• Proceedings of the Korean Vacuum Society Conference
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• 1996.06a
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• pp.68-68
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• 1996

• Bulletin of the Korean Mathematical Society
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• v.43 no.3
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• pp.619-626
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• 2006

Let m be any positive integer, R be a ring with identity, $M_m(R)$ be the matrix ring of all m by m matrices eve. R and $G_m(R)$ be the multiplicative group of all n by n nonsingular matrices in $M_m(R)$. In this pape., the following are investigated: (1) for any pairwise coprime ideals ${I_1,\;I_2,\;...,\;I_n}$ in a ring R, $M_m(R/(I_1{\cap}I_2{\cap}...{\cap}I_n))$ is isomorphic to $M_m(R/I_1){\times}M_m(R/I_2){\times}...{\times}M_m(R/I_n);$ and $G_m(R/I_1){\cap}I_2{\cap}...{\cap}I_n))$ is isomorphic to $G_m(R/I_1){\times}G_m(R/I_2){\times}...{\times}G_m(R/I_n);$ (2) In particular, if R is a finite ring with identity, then the order of $G_m(R)$ can be computed.

• Journal of Integrative Natural Science
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• v.8 no.4
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• pp.313-316
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• 2015

In this article, we compute the order of a general linear group $GL_n(A)$ over a finite ring A.

• Bulletin of the Korean Chemical Society
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• v.19 no.5
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• pp.569-575
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• 1998

Investigation of the structure of the gangliosides has proven to be very important in the understanding of their biological roles. We have determined the tertiary structure of asialoganglioside GM1 $(GA_1)$ using NMR spectroscopy and distance geometry calculations. All of the structures are very similar except the glycosidic torsion angles in the ring IV and ring III linkages. There are two low-energy structures for GA1, G1 and G2. G1 differs from G2 only in the IV-III glycosidic linkages and the orientation of acetamido group in ring III. There is a stable intramolecular hydrogen bond between the third hydroxyl group in ring I and the ring oxygen atom in ring II. Also, there may be a weak hydrogen bond between the second hydroxyl group in ring IV and the acetamido group in ring III. Small coupling constants of $^3J_{IH3,IOH3}\; and\; ^3J_{IVH2,IVOH2}$ support this result. Overall structural features of $(GA_1)$ are very similar to those of $(GM_1)$. It implicates that specificities of the sugar moieties in GM1 are caused not by their tertiary foldings, but mainly by the electrostatic interactions between the polar sialic acid and its receptors. Since it is evident that $(GA_1)$ is more hydrophobic than $(GA_1)$, a receptor with a hydrophobic binding site can recognize the $(GA_1)$ better than $(GA_1)$. Studies on the conformational properties of $(GA_1)$ may lead to a better understanding of the molecular basis of its functions.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.559-563
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• 1996

Total 215 magnet power supplies are under operation in Pohang Light Source(PLS). Current, voltage and peak power handling capabilities of DC power supply are in the range of 21 to 643V, 45 to 850A and 0.94 to 531KW, respectively. The DC power supplies can be categoriezed as uni-polar and bipolar power. Typical required stability and ripple of uni-polar power supplies are ${\pm}0.005%$ and ${\pm}0.05%$, respectively. The bipolar power supplies should be maintained within ${\pm}0.05%$ stability and ${\pm}0.5%$ ripple. Precise measurement results show that all power supplies meet or exceed the required specifications. The long term operation reliability to be sufficient for a stable operation of the Pohang Light Source.

• Korean Journal of Veterinary Research
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• v.44 no.1
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• pp.137-141
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• 2004

The purpose of this study was to compare easiness of application of polypropylene external total ring prosthesis (PPTRP, Group A) with that of polyvinylchloride external total ring prosthesis (PVCTRP, Group B), which were used for surgical correction of tracheal collapse in dogs. PPTRP was made from 3 ml syringe and PVCTRP from the drip chamber of intravenous administration set. Prostheses of group A (n=5) and B (n=5) were placed to cervical trachea in clinically normal 10 dogs, respectively weighing between 4 kg and 6 kg. There were mild coughing and swelling in one to three dogs of both groups for 3 days after surgery. No exercise intolerance was observed in both groups after surgery. There were no different results of clinical signs and radiographic views after surgery between group A and group B. The time (mean${\pm}$SD) to make total ring prosthesis, group A took $23.2{\pm}1.9$ minutes which was remarkably longer than that $(4.6{\pm}0.3)$ of group B. Also, the time to place around trachea, group A required $61.8{\pm}8.8$ minutes and group B $38.4{\pm}8.0$ minutes. Conclusionly, PVCTRP was timesaving and easier to make, fix, and suture than those of PPTRP. PVCTRP may be used alternatively to PPTRP for the tracheal collapse to treat in dogs.

• Communications of the Korean Mathematical Society
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• v.17 no.2
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• pp.221-227
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• 2002

In this paper we will show that the followings ; (1) Let R be a regular local ring of dimension n. Then $A_{n-2}$(R) = 0. (2) Let R be a regular local ring of dimension n and I be an ideal in R of height 3 such that R/I is a Gorenstein ring. Then [I] = 0 in $A_{n-3}$(R). (3) Let R = V[[ $X_1$, $X_2$, …, $X_{5}$ ]]/(p+ $X_1$$^{t1}$ + $X_2$$^{t2}$ + $X_3$$^{t3}$ + $X_4$$^2$+ $X_{5}$ $^2$/), where p $\neq$2, $t_1$, $t_2$, $t_3$ are arbitrary positive integers and V is a complete discrete valuation ring with (p) = mv. Assume that R/m is algebraically closed. Then all the Chow group for R is 0 except the last Chow group.group.oup.

• Communications of the Korean Mathematical Society
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• v.12 no.4
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• pp.855-864
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• 1997

Let K be a algebraically closed field of characteristic 0 and G a cyclic group of order n. We find the units and idempotent elements of the group ring KG by using the basic group table matrix of G.

• Bulletin of the Korean Chemical Society
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• v.10 no.4
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• pp.404-406
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• 1989

• Korean Journal of Mathematics
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• v.18 no.1
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• pp.97-103
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• 2010

It is well known that the group ring K[G] has the nontrivial Jacobson radical if K is a field of characteristic p and G is a finite group of which order is divided by a prime p. This paper is concerned with the structure of the Jacobson radical of such a group ring.