• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.11
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• pp.1706-1712
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• 2012

The Beta-ray absorption method (BAM) gives a good solution for measuring the mass concentration of atmospheric particles(PM10 and PM2.5). To determine particular matters (PM) concentration, a ratio of the number of detected beta-ray intensity passing through the clean filter and the dust-sampled filter is used. These intensity data measured in air pollution monitoring such as PM10 and PM2.5 usually contained the additive noise(thermal noise, power supply noise and etc.). Therefore, the estimation performance of mass concentration can be deteriorated by these noises. In this paper, we present a new noise reduction method that is essentially required to develope an automatic continuous PM monitoring system using beta-ray absorption method. By combining the block data averaging technique and curve fitting, in the proposed method, the additive noise can be reduced in the measured data. To evaluate the performance of the proposed method, computer simulations were performed with computer generated signals as the input.

• Journal of the Korean Society of Safety
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• v.9 no.3
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• pp.22-27
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• 1994

For the $\beta$=1 specimen with constant thickness, Crack growth rate is smoothly increasing in the a-N curve. On the other hand for $\beta$=2 specimen with various thickness, the inflection point is observed in crack growth rate near the thickness interface. da/dN before the inflection point is increased, and da/dN after the point is decreased, compared to the $\beta$=1 specimen. da/dN near the thickness interface is approached zero. The descending point was observed earlier as $\beta$ increased. Considering the relation between da/dN and λ, the crack propagation rates for the case of $\beta$ =1 incrased almost linearly, however, the crack propagation rates for $\beta$=2,3 decreased more rapidly near the thickness interface. Additionally, the decreased point in da/dN for $\beta$=3 is farther from the thickness interface than the case for $\beta$ =2.

• Journal of radiological science and technology
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• v.8 no.2
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• pp.77-81
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• 1985

In this experiments the operation of the Geiger-Mueller tube is investigated by measuring the relationship between the count rate and the applied voltages, The length and slope of the plateau are characteristic of the tube. In our experiments, the average plateau length of the tube is extend for about 100 [V] and the slope 0.017 [%/V]. For normal counting purposes the working voltage is usually selected at value about 50 volts larger than the threshold of the plateau. To investigate the absorption of beta particles by matter. We performed an absorption experiments by using the Al absorber and Sr-90 ($0.125{\mu}Ci$) beta source. The maximum range of the beta radiation can be determined by visual extrapolation of the curve after subtraction of the constant background-rate and the maximum beta energy 2.09 [MeV] can be calculated from the range using an experimental relation.

• Progress in Medical Physics
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• v.3 no.1
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• pp.9-18
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• 1992

In this study, beta-eucryptite is fabricated and the thermal parameters of this material have been investigated. The thermoluminescence from 4MeV X-ray irradiated beta-eucryptite have been measured over the temperature range of 300K-600K. Thermoluminescence curve from X-ray irradiated beta-eucryptite shows five peaks located at 342K, 392K, 438K, 474K, and 527K. $\tau$, $\delta$ and $\omega$ of peak at 527K are 35K, 39K and 74K, respectively and this peak is found to be 2nd order kinetics. The activation energy of peak shape method is calculated to be 1.03eV and the frequency factor for 527K curve is calculated to be 3.9x10$\^$8/sec$\^$-1/. Based on the various heating rates methods, the activation energy of the peak is computed to be 1.02${\pm}$0.05eV that is similar to 1.19${\pm}$0.03eV of initial rise method. The linearity of thermoluminescence intensity and radiation flux is valid up to 50Gy and beyond higher dose the supralinearity and saturation come out.

• Journal of the Korean Society of Safety
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• v.13 no.4
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• pp.172-179
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• 1998

The effects of $^{60}Co\;{\gamma}-Ray$ irradiation on TSC characteristics of TFE type polytetrafluoroethylene(PTFE) were investigated. The $\alpha$ peak on TSC curve of PTFE was decreased, while the $\beta$ peak was reversely increased by the increasing of $\gamma$-irradiation doses up to 80 krad(0.8 kGy). Moreover, $\alpha$ and $\beta$ peaks on TSC curve of the irradiated PTFE are changed with the increasing of the forming temperature and forming electric field. In annealing the irradiated PTFE specimens at room temperature in air, it was shown a continuous recovery of TSC characteristics with time, which is assumed the traped charge carriers are liberated from the shallow traps and undergoes a recombination process during room temperature decay.

