• Korean Journal of Artificial Intelligence
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• v.6 no.1
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• pp.11-15
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• 2018

The purpose of this study is to develop a pulsatile drowsiness detection system that can compensate the limitations of existing camera - based or breathing pressure sensor based Drowsiness driving prevention systems. A heart rate sensor mounted on the driver's finger and an alarm system that sounds when drowsiness is detected. The heart rate sensor was used to measure pulse changes in the wrist, and an alarm system based on the Arduino, which works in conjunction with the laptop, generates an audible alarm in the event of drowsiness. In this paper, we assume that the pulse rate of the drowsy state is 60 ~ 65 times / minute, which is the middle between the awake state and the sleep state. As a result of the experiment, the alarm sounded when the driver's pulse rate was in the drowsy pulse rate range. Based on these experiments, the drowsiness detection system was able to detect the drowsiness of the driver successfully in real time. A more effective drowsiness prevention system can be developed in the future by incorporating the results of the present study on a pulse-based drowsiness prevention system in an existing drowsiness prevention system.

• Journal of Biomedical Engineering Research
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• v.27 no.3
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• pp.89-93
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• 2006

A simple algorithm that can be used to estimate a healthy person's blood pressure using pulse transit time is proposed in this paper. Fifty healthy students participated in the experiment that was conducted in line with the study. The subjects were asked to exercise on several exercise levels using a bicycle ergometer. Their blood pressures during the succeeding rest period were measured. A simple method was proposed to illustrate the relationship between blood pressure and pulse transit time. The systolic blood pressures as well as the heights and weights of the subjects were regarded as the proper parameters, and a second-order regression curve was produced to estimate the subjects' blood pressures. The mean error of estimation was less than 10 mmHg, which was the mean error of manual measurement. Although our estimation model is so simple, it can be used to estimate continuous blood pressure measurement for bicycle ergometer exercise. The electrocardiograms, photoplethysmograms, and blood pressures, however, could not be measured simultaneously As such, their estimation may be slightly different from the results taken from simultaneous measurements.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.4
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• pp.1209-1223
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• 2022

Blood pressure is one of the key physiological parameters for determining human health, and can prove whether human cardiovascular function is healthy or not. In general, what we call blood pressure refers to arterial blood pressure. Blood pressure fluctuates greatly and, due to the influence of various factors, even varies with each heartbeat. Therefore, achievement of continuous blood pressure measurement is particularly important for more accurate diagnosis. It is difficult to achieve long-term continuous blood pressure monitoring with traditional measurement methods due to the continuous wear of measuring instruments. On the other hand, radar technology is not easily affected by environmental factors and is capable of strong penetration. In this study, by using machine learning, tried to develop a linear blood pressure prediction model using data from a public database. The radar sensor evaluates the measured object, obtains the pulse waveform data, calculates the pulse transmission time, and obtains the blood pressure data through linear model regression analysis. Confirm its availability to facilitate follow-up research, such as integrating other sensors, collecting temperature, heartbeat, respiratory pulse and other data, and seeking medical treatment in time in case of abnormalities.

• Journal of Acupuncture Research
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• v.32 no.2
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• pp.169-185
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• 2015

Objectives : The purpose of this study is to find the effects of Sa-am liver tonifying and sedating acupuncture on radial pulse. Methods : Sixty healthy people were divided into a liver tonifying acupuncture(LTA) group, liver sedating acupuncture(LSA) group, and control group. The LTA group and LSA group received acupuncture for 20 minutes with a supine position. The Control group took a rest without receiving acupuncture. Radial pulse was measured by three dimensional pulse imaging system(DMP-3000) at four different time points (before, right after, 30 minutes after, and 60 minutes after acupuncture). We compared the three groups and figure out determined the parameters which significantly changed after acupuncture treatment. Results : 1. Pulse period, T1/T, T4/T, (T-T4)/T, T4/(T-T4), T5/T significantly changed after acupuncture. 2. H4, pulse area, systolic pulse area, diastolic pulse area, radial augmentation index(RAI), and pulse power volume / min significantly changed after acupuncture. 3. Frequency of Fourier components, ratio of frequencies of Fourier components, magnitude of Fourier components, and ratio of magnitudes of Fourier components significantly changed after acupuncture. Conclusions : LTA and LSA have an effect on the radial pulse parameters. Further studies on radial pulse change using Sa-Am acupuncture are needed.

