• Communications for Statistical Applications and Methods
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• v.4 no.1
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• pp.229-241
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• 1997

We consider discrimination curve and minimum dwell time for Poisson distribution and Poisson-power function distribution. Let the random variable X has Poisson distribution with mean .lambda.. For the hypothesis testing H$\_$0/:.lambda. = t vs. H$\_$1/:.lambda. = d (d$\_$0/ if X.leq.c. Since a critical value c can not be determined to satisfy both types of errors .alpha. and .beta., we considered discrimination curve that gives the maximum d such that it can be discriminated from t for a given .alpha. and .beta.. We also considered an algorithm to compute the minimum dwell time which is needed to discriminate at the given .alpha. and .beta. for the Poisson counts and proved its convergence property. For the Poisson-power function distribution, we reject H$\_$0/ if X.leq..'{c}.. Since a critical value .'{c}. can not be determined to satisfy both .alpha. and .beta., similar to the Poisson case we considered discrimination curve and computation algorithm to find the minimum dwell time for the Poisson-power function distribution. We prosent this algorithm and an example of computation. It is found that the minimum dwell time algorithm fails for the Poisson-power function distribution if the aiming error variance .sigma.$\^$2/$\_$2/ is too large relative to the variance .sigma.$\^$2/$\_$1/ of the Gaussian distribution of intensity. In other words, if .ell. is too small, we can not find the minimum dwell time for a given .alpha. and .beta..

• Journal of the Korean Applied Science and Technology
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• v.15 no.3
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• pp.61-66
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• 1998

Cyclodextrin are obtained from starch by enzymatic degradation. The three best characterize forms are ${\alpha}$, ${\beta}$, ${\gamma}$ cyclodextrin consisting of 6, 7, and 8 D-glucose units, respectively. Each of the glucose units are in the rigid C1 chair conformation and are linked by ${\alpha}$ 1,4 bonds. This geometry gives the cyclodextrin the shape of a hollow truncated cone with the wider side formed by the secondary 2- and 3-hydroxy groups and the narrower side by the primary 6-hydroxy group. The most characteristics property of the cyclodextrin is their ability to form inclusion complexes with a wide range of guest moleculars. We syntheses per-6-substituted ${\beta}$-cyclodextrin derivatives and investigate structures, spectrospcopic properties. The substituted materials are piperidine, piperazin, morphorine. The synthetic compound showed a good solubility than natural ${\beta}$ cyclodextrin in organic solvents such as methylene chloride, methanol, ethanol, etc.

• Journal of the Korean Ceramic Society
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• v.36 no.1
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• pp.55-60
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• 1999

${\beta}$-SiC thin film was deposited on a Si substrate without buffer layer using a single precursor of Hexamethyldisilane (Si2(CH3)6) by chemical vapor deposition method. HCI gas was introduced into hexamethyldisilane /H2 gas mixture, and the feeding schedule of HCI and precursor gases was modified in order to enhance the selectivity of SiC deposition between a Si substrate and a SiO2 mask. The effect of HCI gas on the surface roughness of the SiC film was investigated and typical electrical properties of the SiC film were also investigated by Hall measurement.

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.22-27
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• 1993

Crude ${\beta}-glucan$ extracted from Barley was purified by stepwide enzyme treatment with thermostable ${\alpha}-amylase$, amyloglucosidase and protease. The thermal properties of Barley ${\beta}-glucan$ were investigated by Differential Scanning Calorimetry. Three endotherms have been observed on DSC thermograms of Barley ${\beta}-glucan$. The first endotherm which produced the gelatinization phenomena commonly observed in Barley ${\beta}-glucan$ became the focus of this study. The temperature range and the enthalpy of gelation exhibited maximum values with increasing concentration of Barley ${\beta}-glucan$. Gelating Barley ${\beta}-glucan$ registered an enthalpy of approximately 0.23 cal/g and exhibited onset temperature (To), peak temperature (Tp) and conclusion temperature (Tc) of $48.8^{\circ}C,\;61.2^{\circ}C\;and\;78.5^{\circ}C$ respectively. The temperature and enthalpy of gelatinizing Barley ${\beta}-glucan$ at both alkali and acid conditions were lower than those at pH 7. With salt present, the Tp and Tc of gelating Barley ${\beta}-glucan$ produced lower temperatures than in conditions where salt was absent, and the enthalpy abruptly decreased. However, increasing salt concentrations did not affect the gelation temperature and the enthalpy of Barley ${\beta}-glucan$. The 'true melting' temperature of Barley ${\beta}-glucan$ was near $184^{\circ}C$ and the melting enthalpy was approximately 34.6 cal/g. The Barley ${\beta}-glucan$ decomposition temperature was in the range of $316^{\circ}C{\sim}346^{\circ}C$.

