• Title/Summary/Keyword: amplitude difference

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Cardiovascular response to surprise stimulus (놀람 자극에 대한 심혈관 반응)

  • Eom, Jin-Sup;Park, Hye-Jun;Noh, Ji-Hye;Sohn, Jin-Hun
    • Science of Emotion and Sensibility
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    • v.14 no.1
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    • pp.147-156
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    • 2011
  • Basic emotions such as happiness, sadness, anger, fear, and disgust have been widely used to investigate emotion-specific autonomic nervous system activity in many studies. On the contrary, surprise emotion, Suggested also as one of the basic emotions suggested by Ekman et al. (1983), has been least investigated. The purpose of this study was to provide a description of cardiovascular responses on surprise stimulus using electrocardiograph (ECG) and photoplethysmograph (PPG). ECG and PPG were recorded from 76 undergraduate students, as they were exposed to a visuo-acoustic surprise stimulus. Heart rate (HR), standard deviation of R-R interval (SD-RR), root mean square of successive R-R interval difference (RMSSD-RR), respiratory sinus arrhythmia (RSA), finger blood volume pulse amplitude (FBVPA), and finger pulse transit time (FPTT) were calculated before and after the stimulus presentation. Results show significant increase in HR, SD-RR, and RMSSD-RR, decreased FBVPA, and shortened FPTT. Evidence suggests that surprise emotion can be characterized by vasoconstriction and accelerated heart rate, sympathetic activation, and increased heart rate variability, parasympathetic activation. These results can be useful in developing an emotion theory, or profiling surprise-specific physiological responses, as well as establishing the basis for emotion recognition system in human-computer interaction.

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A Study on the Applicability of Arias Intensity Liquefaction Assessment (Arias Intensity 액상화 평가기법의 적용성에 관한 연구)

  • Hwang, Jungtae;Lee, Jongkeun;Shin, Eunchul
    • Journal of the Korean GEO-environmental Society
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    • v.14 no.6
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    • pp.13-19
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    • 2013
  • In this study, the target ground was selected for the assessment of liquefaction, for which energy-based Arias intensity liquefaction assessment method was applied, The results of evaluation by simplified method using conventional in-situ test were compared. The result of the assessment of liquefaction revealed that the safety factor of the Arias Intensity using the actual records of the Hachinohe and Ofunato earthquake showed generally similar trends with the simplified method, However, the Arias Intensity factor of safety for the artificial earthquake created from the design response spectrum showed some difference from the factors of safety of the simplified method. The shear stress ratio and the occurrence strength of the Arias Intensity are differently calculated between stress and energy, but the resistance stress ratio of the simplified method and the resistance strength of the Arias Intensity use the empirical chart of the results of the standard penetration test for the actual liquefaction areas by the earthquake, which seems the reason for the similar results between Arias Intensity assessment and stress concept simplified method for Hachinohe and Ofunato earthquakes. Therefore, it was found that the energy-based Arias Intensity liquefaction assessment could represent the dynamic changes of the ground caused by seismic characteristics such as acceleration, magnitude, duration and amplitude.

Experimental Performance Evaluation according to the Sticked Backside Plate of Dipole Antenna for RFID Tag (RFID 태그용 다이폴 안테나의 부착 지판에 따른 실험적 성능 평가)

  • Min, Kyeong-Sik;Kim, Jin-Woo
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.18 no.3 s.118
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    • pp.273-281
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    • 2007
  • This paper presented design for a dipole antenna operated at 900 MHz band RFID tag, and antenna performance varied by the sticked material was experimentally evaluated. When dipole antenna was sticked by the material having a difffrent electric characteristic such as dielectric material, fero-magnetic material and conductor, variations of antenna return loss and radiation pattern according to the sticked material kinds, size, and height between antenna and the sticked plate were experimentally observed and evaluated. When antenna was sticked by dielectric surface, the measured return loss and radiation pattern by affection of different dielectric permittivity ratio showed resonant frequency shift of about 40 MHz and relative attenuation of 1 dB to 3 dB. Even though frequency shift by size variation of the sticked plate was observed, the measured radiation pattern of dipole antenna located on the sticked plate was similar with one without backside plate. In the case of conductor or fero-magnetic material as the sticked ground plate, because of frequency shift and phase difference by distance between dipole antenna and the sticked ground plate, amplitude decrease of radiation pattern at 910 MHz was observed about 5 dB above.

