• Journal of the Korean Society for Railway
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• v.9 no.3 s.34
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• pp.291-297
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• 2006

The present study investigated the effect of fire suppression using a mid-low pressure water mist in a carriage fire. The fire extinguishing time and temperature distributions below ceiling in the enclosed compartment of $2.9m{\times}2.8m{\times}5.0m$ were measured by stopwatch and k-type thermocouples for various fire positions. The numerical simulations were extensively performed using. Fire Dynamics Simulator(FDS, Ver. 4.0) code and the predictions were compared with experimental data. The prediction results showed good agreement with the measured maximum temperature in the all cases. Whereas the predicted temperature was about $40^{\circ}C$ higher than the measured one after operating of water mist. The predicted fire extinguishing times were compared with those of measured data. Fires are extinguished within 200 seconds at the experiment in Case 2 and Case 3. But in Case 1 fire was not extinguished in the numerical simulation. The reason of the discrepancy between predicted and measured data was that a simple suppression algorithm has been implemented in FDS. Also, various databases of fire properties for combustible materials and more elaborate model considering the water mist were required fur better predictions of the cooling and suffocation effect.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.703-712
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• 2004

A variant of the magnetoplasma jet engine (magjet) is here proposed for airbreathing flight in the hypersonic regime. As shown in Figure 1, the engine consists of two distinct ducts: the high-speed duct, in which power is added electromagnetically to the incoming air by a momentum addition device, and the fuel cell duct in which the flow stagnation temperature is reduced by extracting energy through the use of a magnetoplas-madynamic (MPD) generator. The power generated is then used to accelerate the flow exiting the fuel cells with a fraction bypassed to the high-speed duct. The analysis is performed using a quasi one-dimensional model neglecting the Hall and ion slip effects, and fix-ing the fuel cell efficiency to 0.6. Results obtained show that the specific impulse of the magjet is at least equal to and up to 3 times the one of a turbojet, ram-jet, or scramjet in their respective flight Mach number range. Should the air stagnation temperature in the fuel cell compartment not exceed 5 times the incoming air static temperature, the maximal flight Mach number possible would vary between 6.5 and 15 for a magnitude of the ratio between the Joule heating and the work interaction in the MPD generator varied between 0.25 and 0.01, respectively. Increasing the mass flow rate ratio between the high speed and fuel cell ducts from 0.2 to 20 increases the engine efficiency by as much as 3 times in the lower supersonic range, while resulting in a less than 10% increase for a flight Mach number exceeding 8.

• The Journal of the Acoustical Society of Korea
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• v.27 no.3
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• pp.103-110
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• 2008

Strategically, the Patrol Killer Medium (PKM) ought to run at high speed that produces largely vibration by propeller, in a consequence, the vibration gradually deterioratescrews' working condition and increases the possibility of SONAR detection. In this paper, we propose the propeller damper, which is one of waysto reduce the vibration induced by the propeller, and simulate the ability of the damper numerically. The propeller damper was designed to apply to an isolated plate at the bottom flat board of ship which is directly affected by the fluctuating pressure. The dynamic pressure for the stern part of the PKM is calculated by using the DnV rule and the numerical analysis when the propeller damper applied or not, is performed with ANSYS at the isolated plate that simplified. From the analysis, the damping effect of the proposed propeller damper is confirmed and the reduction ratio for each compartment is estimated based on the experimental data in the PKM.

• The Korean Journal of Nuclear Medicine
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• v.28 no.3
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• pp.364-370
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• 1994

The purpose of this study is to evaluate the clinical application of the no carrier added $[^{51}Cr]Cr(III)$-EDTA complexes, produced at Korea Cancer Center Hospital. The $[^{51}Cr]Cr(III)$-EDTA complexes, usefut for measurement of GFR were prepared at room temperature in the presence of bicarbonate catalysts. The radiochemical purity of $[^{51}Cr]Cr(III)$-EDTA was over 99% by paper electrophoresis. The time activity curves were obtained by counting the blood samples from 5 volunteers and counting the head and neck regions with whole body counter after injection of the $^{51}Cr$-EDTA, respectively. After the nonlinear regression, the area under curve was obtained. The plasma clearance of the $^{51}Cr$-EDTA was calculated with injected dose/AUC. The clearance rate calculated with the head and neck counting data was in good agreement with the result from the plasma sample radioactivity at 1-3 hrs after injection. From this result, the counting of head and neck region and the nonlinear regression by 2-compartment model could be applied for the measurement of the clearance rate. Using MIRD system, the absorbed radiation dose was calculated by residence $time{\times}S$. The absorbed whole body radiation dose was negligibly small.

