evaluation environment that takes into account the additional secondary factor (ASF) of the LORAN signals allows for the relative ASF observation and data collection using the coordinated universal time (UTC). The collected observation data are used to analyze the effect of ASF on propagation delay. The LDO stability performance was presented by the results of the LDO frequency measurements from which the ASF was excluded.

• Journal of Advanced Marine Engineering and Technology
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• 제27권1호
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• pp.117-123
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• 2003

In a bi-fuel engine using gasoline and LPG fuel, with the current ignition timing for gasoline being used, the effective performance could not be taken in LPG fuel supply mode. The ignition timing in LPG fuel mode must be advanced much more than that of gasoline mode for the compensation of its lower flame speed, due to engine torque drop. This study aims to develop the control system for ignition spark timing conversion which is composed of hardwares and control algorithm for gasoline/LPG engine. We propose the control system which can advance the ignition spark timing in LPG fuel mode more than used in gasoline fuel mode. The advance of ignition timing is achieved by change of the ignition dwell time of coil igniter. The engine torque and F/E(Fuel-Economy) in LPG fuel mode are measured to evaluate the difference of engine performance between before and alter changing ignition spark timings. The engine torque and F/E are increased respectively, which proves the developed control system is effective so much for gasoline and LPG bi-fuel engine.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (C)
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• pp.515-517
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• 2003

In this paper we examine the effects of the required portions of guard timing spaces in a MAC frame of ETSI BRAN HIPERLAN/2 system such as inter-mobile guard timing space in UL(Up Link) duration, inter-RCH(Random CHannel) guard timing space, sector switch guard timing space. In particular, we calculate the number of OFDM(Orthogonal Frequency Division Multiplexing) symbols required for these guard timing spaces in a MAC frame. We them evaluate the throughput of HIPERLAN/2 system as we vary parameter such as the guard time values defined in [2], the number of DLCCs(Data Link Control Connections), and the number of RCHs. Finally we show by numerical results that the portions for the 새심 summation of required guard timing spaces in a MAC frame are not negligible, and that they should be properly considered when trying to evaluate the performance of MAC protocol of HIPERLAN/2 system and also when determining the number of RCHs as well as the number of DLCCs in UL PDU trains at an AP/CC(Access Point/Central Controller).

• 한국기계기술학회지
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• 제13권3호
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• pp.39-47
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• 2011

In a bi-fuel engine using gasoline and LPG fuel, with the current ignition timing for gasoline being used, the optimum performance could not be taken in LPG fuel supply mode. The ignition timing in LPG fuel mode must be advanced much more than that of gasoline mode for the compensation of its higher ignition temperature. The purpose of this study is to investigate how the ignition spark timing conversion influences the engine performance of LPG/Gasoline Bi-Fuel engine. In order to investigate the engine performance during combustion, engine performance are sampled by data acquisition system, for example cylinder pressure, pressure rise rate and heat release rate, while change of the rpm(1500, 2000, 2500) and the ignition timing advance($5^{\circ}$, $10^{\circ}$, $15^{\circ}$, $20^{\circ}$). As the result, between 1500rpm, 2000rpm and 2500rpm, the cylinder pressure and pressure rise rate was increased when the spark ignition was advanced but pressure rise rate at $20^{\circ}$ was smaller value.