• Proceedings of the KSME Conference
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• 2003.04a
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• pp.648-653
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• 2003

In order to predict stress intensity limit of high-temperature creep structures, creep work-time equation, defined as $W_ct^P=B$, was used, and the results of the equation were compared with isochronous stress-strain curve (ISSC) ones of ASME BPV NH Code. For this purpose, the creep strain tests with. time variations for commercial type 316 stainless steel were conducted with different stresses; 160 MPa, 150 MPa, 145 MPa, 140 MPa and 135 MPa at $593^{\circ}C$. The results of log $W_c$ and log t plots showed a good linear relation up to $10^5$ hr. The constants p, B and stress intensity limit values showed comparatively good agreement to those of ASME NH ISSC. It is believed that the relation can be simply obtained with only several short-term 1% strain data without ISSC which can be obtained by long-term creep data.

• Journal of Korean Physical Therapy Science
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• v.15 no.1
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• pp.1-9
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• 2008

Background and Purpose : This study serves the purpose to present the effective way on back pain therapy for women during their pregnancy by comparing and analyzing the effects influencing on pain index, limits on daily life, and diminution of lumbar curve, when having treated for 6 weeks, dividing into therapy group, applied by decompression therapy on spine without unnecessary effects on the pregnant women and their fetus and the existent general physiotherapy group, applied on diminution of their back pain. Subject & methods : We made impregnate women of 30(25${\sim}$34years), as the subject of this study, who understood, and agreed with, this study, among pregnant women who were diagnosed as back pain. Pain intensity, limit index on daily life, and lumbar curve test, prior to experiment was implemented as paired t－test, comparison of the difference of average by each group before and after experiment was analysed as independent t－test, and statistical examination level was set up as 0.05. Results : The difference of average of pain and limit on daily life between the group, SDTG(spinal decompression therapy group), and the group, GPTG(general physical therapy group), before and after experiment was diminished as much as 44.4% and 16.79% each after completed 6 weeks' experiment, limit on daily life in both groups showed as much as 37.2% and 21.5% each, in the end, they statistically showed conspicuous difference(p<.05). Comparison of lumbar curves between both groups, SDTG and GPTG, before and after experiment, were diminished from -23.13${\pm}$4.85 to -15.66${\pm}$3.71, and there was no remarkable difference(p<.05). Conclusion : As, in this study, decompression therapy is more effective than general physical therapy with pregnancy low back pain in pain, limitation of daily life, lumbar curve.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.8 s.179
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• pp.2083-2090
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• 2000

In order to manage nuclear power plants safely and cost effectively, it is necessary to develop integrity evaluation methodologies for the main components. Recently, the integrity evaluation techniques were broadly studied regarding the license renewal of nuclear power plants which were approaching their design lives. Since the integrity evaluation process requires special knowledges and complicated calculation procedures, it has been allowed only to experts in the specified area. In this paper, an integrity evaluation system for reactor pressure vessel was developed. RVIES(Reactor Vessel Integrity Evaluation System) provides four specific integrity evaluation procedures covering PTS(Pressurized Thermal Shock) analysis, P-T(Pressure-Temperature) limit curve generation, USE(Upper Shelf Energy) analysis and Fatigue analysis. Each module was verified by comparing with published results.

• Nuclear Engineering and Technology
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• v.54 no.6
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• pp.2188-2197
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• 2022

To ensure the safety margin of a reactor pressure vessel (RPV) under normal operating conditions, it is regulated through the pressure-temperature (P-T) limit curve. The stress intensity factor (SIF) obtained by the internal pressure and thermal load should be obtained through crack analysis of the nozzle corner crack in advance to generate the P-T limit curve for the nozzle. In the ASME code Section XI, Appendix G, the SIF via the internal pressure for the nozzle corner crack is expressed as a function of the cooling or heating rate, and the wall thickness, however, the SIF via the thermal load is presented as a polynomial format based on the stress linearization analysis results. Inevitably, the SIF can only be obtained through finite element (FE) analysis. In this paper, simple prediction equations of the SIF via the thermal load under, cool-down and heat-up conditions are presented. For the Korean standard nuclear power plant, three geometric variables were set and 72 cases of RPV models were made, and then the heat transfer analysis and thermal stress analysis were performed sequentially. Based on the FE results, simple engineering solutions predicting the value of thermal SIF under cool-down and heat-up conditions are suggested.

