• Title/Summary/Keyword: P-waves

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Performance Verification of the Gas Insulated Switchgear using UHF Partial Discharge Diagnosis Method (UHF 부분방전 진단법에 의한 가스절연 개폐장치의 성능검증)

  • Kim, J.B.;Jung, J.R.;Kim, M.S.;Song, W.P.;Kim, M.H.;Ko, H.S.;Choi, I.H.
    • Proceedings of the KIEE Conference
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    • 2004.05b
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    • pp.132-135
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    • 2004
  • In generally, compared with VHF band, electromagnetic waves of UHF band have a low influence for external noise. We can detect the real abnormality with several pC in GIS using UHF method. Recently, it has applied to use the external UHF sensor attached on spacer to GIS of existing substation. In this paper, we firstly described the technique of the partial discharge measurement using frequency analysis and phase analysis in UHF band. Secondly, we presented the results of sensitivity, the relationship of dBm-pC and diagnosis of the reason of PD source by phase analysis. And then, we report the diagnosis result of partial discharge on 800kV GIS in domestic substation. rge diagnosis of GIS.

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Acupuncture for Attenuating Frontal Lobe α Band Asymmetry Induced by Anger: a pilot study

  • Sung-A Kim;Yujin Choi;Seung-Hun Cho
    • Journal of Pharmacopuncture
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    • v.26 no.3
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    • pp.276-284
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    • 2023
  • Objectives: Previous studies have shown that anger can lead to frontal lobe α (8-13 Hz) band asymmetry (FAA) in electroencephalogram (EEG), in accordance with motivational direction. This pilot study aimed to investigate the impact of acupuncture on FAA elicited by anger. Methods: Thirty-four right-handed participants scoring above 75 points on the Novaco Anger Scale were included. Baseline EEG signals were recorded for eight minutes using a 32-channel cap under comfortable conditions. Anger was induced through a nine-minute sequence of Articulated Thoughts in Simulated Situations (ATSS) task. Following that, participants received acupuncture at GB20 and GB21 for 10 minutes. Fast Fourier transform was employed for frequency analysis, and repeated measure ANOVA was conducted for statistical analysis. Results: The results revealed that participants exhibited significantly higher FAA (p = 0.026), particularly in the left hemisphere, after the ATSS task sequence compared to the baseline. During acupuncture treatment, the greater left-sided FAA was significantly reduced (p = 0.027) and reversed. Upon the cessation of acupuncture, FAA returned to a value between the baseline and the anger-evoked stage (p = 0.046). Conclusion: The EEG results of this study revealed that anger stimulation induced an increase in left-sided FAA, which was effectively alleviated by acupuncture. This led to an immediate restoration of FAA asymmetry induced by anger. These findings suggest the potential of acupuncture as a treatment option for reducing FAA associated with anger.

Comparative Study on the Attenuation of P and S Waves in the Crust of the Southeastern Korea (한국 남동부 지각의 P파와 5파 감쇠구조 비교연구)

  • Chung, Tae-Woong
    • Journal of the Korean earth science society
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    • v.22 no.2
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    • pp.112-119
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    • 2001
  • The Yangsan fault in the southeastern Korea has been receiving increasing attention in its seismic activity. In this fault region, by using the extended coda-normalization method for 707 seismograms of local earthquakes, were obtained 0.009f$^{-1.05}$ and 0.004f$^{-0.70}$ for fitting values of Q$_p^{-1}$ and Q$_s^{-1}$, respectively. These results indicate that Q$_p^{-1}$ and Q$_s^{-1}$ in the southeastern Korea is the lowest level in the world although the exponent values agree well with those in the other areas. The low Q-1 is not related to the movement of the Yangsan fault but to the tectonically inactive status like a shield area.

