• Title/Summary/Keyword: replication strategy

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A Dynamic Data Grid Replication Strategy Considering Internet Architecture (인터넷 구조를 고려한 동적 데이터 그리드 복제 정책)

  • Kim, Jun-Sang;Lee, Won-Joo;Jeon, Chang-Ho
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.07a
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    • pp.64-66
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    • 2005
  • 인터넷은 수많은 AS(Autonomous System)들로 이루어져 있으며, 각 AS들은 ISP(Internet Service Provider)를 통하여 인터넷에 접속한다. AS와 ISP 사이에는 계층성과 네트워크 속도 차에 따른 대역폭 병목현상이 존재한다. 이러한 인터넷의 물리적 네트워크 구조는 그리드 환경에서 데이터 접근시간에 가장 큰 영향을 미친다. 기존의 데이터 그리드 복제 정책은 물리적 네트워크의 구조를 고려하지 못하였기 때문에 실제 인터넷 환경에서 최적의 성능을 얻지 못하는 문제점이 있었다. 본 논문에서는 실제 인터넷의 물리적 네트워크 구조를 고려한 데이터 그리드 복제 정책을 제안한다. 이 복제 정책은 ISP와 AS 단위로 복사본을 유지하여 병목현상을 최소화함으로써 전체적인 데이터 그리드의 성능을 향상시킨다.

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A Peer-to-Peer based Replication Strategy for Data Grid (데이터 그리드를 위한 Peer-to-Peer기반 복제 정책)

  • 오상원;이원주;전창호
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.10a
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    • pp.49-51
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    • 2004
  • 데이터 그리드를 위한 기존의 복제 정책은 계층적 구조를 기반으로 하고 있기 때문에 상위계승에서 하위계층으로만 데이터를 복제할 수 있어 비효율적이다. 따라서 본 논문에서는 기존 데이터 그리드의 계층적 구조에 P2P(Peer-to-Peer)시스템을 적용하여 효율적으로 복제본을 유지할 수 있는 새로운 복제 정책을 제안한다. 이 정책의 특징은 클라이언트 노드의 저장 공간 일정 부분을 임계 구역(critical section)으로 지정하여 데이터 조작을 방지함으로써 클라이언트 노드도 데이터 복제본을 저장할 수 있는 기능을 가지도록 한 것이다. 따라서 계층적 구조에서 상위 계층뿐만 아니라 동일 계층 또는 클라이언트 노드들 간의 데이터 전송이 가능하기 때문에 데이터 그리드의 성능을 향상시킬 수 있다.

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Transparent Replica Strategy for Fault-Masking in Real-Time Distribution System (실시간 분산시스템의 결함 마스킹을 위한 투명성 부가 중복 전략)

  • 김분희;김영찬
    • Proceedings of the Korean Information Science Society Conference
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    • 2002.10c
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    • pp.340-342
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    • 2002
  • 결함허용은 어떠한 시스템 요소에 결함이나 오류가 발생하더라도 시스템이 정상적으로 동작하게 하는 방안으로써 실시간 분산 시스템에서 피 효용성이 극대화된다. 본 연추는 실시간 분산 시스템의 결함 허용 기법 중 시간 제약성 측면에서 강한 여분기반 결함허용 기법을 수용한다. 이 기법의 구성 요소인 어플리케이션 서버는 그 상태가 결정적(deterministic)이냐 비결정적(nondeterministic)이냐에 따라 그 처리 기법을 달리하고 있다. 그 중 SAR(Semi-Active Replication)이 자원 활용도 측면에서 그 효율성 증명된바 있다. 본 논문에서는 SAR의 단점인 응답시간 지연문제와 클라이언트 측면에서의 결함 마스킹(fault-masking) 문제를 해결한 구조를 제안한다.

