• Journal of the Korean Chemical Society
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• v.43 no.4
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• pp.430-437
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• 1999

The determination of total chlorine residuals in drinking water by flow injection analysis(FIA) with iodometric UV detection was investigated. The pH of the acid stream, the concentration of the iodide ion,the length of the mixing and reaction coils, the injection sample size, and flowrate were optimized as parameters for determining total chlorine residuals by FIA method. lodide was selectively oxidized to iodine by hypochlorite at pH 8.3 Ethylenediamine as masking agent for masking interference ions from the sample was given the best efficency. Calibration curve presented linear range of 0.03-3 mg/L for hypochlorite ion with a correlation coefficient of 0.999 or better. The detection limit was found to be 0.007 mg/L for hypochlorite ion. Under these analytical conditions, total chlorine residuals in several tap water sampled in the city of Jeonju were analyzed.

• Korean Journal of Clinical Pharmacy
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• v.9 no.2
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• pp.88-91
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• 1999

The purpose of this study was to compare the pkarmacokinetic parameters of vancomycin using a 2-compartment model in 8 Korean healthy volunteers and 8 lymphoma patients. Vancomycin (1.0 g) was administered by IV infusion over 60 minutes. The $\beta-phase$ rate constant $(\beta)$, apparent volume of distribution at steady srate $(V_{ss})$, total body clearance (CL) and area under the plasma level-time curve (AUC) of vancomycin in healthy volunteers were $0.15\pm0.02\;hr^{-1},\;33.8\pm4.12\;L/kg,\;5.36\pm0.61\;L/hr\;and\;185.8\pm20.5\;{\mu}g/ml{\cdot}hr$, respectively. The corresponding values in lymphoma patients ere $0.09\pm0.02\;hr^{-1},\;38.2\pm5.11\;L/kg,\;4.58\pm0.52\;L/hr\;and\;218.3\pm22.9\;{\mu}g/ml{\cdot}hr$. There were significant differences (p<0.05) in ${\beta}$ and CL between healthy volunteers and lymphoma patients.

• Journal of Ocean Engineering and Technology
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• v.22 no.3
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• pp.96-102
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• 2008

As LNG tank is operated around $-162^{\circ}C$, an experimental approach on the cryogenic temperature tensile and fatigue strengths of SUS304L lap joint weld is very important at the design stage of membrane type LNG tank. In this study, in order to estimate the tensile and fatigue strengths of SUS304L lap joint weld at cryogenic temperature condition, tensile and fatigue tests were conducted. Also, S-N curves are presented with statistical testing method recommended by JSME. As a result of the experimental approach, the d￡sign guide of fatigue strength is proposed and that is expected to be useful for membrane type LNG tank design.

• Bulletin of the Korean Chemical Society
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• v.25 no.1
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• pp.115-118
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• 2004

We have examined the feasibility of using the specific interaction between mistletoe lectin I (ML I) and ${\beta}$-Dgalactose instead of the anti-ML I antibody in developing a homogeneous type competitive binding assay for ML I. We also have examined the feasibility of adapting the biotin/avidin mediated homogeneous assay for this system. Alkaline phosphatase (AKP) was employed as a single substrate enzyme label. The dose-response curve shows a detection range of 1-25 ${\mu}$g/mL and a linear response with a correlation coefficient of 0.99. To demonstrate the analytical utility of this method, 10 ${\mu}$g/mL of ML I was spiked into distilled water. The results show that the mean recovery was 10.03 ${\mu}$g/mL with an SD of 0.18. The difference between the spiked value and the mean recovery was 0.03 ${\mu}$g/mL, with a relative error of 0.3 and 1.6 % of RSD.

• Journal of Astronomy and Space Sciences
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• v.36 no.2
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• pp.75-86
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• 2019

UV Psc is a typical RS CVn type system undergoing dynamic chromosphere activity. We performed photometric observations of the system in 2015 and secured new BVR light curves showing well-defined photometric waves. In this paper, we analyzed the light curves using Wilson-Devinney binary code and investigated the orbital period of the system. The combination of our light curve synthesis with the spectroscopic solution developed by previous investigators yielded the absolute parameters as: $M_1=1.104{\pm}0.042M_{\odot}$, $R_1=1.165{\pm}0.025R_{\odot}$, and $L_1=1.361{\pm} 0.041L_{\odot}$ for the primary star, and $M_2=0.809{\pm}0.082M_{\odot}$, $R_2=0.858{\pm}0.018R_{\odot}$, and $L_2=0.339 {\pm}0.010L_{\odot}$ for the secondary star. The eclipse timing diagram for accurate CCD and photoelectric timings showed that the orbital period may vary either in a downward parabolic manner or a quasi-sinusoidal pattern. If the latter is adopted as a probable pattern for the period change, a more plausible account for the cyclic variation may be the light time effect caused by a circumbinary object rather than an Applegate-mechanism occurring via variable surface magnetic field strengths.