A Study on the Cyclic Hardening Property and the Low Cycle Fatigue Behavior of Marine Materials (박용재료(舶用材料)의 반복경화(反復硬化) 및 저(低)싸이클 피로특성(疲勞特性)에 관한 연구)

  • S.M. Cho;K. Horikawa
    • Journal of the Society of Naval Architects of Korea
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    • v.28 no.1
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    • pp.108-116
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    • 1991
  • In the non-linear behavior of many materials, there is difference between the monotonic behavior by static load and the cyclic behavior by cyclic load. In particular, the short fatigue cracks to propagate in elasto-plastic stress concentrations(notches), are governed significantly by the cyclic behavior of materials. Accordingly, it is needed to investigate and compare the monotonic and cyclic behavior of materials. In the pressent study, the stress-strain relations of materials by monotonic and cyclic load tests were examined for 2 kinds of steels(SS41, HT80) and 5 kinds of Al-alloys(A5083-O, A6N01-T5, A7N01-T4, A7016-T6, A7178-T6). And the constants for mechanical properties of the materials were determined by experimental results, Moreover, when a notch was subjected to cyclic load, the effect of cyclic hardening property of materials on the variation of stress-strain amplitude in the notch tip was discussed by the application of Neuber's rule and experiments for a center notched plate.

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Seismic Properties Study of Gas Hydrate in Deep Sea using Numerical Modeling Technique (수치 모델링 기술을 이용한 심해 가스 하이드레이트의 탄성파 특성 연구)

  • Shin, Sung-Ryul;Yeo, Eun-Min;Kim, Chan-Su;Park, Keun-Pil;Lee, Ho-Young;Kim, Young-Jun
    • Geophysics and Geophysical Exploration
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    • v.9 no.2
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    • pp.139-147
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    • 2006
  • We had conducted a numerical modeling to investigate seismic properties of gas hydrate with field parameters acquired over the East sea in 1998. We used a 2-D staggered grid finite difference method to generate synthetic elastic seismograms for multi-channel seismic survey, OBC (Ocean Bottom Cable) survey and VCS (Vertical Cable Seismic) survey. The results of this study showed that the method using staggered grid yielded stable results and could be used to seismic imaging. We could find out the high amplitude anomaly and the phase reversal phenomenon of reflection wave at interface between the gas hydrate layer and free gas layer such a BSR (Bottom Simulating Reflector) which is the evidence for existence of gas hydrate in seismic reflection data. And we computed the reflection coefficients at the incident angles corresponding to offset distance with the synthetic seismograms. The reflection coefficients acquired from the numerical modeling were nearly consistent with the reflection coefficient computed by Shuey's equation.

Application of Image Processing Techniques to GPR Data for the Reliability Improvement in Subsurface Void Analysis (지표레이더(GPR) 탐사자료를 이용한 지하공동 분석 시 신뢰도 향상을 위한 영상처리기법의 활용)

  • Kim, Bona;Seol, Soon Jee;Byun, Joongmoo
    • Geophysics and Geophysical Exploration
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    • v.20 no.2
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    • pp.61-71
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    • 2017
  • Recently, ground-penetrating radar (GPR) surveys have been actively carried out for precise subsurface void investigation because of the rapid increase of subsidence in urban areas. However, since the interpretation of GPR data was conducted based on the interpreter's subjective decision after applying only the basic data processing, it can result in reliability problems. In this research, to solve these problems, we analyzed the difference between the events generated from subsurface voids and those of strong diffraction sources such as the buried pipeline by applying the edge detection technique, which is one of image processing technologies. For the analysis, we applied the image processing technology to the GRP field data containing events generated from the cavity or buried pipeline. As a result, the main events by the subsurface void or diffraction source were effectively separated using the edge detection technique. In addition, since subsurface voids associated with the subsidence has a relatively wide scale, it is recorded as a gentle slope event unlike the event caused by the strong diffraction source recorded with a sharp slope. Therefore, the directional analysis of amplitude variation in the image enabled us to effectively separate the events by the subsurface void from those by the diffraction source. Interpretation based on these kinds of objective analysis can improve the reliability. Moreover, if suggested techniques are verified to various GPR field data sets, these approaches can contribute to semiautomatic interpretation of large amount of GPR data.

