• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.383-386
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• 1993

In this paper, we propose a sensory data combination method by a fuzzy number approach for multisensor data fusion. Generally, the weighting of one sensory data with respect to another is derived from measures of the relative reliabilities of the two sensory modules. But the relative weight of two sensory data can be approximately determined through human experiences or insufficient experimental data without difficulty. We represent these relative weight using appropriate fuzzy numbers as well as sensory data itself. Using the relative weight, which is subjective valuation, and a fuzzy-numbered sensor data, the fuzzy weighted average method is used for a representative sensory data. The manipulation and calculation of fuzzy numbers can be carried out using the Zadeh's extension principle which can be approximately implemented by the $\alpha$-cut representation of fuzzy numbers and interval analysis.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.2
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• pp.260-265
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• 1999

$SiC/Si_3N_4$ composites were prepared by mixing ${\alpha}-Si_3N_4$ powder to $\alpha$-SiC powder in the range of 10 to 30 vol% with 10 vol% interval. 6 wt% of $Al_2O_3$ and $Y_2O_3$ were also added respectively as sintering aids. Then, pressureless sintering was performed at 1,78$0^{\circ}C$ for 2 hours in $N_2$ gas. In the case of adding 20 vol% of ${\alpha}-Si_3N_4$ powder, the relative desity to theoretical value and the flexutal strength were 92 % and 3,560 MPa, respectively. The smallest relative worn amount thereof was $2.68{\times}10^{-3}\;mm^2$ for 20 vol% ${\alpha}-Si_3N_4$. The composite containing 30 vol % of ${\alpha}-Si_3N_4$ powder showed the highest fracture toughness $(K_{1c})$ of $4.9\;MN/m^{3/2}$, although the reduction of the wear resistance due to the effect of the pores was observed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.2
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• pp.137-143
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• 2008

Rapid canopy closure (RCC) is one of the physiological attributes that may enhance genetic yield potential of rice (Oryza sativa L.) in a growing season. Crop growth before canopy closure could be described by an exponential equation of $y\;=\;{\alpha}{\cdot}{\exp}({\beta}{\cdot}t)$ where $\alpha$ is the crop leaf area index (LAI) or shoot dry weight (DW), t is the thermal time, $\beta$ is the LAI or DW at the beginning of the exponential growth and is the relative growth rate of LAI ($m^2m^{-2}^{\circ}C^{-1}$) or DW($gg^{-2}^{\circ}C^{-1}$). Field experiment using 22 cultivars revealed that the exponential growth phase before canopy closure can be divided into two sections; an earlier section during which crop dry weight and LAI of varieties are highly dependent on $\alpha$ and a second section where crop dry weight and LAI are highly dependent on $\beta$. Grain weight had significantly positive correlation with $\alpha$ parameter and dry weight and LAI during early exponential phase. The parameter $\beta$ of the exponential growth curve had positive and significant correlation with the LAI and dry weight during the late exponential growth phase, grain number per unit area, and grain yield. There was genotypic difference for RCC parameters, $\alpha$ and $\beta$, indicating the possibility of genetic improvement for these traits.

• Journal of the Korean Chemical Society
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• v.27 no.4
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• pp.279-286
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• 1983

An apparatus was made for the electrodeposition of alpha emitting actinide nuclides, $^{207}Bi$ and $^{210}Po$. The electrodeposition was made on a polished stainless steel plate cathode. The anode was made of platinum wire and to stir the solution. With the ammonium chloride as electrolyte initial pH = 4, chloride concentration = 0.6M and solution volume = 15ml, a current of 1.5 ampere(current density = 0.59A/$cm^2$) was flowed for 100 minutes for the quantitative recovery of electrodeposition and on average recovery of 98.3% was obtained within ${\pm}$0.7% uncertainty. Alpha spectrometry of the electrodeposited sample showed alpha peaks from $^{210}Po, ^{234}U$ and $^{239}Pu$ having energy resolution (FWHM) of 18.3, 21.8 and 36.0 keV respectively. The electrodeposition and alpha spectrometry for a natural uranium sample of domestic origin gave $^{238}U : ^{234}U = 1 : 6.1{\times}10^{-5}$ and for a neutron-irradiated uranium sample did $^{238}U : ^{239}Pu : ^{241}Am = 100 : 0.0263 : 5.20{times}10^{-5}$. The result of $^{238}U$ determination in the irradiated sample by electrodeposition-alpha spectrometry was in accord within ${\pm}1.6%$ of relative error with the results of solid fluorimetry and mass spectrometry. For $^{239}Pu$ the result of electrodeposition-alpha spectrometry was in accord within ${\pm}$4.0% of relative error with the results of anion exchange separation and the thenoyltrifluoroacetone(TTA) extraction both followed by alpha spectrometries.

• Journal of Aquaculture
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• v.9 no.1
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• pp.57-63
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• 1996

The relative effectiveness of steroids and human chorionic gonadotropin (HCG) on germinal vesicle breakdown (GVBD) was investigated in vitro using the isolated oocytes (folliculated oocytes) from the spotted halibut, Verasper variegatus. Among the steroids tested, $17\alpha-hydroxy,\;20\beta-dihydroprogesterone\;(17\alpha20{\beta}OHP)$ was more effective than progesterone (P4) and $17\alpha-hydroxyprogesterone\;(17{\alpha}OHP$). In comparing $17\alpha,\;20{\beta}OHP$ with HCG, both $17\alpha20{\beta}OHP$ and HCG were effective in inducing GVBD at all concentrations : $17\alpha20{\beta}OHP$ was effective even at lower concentrations ($10\~50$ ng/ml). HCG at three concentrations used (50, 100, 500 IU/ml) showed no significant differences in inducing GVBD.

