• 제목/요약/키워드: watchdog

검색결과 48건 처리시간 0.034초

루프 검출 및 예측 방법을 적용한 비용 효율적인 실시간 분기 흐름 검사 기법 (A Cost-effective Control Flow Checking using Loop Detection and Prediction)

  • 김근배;안진호;강성호
    • 대한전자공학회논문지SD
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    • 제42권12호
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    • pp.91-102
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    • 2005
  • 최근의 저 전력 컴퓨터 시스템은 내장 프로세서의 성능 향상과 공정 기술의 발전을 통한 디바이스 크기 감소로 인해 전압 변동, 커플링 효과 등으로 인한 SEU(single event upset)로 모델링 되는 천이고장으로 인한 예기치 못한 동작 중 에러 발생가능성이 매우 높아지고 있다. 제안하는 방식은 프로세서가 처리하는 프로그램 분기 흐름상에서 에러를 검출하는 효과적인 watchdog 프로세서 구조로서, 기존 방식이 가지는 오버헤드를 줄이면서 프로그램 내부에서 빈번히 발생되는 루프를 매번 검사할 때, 동일한 동작을 watchdog 프로세서가 반복함으로써 생기는 비효율적인 메모리 접근, 버스 점유 경쟁등과 같은 추가적인 시스템 수준의 오버헤드를 줄이는 새로운 방법을 제안하였다. 본 논문은 기존의 실시간 분기 및 제어 흐름 연구에서는 다루지 않았던 루프 검출 및 예측 기능을 추가함으로써 실제 시스템 적용에 보다 적합한 비용 효율적인 구조를 제안하고 있다.

한국의 민주화와 미디어 : 정부와 시장 주류 미디어의 관계 (The relationship between the major market-based media and the government in Korea)

  • 조항제
    • 한국언론정보학보
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    • 제16권
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    • pp.168-206
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    • 2001
  • This study attempts to examine the relationships between the major market-based media and the government after closing military regime era, 1961-1987. After the military regime was collapsed, while the mass media in Korea obtained independence and autonomy from government, they have been confronted with the terrible competition not so much comparatively as before. The watchdog role in the traditional liberalism, which is regarded as normative relationship between the media and the government would be transformed in accordance with the market condition and the maturity of democracy. Thus, the watchdog metaphor has been variously deviated in rower-centered society; lap dog, guard dog, attack dog. liberalists argue that the primary democratic role of the media is to art as a public watchdog overseeing the state. Social democrats, however, criticize them as simplistic conception which could be only applied to the government. They argue that the media should be seen as a source of redress against the abuse of all forms of power over others; the home, the economy, and the civil society. The lap dog view is that the media is overwhelmingly dependent on the established power structure contrary to the watchdog. While the guard dog perspective is a means to preserve the power structure alarming with playing 'conflict role', the attack do8 aims to the private interest of the media in intruding into the politics. The attack dog perspective by T. Patterson could be composed of the interpretive style of report, the game schema report over the policy schema in the election, and the negativism against politics and government. The market-dominant press has been likely to transform from lap-guard dog into attack-guard dog. In Roh Tae Woo government(1988-1992), while the press was a lessened lap-guard dog before three parties merger in 1990, after merger the press had been transformed as the reinforced lap-guard dog because this merger entailed joint, party-to-party negotiations, and the formation of the new party preceded by dissolution of the ruling blot. In the early stage of Kim Young Sam government(1993-1997), the press has kept in pace with the reform movement drive-forced by the government. However, the press withdrew the support of Kim's reform in reaching the level of threat to ruling bloc. The press coalesced only circumstantially with government and was interested in preserving some margin of independence. The failure of Kim's reform proved the political muscle of the press in post-autho-ritarianism. In the middle stage of Kim Dae Jung government (1998-) that resulted in the shift of power structure as once-opposition party leader, the stress has been a manifested attack-guard dog owing to the anti-cold war policy, the realignment policy of power, and the minority-base of Kim's government. The press has endeavored to hold political communication within limits relatively less threatening to the established order.

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화공플랜트 견적 소프트웨어 개발에 관한 연구 (Development of the Estimation Software for a Petrochemical Plant)

  • 민봉기;이재헌
    • 플랜트 저널
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    • 제8권1호
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    • pp.50-59
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    • 2012
  • The current dual-watchdog estimation system has individually calculated the construction, the engineering and the procurement cost. The dual-watchdog estimation system is inefficient and prolonged estimation period because of the lack of the interoperability and the difference of material unit cost and construction unit cost. In order to resolve this problem, new estimation software was developed. The estimation software is developed by making up for the weak points in existing estimation method. The cost data with the same standard is the key point. And this software enhanced accuracy and speed of the data search in stylized estimation standard. A summary of the construction, the engineering and the procurement cost was generated in this estimation software. The unit rate about the labor cost, equipment and expense through a sheet was handled. The developed estimation software has five categories on engineering cost, procurement cost, construction cost and subcontractor management sheet. In this study, the estimation software to supplement the faults of the existing estimation method was developed. And estimation software on petrochemical projects increases an efficiency of the estimation work.

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이동통신 단말기용 16 비트 마이크로콘트롤러의 주변장치 개발 (Development of Peripheral Units of the 16 bit Micro-Controller for Mobile Telecommunication Terminal)

  • 박성모;이남길;김형길;김세균
    • 전자공학회논문지A
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    • 제32A권9호
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    • pp.142-151
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    • 1995
  • The trend of compact size, light weight, low power consumption in the portable telecommunication equipments demands large scale integration and low voltage operation of chips and the minimization of the number of the components in the telecommunication terminal. According to the trend, existing chip components are modulized and are integrated as a part into a bigger chip. This paper is about the development of the peripheral units of micro-controller for mobile telecommunication terminal. Peripherals consist of DMA controller, Interrupt controller, timer, watchdog timer, clock generator, and power management unit. They are designed to be integrated with EU(Execution Unit) and BIU(Bus Interface Unit) into a 16 bit micro-controller which will be used as a core of an ASIC for next generation digital mobile telecommunication terminal. At first, whole block of the micro-controller was described by VHDL behavioral model and simulated to verify its overall operation. Then, watchdog timer, clock generator and power management unit were directly synthesized by using VHDL synthesis tool. Rest of the pheriperal units were designed and simulated by using Compass Design Tool.

