• 한국지구물리탐사학회:학술대회논문집
• /
• 2006.06a
• /
• pp.225-231
• /
• 2006

As a study of efficient velocity analysis in sonic log, several preexisting techniques have been adopted to the sonic data taken from model borehole in Kangwon National University, and the results were compared. For the data taken from monopole source, Slowness-Time Coherence method which is a common technique for nondispersive wave was used. For the data taken from dipole source, conventional STC and Tang's method(Tang et al., 1995) were used. From the good matches in the P and Stoneley wave velocities, we could confirm the effectiveness of STC computation. We also could find that shear velocity obtained from Tang's method were exactly matched with shear velocity obtained from monopole source, and that the velocity were within the range of S wave velocity values obtained from conventional STC application to dispersive flexural waves.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.21 no.6
• /
• pp.1506-1512
• /
• 2007

In order to investigate the totale yield, the content of soluble polysaccharide and the others of FEW extract from the yeast fermentated Ganoderma lucidium by supersonic method, the yeast strain was inoculated after pretreatment and subsequently followed fermentation and supersonic extract. The main construction of the extract method is composed of the main glucose and together with the xylose, fucose, galactose and mannose. Results show that because of the generated lactic acid and ethanol, pH value of extract decreases and the safety as well as the preservation is improved. The extract yield, the total soluble polysaccharide, SOD-like activity, cytotoxic effect and growth inhibitory effect against cancer cell line are much higher in FE method than RE method, especially FEW3 extracts fermented during 24hrs. It is concluded that yeast fermentation makes the extract yield increase because of the cell disintegration, the useful ingredients of the germ body, the metabolic products, the insoluble ingredients due to the generation of ethanol, and the cell fragmentation caused by the supersonic waves vibration. Content of generated ethanol, total soluble polysaccharide and extract yield all increase during the fermentation time from 24 to 72 hours and the optimum fermentation condition is at $27^{\circ}C$ for 72 hours. The bitter taste and smell of the Ganoderma lucidium extract is diminished, fragrant-bitter taste and smell is generated so that the whole functional quality is improved.

• Journal of Ocean Engineering and Technology
• /
• v.27 no.4
• /
• pp.76-82
• /
• 2013

Motion reduction of an offshore structure at resonant frequency is essential for avoiding critical damage to the topside and mooring system. A damping plate has a distinct advantage in reducing the motion of a floating structure by increasing the added mass and the damping coefficient. In this study, the heave motion responses of a circular cylinder with an impermeable and a permeable damping plate attached at the bottom of the cylinder were investigated thru a model test. The viscous damping coefficients for various combinations of porosity were obtained from a free-decay test by determining the ratio between any pair of successive amplitudes. Maximum energy dissipation occurred at a porous plate with a porosity P = 0.1008. Experimental results for regular and irregular waves were compared with an analytical solution by Cho (2011). The measured heave RAO and spectrum reasonably followed the trends of the predicted values. A significant motion reduction at resonant frequency was pronounced and the heaving-motion energy calculated by the integration of the area under the heave motion spectrum was reduced by more than 75% by the damping plate. However, additional energy dissipation by eddies of strong vorticity and flow separation inside a porous damping plate was not found in the present experiments.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.4
• /
• pp.945-952
• /
• 2013

The R wave of QRS complex is the most prominent feature in ECG because of its specific shape; therefore it is taken as a reference in ECG feature extraction. But R wave detection suffers from the fact that frequency bands of the noise/other components such as P/T waves overlap with that of QRS complex. ECG signal processing must consider efficiency for hardware and software resources available in processing for miniaturization and low power. In other words, the design of algorithm that exactly detects QRS region using minimal computation by analyzing the person's physical condition and/or environment is needed. Therefore, efficient QRS detection based on SOM(Subtractive Operation Method) is presented in this paper. For this purpose, we detected R wave through the preprocessing method using morphological filter, empirical threshold, and subtractive signal. Also, we applied dynamic backward searching method for efficient detection. The performance of R wave detection is evaluated by using MIT-BIH arrhythmia database. The achieved scores indicate the average of 99.41% in R wave detection.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.9 no.3
• /
• pp.141-147
• /
• 2006

A newly designed floating breakwater made of Polyethylene with considering the introduction of new material for being harmony with environment and stability of the floater is developed for a marine ranching. In this study, the new concept in which incident wave dissipates its energy due to the vortex shedding by passing through the pipes and sheets is selected for wave breaking mechanism. Model experiment in order to te st its capability is performed for the regular and irregular waves in ocean engineering basin. Good capability to break the incident wave within the 6 seconds of period and 1 m of height is shown. Breaking efficiency for long period wave is not so good in regular and irregular wave. The results of this study will contribute to the design and construction of the floating breakwater.

• Proceedings of the KOSOMBE Conference
• /
• v.1997 no.11
• /
• pp.403-406
• /
• 1997

Electrogastrogaphy(EGG) is the technique by which gastric myoelectrical activity is recorded noninvasively, from electrodes on the abdominal skin. Despite many attempts made over the decades, the clinical application of the EGG signal has not improved to the identification of waveform characteristics using comparison of EGG signal to be detected other EGG system. Cutaneous measurements of EGG are yet to be standardized in methods of detection and analysis. This may be responsible in part for some of the variability in the results. Thus, we develope EGG system composed of amplifiers, analysis methods, patient database or standardization. we introduce configurations of EGG system and their functions. Several important EGG parameters are introduced, including the dominant frequency and power of the EGG, the relative, period EGG-dominant frequency and power, the instability coefficient of EGG-dominant frequency and power, standard deviation, the percentage of running spectrum activity of gastric slow waves.