• KSBB Journal
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• v.14 no.1
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• pp.82-90
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• 1999

In order to eventually fabricate an analytical system for infectious microorganisms, we synthesized major immunochemical components, utilized them for the construction of model system, and investigated an assay concept for bacterial whole cells. For the preparation of system components, a polyclonal antibody, against Salmonella thompson as model analyte, purified by immuno-affinity chromatography was used to chemically link to streptavidin or an enzyme, horseradish peroxidase(HRP). The antibody and streptavidin was modified with sulfosuccinimidyl 4-[N-maleimidomethyl]cyclohexane-1-carboxylate and N-succinimidyl-3-[2-pyridyldithio]propionate(subsequently activated by dithiotheritol), respectively. The modified components were reacted to synthesize antibody-streptavidin conjugates which were then purified on a two-layer chromatography column of diaminobiotin gel and Sephadex G-100. For antibody-HRP conjugates, HRP molecules were activated by $NalO_4$ oxidation and then coupled to immunoglobulin. After stabilizing with ($NaCNBH_3$, the conjugates were purified by size exclusion chromatography on Biogel A5M column. To devise a model system, such produced components were combined with a dot-blotter in which a nitrocellulose membrane($12{\mu}m$ pre size) with immobilized biotin was already located. The analyte (S. thompson cells) was reacted with the both antibody conjugates in a liquid phase, and the complexes formed were captured on the membrane surfaces by applying vacuum in the bottom compartment of the blotter to invoke biotin-streptavidin reaction. Under optimal conditions, the system enabled to identify the analytical concept for bacterial whole cells, and the lower limit of detection was approximately $1{\mu}g/m{\ell}$($10^5-10^6$ cells/m$m{\ell}$). The controlling factors were the concentrations of each antibody conjugate that caused agglutination in the presence of analyte as they increased.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.6 no.1
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• pp.10-19
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• 2020

Boron Neutron Capture Therapy (BNCT) has the advantage of selectively removing cancer cells ingesting boron compounds. In this study, the benefits for treatment time and boron compound injection dose were compared between current neutron sources and a high current neutron sources to be developed in near future. The time-activity curve (TAC) of GBM (Glioblastoma) for one bolus injection was obtained by applying modified 3 compartment model. The treatment time was determined for an accelerator-based neutron sources at the present time and a high current accelerator based neutron source to be developed in the near future. In the case of the double amount of IAEA-recommended neutron flux, the treatment time was shortened to 15 minutes. In the case of high current accelerators, which are five times the amount of IAEA-recommended neutron flux, the irradiation time is within 5 minutes. The use of a high current accelerator based neutron source in BNCT is advantageous in terms of treatment time. In addition, it can increase the efficiency of use of neutrons and reduce the boron compound injection dose to patients, thus reducing pharmacological toxicity.

• YAKHAK HOEJI
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• v.44 no.3
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• pp.232-236
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• 2000

