• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.2
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• pp.29-38
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• 2010

Network Video Recorder becomes popular as a next generation surveillance system connecting all cameras and video server in network environment because it can provide ease of installation and efficient management and maintenance. But in case of data damage, the storage device in traditional NVR has no recovery scheme and it is disabled in processing real-time requests. In this paper, we propose an Reliable Storage using Parity and Mirroring scheme for improving reliability on storage device and maintaining system on realtime. RSPM uses a Liberation coding to recover damaged multimedia data and dynamic mirroring to repair corrupted system data and to maintain real-time operation. RSPM using the Liberation code is 11.29% lesser than traditional file system and 5.21% less than RSPM using parity code in terms of loss rate of damaged multimedia data.

• Journal of KIISE
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• v.42 no.1
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• pp.7-14
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• 2015

Storage Class Memory(SCM) has been considered as a next-generation storage device because it has positive advantages to be used both as a memory and storage. However, there are significant problems of data consistency in recently proposed file systems for SCM such as insufficient data consistency or excessive data consistency-control overhead. This paper proposes a novel data consistency-control scheme, which changes the write mode for log data depending on the modified data ratio in a block, using a rollback-recovery scheme instead of the Write Ahead Logging (WAL) scheme. The proposed scheme reduces the log data size and the synchronization cost for data consistency. In order to evaluate the proposed scheme, we implemented our scheme on a Linux 3.10.2-based system and measured its performance. The experimental results show that our scheme enhances the write throughput by 9 times on average when compared to the legacy data consistency control scheme.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.6
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• pp.1190-1194
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• 2007

In sensor network, the importance of transporting data with reliability is growing gradually to support communications. Data flow from sink to nodes needs reliability for the control or management, that is very sensitive and intolerable, however relatively, data flow from nodes to sink is tolerable. In this paper, with emphasis of the data flow from sink to nodes, we proposed the mechanism that establishes confidence interval for transport. Establishing confidence interval herby-hop, not end to end, if errors happen or there's missing data, this mechanism recovers them with selective acknowledgement using fixed window. In addition, this mechanism supports franc congestion control depending on the buffer condition. Through the simulation, we showed that this mechanism has an excellent performance for error recovery in sensor network.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.31 no.6
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• pp.1157-1169
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• 2021

The disaster recovery refers to policies and procedures to ensure continuity of services and minimize loss of resources and finances in case of emergency situations such as natural disasters. In particular, the disaster recovery method by the cloud service provider has advantages such as management flexibility, high availability, and cost effectiveness. However, this method has a dependency on a service provider and has a structural limitation in which a user cannot be involved in personal data. In this paper, we propose a protocol using proxy re-encryption for data confidentiality by removing dependency on service providers by backing up user data using blockchain and distributed storage. The proposed method is implemented in Ethereum and IPFS environments, and presents the performance and cost required for backup and recovery operations.

• Journal of the Korea Society of Computer and Information
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• v.29 no.6
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• pp.175-182
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• 2024

In wireless sensor networks, batteries limit lifespan, and heavy data transmission around the sink causes the hotspot problem. To address this, data collection amounts are allocated to child nodes to limit transmission. However, this approach has issues with nodes far from the sink having excessive energy and failing to transmit the allocated amount due to data transmission errors. This paper proposes a method to prevent sensor data loss through error recovery via retransmission. The method ensures that each node's retransmission volume stays within its allocated data amount and energy limits, using excess energy for error recovery. Simulations show that this technique effectively recovers data transmission errors, collects data, minimizes energy depletion around the sink, and increases data collection rates.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.9
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• pp.205-214
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• 2012

The main thing that IT operation managers consider is protecting assets of corporation from system failure and disaster. Therefore, this research proposed a backup system for a disaster recovery. Previous backup method is that if database update occurs, this record is saved in redo log, and if the size of record file is over than expected, this file is saved in archive log in order. Thus, it is possible to occur errors of data loss from the process of data backup which change in real time while changes of database occur. Suggested backup system is back redo log up to database of transaction log in real time, and back a record that can be omitted from previous backup method up to archive log. When recover the data, it is possible to recover redo log in real time online, and it minimizes data loss. Also, throughout multi thread processing method data recovery is performed and it is designed that system performance is improved. To verify stability of backup system CPN(Coloured Petri Net) is introduced, and each step of backup system is displayed in diagram form, and th e stability is verified based on the definition and theorem of CPN.

• Information and Communications Magazine
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• v.31 no.3
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• pp.3-11
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• 2014

본고에서는 Tele-Experience 실감 스마트워크 서비스를 제공하기 위한 기반 기술인 텔레프레즌스 기술동향에 대해 살펴본다. 최근의 텔레프레즌스 시스템은 회의 참여자들의 몰입감을 향상시키기 위해 다양한 신기술들을 채택하고 있는데, 본고에서는 실감 스마트워크 서비스를 위해 특별히 차별화할 수 있는 3가지 핵심 기술 - 시선 맞춤, 실감 오디오 기술, 그리고 끊김없는 미디어 재생을 위한 패킷손실 복구기술을 중심으로 그 동향을 분석한다.

• 방재와보험
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• s.38
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• pp.11-19
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• 1988

화재로 인한 인명 및 재산상의 손실을 예방하고 신속한 재해복구와 인명피해에 대한 적정한 보상을 하게 함으로써 국민생활의 안정에 기여함을 목적으로 1973년 5월 15일 민간방재전문기관으로 출범한 한국화재보험협회가 올해로 창립 15주년을 맞이했다. 화보협회는 그간 국민 생활안정을 통한 복지사회 건설이라는 막중한 사명감을 한시도 잊지 않는 채 특수건물을 비롯 기간산업에 대한 안건점검과 화재보험을 통하여 국가경제발전과 산업안전에 많은 기여를 해온 것으로 평가되고 있다. 창립 15주년을 맞아 이제 지난 15년간의 협회 발자취와 당면과제, 그리고 앞으로의 역할에 대하여 각계 전문가의 의견을 들어본다.

• Magazine of the Korean Society of Hazard Mitigation
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• v.3 no.3 s.10
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• pp.82-89
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• 2003

대만 국가과학위원회에서는 1998년에 지진재해 구조물 피해 사회경제적 손실을 위한 연구를 위해 HAZ-Taiwan 연구 project를 착수하였다. 관련 software인 TELES(Taiwan Earthquake Loss Estimation System)는 3가지 목표를 위해 다양한 입력 및 분석 module로 구성되어 있다. 1. 피해 지진후 재해 평가 2. 재해복구계획 및 가상 시나리오 제공 3. 재해보험을 포함한 재해대응방안 제시 본 논문은 초기재해평가에 이용될 분석 modules개발 및 적용에 초점을 맞추고 있으며, 분석 module은 지반운동강도 액상화 건물피해 및 사상자 평가분석을 포함하고 있다.

• THE HEALTH and ORGANIC FARMING
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• no.182
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• pp.1-24
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• 2002

사상 유례없는 태풍 '루사' 피해복구에 총력을!!/지구의 미래는 유기농업뿐이다!/헤어리벳치 실증재배기술 요약/내년 농업예산 삭감.축소편성 '파장'/아주 편리한 신개념 고추건조방법이란?/전국 친환경농업 품평.전시회/GMO (유전자변형식품) 이란무엇인가?/유기농업에의한 양계/9월중 농사정보/당신도 무병장수를 꿈꾸는가?/후사리움균(Fusarium)병의 방제법/영국의 유기농업 농가의 소득손실?/미생물의 질병방제 기작/영천시 유기농업 한마음대회 성료