• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5D
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• pp.877-884
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• 2006

GPS is an essential tool for applications that be required high positioning precision, for the velocity field estimation of tectonic plates. The three years data of eight GPS permanent station were analyzed to estimate crustal deformation velocities using Gipsy-oasis II software. The velocity vectors of GPS stations are estimated by linear regression method in daily solution time series. The velocities have a standard deviation of less than 0.1mm/yr and the magnitude of velocities given by the Korean GPS permanent stations were very small, ranging from 25.1 to 31.1 mm/yr. The comparison between the final solution and other sources, such as IGS velocity result calculated from SOPAC was accomplished and the results generally show good agreement for magnitude and direction in crustal motion. To evaluate the accuracy of our results, the velocities obtained from six plate motion model was compared with the final solution based on GPS observation.

• Animal Systematics, Evolution and Diversity
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• v.5 no.1
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• pp.77-88
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• 1989

Genetic and morphometric comparison between two species of the genus Agkistrodon were performed to estimate the degree of genic variation and to clarify the taxonomic status of Cheju population, a suspected hybrid form between A. blomhoffii brevicaudus and A u ussuriensis. A sum of 147 specimens representing six populations of A.b. brevicaudus and two populations of A ussuriensis was used in this study. Out of the 21 loci examined, 5 loci (Adh, Ldh-2, Mdh-2, Mpi, Pgi) were monomorphic with identical mobility in both species. O Other Sioci (Aco, Gp, Fum, [po and Xdh in A b. brevicaudus; Est, Got-l, Gp, Mdh-l and 6Pgd in A ussuriensis) were highly poplymorphic. The degree of genic variation of Ab. b brevicaudus and A ussuriensis was A=1.SS, P=42.1%, HD=0.096, HG=O.l1S, and A= 1.4S, P = 31.6%, HD=0.117, HG =0.121, repectively. These values are twofold higher t than those of other reptilian species reported (Selander, 1976) including Korean species of Rhabdophis tigrina and Elaphe dione (Paik and Yang, 1986, 1987). The average values of t the genetic similarities among six populations of A b. brevicaudus and two populations of A ussuriensis were S=0.919 and S=0.962, respectively, whereas the value between species was S = 0.662. Presumed divergent time estimate (Nei, 1975) of these two species was about 1 1.8 million years ago. The analysis of the geographic variations of various morphological c characters was based on Gloyd’s criteria (Gloyd, 1972). Coloration of tongue and tail tip, t the number of ventral scales, and the number of subcaudal scales are good diagnostic c characters to identify these two species. The pattern of cross band is, however, highly variable within and between populations of both species. No hybrid was detected and the s suspected hybrid form of Cheju population falls within the range of A. ussuriensis in the g genetic and morphometric analyses.

• Journal of the Korean Geophysical Society
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• v.6 no.4
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• pp.269-276
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• 2003

Sub-bottom profile were conducted in Chungju Regulation Lake by use of ground penetrating radar(GPR). The survey area covers approximately 1,000,000 $m^2$ and total survey line length is about 5km and more. GPR surveys with GPS system were made across and transverse direction of the lake. From the survey results of GPR, it could be possible to distinguish the gravel and/or sand dominant bed from silt and/or clay material dominant bed.

• Restorative Dentistry and Endodontics
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• v.34 no.6
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• pp.484-490
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• 2009