• Archives of Pharmacal Research
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• v.11 no.3
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• pp.250-252
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• 1988

A sensitive and simplified HPLC assay of fluconazol is described. The calibration curve of fluconazol in plasma ranging $0-10\;{\mu}g/ml$ was linear with the correlation coefficients of 0.9900. The limit of detection was $0.3\;{\mu}g/ml$. The average recovery of the drug was $89.1\;{\pm}\;9.05%$. After oral administration of single dose(150mg) of fluconazol in man, $C_{max}\;and\;T_{max$ were $3\;{mu}g/ml$ and 4hr., respectively.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.4
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• pp.350-357
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• 2019

Purpose: This study aimed to evaluate a possible association between the anti-tissue transglutaminase antibody (anti-tTG) titer and stage of duodenal mucosal damage and assess a possible cut-off value of anti-tTG at which celiac disease (CD) may be diagnosed in children in conjunction with clinical judgment. Methods: This observational study was conducted at a gastroenterology clinic in a tertiary hospital from April 2012 to May 2013. Seventy children between 6-months and 18-years-old with suspected CD underwent celiac serology and duodenal biopsy. Statistical analyses were done using SPSS 16. Diagnostic test values were determined for comparing the anti-tTG titer with duodenal biopsy. An analysis of variance and Tukey-Kramer tests were performed for comparing the means between groups. A receiver operating characteristics curve was plotted to determine various cut-off values of anti-tTG. Results: The mean antibody titer increased with severity of Marsh staging (p<0.001). An immunoglobulin (Ig) A-tTG value at 115 AU/mL had 76% sensitivity and 100% specificity with a 100% positive predictive value (PPV) and 17% negative predictive value (NPV) for diagnosis of CD (p<0.001, 95% confidence interval [CI], 0.75-1). Conclusion: There is an association between the anti-tTG titer and stage of duodenal mucosal injury in children with CD. An anti-tTG value of 115 AU/mL (6.4 times the upper normal limit) had 76% sensitivity, 100% specificity, with a 100% PPV, and 17% NPV for diagnosing CD (95% CI, 0.75-1). This cut-off may be used in combination with clinical judgment to diagnose CD.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.117-117
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• 1997

Sandimmune Neoral$\^$(R)/ and Neoplanta$\^$(R)/ capsules were administered to twenty four healthy Korean male subjects at a cyclosporin A (CsA) dose of 175 mg in a 2 ${\times}$ 2 crossover investigation with a two-week wash-out phase. Concentrations of CsA in blood were measured by RIA method for over a period of 48 h. Result : The two formulations were found bioequivalent, but analysis of variance (ANOVA) indicated that there is a significant (p<0.01) period effect in AUC$\_$0-LAST/ (area under the blood concentration above assay limit of quantification-time curve) and C$\_$MAX/ (maximum blood concentration) between the administrations. Paired t-test revealed 6 and 9% decreases in AUC$\_$0-LAST/ and C$\_$MAX/, respectively at the second administration. This period effect on the pharmacokinetics of CsA may be relevant for the patients who need consecutive administration of the drug. A number of mechanisms, such as induction of the enzymes responsible for metabolism of the drug in the gut wall and/or liver and modulation of P-glycoprotein upon the consecutive dosing, appear consistent with the change, and needs experimental proof.

