• Title/Summary/Keyword: logarithm

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Effects of Water on the Electrical Conductivity of Magnesium Metaphosphate Glasses (MgO.$P_2O_5$ 유리의 전기전도도에 미치는 수분의 영향)

  • 강은태;박용완
    • Journal of the Korean Ceramic Society
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    • v.23 no.4
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    • pp.85-89
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    • 1986
  • Electrical conductivity have been measured as function of temperature in MgO.$P_2O_5$ glasses containing small amounts of water. Conduction was due to the contribution of $H^+$ and the mobility of protons in the glass increased linearly with increasing its concentration. The conductivity was pro-portional to the square of the proton concentration and the activation energy decreased linerly with increasing logarithm of the proton concentration, And $$\sigma$_0$ and $A_0$ was independent of the proton concentration but not on glass compositions.

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A "Paradoxical" ID-Based Key Distribution Protocol for Mobile Communication Systems (이동통신 시스템을 위한 "역설적인" ID-Based 키분배 방식)

  • 최연이;김성덕;양형규;원동호
    • Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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    • 1995.11a
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    • pp.307-313
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    • 1995
  • 본 논문에서는 기존에 제안된 이동통신용 키분배 방식의 문제점을 분석하고, Girault가 제안한 자체인증 공개키(Self-certified public keys) 개념을 이용한, 인증자에 기반을 둔(Certification-based) 방식이 아닌 개인식별정보에 기반을 둔(Identity-based) 방식이면서도 사용자가 자신의 비밀키를 선택할수 있는, 이동 퉁신망에 적용가능한 "역설적인" ID-based 키분배 방식을 제안한다. 제안한 방식의 안전성은 고차 잉여류 문제(${\gamma}$$^{th}$ -residuosity problem)와 이산대수(discrete logarithm) 문제에 근거한다. 문제에 근거한다.

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An applicable Key Distribution and Authentication Protocol in Personal Communication Networks (개인 통신망에서 적용가능한 인증 및 키분배 프로토콜)

  • 송희삼;전문석
    • Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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    • 1995.11a
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    • pp.331-337
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    • 1995
  • In this paper, We present that protocols have already proposed an applicable key distribution and authentication protocol based discrete logarithm and prime-factorization problem in PCN(Personal Communication Network) is anaysised. We newly propose identiity-based protocol using smart card. This proposed potocol is that Fiat-Shamir identification scheme and a new key distribution scheme based on Fiat-Shamir identification scheme are joined. Proposed protocol is compared with suiting protocols with respect to security and efficiency to evalate performance, so its calculation is reduced in key distribution and authentication to evaluate performance.

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Studies on Interaction of Essential Metal Ions with Bioactive Ligands

  • Tewari, Brij Bhushan
    • Bulletin of the Korean Chemical Society
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    • v.25 no.6
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    • pp.809-812
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    • 2004
  • Complexation reactions of nitrilotriacetate (NTA) and penicillamine with $Cu^{2+}$ and $Co^{2+}$ have been studied in solution phase using paper electrophoresis technique. The stability constants of the complexes Cu(II)-nitrilotriacetate-penicillamine and Co(II)-nitrilotriacetate-penicillamine have been found to be $6.64{\pm}0.03\;and\;5.86{\pm}0.05$ (logarithm stability constant values), respectively at 35$^{\circ}C$ and ionic strength 0.1 M.

Parallel Algorithms for the Discrete Logarithm Problem dn SIMD Machines (SIMD상에서 이산대수 문제에 대한 병렬 알고리즘)

  • 김양희;정창성
    • Review of KIISC
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    • v.4 no.2
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    • pp.40-46
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    • 1994
  • 고속 계산을 요구하는 분야에서는 여러개의 프로세싱 소자를 사용하여 속도를 증가시키는 병렬 처리의 필요성이 점점 증대되고 있다. 특히 암호처리에서 이산대수 문제나 factorization문제는 많은 시간이 걸리므로 고속계산을 위한 병렬처리가 매우 중요하다. 본 논문에서는 Pohlig-Hellman에 의한 이산대수 알고리즘을 SIMD구조의 병렬 컴퓨터상에서 고속으로 처리할 수 있는 두가지 병렬 이산대수 알고리즘을 제시하며, 이를16개의 트랜스퓨터로 구성된 병렬 컴퓨터인 KOPS(Korea Parallel System)상에서 구현한 성능평가를 제시한다.

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Verifiable Self-Certified Identification and Key-Distribution Protocols (검증 가능한 자체인증 개인식별 및 키분배 프로토콜)

  • Kim, Gyeong-Guk;Yu, Jun-Seok;Won, Dong-Ho
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.10
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    • pp.2722-2727
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    • 1999
  • In this paper we propose verifiable self-certified identification and key distribution protocols which has advantages of certificate-based scheme and Girault's self-certified public key. The security of the proposed protocols is based on ${\gamma}$\ulcorner-residuosity problem and discrete logarithm problem.

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Semiparametric accelerated failure time model for the analysis of right censored data

  • Jin, Zhezhen
    • Communications for Statistical Applications and Methods
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    • v.23 no.6
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    • pp.467-478
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    • 2016
  • The accelerated failure time model or accelerated life model relates the logarithm of the failure time linearly to the covariates. The parameters in the model provides a direct interpretation. In this paper, we review some newly developed practically useful estimation and inference methods for the model in the analysis of right censored data.

A "Paradoxical" identity-based scheme based on $\gamma^{th}$-residuosity problem and discrete logarithm problem (고차잉여류 문제와 이산대수 문제에 기반을 둔 역석적인 id-based암호 시스템)

  • 박성준
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.4 no.2
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    • pp.90-118
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    • 1994
  • 본 논문에서는 certificatoin-based 방식이 아닌 id-based방식이면서도 사용자가 자신의 비밀키를 선택할 수 있는 역설적인 id-based 방식을 제안한다. 제안한 방식은 Girault가 제안한 self-certified공개키 개념을 id-based방식에 적용한 것이다. 제안한 방식의 안전성은 고차잉여류 문제와 이산대수 문네에 기반을 두고 있다.

On the Discrete Logarithm of an Elliptic Curve (새로운 타원곡선 이산로그 공격)

  • 천정희
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.8 no.3
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    • pp.95-104
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    • 1998
  • 타원곡선 이산로그는 특별한 경우에는 다항식 시간 혹은 준지수 시간안에 푸는방법이 알려져 있으나, 일반적인 경우에는 지수 시간이 걸려야 풀 수 있는 문제로 알려져 있다. 본 고에서는 타원곡선 이산로그를 푸는 새로운 방법을 제시한다. 본 방법에 의하면 유한체 위에서 정의된 타원곡선을 rank가 3이하인 유리수위의 타원곡선으로 lifting할 수 있으면 다항식 시간안에타원곡선 이산로그 문제를 풀 수 있다.

THE STUDY ON GENERALIZED (p, q)-POLY-GENOCCHI POLYNOMIALS WITH VARIABLE a

  • H.Y. LEE
    • Journal of Applied and Pure Mathematics
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    • v.5 no.3_4
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    • pp.197-209
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    • 2023
  • In this paper, the generalized (p, q)-poly-Genocchi polynomials with variable a is defined by generalizing it more, and various properties of this polynomial are introduced. To do this, we define a generating function and use the definition to introduce some interesting properties as follows: basic properties, relation between Stirling numbers of the second kind and generalized (p, q)-poly-Genocchi polynomials with variable a and symmetric properties.