• 한국정보시스템학회지:정보시스템연구
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• 제15권1호
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• pp.145-168
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• 2006

Current computer viruses are one of the most serious problems in information age due to their potential demage and impact on use of information systems. To make the problem worse, virus development technology has been advanced rapidly, and use of network systems has expanded widely. Therefore computer viruses are much more complex and use of anti-virus software(AV S/W) is not enough to prrevent virus incidents. It implies that computer viruses as well as other information security matters are not solely a technical problem but also a managerial one. This study emphasized on computer virus controls from managerial perspective of information security and investigated factors influencing the effectiveness of computer virus controls. Organization's comprehensive security policies provide guidelines on how organization or individual can protect themselves from computer viruses. Especially, user's education has positive impact on user's security related characteristics. Based on the analysis of research model using structural equation modeling technique, security policies were influencing security controls and improving user's computer viruses related awareness. Also security controls had positive impact on security effectiveness. However, no significant relationship was found between user's security related characteristics and security effectiveness.

• The Plant Pathology Journal
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• 제18권5호
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• pp.244-250
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• 2002

Grapevine leafroll-associated 3 virus (GLRaV-3) and Grapevine fanleaf virus (GFLV) are important viral diseases of grapevine in the world. In this study, the most reliable woody indicator plants were selected for virus indexing. Two grapevines, LN33 (Couderc 1613x vitis berlandieri) and Vitis riparia Gloire, were selected for CLRaV-3 and CFLV graft indexing, respectively. The specific characteristics of Closterovirus isolated from grapevines cultivated in Korea were identified. filamentous virus-like particles only existed in the phloem parenchyma cell. In particular, the vesiculation of mitochondria was observed. This mitochondrial vesicu-lation was considered to be one of the most reliable cytopathic features of Closterovirus. During observation of GFLV-infected Chenopodium quinoa sections, virus-like particles arranged consistently were found forming several layers in cytoplasm. Moreover, virus-like particles in tubules were observed and were associated with plasmodesmata in cytoplasm. This is the first report on cytopathological characteristics of Closterovirus and Nepovirus identified from grapevines in Korea.

• 대한수의학회지
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• 제39권4호
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• pp.751-759
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• 1999

Plaque characteristics of porcine reproductive and respiratory syndrome (PRRS) virus isolates were examined using MARC-145 line cells. The plaque morphology of PRRS virus isolates was variable in size and heterogenic in population. Upon serial passages of the PRRS virus isolates on MARC-145 tells, heterogeneity was maintained but numbers of the large plaque size virus were increased with certain isolates. A PRRS virus isolate with variable plaque sizes was subcloned into 2 populations : small plaque ($H_S$) and large plaque ($H_L$) viruses. Growth kinetics of the subclones were then determined in MARC-145 cells, and production of the structural polypeptides was analyzed by SDS-PAGE. In a comparison of the growth kinetics, the $H_S$ virus showed higher infectivity titers during the first 48 hours but slower to reach the peak titier than $H_L$ virus did. In a nucleotide sequence comparison, differences of 4 nucleotides in open reading frames 5-6 gene were found between $H_S$ and $H_L$ viruses. Both the $H_S$ and $H_L$ clones produced 5 polypeptide bands with molecular weights of 15, 19, 26, 36 and 42 kD. The 5 bands were detected at 48 hours postinoculation (PI) with antisera to $H_L$ and another large plaque virus ($W_L$) and at 72 hours PI with $H_S$ virus antiserum. The present results demonstrate differences of biologic and molecular characteristics between the two PRRS virus plaque clones.

• 융합보안논문지
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• 제5권1호
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• pp.53-62
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• 2005

virus 방역 체계 관리는 network infra 구조관리, traffic 소통경로관리, 방역 zone 설정, gateway구간 방역관리이다. 본 논문은 일반적인 방역체계 구조의 성격과 취약점을 진단하고 이를 개선할 수 있는 대책으로서 개선된 방역체계를 설계하였다. 또한 설계된 방역체계와 configuration, mechanism하에서는 어느 정도의 개선효과 나타나고 있는지 분석하였다. 개선된 다단계 방역체계 하에서는 gateway 단계에서 불필요한 mail을 걸러줌으로서 server에 주는 부하는 감소하며 virus wall상의 CPU 부하의 감소와 virus 치료율의 상승으로 송신 적체 건수는 감소하고 시스템 process수는 증대하고 있다.

• 한국사이버테러정보전학회:학술대회논문집
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• 한국사이버테러정보전학회 2004년도 제1회 춘계학술발표대회
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• pp.187-198
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• 2004

virus방역 체계 관리는 network infra구조관리, traffic소통경로관리. 방역 zone설정, gateway구간 방역관리이다. 본 논문은 일반적인 방역체계 구조의 성격과 취약점을 진단하고 이를 개선할 수 있는 대책으로서 개선된 방역체계를 설계하였다. 또한 설계된 방역체계와 configuration, mechanism하에서는 어느 정도의 개선효과 나타나고 있는지 분석하였다. 개선된 다단계 방역체계 하에서는 gateway 단계에서 불필요한 mail을 걸러주므로서 server에 주는 부하는 감소하며 virus wall상의 CPU부하의 감소와 virus 치료율의 상승으로 송신 적체 건수는 감소하고 시스템 process수는 증대하고있다.

