• Title/Summary/Keyword: Real-time network system

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A Study on the Implementation of CAN in the Distributed System of Power Plant (발전설비 분산제어 시스템에서 CAN 구축기술 연구)

  • Kim, Uk-Heon;Hong, Seung-Ho
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.6
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    • pp.760-772
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    • 1999
  • The CAN is a serial communication protocol for distributed real-time control and automation systems. Data generated from field devices in the distributed control of power plant are classified into three categories: real-time event data, real-time control data, non-real-time data. These data share a CAN medium. If the traffic of the CAN protocol is not efficiently controlled, performance requirements of the power plant system could not be satisfied. This paper proposes a bandwidth allocation algorithm that can be applicable to the CAN protocol. The bandwidth allocation algorithm not only satisfies the performance requirements of the real-time systems in the power plant but also fully utilizes the bandwidth of CAN. The bandwidth allocation algorithm introduced in this paper is validated using the integrated discrete-event/continuous-time simulation model which comprises the CAN network and distributed control system of power plant.

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Wireless Sensor Networks based Forest Fire Surveillance System

  • Son, Byung-Rak;Kim, Jung-Gyu
    • Proceedings of the Korea Society of Information Technology Applications Conference
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    • 2005.11a
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    • pp.123-126
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    • 2005
  • Wireless Sensor Networks will revolutionize applications such as environmental monitoring, home automation, and logistics. We developed forest fire surveillance system. In this paper, Considering the fact that in Korea, during November to May, forest fires occur very frequently causing catastrophic damages on the valuable environment, Although exists other forest fire surveillance system such as surveillance camera tower, infrared ray sensor system and satellite system. Preexistence surveillance system can't real-time surveillance, monitoring, database and automatic alarm. But, forest fire surveillance system(FFSS) support above. In this paper, we describes a system development approach for a wireless sensor network based FFSS that is to be used to measure temperature and humidity as well as being fitted with a smoke detector. Such a device can be used as an early warning fire detection system and real-time surveillance in the area of a bush fire or endangered public infrastructure. Once the system has being development, a mesh network topology will be implemented with the chosen sensor node with the aim of developing a sophisticated mesh network.

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A Real-time Multibody Vehicle Dynamics and Control Model for a Virtual Reality Intelligent Vehicle Simulator (가상현실 지능형 차량 시뮬레이터를 위한 실시간 다물체 차량 동역학 및 제어모델)

  • 김성수;손병석;송금정;정상윤
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.4
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    • pp.173-179
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    • 2003
  • In this paper, a real-time multibody vehicle dynamics and control model has been developed for a virtual reality intelligent vehicle simulator. The simulator consists of low PCs for a virtual reality visualization system, vehicle dynamics and control analysis system a control loading system, and a network monitoring system. Virtual environment is created by 3D Studio Max graphic tool and OpenGVS real-time rendering library. A real-time vehicle dynamics and control model consists of a control module based on the sliding mode control for adaptive cruise control and a real-time multibody vehicle dynamics module based on the subsystem synthesis method. To verify the real-time capability of the model, cut-in, cut-out simulations have been carried out.

Design of a Communication Protocol for the Physical Layer of the Digital Control System (디지털제어시스템의 물리계층 통신 프로토콜 설계)

  • Lee, S.W.
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.2419-2422
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    • 2000
  • A distributed real-time system that is being used now is usually divided into three level : higher level, middle level, and lower level. The higher level network is usually called an information network, the middle level is called a control network, and the lower level is called a field network or a divice network. This dissertation suggests and implements a middle level network which is called PICNET-NP (Plant Implementation and Control Network for Nuclear Power Plant). PICNET-NP is based partly on IEEE 802.4 token-passing bus access methed and partly on IEEE 802.3 physical layer. For this purpose a new interface, a physical layer service translater, is introduced. A control network using this method is implemented and applied to a distributed real-time system.

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Design of a Communication Protocol for the Distributed Control System of the Nuclear Power Plants (원자력 발전소 분산제어시스템의 통신 프로토콜 설계)

  • 이성우;윤명현;문홍주;이병윤
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 1999.11a
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    • pp.143-148
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    • 1999
  • A distributed real-time system that is being wed now is usually divided into three level : higher level, middle level, and lower level. The higher level network is usually called an information network, the middle level is called a control network, and the lower level is called a field network or a divice network. This dissertation suggests and implements a middle level network which is called PICNET-NP (Plant Implementation and Control Network for Nuclear Power Plant). PICNET-NP is based partly on IEEE 802.4 token-passing bus access method and partly on IEEE 802.3 physical layer. For this purpose a new interface, a physical layer service translator, is introduced. A control network using this method is implemented and applied to a distributed real-time system.

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Spatio-temporal Analysis using Real-Time Data Processing for Wireless Sensor Networks (무선 센서 네트워크에서 실시간 데이터 처리를 이용한 시공간 분석)

  • Baek, Jeong-Ho;Mun, Young-Chae;Lee, Hong-Ro
    • Journal of KIISE:Computing Practices and Letters
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    • v.16 no.6
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    • pp.688-692
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    • 2010
  • Wireless sensor network system collects and analyzes real-time data that have been requested by the many application nodes. This paper has constructed a sensor network cluster with various elements in the Gunsan City area of Jeollabuk-do, S.korea. The purpose of this paper is to utilize the constructed system in order to illustrate the real-time data in a diagram and analyze it to deduce the change ratio. The resulting analysis contents allow simple data interpretation by illustrating the data in change ratio by time, space, and motional directions. This analytical method will offer great benefit to those users using the wireless sensor network.