The purpose of this study was to evaluate the effect of soft chelating irrigant on the sealing ability of root fillings by using a glucose leakage test. A total of 45 single-rooted teeth were selected for the study. The teeth were decoronated leaving a total length of 13mm. The root canals prepared using K3 NiTi rotary instruments to an apical dimension of size 45(0.06 taper). The specimens were then randomly divided into 3 experimental groups of 13 roots each and 2 control groups of 3 roots each. Specimen in each group were prepared with different irrigation protocols : group 1, 2.5% NaOCl; group 2, 2.5% NaOCl and 17% EDTA: group 3, 2.5% NaOCl and 15% HEBP. The root canals were filled with gutta-percha and AH Plus sealer using lateral condensation. After 7 days in $37^{\circ}C$, 100% humidity, the coronal-to-apical microleakage was evaluated quantitatively using a glucose leakage model. The leaked glucose concentration was measured with spectrophotometry at 1, 4, 7, 14, 21 and 28 days. There was a tendency of increase in leakage in all experimental groups during experimental period. HEBP-treated dentin showed no significant difference with EDTA-treated dentin during experimental period. From the 21th day onward, HEBP-treated dentin showed significantly lower leakage than smear-covered dentin. HEBP-treated dentin displayed a similar sealing pattern to EDTA-treated dentin and a better sealing ability than smear-covered dentin. Consequently, a soft chelator(HEBP) could be considered as the possible alternative to EDTA.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.2
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• pp.153-157
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• 2000

Hydrolysate which inhibit the Angiotensin I-converting enzyme (ACE) was prepared from mackerel muscle by pretense. The ACE inhibitory activity of mackerel muscle hvdrolysate (MMH) was $967 {\mu}g of IC_(50)$. ACE inhibitory peptides were isolated by ultrafiltration, gel permeation column chromatography (GPC), reversed phase column chromatography(RPC), reversed phasehigh performance liquid chromatography (RP-HPLC), and gel permeation high performance liquid chromatography (GP-HPLC) from the MMH. The amino acid sequence of the ACE inhibitory peptides was Tyr-Val-Ala. The $IC_(50)$ of this peptide for ACE from rabbit lung was $1.4 {\mu}M$.

• Journal of Digital Convergence
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• v.17 no.10
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• pp.461-468
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• 2019

The aim of this study was to compare and analyse the national players between the winning games and the losing ones by classifying the GPS data measured in the competition. 27 players of Korean national team on field hockey had analysed to collect plenty of data by using GPS system in real time on 16 A-matches for this paper. The result was followed: First, it has revealed that the winning games showed that it had played a lot in the rest of the zone except for zone 1 and zone 5 from zone 1 to zone 6. Second, is has also shown that it had a significant differences into the distance between the winning games and the losing ones. Third, there were no significant differences between Low-speed zone (zone 1 to Zone 3) and High-speed zone (zone 4 to zone 6) into the distance but were a significant differences on the number of high-accelerations in a section of accelerations. Last, in the position-specific, it has shown a significant differences between a distance by the section and the acceleration frequency and the results showed that the difference between the low accelerations and high ones influenced positively related to the performance.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.5
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• pp.684-693
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• 2005

Statement of problem: Ti-6Al-7Nb alloy is used instead of Ti-6Al-4V alloy that was known to have toxicity. Purpose: This study was performed to investigate the effect of electrolyte concentration on the surface characteristics of anodized and hydrothermally-treated Ti-6Al-7Nb alloy Materials and methods: Discs of Ti-6Al-7Nb alloy of 20 mm in diameter and 2 mm in thickness were polished sequentially from #300 to 1,000 SiC paper ultrasonically washed with acetone and distilled water for 5 min, and dried in an oven at $50^{\circ}C$ for 24 hours. Anodizing was performed at current density $30mA/cm^2$ up to 300 V in electrolyte solutions containing $\beta-glycerophosphate$ disodium salt hydrate $(\beta-GP)$ and calcium acetate (CA). Hydrothermal treatment was conducted by high pressure steam at $300^{\circ}C$ for 2 hours using a autoclave. All samples were soaked in the Hanks' solution with pH 7.4 at $36.5^{\circ}C$ for 30 days. Results and conclusion: The results obtained were summarized as follows: 1. After hydrothermal treatment, the precipitated HA crystals showed the dense fine needle shape. However, with increasing the concentration of electrolyte they showed the shape of thick and short rod. 2. When the dense fine needle shape crystals was appeared after hydrothermal treatment, the precipitation of HA crystals in Hanks' solution was highly accelerated. 3. The crystal structures of $TiO_2$ in anodic oxide film were composed of strong anatase peak and weak rutile peak as analyzed with thin-film X-ray diffractometery. 4. The Ca/P ratio of the precipitated HA layer was equivalent to that of HA crystal in Hanks' solution.