Inhibition of L-type Ca2+ current by ginsenoside Rd in rat ventricular myocytes

  • Lu, Cheng;Sun, Zhijun;Wang, Line
    • Journal of Ginseng Research
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    • v.39 no.2
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    • pp.169-177
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    • 2015
  • Background: Ginsenoside Rd (GSRd), one of the most abundant ingredients of Panax ginseng, protects the heart via multiple mechanisms including the inhibition of $Ca^{2+}$ influx.We intended to explore the effects of GSRd on L-type $Ca^{2+}$ current ($I_{Ca,L}$) and define the mechanism of the suppression of $I_{Ca,L}$ by GSRd. Methods: Perforated-patch recording and whole-cell voltage clamp techniques were applied in isolated rat ventricular myocytes. Results: (1) GSRd reduced $I_{Ca,L}$ peak amplitude in a concentration-dependent manner [half-maximal inhibitory concentration $(IC_{50})=32.4{\pm}7.1{\mu}mol/L$] and up-shifted the current-voltage (I-V) curve. (2) GSRd ($30{\mu}mol/L$) significantly changed the steady-state activation curve of $I_{Ca,L}$ ($V_{0.5}:-19.12{\pm}0.68$ vs. $-6.26{\pm}0.38mV$; n = 5, p < 0.05) and slowed down the recovery of $I_{Ca,L}$ from inactivation [the time content (${\zeta}$) from 91 ms to 136 ms, n = 5, p < 0.01]. (3) A more significant inhibitive effect of GSRd ($100{\mu}mol/L$) was identified in perforated-patch recording when compared with whole-cell recording [$65.7{\pm}3.2%$ (n = 10) vs. $31.4{\pm}5.2%$ (n = 5), p < 0.01]. (4) Pertussis toxin ($G_i$ protein inhibitor) completely abolished the $I_{Ca,L}$ inhibition induced by GSRd. There was a significant difference in inhibition potency between the two cyclic adenosine monophosphate elevating agents (isoprenaline and forskolin) prestimulation [$55{\pm}7.8%$ (n = 5) vs. $17.2{\pm}3.5%$ (n = 5), p < 0.01]. (5) 1H-[1,2,4]Oxadiazolo[4,3-a]-quinoxalin-1-one (a guanylate cyclase inhibitor) and N-acetyl-$\small{L}$-cysteine (a nitric oxide scavenger) partly recovered the $I_{Ca,L}$ inhibition induced by GSRd. (6) Phorbol-12-myristate-13-acetate (a protein kinase C activator) and GF109203X (a protein kinase C inhibitor) did not contribute to the inhibition of GSRd. Conclusion: These findings suggest that GSRd could inhibit $I_{Ca,L}$ through pertussis toxin-sensitive G protein ($G_i$) and a nitric oxide-cyclic guanosine monophosphate-dependent mechanism.

