• Transactions of the Korean hydrogen and new energy society
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• v.7 no.2
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• pp.173-180
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• 1996

4-probe resistivity measurement technique was used to study kinetics of hydrogen absorption-desorption on Pd film($520{\AA}$ thick) at room temperature upto 1 bar. Kinetics data are fitted well to 1st order kinetics equation in ${\alpha}$ and ${\alpha}^{\prime}$ phases. In ${\alpha}+{\alpha}^{\prime}$ phase, absorption kinetics was very complicated, but it could be explained partially with nucleation and growth process. Ln(dR/dt) vs. time plot gives rate constant k value(R is resistance of sample, t is time). k value for absorption is $4^{-6}{\times}10^{-4}/sec$ in ${\alpha}$ phase. k is increasing upto $4^{\times}10^{-2}/sec$ as hydrogen pressure increasing in ${\alpha}^{\prime}$ phase. k is proportional to ln(Pop/Peq), where Peq is equilibrium plateau pressure and Pop is the opposing pressure. In contrast to bulk sample k value was decreasing with increasing number of A-D cycling in ${\alpha}^{\prime}$ phase absorption.

• Journal of applied mathematics & informatics
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• v.32 no.1_2
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• pp.17-26
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• 2014

In this paper, we present an algorithm for computing the number of points on the Jacobian varieties of genus 3 hyperelliptic curves of type $y^2=x^7+ax$ over finite prime fields. The problem of determining the group order of the Jacobian varieties of algebraic curves defined over finite fields is important not only arithmetic geometry but also curve-based cryptosystems in order to find a secure curve. Based on this, we provide the explicit formula of the characteristic polynomial of the Frobenius endomorphism of the Jacobian variety of hyperelliptic curve $y^2=x^7+ax$ over a finite field $\mathbb{F}_p$ with $p{\equiv}1$ modulo 12. Moreover, we also introduce some implementation results by using our algorithm.

• Proceedings of the Korean Information Science Society Conference
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• 2005.07b
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• pp.82-84
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• 2005

시맨틱 웹의 등장에 따라 RDF와 RDF Schema(RDF/RDFS)로 표현되는 웹 데이타의 양이 증가하고 있다. 이에 웹 데이타를 효율적으로 저장, 검색할 수 있는 인덱스 구조의 필요성이 높아지고 있다. 본 연구에서는 기존의 트리 모델을 위한 소수 레이블 기법(prime number labeling scheme)을 발전시켜, RDF/RDFS 인덱스 구조를 표현할 수 있는 그래프 모델을 위한 소수 레이블 기법을 제안한다. 제안한 기법은 기존의 소수 레이블 기법을 그래프에 적용하여 구조 질의(Structural Query)를 효율적으로 처리할 수 있고, 데이타 갱신 시에 인덱스를 재구성하지 않아도 되는 장점을 가지고 있다. 그리고 이전의 RDF/RDFS 인덱스 구조에서 효율적으로 처리하기 힘들었던 순환 방향성 그래프에 대한 질의도 쉴게 처리할 수 있다.

• Proceedings of the Korean Aquaculture Society Conference
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• 2004.05a
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• pp.321-322
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• 2004

Of the 20 arbitrarily chosen primers, six oligonucleotides decamer primers were used on the basis of the number of the polymorphisms generated in catfish (Silurus asotus) from Yesan and bullhead (Pseudobagrus fulvidraco) from Dangjin in Korea. Six primers were used generating a total of 602 scorable bands in catfish and 195 in bullhead population, respectively, ranging in size of DNA fragments from less than approximately 100 to larger than 2,000 base pairs (bp). Six primers yielded 199 polymorphic fragments (33.1 %) in catfish and 47 (24 %) in bullhead, respectively. In the present study, a total of 328 common fragments (an average of 54.7 per prime.) were observed in catfish population, whereas 84 (an average of 14.0 per prime.) in bullhead. The total number of specific fragments in catfish and bullhead population were 76and 64, respectively.

• The Pure and Applied Mathematics
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• v.23 no.3
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• pp.205-221
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• 2016

We formulate the additive entropy of a natural number in terms of the additive partition function, and show that its multiplicative entropy is directly related to the multiplicative partition function. We give a practical formula for the multiplicative entropy of natural numbers with two prime factors. We use this formula to analyze the comparative density of additive and multiplicative entropy, prove that this density converges to zero as the number tends to infinity, and empirically observe this asymptotic behavior.

