• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1826-1827
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• 2011

발전소 제어시스템은 여러개의 제어루프가 있으면 이중 가장 중요한 것은 Unit master control(UMC)와 Boiler master control(BMC)이다. 전력거래소에서 발전기 출력 증발/감발 요구에 의해 가장먼저 BMC가 콘트롤 되어야 하고, 이어서 터빈 컨트롤이 추종하고 있기 때문이다. ABB P-14 제어시스템의 UMC의 각종기능과 구성에 대해 분석한 내용을 논하고자 한다.

• Journal of Animal Science and Technology
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• v.46 no.2
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• pp.251-260
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• 2004

The feasibility and stability of ORP, pH(mV) and DO as a real-time control parameter for SBR process were evaluated in this study. During operation, NBP(nitrogen break point) and NKP(nitrate knee point), which reveal the biological and chemical changes of pollutants, were clearly observed on ORP and pH(mV)-time profiles, and those control points were easily detected by tracking the moving slope changes(MSC). However, when balance of aeration rate to loading rate, or to OUR(oxygen uptake rate), was not optimally maintained, either false NBP was occurred on ORP and DO curves before the appearance of real NBP or specific NBP feature was disappeared on ORP curve. Under that condition, however, very distinct NBP was found on pH(mV)-time profile, and stable detection of that point was feasible by tracking MSC. These results might mean that pH(mV) is superior real-time control parameter for aerobic process than ORP and DO. Meanwhile, as a real-time control parameter for anoxic process, ORP was very stable and more useful parameter than others. Based on these results, a stable real-time control of process can be achieved by using the ORP and pH(mv) parameters in combination rather than using separately. A complete removal of pollutants could be always ensured with this real-time control technology, despite the variations of wastewater and operation condition, as well as an optimization of treatment time and capacity could be feasible.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.3
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• pp.145-151
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• 2004

In this paper, a pressure control type ratio control valve(RCV) is designed for a metal belt CVT. Steady state and transient characteristics of the pressure control CVT are investigated by simulations and experiments. In addition, P-line is proposed to predict the shift performance. It is found that the bigger the pressure margin, the faster the shift response. It is expected that the P-line can be used in design of the RCV to meet the desired shift performance.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10a
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• pp.476-481
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• 1988

In this paper a pH process of a weak acid with a strong base is modeled into a bilinear form, and a self-tuning pH control algorithm which is robust against initial values of solution and disturbances is presented. The control algorithm employs the recursive least square method for the parameter estimation and the generalised minimum variance criterion as the objective function. The computer simulation shows that the tracking of desired pH values is obtained in satisfactory manner regardless of the initial values chosen for the process.

• Journal of Bio-Environment Control
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• v.8 no.3
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• pp.152-163
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• 1999

It is required to analyze the controlled response of air temperature in greenhouse according to control techniques for precise control. In this study, a mathematical model was established for air heating of greenhouse with hot-water heating system The parameters of the model were decided by regression analysis using reference data measured at the greenhouse being heated In the simulation for the digital control of air temperature in the greenhouse, the mathematical model to evaluate the control performances was used. Tested control methods were ON-OFF contpol, p control, rl control and PID control. The mathematical model represented by inside air temperature ( T$_{i}$), hot-water temperature (T$_{w}$) in heating pipe and outside air temperature (T$_{o}$) was expressed as a following discrete time equation ; T$_{i}$($textsc{k}$＋1)＝ 0.851.T$_{i}$($textsc{k}$)＋0.055.T$_{w}$($textsc{k}$)＋0.094.T$_{o}$($textsc{k}$) Control simulations for various control methods showed the settling time, the overshoot and the steady state nor as follows; infinite time, 3.5$0^{\circ}C$, 3.5$0^{\circ}C$ for ON-OFF control : 30min 2.37$^{\circ}C$, 0.51$^{\circ}C$ for P control; 21min, 0.0$0^{\circ}C$, 0.23$^{\circ}C$ for PI control; 18min 0.0$0^{\circ}C$, 0.23$^{\circ}C$ for PID control, respectively. PI and PID controls appeared to be optimal control methods. There was no effect of differential gain on the heating process but much effect of integral gain on it.on it.