An intravenous pharmacokinetics for a new red cell substitute, PEG-hemoglobin SB1, was studied in SD rats. Total-hemoglobin and its metabolite methemoglobin in the plasma were determined using a spectrophotometer. The limit of quantitation was 0.01g/dL and the C.V for interday assay reproducibility was less than 6%. Upon intravenous administration of anticipated clinical dose, 10 ml(0.7 gHb)/kg, plasma concentration curve of total-hemoglobin was well described by one-compartment model. The $t_{\frac{1}{2}},{\;}CL_{t}$, Vd and $AUC^{0-48hr}$ were $8.23{\pm}0.96{\;}hr,{\;}0.06{\;}{\pm}{\;}0.01 {\;}dL/hr/kg,{\;}0.66{\pm}0.05{\;}dL/lg{\;}and{\;}13.6{\;}{\pm}{\;}1.01g{\cdot}hr/dL$, respectively, in male rats(n=5, $mean{\;}{\pm}{\;}SD$). Those parameters in female rats were $9.21{\;}\pm{\;}2.31{\;}hr,{\;}0.06{\;}{\pm}{\;}0.01{\;}dL/hr/kg,{\;}0.79{\pm}{\;}0.08{\;}dL/kg{\;}and{\;}13.0{\;}{\pm}{\;}2.36{\;}g{\cdot}hr/dL$, respectively. Similar kinetic profiles between males and females were also obtained from other parameters. Small amount of methemoglobin, an oxidative metabolite of SB1, was detected in the plasma of both sexes, where the $AUC^{0-48{\;}hr,m}$ and $t_{{\frac{1}{2}},m}$ were approximately $1.5{\;}g{\cdot}hr/dL$ and 20 hr, respectively. The present work provides a critical kinetic data for the effective clinical applications of PEG-hemoglobin SB1.

• Journal of fish pathology
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• v.24 no.1
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• pp.29-37
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• 2011

Effects of temperature ($13{\pm}1.5^{\circ}C$, $23{\pm}1.5^{\circ}C$) on the pharmacokinetic properties of nalidixic acid (NA) and piromidic acid (PA) were studied after oral administration to cultured black rockfish, Sebastes schlegeli. Serum concentrations of NA and PA were determined using HPLC-UV detector after a single dosage of 60 mg/kg body weight. At $23{\pm}1.5^{\circ}C$, the peak serum concentrations of NA and PA, which attained at 24 h post-dose, were 5.87 and $0.43\;{\mu}g/ml$, respectively. At $13{\pm}1.5^{\circ}C$, the peak serum concentrations of NA and PA, which attained at 10 h post-dose, were 6.22 and $1.57\;{\mu}g/ml$, respectively. Better absorption of PA was noted at $13{\pm}1.5^{\circ}C$ compared to $23{\pm}1.5^{\circ}C$. However, absorption of NA was not affected significantly by temperature. The elimination of NA and PA from serum of black rockfish was considerably faster at $23{\pm}1.5^{\circ}C$ than at $13{\pm}1.5^{\circ}C$. The kinetic profile of absorption, distribution and elimination of NA and PA in serum were analyzed by fitting to a one compartment model, with WinNonlin program. The AUC, $T_{1/2}$, $T_{max}$ and $C_{max}$, respectively, were: $161.25\;{\mu}g{\cdot}h/ml$, 0.15 h, 12.29 h and $8.91\;{\mu}g/ml$ at $23{\pm}1.5^{\circ}C$, and $134.12{\mu}g{\cdot}h/ml$, 0.18 h, 8.79 h and $5.00\;{\mu}g/ml$ at $13{\pm}1.5^{\circ}C$ with NA; $41.57\;{\mu}g{\cdot}h/ml$, 0.58 h, 8.24 h and $0.21\;{\mu}g/ml$ at $23{\pm}1.5^{\circ}C$, and $40.36\;{\mu}g{\cdot}h/ml$, 0.59 h, 5.04 h and $1.20\;{\mu}g/ml$ at $13{\pm}1.5^{\circ}C$ with PA.