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Characteristics of late-onset epilepsy and EEG findings in children with autism spectrum disorders

  • Lee, Ha-Neul;Kang, Hoon-Chul;Kim, Seung-Woo;Kim, Young-Key;Chung, Hee-Jung
    • Clinical and Experimental Pediatrics
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    • v.54 no.1
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    • pp.22-28
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    • 2011
  • Purpose: To investigate the clinical characteristics of late-onset epilepsy combined with autism spectrum disorder (ASD), and the relationship between certain types of electroencephalography (EEG) abnormalities in ASD and associated neuropsychological problems. Methods: Thirty patients diagnosed with ASD in early childhood and later developed clinical seizures were reviewed retrospectively. First, the clinical characteristics, language and behavioral regression, and EEG findings of these late-onset epilepsy patients with ASD were investigated. The patients were then classified into 2 groups according to the severity of the EEG abnormalities in the background rhythm and paroxysmal discharges. In the severe group, EEG showed persistent asymmetry, slow and disorganized background rhythms, and continuous sharp and slow waves during slow sleep (CSWS). Results: Between the two groups, there was no statistically significant difference in mean age (P=0.259), age of epilepsy diagnosis (P=0.237), associated family history (P=0.074), and positive abnormal magnetic resonance image (MRI) findings (P=0.084). The severe EEG group tended to have more neuropsychological problems (P=0.074). The severe group statistically showed more electrographic seizures in EEG (P=0.000). Rett syndrome was correlated with more severe EEG abnormalities (P=0.002). Although formal cognitive function tests were not performed, the parents reported an improvement in neuropsychological function on the follow up checkup according to a parent's questionnaire. Conclusion: Although some ASD patients with late-onset epilepsy showed severe EEG abnormalities, including CSWS, they generally showed an improvement in EEG and clinical symptoms in the longterm follow up. In addition, severe EEG abnormalities tended to be related to the neuropsychological function.

A Study on S-wave Reflection method for the assessment of physical property of dam body (댐체 물성 평가를 위한 S파 반사법에 관한 연구)

  • Kim, Hyoung-Soo;Kim, Jung-Yul;Ha, Ik-Soo;Kim, Yoo-Sung
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.392-399
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    • 2005
  • Shear modulus (or rigidity) of dam material is an important parameter which can be directly associated with the deformation of dam. Seepage or leakage of water can cause the defects or cracks of dam body. The existence of cracks and rigidity of dam body are decisive information for the estimation of dam safety. Rigidity of material is mainly determined from S-wave velocity and the defects of dam body can be detected by seismic reflection survey. Therefore, seismic reflection survey will be a desirable method which can give a solution about dam safety problem. Among various physical properties of dam body, S-wave velocity is the most important information but it is not easy to get the information. In this study, diverse measuring techniques of S-wave reflection survey were attempted to get the information about S-wave velocity of dam body. Ultimately, S-wave velocity could be estimated by the analysis of SH reflection events which can be easily observed in shot gather data obtained from SH measuring technique. Meanwhile, P-wave reflection survey was also performed at the same profile. P-beam radiation technique which can reduce the surface waves and reinforce the P-wave reflection events was applied for giving a help to analyse P-wave velocity. In the end, P-and S-wave velocity, Vs/Vp, Poisson's ratio distribution of the vertical section under the profile could be acquired.

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Effect of Jichul-hwan on Gastric Motility in Conscious and Gastric Wall Injured Rats (지출환(枳朮丸)의 흰쥐 위(胃) 운동성(運動性)에서 정상 상태 및 위벽 국소손상 후에 대한 효능)

  • Lee, Seung-Woo;Yoon, Sang-Hyub
    • The Journal of Internal Korean Medicine
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    • v.29 no.1
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    • pp.189-199
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    • 2008
  • Background & Objective : Jichul-hwan(JCH) has been used for the treatment of functional dyspepsia, regarded as a gastric dysmotility disease. We investigated the effects of JCH on gastric motility and its mechanisms of action in rats. Methods : The gastric wall was injured by tracting a part of stomach body in rats. Gastric emptying was measured after administration of normal saline(NS) or JCH in normal rats and gastric wall injured rats. To evaluate the mechanism of JCH under delayed gastric emptying conditions, normal rats were treated with atropine sulfate(1mg/kg, s.c.), quinpirole HCl(0.3mg/kgg, i.p.), $NAME(N^{G}-nitro-L-arginine$ methyl ester, 75mg/kg s.c.) and cisplatin(10mg/kg, i.p.). The gastric slow waves were measured for 30 minutes before and after administration of each solution(NS, JCH). Results : JCH 110.1mg/kg improved gastric emptying for 2 hrs(p=0.014). JCH 110.1mg/kg improved gastric emptying in the gastric wall injured rats(p=0.001). Under the delayed gastric emptying, JCH 110.1mg/kg improved gastric emptying in the group treated with atropine $sulfate(1.83{\pm}0.96$ vs $8.43{\pm}8.46$, p=0.003), but aggravated it with quinpirole $HCl(4.7{\pm}2.9$ vs $1.61{\pm}2.09$, p=0.021). Administration JCH 110.1mg/kg increased EGG power in rats. Conclusions : JCH stimulates gastric motility through the cholinergic pathway, so we expect that it would be effective in the treatment of dysmotility-like functional dyspepsia with low activity of vagus nerve.

