• 제목/요약/키워드: Wave amplitude

검색결과 1,048건 처리시간 0.024초

삶은 계란을 섭취한 흰쥐의 심전도 (Electrocardiograms in the Rats Fed Diets with Boiled Eggs)

  • 박병성
    • 한국축산식품학회지
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    • 제21권3호
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    • pp.272-277
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    • 2001
  • Electrocardiograms in rats fed diets with boiled eggs for 30 days was investigated. Amplitudes of P,Q and R waves were not significant differences among treatment groups. Amplitude of S wave in rats fed the diet with 95% boiled eggs was significantly tended to be increased compared with other groups(P<0.05). Amplitude of T wave in the rats fed the diet with 0% boiled eggs showed the highest values, and there were significant difference among treatment groups fed diets with 0% boiled eggs, 25% and 95% boiled eggs (P<0.05). Durations of P and PQ(PR) waves were high in the rats fed diets with 25% and 50% boiled eggs (P<0.05). Duration of QRS complex showed low in the rats fed diet 0% boiled eggs but not significant difference among treatment groups. Duration of QT was high in the rats fed diet with 0% boiled eggs(P<0.05). This result is assumed that electrocardiograms in the rats is not changed to intake the boiled eggs.

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An Extended Numerical Calibration Method for an Electrochemical Probe in Thin Wavy Flow with Large Amplitude Waves

  • Park, Ki-Yong;No, Hee-Cheon
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1998년도 춘계학술발표회논문집(1)
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    • pp.553-558
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    • 1998
  • The calibrating method for an electrochemical Probe, neglecting the effect of the normal velocity on the mass transport, can cause large errors when applied to the measurement of wall shear rates in thin wavy flow with large amplitude waves. An extended calibrating method is developed to consider the contributions of the normal velocity. The inclusion of the turbulence-induced normal velocity term is found to have a negligible effect on the mass transfer coefficient. The contribution wave-induced normal velocity can be classified on the dimensionless parameter V. If V above a critical value of V, $V_{crit}$, the effects of the wave-induced normal velocity become larger with an increase in V. IF V its effects negligible for V < $V_{crit}$. The unknown shear rate is numerically determined by solving the 2-D mass transport equation inversely. The president inverse method can predict the unknown shear rate more accurately in thin wavy flow with large amplitude waves than the previous method.

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Effect of energy dissipation on plane waves in sandwiched layered thermoelastic medium

  • Lata, Parveen
    • Steel and Composite Structures
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    • 제27권4호
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    • pp.439-451
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    • 2018
  • In the present investigation, a plane P (longitudinal) wave is made incident upon a transversely isotropic magnetothermoelastic solid slab of uniform thickness, interposed between two different semi-infinite viscoelastic solids. The transversely isotropic magnetothermoelastic sandwiched layer is homogeneous with combined effects of two temperature, rotation and Hall current in the context of GN Type-II and Type-III (1993) theory of thermoelasticity. The amplitude ratios of various reflected and refracted waves are obtained by using appropriate boundary conditions. The effect of energy dissipation on various amplitude ratios of longitudinal wave with angle of incidence are depicted graphically. Some cases of interest are also deduced from the present investigation.

π/2 Pulse Shaping via Inverse Scattering of Central Potentials

  • 이창재
    • Bulletin of the Korean Chemical Society
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    • 제17권2호
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    • pp.188-192
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    • 1996
  • It is shown that the inversion of the undamped Bloch equation for an amplitude-modulated broadband π/2 pulse can be precisely treated as an inverse scattering problem for a Schrodinger equation on the positive semiaxis. The pulse envelope is closely related to the central potential and asymptotically the wave function takes the form of a regular solution of the radial Schrodinger equation for s-wave scattering. An integral equation, which allows the calculation of the pulse amplitude (the potential) from the phase shift of the asymptotic solution, is derived. An exact analytical inversion of the integral equation shows that the detuning-independent π/2 pulse amplitude is given by a delta function. The equation also provides a means to calculate numerically approximate π/2 pulses for broadband excitation.