• Journal of the Korean Chemical Society
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• v.15 no.5
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• pp.241-245
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• 1971

Endothermic peak of transformation of ${\gamma}-MnO_2$ was obviously shown by differential heating curve in the present study, and the transformation temperature was different from other modification. ${\gamma}-MnO_2$ carried out to analyze exclusively, by means of the half area method in corresponding endothermic peak of differential heating curve. ${\alpha}-\;and\;{$beta}-MnO_2$ (Pyrolusite) containing in sample about 75% is interfered about ${\pm}$10% of the relative error, and while those of below 50% is interfered about ${\pm}$5%.

• Microbiology and Biotechnology Letters
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• v.23 no.5
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• pp.513-518
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• 1995

To evaluate bile salt-tolerance of lactic acid bacteria (LAB, Lactobacillus acidophilus ATCC 4356, Lactobacillus casei IFO 3533, Streptococcus thermnophilus KCTC 2185, Lactobacillus lactis ATCC 4797, and Lactobacillus bulgaricus ATCC 11842), We investigated the survivals, acid production and $\beta $-galactosidase activity of LAB under anaerobic broth system. Cellular permeability of LAB and their cellular retention of $\beta $-galactosidase were also examined in the same system. Although the growth of LAB was slightly suppressed by 0.3% bile salt, they showed normal growth curve. Streptococcus thermophilus KCTC 2185 was significantly more resistant to bile salt than the others. The $\beta $-galactosidase activity from Streptococcus thermophilus KCTC 2185 and Lactobacillus bulgaricus ATCC 11842 and their cellular retention of $\beta $-galactosidase decreased by 0.3% bile salt. The cellular permeability of LAB in the presence of bile salt increased significantly.

• Analytical Science and Technology
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• v.6 no.4
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• pp.375-381
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• 1993

The efficiencies of four different solid absorbents were evaluated for the simultaneous solid-phase extraction of six ${\beta}$-blockers from biological sample. Chromosorb 107 using methanol as the eluting solvent gave the highest solid-phase extraction yield. From the breakthrough studies of ${\beta}$-blockers, the excellent sorption and desorption properties of the Chromosorb 107 column were verified. The usefulness of Chromosorb 107/methanol was examined for the simultaneous solid-phase extraction of the ${\beta}$-blockers from serum in the concentration range of 2~8ppm.

• Journal of Pharmaceutical Investigation
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• v.18 no.1
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• pp.15-21
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• 1988

An inclusion complex of phenytoin (PT) with ${\beta}-cyclodextrin\;({\beta}-CyD)$ in molar ratio of 1 : 1 was prepared, and the interaction between host and guest molecules was confirmed by infrared spectrometry, differential scanning calorimetry and X-ray diffractometry. Suppositories were prepared by the fusion method. PT and $PT-{\beta}-CyD$ complex were added to PEG 1540 and Witepsol H-15 under the vigorous stirring at $40^{\circ}C$. Content uniformity was tested for different formulations of the PT suppositories. The release rates were dependent on the K.P. V dissolution apparatus and the dialyzing tubing method. Then, the release rates were increased in the following order: $PT-{\beta}-CyD$ complex in PEG 1540>PT in PEG 1540>$PT-{\beta}-CyD$ complex in Witepsol H-15>PT in Witepsol H-15. The area under the curve and maximum blood concentration after rectal administration were increased in the following order: $PT-{\beta}-CyD$ complex in PEG 1540>PT in PEG 1540>$PT-{\beta}-CyD$ complex in Witepsol H-15>PT in Witepsol-15.

• Journal of Pharmaceutical Investigation
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• v.23 no.1
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• pp.11-18
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• 1993

Inclusion complex of ibuprofen with $2-Hydroxypropyl-{\beta}-cyclodextrin\;(HP-{\beta}-CD)$ in aqueous solution and in the solid state was evaluated by the solubility method and the instrumental analysis such as infrared spectroscopy, thermal analysis and x-ray diffractometry. The aqueous solubility of ibuprofen was increased linearly with the increase in the concentration of $HP-{\beta}-CD$, showing an $A_L$ type phase solubility diagram. The results showed that the dissolution rate of ibuprofen was significantly increased by complexation with $HP-{\beta}-CD$. $Ibuprofen-HP-{\beta}-CD$ complex enhanced the mean plasma concentration levels and the area under plasma concentration-time curve after oral administration compared to those of the drug alone. It is concluded that the complex of ibuprofen with $HP-{\beta}-CD$ increases the dissolution rate and improves the bioavailability of the ibuprofen by the formation of a water-soluble complex.