• Journal of the Korean Mathematical Society
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• v.47 no.3
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• pp.483-494
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• 2010

Let R be a non-commutative prime ring and I a non-zero left ideal of R. Let U be the left Utumi quotient ring of R and C be the center of U and k, m, n, r fixed positive integers. If there exists a generalized derivation g of R such that $[g(x^m)x^n,\;x^r]_k\;=\;0$ for all x $\in$ I, then there exists a $\in$ U such that g(x) = xa for all x $\in$ R except when $R\;{\cong}\;=M_2$(GF(2)) and I[I, I] = 0.

• Speech Sciences
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• v.15 no.3
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• pp.31-38
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• 2008

The aim of this study was to find how English vowels affect the pronunciation of English sibilants /$d_3,\;{_3}$, z/ by Korean learners of English. Fifteen nonsense syllables composed by five vowels /a, e, i, o, u/ were pronounced six times by twelve Korean learners of English. Test scores were measured from the scoreboard made by a speech training software program, which was designed for English pronunciation practice and improvement. Results show that 1) the subjects had the lowest scores in /a_a/ position, and 2) subjects had lower scores in the /i_i/ position than in /e_e/, /o_o/ and /u_u/ positions when they pronounced $/d_3/,\;/{_3}/$, and /z/ in their respective inter-vocalic position. This study found that for the group studied Korean learners of English have more difficulty in pronouncing sibilants in /a_a/ and /i_i/ positions than in the other positions.

• Bulletin of the Korean Mathematical Society
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• v.20 no.1
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• pp.31-36
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• 1983

Let R be a commutative ring with 1, and A a unitary commutative R-algebra. By a derivation module of A, we mean a pair (M, d), where M is an A-module and d: A.rarw.M and R-derivation, i.e., d is an R-linear mapping such that d(ab)=a)db)+b(da). A derivation module homomorphism f:(M,d).rarw.(N, .delta.) is an A-homomorphism f:M.rarw.N such that f.d=.delta.. A derivation module of A, (U, d), there exists a unique derivation module homomorphism f:(U, d).rarw.(M,.delta.). In fact, a universal derivation module of A exists in the category of derivation modules of A, and is unique up to unique derivation module isomorphisms [2, pp. 101]. When (U,d) is a universal derivation module of R-algebra A, the A-module U is denoted by U(A/R). For out convenience, U(A/R) will also be called a universal derivation module of A, and d the R-derivation corresponding to U(A/R).

• Proceedings of the Korea Contents Association Conference
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• 2006.05a
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• pp.80-83
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• 2006

In this paper I intended to confirm the concept of u-City as the real space in which citizens live, not as the virtual city in cyber space, and also I try to suggest the way of considering about u-City on the scope of physical planning from the step of communication between human and computer to the step of intelligence of computer which service to the needs by its own decision for human being.

• Journal of the Korean Mathematical Society
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• v.56 no.3
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• pp.579-594
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• 2019

A colored space is a pair (X, r) of a set X and a function r whose domain is $\(^X_2\)$. Let (X, r) be a finite colored space and $Y,\;Z{\subseteq}X$. We shall write $Y{\simeq}_rZ$ if there exists a bijection $f:Y{\rightarrow}Z$ such that r(U) = r(f(U)) for each $U{\in}\({^Y_2}\)$ where $f(U)=\{f(u){\mid}u{\in}U\}$. We denote the numbers of equivalence classes with respect to ${\simeq}_r$ contained in $\(^X_i\)$ by $a_i(r)$. In this paper we prove that $a_2(r){\leq}a_3(r)$ when $5{\leq}{\mid}X{\mid}$, and show what happens when equality holds.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.6 no.3
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• pp.43-51
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• 1986

Triaxial compression tests were performed with control of vertical stress, confined pressure(${\sigma}_H$), and injection velocity by means of impervious soil samples with a different grain size, density and grout density. By measuring pore water pressure at the time of vertical fracturing around the bore-hole, relationships between main factors are described, and the factors are pore water pressure, confined pressure, vertical fracturing injection pressure(${\sigma}$) and the tension strength(${\sigma}_t$). The hydraulic fracturing of soft clay was occurred at the pressure which was less than the pressure obtained by the theory of elasticity. It was found that the above result was the influence of pore water pressure due to injection pressure($U_a$) and pore water pressure due to confined pressure($U_i$). Therefore, the vertical injection pressure at the time of fracturing needs to be changed as follows. $${\sigma}=2{\cdot}{{\sigma}_H}-(U_a+U_i)+{\sigma}_t$$.

• Journal of Fashion Business
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• v.13 no.5
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• pp.23-36
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• 2009

The purpose of this research is to design and to produce actual high value added wedding dress comprised of the pear blossoms pattern(梨花紋), which is one of the traditional patterns which was not researched to this day, and of the Dang-$\breve{u}$i(唐衣) image which reflects our concept of beauty as if as a means of conducting empirical study for the application of traditional Korean patterns to the contemporary application. pear blossoms effectively signifie the image of beautiful bride thanks to the pure, graceful and clean image of white flower, both in the external and internal aspects. The Dang-$\breve{u}$i of the Chosun Dynasty, which is another motif is one of the representative clothing that expresses the beauty of the curve when it comes to the Korean culture as traditional wedding dress. Attempt was made to develop design for wedding dress that expresses the Korean style beauty that combined the tradition and the modern. Towards this end, the project was composed of the Korean-like Ewha, image of the Dang-$\breve{u}$i I, II and III to design three dresses. The Dress I presents the image of pure, elegant and beautiful bride, while Dress II represents the pure and city like trendiness of the Korean women today as bride. Dress III was made centered on the image of elegant, and chaste bride. As for the materials used, hand-woven silk and silk organza used for the traditional clothes. As for the ornaments, embroidery, quilted work, beads, corsage, burn-out and other techniques were used for expression.

