• 제목/요약/키워드: J-lattice

검색결과 271건 처리시간 0.032초

ALGEBRAIC MEET CONTINUOUS LATTICE

  • Lee, Seung On;Yon, Yong Ho
    • 충청수학회지
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    • 제20권4호
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    • pp.401-409
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    • 2007
  • This paper is sequel to [3]. In this paper, we discuss some properties of an algebraic meet-continuous lattice and study a complete lattice which can be embedded into an algebraic meet-continuous lattice.

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THE LATTICE DISTRIBUTIONS INDUCED BY THE SUM OF I.I.D. UNIFORM (0, 1) RANDOM VARIABLES

  • PARK, C.J.;CHUNG, H.Y.
    • 대한수학회지
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    • 제15권1호
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    • pp.59-61
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    • 1978
  • Let $X_1$, $X_2$, ${\cdots}$, $X_n$ be i.i.d. uniform (0,1) random variables. Let $f_n(x)$ denote the probability density function (p.d.f.) of $T_n={\sum}^n_{i=1}X_i$. Consider a set S(x ; ${\delta}$) of lattice points defined by S(x ; ${\delta}$) = $x{\mid}x={\delta}+j$, j=0, 1, ${\cdots}$, n-1, $0{\leq}{\delta}{\leq}1$} The lattice distribution induced by the p.d.f. of $T_n$ is defined as follow: (1) $f_n^{(\delta)}(x)=\{f_n(x)\;if\;x{\in}S(x;{\delta})\\0\;otherwise.$. In this paper we show that $f_n{^{(\delta)}}(x)$ is a probability function thus we obtain a family of lattice distributions {$f_n{^{(\delta)}}(x)$ : $0{\leq}{\delta}{\leq}1$}, that the mean and variance of the lattice distributions are independent of ${\delta}$.

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On Atomic Lattices

  • 이승온;연용호;황인재
    • 한국수학사학회지
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    • 제19권4호
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    • pp.97-106
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    • 2006
  • 격자의 기원은 수학에서 비롯된 것이 아니고 논리학에서 시작되었다([22]). 1880 년경 Peirce는 모든 격자는 분배 격자라고 생각하였으나 1890년경 $Schr{\"{o}}der$가 오류를 수정하였고, 1933년 Birkhoff가 lattice라는 단어를 처음 사용하였으나 이는 오늘의 격자와는 그 정의가 다르다. 이 논문에서는 Peirce를 소개하고 atomic 격자, atomistic 격자, J-격자, strong 격자 그리고 분배 격자의 상관관계를 연구한다.

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Degradation of thin carbon-backed lithium fluoride targets bombarded by 68 MeV 17O beams

  • Y.H. Kim;B. Davids;M. Williams;K.H. Hudson;S. Upadhyayula;M. Alcorta;P. Machule;N.E. Esker;C.J. Griffin;J. Williams;D. Yates;A. Lennarz;C. Angus;G. Hackman;D.G. Kim;J. Son;J. Park;K. Pak;Y.K. Kim
    • Nuclear Engineering and Technology
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    • 제55권3호
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    • pp.919-926
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    • 2023
  • To analyze the cause of the destruction of thin, carbon-backed lithium fluoride targets during a measurement of the fusion of 7Li and 17O, we estimate theoretically the lifetimes of carbon and LiF films due to sputtering, thermal evaporation, and lattice damage and compare them with the lifetime observed in the experiment. Sputtering yields and thermal evaporation rates in carbon and LiF films are too low to play significant roles in the destruction of the targets. We estimate the lifetime of the target due to lattice damage of the carbon backing and the LiF film using a previously reported model. In the experiment, elastically scattered target and beam ions were detected by surface silicon barrier (SSB) detectors so that the product of the beam flux and the target density could be monitored during the experiment. The areas of the targets exposed to different beam intensities and fluences were degraded and then perforated, forming holes with a diameter around the beam spot size. Overall, the target thickness tends to decrease linearly as a function of the beam fluence. However, the thickness also exhibits an increasing interval after SSB counts per beam ion decreases linearly, extending the target lifetime. The lifetime of thin LiF film as determined by lattice damage is calculated for the first time using a lattice damage model, and the calculated lifetime agrees well with the observed target lifetime during the experiment. In experiments using a thin LiF target to induce nuclear reactions, this study suggests methods to predict the lifetime of the LiF film and arrange the experimental plan for maximum efficiency.

A NOTE ON JANOWITZ'S HULLS OF GENERALIZED ORTHOMODULAR LATTICES

  • Park, Eun-Soon;Chung, Jin-Young
    • 대한수학회논문집
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    • 제15권3호
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    • pp.511-519
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    • 2000
  • If G is a strict generalized orthomodular lattice and H={I|I=[0, $\chi$, $\chi$$\in$G}, then H is prime ideal of the Janowitz's hull J(G) of G. If f is the janowitz's embedding, then the set of all commutatiors of f(G) equals the set of all commutators of the Janowitz's hull J(G) of G. Let L be an OML. Then L J(G) for a strict GOML G if and only if ther exists a proper nonprincipal prime ideal G in L.

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HD 기체에서의 수소 및 중수소 원자핵 스핀-격자 완화시간에 관한 핵자기공명 연구 (Proton and Deuteron Spin-Lattice Relaxation in Gaseous HD)

  • 유종훈
    • 한국자기학회지
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    • 제4권1호
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    • pp.52-55
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    • 1994
  • HD 기체에 대하 수소 및 중수소 원자핵 스핀-격자 완화시간 $T_{1}(H)$$T_{1}(D)$가 측정되었다. 실험데이타는 온도 30 K < T < 313 K 및 압력 0.67 atm < P < 1.92 atm에서 측정되어졌다. 핵자기공명 주파수는 각각 수소원자핵에 대해서 358.012 MHz였고 중수소원자핵에 대해서는 54.958 MHz였다. 측정된 $T_{1}(H)$$T_{1}(D)$의 비로부터 분자스핀 연산자들인 $J_{z}$${3J_z}^{2}-J(J+1)$에 관련된 상관시간의 비 ${\tau}_{1}/{\tau}_{2}$의 값이 얻어졌다. J = 1 상태에서의 원자핵 스핀-격자 완화시간이 온도의 함수로서 $T^{0.25}$에 비례하는 것이 관측되었다.

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A Note on a Family of Lattice Distributions

  • Stefen Hui;Park, C. J.
    • Journal of the Korean Statistical Society
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    • 제29권3호
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    • pp.315-318
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    • 2000
  • In this note we use the Poisson Summation Formula to generalize a result of Harris and Park (1994) on lattice distributions induced by uniform (0,1) random variables to those generated by random variables with step functions as their probability functions.

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격자형 광파이버필터의 최적설계에 관한 연구 (An Optimal Design Method for Optical Fiber Filter of Lattice Structure)

  • 이채욱;문병현;우홍채
    • 전자공학회논문지B
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    • 제30B권5호
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    • pp.34-42
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    • 1993
  • Due to the low loss, broadband and accurate short time delay properties of optical fiber, it has attracted as a delay medium for high speed and broad-band signal processing. In this paper, we consider the coherent optical fiber filter of lattice structure, which uses coherent light sources and consists of directional couplers and optical fiber delay elements.The differences between the optical fiber filter and the ordinary digital filter are 1) the coupling coefficients of directional couplers are restricted between 0 and 1. 2) the optical signal is divided into ${j\sqrt{a}}and\;{j\sqrt{1-a}}$ at the directional coupler. Considering these restrictions, the design formulae and condition of realibility for optical fiber filter of lattice structure which makes the optimal use of optical signal energy are derived.

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