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Effects of degree of Use of Smartphone on the Spinal Health of Later Teens: Moderating Effect of Cognition Strength (스마트폰 사용정도에 따라 후기 청소년들의 척추건강에 미치는 영향: 인지강도의 조절효과 중심으로)

  • Kim, Sang-Woo;Lee, Jin;Lee, Byoung-Hee
    • 재활복지
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    • v.22 no.2
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    • pp.213-230
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    • 2018
  • The study looked at the impact on the health of the spine caused by the increasing addiction to smart phones, and examine the moderating effect of adjusting spinal health according to cognitive strength. All subjects used the smartphone by measuring the diagnostic scale of the smartphone addiction, the angle of forward inclination of the cervical spine, and the amplitude variation of the cognitive Gamma-Peak of the brain waves. As a result, as the use of smart phones increases, the spine angle significantly increased (p<0.001), as cognitive strength increased, the spine angle decreased significantly (p<0.01). The cognitive strength also showed the effect of adjusting the spine angle through interaction with the degree of use of a smartphone (p<0.05). This results in a higher degree of smartphone use in lower and middle cognition strength groups, which results in a higher angle of forward tilt in the cervical spine.

Analysis of Surface Plasmon Resonance on Periodic Metal Hole Array by Diffraction Orders

  • Hwang, Jeong-U;Yun, Su-Jin;Gang, Sang-U;No, Sam-Gyu;Lee, Sang-Jun;Urbas, Augustine;Ku, Zahyun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.176-177
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    • 2013
  • Surface plasmon polaritons (SPPs) have attracted the attention of scientists and engineers involved in a wide area of research, microscopy, diagnostics and sensing. SPPs are waves that propagate along the surface of a conductor, usually metals. These are essentially light waves that are trapped on the surface because of their interaction with the free electrons of conductor. In this interaction, the free electrons respond collectively by oscillating in resonance with the light wave. The resonant interaction between the surface charge oscillation and the electromagnetic field of the light constitutes the SPPs and gives rise to its unique properties. In this papers, we studied theoretical and experimental extraordinary transmittance (T) and reflectance (R) of 2 dimensional metal hole array (2D-MHA) on GaAs in consideration of the diffraction orders. The 2d-MHAs was fabricated using ultra-violet photolithography, electron-beam evaporation and standard lift-off process with pitches ranging from 1.8 to $3.2{\mu}m$ and diameter of half of pitch, and was deposited 5-nm thick layer of titanium (Ti) as an adhesion layer and 50-nm thick layer of gold (Au) on the semiinsulating GaAs substrate. We employed both the commercial software (CST Microwave Studio: Computer Simulation Technology GmbH, Darmstadt, Germany) based on a finite integration technique (FIT) and a rigorous coupled wave analysis (RCWA) to calculate transmittance and reflectance. The transmittance was measured at a normal incident, and the reflectance was measured at variable incident angle of range between $30^{\circ}{\sim}80^{\circ}$ with a Nicolet Fourier transmission infrared (FTIR) spectrometer with a KBr beam splitter and a MCT detector. For MHAs of pitch (P), the peaks ${\lambda}$ max in the normal incidence transmittance spectra can be indentified approximately from SP dispersion relation, that is frequency-dependent SP wave vector (ksp). Shown in Fig. 1 is the transmission of P=2.2 um sample at normal incidence. We attribute the observation to be a result of FTIR system may be able to collect the transmitted light with higher diffraction order than 0th order. This is confirmed by calculations: for the MHAs, diffraction efficiency in (0, 0) diffracted orders is lower than in the (${\pm}x$, ${\pm}y$) diffracted orders. To further investigate the result, we calculated the angular dependent transmission of P=2.2 um sample (Fig. 2). The incident angle varies from 30o to 70o with a 10o increment. We also found the splitting character on reflectance measurement. The splitting effect is considered a results of SPPs assisted diffraction process by oblique incidence.