• The Journal of Dong Guk Oriental Medicine
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• v.7 no.1
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• pp.1-32
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• 1998

I found following idea, as a result of researching his Science idea, mainly, by translation of the "$Zh\bar{a}ng$ xi $ch\acute{u}n$ $Xu\acute{e}$ $Sh\acute{u}$ ssu $hsi\acute{a}ng$ "(張錫純 學術硏究). $Zh\bar{a}ng$ xi $ch\acute{u}n$ regarded $ch\tilde{u}ng$ $ch\bar{u}ng$ $ts'\bar{a}n$ $hs\bar{l}$' (衷中參西) as the core idea of The Chinese-Western medical combination. He didn't segregate philosophy of the West from One of the Orient. He persued to harmonize each other and thought that the Western medicint theory is included in the Chinese one in many parts. besides, He recognized that it is bad to reject each other, for the medical science's purpose is to save a life, and united The Chinese-Western medicine theory, by $ch\acute{u}ng$ $ch\tilde{u}ng$ $ch\bar{u}ng$ $ts'\bar{a}n$ $hs\bar{l}$'(衷中參西) idea which refers to consult the Western medicine on the basis of the Chinese one. Medical basic theory of $Zh\bar{a}ng$ xi $ch\acute{u}n$ brought up new views of the theory : Dae-gi(大氣), gi-Hwa(氣化) theory, Nongangubgan byung juing chi(論肝及肝病證治), Eum her chijung ja bi(陰虛治重滋脾). Lim Sangeung yong(臨床應用) of Hyul Her gub(血虛及)-Hwal Hyul Hwa $\breve{u}$ bub(活血化瘀法), on the basis of classics, such as, "$N\breve{e}i$ Ching"(內經), "Chin Kue $\breve{i}$ $y\bar{a}o$ $l\ddot{u}{\bar{e}}h$, "Shen $n\acute{u}ng$ $p\breve{e}n$ $t\acute{s}{\check{a}}o$ ching"(新農本草經) etc. I'll sum up $Zh\bar{a}ng$ xi $ch\acute{u}n's$ clinical idea now He unified Sang Han(像寒)-On Byung(溫病) with Yuk Kyung Byung Jung(六經辨證) and It was noticiable to utilize a kinds of Baek Ho Tang(白虎湯). He gave a detailed description about a method of grasp the symptoms of the cause of the internal medicine diseases and pathology and, he left abundant views of theory about using remedy and experience of clinic.

• Korean Journal of Mathematics
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• v.18 no.4
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• pp.335-342
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• 2010

Let D be an integral domain with quotient field K,$\mathcal{I}(D)$ be the set of nonzero ideals of D, and $w$ be the star-operation on D defined by $I_w=\{x{\in}K{\mid}xJ{\subseteq}I$ for some $J{\in}\mathcal{I}(D)$ such that J is finitely generated and $J^{-1}=D\}$. The D is called a Pr$\ddot{u}$fer $v$-multiplication domain if $(II^{-1})_w=D$ for all nonzero finitely generated ideals I of D. In this paper, we show that D is a Pr$\ddot{u}$fer $v$-multiplication domain if and only if $(A{\cap}(B+C))_w=((A{\cap}B)+(A{\cap}C))_w$ for all $A,B,C{\in}\mathcal{I}(D)$, if and only if $(A(B{\cap}C))_w=(AB{\cap}AC)_w$ for all $A,B,C{\in}\mathcal{I}(D)$, if and only if $((A+B)(A{\cap}B))_w=(AB)_w$ for all $A,B{\in}\mathcal{I}(D)$, if and only if $((A+B):C)_w=((A:C)+(B:C))_w$ for all $A,B,C{\in}\mathcal{I}(D)$ with C finitely generated, if and only if $((a:b)+(b:a))_w=D$ for all nonzero $a,b{\in}D$, if and only if $(A:(B{\cap}C))_w=((A:B)+(A:C))_w$ for all $A,B,C{\in}\mathcal{I}(D)$ with B, C finitely generated.

• Journal of applied mathematics & informatics
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• v.18 no.1_2
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• pp.497-503
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• 2005

This paper presents characterizations on the independence of the exponential and Pareto distributions by record values. Let ${X_{n},\;n {\ge1}$ be a sequence of independent and identically distributed(i.i.d) random variables with a continuous cumulative distribution function(cdf) F(x) and probability density function(pdf) f(x). $Let{\;}Y_{n} = max{X_1, X_2, \ldots, X_n}$ for n \ge 1. We say $X_{j}$ is an upper record value of ${X_{n},{\;}n\ge 1}, if Y_{j} > Y_{j-1}, j > 1$. The indices at which the upper record values occur are given by the record times {u(n)}, n \ge 1, where u(n) = $min{j|j > u(n-1), X_{j} > X_{u(n-1)}, n \ge 2}$ and u(l) = 1. Then F(x) = $1 - e^{-\frac{x}{a}}$, x > 0, ${\sigma} > 0$ if and only if $\frac {X_u(_n)}{X_u(_{n+1})} and X_u(_{n+1}), n \ge 1$, are independent. Also F(x) = $1 - x^{-\theta}, x > 1, {\theta} > 0$ if and only if $\frac {X_u(_{n+1})}{X_u(_n)}{\;}and{\;} X_{u(n)},{\;} n {\ge} 1$, are independent.