• 제목/요약/키워드: S/key

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Identification of Salmonella pullorum Genomic Sequences Using Suppression Subtractive Hybridization

  • Li, Qiuchun;Xu, Yaohui;Jiao, Xinan
    • Journal of Microbiology and Biotechnology
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    • 제19권9호
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    • pp.898-903
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    • 2009
  • Pullorum disease affecting poultry is caused by Salmonella enterica serovar Pullorum and results in severe economic loss every year, especially in countries with a developing poultry industry. The pathogenesis of S. Pullorum is not yet well defined, as the specific virulence factors still need to be identified. Thus, to isolate specific DNA fragments belonging to S. Pullorum, this study used suppression subtractive hybridization. As such, the genome of the S. Pullorum C79-13 strain was subtracted from the genome of Salmonella enterica serovar Gallinarum 9 and Salmonella enterica serovar Enteritidis CMCC(B) 50041, respectively, resulting in the identification of 20 subtracted fragments. A sequence homology analysis then revealed three types of fragment: phage sequences, plasmid sequences, and sequences with an unknown function. As a result, several important virulence-related genes encoding the IpaJ protein, colicin Y, tailspike protein, excisionase, and Rhs protein were identified that may play a role in the pathogenesis of S. Pullorum.

Survey on the Authentication and Key Management of 802.11s

  • ;이상곤
    • 한국멀티미디어학회:학술대회논문집
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    • 한국멀티미디어학회 2012년도 춘계학술발표대회논문집
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    • pp.89-92
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    • 2012
  • Wireless Mesh Network expanded the capability of the conventional wireless networking by allowing the nodes to operate in proactive mode, reactive mode or the combination of both, the hybrid mode in the multi-hopping nature. By doing so, the links between the nodes become much more robust and reliable because of the number of paths to reach a destination node from a source node can be more than 1 and do not need to rely on the access point (AP) alone to relay the messages. As there may be many possible ways to form an end-to-end link between 2 nodes, the routing security becomes another main concern of the 802.11s protocol. Besides its reliance on the 802.11i for the security measures, 802.11s also includes some new features such as the Mesh Temporal Key (MTK) and the Simultaneous Authentication of Equals (SAE). The authentication and key management (AKM) process of 802.11s were observed in this paper.

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An Improved Biometrics-based Password Authentication Scheme with Session Key Agreement

  • Yang, Hyungkyu
    • International Journal of Internet, Broadcasting and Communication
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    • 제8권3호
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    • pp.50-57
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    • 2016
  • In 2013, Li et al. proposed an improved smart card-based remote user password authentication scheme, and claimed that their scheme not only overcomes security weaknesses of the Chen et al.'s scheme but also is a more user friendly scheme compared with other schemes. In this paper, we analyze the security of Li et al.'s authentication scheme and we show that Li et al.'s authentication scheme is still insecure against the various attacks, such as the off-line password guessing attack, the forgery attack, and the session key generation attack etc. Also, we propose an improved scheme that can resist these security drawbacks of Li et al.'s authentication, even if the secret information stored in the smart card is revealed. As a result of security analysis, the improved scheme is relatively more secure against several attacks than other related schemes in terms of the security.

An Improved Smart Card-based User Authentication Scheme with Session Key Agreement for Telecare Medicine Information System

  • Yang, Hyungkyu
    • International Journal of Internet, Broadcasting and Communication
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    • 제9권3호
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    • pp.35-43
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    • 2017
  • In 2013, Lee-Lie proposed secure smart card based authentication scheme of Zhu's authentication for TMIS which is secure against the various attacks and efficient password change. In this paper, we discuss the security of Lee-Lie's smart card-based authentication scheme, and we have shown that Lee-Lie's authentication scheme is still insecure against the various attacks. Also, we proposed the improved scheme to overcome these security problems of Lee-Lie's authentication scheme, even if the secret information stored in the smart card is revealed. As a result, we can see that the improved smart card based user authentication scheme for TMIS is secure against the insider attack, the password guessing attack, the user impersonation attack, the server masquerading attack, the session key generation attack and provides mutual authentication between the user and the telecare system.

CRYPTANALYSIS OF A DYNAMIC THRESHOLD DECRYPTION SCHEME

  • Kim, Ki-Tae;Lim, Seong-An;Yie, Ik-Kwon;Kim, Kyung-Hee
    • 대한수학회논문집
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    • 제24권1호
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    • pp.153-159
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    • 2009
  • In this paper, we analyze a dynamic threshold decryption scheme proposed by Long et al. It was claimed that the scheme allows to renew the master key, or to add/remove or update a decryption server, without leaking any information on the master key and changing other decryption server's secret keys. We present an attack to Long et al's scheme by using the fact that it renews a decryption server's secret key without changing other decryption server's secret shares.

