• Journal of the Korea Institute of Military Science and Technology
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• v.5 no.2
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• pp.116-122
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• 2002

Electro Explosive Devices can be susceptible to electromagnetic interference. When these components are exposed to external electromagnetic fields, it may cause to induce sufficient current to generate enough heat for an inadvertent detonation. It is almost impossible to monitor the event of firing throughout the electromagnetic environment test. The survivability of EED for hazards of electromagnetic radiation is investigated. A fiber optic sensor is installed near the bridge wire after removing explosive material in order to measure the induced current on the bridge wire. The length of lead-wire of the EED fabricated is around 15 cm.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.142-149
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• 2019

In this study, the past erosion history and current status in the CHUNG-UI beach of Eulwang-dong, Jung-gu, Incheon-Si, South Korea were investigated and analyzed the wave with wave-induced current to investigate the causes of coastal erosion. As a result, the significant wave height ($H_{1/3}$) was in the range of 0.07~1.57 m and the mean value was 0.21 m. The maximum wave height ($H_{max}$) was in the range of 0.02-4.76m and the mean value was 0.27m. The vertical wave height and cycles were estimated through numerical model experiments of wave transformation. The 50-year frequency design wave height ranged from 0.82m to 3.75m. As a result of the experiment of wave-induced current, wave-induced current in the CHUNG-UI beach was decreased after the installation of the Detached breakwater and the Jetty. On the other hand, when the crest elevation was increased up to 5 m, there was no significant change, but when the crest elevation was increased to 8m, strong wave-induced current occurred around the submerged breakwaters due to lowered depth of water. In addition, the main erosion of the CHUNG-UI beach is due to the intensive invasion of the wave characteristics coming from the outer sea into the white sandy beach. The deformation of the wave centered on the front of the sandy beach caused additional longshore currents flowing parallel to the sandy beach and rip currents in the transverse direction, thus confirming that the longshore sediment was moved out of the front and out of the sea. The results of this study can be used as preliminary data for the recovery of the sand and the selection of efficient erosion prevention facilities.

• Korean Journal of Acupuncture
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• v.18 no.1
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• pp.143-156
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• 2001

Modulatory effect of cAMP-PKA system on inhibitory- and excitatory herbs-induced ion currents were investigated by nystatin-perforated patch clamp method under voltage-clamp condition. Ion currents induced by Bupleuri radix and Coptidis rhizoma were not affected by cAMP-PKA system. Ion current induced by Ecliptae herba was partially inhibited by cAMP-PKA system. Ion currents induced by Aconiti tuber and Boshniakiae herba were inhibitory modulated and ion current induced by Zingiberis rhizoma was excitatory modulated by cAMP-PKA system. Modulation of cAMP-PKA system on ion currents induced by Ginseng radix was fluctuated. In this results, it can be seen generally that excitatory herbs-induced ion currents were modulated by cAMP-PKA system while cAMP-PKA system did not affect inhibitory herbs-induced ion currents.

• Korea journal of population studies
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• v.25 no.1
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• pp.5-32
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• 2002

This research explores the current situation and determinants of induced abortion in Korea. Using 2000 National fertility Survey by Korea Institute of Health and Social Affairs, this study finds that induced abortion rate is rapidly declining so that the role of induced abortion in determining the level of fertility has disappeared. The fundamental reason for resorting to an induced abortion for Korean women is to avoid unwanted birth. Thus, we find that induced abortion is usually taken by Korean women for the purpose of limiting family size and spacing births as in any other countries. Premarital pregnancy and economic hardship are also important reason for taking an induced abortioin, especially for the first time abortion.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.17 no.3
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• pp.202-212
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• 2005

In the design of an of offshore structure located near an underwater shoal, the same amount of attention given to the wave height may have to be put to the wave induced current as well since some of the wave energy translates to the current. In the present study, two numerical models each based on the nonlinear Boussinesq equation and the linear mild slope equation are applied to calculate the wave deformation and secondly induced current around a shoal. The underwater shoal in Vincent and briggs' experiment (1989) is used here, and all non-breaking wave conditions of the experiment with various monochromatic and unidirectional or multidirectional spectral wave incidences are concerned. Both numerical models clearly showed wave induced currents symmetrically farmed along the centerline over the shoal. The calculated wave heights along a preset line also generally showed very nice agreements with the experimental values.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.2
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• pp.177-181
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• 2015

The subfornical organ (SFO) is one of circumventricular organs characterized by the lack of a normal blood brain barrier. The SFO neurons are exposed to circulating glutamate ($60{\sim}100{\mu}M$), which may cause excitotoxicity in the central nervous system. However, it remains unclear how SFO neurons are protected from excitotoxicity caused by circulating glutamate. In this study, we compared the glutamate-induced whole cell currents in SFO neurons to those in hippocampal CA1 neurons using the patch clamp technique in brain slice. Glutamate ($100{\mu}M$) induced an inward current in both SFO and hippocampal CA1 neurons. The density of glutamate-induced current in SFO neurons was significantly smaller than that in hippocampal CA1 neurons (0.55 vs. 2.07 pA/pF, p<0.05). To further identify the subtype of the glutamate receptors involved, the whole cell currents induced by selective agonists were then compared. The current densities induced by AMPA (0.45 pA/pF) and kainate (0.83 pA/pF), non-NMDA glutamate receptor agonists in SFO neurons were also smaller than those in hippocampal CA1 neurons (2.44 pA/pF for AMPA, p<0.05; 2.34 pA/pF for kainate, p< 0.05). However, the current density by NMDA in SFO neurons was not significantly different from that of hippocampal CA1 neurons (1.58 vs. 1.47 pA/pF, p>0.05). These results demonstrate that glutamate-mediated action through non-NMDA glutamate receptors in SFO neurons is smaller than that of hippocampal CA1 neurons, suggesting a possible protection mechanism from excitotoxicity by circulating glutamate in SFO neurons.

