• 제목/요약/키워드: key protection

검색결과 933건 처리시간 0.033초

Nonexistence and non-decoupling of the dissipative potential for geo-materials

  • Liu, Yuanxue;Zhang, Yu;Wu, Runze;Zhou, Jiawu;Zheng, Yingren
    • Geomechanics and Engineering
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    • 제9권4호
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    • pp.531-545
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    • 2015
  • Two fundamental issues exist in the damage theory of geo-material based on the concept of thermodynamics: existence or nonexistence of the dissipation potential, and whether the dissipation potential could be decoupled into a damage potential and a plastic one or not. Thermodynamics theory of elastoplastic damage assumes the existence of dissipation potential, but the presence of dissipation potential is conditional. Based on the dissipation inequality in accord with the second law of thermodynamics, the sufficient and necessary conditions are given for the existence of the dissipation potential separately in total and incremental forms firstly, and proved strictly in theory. With taking advantage of the basic mechanical properties of geo-materials, the nonexistence of the dissipative potential is verified. The sufficient and necessary conditions are also given and proved for the decoupling of the dissipation potential of geo-materials in total and incremental forms. Similarly, the non-decoupling of the dissipation potential has also been proved, which indicates the dissipation potential of geo-materials in total or incremental forms could not be decoupled into a dissipative potential for plasticity and that for damage respectively. The research results for the fundamental issues in the thermodynamics theory of damage will help establish and improve the theoretic basis of elastoplastic damage constitutive model for geo-materials.

Determination of Herbicide Propisochlor in Soil, Water and Rice by Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) Method Using by UPLC-ESI-MS/MS

  • Wu, Xiaohu;Xu, Jun;Liu, Xingang;Dong, Fengshou;Wu, Yanbing;Zhang, Ying;Zheng, Yongquan
    • Bulletin of the Korean Chemical Society
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    • 제34권3호
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    • pp.917-921
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    • 2013
  • A simple, quick and reliable analytical method for the confirmation and quantification of propisochlor was developed. The propisochlor was extracted from water, soil and rice (stalks, rice and hull) matrices using acetonitrile, and cleaned up with primary secondary amine and determined by UPLC-MS/MS. The LODs of propisochlor ranged from 0.03 ${\mu}g/kg$ to 0.12 ${\mu}g/kg$, while the LOQs ranged from 0.1 ${\mu}g/kg$ to 0.4 ${\mu}g/kg$ in different matrixes. The mean recoveries of propisochlor at three levels (0.005, 0.01 and 0.05 mg/kg) were in the range of 73.7-94.9% with intra-day relative standard deviations (RSD) of 1.1-13.9% and inter-day $RSD_R$ of 3.3-12.7%. This method is suitable for routine analysis of propisochlor under field conditions. The half-lives of propisochlor in rice stalks, water and soil were 1.7, 1.5 and 2.3 days in Hunan, 5.7, 1.0 and 1.9 days in Anhui and 4.8, 1.0 and 3.1 days in Guangxi.

Nonexistence and non-decoupling of the dissipative potential for geo-materials

  • Liu, Yuanxue;Zhang, Yu;Wu, Runze;Zhou, Jiawu;Zheng, Yingren
    • Geomechanics and Engineering
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    • 제9권5호
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    • pp.569-583
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    • 2015
  • Two fundamental issues exist in the damage theory of geo-material based on the concept of thermodynamics: existence or nonexistence of the dissipation potential, and whether the dissipation potential could be decoupled into a damage potential and a plastic one or not. Thermodynamics theory of elastoplastic damage assumes the existence of dissipation potential, but the presence of dissipation potential is conditional. Based on the dissipation inequality in accord with the second law of thermodynamics, the sufficient and necessary conditions are given for the existence of the dissipation potential separately in total and incremental forms firstly, and proved strictly in theory. With taking advantage of the basic mechanical properties of geo-materials, the nonexistence of the dissipative potential is verified. The sufficient and necessary conditions are also given and proved for the decoupling of the dissipation potential of geo-materials in total and incremental forms. Similarly, the non-decoupling of the dissipation potential has also been proved, which indicates the dissipation potential of geo-materials in total or incremental forms could not be decoupled into a dissipative potential for plasticity and that for damage respectively. The research results for the fundamental issues in the thermodynamics theory of damage will help establish and improve the theoretic basis of elastoplastic damage constitutive model for geo-materials.