• Journal of the Korean Society of Safety
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• v.25 no.3
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• pp.123-130
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• 2010

Electroencephalogram(EEG) would be the most objective psychophysiological research technique on human errors though few research has been taken yet. This study aimed to get characteristics of human error while committing simple Odd-Ball tasks by utilizing the power spectrum technique of EEG data. Each experiment was composed of 3 tasks with different rules, and 8 young undergraduate students participated in this study as paid subjects. The result showed in the affirmative that subject and the interaction of subject and task factors were statistically significant on variation of $\alpha$ band power $P_{\alpha/(\alpha+\beta+\theta)}$ and $\beta$ band power $P_{\beta/(\alpha+\beta+\theta)}$, and that the former increasing in backward direction to Pz reflects compatibility whereas the latter increasing in forward direction to Fz reflects familiarity. Therefore it was coucluded that, since task 2 carried out in the present research requiring decoding process would be more difficult to human beings than the task merely requiring psychological recall process, task 1 and task 3 were classified into a homogenious group excluding task 2, and the ratio $\alpha$ band power to $\beta$ band power indicated enormous increase of $\alpha$ band power relative to $\beta$ band power in the cases of contra-lateral errors, especially in task 2.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.18 no.1
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• pp.1-12
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• 2005

Melanin determines phenotypic appearance and its election-opaque property protects cells from physical, including ultraviolet (UV) radiation, and chemical stimuli such as free radicals. However hyper-pigmentation is associated with various skin diseases such as keloid scar. The aim of present study was to investigate the effects of aqueous extracts from Angelica dahurica Benth. (AEAD) on ${\alpha}-Melanocyte$ stimulating hormone $({\alpha}-MSH)-induced$ melanogenesis in B16 mouse melanoma cell. Relative high doses ($5\;mg/m{\ell}$) of AEAD could inhibit melanin formation without apoptotic death in cells treated with ${\alpha}-MSH$. And also, ${\alpha}-MSH-induced$ activation of tyrosinase was inhibited in cells treated with AEAD. These results suggest that AEAD inhibit melanogenesis through inhibiting tyrosinase activity, and also, AEAD may apply to develop whitening drugs and cosmetics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.367-375
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• 1998

The physicochemical properties of the $\alpha$-amylase inhibitors from black bean and naked barley is Korea were investigated. Preincubation time for maximum inhibition was 30min and no activity change was seen after that time. Optimum pH of the $\alpha$-amylase inhibitors from the black bean and naked barley was pH 7.0 and the inhibitory activities were stable in the range of pH 6.0~8.0 in both phosphate and Tris-HCI buffer solutions. Both inhibitors maintained more than 50% of activity after incubation for 17 min at 7$0^{\circ}C$. The inhibitors from the black bean and naked barley maintained more than 50% of activities after treatment for 40 min and 30 min with pepsin, and 30 min and 50 min with trypsin, respectively. Both inhibitors functioned via a noncompetitive mechanism and were active against porcine pancreatic and human salivary $\alpha$-amylases. The activities of both inhibitors were linear for the ionic stength ranging from 0 to 0.9. The addition of 70 mM maltose to the reaction mixture caused a maximum increase in the relative activities of both inhibitors, but it did not affect the dissociation of the EI complex. The activities of both inhibitors were significantly enhanced by adding 1mM of K+ or Mg2+.

• Journal of the Korean Wood Science and Technology
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• v.42 no.2
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• pp.149-156
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• 2014

Termites are wood pests that cause vast economic damage every year. They digest both cellulose and starch, but the enzymes for starch digestion have not been well characterized. We obtained complete amino acid sequence information on the KME1 ${\alpha}$-amylase from Reticulitermes speratus KMT1 through analysis of total mRNA sequences. The KME1 enzyme has two ${\alpha}$-amylase domains and is 68% identical to the ${\alpha}$-amylase from Blattellager manica, its closest relative in the GenBank database. Some unique features of its conserved region and its distant evolutionary relationship to other insect ${\alpha}$-amylases suggest that KME1 is a new type of ${\alpha}$-amylase.

• YAKHAK HOEJI
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• v.36 no.4
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• pp.370-378
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• 1992

A simple and sensitive high performance liquid chromatographic method to quantitate ${\alpha}-keto$ acids in serum and urine was investigated. ${\alpha}-Keto$ acids react with 1,2-diamino-4,5-methylenedioxybenzene (DMB) in the presence of 2-mercapto-ethanol and sodium hydrogen sulfite to form highly fluorescent derivatives, substituted 6,7-methylenedioxyquinoxalinol. The derivatization procedure was performed in water bath at $100^{\circ}C$, and completed within 50 min. By the use of a reversed-phase column and multi-step gradient with two solvents, a mixture containing twelve of these derivatives were efficiently resolved within 35 minutes. The optimal wavelengh of the fluorescence detector are ${\lambda}_{ex}=364\;nm$ and ${\lambda}_{em}=445\;nm$. The quantitation of the individual ${\alpha}-Keto$ acids was reproducible with relative standard deviation of $3.0{\sim}7.9%$ and had a detection limits of $10{\sim}60$ fmol, except for p-hydroxyphenylpyruvic acid (960 fmol).