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Behavior of an Automatic Pacemaker Sensing Algorithm for Single-Pass VDD Atrial Electrograms (Single-Pass VDD 심파를 위한 자동화된 심장 박동기 탈분극파 검출 알고리즘의 효용성)

  • Kim, Jung-Kuk;Lee, Seung-Han;Huh, Woong
    • Journal of IKEEE
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    • v.5 no.2 s.9
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    • pp.182-189
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    • 2001
  • Single-pass VDD pacemakers have been used as a result of simple implantation procedures and generally reliable atrial tracking that ensures an A-V sequence pacing. However, there is a controversy over their reliabilities of atrial tracking. As a new sensing method for reliable atrial tracking, a simple automatic pacemaker sensing algorithm was implemented and evaluated to validate its benefits in sensing depolarization waves of Single-pass VDD atrial electrograms. The automatic sensing algorithm had a predetermined sensing dynamic range and the sensitivity level was controlled as 50% of the average of two most recently sensed intrinsic amplitudes. The behavior of the automatic sensing algorithm in the Single-pass VDD atrial electrograms was analyzed and characterized. It was observed that the automatic sensing algorithm was more effective than a conventional fixed threshold method to accurately detect and track p-waves in Single-pass VDD electrograms.

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Properties of Spontaneous Activity in Gastric Smooth Muscle

  • Suzuki, H.;Yamamoto, Y.;Hirst, G.D.S.
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.2
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    • pp.119-125
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    • 1999
  • Mammalian gastric smooth muscles generate spontaneous rhythmic contractions which are associated with slow oscillatory potentials (slow waves) and spike potentials. Spike potentials are blocked by organic $Ca^{2+}-antagonists,$ indicating that these result from the activation of L-type $Ca^{2+}-channel.$ However, the cellular mechanisms underlying the generation of slow wave remain unclear. Slow waves are insensitive to $Ca^{2+}-antagonists$ but are blocked by metabolic inhibitors or low temperature. Recently it has been suggested that Interstitial Cells of Cajal (ICC) serve as pacemaker cells and a slow wave reflects the coordinated behavior of both ICC and smooth muscle cells. Small segments of circular smooth muscle isolated from antrum of the guinea-pig stomach generated two types of electrical events; irregular small amplitude (1 to 7 mV) of transient depolarization and larger amplitude (20 to 30 mV) of slow depolarization (regenerative potential). Transient depolarization occurred irregularly and membrane depolarization increased their frequency. Regenerative potentials were generated rhythmically and appeared to result from summed transient depolarizations. Spike potentials, sensitive to nifedipine, were generated on the peaks of regenerative potentials. Depolarization of the membrane evoked regenerative potentials with long latencies (1 to 2 s). These potentials had long partial refractory periods (15 to 20 s). They were inhibited by low concentrations of caffeine, perhaps reflecting either depletion of $Ca^{2+}$ from SR or inhibition of InsP3 receptors, by buffering $Ca^{2+}$ to low levels with BAPTA or by depleting $Ca^{2+}$ from SR with CPA. They persisted in the presence of $Ca^{2+}-sensitive$ $Cl^--channel$ blockers, niflumic acid and DIDS or $Co^{2+},$ a non selective $Ca^{2+}-channel$ blocker. These results suggest that spontaneous activity of gastric smooth muscle results from $Ca^{2+}$ release from SR, followed by activation of $Ca^{2+}-dependent$ ion channels other than $Cl^-$ channels, with the release of $Ca^{2+}$ from SR being triggered by membrane depolarization.

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