Three New Loci of Insertion Element IS1112 in Chinese Strains of Xanthomonas oryzae pv. oryzae

  • Xie, Jiajian;Wang, Xifeng;Li, Feiwu;Peng, Yufa;Zhou, Guanghe
    • Journal of Microbiology
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    • 제45권3호
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    • pp.219-226
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    • 2007
  • Insertion sequence IS1112 is a repetitive element with a relatively high number of copies in Xanthomonas oryzae pv. oryzae (Xoo), the causal agent of bacterial blight of rice (Oryza sativa L.). Three new loci of IS1112 were identified in seven Chinese strains of Xoo using a single oligonucleotide primer J3; 5'-GCTCA GGTCAGGTGGCCTGG-3' by insertion-sequence-based polymerase chain reaction (IS-PCR). Among the three new loci of IS1112, two were located in the open-reading frame region of genes fhuA and cirA, which encode TonB-dependent receptors, and the third in ISXo2, another type of insertion sequence in Xoo genome. Three variants of IS1112 were identified in those three loci based on their sequence similarities: two were identical to IS1112a and IS1112b, reported in strain PXO86 from the Philippines, while the third was a new member of IS1112, defined as IS1112d. Inserting IS1112 in gene fhuA caused three bases, GGT, to be duplicated at the target site, but inserting it in gene cirA did not cause any duplication in the target site. The diversity of IS1112 sequence and insertion loci in Xoo genome and their potential effects are discussed.

MP3 저작권 보호를 위한 AOD 시스템의 설계 (Design of AOD System for MP3 Copyright Protection)

  • 김영준;김태윤
    • 정보처리학회논문지D
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    • 제9D권2호
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    • pp.323-328
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    • 2002
  • 최근 초고속 통신망을 이용한 인터넷의 대중화와 더불어 인터넷을 기반으로 하는 전자상거래가 활발해지고 있다. 특히 인터넷을 통한 MP3 데이터 등의 멀티미디어 컨텐츠의 유통은 많은 연구의 대상이 되고 있다. 하지만 기존의 AOD(Audio On Demand) 시스템들은 실질적인 불법 복제방지와 저작권 보호에 미흡한 단점이 있다. 따라서 본 논문에서는 공개키 기반 구조(PKI: Public Key Infrastructure)에 기초하여 실질적인 불법복제방지와 저작권을 보호하는 AOD 시스템을 제안한다. 제안된 기법은 사용자의 공개키를 이용하여 MP3 데이터를 전송함으로써 전송 도중 제 3자로부터의 공격에 대응할 수 있고, 정당한 사용자 외에는 MP3 데이터를 사용하지 못하도록 함으로써 사용자와 판매자의 권리를 보장한다.

쿠키보호기능을 제공하는 안전한 웹 시스템의 설계 및 구현 (Design and Implementation of Secure Web System with Cookies Protection Function)

  • 최은복;최향창;이형옥
    • 한국멀티미디어학회논문지
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    • 제7권7호
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    • pp.934-943
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    • 2004
  • 본 논문에서는 웹에서 사용되는 쿠키를 안전하게 사용할 수 있도록 쿠키보호를 위해 쿠키 보호키 관리 시스템을 두고 사용자별로 다른 쿠키 보호키를 유지하게 함으로써, 쿠키 사용에 따른 사용자 정보의 무결성, 비밀성, 사용자 인증 서비스를 제공한다. 또한 웹 기술을 이용할 경우 노출된 URL을 이용해 내부 문서의 위치를 추측하고 접근하는 것을 방지하기 위해 URL을 노출시키지 않는 방법을 제시하였다. 본 시스템은 기업의 인트라넷에 적용함으로써 공격자에게 쉽게 정보 노출이 발생하는 취약한 쿠키의 안전함을 제공하고 내부사용자에 대한 내부문서 유출 문제를 최소화할 수 있을 것이다.