WAVE 시스템에서 미드엠블을 이용한 채널 등화 방식 (Channel Equalization Schemes using Midamble for WAVE Systems)

  • 홍대기;강법주
    • 한국정보통신학회논문지
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    • 제14권10호
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    • pp.2215-2222
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    • 2010
  • 차량 간 통신을 위한 직교 주파수 분할 다중화 (OFDM: Orthogonal Frequency Division Multiplexing)기반 WAVE (Wireless Access for Vehicular Environment) 시스템의 물리계층 표준은 기존에 정지환경을 기반으로 표준화된 IEEE802.11a 무선랜 (WLAN: Wireless Local Area Network)의 물리계층 표준을 따르는 것으로 되어 있다. 따라서 이동환경에 기반한 WAVE 시스템에서 단순한 등화방식을 적용할 경우 빠른 페이딩의 영향으로 인하여 프레임 초기 채널특성과 말기 채널특성의 변화가 초래되어 시스템의 수신 성능이 저하되게 되고, 특히 고차 변조방식에서는 더욱 문제가 된다. 따라서 본 논문에서는 WAVE 시스템의 64-직교진폭변조 (QAM: Quadrature Amplitude Modulation)과 같은 고차 변조에서 채널 등화성능을 향상시키는 방식에 대해 연구하였다. 훈련 심볼을 이용하는 기존의 채널추정방식을 기반으로 하되 WAVE 채널처럼 빠르게 변화하는 채널특성을 추적하기 위해 일정한 주기 마다 미드엠블을 삽입하는 전송구조를 제안하였다. 또한 미드엠블 사이의 심벌들의 채널 변화는 다양한 보간법을 적용한 등화 알고리듬을 제안하였다.

國內 飼育 원숭이의 心電圖에 관한 硏究 (Studies on the Electrocadiogram in Non-human Primates Reared in Korea)

  • 서진석;서지민;이버들;송근호;이수진;김덕환;현병화;신남식
    • 한국임상수의학회지
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    • 제19권2호
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    • pp.132-138
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    • 2002
  • Non-human primates are widely used for experimental animal and raised as companion animal in Korea. To establish the electrocadiogram (ECG) of non-human primates that are domestically raised, the author measured bipolar limb leads and augmented unipolar limb leads, after tiletamine/zolazepam (TZ) injection as sedative agents. The amplitudes of P,Q, R,S and T wave and duration time of P wave, QRS complex, PR and QT interval in each lead of ECG were evaluated in 7 non-human primates at 15 minutes after TZ injection, respectively. The amplitude of P wave in I, II,III, aVR, aVL and aVF leads revealed 0.06$\pm$ 0.05,0.14$\pm$ 0.05, 0.1 $\pm$ 0.05,-0.11 $\pm$ 0.06,-0.04$\pm$ 0.04 and 0.12$\pm$ 0.05 mV respectively. The amplitude of Q wave revealed -0.16$\pm$ 0.15, -0.23$\pm$ 0.18, -0.17$\pm$ 0.13, 0.16$\pm$0.13, 0.04$\pm$ 0.09 and -0.2$\pm$0.13 mV, respectively. The amplitude of R wave revealed 0.56$\pm$0.56, 1.24$\pm$ 0.67, 0.92$\pm$0.33, -0.37$\pm$ 1.14, -0.22$\pm$ 0.47 and 1.12 $\pm$ 0.47 mV, respectively. The amplitude of S wave revealed -0.02$\pm$ 0.08, -0.04$\pm$0.06, -0.06$\pm$0.04, 0.02$\pm$0.04, 0.04$\pm$0.09 and -0.04 $\pm$ 0.06 mV, respectively. The amplitude of T wave revealed -0.01 $\pm$ 0.15,-0.02$\pm$ 0.13, 0.01 $\pm$ 0.08, 0.02$\pm$ 0.12, 0.01 $\pm$ 0.11 and -0.03$\pm$ 0.09 mV, respectively. The duration time of P wave revealed 0.05 $\pm$ 0.01, 0.04$\pm$ 0.01, 0.05$\pm$ 0.02, 0.05 $\pm$ 0.02, 0.04$\pm$ 0.01 and 0.04$\pm$ 0.01 sec, respectively. The duration time of QRS complex revealed 0.05 $\pm$ 0.02,0.05$\pm$ 0.01, 0.05 $\pm$ 0.01, 0.04$\pm$ 0.01, 0.05$\pm$ 0.01 and 0.05 $\pm$ 0.01 sec, respectively. The duration time of PR interval revealed 0.08$\pm$ 0.01, 0.07$\pm$0.01,0.08$\pm$ 0.03, 0.08$\pm$0.01, 0.08$\pm$ 0.01 and 0.08$\pm$0.01 sec, respectively. The duration time of QT interval revealed 0.23$\pm$ 0.06, 0.22$\pm$ 0.05, 0.23 $\pm$ 0.06, 0.23$\pm$ 0.06, 0.24$\pm$ 0.05 and 0.22$\pm$ 0.02 sec, respectively. No significant changes were observed in e amplitude of P and T waves. The amplitude of QRS complex in ketamine group was higher than that of TZ group. However, no significant changes were observed in both intra-group and inter-group. There were no significant changes in the duration time of P wave, QRS complex and PR interval obtained from both groups. Also, the duration time of QT interval in TZ group was significantly longer at 30 min.(P< 0.05) an that of 10 minutes after injection. However, significant difference was not found between two groups. The mean cardiac electric axis in ketamine group tended to decrease until 30 min. after injection and then gradually increase. However, mean cardiac electric axis of TZ group was increased until 30 min. after injection and then decreased. But significant differences were not observed between groups. These results suggest that the ECG pattern after TZ injection to non-human primates reared in korea was established. It was also considered that the injection of ketamine and TZ didn't significantly affect on ECG pattern of the non-human primates.

