• Journal of Veterinary Clinics
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• v.14 no.2
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• pp.319-337
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• 1997

The electrocardiographic (ECG) parameters in the normal Korean black goat have been measured with a 3-channel Electrocardiograph and computed, analyzed. ECG in 243 black goats were made with the limb leads (I, II, III, aVR, aVL, aVF), that were recorded conduction parameters of wave and interval, and were analyzed as to shape and amplitude of the P and T waves and the components of the QRS complex. Heart rate were recorded by the ECG which were a mean of 106.1$\pm $21.8 beats/min. Average conduction times in the PR, the QRS complex and the QTc interval were recorded 103.9$\pm $34.9 msec., 58.3$\pm $23.2 msec. and 302.6$\pm $67.8 msec., in the P and T wave duration recorded 24.8$\pm $6.4 msec. and 51.7$\pm $10.8 msec. respectively. The shape of wave in each leads were observed various types, and any spacial wave type appeared the highest frequency in each lead that ware shown less than 60%, and these frequent rate and average amplitudes as fallow: 1. In P waver the frequent rate and average amplitudes of the positive type showed in leads I, II and aVL that were 54.8% (93.0$\pm $ 33.2 $\mu $V), 50.5% (90.1$\pm $30.5 $\mu $V) and 41.7% (58.5$\pm $ 31.1 $\mu $V). Average amplitude of the negative type showed the frequent rate of 49.8% in lead aVE which was -77.6$\pm$ 25.2 $\mu $V. Biphasic type in leads III and aVF were 46.1% (108.4 $\mu $V, -90.2 $\mu $V.) and 45.7% (137.4 $\mu $V, -105.4 $\mu $V.), and amplitudes between positive and negative of it were significant difference. 2. The highest amplitudes of the QRS complex in all leads were 534.8$\pm $ 232.3 $\mu $V of lead II. The frequent rate and amplitudes of the R wave type in the I, II, III and aVF were 30.2% (277.8 $\pm $131.3 $\mu $V), 45.1% (393.1$\pm $114.2 $\mu $V), 48.5% (349.3$\pm $178.3 $\mu $V) and 54.9% (334.4$\pm $129.7 $\mu $V), and QS ways type in the lead aVL was 49.5% (359.2$\pm $195.5$\mu $V), and RS and QS wave types in the lead a VR were 43.3% (312.4 $\mu $V, -212.7 $\mu $V.) and 41.1% (399.2$\pm $92.2 $\mu $V), respectively. 3. In T wave, the frequent rata and amplitudes of the positive type in the leads I, II, III and aVF were 44.6% (207.9$\pm $ 97.1 $\mu $V), 41.6% (245.1$\pm $92.1 $\mu $V), 46.9% (189.8$\pm $ 82.7 $\mu $V) and 53.0% (195.4197.8 $\mu $V), and the negative in the lead aVR was 41.2% (-230.7$\pm$ 103.1 $\mu $V), respectively. The positive and negative types in the lead aVe appeared with same frequent rate of 43.2%.4. Frontal plane vectors for P, QRS, and T were found to lie at 38.1$\pm $ 21.5, 142.0$\pm $ 57.2, and 117.2$\pm $ 63.9 degrees, respectively. These results in ECG of goats may be served to the limited purposes as to conduction parameters, arrhythmias except abnormal ECG because of waveforms, amplitudes and electrical axis of it were variability.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.06a
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• pp.263-268
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• 2000

The fretting damage of the contact between Zircaloy-4 and Inconel 600 have Investigated. A fretting wear tester was designed to be suitable for this fretting test. In this study, the number of cycles, slip amplitude and normal load were selected as main factors of fretting wear. As the result of this research the wear volume increased with the increase of loads, slip amplitudes and the number of cycles and was more affected by slip amplitudes rather than by load. According to SEM, stick, partial slip, gross slip were observed on the surface of both specimens and wavy worn surfaces as the typical fretting damage were also Investigated due to accumulation of plastic flow.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.54.1-54.1
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• 2015

We report results of investigation of amplitude calibration for very long baseline interferometry (VLBI) observations with Korean VLBI Network (KVN). Amplitude correction factors are estimated based on comparison of KVN observations at 22 GHz correlated by Daejeon hardware correlator and DiFX software correlator in Korea Astronomy and Space Science Institue (KASI) with Very Long Baseline Array (VLBA) observations at 22 GHz by DiFX software correlator in National Radio Astronomy Observatory (NRAO). We used the observations for compact radio sources, 3C 454.3 and NRAO 512 which are almost unresolved for baselines in a range of 350-477 km. VLBA visibility data of the sources observed with similar baselines as KVN are selected, fringe-fitted, calibrated, and compared in their amplitudes. We found that visibility amplitudes of KVN observations should be corrected by factors of 1.14 and 1.40 when correlated by DiFX and Daejeon correlators, respectively. These correction factors are attributed to the combination of two steps of 2-bit quantization in KVN observing systems and characteristics of Daejeon correlator.