• Korean Journal of Clinical Pharmacy
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• v.9 no.1
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• pp.49-54
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• 1999

This study was carried out to compare the bioavailability of Hanmi clarithromycin (250 mg/tablet) with that of $Klaricid^{(R)}$ The bioavailability was examined on 20 volunteers who received a single dose (500 mg) of each drug in the fasting state in a randomized balanced 2-way crossover design. After dosing, blood samples were collected for a period of 12 hours. Plasma samples were analyzed for clarithromycin and roxithromycin(internal standard) by HPLC/Coulometric BCD. The pharmaco-kinetic parameters ($AUC_{0-l2hr}$, Cmax, Tmax, $AUC_{inf}$, Ka, Kel, $t_{1/2}$, Vd/F and Cl/F) were calculated from the plasma clarithromycin concentration-time data of each volunteer. The computer program 'WinNonlin' was used for compartmental analysis. One compartment model with first-order input, from order output with lag time, weighting factor $l/y^2$ was chosen as the appropriate pharmacokinetic model. The major pharmacokinetic parameters ($AUC_{0-l2hr},\;AUC_{inf}$, Cmax and Tmax) of Hanmi clarithromycin were $10.7\pm0.5\;{\mu}g{\cdot}hr{\cdot}ml^{-1},\;12.7\pm0.7\;{\mu}g{\cdot}hr{\cdot}ml^{-1},\;1.7\pm0.1\;{\mu}g/ml\;and\;2.0\pm0.2\;hr$, respectively, and those of $Klaricid^{(R)}\;were\;9.8\pm0.5\;{\mu}g{\cdot}hr{\cdot}ml^{-1},\;11.7\pm0.6\;{\mu}g{\cdot}hr{\cdot}ml^{-1},\;1.6\pm0.1\;{\mu}g/ml\;and\;2.1\pm0.1\;hr$, respectively. The differences in mean values of $AUC_{0-l2hr},\;AUC_{inf}$ and Cmax between two products were $9.88\%,\;8.94%\;and\;6.59\%$, respectively. The least significant differences at $\alpha=0.05$ for $AUC_{0-l2hr},\;AUC_{inf}$ and Cmax were $16.08\%,\;17.81\%\;and\;18.94\%$, respectively. Though the plasma clarithromycin concentrations of Hanmi clarithromycin were higher than those of $Klaricid^{(R)}$ at all observed times, the bioavailability of Hanmi clarithromycin appeared to be bioequivalent with that of $Klaricid^{(R)}$. The Ka, Kel, $t_{1/2}$, Vd/F and Cl/F of the Hanmi clarithromycin were $2.69\pm0.53\;hr^{-1},\;0.18\pm0.01 hr^{-1},\;3.9\;hr,\;248.8\pm11.4\;L\;and\;43.7\pm2.6\;L/hr$, respectively, and those of $Klaricid^{(R)} were 2.19\pm0.51\;hr^{-1},\;0.18\pm0.02\;hr^{-1},\;3.7\;hr,\;266.7\pm22.4\;L\;and\;45.3\pm2.8L/hr$, respectively. There were no statistically significant differences between two drugs in all pharmacokinetic parameters.

• Korean Journal of Veterinary Research
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• v.40 no.3
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• pp.471-478
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• 2000

The pharmacokinetic properties of KR-V compounds, recently developed as new anti-HIV agents, were studied after i.v. and p.o. administration in rats. The concentrations of the KR-V series were determined in rat plasma using an high-performance liquid chromatography (HPLC)-UV detection system. Of the 19 KR-V compounds investigated in the present study, only KR-V 3, 10, 14, 16 and 18-1 showed oral bioavailability. The plasma concentration-time data could be adequately described by an one-compartment open model. In the i.v. kinetic study (10mg/kg), the CLt of KR-V 3, 10, 14 and 16 (>4L/hr/kg) were significantly higher than that of KR-V 18-1 (1.1 L/hr/kg). The AUC of KR-V 18-1 was greater ($8.97{\mu}g{\cdot}hr/ml$) than that of the other compounds, but the Vd (0.58 L/kg) was lower. In the p.o. kinetic study (50mg/kg), although the t-1/2 of KR-V 18-1 was shorter than that of the other compounds, the AUC ($3.659{\mu}g{\cdot}hr/ml)$ and $C_{max}(1.891{\mu}g/ml$) were markedly higher. In a seperated in vitro experiment, only KR-V 18-1, of the 5 compounds with bioavailibility, exhibits potent activity against HIV-1 mutant strains. Therefore, KR-V 18-1 is expected to become a new potent anti-AIDS drug candidate/lead compound.