Cryptanalysis of Multiple-Server Password-Authenticated Key Agreement Schemes Using Smart Cards

  • Lee, Sang-Gon
    • Journal of information and communication convergence engineering
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    • 제9권4호
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    • pp.431-434
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    • 2011
  • Password-based user-authentication schemes have been widely used when users access a server to avail internet services. Multiserver password-authentication schemes enable remote users to obtain service from multiple servers without separately registering with each server. In 2008, Jia-Lun Tsai proposed an improved and efficient password-authenticated key agreement scheme for a multiserver architecture based on Chang-Lee's scheme proposed in 2004. However, we found that Tsai's scheme does not provide forward secrecy and is weak to insider impersonation and denial of service attacks. In this article, we describe the drawbacks of Tsai's scheme and provide a countermeasure to satisfy the forward secrecy property.

한국산 Streblocera 속 (벌 목: 고치벌 과)의 추가종 기록 및 검색표 (Notes on the Korean species of the Genus Streblocera (Insecta: Hymenoptera: Braconidae) with Description of a New Species and a Key to Korean Species)

  • Ser;Deok-Seo Ku
    • Animal Systematics, Evolution and Diversity
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    • 제14권4호
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    • pp.319-325
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    • 1998
  • Streblocera planispina sp. nov.을 신종으로 기재하고, S. macroscapa와 S.dentiscapa를 한국 미기록종으로 보고한다. 한국산 Streblocera 속의 종에 대한 새로운 검색표를 작성하였다.

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일본의 수산정책개혁 중 양식업 정책에 관한 연구 (A Study on Aquaculture Policy among Japan's Fisheries Policy Reform)

  • 송정헌
    • 수산경영론집
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    • 제55권1호
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    • pp.1-20
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    • 2024
  • Among Japan's agriculture, forestry, fisheries and regional revitalization plans established in June 2018, the key matters related to aquaculture include ① a new perspective on the sponge use system for the development of aquaculture and coastal fisheries, ② a comprehensive strategy for growth and industrialization of aquaculture, and ③ expansion of suitable aquaculture areas. There are four countermeasures including ④ research and development trends. In accordance with these key points, the Japanese government established a comprehensive strategy for aquaculture growth and industrialization by strategically setting aquaculture items in consideration of domestic and international demand, establishing a comprehensive strategy from production to sales and export, and then working in earnest to promote the aquaculture industry. This study analyzes environmental changes surrounding aquaculture in Japan and trends in fish farming and marine products, and summarizes the key points of the June 2018 Agriculture, Forestry, Fisheries and Regional Revitalization Plan to suggest measures that can be utilized in Korea's aquaculture policy.

Abridged Region from Escherichia coli Periplasmic Stress Sensor DegS Acts as Plasminogen Activator In Vitro

  • Junpeng, Yan;Ko, Juho;Qi, Yipeng
    • Journal of Microbiology and Biotechnology
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    • 제17권4호
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    • pp.594-599
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    • 2007
  • It is well known that the Escherichia coli inner membrane-bound protease DegS is a periplasmic stress sensor for unfolded outer membrane proteins (OMPs). Previous studies have also shown that the outer membrane protease OmpT activates plasminogen in vitro and this may be exploited by bacteria in the course of pathogenesis. However, there has been no research on the plasminogen activation ability of the important periplasmic protein DegS. Accordingly, in this study, the whole-length and truncated degS genes were separately overexpressed in Escherichia coli, the recombinant proteins purified by affinity chromatography, and their plasminogen activator role tested in vitro. The results suggested that the whole-length DegS was able to activate plasminogen on a plasma plate. The truncated form of DegS (residues 80-345), designated ${\Delta}DegS$, also acted as a plasminogen activator, as confirmed by different assays. The serine protease property of ${\Delta}DegS$ was verified based on the complete inhibition of its enzyme activity by PMSF (phenylmethanesulfonyl fluoride). Therefore, the present results indicate that DegS is a plasminogen activator in vitro.

PRA RESEARCH AND THE DEVELOPMENT OF RISK-INFORMED REGULATION AT THE U.S. NUCLEAR REGULATORY COMMISSION

  • Siu, Nathan;Collins, Dorothy
    • Nuclear Engineering and Technology
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    • 제40권5호
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    • pp.349-364
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    • 2008
  • Over the years, probabilistic risk assessment (PRA) research activities conducted at the U.S. Nuclear Regulatory Commission (NRC) have played an essential role in support of the agency's move towards risk-informed regulation. These research activities have provided the technical basis for NRC's regulatory activities in key areas; provided PRA methods, tools, and data enabling the agency to meet future challenges; supported the implementation of NRC's 1995 PRA Policy Statement by assessing key sources of risk; and supported the development of necessary technical and human resources supporting NRC's risk-informed activities. PRA research aimed at improving the NRC's understanding of risk can positively affect the agency's regulatory activities, as evidenced by three case studies involving research on fire PRA, human reliability analysis (HRA), and pressurized thermal shock (PTS) PRA. These case studies also show that such research can take a considerable amount of time, and that the incorporation of research results into regulatory practice can take even longer. The need for sustained effort and appropriate lead time is an important consideration in the development of a PRA research program aimed at helping the agency address key sources of risk for current and potential future facilities.