• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.711-714
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• 1998

본 논문에서는 wide data-width DRAM을 위한 flexible column redundancy scheme을 제안하였다. 구현된 redundancy scheme은 DB line shift method를 사용하여 wide data-width를 갖는 고집적 DRAM에 적용할 때 기존 redundancy scheme보다 더 작은 redundancy cell 면적과 fuse개수를 가지면서 더 큰 flexibility를 가지게 되었다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1229-1232
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• 1996

This paper proposes the passive redundancy algorithm of multi-controller structure applicable to the steam generator level control system in the low power operating range. In the passive redundancy scheme of multi-controller structure, two suitable controllers exist if the plant is strongly stabilizable. One of the two controllers can be selected arbitrarily only if it is stable. In particular, this paper shows that the passive redundancy scheme can be efficiently used with PID and GPC control algorithms through simulation studies on the control of the steam generator.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.468-471
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• 2012

본 논문은 우주발사체에 사용되는 추진기관의 성능평가를 수행하기 위한 지상연소시험설비의 이중화 또는 삼중화 제어시스템의 구축 방안을 다루고 있다. 이중화된 제어시스템의 경우 수동제어 콘솔을 설치하여 삼중화 제어시스템을 모사할 수 있었고, 운용자들의 무분별한 조작을 통제하기 위한 제어실 내 제어 콘솔의 배치 안을 제시하였다.

• Journal of Electrical Engineering and Technology
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• 제2권3호
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• pp.379-385
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• 2007

Recently, vital devices of the railway signaling systems have been computerized in order to ensure safe train operation. Due to this computerization, we have gradually come to need networking interfaces between these devices. Thus it is important that there be reliable communication links in the signaling systems. Network technologies are applied in the real-time industrial control system, and there are numerous studies to be carried out on the computer network technology for vital control systems such as railway signaling systems. For deploying the studies, we consider costs, reliability, safety assurance technique, compatibility, and etc. In this paper, we propose the Ethernet for railway signaling systems and also precisely describe the computer network characteristics of vital railway signaling systems. Then we demonstrate the experimental results of the proposed network algorithm, which is based on switched Ethernet technology with redundancy scheme.

• 한국정보통신학회논문지
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• 제20권9호
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• pp.1717-1722
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• 2016

가용도는 사용자에게 고가용 서비스를 제공하는 네트워크 시스템의 주요 성능지표로서 임의의 시간에 사용자에게 서비스를 제공할 수 있는 확률이다. 네트워크 서비스의 가용도를 향상시키는 대표적인 방법으로 다중화 방식과 재활기법이 있다. 본 논문에서는 2N redundancy와 시간 기반의 재활기법이 가용도에 미치는 영향을 분석한다. 2N redundancy는 active 시스템과 standby 시스템으로 구성하는 다중화 방식이다. 재활주기에 의존하는 시간기반의 재활기법이다. 본 논문은 시간기반의 재활기법을 적용한 2N redundnacy모델을 stochastic reward net으로 설계한다. 설계한 모델은 stochastic Petri net package를 이용하여 분석한다. 수치해석을 통해 재활기법을 적용한 시스템의 가용도가 적절한 주기에서 재활기법을 적용하지 않은 시스템의 가용도보다 높다는 것을 알 수 있다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제5권5호
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• pp.1013-1027
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• 2011

In this paper we propose ATCS, a practical TCP protocol coding scheme based on network coding for satellite IP networks. The proposal is specially designed to enhance TCP performance over satellite networks. In our scheme, the source introduces a degree of redundancy and transmits a random linear combination of TCP packets. Since the redundant packets are utilized to mask packet loss over satellite links, the degree of redundancy is determined by the link error rates. Through a simple and effective method, ATCS estimates link error rates in real time and then dynamically adjusts the redundant factor. Consequently, ATCS is adaptable to a wide range of link error rates by coding TCP segments with a flexible redundancy factor. Furthermore, the scheme is compatible with traditional TCP variants. Simulation results indicate that the proposal improves TCP performance considerably.

• 한국통신학회논문지
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• 제23권8호
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• pp.1977-1983
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• 1998

본 논문에서는 인코더 벡터(encoder vector)에 입각하여 양, 음 체크썸 벡터(positive, negative checksum vector)를 정의하고, 이를 벡터 컨버루션(vector convolution)에 적용하여 알고리즘 기반 결함허용 벡터 컨버루션 방식을 제안하였다. 또한 제안된 방식을 배열구조에서 구현하고 복잡도 해석을 통하여 추가 리던던시(redundancy)의 규모를 검토하였다.

• 한국정보컨버전스학회:학술대회논문집
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• 한국정보컨버전스학회 2008년도 International conference on information convergence
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• pp.157-160
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• 2008

The pursuit of efficiency is taken for granted in today's public administration, and the limit of this study exists in the point that we should carefully deal with combining the redundancy scheme to the public administration. Accordingly, although this study should suggest the specific plans and backgrounds of the needs for the redundancy, it will only find out the applicability of the redundancy to the public administration for its purpose. Redundancy means the excess or superfluity in something, which means the surplusage status ranging from the wasteful and excessive supplies, insignificant additions, to the surplusage in a legal pleading. The emphasis of this study is placed on the changes in the rigidity in believing that the removal of the redundancy from the public administration is the best option in any case of the efficiency. In addition, the necessity of the overlapped organization should not be neglected by the concept of the efficiency. Indeed, it is necessary to correct the overlapped function of superfluity and ambiguity public administration, in order to remove the neglect conflicts between the organizations, to guarantee the inconsistency in the public administration and to ensure the efficiency in the public administration volunteering.

• 제어로봇시스템학회논문지
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• 제20권6호
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• pp.625-630
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• 2014

Asynchronous digital circuits working in military and space environments are often subject to the adverse effects of radiation faults. In this paper, we propose a new hardening technique against radiation faults. The considered digital system has the structure of DMR (Double Modular Redundancy), in which two sub-systems conduct the same work simultaneously. Based on the output feedback, the proposed scheme diagnoses occurrences of radiation faults and realizes immediate recovery to the normal behavior by overriding parts of memory bits of the faulty sub-system. As a case study, the proposed control scheme is applied to an asynchronous dual ring counter implemented in VHDL code.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2004년도 한국우주과학회보 제13권2호
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• pp.266-269
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• 2004

A satellite ground control system (SGCS) which monitors and controls a geostationary satellite 24 hours a day has to achieve the system architecture assuring high-level availability and redundancy scheme. The SGCS for Communication, Ocean, and Meteorological Satellite (COMS) is currently being developed in Korea, which will be implemented to satisfy high availability (HA), expansibility, and compatibility in design. In order to implement the system architecture to meet these characteristics, the SGCS for COMS introduces the concept of the real-time distributed system structure based on redundancy scheme for high availability, data replication and sharing, and CORBA middleware.