• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.12
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• pp.1275-1283
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• 2014

Characteristics of PCM(Pulse Code Modulation) waveform are suitable for target tracking. Especially in terms of dwell time, it is desirable to detect and track a moving target with the single PCM waveform for a MFR(Multi-Function Radar) which carries out multiple tasks. General PCM waveform processing includes Doppler filter bank caused by the characteristics of ambiguity function, to detect target and estimate Doppler frequency, which induces hardware burden and computational complexity. We propose a ML(Maximum Likelihood) based Doppler estimator for a PCM waveform, which is the closed form suboptimal solution and computationally efficient to estimate Doppler frequency and detect a moving target.

• The Journal of Korean Medicine
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• v.29 no.2
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• pp.60-70
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• 2008

Objectives: The aim of the present investigation was to determine whether the finger photoplethysmography (PPG) of the young will become analogous to those of the old when the PPG harmonic components in the young decrease. Methods: The PPG was measured in 46 old men (21 males and 25 females) over the age of 60 years and 10 young men (5 males and 5 females). We acquired the representative pulse waveform of old men by averaging the PPG waveforms measured in the old men. after the PPG harmonic components in the young men were diminished with notch filtering, we compared the representative pulse waveform of old men and those of the young men. Results: The PPG waveform of the young males became analogous to the representative pulse waveform of the old as the PPG harmonic components in the young were diminished with notch filtering. Especially after the second harmonic component in the young was diminished with notch filtering, increase of the Pearson's correlation coefficient was prominent. On the other hand, the Pearson's correlation coefficient between the PPG waveforms of the young females and that of the old deceased after the second harmonic component diminished in the young. Conclusions: Decrease of the second harmonic component may be a precondition of typical age-related change of the pulse waveform in the healthy male.

• Journal of Magnetics
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• v.14 no.3
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• pp.132-136
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• 2009

This study investigated the radial pulse waveform obtained by a medical pulsimeter sensor. A pulse-sensing part array consisting of multiple Hall devices was located over a skin-contacting part with a hard magnetic material. The periodic movement of the magnetic material of the skin-contacting part affected the magnetic field in the pulse-sensing part array and was detected by multiple Hall devices. The analysis of a radial pulse waveform that is measured noninvasively by detecting the changes of the magnetic field can be used to develop a new diagnostic algorithm of oriental medical apparatus.

• Proceedings of the IEEK Conference
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• 2000.06b
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• pp.48-51
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• 2000

We proposed the new driving waveform which has changed the waveform of sustain division to improve luminous efficiency in plasma display panel. This sustain waveform is to add the ramp to the rectangular waveform, resulting in self-erasing discharge in the falling edge region. The proposed waveform has improved the luminous efficiency of 30％ even in low driving frequency(25kHz), whereas the conventional driving waveform using the self-erasing discharge can improve the luminous efficiency only in high driving frequency( >150kHz). Front the results of this paper, we hope that the variety study on frequency and duty ratio, ramp waveform will increase the luminous efficiency.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.511-514
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• 2004

ADS(Address Display period Separation) driving method has been considered to be the most appropriate driving technique for AC PDPs. However when the ADS driving method is applied to the high-resolution AC PDP, the required long addressing time often becomes a problem. In this paper, we present a new waveform for reducing the addressing time and for the stable addressing discharge. In this new waveform, a wall charge acceleration pulse is applied to the common electrode right after 80us scan time. In this way, the charge generated by the addressing discharge is accelerated to the electrodes. Experiments using the wall charge acceleration pulse showed that we could stably address an AC PDP with the scan pulses having pulse width of 1 us

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.2118-2120
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• 1998

Recently the automatization and the robotization of the arc welding industry is promoted and also the improvement of the welding quality and the work efficiency is required strongly. In this paper, special welding current waveform control algorithm is developed for less spatter and improvement of welding performance in the high speed and low arc voltage range. And the output control and the short circuit waveform control to the varition of the welding is studied by appling the algorithm to the power source for pulse arc welding.

• Proceedings of the KSMRM Conference
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• 1999.11a
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• pp.87-87
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• 1999

• Journal of Electrical Engineering and Technology
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• v.5 no.3
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• pp.497-502
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• 2010

In this paper, the O-mode ultrashort-pulse reflectometry (USPR) millimeter-wave signals that propagate into the plasma and cover a frequency bandwidth of 33-158 GHz are examined numerically using MATLAB. Two important processes are involved in the computation: the propagation of the USPR impulse signal through a waveguide and the frequency up-conversion using millimeter-wave mixers. These mixers are limited to intermediate frequency signals that are less than 500 mV; thus, it is necessary to disperse the impulse signal into a chirped waveform using the waveguide. The stationary phase method is utilized to derive a closed-form formula for a chirped waveform under the assumption that the USPR impulse is Gaussian. In the process of frequency up-conversion, the chirped waveform is mixed with the mixer LO signal, and the lower frequency components of the RF signal are removed using high pass filters.

• Journal of Communications and Networks
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• v.10 no.4
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• pp.451-454
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• 2008

Ultra-wideband (UWB) radios have attracted great interest for their potential application in short-range high-data-rate wireless communications. High received signal to noise ratio and compliance with the Federal Communications Commissions (FCC) spectral mask call for judicious design of UWB pulse shapers. In this paper, even and odd order derivatives of Gaussian pulse are used respectively as base waveforms to produce two synthesized pulses. Our method can realize high efficiency of spectral utilization in terms of normalized effective signal power (NESP). The waveform design problem can be converted into linear programming problem, which can be efficiently solved. The waveform based on even order derivatives is orthogonal to the one based on odd order derivatives.

• Journal of Biomedical Engineering Research
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• v.28 no.6
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• pp.721-726
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• 2007

The study relates to achievement and analysis of 3-dimensional spatial pulse wave archived by a spatially arterial pulse diagnostic apparatus (SAPDA), wherein a pulse sensing part array consists of multiple hall devices and is located over a skin contacting part which consists of a magnetic material. When a radially arterial pulse is transferred to the magnetic material, which is contacted skin that results in changes in a magnetic field of the lower part of the pulse sensing part array, the changes in a magnetic field can be detected by the commercial Hall semiconductor device of the pulse sensing part array. Finally, according to development of SAPDA, the 3-dimensionally arterial pulse waveform can be measured noninvasively by detecting the changes of the magnetic field.