• Korean Journal of Oriental Medicine
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• v.17 no.3
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• pp.87-96
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• 2011

Objectives : The study on the affected factor of the pulse wave is important in the pulse wave part. The purpose of this study is to secure the objective data of pulse-wave parameter on the food intakes affected the radial pulse-wave. Methods : The study was carried out healthy adult men. We researched the blood circulation index and the changes of the pulse factor according to 'before meal', 'right after meal', '30 minute after meal', '1 hour after meal' and '2 hours after meal'. We analyzed the changes according the time schedule. And analyzed the difference between 'before meal' and 'after meal'on the pulse-wave parameter. Results : The results were as follows. 1. HR, ECO and ECI were showed the highest increase 'after meal' and the significant decrease in '2 hours after meal' with 'before meal' degree. 2. In the pulse energy, 'left hand average pulse energy' was showed the highest increase 'after meal', and 'right hand average pulse energy' and 'right Quan(關)' were showed the highest increase in '30 minute after meal'. 3. h1 of '6 part of left and right hand'(Chon-Quan-Chuk, 寸關尺) was showed the significant difference statistically in 'left Chuk' and 'right Quan'. 4. T was showed the highest 'before meal' and the lowest after meal in '6 part of left and right' (Chon-Quan-Chuk, 寸關尺). 5. RAI was showed the highest 'before meal' in '6 part of left and right'(Chon-Quan-Chuk 寸關尺). Conclusions : From the about results, the food intakes was considered important factor of pulse formation. On the factor affected the pulse, we considered that continuous study needs for the future.

• Journal of Welding and Joining
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• v.33 no.6
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• pp.21-26
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• 2015

Recently, application of UHSS(Ultra High Strength Steels) whose tensile strength is over 1000MPa to car body structure are growing due to great needs for light weighting and improved crash worthiness. However, their poor weldability is one of obstacles to expand selecting to car body. In this study, effect of Phosphorus contents on resistance spot weldability of high elongation DP980 steel whose Si content is over 1% was investigated. The cross tension strength (CTS) was decreased showing partial interface fracture as Phosphorus content increase because of solidification segregation of Phosphorus. In order to improve resistance spot weldability by modification of welding condition, in-situ post-weld heating pulse was introduced after main pulse. The optimum cooling time between main and post pulse and post-pulse current condtion were determined through FEM welding simulation and DOE tests. The CTS was increased about 1.5 time showing plug fracture. The decrease of Phosphorus segregation was found to be a major reason for weld ductility and CTS improvement.

• Nuclear Engineering and Technology
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• v.54 no.12
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• pp.4715-4721
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• 2022

A comprehensive approach for modeling the pulse height spectra of gamma-ray detectors from passing radioactive cloud in a case of accident at NPP has been developed. It involves modeling the transport of radionuclides in the atmosphere using Lagrangian stochastic model, WRF meteorological processor with an ARW core and GFS data to obtain spatial distribution of radionuclides in the air at a given moment of time. Applying representation of the cloud as superposition of elementary sources of gamma radiation the pulse height spectra are calculated based on data on flux density from point isotropic sources and detector response function. The proposed approach allows us to obtain time-dependent spectra for any complex radionuclide composition of the release. The results of modeling the pulse height spectra of the scintillator detector NaI(Tl) Ø63×63 mm for a hypothetical severe accident at a NPP are presented.

• Proceedings of the IEEK Conference
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• 2000.06a
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• pp.271-274
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• 2000

In this paper, the distortion of an electrical pulse with rise/fall time resulting from dispersion and reflection as it propagates along a tapered microstrip line is investigated, and the delay time and distortion rate with respect to input and load impedances are analyzed on triangular and exponential tapered lines and analyzed the influence of the reflection and frequency dispersion on the distorted voltage wave in the tapered lines. The observed overshoot in front of the distorted wave is caused due to the frequency dispersion and the sustained tail of that comes from the reflection in the tapered line.

• Journal of the Korean Society of Safety
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• v.16 no.4
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• pp.7-13
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• 2001

Wire electrical discharge machining experiments in conducted to investigate characteristics of acoustic emission (AE) and electrical discharge energy due to current peak (I$_{p}$), pulse on time($\tau$/on/). The AE signals are obtained with a sensor attached to workpiece side. Machining states are identified with scanning electron microscopy and residual stress analyzer. It is demonstrated that the residual stress provide reliable informations about the machining states. Moreover, machining states can be detected successfully using both the residual stress and AE count rate.e.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.5
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• pp.516-524
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• 1997

The propagation properties of various pulse signal types(square pulse, Gaussian pulse, trapezoid pulse, RF pulse) on coupled microstrip lines are investigated. Numerical integration technique which has its accuracy and is easily simulated, is used to obtain the time domain response of pulse signals. Frequency-dependent characteristics of coupled microstrip line is obtained using Jansen's approximate equation. The propagation properties of pulse signal on coupled microstrip lines is analyzed regarding to its geometric structure (relative permittivity ${varepsilon}_r$ substrate height h, strip width w of the microstrip line) and pulse width ${\tau}$ of signal pulse. The simulation results show that space between two lines is very significant parameter in pulse distortion in comparison of any other parameters. The results of this paper are compatible to the trade-off determination of relative permittivity, substrate height, strip width and pulse width of signal pulse when a design of MIC and MMIC is necessary.