• Title/Summary/Keyword: Data replication

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Optical PCB and Packaging Technology (광 PCB 및 패키징 기술)

  • Ryu, Jin-Hwa;Kim, Dong-Min;Kim, Eung-Soo;Jeong, Myung-Yung
    • Journal of the Microelectronics and Packaging Society
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    • v.18 no.1
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    • pp.7-13
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    • 2011
  • According to increasing of data transfer rate, printed circuit board (PCB) is required improvement of transmission speed. Optical PCB and its packaging technology can be one of the solutions that overcome the limitations of conventional electrical PCB. The data transmission capacity will be increased 10 Tbps at 2015. To this end, studies on various OPCB technologies are being conducted. For cost-effective and high- performance OPCB, studies of optical coupling by polymer replication process are conducted. In this work, optical waveguide and optical fiber array block were sequentially fabricated by polymer pattern replication method. Using this method we successfully demonstrate low loss optical fiber coupling between optical waveguide and optical fiber arrays. And researches on flip chip bonding process and using electro-optic connectors for packaging are conducted.

A Dynamic Data Replication Algorithm Using Hidden Markov Model for HDFS (HMM을 이용한 HDFS 동적 데이터 복제 알고리즘)

  • Park, Na-Young;Youn, Hee-Yong
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2014.07a
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    • pp.327-328
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    • 2014
  • 클라우드 컴퓨팅 환경에서는 시스템의 성능 및 비용적인 측면에서 정보 공유의 용이성, 장소의 제약성 최소화, 저장 공간의 효율적 사용을 위해 분산 파일시스템을 이용하고 있다. 하지만 현재 HDFS의 복제 정책은 모든 데이터에 3개의 복제복을 유지하도록 하고 있다. 하지만 이러한 정책은 데이터의 중요도, 이용빈도수를 반영하지 못한 정책으로 상이한 서비스 품질 및 신뢰성 수준을 반영하지 못한다. 본 논문에서는 Hidden Markov Model을 이용하여 데이터의 이용 빈도수에 따라 복사본의 개수를 조절하는 알고리즘을 제안한다.

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Shredding XML Documents into Relations using Structural Redundancy (구조적 중복을 사용한 XML 문서의 릴레이션으로의 분할저장)

  • Kim Jaehoon;Park Seog
    • Journal of KIISE:Databases
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    • v.32 no.2
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    • pp.177-192
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    • 2005
  • In this paper, we introduce a structural redundancy method. It reduces the query processing cost incurred when reconfiguring an XML document from divided XML data in shredding XML documents into relations. The fundamental idea is that query performance can be enhanced by analyzing query patterns and replicating data essential for the query performance. For the practical and effective structural redundancy, we analyzed three types of ID, VALUE, and SUBTREE replication. In addition, if given XML data and queries are very large and complex, it can be very difficult to search optimal redundancy set. Therefore, a heuristic search method is introduced in this paper. Finally, XML query processing cost arising by employing the structural redundancy, and the efficiency of proposed search method arc analyzed experimentally It is manifest that XML read query is performed more quick]y but XML update query is performed more slowly due to the additional update consistency cost for replicas. However, experimental results showed that in-place ID replication is useful even in having excessive update cost. It was also observed that multiple-place SUBTREE replication can enhance read query performance remarkably if only update cost is not excessive.

The Actin-Related Protein BAF53 Is Essential for Chromosomal Subdomain Integrity

  • Lee, Kiwon;Kim, Ji Hye;Kwon, Hyockman
    • Molecules and Cells
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    • v.38 no.9
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    • pp.789-795
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    • 2015
  • A chromosome territory is composed of chromosomal subdomains. The internal structure of chromosomal subdomains provides a structural framework for many genomic activities such as replication and DNA repair, and thus is key to determining the basis of their mechanisms. However, the internal structure and regulating proteins of a chromosomal subdomain remains elusive. Previously, we showed that the chromosome territory expanded after BAF53 knockdown. Because the integrity of chromosomal subdomains is a deciding factor of the volume of a chromosome territory, we examined here the effect of BAF53 knockdown on chromosomal subdomains. We found that BAF53 knockdown led to the disintegration of histone H2B-GFP-visualized chromosomal subdomains and BrdU-labeled replication foci. In addition, the size of DNA loops measured by the maximum fluorescent halo technique increased and became irregular after BAF53 knockdown, indicating DNA loops were released from the residual nuclear structure. These data can be accounted for by the model that BAF53 is prerequisite for maintaining the structural integrity of chromosomal subdomains.

