• Title/Summary/Keyword: Real time operating system

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Analysis on Operation of Anti-Virus Systems with Real-Time Scan and Batch Scan (실시간스캔과 배치스캔을 갖춘 안티바이러스시스템의 운영 분석)

  • Yang, Won Seok;Kim, Tae-Sung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38B no.11
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    • pp.861-869
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    • 2013
  • We consider an information system where viruses arrive according to a Poisson process with rate ${\lambda}$. The information system has two types of anti-virus operation policies including 'real-time scan' and 'batch scan.' In the real-time scan policy, a virus is assumed to be scanned immediately after its arrival. Consequently, the real-time scan policy assumes infinite number of anti-viruses. We assume that the time for scanning and curing a virus follows a general distribution. In the batch scan policy, a system manager operates an anti-virus every deterministic time interval and scan and cure all the viruses remaining in the system simultaneously. In this paper we suggest a probability model for the operation of anti-virus software. We derive a condition under which the operating policy is achieved. Some numerical examples with various cost structure are given to illustrate the results.

A hybrid prioritized worker model for efficiency of shared resources in the real-time system (실시간 시스템에서 공유자원의 효율적 사용을 위한 혼합형 우선순위 작업자 모델)

  • Park, Hong-Jin;Chun, Kyung-Ah;Kim, Chang-Min
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.12
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    • pp.3652-3661
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    • 1999
  • To support multimedia applications such as a multimedia communication systems and multimedia broadcasting, an operating system need to predict their timing-constraints. So, In this real-time systems, we must solve the priority inversion problem that may make the behavior of unpredictable systems and need a real-time server model that provides a better preemptability and minimizes a system overhead. In current real-time systems, the single thread server model, the worker model and the dynamic server model are being used for synchronization but they cannot propose an effective structure for managing shared resources. In this paper, the priority inheritance protocol is used to solve the priority inversion problem and the hybrid prioritized worker model is proposed, which can provide a more effective structure and a faster response time minimizing a system overhead. The hybrid prioritized worker model is to combine the static and the dynamic prioritized worker model, and have a better performance than other models in response time which is an important factor in a real-time system.

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Linux-based ARINC 653 Health Monitor (리눅스 기반 ARINC 653 헬스 모니터)

  • Yoon, Young-Il;Joe, Hyunwoo;Kim, Hyungshin
    • IEMEK Journal of Embedded Systems and Applications
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    • v.9 no.3
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    • pp.183-191
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    • 2014
  • The software running on avionic system is required to be highly reliable and productive. The air transport industry has developed ARINC Specification 653(ARINC653) as a standardized software requirement of avionics computers. The document specifies the interface boundary between avionics application software and the core executive software. Dependability in ARINC 653 is provided by spatial and temporal partitioning whilst fault-tolerance is provided by health monitoring mechanism. Legacy real-time operating systems are used to support ARINC653 health monitor on integrated modular avionics(IMA). However, legacy real-time operating systems are costly and difficult to modify the kernel. In this paper, we suggest a Linux-based ARINC653 health monitor. Functionalities to support ARINC653 health monitor are implemented as a Linux kernel module and its performance is evaluated.

A design of supervisory control system for a multi-robot system (다중로봇을 휘한 관리제어 시스템의 설계)

  • 서일홍;여희주;김재현;류종석;오상록
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.45 no.1
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    • pp.100-112
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    • 1996
  • This paper presents a design experience of a control language for coordination of a multi-robot system. To effectively program job commands, a Petrinet-type Graphical Robot Language(PGRL) is proposed, where some functions, such as concurrency and synchronization, for coordination among tasks can be easily programmed.In our system, the proposed task commands of PGRL are implemented by employing formal model languages, which are composed of three modules, sensory, data handling, and action module. It is expected that by using our proposed PGRL and formal languages, one can easily describe a job or task, and hence can effectively operate a complex real-time and concurrent system. The control system is being implemented by using VME-based 32-bit microprocessor boards for supervisory, each module controller(arm, hand, leg, sensor data processing module) and a real time multi-tasking operating system(VxWorks). (author). 17 refs., 16 figs., 2 tabs.

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Construction and Application of a Web-EOC Based Real-Time Monitoring Management System in Steep Slopes (Web-EOC 기반 경사지 실시간 계측관리시스템 구축 및 적용)

  • LEE, Jin-Duk;CHANG, Ki-Tae
    • Journal of the Korean Association of Geographic Information Studies
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    • v.21 no.2
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    • pp.107-119
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    • 2018
  • The slope monitoring systems which have been operating at home and abroad were investigated and then the real-time monitoring management system for evacuating inhabitants based on Web-EOC(Emergency Operating Center) was constructed. We tried to analyze realistically and precisely the situation by changing from the existing field-centered management to sensor-centered management that measures coordinates and provides in real-time data of measuring/monitoring sensors installed at a field site and developing related viewer programs. In addition, the 3D based monitoring management system, which has alarm functions in case of emergency and provides information about the evacuation place, was constructed on the base that is able to expand to nationwide fields by using Vworld 3D map. Ten steep slope monitoring sites were registered on Web-EOC slope monitoring management system constructed in the research and then application instances were suggested.