• Journal of the Korean Mathematical Society
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• v.60 no.5
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• pp.1087-1107
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• 2023

Let E be an elliptic curve defined over ℚ of conductor N, c the Manin constant of E, and m the product of Tamagawa numbers of E at prime divisors of N. Let K be an imaginary quadratic field where all prime divisors of N split in K, P_K the Heegner point in E(K), and III(E/K) the Shafarevich-Tate group of E over K. Let 2u_K be the number of roots of unity contained in K. Gross and Zagier conjectured that if P_K has infinite order in E(K), then the integer c · m · u_K · |III(E/K)| $\frac{1}{2}$ is divisible by |E(ℚ)_tor|. In this paper, we prove that this conjecture is true if E(ℚ)_tor ≅ ℤ/2ℤ or ℤ/4ℤ except for two explicit families of curves. Further, we show these exceptions can be removed under Stein-Watkins conjecture.

• Bulletin of the Korean Mathematical Society
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• v.60 no.4
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• pp.863-872
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• 2023

Let n ⩾ 2 be an integer, we denote the smallest integer b such that gcd {(ⁿ_k) : b < k < n - b} > 1 as b(n). For any prime p, we denote the highest exponent α such that p^α | n as v_p(n). In this paper, we partially answer a question asked by Hong in 2016. For a composite number n and a prime number p with p | n, let n = a_mp^m + r, 0 ⩽ r < p^m, 0 < a_m < p. Then we have $$v_p\(\text{gcd}\{\(n\\k\)\;:\;b(n)1\}\)=\{\array{1,&&a_m=1\text{ and }r=b(n),\\0,&&\text{otherwise.}}$$

• Journal of the Korean earth science society
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• v.38 no.7
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• pp.511-521
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• 2017

This study analyzes Two-dimensional video disdrometer (2DVD) data while summer 2011-2012 in Daegu region and compares with Marshall and Palmer (MP) distribution to find out statistical characteristics and characteristics variability about drop size distribution (DSD) of Daegu region. As the characterize DSD of Daegu region, this study uses single moment parameters such as rainfall intensity (R), reflectivity factor (Z) and double moment parameters such as generalized characteristics number concentration ($N{_0}^{\prime}$) and generalized characteristics diameter ($D{_m}^{\prime}$). Also, this study makes an assumption that DSD function can be expressed as general gamma distribution. The results of analysis show that DSD of Daegu region has ${\log}_{10}N{_0}^{\prime}=2.37$, $D{_m}^{\prime}=1.04mm$, and c =2.37, ${\mu}=0.39$ on average. When the assumption of MP distribution is used, these figures then end up with the different characteristics; ${\log}_{10}N{_0}^{\prime}=2.27$, $D{_m}^{\prime}=0.9mm$, c =1, ${\mu}=1$ on average. The differences indicate liquid water content (LWC) of Daegu distribution is generally larger than MP distribution at equal Z. Second, DSD shape of Daegu distribution is concave upward. Other important facts are the characteristics of Daegu distribution change when Z changes. DSD shape of Daegu region changes concave downward (c =2.05~2.55, ${\mu}=0.33{\sim}0.77$) to cubic function-like shape (c =3.0, ${\mu}=-0.13{\sim}-0.33$) at Z > 45 dBZ. 35 dBZ ${\leq}$ Z > 45 dBZ group of Daegu distribution has characteristics similar to maritime cluster of diverse climate DSD study. However, Z > 45 dBZ group of Daegu distribution has a difference from the cluster.

• Journal of KIISE:Databases
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• v.35 no.5
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• pp.421-431
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• 2008

Recently XML is becoming a de facto standard for online data exchange between heterogeneous systems and also the research of streaming XML data filtering comes into the spotlight. Since streaming XML data filtering technique needs rapid matching of queries with XML data, it is required that the query processing should be efficiently performed. Until now, most of researches focused only on partial sharing of path expressions or efficient predicate processing and they were work for time and space efficiency. However, if containment relationship between queries is previously calculated and the lowest level query is matched with XML data, we can easily get a result that high level queries can match with the XML data without any other processing. That is, using this containment technique can be another optimal solution for streaming XML data filtering. In this paper, we suggest an efficient XML data filtering based on prime number indexing and containment relationship between queries. Through some experimental results, we present that our suggested method has a better performance than the existing method. All experiments have shown that our method has a more than two times better performance even though each experiment has its own distinct test purpose.

• Journal of the Korean Mathematical Society
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• v.39 no.5
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• pp.765-773
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• 2002

Let $textsc{k}$＝$F_{q}$(T) be a rational function field. Let $\ell$ be a prime number with ($\ell$, q-1) ＝ 1. Let K/$textsc{k}$ be an elmentary abelian $\ell$-extension which is contained in some cyclotomic function field. In this paper, we study the $\ell$-divisibility of ideal class number $h_{K}$ of K by using cyclotomic units.s.s.