• Bulletin of the Korean Mathematical Society
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• v.51 no.2
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• pp.387-400
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• 2014

We prove that the set of k-type nonwandering points of a Z2-action T can be decomposed into a disjoint union of closed and T-invariant sets $B_1,{\ldots},B_l$ such that $T|B_i$ is topologically k-type transitive for each $i=1,2,{\ldots},l$, if T is expansive and has the shadowing property.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.2
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• pp.129-133
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• 1997

A total 943 accession of soybeans (G. max) and 50 wild soybeans (G. soja) were examined for leucine aminopeptidase (LAP) isozyme variation by 5％ polyacrylamide gel electrophoresis(PAGE) and isoelectric focusing(IEF) of pH 4~6.5. The Lap1*b by PAGE was the most common phenotype in both G. max and G. soja. The frequency of Lap1*b allele was observed to be higher in G. max(1.00) than in G. soja(0.96) of Korea. This result shows that G. max is fixed for Lapl*b allele at the Lap1 locus. LAP isozyme band type I and II were found using IEF of pH 4~6.5 in G. max and G. soja of Korea. Type I was observed from 92.8％ in G. max and 92.0％ in G. soja, and type II was discovered in 7.2％ G. max and 8.0％ G. soja. This result suggested the possibility to be found more various band types.

• Communications of the Korean Mathematical Society
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• v.33 no.4
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• pp.1097-1102
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• 2018

Let A and B be matrices which are polynomials in r pairwise commuting nilpotent matrices over a field. We give a sufficient condition for the null space of $A^i$ to equal that of $B^i$ for all i, in particular, for A and B to be similar.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.8
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• pp.1172-1179
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• 2022

This paper describes a design of point scalar multiplier for public-key cryptography based on binary Edwards curves (BEdC). For efficient implementation of point addition (PA) and point doubling (PD) on BEdC, projective coordinate was adopted for finite field arithmetic, and computational performance was improved because only one inversion was involved in point scalar multiplication (PSM). By applying optimizations to hardware design, the storage and arithmetic steps for finite field arithmetic in PA and PD were reduced by approximately 40%. We designed two types of point scalar multipliers for BEdC, Type-I uses one 257-b×257-b binary multiplier and Type-II uses eight 32-b×32-b binary multipliers. Type-II design uses 65% less LUTs compared to Type-I, but it was evaluated that it took about 3.5 times the PSM computation time when operating with 240 MHz. Therefore, the BEdC crypto core of Type-I is suitable for applications requiring high-performance, and Type-II structure is suitable for applications with limited resources.

• Korean Journal of Community Nutrition
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• v.9 no.1
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• pp.58-65
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• 2004

The purpose of this research was to examine the relationship between the plasma LDL particle size and blood lipid profile, dietary factors and anthropometric values (body mass index, waist circumference and waist/hip ratio). The subjects were 173 adults aged 23 to 81 years, selected from the Outpatient Clinic and Cardiovascular Department of the Seoul Municipal Hospital. Dietary data were obtained using a 3-day food record and analyzed using Korean and US nutrient databases. The subjects were divided into three groups by LDL particle size : type A (large buoyant LDL, > 25.5 nm, n=96), type I (Intermediate LDL,$25.2\leq-\leq25.5$ nm, n=18), and type B (small dense LDL, < 25.2 nm, n=59) groups. The type B group had higher age, waist circumference, and waist/hip ratio (WHR) than the type A and type I groups. Serum concentration of triglyceride, Apo B, LDL/HDL cholesterol ratio and atherogenic index were significantly higher in the type B group as compared to those in the other two groups. HDL cholesterol level and Apo A-I/Apo B ratio were significantly lower in the type B group than the other two groups. The plasma LDL particle size was highly correlated with triglyceride (r= -0.450), Apo B (r= -0.402) and HDL cholesterol (r= 0.418). However, there was no correlation between plasma LDL particle size and dietary intakes. This study showed that small dense LDL was an important biochemical risk factor that was associated with other risk factors.

• The Pure and Applied Mathematics
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• v.17 no.4
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• pp.333-340
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• 2010

We estimate the real rank of a composition series of closed ideals of a $C^*$-algebra such that its subquotients have continuous trace, which is equivalent to that the $C^*$-algebra is of type I.

