• Title/Summary/Keyword: Real - time

Search Result 28,998, Processing Time 0.074 seconds

Preemptive Ethernet Controller to Improve Real-Time Characteristics of IEC 61850 Protocol (IEC 61850 프로토콜의 실시간성 향상을 위한 선점형 이더넷 컨트롤러)

  • Lee, Bum-Yong;Park, Tae-Rim;Park, Jae-Hyun
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.59 no.10
    • /
    • pp.1923-1928
    • /
    • 2010
  • The IEC 61850 protocol proposed for the interoperability between IEDs(intelligent electronic devices) adopts the prioritized switched ethernet as its communication channel because substation bus is utilized to exchange both real-time and non real-time messages. The prioritized switched ethernet uses IEEE 802.1Q/p QoS(Quality of Service) in addition to IEEE 802.3 ethernet to enhance the real-time characteristics. However, IEEE 802.1Q/p QoS has priority-blocking problem that occurs when higher-priority frame transmission request during lower-priority frame transmission. To resolve this problem, this paper proposes P(Preemptive)-Ethernet. P-Ethernet uses the modified IEEE 802.1Q/p frame format and new priority preemption mechanism. This paper also implements P-Ethernet controller using FPGA (Virtex-4) and MicroBlaze processor. From the implementation results, P-Ethernet controller shows a improved latency and jitter of transmission period compare to the normal ethernet controller.

Real-Time Monitoring and Warning System for Slope Movements Using FBG Sensor. (광섬유격자 센서를 활용한 사면거동 실시간 안전 진단 시스템)

  • 장기태;정경선;김성환;박권제;이원효;김경태;강창국;홍성진
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2000.11b
    • /
    • pp.60-76
    • /
    • 2000
  • Early detection in real-time response of slope movements ensures tremendous saving of lives and repair costs from catastrophic disaster Therefore, it is essential to constantly monitor the performance and integrity of slope-stabilizing structures such as Rock bolt, Nail and Pile during or after installation. We developed a novel monitoring system using Fiber Bragg Grating (FBG)sensor. It's advantages are highly sensitivity, small dimension and electro-magnetic immunity. capability of multiplexing, system integrity, remote sensing - these serve real-time health monitoring of the structures. Real-time strain measurement by the signal processing program is shown graphically and it gives a warning sound when the monitored strain state exceeds a given threshold level so that any sign of abnormal disturbance on the spot can be easily perceived.

  • PDF

Information Propagation Neural Networks for Real-time Recognition of Vehicles in bad load system (최악환경의 도로시스템 주행시 장애물의 인식율 위한 정보전파 신경회로망)

  • Kim, Jong-Man;Kim, Won-Sop;Lee, Hai-Ki;Han, Byung-Sung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2003.05b
    • /
    • pp.90-95
    • /
    • 2003
  • For the safety driving of an automobile which is become individual requisites, a new Neural Network algorithm which recognized the load vehicles in real time is proposed. The proposed neural network technique is the real time computation method through the inter-node diffusion. In the network, a node corresponds to a state in the quantized input space. Each node is composed of a processing unit and fixed weights from its neighbor nodes as well as its input terminal. The most reliable algorithm derived for real time recognition of vehicles, is a dynamic programming based algorithm based on sequence matching techniques that would process the data as it arrives and could therefore provide continuously updated neighbor information estimates. Through several simulation experiments, real time reconstruction of the nonlinear image information is processed. 1-D LIPN hardware has been composed and various experiments with static and dynamic signals have been implemented.

  • PDF

On Improving the Object-Oriented Method for Real-Time System by Applying the SE Process (SE프로세스를 통한 객체지향 실시간시스템 개발 방법론의 개선에 관한 연구)

  • Lee, Byoung Gil;Lee, Jae Chon
    • Journal of the Korean Society of Systems Engineering
    • /
    • v.2 no.2
    • /
    • pp.21-26
    • /
    • 2006
  • In modern systems technology, increasingly more systems are anticipated to operate in real-time environment. These systems are usually complex to implement since it is not easy to satisfy the real-time requirement for both hardware and software components simultaneously. In this paper, we first review an object-oriented development process that was proposed earlier for software-intensive real-time system using the Unified Modeling Language (UML). We then study how to improve the problems that the UML approach might have. Applying the systems engineering(SE) process yields useful results which include : 1) an improved requirements management over the whole system life-cycle ; 2) a detailed scenario on how to carry out the SE process ; and 3) a conversion process from the text-based requirements to the UML-based graphic ones.

