• Title/Summary/Keyword: Matsui

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DECOMPOSITION FORMULAE FOR GENERALIZED HYPERGEOMETRIC FUNCTIONS WITH THE GAUSS-KUMMER IDENTITY

  • Hayashi, Naoya;Matsui, Yutaka
    • Communications of the Korean Mathematical Society
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    • v.29 no.1
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    • pp.97-108
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    • 2014
  • In the theory of special functions, it is important to study some formulae describing hypergeometric functions with other hypergeometric functions. In this paper, we give some methods to obtain a lot of decomposition formulae for generalized hypergeometric functions.

CHARACTERIZATION THEOREMS OF RILEY TYPE FOR BICOMPLEX HOLOMORPHIC FUNCTIONS

  • Matsui, Yutaka;Sato, Yuhei
    • Communications of the Korean Mathematical Society
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    • v.35 no.3
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    • pp.825-841
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    • 2020
  • We characterize bicomplex holomorphic functions from several estimates. Originally, Riley [5] studied such problems in local case. In our study, we treat global estimates on various unbounded domains. In many cases, we can determine the explicit form of a function.

An Extension of Visual Cryptography and Its Application into Digital Watermark (시각암호의 확장과 디지털 워터마크에 응용)

  • 이혜주;박지환
    • Journal of Korea Multimedia Society
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    • v.1 no.1
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    • pp.80-89
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    • 1998
  • In this paper, we consider the method which a secret information is distributed in hard-copied image using visual cryptography that the secret can be identifying simply by human eyes. If slides constructed by patterning, which is one of dithering method, are considered from the viewpoint of visual cryptography, each slides will maintain the shape of original image because these slides have different Hamming weights. Therefore, this method has the advantage that information distributed into slides by stacking them can decode and the shape about the original image can be keeping as well. In this paper, we propose the method which shares the secret information into multiple original images by extension of ONM (Oka-Nakamura-Matsui) method which is devised to embed a secret information on hard-copied image. As a result, this proposed method is applicable to digital watermark because the copyright of image can be identified by stacking an image of owner for verification and the distributed multiple images.

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Multiple Linear Cryptanalysis-Revisited (블록 암호에 대한 효율적인 선형 공격 방법)

  • Choi, Jun;Hong, Deuk-Jo;Hong, Seok-Hee;Lee, Sang-Jin;Im, Jong-In
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.12 no.6
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    • pp.59-69
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    • 2002
  • Many Linear attacks have introduced after M. Matsui suggested Linear Cryptanalysis in 1993. The one of them is the method suggested by B. Kaliski and M. Robshaw. It was a new method using multiple linear approximations to attack for block ciphers. It requires less known plaintexts than that of Linear Cryptanalysis(LC) by Matsui, but it has a problem. In this paper, we will introduce the new method using multiple linear approximation that can solve the problem. Using the new method, the requirements of the known plaintexts is 5(1.25) times as small as the requirements in LC on 8(16) round DES with a success rate of 95%(86%) respectively. We can also adopt A Chosen Plaintext Linear Attack suggested by L. R. Knudsen and J. E. Mathiassen and then our attack requires about $2^{40.6}$ chosen plaintexts to recover 15 key bits with 86% success rate. We believe that the results in this paper contain the fastest attack on the DES full round reported so far in the open literature.