• 한국실내디자인학회논문집
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• 제18권3호
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• pp.102-113
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• 2009

The SARS virus began to appear and spread in North America and Southeast Asia in the early 2000' s, infecting and harming many people. In the process of examining the causes for the virus, studies on the airborne SARS virus and the way it spread were carried out mainly in the medical field. In the field of architecture, studies were done on the diffusion of air pollutants in buildings using gases such as $CO_2$, $N_2O$, or $SF_6$, but research on virus diffusion was limited. There were also explanations of only the diffusion process without accurate information and discussion on virus characteristics. The aim of this study is to analyze the physical characteristics of airborne virus, consider the possibility of using coupled analysis model and tracer gas for analyzing virus diffusion in building space and, based on reports of how the infection spread in a hospital where SARS patients were discovered, analyze infection risk using tracer gas density and also diffusion patterns according to the location, shape, and volume of supply diffusers and exhaust grilles. This paper can provide standards and logical principles for evaluating various alternatives for making decisions on vertical or horizontal ward placement, air supply and exhaust installation and air volumes in medium or high story medical facilities.

• Journal of Microbiology
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• 제40권1호
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• pp.1-10
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• 2002

At the dose of 1000 p.f.u. per mouse,100% mortality occurred in mice inoculated with wild-type pseudorabies virus (PrV). In contrast, upon stable deletion of 10 bp nucleotides at the Bsrl site within the TK gene, PrV was rendered to be completely apathogenic. The deletion also caused the virus to be less capable of replicating in respiratory as well as in nervous system tissues. Although animals were exposed to high titers of TK-deleted PrVs, the virus failed to replicate to a high titer as compared to the pathogenic parental virus. In contrast to previous studies the deletion in the TK gene did not prevent the virus from establishing latency. Upon immunosuppression, the latent virus? however, reactivated but replicated at low titers. Interestingly, TK-deleted virus established latency and reactivation, that are occurred only in trigeminal ganglia and the cerebrums and no other tissues involved. Following reactivation, there was no indication of virus shedding in respiratory tissues as confirmed by virus isolation and polymerase chain reaction (PCR) technique targeting at the gB gene of PrV, The non-pathogenic virus with non-shedding characteristics, upon reactivation of the latent virus, would be the important feature of a live virus vaccine candidate.

• Journal of Microbiology and Biotechnology
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• 제29권8호
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• pp.1184-1192
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• 2019

The influenza A virus is a highly infectious respiratory pathogen that sickens many people with respiratory disease annually. To prevent outbreaks of this viral infection, an understanding of the characteristics of virus-host interaction and development of an anti-viral agent is urgently needed. The influenza A virus can infect mammalian species including humans, pigs, horses and seals. Furthermore, this virus can switch hosts and form a novel lineage. This so-called zoonotic infection provides an opportunity for virus adaptation to the new host and leads to pandemics. Most influenza A viruses express proteins that antagonize the antiviral defense of the host cell. The non-structural protein 1 (NS1) of the influenza A virus is the most important viral regulatory factor controlling cellular processes to modulate host cell gene expression and double-stranded RNA (dsRNA)-mediated antiviral response. This review focuses on the influenza A virus NS1 protein and outlines current issues including the life cycle of the influenza A virus, structural characterization of the influenza A virus NS1, interaction between NS1 and host immune response factor, and design of inhibitors resistant to the influenza A virus.

• The Plant Pathology Journal
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• 제28권4호
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• pp.433-438
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• 2012

Dinoflagellates are considered one of the most abundant and diverse groups of marine microplankton and viruses are recognized as one of the significant factors affecting the plankton dynamics. Here, we report basic characteristics of a new dinoflagellate-infecting virus, Heterocapsa pygmaea DNA virus (HpygDNAV) which infects a toxic dinoflagellate, H. pygmaea. HpygDNAV is a polyhedral large virus (ca. 160-170 nm in diameter) propagating in its host's cytoplasm. Because of the virion size, appearance in thin sections, and propagation characteristics, HpygDNAV is assumed to harbor a large double-stranded DNA genome; i.e., HpygDNAV is most likely a nucleocytoplasmic large DNA virus (NCLDV) belonging to the family Phycodnaviridae. Its infectivity is strain-specific, rather than species-specific, as is the case for other algal viruses. The burst size and latent period are estimated to be roughly 100-250 infectious units $cell^{-1}$ and < 96 h, respectively.

• Journal of Microbiology
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• 제33권2호
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• pp.154-159
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• 1995

SH-14, a novel killer strain of Ustilago maydis was isolated in Korea. It has been reported in other papers that the toxin specificity and double-stranded RNA pattern of SH-14 strain were different from other laboratory strains. In this paper, we analyzed the biochemical characteristics of U. maydis SH-14 virus. Three distinctive peaks were isolated from CsCl density gradient, designated as top (T), intermediate (I) and bottom (B) components. We found that the densities of each components, 1.285, 1.408 g/cm$\^$3/, respectively, are very similar to those of other strains. As previously reported by the analysis of dsRNA in each component, the dsRNA segments are separately encapsidated. Capsid protein of SH-14 virus consists of two proteins about 70 Kd shown by SDS-PAGE analysis. Electron microscopic examination of the virus particles revealed that UmV particles are very similar in size and morphology to all isolates as well as all lab-strains. In order to test immunological cross reactivity of UmV, werstern bolt analysis was carriedout with antiserum against A8 virus. All capsid protein had positive reaction against A8 antibody which indicated that UmV are immunologically cross-reactive with all isolates from Korea. The results presented in this paper may show that UmV isolated from SH-14 strain has very similar biochemical characteristics to those of other UmV. However, the difference in the toxin specificity and the molecular weight of toxin protein from the SH-14 strain has us to conclude that U. maydis SH-14 strain is a new killer type.