• International Journal of Oral Biology
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• v.36 no.2
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• pp.71-78
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• 2011

Using whole cell current- and voltage-clamp recording we investigated the characteristics and pharmacology of group I metabotropic glutamate receptor (mGluR)-mediated responses in rat medial vestibular nucleus (MVN) neurons. In current clamp conditions, activation of mGluR I by application of the group I mGluR agonist (R,S)-3,5-dihydroxyphenylglycine (DHPG) induced a direct excitation of MVN neurons that is characterized by depolarization and increased spontaneous firing frequency. To identify which of mGluR subtypes are responsible for the various actions of DHPG in MVN, we used two subtype-selective antagonists. (S)-(+)- alpha-amino-a-methylbenzeneacetic acid (LY367385) is a potent competitive antagonist that is selective for mGluR1, whereas 2-methyl-6-(phenylethynyl)-pyridine (MPEP) is a potent noncompetitive antagonist that is selective for mGluR5. In voltage clamp conditions, DHPG application increased the frequency of spontaneous and miniature inhibitory postsynaptic currents (IPSCs) but had no effect on amplitude distributions. Antagonism of the DHPG-induced increase of miniature IPSCs required the blockade of both mGluR1 and mGluR5. DHPG application induced an inward current, which can be enhanced under depolarized conditions. DHPG-induced current was blocked by LY367385, but not by MPEP. Both LY367385 and MPEP antagonized the DHPG-induced suppression of the calcium activated potassium current ($I_{AHP}$). These data suggest that mGluR1 and mGluR5 have similar roles in the regulation of the excitability of MVN neurons, and show a little distinct. Furthermore, mGluR I, via pre- and postsynaptic actions, have the potential to modulate the functions of the MVN.

• Ocean Systems Engineering
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• v.12 no.3
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• pp.301-333
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• 2022

Herein, we report meaningful and selective review of the progress made on 'Vortex Induced Vibration (VIV)' and 'Vortex Induced Motion (VIM)' of 'Structures of Specific Shapes (SoSS)' subjected to steady uniform flow and of relevance to/in marine structures. Important and critical elements of the numerical methods, experimental methods, and physical ideas are listed and analysed critically and the limitations of the current state of art of VIV/VIM are discussed in-detail. Our focus and aim are to analyse the existing researches with respect to the application in analyses, design and production of marine structures and the reported reviews centre on these only. We identify the critical and important issues that exist in the current literature and utilise these issues to highlight the challenges that need to be tackled to design and develop new age marine structures that can exist and operate safely in the areas of dominance by the VIV/VIM. Finally, we also identify some areas for future scope of research on VIV/VIM.

• Journal of Biomedical Engineering Research
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• v.27 no.1
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• pp.30-37
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• 2006

Injecting currents into an electrically conducting subject, we may measure the induced magnetic flux density distributions using an MRI scanner. The measured data are utilized to reconstruct cross-sectional images of internal conductivity and current density distributions in Magnetic Resonance Electrical Impedance Tomography (MREIT). Injection currents are usually provided in a form of mono-polar or bi-polar pulses synchronized with an MR pulse sequence. Given an MRI scanner performing the MR phase imaging to extract the induced magnetic flux density data, the current source becomes one of the key parts determining the signal-to-noise ratio (SNR) of the measured data. Since this SNR is crucial in determining the quality of reconstructed MREIT images, special care must be given in the design and implementation of the current source. This paper describes a current source design for MREIT with features including interleaved current injection, arbitrary current waveform, electrode switching to discharge any stored charge from previous current injections, optical isolation from an MR spectrometer and PC, precise current injection timing control synchronized with any MR pulse sequence, and versatile PC control program. The performance of the current source was verified using a 3T MRI scanner and saline phantoms.

• Therapeutic Science for Rehabilitation
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• v.8 no.4
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• pp.7-18
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• 2019

Objective : This systematic review aimed to investigate the impact of transcranial direct current stimulation combined with constraint-induced movement therapy (CIMT) in patients with stroke Methods : PubMed and NDSL databases were employed to review literature published between January 2009 and December 2018. The main search terms were "Transcranial direct current stimulation" or "tDCS," "Constraint-induced movement therapy" or "CIMT," "Upper extremity function," "Upper limb," and "Stroke." Based on the inclusion and exclusion criteria, 6 articles were selected. Furthermore, intervention effects on upper extremity function, activities of daily living, and cortical activity were assessed. Results : The current intensity, application time, and protocol of the CIMT varied the between studies. However, the intervention procedures to perform CIMT immediately after transcranial direct current stimulation was the same. Transcranial direct current stimulation combined with CIMT was effective in improving upper limb function and activities of daily living in patients with stoke and had a significant effect on cerebral cortex activation. Conclusions : This study provides information on transcranial direct current stimulation combined with CIMT for use by clinical therapists. Further studies are needed to standardize the stimulation time, current intensity, and electrode attachment position. Furthermore, randomized controlled trials, including long-term follow up, are needed for larger populations using the most appropriate CIMT protocol.