• Korean Journal of Applied Biomechanics
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• v.16 no.2
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• pp.45-53
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• 2006

The purpose of this study was to analyze exercise related mechanical variables according to performance levels and Kumi-kata types in elite judo players (G1) and non-elite judo players, namely university players (G2). To achieve this purpose, three players in G1 whose main special skill was Morote-Seoinage and three university judo players(G2) was selected as comparative group. Then they were examined for distinguishing A and B types of Kumi-kata. Analyzed variables were the time required to show skills, knee degree, elbow degree. After analysing this study, conclusions were derived as follows. 1. In total necessary time of showing skills according to group of Kumi-kata type, G2 was longer than G1 in both A type (20.9%) and B type (23.7%). In necessary time of phase, in only 3P, G1 was shorter than G2 in A type (50%) and B type (75%). There was no difference in time required of 1P and 2P according to Kumi-kata type of group and in only 3P, B type was shorter than A type in both B type (75%) of G1 and B type (50%) of G2 2 There was no difference in elbow degree of offensive arm according to group of Kumi-kata type, however in A and B types, G1 could use skills by extending in kake phase, but G2 could use skills by bending. Elbow degree of offensive arm according to Kumi-kata type of group showed difference in E1. and F2 of G1. A and B types of G1 extended elbow degree in Kake phase, but G2 bent elbow degree so exercise program which could movable range extensively in Kake phase is needed.

• Bulletin of the Korean Mathematical Society
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• v.53 no.6
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• pp.1741-1751
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• 2016

We prove the boundary Harnack principle and the Carleson type estimate for ratios of solutions u/v of non-divergence second order elliptic equations $Lu=a_{ij}D_{ij}+b_iD_iu=0$ in a bounded domain ${\Omega}{\subset}R_n$. We assume that $b_i{\in}L^n({\Omega})$ and ${\Omega}$ is a $H{\ddot{o}}lder$ domain of order ${\alpha}{\in}$ (0, 1) satisfying a strong regularity condition.

• Journal of The Korean Astronomical Society
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• v.28 no.1
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• pp.31-43
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• 1995

We present UBVRI CCD photometry of the Type Ie supernova SN 19941 in M51 which was discovered on April 2, 1994 (UT). UBVRI CCD photometry of SN 1994 I were obtained for the period of the first two months from April 4, 1994, using the Seoul National University Observatory 60 cm telescope. The light curves of SN 19941 show several interesting features: (a) SN 19941 reaches the maximum brightness at B-band on April 8.23 (B = 13.68 mag), at V-band on April 9.10 (V = 12.89 mag), and at I-band on April 10.32 (I = 12.48 mag); (b) The light curves around the maximum brightness are much narrower than those of other types of supernovae; (c) The light curves after the peak decline more steeply than those of other types of supernovae; and (d) The colors get redder from $(V-R){\approx}0.2 mag ((V - I){\approx} 0.3 mag, (B - V){\approx}0.7 mag)$ on April 4 to $(V-R){\approx}0.6 mag ((V-1){\approx}0.9 mag, (B-V){\approx}1.3 mag)$ on April 18. Afterwards (V - R) colors get bluer slightly $(by\~0.005 mag/day)$, while (V-I) colors stay almost constant around $(V-1){\approx}1.0 mag$. The color at the maximum brightness is (B-V)=0.9 mag, which is $\~1$mag redder than the mean color of typical Type la supernovae at the maximum brightness. The light curves of SN 1994I are similar to those of the Type Ie supernova SN 1962L in NGC 1073. Adopting the distance modulus of $(m-M)_0 = 29.2 mag$ and the reddening of E(B - V) = 0.45 mag [Iwamoto et al. 1994, preprint for ApJ], we derive absolute magnitudes at the maximum brightness of SN 1994I, Mv(max) = -17.7 mag and MB(max) = -17.4 mag. This result shows that SN 1994I was $\~2$mag fainter at the maximum brightness compared with typical Type Ia supernovae. A narrower peak and faster decline after the maximum in the light curve of SN 1994I compared with other types of supernovae indicate that the progenitor of SN 1994I might be a lower mass star compared with those of other types of supernovae.

• Journal of the Korean Mathematical Society
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• v.47 no.6
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• pp.1147-1165
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• 2010

In this paper we compare a torsion free sheaf F on $P^N$ and the free vector bundle $\oplus^n_{i=1}O_{P^N}(b_i)$ having same rank and splitting type. We show that the first one has always "less" global sections, while it has a higher second Chern class. In both cases bounds for the difference are found in terms of the maximal free subsheaves of F. As a consequence we obtain a direct, easy and more general proof of the "Horrocks' splitting criterion", also holding for torsion free sheaves, and lower bounds for the Chern classes $c_i$(F(t)) of twists of F, only depending on some numerical invariants of F. Especially, we prove for rank n torsion free sheaves on $P^N$, whose splitting type has no gap (i.e., $b_i{\geq}b_{i+1}{\geq}b_i-1$ 1 for every i = 1,$\ldots$,n-1), the following formula for the discriminant: $$\Delta(F):=2_{nc_2}-(n-1)c^2_1\geq-\frac{1}{12}n^2(n^2-1)$$. Finally in the case of rank n reflexive sheaves we obtain polynomial upper bounds for the absolute value of the higher Chern classes $c_3$(F(t)),$\ldots$,$c_n$(F(t)) for the dimension of the cohomology modules $H^iF(t)$ and for the Castelnuovo-Mumford regularity of F; these polynomial bounds only depend only on $c_1(F)$, $c_2(F)$, the splitting type of F and t.