• Korean Journal of Applied Biomechanics
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• v.23 no.1
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• pp.11-17
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• 2013

The purpose of this study was to provide a fundamental information for enhancing 110m hurdlers' performance through conducting comparative biomechanical analysis between Skilled Group(SG) and Less-Skilled Group(LSG) those who are not in the first section of 110m hurdles. To persue the purpose of this study, total of 10 hurdlers participated. Then they were divided into two groups; SG: five hurdlers who have won awards with 14-second range at 2010 national track and field event, and LSG: five hudlers who did not win any awards with 15-second range. Three-dimensional motion analysis with 12 infrared cameras(Oqus 300, Qualisys) and 1 force plate(Type 9286AA, Kistler) was performed. From this study following conclusions were obtained. 1) For the overall runtime, SG revealed faster elapsed time than that of LSG. 2) At E4, LSG showed greater trunk angle than that of SG. 3) At E3 LSG revealed higher angular velocities than that of SG. 4) No significant differences was found for AP GRF between groups but LSG showed greater VGRF than that of SG.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.16 no.1
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• pp.119-132
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• 1998

For the purpose of producing of grid D.E.M based on National Digital Map accurately and efficiently, We must carefully consider arrangement and numbers of it's elevation information, supplement interpolation method of control point information for maintaining accuracy. According to each combination, each of them has an effect on estimate elevations. This study, after finishing experimental analysis of several grid distance and interpolation methods, aims at presenting the optimal grid distance and interpolation method in the production of grid D.E.M by using of National Digital Map. The results are as follows: First, The result of experimental analysis shows that the method of Kriging is a very excellent interpolation method in the production of grid D.E. M by using National Digital Map. Second, For the purpose of determining grid distance, this study present that twice of the amount of contour interval to make producing grid D.E.M is optimal distance.

• Nuclear Engineering and Technology
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• v.49 no.4
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• pp.838-849
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• 2017

This paper proposes penalty factor equations that take into consideration the weld strength over-match given in the classified form similar to the revised equations presented in the Code Case N-779 via cyclic elastic-plastic finite element analysis. It was found that the $K_e$ analysis data reflecting elastic follow-up can be consolidated by normalizing the primary-plus-secondary stress intensity ranges excluding the nonlinear thermal stress intensity component, $S_n$ to over-match degree of yield strength, $M_F$. For the effect of over-match on $K_n{\times}K_{\nu}$, dispersion of the $K_n{\times}K_{\nu}$ analysis data can be sharply reduced by dividing total stress intensity range, excluding local thermal stresses, $S_{p-lt}$ by $M_F$. Finally, the proposed equations were applied to the weld between the safe end and the piping of a pressurizer surge nozzle in pressurized water reactors in order to calculate a cumulative usage factor. The cumulative usage factor was then compared with those derived by the previous $K_e$ factor equations. The result shows that application of the proposed equations can significantly reduce conservatism of fatigue assessment using the previous $K_e$ factor equations.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.8
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• pp.876-883
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• 2007

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.53-57
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• 1989

Until now, method of equivalent circuit is generally used in analyzing the characteristic of the synchronous alternator. But this method can't apply when loads are connected to alternator. In this paper, we analyzed the load characteristic of the synchronous alternator with permanant magnet using 2-dimensional finite element method having voltage source. The loads of a alternator are battary and diodes which are used to rectify. also, we used half periodic boundary condition in the F.E.M calculation

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.7
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• pp.331-338
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• 2002

An inverter-fed induction is driven by a harmonic voltage source so that it is necessary to be analysed by time-stepping F.E.M. But it takes so long time that disadvantageous to design. This paper presents a simple analysis method for inverter-fed induction motor using FEM and harmonic equivalent circuit. First, the rotor bar resistance and the leakage reactance are determinated by FEA for 1 slot region in rotor to consider the skin effect and the saturation. Secondly, the characteristic of the motor is analyzed by the harmonic equivalent circuits consisting of the obtained parameters from the FEA. This method is carried out to analyze an induction motor driven by the sinusoidal voltage and the inverter. The results are verified by comparing with those of the time-step F.E.A and the experiment.

