• Title/Summary/Keyword: DOPPLER

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Improvement of Processing Speed of the Doppler Filter in a Low Power Radar (저 출력 레이더의 도플러필터의 처리속도 개선)

  • Park, Jeong-Ho;Jeong, Hong
    • Proceedings of the IEEK Conference
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    • 2001.06d
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    • pp.167-170
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    • 2001
  • A low power pulse Doppler radar should integrate a large number of data to provide a required maximum detectable distance. Doppler filter needs a window that has good out-of-bard rejection level to maintain high dynamic range. From these facts, we can apply decimation and presumming to increase the speed of Doppler processing. This Paper investigates the efficiencies of several decimation methods and the loss of presumming. And I propose a method to increase processing speed but to maintain the maximum detectable distance.

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Relationship between UV-induced MED and Perfusion Value Assessed by Laser Doppler Perfusion Imager (Laser Doppler Perfusion Imager (LDPI)로 측정한 자외선 조사부위의 혈류량과 최소 홍반량(MED)과의 상관관계)

  • Kim, Nam-Soo;Lee, Kyung-Hoon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.31 no.3 s.52
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    • pp.259-263
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    • 2005
  • The aim of the present study is to evaluate relationship between UV-induced MED and perfusion value assessed by Laser Doppler Perfusion Imager. In this study, A increasing linear relationship is seen between perfusion and dose (p<0.05). The dose-response curve show a steep slope in the case of lower MED values group after MED point, For higher MED group, increase with a gentle slope.

In Vivo Doppler-Based Measurement of Bending Vibration Velocity in Liver Vibrated by Lo7v Frequency Signal (초음파 Doppler법에 의한 비침투적인 생체조직의 진동속도 계측)

  • 박무훈;장윤석
    • Journal of Biomedical Engineering Research
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    • v.18 no.4
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    • pp.407-412
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    • 1997
  • In this paper, we present a new method to diagnose the characteristics of the soft tissue, especially a liver. In order to diagnose the characteristics of a liver, it is necessary to evaluate the propagation delay time and propagation velocity of bending vibration In a liver. For this purpose, we measure the propagation velocity of bending vibration in a liver for low frequency forced vibration using a standard ultrasonic Doppler diagnosis equipment. We have carried out preliminary experiments by using an ultrasonic probe of 3.5MHz and obtained some results. This new measurement method developed here can be applied to new research and medical fields for acoustic non-invasive diagnosis of soft tissue.

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Three-Dimensional Flow in an Aortic Bifurcation Model: Comparison of In Vitro Experiments and Numerical Simulation (대동맥 분기관 모델 내 삼차원 유동: In vitro 실험과 수치해석의 비교)

  • Kim, Young-H.;Seo, Sang-H.;Ryu, Sang-S.
    • Proceedings of the KOSOMBE Conference
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    • v.1995 no.05
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    • pp.15-18
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    • 1995
  • Three-dimensional steady and pulsatile flow experiments and numerical simulations have conducted to investigate the flow characteristics in the aortic bifurcation model. In vitro velocity measurements were made using both laser Doppler anemometry and pulsed Doppler ultrasound velocimetry. In this study, flow phenomena in the aortic bifurcation model are discussed extensively and the numerical results are compared with experimental results.

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Rain Rate Estimation Process Using Doppler Spectrum of UHF Wind Profiler Radar

  • Kitichai Visessiri;Chaiwat Somboonlarp;Anuchit Waisontia;Lee, Nipha laruji;Narong Hemmakon
    • Proceedings of the IEEK Conference
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    • 2002.07c
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    • pp.1575-1577
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    • 2002
  • In this research we propose a method far rain rate estimation by using Doppler spectrum's data of wind profiler. The Doppler spectrum is used to calculate the wind velocity and wind direction. But in this research uses the parameters from Doppler spectrum, it calculates the rain rate. The rain rate estimation in this method will be compared to the obtained rain rate from the surface rain gauge. Two equipments are installed in the same area. The correlation coefficient between rain rate measuring method is 0.65.

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Venous Occlusion Detected by Caregiver with Implantable Doppler in a Buried Free Flap

  • Hur, Su Won;Kim, Tae Gon;Lee, Jun Ho;Chung, Kyu Jin;Kim, Yong-Ha
    • Archives of Craniofacial Surgery
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    • v.15 no.3
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    • pp.121-124
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    • 2014
  • The use of the implantable Doppler device eases the burden of free flap monitoring, and allows caregivers to notify healthcare personnel of a potential vascular event. A 24-year-old female patient underwent anterolateral thigh adipofascial flap surgery to provide a buried flap on the left temporal area for a depressed and infected skull wound. The author was able to salvage the flap from two venous occlusions, which was made possible by early notifications from the caregiver who reported changes in the Doppler signal.

Design of WiFi-AP Doppler Detection based Wireless Security Services (WiFi-AP 도플러 검파 기반의 무선 보안서비스 설계)

  • Kang, Min-Goo
    • Journal of Satellite, Information and Communications
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    • v.9 no.4
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    • pp.16-19
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    • 2014
  • In this paper, the beacon signals of WiFi doppler frequency detection based WiFi-AP was designed with the subcarrier between a transmitter and a receiver of WLAN(wireless LAN). We can use such signals to identify human moving as an antenna array and tracking of RF beam. This wireless security services with the combination of WiFi doppler frequency and adaptive beacon time signal was proposed for wireless detection and motion based services.

Laser doppler velocimeter using the self-mixing effect of a $CO_2$ laser (산란광의 되먹임을 이용한 $CO_2$ 레이저 도플러 속도 측정)

  • 최종운;김용평;김윤명
    • Korean Journal of Optics and Photonics
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    • v.7 no.2
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    • pp.157-161
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    • 1996
  • A simple laser Doppler velocimeter(LDV) using a $CO_2$ laser with its self-mixing effect has been developed. We measured the laser power which was modulated by Doppler frequency, when monochromatic laser light was focused to a moving target. The Doppler-shifted frequency was controlled by changing rotating speed of the turntable or the cosine of the angle between the direction of the laser beam and that of the rotating velocity.

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Benchmark Calculations of Lattice Codes for the Doppler Coefficient of MOX Fuel

  • Shin, Ho-Cheol;Bae, Sung-Man;Kim, Yong-Bae;Lee, Sang-Hee
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05a
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    • pp.46-51
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    • 1996
  • In this study we calculate the infite multiplication factors ($k_{\infty}$) and the Doppler temperature coefficients (DTC) of two mixed-oxide (MOX) fuel rods with different plutonium contents by using PHOENIX-P, HELIOS and CASMO-3 codes. The results were compared against the reference values obtained by MCNP-3A continuous-energy Monte Carlo code. The purpose of this study is to benchmark the accuracy of these lattice codes. The PHOENIX-P's Doppler coefficients calculated were in good agreement with the MCNP results within the Monte-Carlo uncertainty band which is in the order of $\pm$ 10% for the Doppler coefficients..

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Doppler Signal Analysis for Low Velocity Measurement (저 유속 측정에서의 도플러 해석 기법)

  • Lee, Jonggil
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.10a
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    • pp.956-957
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    • 2014
  • In a fluid velocity measurement radar, the velocity information can be extracted from Doppler spectrum estimates of the return signal. However, the Doppler frequency ranges are too low for the case of low velocity profile measurements resulting in the serious effects in the velocity measurement. Therefore, the improved method is analyzed to overcome this problem.

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