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Adaptive Data Replication Strategy using data access history in DataGrid (데이터 접근 기록 정보를 이용한 적응적 데이터 복제 기법 제안)

  • Sung, GiMun;Lee, DongWoo;Choi, Jihyun;Ramakrishna, R.S.
    • Proceedings of the Korea Information Processing Society Conference
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    • 2004.05a
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    • pp.937-940
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    • 2004
  • 프로세서 자원, 데이터 저장장치 자원을 제공하면서 가상기관(Virtual Organization)을 구성하는 각 사이트는 사용할 수 있는 네트윅 자원이 한정된 상황에서 애플리케이션 처리량을 극대화하는 최적화된 데이터그리드 시스템을 기대한다. 본 논문에서는 크기가 제한적이며 지리적으로 분산된 데이터 저장공간에서 적응적 데이터 복제 기법을 제안하고 Replica의 지리적 분배를 위한 평가 모델을 제안한다. 이를 위해 논리 시간 데이터 접근 기록 및 통계를 적용하여 복제할 파일들을 구분 하는 이산적 결정 모델을 제안하고 삭제할 Replica 결정에 논리 시간 접근 기록을 적용한다.

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Multiple Alternating Immunizations with DNA Vaccine and Replication-incompetent Adenovirus Expressing gB of Pseudorabies Virus Protect Animals Against Lethal Virus Challenge

  • Kim, Seon-Ju;Kim, Hye-Kyung;Han, Young-Woo;Aleyas, Abi G.;George, Junu A.;Yoon, Hyun-A;Yoo, Dong-Jin;Kim, Koan-Hoi;Eo, Seong-Kug
    • Journal of Microbiology and Biotechnology
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    • v.18 no.7
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    • pp.1326-1334
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    • 2008
  • The prime-boost vaccination with DNA vaccine and recombinant viral vector has emerged as an effective prophylactic strategy to control infectious diseases. Here, we compared the protective immunities induced by multiple alternating immunizations with DNA vaccine (pCIgB) and replication-incompetent adenovirus (Ad-gB) expressing glycoprotein gB of pseudorabies virus (PrV). The platform of pCIgB-prime and Ad-gB-boost induced the most effective immune responses and provided protection against virulent PrV infection. However, priming with pCIgB prior to vaccinating animals by the DNA vaccine-prime and Ad-boost protocol provided neither effective immune responses nor protection against PrV. Similarly, boosting with Ad-gB following immunization with DNA vaccine-prime and Ad-boost showed no significant responses. Moreover, whereas the administration of Ad-gB for primary immunization induced Th2-type-biased immunity, priming with pCIgB induced Th1-type-biased immunity, as judged by the production of PrV-specific IgG isotypes and cytokine IFN-$\gamma$. These results indicate that the order and injection frequency of vaccine vehicles used for heterologous prime-boost vaccination affect the magnitude and nature of the immunity. Therefore, our demonstration implies that the prime-boost protocol should be carefully considered and selected to induce the desired immune responses.

Cognitive Individual Differences and L2 Learners' Processing of Korean Subject-Object Relative Clauses (인지능력의 개별차와 한국어 학습자의 주격-목적격 관계절 프로세싱)

  • Goo, Jaemyung
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.8 no.6
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    • pp.493-503
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    • 2018
  • The present study is a conceptual replication of O'Grady, Lee, and Choo's (2003) earlier study designed to investigate two hypotheses (linear distance hypothesis vs. structural distance hypothesis) in relation to L2 Korean learners' processing of Korean subject and object relative clauses (RCs) in a scholarly attempt to explicate Keenan and Comrie's (1977) Noun Phrase Accessibility Hierarchy (NPAH). In addition, the current study is intended to explore any potential role of working memory capacity (WMC) in the processing of Korean subject and/or object RCs. Chinese-speaking learners of Korean taking a language course offered at a local university in Korea participated in this experimental study. Among those recruited, only 23 learners completed the experimental tasks appropriately according to the specific instructions provided on each task, and thus, subsequent statistical analyses were conducted on their data. Fifteen Korean NSs were also recruited for the control group. Two experimental tasks were administerd to the participants: one picture selection task containing the same test items used in O'Grady et al.'s study to measure their processing of subject-object RCs and an operation span (OSPAN) task to measure their WMC. Somewhat differently from O'Grady et al.'s findings, the participating Chinese learners of Korean performed significantly better on object RCs than on subject RCs, seemingly lending support to the linear distance hypothesis. Further analyses, however, suggested that the results in favor of, or relative ease of processing, object relative clauses were due, most likely, to the learners' excessive use of the canonical sentence strategy, which also led to nonsignificant correlations between WMC and learner performance on the picture selection task.

