• Bulletin of the Korean Chemical Society
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• v.31 no.4
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• pp.869-873
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• 2010

A series of novel chiral tert-amino alcohols 4a-h derived from enantiomerically pure phenylalanine were synthesized efficiently and used as chiral ligands in the catalytic enantioselective ethylation of aldehydes with diethylzinc (diethylzinc-to-aldehyde addition). The use of 10 mol % of the amino alcohols led to the corresponding sec-alcohols with excellent enantioselectivities (up to 100% ee) and high yields.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1537-1540
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• 2013

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.472-473
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• 2006

Maghemite and hematite nanospheres were synthesized by using the Sol-gel technique. The structural properties of these nanosphere powders were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), and pore size distribution. Hematite phase shows crystalline structures. The mean particle size that resulted from BET and XRD analyses were 4.9 nm and 2 nm. It can be seen from transmission electron microscopy that the size of the particles are very small which is in good agreement with the FESEM and the X-ray diffraction. The BET and pore size method were employed for specific surface area determination.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.676-677
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• 2006

Synthesis of zinc oxide nanorods, sheets and flower like structure were done by the sol-gel method using zinc acetate dihydrate and sodium hydroxide at $80^{\circ}C$ with 12 hours refluxing time nanorods, in case of as synthesized powder, with diameter of 20-60nm. Annealing at higher temperature (300 and $500^{\circ}C$,) in air ambient changes the morphology to sheet and flower like structure. The standard peak of zinc oxide was observed in IR at $523cm^{-1}$. The UV-VIS spectroscopy of zinc oxide shows a characteristic peak at 375nm.

• Korean Journal of Clinical Laboratory Science
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• v.45 no.1
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• pp.9-15
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• 2013

Hepatitis B virus (HBV) infection has recently shown to be associated with diabetes mellitus. The objective of this study was to investigate the relationship between chronic hepatitis B and diabetes mellitus indicators. We evaluated anthropometry, metabolic syndrome risk factors, fasting glucose, HbA1c, and C-peptide among the normal and HBV subjects. The partial correlation and average comparison analysis were used to assess the independent association between chronic hepatitis B and diabetes mellitus indicators. Average comparisons of normal and HBV subjects were significantly different in fasting glucose (p<0.000), HbA1c (p<0.000), C-peptide (p<0.000), alanine transaminase (ALT) (p<0.000) and aspartate transaminase (AST) (p<0.000). We may suggest that HBV infection is related to diabetes mellitus indicators such as fasting glucose, HbA1c and C-peptide.

• Korean Journal of Clinical Laboratory Science
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• v.44 no.2
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• pp.39-45
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• 2012

The purpose of this study was to determine the association between serum uric acid, abdominal obesity, and waist circumference (WC) in Korean. A total of 208 healthy examinees were examined at Gimcheon Medical Center from July 2011 to December 2011. WC and body mass index (BMI) of subjects were measured as well as blood pressure, fasting blood sugar level, High Density Lipoprotein (HDL) and Low Density Lipoprotein (LDL) cholesterol, C-reactive protein (CRP), triglycerides, and serum uric acid (SUA). In both men (p<0.05) and women (p<0.01), BMI and SUA were significantly correlated with WC. In men, triglycerides (r=0.501, p<0.01) had a positive correlation with WC, and CRP (r=0.442, p<0.01) had a positive correlation with BMI. In women, triglycerides (r=0.470, p<0.01) and CRP (r=0.366, p<0.01) had a positive correlation with WC. Therefore, WC and SUA may be the most effective anthropometric indices of obesity for screening Korean population.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.2
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• pp.153-159
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• 2006

A 2,656 bp fragment of chicken ghrelin gene was cloned and SNPs were detected by PCR-RFLP and Allele Specific PCR (ASP) in 12 Chinese indigenous chicken breeds and a commercial chicken population. The results showed that there were 23 base variations and an amino acid change ($Gln{\rightarrow}Arg$) in cloned chicken ghrelin gene. Three SNPs were confirmed in 13 populations and associations between this gene and growth traits of Tibetan chicken (TC) and Recessive White chicken (RW) were investigated. The results of haplotype analysis revealed that 26 haplotype genotypes were composed of eight haplotypes. The results of $x^2$ tests indicated that there were significant differences between genotypes or haplotype genotype frequencies in some of the breeds or sexes at 0.05 or 0.01 levels. The results of ANOVA revealed that there were significant differences between genotypes or haplotype genotypes on some growth traits of TC and RW chicken breeds at 0.05 or 0.01 levels. Multiple comparisons showed that there were significant associations between genotype CT at site 71 and some growth traits of two chicken breeds and between genotype AG at site 1,215 and body weight at 16 wk of two chicken breeds, and there was a significant association between haplotype genotype CAA/CAG and body weight and shank girth at 16 wk of two chicken breeds.

• Journal of Ginseng Research
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• v.47 no.2
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• pp.349-351
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• 2023

• Proceedings of the IEEK Conference
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• 2000.06a
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• pp.248-251
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• 2000

The ATM-PON is regarded as an effective access network because the system transmits the various user's information through the passive optical splitter in a single platform. The ranging technology is to place all ONUs at the same distance virtually in order to form ATM-PON based on the Time Division Multiplexing (TDM). In This paper, We show the steps about ranging protocol based on ITU-T G.983.1 and ranging procedure modeling. Also, We implement the simulator that considers various environments to verify the time specifications of G.983.1. By using the simulator, We find out the wasted bandwidth which influences active ONUs during the ranging procedure.

• Journal of electromagnetic engineering and science
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• v.10 no.3
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• pp.179-182
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• 2010

This paper proposed a novel compact bandpass filter with folded half mode substrate integrated waveguide (FHMSIW) cavities using two-layer printed circuit board(PCB) process. The area of the FHMSIW filter is reduced by nearly 50 % and 75 % compared with half mode substrate integrated waveguide(HMSIW) filter and substrate integrated waveguide(SIW) filter, respectively. A four-pole Chebyshev FHMSIW bandpass filter at C-band has been designed, simulated and fabricated. Measured results are presented and found to agree with the full-wave simulated results by using Ansoft HFSS. The filter shows good performance and compact size.