• Title/Summary/Keyword: real-time mechanism

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AUTOSAR : Deadline-Compliant Scheduling Method Applicable to Timing Protection Mechanisms (AUTOSAR:타이밍 보호 메커니즘 적용 가능한 마감시간 준수 스케줄링 방법)

  • Kim, Joo-Man;Kim, Seon-Jong;Kim, Byoung-Chul;Kwon, Hyeog-Soong
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.1
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    • pp.103-109
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    • 2019
  • The automotive electronic system should provide a method that can be safely performed by loading a number of application programs having time constraints in several electronic control devices. In this paper, we propose a timing protection mechanism for AUTOSAR, which is a real - time operating system specification for automotive field, in order to observe the deadline of each task when scheduling real - time tasks. We propose a dynamic non-preemption algorithm to guarantee a flexible deadline for fixed priority or dynamic priority tasks, and a location where execution time can be monitored for errors, and suggest ways to implement the AUTOSAR time protection mechanism.

The Implementation of Real Time Communication Simulation using TMO in Distributed Network systems (분산네트워크시스템에서 TMO를 이용한 실시간 통신 시뮬레이션 구현)

  • Kim, Gwang-Jun;Seo, Jong-Joo;Kang, Ki-Woong;Yoon, Chan-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.5
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    • pp.897-905
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    • 2007
  • In this paper, we present a new framework and synchronization mechanism to effectively support developing real-time communication service by using a real-time object model named TMO (Time-Triggered Message-Triggered Object). Also, we describes the application environment as the DHS(distributed high-precision simulation) to guarantee real-time service message with TMO structure in distributed network systems. The TMO scheme is aimed for enabling a great reduction of the designer's effort in guaranteeing timely real-time communication service capabilities of among distributed multi-nodes systems. Our real-time framework provide the consistent construction and configuration of tine-triggered processing components across heterogeneous distributed object environment more easily. It has been formulated from the beginning with the objective of enabling design-time guaranteeing of timely action. In the real time simulation techniques based on TMO object modeling, we have observed several advantages to the TMO structuring scheme. TMO object modeling has a strong traceability between requirement specification and design.

Sub-Optimal Route Planning by Immuno-Agents

  • Takakazu, Ishimatsu;Chan, Tony
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.89.6-89
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    • 2001
  • In Vehicle Information and Communication System (VICS), which is an active field of Intelligent Transport System (ITS), information of traffic congestion is sent to each vehicle at real time. However, a centralized navigation system is not realistic to guide millions of vehicles in a megalopolis. Autonomous distributed systems should be more flexible and scalable, and also have a chance to focus on each vehicle´s demand. This paper proposes a sub-optimal route planning mechanism of vehicles in urban areas using the non-network type immune system. Simulation is carried out using a cellular automaton model. This system announces a sub-optimal route to drivers in real time using VICS.

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Layered Media Data Transmission Mechanism Of Considering Adaptive Dynamic QoS Control (동적 QoS 적응을 고려한 계층적 미디어 데이터의 전송 기법)

  • 나윤주;이승하;박준호;남지승;마평수
    • Proceedings of the IEEK Conference
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    • 2001.06c
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    • pp.97-100
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    • 2001
  • A common network such as internet does not provide a guaranteed network bandwidth to accommodate multimedia service in a reliable fashion. In this paper, we propose a new rate control mechanism for multimedia service on the internet which is adaptive to the dynamic QoS in real-time. Also we adapt an QoS monitoring module and real-time transmission control module to adapt dynamic network bandwidth. To do this, we used layer attribution of media data and also considered loss rate and buffer threshold in receiver side for measurement of dynamic QoS.

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A Shared Library as an Active Memory Object for Application Software Development of Large Scale Real-time Systems (대형 실시간 시스템의 응용 소프트웨어 개발을 위한 능동적 메로리 개체로서의 공유 라이브러리)

  • 정부금;차영준김형환임동선
    • Proceedings of the IEEK Conference
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    • 1998.10a
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    • pp.233-236
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    • 1998
  • In this paper, we present a novel approach named a shared library as an active memory object for application software development of large-scale real-time systems. Unlike the general passive shared memory, shared library proposed in this paper can be activated as an execution object. Moreover this is not tightly coupled with application programs unlike the normal libraries. To implement this mechanism, operating system makes the shared memory as an active object and shared library realizes the indirect call structure. This mechanism enhanced the utilization of main memory and communication performance. And this is successfully applied to the HANbit ACE ATM switching system and the TDX-10 switching system.