• Journal of Advanced Navigation Technology
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• v.17 no.6
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• pp.600-608
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• 2013

The great Tohoku-oki earthquake which occurred on March 11, 2011, caused crustal movements in both Korea and Japan. This study attempts to analyze velocity changes of crustal movement of Korea Peninsula due to the Tohoku-oki earthquake and to compare the calculation with precious crustal movenents of Korea Peninsula. We found that the crustal movement velocity of South Korea increased 3.9 mm/yr northward and 7.5 mm/yr eastward on average as a result of the Tohoku-oki earthquake; when this figure is compared with the past crustal movement velocities of the Korea Peninsula.

• Journal of the Korean Society for Heat Treatment
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• v.10 no.4
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• pp.237-245
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• 1997

A study was conducted to examine the effects of In addition on the precipitation behaviors of Al-2.1Li-2.9Cu alloy by differential scanning calorimetry, transmission electron microscopy and micro-hardness tester. DSC analysis was measured over the temperature range of $25{\sim}550^{\circ}C$ at a heating rate of $2{\sim}20^{\circ}C$/min. The heat evolution peaks due to the formation of GP zone and ${\delta}$'phase shift to higher temperature and the peaks to $T_1$ and ${\theta}$'phases shift to lower temperature by In addition. From this result, it was proved that the formation of GP zone and ${\delta}$'phase is suppresed whereas that of $T_1$ and ${\theta}$'phases are accelerated by the In addition of 0.15wt%. The age hardening curve aged at $190^{\circ}C$ showed that the In bearing alloy(alloy B) has more faster age hardening response and a higher peak hardness than In-free alloy(alloy A), attributed to the fine and homogeneous distribution of $T_1$ and ${\theta}$'phases. The activation energies for the formation of ${\delta}$'phase in In-free and In-bearing alloys are 22.3kcal/mol and 18.6kcal/mol, respectively. Those for $T_1(+{\theta}^{\prime})$ phase of In-free and In-bearing alloys are 24.3 and 37.5kcal/mol, respectively. Quenched-in excess vacancies play an important role to the formation of precipitates.

• Korean Journal of Clinical Pharmacy
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• v.20 no.1
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• pp.25-29
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• 2010

The purpose of this study was to investigate the effect of atorvastatin on the pharmacokinetics of nifedipine (6 mg/kg) after oral administration of nifedipine with or without atorvastatin (0.5 and 2.0 mg/kg) in rats, and also was to evaluate to the effect of atorvastatin on the CYP3A4 activity. The 50% inhibiting concentration ($IC_{50}$) values of atorvastatin on CYP3A4 activity is 46.1 ${\mu}M$. Atorvastatin inhibited CYP3A4 enzyme activity in a concentration-dependent manner. Coadministration of atorvastatin increased significantly (p<0.05, 2.0 mg/kg) the plasma concentration-time curve (AUC) and the peak concentration ($C_{max}$) of nifedipine compared to the control group. The relative bioavailability (RB%) of nifedipine was increased from 1.15- to 1.37-fold. Coadministration of atorvastatin did not significantly change the terminal half-life ($T_{1/2}$) and the time to reach the peak concentration ($T_{max}$) of nifedipine. Based on these results, we can make a conclusion that the significant changes of these pharmacokinetic parameters might be due to atorvastatin, which possesses the potency to inhibit the metabolizing enzyme (CYP3A4) in the liver and intestinal mucosa, and also inhibit the P-glycoprotein (P-gp) efflux pump in the intestinal mucosa. It might be suggested that atorvastatin altered disposition of nifedipine by inhibition of both the first-pass metabolism and P-glycoprotein efflux pump in the small intestine of rats. In conclusion, the presence of atorvastatin significantly enhanced the oral bioavailability of nifedipine, suggesting that concurrent use of atorvastatin with nifedipine should require close monitoring for potential drug interation.