• Title/Summary/Keyword: Huygens' fifth problem

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A Note on the History of the Gambler's Ruin Problem

  • Song, Seongjoo;Song, Jongwoo
    • Communications for Statistical Applications and Methods
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    • v.20 no.2
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    • pp.157-168
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    • 2013
  • This paper deals with the history of one of the well-known and historically important problems in probability, "Gambler's ruin". This problem was first solved by Pascal and Fermat and published by Huygens in 1657. It was studied and extended by many probabilists in early years and thus, it became an important problem in probability history, introducing many new concepts. We would like to introduce the problem in detail to readers and share the ideas on how new problems are developed, relating to old problems.

Superresolution of Optical Imaging System (광결상계의 초분해능)

  • 조영민;김종태;이상수
    • Korean Journal of Optics and Photonics
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    • v.5 no.3
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    • pp.349-355
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    • 1994
  • Superrsolution of an optical imaging system, which resolves $\epsilon_O$ (half width of the square top amplitude impulse function) less than the Rayleigh's resolution limit $\epsilon_R$, is theoretically treated by using the diffraction theory, and an experimental system is proposed. Initially superresolution is stated as an inverse problem, and an integral equation is derived as a function of parameter $\beta$, which is positive. The integration is numerically carried out for the given aperture and those given values of $\beta$, which is 1, 5, 10, 15, and 20. 1/2$\times$FWHM's of the amplitude impulse functions are meassured for the cases of diffrent value of {J and in the case of $\beta=5$, the half-width already approaches to $\epsilon_O=0.1$,urn, which is, in the case of the present work, one fifth of the Rayleigh's resolution limit. It is found both the pupil function and the phase of the Huygens wave are to be modified, and theories of the pupil function modulation plate and the phase modulation hologram plate are also presented. The result obtained may be useful in ultrafine optical lithography.graphy.

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