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자율주행 로봇을 위한 Laser Range Finder

  • 차영엽;권대갑
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1992.10a
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    • pp.266-270
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    • 1992
  • In this study an active vision system using a laser range finder is proposed for the navigation of a mobile robot in unknown environment. The laser range finder consists of a slitted laser beam generator, a scanning mechanism, CCD camera, and a signal processing unit. A laser beam from laser source is slitted by a set of cylindrical lenses and the slitted laser beam is emitted up and down and rotates around the robot by the scanning mechanism. The image of laser beam reflected on the surface of an object is engraved on the CCD array. A high speed image processing algorithm is proposed for the real-time navigation of the mobile robot. Through experiments it is proved that the accurate and real-time recognition of environment is able to be realized using the proposed laser range finder.

The Synchronization of WWW Browsers between Server and Client on Web-based Real-time Remote Lecture (웹 기반의 실시간 원격강의를 위한 서버와 클라이언트간의 웹브라우저 동기화)

  • Lee, Jeom-Suk;Lee, Bu-Gwon;Seo, Yeong-Geon
    • The KIPS Transactions:PartA
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    • v.8A no.1
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    • pp.70-74
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    • 2001
  • A general web-based remote lecture system uses video data and audio data to provide synchronize between teacher and students. This system requires high bandwidth, high speed networking, television, compression and computing technologies between server and client for remote lecture over Internet. As a result, this system can decrease an efficiency for lecturing over current Internet. So, this paper proposes a new mechanism calling as ‘Synchronization of WWW browsers between server and client’to cope with above problems and finally pursues low cost needed for real-time remote lecture over Internet. The mechanism means that every browser of teacher and students displays the same page and the action of teacher is transferred to the browser of student. And, this can be implemented by Windows hooking APIs, Memory Mapping, and DLL (Dynamic Link Library) programming technology. This paper points to the design and implementation of LAS (Lecture Assistant Server) and LAC (Lecture Assistant Client) to perform the synchronization between server and client.

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A Ticket-based Authentication Mechanism Suitable for Fast 802.11 Handoff which use CAPWAP Architecture (고속의 802.11 핸드오프를 지원하는 CAPWAP 아키텍처를 이용한 티켓 기반의 인증 메커니즘)

  • Park, Chang-Seop;Woo, Byung-Duk
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.19 no.6
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    • pp.93-103
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    • 2009
  • Recently, there is an increase in demand of real-time multimedia service in the WLAN environment, with a commercialization of IEEE 802.11n standard. However, the 802.1x authentication protocol is too slow to provide seamless real-time multimedia service, which defined in an IEEE 802.11i security standard. In this paper, a Ticket-based authentication mechanism in the CAPWAP(Control And Provisioning Wireless Access Point) architecture is introduced to support for the fast handoff.

Design and Implementation of the Higher-quality Terrestrial 3DTV Broadcasting Standard Specification Based on Synchronization with Non-Real-Time Contents (고화질 스테레오스코픽 영상 서비스를 위한 비실시간 콘텐츠 연동 지상파 3DTV 방송 표준규격 설계 및 검증)

  • Lee, Jangwon;Kim, Kyuheon;Yim, Hyun-Jeong;Cheong, Won-Sik
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37C no.12
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    • pp.1185-1194
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    • 2012
  • This paper proposes a new terrestrial 3DTV broadcasting standard specification based on synchronization with non-real-time contents in order to overcome quality limitations of the current 3DTV services that are arisen from the limited bandwidth of the legacy broadcasting channel. In the services using the proposed specification, one view sequence of a stereoscopic video content is delivered as a non-real-time content in idle time, and the other view sequence is transmitted in real time broadcasting signal, thereafter two sequences are synchronized in a receiver for display. Thus, it is possible to provide higher-quality stereoscopic video content services than the current 3DTV services. In order to realize these services, a new mechanism is required which enables synchronization between the data that are from different transmission media and time. Therefore, this paper suggests a solution by multiplexing the synchronization signals of non-real-time contents into broadcasting signals with real-time streams together. This solution can provide a accurate synchronization mechanism by minimum updates of legacy broadcasting systems while maintaining compatibility with legacy services.