대진폭 조화 운동을 하는 잠수구에 의한 비선형 조파문제의 시간영역 해석 (Time-Domain Analysis of Nonlinear Wave-Making Problems by a Submerged Sphere Oscillating with Large Amplitude)

  • 김용직;하영록
    • 한국해양공학회지
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    • 제20권6호
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    • pp.67-74
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    • 2006
  • A high-order spectral/boundary-element method is newly adapted as an efficient numerical tool. This method is one of the most efficient numerical methods by which the nonlinear gravity waves can be simulated and hydrodynamic forces also can be calculated in time-domain. In this method, the velocity potential is expressed as the sum of surface potential and body potential. Then, surface potential is solved by using the high-order spectral method and body potential is solved by using the high-order boundary element method. By the combination of these two methods, the wave-making problems by a submerged sphere oscillating with large amplitude under the free~surface are solved in time-domain. Through the example calculations, nonlinear effects on free-surface profiles and hydrodynamic forces are shown and discussed.

Response of square tension leg platforms to hydrodynamic forces

  • Abou-Rayan, A.M.;Seleemah, Ayman A.;El-Gamal, Amr R.
    • Ocean Systems Engineering
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    • 제2권2호
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    • pp.115-135
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    • 2012
  • The very low natural frequencies of tension leg platforms (TLP's) have raised the concern about the significance of the action of hydrodynamic wave forces on the response of such platforms. In this paper, a numerical study using modified Morison equation was carried out in the time domain to investigate the influence of nonlinearities due to hydrodynamic forces and the coupling effect between surge, sway, heave, roll, pitch and yaw degrees of freedom on the dynamic behavior of TLP's. The stiffness of the TLP was derived from a combination of hydrostatic restoring forces and restoring forces due to cables and the nonlinear equations of motion were solved utilizing Newmark's beta integration scheme. The effect of wave characteristics such as wave period and wave height on the response of TLP's was evaluated. Only uni-directional waves in the surge direction was considered in the analysis. It was found that coupling between various degrees of freedom has insignificant effect on the displacement responses. Moreover, for short wave periods (i.e., less than 10 sec.), the surge response consisted of small amplitude oscillations about a displaced position that is significantly dependent on the wave height; whereas for longer wave periods, the surge response showed high amplitude oscillations about its original position. Also, for short wave periods, a higher mode contribution to the pitch response accompanied by period doubling appeared to take place. For long wave periods, (12.5 and 15 sec.), this higher mode contribution vanished after very few cycles.

개에 있어서 실험적 요도폐쇄시의 심전도 변화에 관한 연구 (Studies on Changes of ECG in Dogs with Experimental Obstruction of Urethra)

  • 김추철;김남수;최인혁;이호일
    • 한국임상수의학회지
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    • 제8권1호
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    • pp.93-101
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    • 1991
  • Experimental obstruction of urethra was induced for 66 hours on 5 male dogs to determine the diagnostic value of ECG and blood chemical values. The results obtained in the examination were summarized as follows ; 1. Changes of ECG, blood chemical values and clinical sings were observed from 30 hours after urethral obstruction. 2. In ECG, the peaked and amplitude of T wave were increased remarkably. p wave were decreased, and intervals of PR(Q) and QRS complex were prolonged after urethral obstruction. 3. The levels of BUN, potassium, creatinine in serum after urethral obstruction were increased remarkably and correlation between these levels and the increase of amplitude in T wave were recognized to be significant.

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고립파의 충동에 대한 수치해석 (A Numerical Analysis of the Collision of Solitary Waves)

  • 김도영;배광준;정상권
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2003년도 추계학술대회 논문집
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    • pp.243-249
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    • 2003
  • The head-on collision of two solitary waves are examined using a boundary element method. Attachment, detachment times and alplitudes and maximum run-up times and amplitudes are computed. Consolidation times show local minimum value if two waves are of equal amplitudes are colliding. Attachment times show local maximum value if the amplitudes of two waves are the same. The detachment time show local maximum if two wves are the same. The detachment amplitude show local minimum values if the amplitude e(=a/h) is greater than 0.3.

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