• Journal of the Korean Statistical Society
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• v.28 no.2
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• pp.235-251
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• 1999

In this paper we examine extremal behavior of a $textsc{k}$th-order stationary Markov chain {X\ulcorner} by considering excesses over a high level which typically appear in clusters. Excesses over a high level within a cluster define a cluster damage, i.e., a normalized sum of all excesses within a cluster, and all excesses define a damage point process. Under some distributional assumptions for {X\ulcorner}, we prove convergence in distribution of the cluster damage and obtain a representation for the limiting cluster damage distribution which is well suited for simulation. We also derive formulas for the mean and the variance of the limiting cluster damage distribution. These results guarantee a compound Poisson limit for the damage point process, provided that it is strongly mixing.

• Journal of The Korean Astronomical Society
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• v.15 no.2
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• pp.49-58
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• 1982

The UBVRIHKL magnitudes on Johnson system and space motions of M dwarf stars have been collected. This sample of M stars have been distinguished on a purely kinematical basis; the one with e<0.15, young disk population, with 0.150.3 halo population. On the color-color diagrams and the color excess-orbital eccentricity diagrams, there is no distinction between the old disk stars and the young disk stars. However (I-H) color could be used to distinguish halo stars from young and old disk stars and the color excesses, ${\Delta}(U-B),\;{\Delta}(B-V),\;{\Delta}(V-R),\;{\Delta}(H-K),\;{\Delta}(K-L),\;and\;{\Delta}(B-R)$ can be used as abundance indicators only for the halo stars. But these color excesses which are measures of blue excesses, are positive for the halo stars with smaller eccentricities and become negative for those with larger eccentricities.

• Journal of The Korean Astronomical Society
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• v.43 no.5
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• pp.153-159
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• 2010

Color excesses of classical Cepheids in the uvby color system are estimated for the calibration stars with distances from the literature that are measured independently. Intrinsic photometric indices for these stars are calculated and a calibrated empirical relation between (b - y)$_0$, period, [$c_1$], and [$m_1$] is derived through a linear fit. This relation is used to determine color excesses E(b-y) for 59 Cepheids. We also examine the period-color [log P : (b - y)$_0$] relation, and find no signs of nonlinearity. We estimate the effective temperature and surface gravity of several Cepheids using both Kurucz and MARCS/SSG grids for [Fe=H]=0.0. We confirm that both temperature and surface gravity are higher, by about 150K and 0.4 respectively, when the MARCS/SSG atmospheric grids are used.

• Clinical and Experimental Pediatrics
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• v.54 no.7
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• pp.282-286
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• 2011

Breastfeeding is the best source of nutrition for every infant, and exclusive breastfeeding for 6 months is usually optimal in the common clinical situation. However, inappropriate complementary feeding could lead to a nutrient-deficient status, such as iron deficiency anemia, vitamin D deficiency, and growth faltering. The recent epidemic outbreak of obesity in Korean children emphasizes the need for us to control children's daily sedentary life style and their intakes of high caloric foods in order to prevent obesity. Recent assessment of breastfeeding in Korea has shown that the rate is between 63% and 89%; thus, up-to-dated evidence-based nutritional management of breastfeeding infants to prevent common nutrient deficiencies or excesses should be taught to all clinicians and health care providers.

• Journal of The Korean Astronomical Society
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• v.16 no.2
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• pp.55-63
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• 1983

From UBVRI photometry and space motion data of 232 late type dwarf stars, it is found that for the stars of (R-I)<0.5, $\Delta$(U-B) and $\Delta$(B-V) color excesses are correlated with their orbital eccentricities. Therefore, $\Delta$(U-B) and $\Delta$(B-V) color excesses can be used as possible photometric abundance indicators for the stars of (R-I)<0.5. For the stars of (R-I)${\geq}$0.5, the correlation between color excess and orbital eccentricity is not clear. However, it is interesting to note that the high orbital eccentricity stars show some blue deficiencies and these blue deficiencies seem to be correlated with orbital eccentricity.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.72-79
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• 2016

The fungal morphologies and pellet sizes were controlled in acetophenone reduction by Rhizopus oryzae. The acetophenone conversion and (S)-phenylethanol enantiomeric excesses (e.e.) reached the peak after 72 h of incubation when using pellets with 0.54 mm diameter, which showed an excellent performance compared with suspended mycelia, clumps, and pellets with 0.65 or 0.75 mm diameter. Furthermore, nano-sized acetophenone was used as a substrate to improve the performances of biotransformation work. The results showed that the conversion of nanometric acetophenone and (S)-phenylethanol e.e. reached the maximum (both >99%) after 32 h of incubation when using 0.54 mm diameter pellets, at least 24 h in advance of the control group. On the other hand, Tween 80 and 1, 2-propylene glycol showed low or no toxicity to cells. In conclusion, pellets and acetophenone nanoemulsions synergistically result in superior performances of acetophenone reduction.