• Journal of the Korea Society of Computer and Information
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• v.14 no.12
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• pp.25-32
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• 2009

This paper proposes the construction of intelligent home network system using Power Line Communication(PLC) technique, which allows for UPnP bridge remote control and monitoring based on TCP/IP. Also, the communication for control module inside intelligent home network systems is designed with Simple Control Protocol (SCP) in which each device is connected to be controlled independently. When new UPnP device is additionally installed in intelligent home network systems, it is monitored through UPnP bridges based on its registered UPnP device information. The device control based on PLC and implementation of each UPnP device are effectively managed by using TCP/IP remote control and it's provided fundamental functions to monitor various device information in the home network.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.1 no.2
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• pp.30-42
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• 2002

UPnP(Universal Plug and Play) is commercial product for the first time in home network middlewares, but it has problem that it has no security standards in UPnP specification. In this paper, we present UPnP security model. It is based on XML Signature of XML Security. It provides UPnP with secure services which are device control message authentication and user access level control. It is independent of UPnP modules and has mobility of secure service modules for non secure ability user part. We conclude this paper with an example of applying UPnP Security model to the UPnP audio device control and an test example.

• Proceedings of the KIPE Conference
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• 2010.07a
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• pp.522-523
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• 2010

BLDC 모터의 속도제어기로 주로 사용되는 PI제어기의 응답성능을 개선하기 위하여 본 논문에서는 PI-P구조를 가지는 새로운 속도 제어기를 제안한다. 제안된 방법은 PI 제어기의 출력과 시스템의 출력의 차에 P 이득을 추가하는 방법이다. 추가된 P 이득으로 인해 기존의 제어기에서 발생되는 오버슈트와 느린 정착시간을 개선 할 수 있다. 제안된 방법의 성능을 확인하기 위해서 Matlab Silmulink를 이용한 모의실험을 통해 제안된 제어기의 유용성를 확인한다.

• 한국HCI학회:학술대회논문집
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• 2006.02a
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• pp.747-752
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• 2006

유비쿼터스 환경에서 사용자는 언제 어디서나 주변에 편재하는 컴퓨팅 장치나 서비스를 활용하여 자신이 필요로 하는 작업을 수행할 수 있다. 이러한 컴퓨팅 장치와 서비스를 제어하기 위한 표준으로서 UPnP(Universal Plug and Play)가 각광을 받고 있다. 하지만, 기존에 개발된 UPnP 장치의 원격 제어 프로그램은 사용자의 상황 정보, 선호도 및 접근 권한에 관계없이 동일한 사용자 인터페이스를 제공하기 때문에 사용자에게 편의를 제공하는데 있어 한계가 있다. 본 논문에서는 이러한 단점을 극복하기 위하여 개발된 개인화 및 상황 인지를 지원하는UPnP 장치 원격 제어 프로그램의 설계 및 구현에 대해 기술한다. 제안된 원격 제어 프로그램은 사용자의 상황, 선호도 및 접근 권한에 따라 사용자 인터페이스(User Interface, UI)가 동적으로 생성되고 재구성된다. 또한 이러한 UI 개발의 편의성을 위하여 UPnP 장치 기술(description)에 따라 UI를 자동으로 생성하는 방법에 대해서도 기술한다.

• Proceedings of the KIPE Conference
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• 2012.11a
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• pp.185-186
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• 2012

본 논문에서는 HVDC C&P(High Voltage Direct Current Control and Protection) 시스템의 네트워크 이중화 방법을 제안한다. 본 논문에서 제안하는 HVDC C&P 시스템 네트워크 이중화 방법은 2개의 이더넷 라인을 제어기에 직접 연결하고, 연결된 라인으로 동시에 정보를 송신하여, 제어기에서 정보를 필터링하여 사용하는 방법을 사용한다. 또한 네트워크 라인의 효과적인 결선 체크를 위해 제어기간 송수신을 통해 네트워크 라인의 결선을 체크하는 방법을 사용한다. 위와 같은 방법은 HVDC C&P 시스템의 네트워크 안정성을 향상시키는 효과를 기대할 수 있다.