• Journal of the Korean Ceramic Society
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• v.22 no.3
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• pp.35-40
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• 1985

The composition of the base glass was determined to be $Na_2O$ 15, $Fe_2O_3$ 35, $B_2O_3$ 0~20, $P_2O_5$ 30~50 by mole percent. The heating temperature for nucleation was determined by means of thermal expansion curve. Crystalline phases were investigated by X-ray diffraction method and I.R Spectra. Electrical conductivities of glass spec-imens were observed in the temperature range 25~20$0^{\circ}C$ The activation energies of these specimens were caculated. The results obtained were as follows : 1) The limit composition of the melts 15mol% $Na_2O$ 35mole% $Fe_2O_5$ 20mole% $B_2O_3$ 30mole% $P_2O_5$ was able to be formed into desired shapes during cooling, . 2) In the measurement of d. c conductivity($\delta$) on the glasses in the system $15Na_2O-35Fe_2O_3$-$B_2O_3$-(50-x) $P_2O_5$ the values decreased by replacing 5 mole% $P_2O_5$ with $B_2O_3$ 3) The d. c conducties of heat treated samples were increased by replacing $P_2O_5$ with $B_2O_3$ 4) $B_2O_3$ contributed to precipitate crystals such as${\gamma}$-$Fe_2O_3$ $Fe_3O_4$ which had the advantage of electronic conduction in heat treated samples. 5) The slope plotted Log($\delta$) versus 1/T in this glass system was linear in the measured temperature range.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.6
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• pp.864-873
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• 2013

In developing countries, biogas energy production is seen as a technology that can provide clean energy in poor regions and reduce pollution caused by animal manure. Laboratories in these countries have little access to advanced gas measuring equipment, which may limit research aimed at improving local adapted biogas production. They may also be unable to produce valid estimates of an international standard that can be used for articles published in international peer-reviewed science journals. This study tested and validated methods for measuring total biogas and methane ($CH_4$) production using batch fermentation and for characterizing the biomass. The biochemical methane potential (BMP) ($CH_4$ NL $kg^{-1}$ VS) of pig manure, cow manure and cellulose determined with the Moller and VDI methods was not significantly different in this test (p>0.05). The biodegradability using a ratio of BMP and theoretical BMP (TBMP) was slightly higher using the Hansen method, but differences were not significant. Degradation rate assessed by methane formation rate showed wide variation within the batch method tested. The first-order kinetics constant k for the cumulative methane production curve was highest when two animal manures were fermented using the VDI 4630 method, indicating that this method was able to reach steady conditions in a shorter time, reducing fermentation duration. In precision tests, the repeatability of the relative standard deviation (RSDr) for all batch methods was very low (4.8 to 8.1%), while the reproducibility of the relative standard deviation (RSDR) varied widely, from 7.3 to 19.8%. In determination of biomethane concentration, the values obtained using the liquid replacement method (LRM) were comparable to those obtained using gas chromatography (GC). This indicates that the LRM method could be used to determine biomethane concentration in biogas in laboratories with limited access to GC.

• Archives of Pharmacal Research
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• v.29 no.6
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• pp.514-519
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• 2006

A simple HPLC method using UV detection was developed and validated for the determination of levodropropizine (LDP) In dog plasma. The sample was prepared for injection using a liquid-liquid extraction method with 1-phenypiperazine as the internal standard. The mobile phase was methanol - diethylamine solution (0.05 M) (20:80, v/v, pH adjusted to 3.0 with $H_3PO_4$) with a detection wavelength of 240 nm. The limit of quantitation (LOQ) of LDP in a biological matrix was determined to be 25.25 ng/mL. The calibration curve was linear across the concentration range of 25.25 to 2020 ng/mL. The intra-day and inter-day precision values (CV%) were within 7% and accuracy (R.E. %) was within 6% of the nominal values for medium (252.5 ng/mL) and high (2020 ng/mL) LDP concentrations. For the LDP concentration at the LOQ, the intra-day and inter-day precision and accuracy were within 20% and 10%, respectively. The average absolute recovery for LDP was 70.28%. This method was successfully used to analyze plasma samples in a steady-state bioavailability study of a newly developed sustained-release LDP tablets (SR) using immediate-release tablets (IR) as the reference. The relative bioavailability of the SR was determined to be $106.3\;{\pm}\;12.8%$ (n=6). The $C_{max}$ of the SR was significantly lower (p<0.05), and the $t_{max}$ was significantly longer than that of the IR (p<0.05). The results of ANOVA and two one-sided tests indicated that the SR exhibited acceptable sustained release properties and was bioequivalent to the IR.