The Mechanism of the Influence of Advanced Selling on Consumer Choice (사전예약을 통한 구매결정이 소비자의 선택에 미치는 영향력의 작동원리에 관한 실증연구)

  • Kim, Kyung-Ho;Lee, Hyoung-Tark;Seo, Heon-Joo
    • Journal of Distribution Science
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    • v.14 no.6
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    • pp.81-87
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    • 2016
  • Purpose - In recent, a research finds that advanced selling can influence a consumer's choice(Kim et al., 2013). Advanced selling is defined as the new product launching strategy which company allows consumers to preorder new product before its release(Chu & Zhang, 2011). Prior researches have focused on the benefits of advanced selling(e.g., information gathering for demand prediction, an advantage for pricing strategy, and so on) for companies using this strategy(Chen, 2001; Chu & Zhang, 2011; Li & Zhang, 2013; Tang et al., 2004; Xie & Shugan, 2009). However, Kim et al.(2013) find it can also influence a consumer's choice. In detail, they suggest that when consumers use advanced selling, they are likely to prefer high-performance options rather than low-price options based on construal level theory(Trope & Liberman, 2003). In this paper, we tried to expand the prior researches for finding the mechanism of the influence of advanced selling on a consumer's choice. The purpose of this research is to test the mediating effect on the influence of advanced selling. Research design, data, and methodology - To find the mechanism of the influence of advanced selling, we designed an experiment for testing mediation effect. we recruited 93 students from a university. We assigned participants into one of two groups using randomization method. The participants with each group were given a scenario describing the sales strategy. Finally, they made a choice between high-performance option and low-price option. Sequentially, they also responded some questions for testing mediation effect. Results - First, we replicated prior research to test the influence of advanced selling. As a result, we could find that consumers prefer the high-performance option when they preorder it to purchase at the time of consumption. Thus, the replication result is the same as prior research. Second, we tested that advanced selling can influence the perception of temporal distance. The results confirmed that consumers perceived longer temporal distance in advanced selling condition(β = 1.575, SE = 0.272, p < 0.001). Third, we predicted that temporal distance can increase the importance of desirable attributes and decrease the importance of feasible attributes. The results suggested that temporal distance decreased significantly the importance of attributes related to feasibility(β = -0.19, SE = 0.07, p < 0.01), however, it had non-significant effect on increasing the importance of desirable attributes. Finally, we used Sobel-test for testing mediation effect, and it confirmed that the importance of feasible attributes had mediating role of the influence of advanced selling(Sobel test statistic = -2.110, SE = 0.111, p < 0.05). Conclusions - In this paper, we tried to find the mechanism of the influence on advanced selling from a consumer's choice. With an experiment, we confirmed that the importance of feasible attributes could mediate the effect on advanced selling. Therefore, we suggested some theoretical and practical contributions from this research. Finally, we discussed research limitations and suggested future research topics.

The Basis of Different Sensitivities of Ovarian Cancer Cells to the Recombinant Adenoviral Vector System Containing a Tumor-Specific L-plastin Promoter and E. coli Cytosine Deaminase Gene as a Transcription Unit