The Effect of Poria cocos Extract to Inhibit Enterovirus Replication (적복령 추출물의 심근염 유발 엔테로바이러스 증식 억제 효과)

  • Han, Jae-Young;Kim, Jin Hee;Lim, Byung-Kwan
    • Korean Journal of Pharmacognosy
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    • v.47 no.2
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    • pp.137-142
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    • 2016
  • Enterovirus is a common cause of several severe diseases such as myocarditis, hand-foot-mouth disease, and meningitis in children and adult. There are many try to develop new antiviral drug for direct treatment in virus infection. However, synthetic chemical antiviral drug is not working. To overcome this limitation, we examined plant extracts. The antiviral effect of plant extracts was screened by HeLa cell survival assay in coxsackievirus B3 (CVB3) infection. We observed a strong antiviral effect of Poria cocos extract in a dose-dependent manner (1 mg/ml~0.01 mg/ml). P. cocos extract (1 mg/ml) treatment was dramatically decreased virus protease 2A induced eIF4G-I cleavage and virus capsid protein VP1 production. CVB3 positive and negative strand RNA amplification were significantly reduced in P. cocos extract treatment. P. cocos extract completely blocked early time activation of ERK and AKT activity in CVB3 infection. Taken together these data indicate that the treatment of P. cocos extract strongly inhibit CVB3 replication. Poria cocos extract may possible to developed as a therapeutic agent for enterovirus.

Delayed Block Replication Scheme of Hadoop Distributed File System for Flexible Management of Distributed Nodes (하둡 분산 파일시스템에서의 유연한 노드 관리를 위한 지연된 블록 복제 기법)

  • Ryu, Woo-Seok
    • The Journal of the Korea institute of electronic communication sciences
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    • v.12 no.2
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    • pp.367-374
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    • 2017
  • This paper discusses management problems of Hadoop distributed node, which is a platform for big data processing, and proposes a novel technique for enabling flexible node management of Hadoop Distributed File System. Hadoop cannot configure Hadoop cluster dynamically because it judges temporarily unavailable nodes as a failure. Delayed block replication scheme proposed in this paper delays the removal of unavailable node as much as possible so as to be easily rejoined. Experimental results show that the proposed scheme increases flexibility of node management with little impact on distributed processing performance when the cluster size changes.

Enhanced Viral Replication by Cellular Replicative Senescence

  • Ji-Ae Kim;Rak-Kyun Seong;Ok Sarah Shin
    • IMMUNE NETWORK
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    • v.16 no.5
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    • pp.286-295
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    • 2016
  • Cellular replicative senescence is a major contributing factor to aging and to the development and progression of aging-associated diseases. In this study, we sought to determine viral replication efficiency of influenza virus (IFV) and Varicella Zoster Virus (VZV) infection in senescent cells. Primary human bronchial epithelial cells (HBE) or human dermal fibroblasts (HDF) were allowed to undergo numbers of passages to induce replicative senescence. Induction of replicative senescence in cells was validated by positive senescence-associated b-galactosidase staining. Increased susceptibility to both IFV and VZV infection was observed in senescent HBE and HDF cells, respectively, resulting in higher numbers of plaque formation, along with the upregulation of major viral antigen expression than that in the non-senescent cells. Interestingly, mRNA fold induction level of virus-induced type I interferon (IFN) was attenuated by senescence, whereas IFN-mediated antiviral effect remained robust and potent in virus-infected senescent cells. Additionally, we show that a longevity-promoting gene, sirtuin 1 (SIRT1), has antiviral role against influenza virus infection. In conclusion, our data indicate that enhanced viral replication by cellular senescence could be due to senescence-mediated reduction of virus-induced type I IFN expression.

A Design of Update Propagation Algorithm for Replica Consistency of Transaction (트랜잭션의 복제 일관성을 위한 갱신 전파 알고리즘 설계)

  • Lee Byung-Wook
    • Journal of Internet Computing and Services
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    • v.4 no.6
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    • pp.87-93
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    • 2003
  • Data Replication makes distributed system and database system improved in availability and performance. But it is difficult to keep strict consistency in data update. Existing algorithms keep strict consistency, but have problems of cost a great deal and delay time. It is to introduce hybrid update propagation algorithm which permits eager update for original copy and propagates lazy update for other copies. Hybrid update propagation algorithm also permits group update in ownership. This algorithm menages replica version in order to control group update consistency. Consistency and performance is improved by combining eager update and lazy update with group ownership. Simulation shows improvement of transaction throughput and response time depending on application and execution environment.

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A Hot-Data Replication Scheme Based on Data Access Patterns for Enhancing Processing Speed of MapReduce (맵-리듀스의 처리 속도 향상을 위한 데이터 접근 패턴에 따른 핫-데이터 복제 기법)

  • Son, Ingook;Ryu, Eunkyung;Park, Junho;Bok, Kyoungsoo;Yoo, Jaesoo
    • The Journal of the Korea Contents Association
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    • v.13 no.11
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    • pp.21-27
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    • 2013
  • In recently years, with the growth of social media and the development of mobile devices, the data have been significantly increased. Hadoop has been widely utilized as a typical distributed storage and processing framework. The tasks in Mapreduce based on the Hadoop distributed file system are allocated to the map as close as possible by considering the data locality. However, there are data being requested frequently according to the data analysis tasks of Mapreduce. In this paper, we propose a hot-data replication mechanism to improve the processing speed of Mapreduce according to data access patterns. The proposed scheme reduces the task processing time and improves the data locality using the replica optimization algorithm on the high access frequency of hot data. It is shown through performance evaluation that the proposed scheme outperforms the existing scheme in terms of the load of access frequency.