• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.457-460
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• 2014

Precession coefficient is defined by the ratio of the angular rate or rotational angle of the standing wave formed in an elastic resonator with respect to that of the platform. In this paper the precession of a hemispherical resonator due to Coriolis' effect is studied through Rayleigh-Ritz's method and Lagrangian Mechanics when the resonator undergoes Rayleigh's mode deformation. The calculation result was compared with studies by other researchers.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.12
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• pp.169-181
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• 2021

The study aims to investigate the direct effects of business management practices in terms of financial, marketing, human resources, and logistics operations practices on sales revenue and profitability growth of freight forwarding businesses. A quantitative research design and partial least square-structural equation modeling were used to examine the direct effects of the exogenous and endogenous variables. The study reveals that financial, marketing, and human resources practices have a positive and significant effect on sales revenue growth. Furthermore, marketing and logistics operations have a positive and significant effect on profitability growth in the context of freight forwarding in the Philippines, particularly in its country's capital. As the current study only examines the direct effects of business management practices, other researchers may also want to consider identifying other variables as mediation and moderation to test other indirect effects on the financial performance of the business. The findings of the study can significantly benefit the freight industry to consider addressing other challenges or make use of the paper to further develop their strategies and practices to improve their financial performance.

• Structural Engineering and Mechanics
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• v.70 no.1
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• pp.113-123
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• 2019

In the classical stability investigation of rectangular plates the classical thin plate theory (CPT) is often employed, so omitting the transverse shear deformation effect. It seems quite clear that this procedure is not totally appropriate for the investigation of moderately thick plates, so that in the following the first shear deformation theory proposed by Meksi et al. (2015), that permits to consider the transverse shear deformation influences, is used for the stability investigation of simply supported isotropic rectangular plates subjected to uni-axial and bi-axial compression loading. The obtained results are compared with those of CPT and, for rectangular plates under uniaxial compression, a novel direct formula, similar to the conventional Bryan's expression, is found for the Euler stability stress. The accuracy of the present model is also ascertained by comparing it, with model proposed by Piscopo (2010).

• YAKHAK HOEJI
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• v.56 no.6
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• pp.401-406
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• 2012

Previously, we identified that Cirsium japonicum (CJ) extract posses antidepressant properties. In order to look for the optimal hebal preparation, CJ extracts collected from Koheung, Yesan, Cheju, Pyungchang and Pocheon were compared. The psychopharmacological activities of each extract were investigated using the open field test, the rota-rod test and the forced swimming test. Effect of each extract on $Cl^-$ influx in neuroblastoma cells were also identified. All of the extracts were orally administered at dosages of 50, 100, 200, 400 mg/kg of body weight. Supplementation of CJ did not significantly alter psychomotor behaviors such as movement, rearing frequency and total turn angle on the open field. Supplementation of CJ's extract from Pyungchang (100 mg/kg, p.o.), Cheju (200 and 400 mg/kg p.o.) and Yesan (100 and 200 mg/kg, p.o.) significantly decreased immobile duration and increased mobile duration in the forced swimming test. All of extracts have no influence on NE uptake in HEK-293 cells, but increased $Cl^-$ influx in neuroblastoma cell. The extract from Yesan demonstrated the most potent effect on $Cl^-$ influx. These results indicate that CJ's extracts from Pyungchang, Cheju and Yesan may alleviate depression, and the extract from Yesan may be the most effective preparation.

• Natural Product Sciences
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• v.23 no.1
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• pp.40-45
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• 2017

Epilepsy is a brain disorder that affects millions of people worldwide. It is characterized by recurrent and unpredictable seizures that are usually controlled with antiepileptic/anticonvulsive drugs. However, most antiepileptic drugs produce various side effects such as tolerance and sedation. Thus, there is a growing interest for alternative anticonvulsive drugs, preferably from natural or herbal sources. In this study, we evaluated the anticonvulsive effects of Rehmannia glutinosa (RG). The anticonvulsive effect of RG extract was evaluated using electroshock- and chemical-induced seizure tests in mice. To identify its probable mechanism of action, the effects of RG extract on $Cl^-$ influx was measured in vitro. We found that RG extract has anticonvulsive effects against electroshock-induced seizures, as indicated by an increased seizure threshold in mice. The RG extract also decreased the percentage of seizure responses induced by the GABAergic antagonist, pentylenetetrazole. These results suggest that the anticonvulsive effects of RG extract are mediated through a GABAergic mechanism. In support of this mechanism, our in vitro test showed that RG extract increases intracellular $Cl^-$ influx. Furthermore, RG extract did not show sedative and/or muscle relaxant effects in the open-field and rota-rod tests. Altogether, these results confirm that RG extract could be a herbal anticonvulsant and a potential alternative for clinical use.