• Tunnel and Underground Space
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• v.11 no.1
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• pp.72-78
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• 2001

A method to determine elastic constants for transversely isotropic rock using a single uniaxial compression test was proposed by Kim(1995). However, some problems were found when this method was applied. We derived two different equations in determination of elastic constants using V$\sub$12/ and V$\sub$21/ and performed uniaxial compression tests for two specimens whose angles between transversely isotropic plane and horizontal plane are 30$^{\circ}C$ and 65$^{\circ}C$. The anisotropic elastic constants should be calculated with different equations depend on the angle. If the anisotropic angle is lower than 45$^{\circ}$, V$\sub$21/ may be used. However, if the anisotropic angle is higher than 45$^{\circ}$, V$\sub$12/ may be used.

• Progress in Medical Physics
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• v.25 no.3
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• pp.185-192
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• 2014

The purpose of this study is to evaluate the results for the quality assurance through a statistical analysis on the output characteristics of linear accelerators belonging to Yeungnam University Medical Center by using the Shewhart-type chart, Exponentially weighted moving average chart (EWMA) chart, and process capability indices $C_p$ and $C_{pk}$. To achieve this, we used the output values measured using respective treatment devices (21EX, 21EX-S, and Novalis Tx) by medical physicists every month from September, 2012 to April, 2014. The output characteristics of treatment devices followed the IAEA TRS-398 guidelines, and the measurements included photon beams of 6 MV, 10 MV, and 15 MV and electron beams of 4 MeV, 6 MeV, 9 MeV, 12 MeV, 16MeV, and 20 MeV. The statistical analysis was done for the output characteristics measured, and was corrected every month. The width of control limit of weighting factors and measurement values were calculated as ${\lambda}=0.10$ and L=2.703, respectively; and the process capability indices $C_p$ and $C_{pk}$ were greater than or equal to 1 for all energies of the linear accelerators (21EX, 21EX-S, and Novalis Tx). Measured values of output doses with drastic and minor changes were found through the Shewhart-type chart and EWMA chart, respectively. The process capability indices $C_p$ and $C_{pk}$ of the treatment devices in our institution were, respectively, 2.384 and 2.136 for 21EX, 1.917 and 1.682 for 21EX-S, and 2.895 and 2.473 for Novalis Tx, proving that Novalis Tx has the most stable and accurate output characteristics.

• Corrosion Science and Technology
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• v.21 no.4
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• pp.290-299
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• 2022

Anodizing is an electrochemical surface treatment method conferring corrosion resistance and durability by forming a thick anodization film on the metal surface. Aluminum has a long service life and high thermal conductivity and formability, as well as excellent corrosion resistance. Aluminum 3003 alloy has improved formability, strength, and corrosion resistance due to the addition of a small amount of manganese. However, corrosion occurs in seawater and environments polluted with corrosion-inducing substances, which reduce corrosion resistance. Therefore, it is necessary to artificially form a thick anodized film to improve corrosion resistance. In this study, the anodization treatment time was 4 minutes, and voltages of 10 V, 20 V, 30 V, 40 V, 50 V, 60 V, 70 V, 80 V, 90 V, and 100 V were applied. The thickness and pore size of the oxide film increased according to the applied voltage. A barrier film was formed under voltage conditions from 10 V to 50 V, and a porous film was formed under voltage conditions from 60 V to 100 V. After anodizing, coating was applied. Wettability and corrosion resistance were observed before and after coating according to the surface shape and thickness of the oxide film.

• Journal of Microbiology and Biotechnology
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• v.22 no.10
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• pp.1423-1431
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• 2012

The inhibitory effect of IgY against Vibrio parahaemolyticus and Vibrio vulnificus responsible for seafood-borne diseases was investigated in this study. Water-soluble fractions (WSF) of protein containing IgYs were isolated from the egg yolk of hens initially immunized with formalin-inactivated V. parahaemolyticus or V. vulnificus. Protein, total and specific IgY contents of the WSF were determined. The inhibitory and protective effects of IgYs on the growth of V. parahaemolyticus and V. vulnificus were assayed in liquid medium and in mice. IgYs showed high affinity to their corresponding antigens with high titer from day 28 onwards. Protein contents and total IgY concentrations remained stable throughout the immunization period, whereas specific IgY concentrations increased steadily and reached a plateau at day 49. Specific IgY powder (150 mg/ml) significantly inhibited further multiplication of both V. parahaemolyticus and V. vulnificus in liquid medium as compared with the control IgY. The bacteria count in mice feces was lower in mice pretreated with specific IgYs than in those pretreated with PBS or control IgY. Higher survival of mice was observed in the experimental groups pretreated with either anti-V. parahaemolyticus (75% survival) or anti-V. vulnificus (87% survival) IgYs, compared with those in the control groups pretreated with PBS or nonspecific IgY. All mice in the control groups died within three days after bacteria inoculation; hence, the protective effect of specific IgYs against infection caused by V. parahaemolyticus and V. vulnificus was demonstrated.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.11
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• pp.21-27
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• 2004

In this paper, millimeter-wave monolithic integrated circuit(MIMIC) low noise amplifier(LNA) for V-band, which is applicable to 60 GHz wireless local area network(WLAN), was fabricated using the high performance 0.1 ${\mu}{\textrm}{m}$ $\Gamma$-gate pseudomorphic high electron mobility transistor(PHEMT). The DC characteristics of PHEMT are drain saturation current density(Idss) of 450 mA/mm and maximum transconductance(gm, max) of 363.6 mS/mm. The RF characteristics were obtained the current gain cut-off frequency(fT) of 113 GHz and the maximum oscillation frequency(fmax) of 180 GHz. V-band MIMIC LNA was designed using active and passive device library, which is composed of 0.1 ${\mu}{\textrm}{m}$ $\Gamma$-gate PHEMT and coplanar waveguide(CPW) technology. The designed V-band MIMIC LNA was fabricated using integrated unit processes of active and passive device. The measured results of V-band MIMIC LNA are shown S21 gain of 21.3 dB, S11 of -10.6 dB at 60 GHz and S22 of -29.7 dB at 62.5 GHz. The measured result of V-band MIMIC LNA was shown noise figure (NF) of 4.23 dB at 60 GHz.