The Behavior of Dry Sand under Dynamic Loading -A Study on the Vertical Vibration (건조사질토의 동적거동 -수직진동에 의한 연구)

  • Kim, Su-Il;Jeong, Sang-Seom;An, Yeong-Hun
    • Geotechnical Engineering
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    • v.11 no.4
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    • pp.37-48
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    • 1995
  • The dynamic behavior of dry sand under different vibration conditions is studied through laboratory experiments. Sinusoidal and random vibration experiments of sand are carried out in vertical direction under various surcharge loads. Five different sand samples are selected for the azperiment. They are composed of four different -size samples of particles and one sample which is simulated the field condition. In case of sinusoidal vibration, the change in relative density is measured with acceleration levels. To produce an acceleration, the vibration amplitude is maintained within the range of 0.4mm~0.6mm and the vibration frequency is changed within the range of 3Hz~40Hz. In case of random vibration, the combined sinusoidal acceleration is produced by a random vibration generator and the change in relative density is measured by an accelerometer. Based on the experimental results, it is found that the sandy soil is compacted to 94%~99% of relative density by vertical acceleration and the peak acceleration producing the maximum relative density is proportional to the difference between maximum and minimum void ratios. It is also found that the effect of surcharge loading : the greater the surcharge loading, the larger the change in relative density and the greater the acceleration required to change the relative density.

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Characteristics of Hydrography and Tidal Current in Hampyung Bay, the Western Coast of Korea (서해 함평만의 해수 물성구조 및 조류 특성)

  • Lee, Kyeong-Sig;Jun, Sue-Kyung
    • Journal of the Korean earth science society
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    • v.30 no.2
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    • pp.247-256
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    • 2009
  • Characteristics of hydrography and tidal currents were investigated in Hampyung Bay through in situ CTD data, tidal currents and elevations. According to the seasonal weather variability, hydrography showed the lower density with high temperature and low salinity in summer and the higher density with low temperature and high salinity in winter. In particular, the thermal structure like a tidal front was formed along the central channel at the neap tide of summer. The critical value of the parameter $SH(=log_{10}(H/U^3)$ where H is depth and U is $M_2$ tidal current amplitude) representing the formation position of tidal front was estimated from 2.4 to 3.5. In addition, the potential energy anomaly $({\phi})$ was ranged between 0.985 and 6.998 Joule/$m^3$, which gradually increased from the mouth into the inner bay. This front may be caused by the unique topography with wide tidal flat and the local difference of tidal current strength. The observed tidal currents at the mouth of bay showed that the ebb time was shorter than the flood time with the increase of depth. This asymmetric ebb-tide dominance is interpreted as a result of tidal distortion by the development of a shallow-water-constituent in Hampyung Bay with a wide macro-tidal flat.

Electrophysiological Changes after Low-Power Infrared Laser Irradiation on Injured Rat Sciatic Nerves (손상된 흰쥐의 좌골신경에 저출력 레이저 조사후 전기생리학적 변화)

  • Bae Chun-Sik;Shin Soo-Beom;Kim Kweon-Young
    • Journal of Life Science
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    • v.16 no.1
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    • pp.114-119
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    • 2006
  • The purpose of this study was to determine effects of the Ga-As (Gallium-Arsenide) Dens-Bio laser on mechanically injured sciatic nerves of rats. The improvement of the injured rat sciatic nerve was evaluated by measuring of nerve conduction velocity and amplitude of compound muscle action potential. The sciatic nerves of forty male Sprague-Dawley rats were compressed with hemostatic forceps for 30 seconds. The experimental group was divided into 4 subgroups according to the duration of treatment. Lower power infrared laser irradiation was done transcutaneously to the injured sciatic nerve area, 3 minutes daily to each of four treatment groups for 1, 3, 5, and 7 weeks, respectively. Compound muscle action potential and nerve conduction velocity of sciatic nerve were obtained before nerve injury and at 1, 3, 5, and 7 weeks after injury. There were significant difference of the nerve conduction velocity and amplitudes of compound muscle action potential between the treatment group and non-treatment group at 1, 3, and 5 weeks after laser treatment. However, there were no differences found between the electrophysiologic parameters that were measured after 7 weeks in two groups. There was significant correlation between the increment of compound muscle action potential and nerve conduction velocity after time course according to laser treatment. In conclusion, the low power laser treatment had improved the sciatic nerve function, and therefore these results may provide the basic data to clarify the neurological recovery and treatment after incomplete peripheral nerve injury.