• Natural Product Sciences
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• v.17 no.4
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• pp.279-284
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• 2011

Phytochemical studies on the whole extract of Sedum hybridum L., a Mongolian medicinal plant, has been undertaken to isolate active principles responsible for its anti-oxidative and antibacterial activities. Eighteen known compounds, i.e. (1) quercetin, (2) kaempferol, (3) herbacetin-8-O-${\beta}$-D-xylopyranoside, (4) myricetin, (5) gossypetin-8-O-${\beta}$-D-xylopyranoside, (6) gallic acid, (7) 2,4,6-tri-O-galloyl-D-glucopyranose, (8) 6-O-galloylarbutin, (9) myricetin-3-O-${\alpha}$-L-arabinofuranoside, (10) quercetin-3-O-${\alpha}$-L-arabinofuranoside, (11) caffeic acid, (12) ethylgallate, (13) (-) epigallocatechin-3-O-gallate, (14) palmitic acid, (15) stearic acid, (16) stearic acid ethyl ether, (17) ${\beta}$-sitosterol and (18) ${\beta}$-sitosteryl-O-${\beta}$-D-glucopyranose have been isolated and their molecular structures identified by spectroscopic analysis. Thirteen substances including seven flavonol components (1, 2, 3, 4, 5, 9 and 10), five gallic acid derivatives (6, 7, 8, 12 and 13) and caffeic acid (11) exhibited significant, dose-dependent, DPPH radical scavenging activity. Galloyl esters 12 and 13 were revealed to be main active principles for the antibacterial property of the extract of Sedum hybridum L.

• IMMUNE NETWORK
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• v.4 no.3
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• pp.161-165
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• 2004

Background: Anti-cardiolipin antibody (Anti-CL Ab) is one of the various antiphospholipid antibodies (Anti-PL Abs) and found in the plasma of patients with systemic lupus erythematosus (SLE), atherosclerosis, and other infectious diseases. While anti-PL Abs found in the sera of patients with infectious diseases bind directly to CL, binding of anti-PL Abs to CL circulating in the sera of patients with autoimmune diseases is mediated by $\beta_2-$glycoprotein 1 ($\beta_2-GP1$). The purpose of this study is to investigate the effect of <$\beta_2-GP1$ on the antigen binding assay of anti-CL Abs present in the sera of patients with atherosclerosis, which has been known as one of autoimmune diseases. Methods: ELISA was performed with sera containing anti-CL Abs from three patients with atherosclerosis in the presence or absence of $\beta_2-GP1$ or FBS. Results: Reactivity of anti-CL Abs to CL was increased in the presence of $\beta_2-GP1$ or FBS in a dose dependent manner. Conclusion: <$\beta_2-GP1$ or FBS could be used as co-factor in CL ELISA with anti-CL Abs present in the sera of patients with atherosclerosis. It is suggested that anti-CL Abs found in atherosclerosis patients are similar in terms of antigen binding property to those circulating in the patients with autoimmune diseases, not to infectious diseases.

• KSBB Journal
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• v.24 no.6
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• pp.584-590
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• 2009

A hot-water extract from fruit body of Auricularia auricula was purified by ethanol precipitation and subsequent dialysis. The polysaccharide showed a typical IR spectrum similar to $\beta$-glucan and was composed of glucose and mannose in a molar ratio of 16.8:83.2 indicating that it is a glucomannan. A glucomannan-like polysaccharide was also identified from Tremella fuciformis. Both of the polysaccahrides showed the presence of acetyl groups and presented colorimetric responses for $\beta$-1,4-glucomannan indicating the acetylated $\beta$-glucomannan similar to the typical polysaccharide found in Aloes.

• Journal of the Korean Ceramic Society
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• v.28 no.5
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• pp.415-421
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• 1991

Influence of Li2O.4B2O3 frit addition on the microstructure and thermal expansion properties of $\beta$-eucryptite ceramics was studied. With 1.0~10.0wt% frit addition, sintering temperature range was enlarged and densified body was obtained. Thermal expansion was increased from -6.67$\times$10-6 $^{\circ}C$-1 of pure sintered body to 1.03$\times$10-6$^{\circ}C$-1 of 6 wt% added body, but this increasement was accompanied by inhibition of thermal expansion anisotropy, so that improved microcracking property.

• Bulletin of the Korean Mathematical Society
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• v.38 no.3
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• pp.449-461
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• 2001

The purpose of this paper is to study several geometric properties for the new class $G_{\kappa}(\beta)$ including geometric interpretation, coefficient estimates, radius of convexity, distortion property and covering theorem.

• Journal of the Korean Society for Heat Treatment
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• v.17 no.4
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• pp.216-222
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• 2004

Study was focused on the quenching embrittlement property of Zircaloy-4 cladding simulated Loss Of Coolant Accident (LOCA) environment in terms of high temperature oxidation and phase transformation. Property in LOCA condition of advanced cladding that contained Nb element was also investigated. Claddings were oxidized at given temperature and given time followed by water quenching. The results showed that ${\beta}$ phase which formed at quenching stage has an influence on cladding property. In case of advanced cladding, Nb retards cladding oxidation, thus enhances quenching resistance.