Distributed Real Time Simulation Programming with Time and Message Object Oriented in Computer Network Systems

  • Ra , Sang-Dong;Na, Ha-Sun;Kim, Moon-Hwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.1C
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    • pp.157-165
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    • 2004
  • Real-time(RT) object-oriented(OO) distributed computing is a form of RT distributed computing realized with a distributed computer system structured in the form of an object network. Several approached proposed in recent years for extending the conventional object structuring scheme to suit RT applications, are briefly reviewed. Then the approach named the TMO(Time-triggered Message-triggered Object)structuring scheme was formulated with the goal of instigating a quantum productivity jump in the design of distributed time triggered simulation. The TMO scheme is intended to facilitate the pursuit of a new paradigm in designing distributed time triggered simulation which is to realize real-time computing with a common and general design style that does not alienate the main-stream computing industry and yet to allow system engineers to confidently produce certifiable distributed time triggered simulation for safety-critical applications. The TMO structuring scheme is a syntactically simple but semantically powerful extension of the conventional object structuring approached and as such, its support tools can be based on various well-established OO programming languages such as C++ and on ubiquitous commercial RT operating system kernels. The Scheme enables a great reduction of the designers efforts in guaranteeing timely service capabilities of application systems. Start after striking space key 2 times.

A Study on Real-Time Defect Detection System Using CNN Algorithm During Scaffold 3D Printing (CNN 알고리즘을 이용한 인공지지체의 3D프린터 출력 시 실시간 출력 불량 탐지 시스템에 관한 연구)

  • Lee, Song Yeon;Huh, Yong Jeong
    • Journal of the Semiconductor & Display Technology
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    • v.20 no.3
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    • pp.125-130
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    • 2021
  • Scaffold is used to produce bio sensor. Scaffold is required high dimensional accuracy. 3D printer is used to manufacture scaffold. 3D printer can't detect defect during printing. Defect detection is very important in scaffold printing. Real-time defect detection is very necessary on industry. In this paper, we proposed the method for real-time scaffold defect detection. Real-time defect detection model is produced using CNN(Convolution Neural Network) algorithm. Performance of the proposed model has been verified through evaluation. Real-time defect detection system are manufactured on hardware. Experiments were conducted to detect scaffold defects in real-time. As result of verification, the defect detection system detected scaffold defect well in real-time.

Architecture Design for Maritime Centimeter-Level GNSS Augmentation Service and Initial Experimental Results on Testbed Network

  • Kim, Gimin;Jeon, TaeHyeong;Song, Jaeyoung;Park, Sul Gee;Park, Sang Hyun
    • Journal of Positioning, Navigation, and Timing
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    • v.11 no.4
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    • pp.269-277
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    • 2022
  • In this paper, we overview the system development status of the national maritime precise point positioning-real-time kinematic (PPP-RTK) service in Korea, also known as the Precise POsitioning and INTegrity monitoring (POINT) system. The development of the POINT service began in 2020, and the open service is scheduled to start in 2025. The architecture of the POINT system is composed of three provider-side facilities-a reference station, monitoring station, and central control station-and one user-side receiver platform. Here, we propose the detailed functionality of each component considering unidirectional broadcasting of augmentation data. To meet the centimeter-level user positioning accuracy in maritime coverage, new reference stations were installed. Each reference station operates with a dual receiver and dual antenna to reduce the risk of malfunctioning, which can deteriorate the availability of the POINT service. The initial experimental results of a testbed from corrections generated from the testbed network, including newly installed reference stations, are presented. The results show that the horizontal and vertical accuracies satisfy 2.63 cm and 5.77 cm, respectively. For the purpose of (near) real-time broadcasting of POINT correction data, we designed a correction message format including satellite orbit, satellite clock, satellite signal bias, ionospheric delay, tropospheric delay, and coordinate transformation parameters. The (near) real-time experimental setup utilizing (near) real-time processing of testbed network data and the designed message format are proposed for future testing and verification of the system.

A Co-simulation Toolbox for Distributed Real-Time Control System (분산형 실시간 제어시스템을 위한 연계 모의실험에 관한 연구)

  • 김승훈;이우택;선우명호
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.1
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    • pp.166-171
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    • 2003
  • This paper presents the algorithms and Matlab Toolbox for co-simulation of distributed real-time control system based on OSEK-OS and CAN protocol. This toolbox enables the developers to analyze the timing uncertainty, which is caused by resource sharing including shared memories and networks, and to take the timing uncertainty into consideration in the early design phase. Furthermore, this toolbox helps the developers to model the behaviors of a control system by providing graphical user interface for objects of OSEK-OS and CAN. To prove the feasibility of this toolbox, a vehicle body network system is modeled with this toolbox, and the timing uncertainties are analyzed.