  • Chung, In-Jae
    • Biomolecules & Therapeutics
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    • v.17 no.2
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    • pp.138-143
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    • 2009
  • We have reported previously on a replication incompetent recombinant adenoviral vector, AdLPCD, in which the expression of cytosine deaminase gene (CD) is driven by the tumor-specific L-plastin promoter. AdLPCD vector had been evaluated for its efficacy of chemosensitization of ovarian cancer cells to 5-FC. In spite of the fact that ovarian cancer cells, i.e., OVCAR-3 and SK-OV-3, are capable for adenoviral transduction judged by LacZ reporter gene analysis, two cell lines demonstrated quite different sensitivities toward AdLPCD/5-FC system. In OVCAR-3 cells, infection of AdLPCD followed by exposure to 5-FC resulted in the suppression of cell growth with statistical significance. On the other hand, SK-OV-3 cells were more resistant to the CD/5-FC strategy compared with OVCAR-3 cells under the same condition. The object of study was to investigate factors that would determine the sensitivity to AdLPCD/5-FC. We evaluated conversion rate of 5-FC to 5-FU after infection of AdLPCD by HPLC analysis, $IC_{50}$ of 5-FU, the expression level of integrin receptors i.e., ${\alpha}v{\beta}3$ and ${\alpha}v{\beta}5$, and status of p53 in OVCAR-3 and SK-OV-3 cells. The results indicated that OVCAR-3 cells have few favorable features compared with SK-OV-3 cells to be more effective to the AdLPCD/5-FC strategy; higher level of ${\alpha}v{\beta}5$ integrin, higher rate of conversion of 5-FC into 5-FC, and lower $IC_{50}$ of 5-FU. The results suggest that the replacement of 5-FU with CD/5-FC in combination chemotherapy would be less toxic and much greater cytotoxicity than the conventional combination chemotherapy in some patients.

Comparative Analysis of Intracellular Trans-Splicing Ribozyme Activity Against Hepatitis C Virus Internal Ribosome Entry Site

  • Ryu Kyung-Ju;Lee Seong-Wook
    • Journal of Microbiology
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    • v.42 no.4
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    • pp.361-364
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    • 2004
  • Internal ribosome entry site (IRES) of the hepatitis C virus (HCV) is known to be essential for HCV replication and most conserved among HCV variants. Hence, IRES RNA is a good therapeutic target for RNA-based inhibitors, such as ribozymes. We previously proposed a new anti-HCV modulation strategy based on trans-splicing ribozymes, which can selectively replace HCV transcripts with a new RNA that exerts anti-HCV activity. To explore this procedure, sites which are accessible to ribozymes in HCV IRES were previously determined by employing an RNA mapping method in vitro. In this study, we evaluate the intracellular accessibility of the ribozymes by comparing the trans-splicing activ­ities in cells of several ribozymes targeting different sites of the HCV IRES RNA. We assessed the intra­cellular activities of the ribozymes by monitoring their target-specific induction degree of both reporter gene activity and cytotoxin expression. The ribozyme capable of targeting the most accessible site iden­tified by the mapping studies then harbored the most active trans-splicing activity in cells. These results suggest that the target sites predicted to be accessible are truly the most accessible in the cells, and thus, could be applied to the development of various RNA-based anti-HCV therapies.

Viral Inhibition of PRR-Mediated Innate Immune Response: Learning from KSHV Evasion Strategies

  • Lee, Hye-Ra;Choi, Un Yung;Hwang, Sung-Woo;Kim, Stephanie;Jung, Jae U.
    • Molecules and Cells
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    • v.39 no.11
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    • pp.777-782
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    • 2016
  • The innate immune system has evolved to detect and destroy invading pathogens before they can establish systemic infection. To successfully eradicate pathogens, including viruses, host innate immunity is activated through diverse pattern recognition receptors (PRRs) which detect conserved viral signatures and trigger the production of type I interferon (IFN) and pro-inflammatory cytokines to mediate viral clearance. Viral persistence requires that viruses co-opt cellular pathways and activities for their benefit. In particular, due to the potent antiviral activities of IFN and cytokines, viruses have developed various strategies to meticulously modulate intracellular innate immune sensing mechanisms to facilitate efficient viral replication and persistence. In this review, we highlight recent advances in the study of viral immune evasion strategies with a specific focus on how Kaposi's sarcoma-associated herpesvirus (KSHV) effectively targets host PRR signaling pathways.