• Bulletin of the Korean Chemical Society
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• v.21 no.9
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• pp.913-918
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• 2000

Vanadium oxide catalyst supported on TiO2-ZrO2 has been prepared by adding Ti(OH)4-Zr(OH)4 powder to an aqueous solution of ammonium metavanadate followed by drying and calcining at high temperatures. The char-acterization ofthe prepared catalysts was performed using solid-state 51V NMR and FTIR.In thecase ofcalci-nation temperature at 773 K, vanadium oxide was in a highly dispersed state for the samples containing low loading V2O5 below 25 wt %, but for samplescontaining high loading V2O5 equal to or above 25 wt %, vana-dium oxidewas well crystallized due to the V2O5 loading exceeding the formation of monolayer on the surface of TiO2-ZrO2.The ZrV2O7 compound was formed through the reactionof V2O5 and ZrO2 at 773-973 K, where-as the V3Ti6O17 compound was formedthrough the reaction of V2O5 and TiO2 at 973-1073 K. The V3Ti6O17 compound decomposed to V2O5 and TiO2 at 1173 K, which were confirmed by FTIR and 51V NMR.

• IMMUNE NETWORK
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• v.21 no.5
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• pp.32.1-32.14
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• 2021

Over two hundred twenty-eight million cases of coronavirus disease 2019 (COVID-19) in the world have been reported until the 21^st of September 2021 after the first rise in December 2019. The virus caused the disease called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Over 4 million deaths blame COVID-19 during the last one year and 8 months in the world. Currently, four SARS-CoV-2 variants of concern are mainly focused by pandemic studies with limited experiments to translate the infectivity and pathogenicity of each variant. The SARS-CoV-2 α, β, γ, and δ variant of concern was originated from United Kingdom, South Africa, Brazil/Japan, and India, respectively. The classification of SARS-CoV-2 variant is based on the mutation in spike (S) gene on the envelop of SARS-CoV-2. This review describes four SARS-CoV-2 α, β, γ, and δ variants of concern including SARS-CoV-2 ε, ζ, η, ι, κ, and B.1.617.3 variants of interest and alert. Recently, SARS-CoV-2 δ variant prevails over different countries that have 3 unique mutation sites: E156del/R158G in the N-terminal domain and T478K in a crucial receptor binding domain. A particular mutation in the functional domain of the S gene is probably associated with the infectivity and pathogenesis of the SARS-CoV-2 variant.

• Radiation Oncology Journal
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• v.9 no.2
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• pp.337-342
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• 1991

The comparison of the KAPM Dosimetric Protocol (1990) with the TG-21 and $C_{\lambda}/C_E$(ICRU-21 and SCRAD protocol) method is studied. The therapetutic range of radiation (photon 4MV-l5MV and electron 6 MeV-20MeV) and three kinds of the chambers were used in the water phantom. The results from 7G-21 and KAPM protocol did not show much differences (less than 1$\%$) throughout the whole energy range; $N_D$ from KAPM protocol and Ngas from TG-21 showed 0.2$\%$ deviation mainly from W/e difference between two protocols. But the results from KAPM protocol (1990) and those from $C_{\lambda}/C_E$ Method showed $-1.9{\pm}0.6\%$ (KAPM protocol is higher) deviation for photom beam and $+3.3{\pm}1\%$ (KAPM protocol is lower) deviation for electron beams.

• Biomedical Science Letters
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• v.18 no.3
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• pp.210-217
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• 2012

Oncolytic viral vectors have shown good candidates for cancer treatment but have many limitations. To improve the therapeutic potential of oncolytic vaccinia virus, we developed a recombinant vaccinia virus expressing the 4-1BBL co-stimulatory molecule or CCL21. 4-1BBL and CCL21 expression was identified by FACS analysis and immunoblotting. rV-4-1BBL vaccination shows significant tumor regression compared to rV-LacZ, but rV-CCL21 shows rapid tumor growth compared to rV-LacZ in the poorly immunogenic B16 murine melanoma model. 4-1BBL expression resulted in the increase of the number of CD8+ T cells and especially the increase of effector (CD62L-CD44+) CD8+ T cells. These data suggest 4-1BBL may be the potential target for enhancement of tumor immunotherapy.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.587-587
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• 2012

Supercapacitors, which can deliver significant energy with high power density, have attracted a lot of attention due to their potential application in energy storage. Among various oxide materials, sodium vanadate has been recognized as one of the most promising electrode materials because of high electrical conductivity. In addition, larger layer spacing of ${\beta}$-Na0.33V2O5 compared to V2O5 makes easier Li+ insertion. Moreover, ${\beta}$-Na0.33V2O5 has a tunnel like structure along b axis with 3 kinds of V site allowing it to enhance the ion intercalation by introducing three different intercalation sites along the tunnel. The tunnel can act as a fast diffusion path for ion diffusion, which can improve the overall charge storage kinetics. In this study, high quality single crystalline sodium vanadate (${\beta}$-Na0.33V2O5) nanowires were grown directly on Pt coated $SiO_2$ substrate by a facile chemical solution deposition method without employing catalyst, surfactant or carrier gas. The results show that great enhancement in capacitance was observed compared with previous reports.