Development of Android App for Suppor ting Smooth Multimedia Streaming Service Using Frame Buffer (프레임 버퍼를 이용한 매끄러운 멀티미디어 스트리밍 서비스를 지원하는 안드로이드 앱 개발)

  • Seo, Sang-min;Kwon, Jonnho;Choi, Yoon-Ho
    • Journal of Internet Computing and Services
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    • v.17 no.1
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    • pp.55-64
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    • 2016
  • Existing Android applications for streaming video in real time are dependent on the codec, which composes the encoding function, and the version of Android operating system. Also, for streaming video in real time, most applications should be connected with a separate desktop PC. To overcome these disadvantages, we propose a new application, which records and streams video in real time. Specifically, the proposed application uses the flash video file format, which is the common media file format supported by various versions of Android operating system. Through experiments, we show that it is possible for the proposed application to record the video screens more than 20 frames per second and to stream it in real time while using the existing video encoding methods.

Implementation of Dual Cycle in Container Yard based on Ad-hoc Networks (Ad-hoc 네트워크 기반의 컨테이너장치장의 Dual Cycle 구현)

  • Park, Doo-Jin
    • Journal of Fisheries and Marine Sciences Education
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    • v.25 no.4
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    • pp.998-1007
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    • 2013
  • At container terminals, a major measurement of productivity can be work efficiency. For improving the productivity of container crane, the more efficient container yard operation method is necessary in container terminals. Recently, container terminal operators make an experiment on the dual cycle operation, which ship loading/unloading were carried out simultaneously, for increasing the productivity of container crane. In this paper, propose a system operating efficient dual cycle methods as utilize Ad-hoc technology in distributed port operation system. The dual cycle methods that proposed recognizes position information of Y/T during an action in Ad-hoc networks in case of container transfer works by real time as load an Ad-hoc module to Y/T taking charge of a container transfer with quay and yard. Utilize Ad-hoc networks technology in an operating system of container yard, and efficiently distributed processing done Y/T to container crane compare with operation systems of the existing dedicated method, and an improvement can do an operating system of an yard.

An Implementation of Remote Monitoring System for Control Relay (제어용 계전기의 원격감시시스템 구현)

  • Chang, Yong-Hoon;Nam, Jae-hyun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.11
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    • pp.2100-2106
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    • 2016
  • The automation system uses PLC to monitor the manufacturing process status of the production product and processes the sensor information transmitted from the sensor. In this paper, we propose a remote surveillance system to monitor the status of control relay used in automation system. The proposed system consists of a control relay module, a one-chip processor module, a computer monitoring system, and a database system that inputs and manages the details of the control relay. The computer monitoring system is configured to monitor the operating condition and life time of the control relay. The database is configured so that the input date of the control relay can be input and corrected, and the operating state information of the control relay can be automatically printed. In the remote monitoring system, the failure status of the control relay is recognized in real time, and the time required for normal operation can be minimized by quickly replacing faulty parts.

A Study on the Analysis of Performance for a Real-time Distributed Control System with Reliability (신뢰성 있는 실시간 분산제어 시스템의 성능분석에 관한 연구)

  • Kim, Nae-Jin;Park, In-Kap
    • Journal of IKEEE
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    • v.2 no.2 s.3
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    • pp.270-277
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    • 1998
  • As the network technologies advance, the control systems progress from a centralized architecture to a distributed one. However, these control systems were designed mostly based on the general-purpose operating systems(OS) and have many problems for assurance of a real-time property required for plant processing fields. Therefore, the control systems far a plant process upon real-time OS hare been increased gradually. In this paper, the real-time OS emphasizes on the realization of real-time processing capability, reliability of real-time response, and multi-processing functionality which are prerequisites for a distributed control system. And on the basis of this OS, the number of executable loop and logic, the functions of main plant processing, was analyzed and its validity was also evaluated. The system in this paper was designed not to effect on processing data while online, and the time spent on switching was measured.

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Development of Operating S/W and DBMS for Deep-sea Manganese Nodule Miner (심해저 망간단괴 집광기의 운영 소프트웨어 및 데이터베이스 관리시스템 개발)

  • Park, Soung-Jae;Yeu, Tae-Kyeong;Yoon, Suk-Min;Hong, Sup;Kim, Hyung-Woo;Choi, Jong-Su;Kim, Sang-Bong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.13 no.3
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    • pp.229-236
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    • 2008
  • The deep-sea miner is the tracked vehicle system which drives on the deep-seabed and gathers a manganese nodules. The miner is operated by remote control in real-time by the station of surface vessel. So operating S/W is a important part of miner remote operating. At present, the test miner has been designed and manufactured for near-shore sea-test. The test miner consists of mechanical parts, and electric-electronic parts. Because those parts should be controled and monitored remotely, operating S/W for control and monitoring is necessary by all means. In this paper, real-time operating S/W for a control and monitoring of the test miner was designed and developed using PXI, embedded controller and LabVIEW. This real-time operating S/W was developed for an efficient test of test miner in a near seabed area. Moreover, database management system(DBMS) was developed too for the data management of test miner monitoring using MS SQL and LabVIEW.