• Journal of the Chungcheong Mathematical Society
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• v.31 no.4
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• pp.387-396
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• 2018

Topology may described a pattern of existence of elements of a given set X. The family ${\tau}(X)$ of all topologies given on a set X form a complete lattice. We will give some topologies on this lattice ${\tau}(X)$ using a fixed topology on X and we will regard ${\tau}(X)$ a topological space. Our purpose of this study is to comparison new topologies on the family ${\tau}(X)$ of all topologies induced old one.

• Journal of applied mathematics & informatics
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• v.23 no.1_2
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• pp.25-42
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• 2007

A direct solver for the Legendre tau approximation for the two-dimensional Poisson problem is proposed. Using the factorization of symmetric eigenvalue problem, the algorithm overcomes the weak points of the Schur decomposition and the conventional diagonalization techniques for the Legendre tau approximation. The convergence of the method is proved and numerical results are presented.

• Communications of the Korean Mathematical Society
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• v.26 no.2
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• pp.291-296
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• 2011

Cs$\'{a}$sz$\'{a}$r [3] introduced the notions of ${\gamma}$-compact and ${\gamma}$-operation on a topological space. In this paper, we introduce the notions of almost ${\Gamma}$-compact, (${\gamma},{\tau}$)-continuous function and (${\gamma},{\tau}$)-open function defined by ${\gamma}$-operation on a topological space and investigate some properties for such notions.

• Journal of the Chungcheong Mathematical Society
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• v.24 no.4
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• pp.919-920
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• 2011

For two even unimodular positive definite integral quadratic forms A[X], B[X] in n-variables, J. K. Koo [1, Theorem 1] showed that ${\theta}_A(\tau)/{\theta}_B(\tau)$ is a rational function of J, satisfying a certain condition. Where ${\theta}_A(\tau)$ and ${\theta}_B(\tau)$ are theta series related to A[X] and B[X], respectively, and J is the classical modular invariant. In this paper we give a simple proof of Theorem 1 of [1].

• Polymer(Korea)
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• v.27 no.3
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• pp.255-264
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• 2003

Various chain sizes 3-arm star polystyrenes (PS, $M_{w}$=2.80$\times$10$^{5}$ , 2.49$\times$10$^{6}$ g/mol) in t-decalin solution were measured at the temperature range of 20~7$0^{\circ}C$ by means of viscometry and laser light scattering. In order to show universality in the expansion factor of 3-arm star polymer, it was expected that (N/ $R_{G,Br,o}$$^{2}$)$^{3}$2/$\tau$/$\tau$$_{C}$ would be used as an universal parameter, where $R_{G,Br,o}$ was the unperturbed radius of gyration of star PS. However, much better universality had been observed when (N/ $R_{G,Br,o}$$^{2}$)$^{3}$2/$\tau$/$\tau$$_{C}$ parameter of the linear PS was used even for the 3-arm star PS. It could be explained if branching effect had been already taken into account in the part of $\tau$/$\tau$$_{C}$(=[(Τ-Θ$_{Tc}$ )/Θ$_{Tc}$ ]/[(Θ$_{Tc}$ -Τ$_{c}$)/ $T_{c}$]). Here N and Θ$_{Tc}$ stand for the number of monomer unit in a single polymer chain and a kind of theta temperature as the critical solution temperature $T_{c}$ of the infinite molecular weight, respectively.ely.y.ely.

• Korean Journal of Optics and Photonics
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• v.7 no.4
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• pp.341-347
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• 1996

The photocount distribution from a quasi-thermal light source, a moving ground glass disk (surface roughness; 9 ${\mu}{\textrm}{m}$) illuminated by a well-stabilized He-Ne laser, is measured by a photon counting system, and analyzed with theoretical calculations. The distribution approaches the Poisson distribution for the long coherence time ${\tau}_c$ compared to the measuring time T. The coherence time ${\tau}_c$ of the quasi-thermal source can be changed by controlling the velocity v of the motor driving the glass disk. By the comparison of experimental results and theory for the condition of T/ ${\tau}_c$ >>1, the coherence time ${\tau}_c$ of the quasi-thermal source is turned out to be in the range of 31.43 $mutextrm{s}$~2.48 $mutextrm{s}$ according to the circumferential velocity of the disk, and compared with the simple calculation of $\sigma$/v.

• Archives of Pharmacal Research
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• v.26 no.4
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• pp.264-269
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• 2003

5-Aminosalicylic acid (5-ASA) is an active ingredient of therapeutic agents used for Crohn s disease and ulcerative colitis. Because it is absorbed rapidly and extensively in the upper intestine, delivery of the agent specifically to the colon is necessary. We selected taurine as a colon-specific promoiety and designed 5-aminosalicyltaurine (5-ASA-Tau) as a new colon-specific prodrug of 5-aminosalicylic acid (5-ASA). It was expected that introduction of taurine would restrict the absorption of the prodrug and show additive effect to the anti-inflammatory action of 5-ASA after hydrolysis. 5-ASA-Tau was prepared in good yield by a simple synthetic route. The apparent partition coefficient of 5-ASA-Tau in 1-octanol/pH 6.8 phosphate buffer or $CHCl_3$/pH 6.8 phosphate buffer was 0.10 or 0.18, respectively, at $37^{\circ}C$. To determine the chemical and biochemical stability in the upper intestinal environment, 5-ASA-Tau was incubated in pH 1.2 and 6.8 buffer solutions, and with the homogenates of tissue and contents of stomach or small intestine of rats at $37^{\circ}C$. 5-ASA was not detected from any of the incubation medium with no change in the concentration of 5-ASA-Tau. On incubation of 5-ASA-Tau with the cecal and colonic contents of rats, the fraction of the dose released as 5-ASA was 45% and 20%, respectively, in 8 h. Considering low partition coefficient and stability in the upper intestine, 5-ASA-Tau might be nonabsorbable and stable in the upper intestine. After oral administration, it would be delivered to the colon in intact form and release 5-ASA and taurine. These results suggested 5-ASA-Tau as a promising colon-specific prodrug of 5-ASA.

• Kyungpook Mathematical Journal
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• v.45 no.2
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• pp.249-254
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• 2005

Let N be a prime left near-ring with multiplicative center Z and f be a generalized $({\sigma},{\tau})-derivation$ associated with d. We prove commutativity theorems in prime near- rings with generalized $({\sigma},{\tau})-derivation$.

• Communications of the Korean Mathematical Society
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• v.10 no.4
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• pp.839-847
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• 1995

For the given torsion theory $\tau$, we study some equivalent conditions when the localized ring $R_\tau$ be semisimple artinian (Theorem 4). Using this, if $R_\tau$ is semisimple artinian ring, we study when does the given ring R become left V-ring?

• East Asian mathematical journal
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• v.24 no.4
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• pp.389-398
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• 2008

In this paper, some results of [6] concerning orthogonal ($\sigma$, $\tau$)-derivations and generalized ($\sigma$, $\tau$)-derivations are generalized for a nonzero ideal of a semiprime ring.