• Structural Engineering and Mechanics
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• v.75 no.3
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• pp.377-387
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• 2020

Modern long-span floor system typically possesses low damping and low natural frequency, presenting a potential vibration sensitivity problem induced by human activities. Field test and numerical analysis methods are available to study this kind of problems, but would be inconvenient for design engineers. This paper proposes a simplified method to determine the acceleration amplitudes of long-span floor system subjected to walking or running load, which can be carried out manually. To theoretically analyze the acceleration response, the floor system is simplified as an anisotropic rectangular plate and the mode decomposition method is used. To facilitate the calculation of acceleration amplitude a_P, a coefficient α_wmn or α_Rmn is introduced, with the former depending on the geometry and support condition of floor system and the latter on the contact duration t_R and natural frequency. The proposed simplified method is easy for practical use and gives safe structural designs.

• Journal of The Korean Astronomical Society
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• v.37 no.5
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• pp.553-556
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• 2004

We present a new model for the generation of magnetic fields on large scales occurring at the end of cosmological reionisation. The inhomogeneous radiation provided by luminous sources and the fluctuations in the matter density field are the major ingredients of the model. More specifically, differential radiation pressure acting on ions and electrons gives rise to electric currents which induce magnetic fields on large scales. We show that on protogalactic scales, this process is highly efficient, leading to magnetic field amplitudes of the order of $10^{-1l}$ Gauss. While remaining of negligible dynamical impact, those amplitudes are million times higher than those obtained in usual astrophysical magnetogenesis models. Finally, we derive the relation between the power spectrum of the generated field and the one of the matter density fluctuations. We show in particular that magnetic fields are preferably created on large (galactic or cluster) scales. Small scale magnetic fields are strongly disfavoured, which further makes the process we propose an ideal candidate to explain the origin of magnetic fields in large scale structures.

• Journal of electromagnetic engineering and science
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• v.8 no.2
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• pp.59-63
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• 2008

The adaptive symbol selection scheme(ASSS) is popular in reducing peak to average power ratio(PAPR) for orthogonal frequency division multiplexing(OFDM) signals. The probability density function(pdf) of the samples' amplitudes of the adaptively selected OFDM signal without over-sampling has been considered to be approximately equal to the Rayleigh pdf. In this paper, we derive a more precise pdf which shows the relationship between the probability distribution of the samples' amplitudes and the number of the candidate symbols for ASSS. Using the newly derived pdf in the theoretical analysis, more accurate calculation results can be obtained.

• 한국지구물리탐사학회:학술대회논문집
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• 2005.09a
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• pp.3-9
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• 2005

In order to obtain more reliable data for the information on the ground, a new site Investigation method is proposed, in which seismic waves (S-waves) generated by the Swedish Ram Sounding Test (SRS) are used. It is indicated that the energy transferred from the hammer to the rod in SRS's is much more stable, compared to SPT's. A series of SRS with measurements of seismic waves at the ground surface were carried out to clarify the characteristics of seismic wave propagation in the ground. As the results of comparison between seismic S-wave amplitudes and $N_d$ (blow count for 20 cm penetration in SRS), it was found that amplitudes of S-waves generated by SRS correlate well with $N_d$. The amplitude of the S-wave is thought to be more adequate parameter for the soil strength and rigidity than $N_d$.

• Journal of Korean Institute of Industrial Engineers
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• v.12 no.2
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• pp.1-11
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• 1986

This study is concerned on computerized analysis of COG, torques and EMG amplitudes in weight-lifting motion. The results show that; (1) torques on major joints show a rather consistent relationship with respect to the sequence of four distinct motions in weight-lifting, (2) analysis of EMG amplitudes is a sensitive measure of both athlete's skill and his potential capability, and (3) range of COG variations can be used as indicator of motion stability, existence of undesirable posture, and target muscle for intensive training. A computerized routine, which includes analyses on COG, EMG and torque, is a scientific tool for coaching athletes. In addition, an Expert System which includes CAD routine was developed in order to promote better understanding for athletes and coaches.

• Journal of Mechanical Science and Technology
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• v.17 no.11
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• pp.1650-1658
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• 2003

This paper deals with a novel shunt circuit, which is capable of suppressing multimode vibration amplitudes by using a pair of piezoceramic patches. In order to describe the characteristic behaviors of a piezoelectric damper connected with a series and a parallel resistor-negative capacitor branch circuit, the stiffness ratio and loss factor with respect to the non-dimensional frequency are considered. The mechanism of the shunt damper is also described by considering a shunt voltage constrained by shunt impedance. To obtain a guideline model of the piezo/beam system with a negative capacitive shunting, the governing equations of motion are derived through the Hamilton's principle and a piezo sensor equation as well as a shunt-damping matrix is developed. The theoretical analysis shows that the piezo/beam system combined with a series and a parallel resistor-negative capacitor branch circuit developed in this study can significantly reduce the multiple-mode vibration amplitudes over the whole structural frequency range.

• Journal of Astronomy and Space Sciences
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• v.27 no.4
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• pp.279-288
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• 2010

To study properties of the pulsation in the infrared emission for long period variables, we have collected and analyzed the infrared observational data at M band for 12 OH/IR stars. We present the light curves using the data that cover about 30 years including recent observations of ISO and Spitzer. We use Marquardt-Levenberg algorithm to determine the pulsation periods and amplitudes and compare them with previous results of infrared and radio investigations. Generally, the newly determined pulsation parameters show much less errors because of the larger database. We find that the relationship between the pulsation period and amplitudes at M band is fairly well fitted with a simple linear equation in a wide period range. For OH 42.3-0.1, we find some evidences that the object could be a post-asymptotic giant branch star.