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가상공간의 가공 공정과 상태 구현에 관한 연구 (A Study on Realization of Machining Process and Condition in Virtual Space)

  • 이수훈;김봉석;홍민성;김종민;;박상호;송준엽;이창우;하태호
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2005년도 춘계학술대회 논문집
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    • pp.462-467
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    • 2005
  • This paper presents virtual machining system in order to realize turning process in virtual space. A reliable virtual turning process simulation was developed based on the surface shaping system which is capable of considering geometric model, thermal error model, and vibration model. Accuracy of surface shape resulting from proposed machining simulator was verified experimentally. This paper also developed the watchdog agent that continuously assessed, diagnosed, and predicted performance of products and machines in machining. The Watchdog agent extracted feature signal using time-frequency analysis among various signals from multi-sensor and evaluated machining condition using performance confidence value.

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8bit RISC 프로세서를 이용한 LED Array의 조도제어 IP 구현 (Implementation of The LED illuminance control IP based on 8bit RISC Processor)

  • 오은택;문철홍
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2008년도 하계종합학술대회
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    • pp.603-604
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    • 2008
  • This paper implemented The LED illuminance control IP based on 8bit RISC Processor. 8bit RISC Processor designed hardware interrupts, an interface for serial communications, a timer system with compare-capture-reload resources and a watchdog timer. LED Array consists of Red, Green, Blue, White and Warm White. The illuminance control IP is used to LED Board control with 8bit data.

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Design of a Fault-tolerant Embedded Controllerfor Rail-way Signaling Systems

  • Cho, Yong-Gee;Lim, Jae-Sik
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2002년도 ICCAS
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    • pp.68.4-68
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    • 2002
  • $\textbullet$ This report presents an implementation a set of reusable software components which use of fault-tolerance embedded controller for railway signalling systems. These components can be used in real-time applications without application reprogramming. $\textbullet$ This library runs under VxWorks operating system and is oriented on real-time embedded systems. The library includes fault detection, fault containment, checkpointing and recovery components. $\textbullet$ The library enables to support high-speed response to fault occurrence in application software. Garbage collector together with VxWorks Watchdog provides both dead tasks detection and useless resources removing to avoid an overflow. Control flow...

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Automatic Recovery and Reset Algorithms for System Controller Errors

  • Lee, Yon-Sik
    • 한국컴퓨터정보학회논문지
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    • 제25권3호
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    • pp.89-96
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    • 2020
  • 본 논문은 시스템 내부에서 소프트웨어 오류가 발생하였을 경우 컨트롤러 내의 Watchdog Timer를 이용하여 시스템의 상태를 오류 발생시점 이전 상태로 복구하는 시스템을 설계 구현하고, 하드웨어 오류 발생 시 별도의 리셋 회로를 통해 시스템을 재실행할 수 있는 기술을 제안한다. 제안 시스템은 외부 지원 없이 시스템 자체적으로 반영구적으로 작동 할 수 있도록 함으로써, 시스템의 안정적인 작동, 유지비용 절감 및 신뢰성을 제공하며, 고 신뢰성 응용분야에서 요구되는 자가 동작, 진단 및 복구 기능을 통한 시스템의 항상성 유지를 위한 적용이 가능하다.

다중 Gigabit Server NICs에서 동적 검출 주기를 적용한 결함 허용 메커니즘 (A Fault Tolerance Mechanism with Dynamic Detection Period in Multiple Gigabit Server NICs)

  • 이진영;이시진
    • 인터넷정보학회논문지
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    • 제3권5호
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    • pp.31-39
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    • 2002
  • 인터넷의 초고속 성장과 멀티미디어 데이터의 급격한 증가로 고속의 전송 매체와 인터페이스 시스템이 요구되고 있다. 이러한 고속의 네트워크 대역폭을 지원하기 위한 대안으로 다중(Multiple) NIC가 개발되고 연구되어 왔다. 다중 NIC를 사용함으로써 기존 네트워크 환경의 큰 변화 없이 고속의 LAN 환경을 구축할 수 있으므로 고성능. 저비용의 효과를 얻을 수 있다. 그러나 대용량 다중 NIC에 SPOF(Singe Point Of Failure) 결함으로 시스템 중단이 생기면, 대용량의 멀티미디어 데이터를 서비스하는 시스템인 만큼 커다란 손실을 가져오게 된다. 따라서 본 논문에서는 결함으로 오는 손실을 방지하기 위해 결함 허용 기법을 사용하여 '결함 허용 다중 NIC'에 대해서 연구한다. 기존의 TMR, Primary-Standby 기법. Watchdog Timer 기법에서 발생되는 자원에 대한 가용성과 내구성의 비효율적인 부분을 고려하여, 동적으로 검출 주기를 변환하여 다운타임을 최소화 할 수 있는 효율적인 결함 허용 메커니즘을 설계하여 제안한다. 결과적으로 본 논문에서 제안한 결함 허용 기법은 결함이 발생하여 생기는 오버헤드 시간을 줄이고자, Fault Detection에서 소요되는 Timeout 시간을 감소시켜 시스템 전반적으로 다운타임을 최소화시킬 수 있다.

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