• Journal of Oriental Neuropsychiatry
• /
• v.19 no.2
• /
• pp.165-193
• /
• 2008

Objective: The ECG which used for this paper, is analysis result from alogrisms of arrythmia, and we have studied that how we could certain Cold(寒)type or Heat(熱) type and that Deficiency(虛) type or Excess(實)type of organs from various special diseases, and we obtained like these results. Method & Conclusion: 1. we depend on our examination about Pulse(脈) because we can't discriminate arrythmia using ECG analysis instruments. 2. We obtained that Cold(寒) type diseases had wave that prolonged above normal baseline and ST wave which had downward aptitude. 3. We obtained that Heat(熱) type diseases had the fibrillation which had shortend wave that compare to normal and had downward aptitude or negative aptitude. 4. We obtained that Respiratory system (肺) diseases had wave that is within normal or is short of normal range and had much fluctuation in potential difference or trans on P wave. 5. The character of EKG which presented about diseases of gastric systems is prolonged above narmal range of wave, and the ECG had represented mixed wave with Heat(熱) type when accompany inflammatory in gastric system. 6. The wave of Blood Stasis(瘀血) type had upward aptitude of QRS wave, and the wave of anemia or blood loss type(少血) had downward aptitude of QRS wave, the wave which had both Cold(寒)) and Heat (熱) represented mixed waves. 7. The Knotted Pulse(結脈) and Intermittent Pulse(代脈)is corresponded with sinus brady cardia, and the Swift Pulsle(疾脈) is corresponded with fibrillation. 8. We pay attention to the relations of formations about pressures pulse from formations of EMD( electromechanical dissociation ). Result : From these results, we will have to study about ECG which using in tests of change of Parkinsons disease.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2010.08a
• /
• pp.243-243
• /
• 2010

Low-temperature grown (LTG) InGaAs epilayers were grown by MBE technique for studying a correlation between terahertz (THz) emission and the intrinsic defects. The 1.2-um-thick Be-compensated LTG-InGaAs epilayers were prepared on SI-InP:Fe substrate at $200-250^{\circ}C$, and subsequently in-situ annealed under As environment at $550^{\circ}C$ for 5-30 minutes. The carrier concentration/mobility and the crystalline structure were analyzed by the Hall effect and the x-ray diffraction (XRD), respectively, and the carrier lifetime were determined by the fs time-resolved pump-probe spectroscopy. THz generation from LTG-InGaAs was carried out by a Ti-sapphire laser (800 nm) of a pulse width of 190 fs at a repetition of 76 MHz. Figure shows the spectral amplitude of generated waves in the THz region. As the growth temperature of epilayer increases, the amplitude is enhanced. However, two samples grown at $200^{\circ}C$, as-grown and annealed, show almost no difference in the spectral amplitude. This suggests that the growth temperature is critical in the formation of defect states involved in THz emission. We are now investigating the correlations between the XRD band attributed to defects, the Hall parameter, and the spectral amplitude of generated THz wave.

• The Bulletin of The Korean Astronomical Society
• /
• v.36 no.2
• /
• pp.141.1-141.1
• /
• 2011

New CCD BVR light curves of BD And are presented. Our light curves with nearly equal depths for both primary and secondary eclipses show well-defined photometric waves outside eclipse for all of BVR bandpasses. The orbital period is greatly revised as $0.^d92580519$ which is twice longer than that known previously. Sixteen timings from our observations and thirteen ones from the SuperWASP measurements were calculated. All available timings over 76 years, including ours, were analyzed to figure out the dynamical behavior of the system. It was found that the recent CCD O-C residuals varied in a cyclical way with a period of $9.^y18$ and a semi-amplitude of $0.^d0046$. The secondary period of $9.^y18$ is the most shortest one among those which have been ever found in the short period RS CVn binary stars. The periodic variation most likely arises from the light-travel time effect due to a low-mass ($m_3{\sim}0.88\;M_{\odot}$) tertiary companion moving in an orbit with an large eccentricity ($e_3$=0.70) and a low inclination ($i_3{\sim}28^{\circ}$). The Applegate mechanism could not operate properly in both components because the model parameters require too much large luminosity changes of ${\Delta}L/L_{p,s}$ > 10. The new light curves were synthesized using the 2003 version of Wilson-Divinney code. It was found useful to model two huge spots on the surface of the hotter star and a third-light in order to minimize the residuals from the observations. Astronomical basic parameters were deduced from our photometric solution.

• Journal of Sensor Science and Technology
• /
• v.21 no.2
• /
• pp.135-143
• /
• 2012

Arterial stiffness is causing the serious problems for human who is suffered from hypertension and metabolic syndrome. So it is important that measure the arterial stiffness for early prevention. Many researches point out that pulse wave velocity(PWV) is the reliable and simple method to predict arterial stiffness. In this paper, we developed the sensing parts that detect the pulse wave and ECG by using piezoelectric film and conductive textile with elastic band. Our system could detect 3ch pulse wave and ECG. Simultaneously, our algorithm extracts the features for calculating the delays among pulse waves. The delays are the significant parameter to estimate PWV, thus we design the experiment for evaluating the performance of our sensing parts. The reference is PP-1000(HanByul Meditech, Korea) that is good for performance evaluation. As a result, the start point of the pulse wave was the most reliable feature for comparing with PP-1000(r=0.691, P=0.00). The results between two operators showed that there is only a slight difference in the reproducibility of the devices. In conclusion, we assume that the suggested sensor could be more comfortable and faithful method for arterial stiffness.