  • PDF

An Event-Driven Real-Time OCL and Its Application (이벤트 위주의 실시간 OCL과 그 응용)

  • Choi, Sung-Woon;Lee, Young-Whan
    • Journal of KIISE:Software and Applications
    • /
    • v.28 no.12
    • /
    • pp.921-929
    • /
    • 2001
  • OCL was used in the UML Semantics document to specify the well-formedness rules of the UML metarmodel. UML was extended to apply it to system developments of several fields, for example real-time UML and web applications with UML. In particular the dependability is important in designing and building hard real-time system. Thus OCL is needed to express real-time UML formally and so it must extended. In this paper, we extend OCL to define event-driven real-time OCL to the development of Nrcl simulator.

  • PDF

LRF-Based Servo System for a Manipulator Grasping Moving Cylinders (움직이는 원통형 물체를 잡는 매니퓰레이터를 위한 레이저 거리계 기반의 서보시스템)

  • Cheon, Hong-Seok;Kim, Byung-Kook
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.14 no.3
    • /
    • pp.263-272
    • /
    • 2008
  • We implemented a real-time servo system for a manipulator based on Laser Range Finder (LRF). and established algorithms for grasping a moving cylinder. We devised a manipulator mechanism and driving hardware based on a system board equipped with Xscale Processor with real-time operating system RTAI on Linux. The manipulator motor driver is connected to the system board via CAN communication link, and LRF is connected via RS-232C. We implemented real-time software including CAN device driver, RS-232C device driver, manipulator trajectory generator, and LRF control software. A typical application experiment for grasping a cylinder with circle motion demonstrated our system's real-time performance.

Development of Realtime EtherCAT Master Library Using INtime

  • Moon, Yong-Seon;Trong, Tuan Anh Vo;Ko, Nak-Yong;Seo, Dong-Jin;Lim, Seung-Woo
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.9 no.2
    • /
    • pp.94-98
    • /
    • 2009
  • This paper proposes an architecture of a real-time EtherCAT master library called RtEML. The controls EtherCAT slaves under EtherCAT protocol in real-time. It provides a simple programming interface which is useful in developing robot application in C/C++ or C#. To achieve deterministic, hard real-time control in Microsoft Windows environment without additional hardware, INtime is used. Since INtime is designed specifically to take advantage of the powerful capabilities of the x86 processor architecture, the proposed RtEML achieves microseconds of real-time performance.

Reliability Based Real-time Slope Stability Assessment

  • Lee, Seung-Rae;Choi, Jung-Chan;Kim, Yun-Ki
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2008.10a
    • /
    • pp.427-435
    • /
    • 2008
  • A reliability based slope stability assessment method is proposed and examined considering the variation of matric suction which is measured by a real time slope monitoring system. Mean value first order reliability method and advanced first order reliability method are used to calculate reliability indices of a slope. The applicability of methods is compared by applying them to the range of matric suctions measured by the real-time monitoring system. Sensitivity analysis is also performed to examine the contribution of random variables to the reliability index of slope. Finally, the proposed method is applied to a model slope. The results show that the reliability index of slope can be used for efficient slope management by quantifying the risk of slope in real time.

  • PDF

Implementation and Performance Evaluation of RTOS-Based Dynamic Controller for Robot Manipulator (Real-Time OS 기반의 로봇 매니퓰레이터 동력학 제어기의 구현 및 성능평가)

  • Kho, Jaw-Won;Lim, Dong-Cheal
    • The Transactions of the Korean Institute of Electrical Engineers P
    • /
    • v.57 no.2
    • /
    • pp.109-114
    • /
    • 2008
  • In this paper, a dynamic learning controller for robot manipulator is implemented using real-time operating system with capabilities of multitasking, intertask communication and synchronization, event-driven, priority-driven scheduling, real-time clock control, etc. The controller hardware system with VME bus and related devices is developed and applied to implement a dynamic learning control scheme for robot manipulator. Real-time performance of the proposed dynamic learning controller is tested and evaluated for tracking of the desired trajectory and compared with the conventional servo controller.

Design for Real-Time Postal Logistics Operational System (실시간 우편물류 운영시스템 설계에 관한 연구)

  • Lee, Ki-Baek;Kim, Wan-Seok;Park, Jong-Heong
    • IE interfaces
    • /
    • v.20 no.4
    • /
    • pp.547-559
    • /
    • 2007
  • In this paper, we design Real-Time Postal Logistics Operational Model and System as a to-be system. Current postal logistics information system, named PostNet, is a basic infra system designed for an end-to-end IT-driven process, from mail acceptance to delivery, linked with internal and external systems. Recent competing circumstances drive demand for more intelligent information system. So we design real-time postal logistics operational system focused on site operations. we analyze postal logistics operation and interview field workers and establish real-time postal logistics operational model to solve operational issues. Finally we suggest system specifications.