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상가권리금 법제화의 문제점과 개선방안 연구 (Study on Problems and Its Improvements of Legislation for Shop Key Money)

  • 노한장
    • 한국콘텐츠학회논문지
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    • 제15권11호
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    • pp.410-421
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    • 2015
  • 본 연구의 목적은 상가권리금 법제화(2015.5.12.)의 내용을 구체적으로 검토하고, 임차인이 권리금을 회수하는 과정에서 실질적인 보호가 이루질 수 있도록 효과적인 개선방안을 강구하는 데 있다. 이러한 관점에서 본 연구는 다음과 같은 몇 가지 입법론을 제시하고자 한다. 우선, 개정된 상가건물임대차보호법상 서로 상충되는 '권리금' 및 '권리금 계약'의 정의규정은 혼란을 야기할 수 있을 뿐만 아니라, 임차인의 권리금회수보호라는 측면에서도 문제가 있으므로 양자를 일치시켜야 한다. 다음으로, 일정한 요건을 갖춘 경우 권리금 자체의 대항력을 인정하여 임차인의 권리금 회수보호를 강화할 필요가 있다. 또한, 임대인의 임차인 권리금 회수 방해행위와 관련된 모호한 규정들을 명확하게 정비하여야 하며, 권리금 회수방해로 인한 손해배상에 대한 입증책임이 누구에게 있는지를 명확히 정하여야 한다. 마지막으로, 국토교통부 장관으로 하여금 지역별 상권별 업종별 표준권리금 수준을 조사하여 고시하도록 의무화하여야 한다.

스캔 설계된 AES 코아의 효과적인 비밀 키 보호 기술 (An Efficient Secrete Key Protection Technique of Scan-designed AES Core)

  • 송재훈;정태진;정혜란;김화영;박성주
    • 대한전자공학회논문지SD
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    • 제47권2호
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    • pp.77-86
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    • 2010
  • 본 논문은 Advanced Encryption Standard(AES) 암호화 코아가 내장된 System-on-a-Chip(SoC)의 스캔 기반 사이드 채널 공격에 의해 발생될 수 있는 비밀 키 정보 누출 방지를 위한 효과적인 스캔 설계 기술을 제안한다. 본 논문에서 제안하는 시큐어 스캔 설계 기술은 IEEE 1149.1의 명령어 방식을 사용하여 거짓 키를 이용한 테스트를 진행한다. 또한 어플리케이션에 최적화 되어있는 암호화 IP 코아를 수정하지 않고 적용을 할 수 있다. SoC상의 IEEE 1149.1 제어기 표준을 유지하며 기존 방식에 비해 낮은 면적오버헤드 및 전력 소모량을 갖는 기술을 제안한다.

Improvement of Wuyiencin Biosynthesis in Streptomyces wuyiensis CK-15 by Identification of a Key Regulator, WysR

  • Liu, Yanyan;Ryu, Hojin;Ge, Beibei;Pan, Guohui;Sun, Lei;Park, Kyungseok;Zhang, Kecheng
    • Journal of Microbiology and Biotechnology
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    • 제24권12호
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    • pp.1644-1653
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    • 2014
  • Wuyiencin is produced by Streptomyces ahygroscopicus var. wuyiensis CK-15 and is widely used as an antifungal agent in agriculture. Analysis of wuyiencin biosynthetic gene clusters reveals wysR, a member of the LAL-family of transcriptional regulatory genes. WysR consists of an N-terminal PAS domain and a LuxR family C-terminal helix-turn-helix motif. However, the roles of wysR in wuyiencin biosynthesis are largely unknown. In this study, we showed that inactivation of wysR resulted in the complete loss of wuyiencin production, which could be restored by complementation with a single copy of wysR. Furthermore, we successfully increased wuyiencin production to a significantly higher level by overexpression of wysR in S. wuyiensis CK-15. Quantitative real-time RT-PCR analysis showed that WysR regulates wuyiencin biosynthesis by modulating other putative regulatory genes. Thus, WysR was identified as an activator of wuyiencin biosynthesis, and overexpression of wysR gene proved to be an effective strategy for improving wuyiencin production.

Protecting Multicast Sessions in WDM Networks with Sparse-Splitting Constraints

  • Wang, Xiong;Wang, Sheng;Li, Lemin
    • ETRI Journal
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    • 제29권4호
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    • pp.524-526
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    • 2007
  • In this letter, we study the multicast protection problem in sparse-splitting wavelength-division multiplexing (WDM) optical network, and propose a novel multicast protection algorithm called the shared source-leaf path-based protection (SLPP) algorithm. Unlike the proposals in previous studies, the backup paths derived by SLPP can share wavelength with the primary tree in sparse-splitting WDM networks. Simulations are used to evaluate the effectiveness of the SLPP algorithm.

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