• Journal of the Korean Chemical Society
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• v.38 no.2
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• pp.160-168
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• 1994

Pentadentate Schiff base molybdenum(Ⅴ) complexes such as [Mo(Ⅴ)O(Sal-DET)(NCS)] and [Mo(Ⅴ)O(Sal-DPT)(NCS)] were synthesized by Sabat method. The structure of these complexes were identified by elemental analysis, spectroscopy, and thermogravimetric analysis(T.G.A.). It was found that the mole ratio of Schiff base ligand to the complexes was found to be 1 : 1. The redox processes of the complexes were investigated by cyclic voltammetric and differential pulse polarographic technique in nonaqueous solvent containing 0. 1 M tetraethyl ammonium perchlorate(TEAP) as supporting electrolyte at glassy carbon electrode. It was found that diffusion controlled reduction processes of four steps with one electron were 2Mo(Ⅴ)$\rightleftarrow^{e-}$ Mo(Ⅴ)Mo(Ⅳ) $\longrightarrow^{e-}$ 2Mo(Ⅳ), Mo(Ⅳ) $\longrightarrow^{e-}$ Mo(Ⅲ) $\longrightarrow^{e-}$ Mo(Ⅱ)

• Journal of Ginseng Research
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• v.35 no.4
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• pp.421-428
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• 2011

This study evaluated cholineresterase inhibitory activity of Korean white ginseng extract (WGE), red ginseng extract (RGE), and black ginseng extract (BGE) and the cholinergic effect on scopolamine (SCOP)-induced amnesic mice. WGE, RGE, and BGE inhibited acetylcholineserase (AChE), as well as butyrylcholineserase (BuChE) in a concentration-dependent manner. BGE presented strong inhibition of AChE with an $IC_{50}$ value of 1.72 mg/mL, followed by WGE (5.89 mg/mL), RGE (6.30 mg/mL), respectively. The inhibitory activity of the three ginseng extracts on BuChE showed similar values among the groups. To better understand the mechanisms of the possible effect of ginseng extract on the cholinergic function, this study assessed the expression of the cholinergic markers of choline acetyltransferase (ChAT) and AChE using western blot and RT-PCR analysis in the brains of amnesic mice. Treatment with ginseng extracts led to inhibition of AChE expression and, the activation of ChAT expression in the hippocampus and the cerebral cortex of amnesic mice as induced by SCOP. The results suggest that ginseng extracts including BGE, appear to modulate the metabolism of acetylchoine (ACh), which would greatly increase synaptic ACh levels and most potently revert SCOP-induced amnesia.

• Proceedings of the PSK Conference
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• 2001.04a
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• pp.220.3-221
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• 2001

• Journal of Aquaculture
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• v.13 no.1
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• pp.79-85
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• 2000

The effects of estrogen and androgens on Vg gene expression were examined in primary hepatocyte culture and livers of the immature male trout. Specific primers of Vg cDNA were designed with already reported Vg gene nucleotide sequences. PCR product was sequenced and verified with Vg cDNA of rainbow trout. Total RNA was extracted from the cultured hepatocytes and livers of steroid-treated rainbow trout and then it was analyzed by reverse transcriptase- polymerase chain reaction (RT-PCR) analysis. The Vg mRNA and Vg protein synthesis were increased in rainbow trout in vivo and in vitro with E$_2$ and methyltestosterone (MT) There were dose and time-related effects of E$_2$ and MT on vitellogesis. Androgens such as progesterone androsterone and testosterone also stimulated Vg mRNA expression in vitro. The results show that androgens as well as E$_2$ can induce expression of Vg mRNA in trout in vivo and in vitro.