• 정보보호학회지
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• 제4권2호
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• pp.18-22
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• 1994

함수 f(x) : GF$(2)^n $\longrightarrow$ GF$(2)^n 은 부울함수인 n개의 좌표함수를 사용하여 f= $(f_1,f_2,...f_n)과 같이 표현 될 수 있다. 이때, 함수 f(x)의 암호론적 안전성은 f(x)의 좌표함수들의 안전성과 깊은 관계가 있다. 이제 주어진 함수의 비선형성을 부울함수들의 비선형성을 통해 살펴보고, 또한 비선형함수와 해쉬함수와의 관계에 대해 살펴본다.

• 충청수학회지
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• 제34권3호
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• pp.209-219
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• 2021

A set {a₁, a₂, ⋯ , a_m} of positive integers is called a Diophantine m-tuple if a_ia_j + 1 is a perfect square for all 1 ≤ i < j ≤ m. Let F_n be the nth Fibonacci number which is defined by F₀ = 0, F₁ = 1 and F_n+2 = F_n+1 + F_n. In this paper, we find the extendibility of Diophantine pairs {F_2k, b} with some conditions.

• 한국해양공학회지
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• 제13권4호통권35호
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• pp.55-62
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• 1999

Cold rolled steel has much plastic strain in the material surface produced by manufacturing process. The strain causes the variation of surface residual stress, in which influences the fatigue behavior under repeated loading. As experimental results, it was confirmed that the behavior of residual stress ${\sigma}_r$, with cycle N consisted of three stages except stress amplitude near fatigue limit in SPCC steel. On the first stage compressive residual stress decreased rapidly, on the second stage gradually, and on the last stage slightly. The relation between ${\sigma}_r$, and log N appeared linear behavior except the early part of cycle ratio $N/N_f$. The average gradient of ${\sigma}_r$, with respect to log N seemed to take a constant value without initial cycle ratio. On the other hand, the $N_f$ line was regressed by the first-order polynomial equation on ${\sigma}_r-log\;N_f$ diagram. Therefore, this study showed that both the gradient of ${\sigma}_r$, with respect to log N and the $N_f$ line was useful in predicting the cycle ratio $N/N_f$.

• 한국정보처리학회논문지
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• 제1권2호
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• pp.184-193
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• 1994

본 논문은 최소목(Minimum-weight Spanning Tree, MST)에 있어서 네트워크의 랭크 중 몇개가 삭제(또는 파괴) 또는 추가(또는 회복) 되었을 때, MST를 재구성하는 분산 알고리즘을 제안한다. 본 논문에서 제안한 알고리즘의 메세지 복잡도는 Ο(m＋n log(t＋f))이고, 이상시간 복잡도는 Ο(n＋n log(t＋f))가 되며, 여기서 n은 네트워크의 프로세서의 수이고 t(resp. f)는 추가되는 링크의 수(resp. 이전 MST의 삭제된 링크의 수)이다. 그래서 네트워크의 형태가 변형이 된 다음에 f=O이고 m=e일 경우에는 m=t＋n이 된다. 또한 본 논문의 마지막 부분에서는 링크의추가, 삭제와 마찬가지로 프로세서의 추가, 삭제되었을 경우의 알고리즘도 제안한다.

• Korean Journal of Mathematics
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• 제29권4호
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• pp.733-740
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• 2021

Let (F_n)_n≥0 be the Fibonacci sequence and p be a prime number. For 1≤k≤m, the Fibonomial coefficient is defined as $$\[\array{m\\k}\]_F=\frac{F_{m-k+1}{\ldots}{F_{m-1}F_m}}{{F_1}{\ldots}{F_k}}$$ and $\[\array{m\\k}\]_F=0$ whan k>m. Let a and n be positive integers. In this paper, we find the conditions of prime number p which divides Fibonomial coefficient $\[\array{P^{a+n}\\{p^a}}\]_F$. Furthermore, we also find the conditions of p when $\[\array{P^{a+n}\\{p^a}}\]_F$ is not divisible by p.

• Kyungpook Mathematical Journal
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• 제55권3호
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• pp.641-652
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• 2015

In this paper we study the problem of normal families of meromorphic functions concerning shared values. Let F be a family of meromorphic functions in the plane domain $D{\subseteq}{\mathbb{C}}$ and n, k be two positive integers such that $n{\geq}k+1$, and let a, b be two finite complex constants such that $a{\neq}0$. Suppose that (1) $f+a(f^{(k)})^n$ and $g+a(g^{(k)})^n$ share b in D for every pair of functions f, $g{\in}F$; (2) All zeros of f have multiplicity at least k + 2 and all poles of f have multiplicity at least 2 for each $f{\in}F$ in D; (3) Zeros of $f^{(k)}(z)$ are not the b points of f(z) for each $f{\in}F$ in D. Then F is normal in D. And some examples are provided to show the result is sharp.

• Journal of the Korean Statistical Society
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• 제18권1호
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• pp.62-71
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• 1989

We consider a Markov proces ${X_n} on [0,\infty)^k$ which is generated by $X_{n+1} = f(X_n) + \varepsilon_{n+1}$ where f is a continuous, nondecreasing concave function. Sufficient conditions for the existence of a unique invariant probability measure for ${X_n}$ are obtained.

• 열처리공학회지
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• 제3권1호
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• pp.1-7
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• 1990

To investigate the influence of r.f. power and electrode distance on the TiN deposition, TiN films were deposited onto STC3, STD11 steel and Si-wafer from gas mixtures of $TiC_4/N_2/H_2$ using the radio frequency plasma assisted chemical vapor deposition. The crystallinity of TiN film could be improved by the increase of r.f. power and the decrease of electrode distance. The TiN coated layer contains chlorine, its content were decreased with increasing r.f. power as well as decreasing electrode distance. And the thickness of deposited TiN was largely affected by r.f. power and electrode distance. The hardness of deposited TiN reached a maximum value of about Hv 2,000.

• 한국세라믹학회지
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• 제28권8호
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• pp.647-653
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• 1991

In order to synthesize fine AlN powder by the direct nitridation of Aluminum metal power added LiF and BaF2 as additives was heated at 150$0^{\circ}C$ for 3 hrs. in nitrogen gas with flow rate of 20 mι/sec. Additives are promoted the nitridation by prevented the aggromerate of powders when 3% LiF and 2% BaF2 were added to Al metal powder. Rate of nitridation was about 100% and average size of AlN powders were very fine such as 0.3 ${\mu}{\textrm}{m}$. Specific surface area of synthesized AlN powder was 3.95$m^2$/g and also O2 and N2 contents were 2.595% and 33.25%, respectively.

• Archives of Pharmacal Research
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• 제15권2호
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• pp.138-141
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• 1992

The new N-aryl-benz[f]-indole-4, 9-dione derivatives were synthesized via in tramolecular cyclization when triethylamine was employed as a base for the reaction of 2-chloro-3-$(\alpha$-cyano-$\alpha$-ethoxycarbonyl-methyl)-1, 4-naphthoquinone and arylamines.