• Analytical Science and Technology
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• v.35 no.5
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• pp.218-227
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• 2022

A simple and fast throughput flow injection (FI) system with a merging-zone technique was designed to determine ferrous and ferric in an aqueous solution. The method is based on the direct reaction of ferrous with a Bathophenanthroline reagent (Bphen) in acidic media. The forming red complex absorbs light at 533 nm. All conditions of the flow injection system were investigated. The analytical curve of ferrous was linear in the range of 0.07 to 4 mg/L with an r² value of 0.9968. The detection and quantification limits were 0.02 and 0.04 mg/L, respectively. The molar absorptivity and Sandell's sensitivity were 4.0577 × 10⁶ L/mol cm and 25 × 10^-5 ㎍/cm², respectively. The homemade valve was low-cost with high repeatability (n = 7) at an RSD of 1.26 % and zero dead volume. The values of the dispersion coefficient were 2.318, 2.022, and 1.636 for the concentrations of 0.2, 1, and 3 mg/L, respectively. The analysis throughput of the designed flow injection unit was 57 sample per hour.

• Mass Spectrometry Letters
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• v.13 no.1
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• pp.20-25
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• 2022

Fargesin, a tetrahydrofurofuranoid lignan isolated from Flos Magnoliae, shows anti-inflammatory, anti-oxidative, anti-allergic, and anti-hypertensive activities. To evaluate the pharmacokinetics of fargesin in mice, a sensitive, simple, and selective liquid chromatography-high resolution mass spectrometric method using electrospray ionization and parallel reaction monitoring mode was developed and validated for the quantification of fargesin in mouse plasma. Protein precipitation of 6 µL mouse plasma with methanol was used as sample clean-up procedure. The standard curve was linear over the range of 0.2-500 ng/mL in mouse plasma with the lower limit of quantification level at 0.2 ng/mL. The intra- and inter-day coefficient variations and accuracies for fargesin at four quality control concentrations including were 3.6-11.3% and 90.0-106.6%, respectively. Intravenously injected fargesin disappeared rapidly from the plasma with high clearance values (53.2-55.5 mL/min/kg) at 1, 2, and 4 mg/kg doses. Absolute bioavailability of fargesin was 4.1-9.6% after oral administration of fargesin at doses of 1, 2, and 4 mg/kg to mice.

• Journal of Practical Agriculture & Fisheries Research
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• v.16 no.1
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• pp.25-35
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• 2014

Tremella fuciformis produces white jelly fruitbody which is used as a special food in the orient. Symbiotic relationship between T. fuciformis and Hypoxylon sp. is important for mass production of fruitbody in T. fuciformis. T. fuciformis showed the peak of 24mg/2mL on the 9th day, after that mycelial growth maintained a gentle curve. Protein content increased into 0.69㎍/mL in rapid, T. fuciformis fruiting body maintained high galactose, mycelia of T. fuciformis showed 42.6% trehalose.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.388-391
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• 2004

A sol-gel fiber-optic biosensor with encapsulated pH-sensitive fluorophore and immobilized genetically modified toluene-o-xylene monooxygenase was developed to detect TCE and PCE, which are carcinogenic chlorinate organic compounds prevailing in ground water. The sensitivity was characterized for the composition of sol-gel, and manufacturing procedure. The intensity curve reveals a linear range of intensity for pollutant concentration range of 0.01ppm and 1ppm. The change in intensity was appeared to be larger at each of L for same condition, and, therefore, the wavelength of λ was chosen for the analytical measurement.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2004.10a
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• pp.313-316
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• 2004

Model selection is the process that sets up the regularization parameter in the support vector machine or regularization network by using the external methods such as general cross validation or L-curve criterion. This paper suggests that the regularization parameter can be obtained simultaneously within the learning process of neural networks without resort to separate selection methods. In this paper, extended kernel method is introduced. The relationship between regularization parameter and the bias term in the extended kernel is established. Experimental results show the effectiveness of the new model selection method.