• Journal of The Korean Astronomical Society
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• v.38 no.2
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• pp.241-244
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• 2005

We have analysed near-infrared JHKL observations of the members of the $\approx$9 Myr-old $\eta$ Chamaeleontis cluster. Using (J - H)/(K - L) and (H - K)/(K - L) IR colour-colour diagrams for the brightest 15 members of the cluster, we find the fraction of stellar systems with near-IR excess emission was 0.60 $\pm$ 0.13 (2$\sigma$). For the CTT and WTT star population, we also find a strong correlation between the IR excess and Ha emission which is also known as an accretion indicator. The (K - L) excess of these stars appears to indicate a wide range of star-disk activity; from a CTT star with high levels of accretion, to CTT - WTT transitional objects with evidence for some on-going accretion, and WTT stars with weak or absent IR excesses. Among the brightest 15 members, four stars (RECX 5, 9, 11 and ECHA J0843.3-7905) with IR excesses ${\Delta}$(K - L) > 0.4 mag and strong or variable optical emission were identified as likely experiencing on-going mass accretion from their circumstellar disks which we confirmed their accretion disks from the optical high-resolution echelle spectroscopic study. The result-ing accretion fraction of 0.27 $\pm$ 0.13 (2$\sigma$) suggests that the accretion phase, in addition to the disks themselves, can endure for at least ${\~}$10 Myr.

• Journal of The Korean Astronomical Society
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• v.32 no.1
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• pp.41-53
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• 1999

We have carried out high-resolution observations along one-dimensional cuts through the three Galactic super-shells GS 064-01-97, GS 090-28-17, and GS 174+02-64 in the HI 21 cm and CO J=l-0 lines. By comparing the HI data with IRAS data, we have derived the distributions of the $I_{100}$ and $T_{100}$ excesses, which are, respectively, the 100 ${\mu}m$ intensity and 100 ${\mu}m$ optical depth in excess of what would be expected from HI emission. We have found that both the $I_{100}$ and $T_{100}$ excesses have good correlations with the CO integrated intensity W co in all three supershells. But the $I_{100}$ excess appears to underestimate $H_2$ column density N($H_2$) by factors of 1.5-3.8. This factor is the ratio of atomic to molecular infrared emissivities, and we show that it can be roughly determined from the HI and IRAS data. By comparing the $T_{100}$ excess with $W_{co}$, we derive the conversion factor X $\equiv$ N ($H_2$) /$W_{co}{\simeq}$ 0.26 - 0.66 in the three supershells. In GS 090- 28-17, which is a very diffuse shell, our result suggests that the region with N($H_2$) $\le$ $3 {\times} 10^{20} cm^{-2}$ does not have observable CO emission, which appears to be consistent with previous results indicating that diffuse molecular gas is not observable in CO. Our results show that the molecular gas has a 60/100 ${\mu}m$ color temperature $T_d$ lower than the atomic gas. The low value of $T_d$ might be due either to the low equilibrium temperature or to the lower abundance of small grains, or a combination of both.

• Tuberculosis and Respiratory Diseases
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• v.69 no.2
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• pp.108-114
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• 2010

Background: The aim was to estimate the differences between pulmonary disability grades according to the spirometry reference equations (the Korean equation and the Morris equation). Methods: Spirometry was performed on 16,916 male and 1,353 female special examination for pneumoconiosis, in the period of 2007~2009. Changes in predictive values for forced expiratory volume in one second ($FEV_1$), forced vital capacity (FVC) and $FEV_1$/FVC and in disability grade were evaluated using both equations. Results: Mean FVCs for men and women were 4,218.7 mL and 2,801.5 mL in predictive values after the application of the Korean equation, and 3,763.9 mL and 2,395.6 mL after the Morris equation, respectively. Compared with the Morris equation, the Korean equation showed 10.8% and 14.5% of excesses for men and women (p<0.001). Mean $FEV_1s$ for men and women were 3,102.5 mL and 2,107.1 mL in the Korean equation, and 2,667.8 mL and 1,699.6 mL in the Morris equation, respectively. Compared with the Morris equation, the Korean equation showed 14.0% and 19.3% of excesses for men and women (p<0.001). Men and women who showed the changes of disability grades using the Korean equation in place of the Morris equation were 23.9% (4,052/16,916) and 22.9% (311/1,353) on FVC, and 23.1% (3,913/16,916) and 10.7% (145/1,353) on $FEV_1$. Conclusion: Applying different reference equations for spirometry has resulted in changes for disability grades in special examination for pneumoconiosis.

• Journal of Microbiology and Biotechnology
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• v.7 no.5
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• pp.329-332
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• 1997

Cell-free extracts of Streptomyces neyagawaensis SL-387 grown on a chemically defined medium supplemented with DL-3-amino-3-phenylpropionic acid (APP) produced N-acetyl-APP (Ac-APP) in the presence of APP and acetyl coenzyme A. The APP obtained by acid hydrolysis of the Ac-APP was D-configuration: $[\alpha]_D+6.5^{\circ}(H_2O)\;at\;20^{\circ}C$, optical purity 92% enantiomeric excesses (ee). These results suggest that an N-acetyltransferase exists in the cell-free extract as a novel enzyme with specificity for D-APP.