연속파형 Doppler 법에 의한 폐동맥압의 비관혈적 계측

차광수(Kwang Soo Cha),전국진(Kook Jin Chun),신지애(Ji Ae Shin),이동일(Dong Il Lee),이정유(Jung Yoo Lee),이종수(Jong Soo Lee),신영우(Yung Woo Shin),신영기(Yeong Kee Shin),양만석(Man Seok Yang),권형각(Hyong Gak Kwon) 대한내과학회 1991 대한내과학회지 Vol.41 No.5

N/A In order to assess the possibility of noninvasive estimation of pulmonary artery pressure by Doppler echocardiography, pulmonary artery pressures estimated by continuous wave Doppler echocardiography were compared with those measured by cardiac cath-eterization in 10 patients with tricuspid and pulmonary regurgitation. Doppler-determined pressure gradients were estimated from the tricuspid and pulmonary regurgitant flow velocity(V) by means of the simplified Bernoulli equation(ΔP =4v²). The results were as follows: Pressure gradients (PGs) between right ventricle and right atrium at systole measured by Doppler method and catheterization were 58.05±11.67, 59.12±13.78 mmHg, respectively, and correlated well with each other (r=0.95, p<0.01). As for pulmonary arterial systolic pressure (PASP), PGs added by assumed (5 mmHg) right atrial pressure (RAP) and by actual RAP, and catheter-measured PASP were 63.05±11.67, 63.93±11.59, 66.30±12.26mmHg, respectively, and PGs added by assumed RAP and by actual RAP correlated well with catheter-measured PASP, respectively (r=0.97, p<0.01; r=0.98, p<0.01). The PGs between pulmonary artery and right ventricle at end-diastole measured by Doppler method and catheterization were 20.48±4.35, 20.90±4.87, respectively, and correlated well with each other (r=0.97, p<0.01). As for pulmonary arterial diastolic pressure (PADP), the PGs added by assumed (5 mmHg) right ventricular end-diastolic pressure (RVEDP) and by actual RVEDP, and catheter-measured PADP were 25. 48±4.35, 26.38±4.04, 26.80±4.40mmHg, respectively, and PGs added by assumed RVEDP and by actual RVEDP correlated well with catheter-measured PADP, respectively (r=0.96, p<0.01; r=0.96, p<0.01). Doppler-determined PG between the pulmonary artery and right ventricle at early diastole and catheter-measured mean pulmonary arterial pressure were 37.30±6.31, 40.30±5.53mmHg, and correlated well with each other (r=0.81, p<0.01). In conclusion, pulmonary arterial systolic, diastolic pressure and mean pulmonary arterial pressure could be well predicted noninvasively by continuous wave Doppler echocardiography in patients with tricuspid and pulmonary regurgitation,

연속파 Doppler 심초음파 검사에 의한 대동맥 및 폐동맥 혈류량의 측정

주인종(In Jong Joo),김은식(Eun Sik Kim),이문철(Moon Chul Lee),김수경(Soo Kyung Kim),유병희(Byung Hee Yu),이홍순(Hong Soon Lee),이학중(Hak Choong Lee) 대한내과학회 1987 대한내과학회지 Vol.32 No.5

N/A To measure aortic and pulmonary flow, Continuous-Wave Doppler echocardiography was performed in 30 patients who admit to N.M.C, from Mar., 1986 to Sept., 1986. We compared the measurements of aortic and pulmonary flow by CW Doppler echocardiography with those by Fick method of cardiac catheterization to evaluate the accuracy of the measurements by CW Doppler echocardiography. The results were as follows; l) Aortic and pulmonary flow measured by two methods showed a significant correlation of 0.44 (P<0.025) in aortic flow and 0.72 (P<0.005) in pulmonary flow, respectively. 2) Aortic and pulmonary flow measured by CW Doppler echocardiography showed a more significant correlation in the patients with regular heart beat and CI of above 2,2 L/min/m² than in the patients with irregular heart beat and CI of below 2.2 L/min/m² 3) Therefore, a simple & nonivasive Doppler echocardiography was considered as a effective method for measurement of aortic and pulmonary flow.

심 Doppler 와 심도자술에 의한 폐동맥압 및 혈류량 측정 비교

김은식(Eun Sik Kim),이학중(Hak Choong Lee),이홍순(Hong Soon Lee),김종연(Jong Yeun Kim),최덕주(Duck Joo Choi),위상오(Sang Oh Wee),주인종(In Jong Joo) 대한내과학회 1987 대한내과학회지 Vol.33 No.3

N/A A Non-invasive measurement of pulmonary artery pressure and Qp/Qs by continuous-wave Doppler echocardiography was performed on 35 patients with various heart diseases, who had undergone cardiac catheterization, between October 1985 and August 1986 for patients admitted to National Medical Center, and there was intimate correlation between the data of Doppler measurements and modified Picks measurements of pulmonary artery pressure and Qp/Qs. The results were as follows: 1) Pulmonary artery pressure measured by the two methods showed a significantly good correlationship, r=86 and p<005. 2) Twenty one patients had systolic PA pressure less than 25 mmHg and 12 had more than 25 mmHg. Doppler measurement & hemodynamic measurement showed good correlation in both of these groups respectively, with r=56 and p<.01 in pulmonary hypertensive group and r=.83 and p<.005 in pulmonary normotensive group, Fourteen patients had cardiac shunts and 19 had no shunt, and PA pressure in each of theae group showed good correlationship irrespective of shunt with r=0.80 and p<.005 in shunt group and r=.71 and p<.005 in no shunt group. 3) Qp/Qs in both methods of measurement also showed good correlation with r=.79 and p<,05.

Performance of Continuous-wave Coherent Doppler Lidar for Wind Measurement

Shan Jiang,Dongsong Sun,Yuli Han,Fei Han,Anran Zhou,Jun Zheng 한국광학회 2019 Current Optics and Photonics Vol.3 No.5

A system for continuous-wave coherent Doppler lidar (CW lidar), made up of all-fiber structures and a coaxial transmission telescope, was set up for wind measurement in Hefei (31.84 N, 117.27 E), Anhui province of China. The lidar uses a fiber laser as a light source at a wavelength of 1.55 µm, and focuses the laser beam on a location 80 m away from the telescope. Using the CW lidar, radial wind measurement was carried out. Subsequently, the spectra of the atmospheric backscattered signal were analyzed. We tested the noise and obtained the lower limit of wind velocity as 0.721 m/s, through the Rayleigh criterion. According to the number of Doppler peaks in the radial wind spectrum, a classification retrieval algorithm (CRA) combining a Gaussian fitting algorithm and a spectral centroid algorithm is designed to estimate wind velocity. Compared to calibrated pulsed coherent wind lidar, the correlation coefficient for the wind velocity is 0.979, with a standard deviation of 0.103 m/s. The results show that CW lidar offers satisfactory performance and the potential for application in wind measurement.

삼첨판 폐쇄 부전증에서 연속파형 Doppler 심초음파 검사에 의한 우심실 및 폐동맥 수축기압 추정에 관한 연구

김육 ( Kim Yug ),조주영 ( Jo Ju Yeong ),김철현 ( Kim Cheol Hyeon ),김학선 ( Kim Hag Seon ),조영덕 ( Jo Yeong Deog ),김홍수 ( Kim Hong Su ),박노춘 ( Park No Chun ),서세웅 ( Seo Se Ung ),김성구 ( Kim Seong Gu ),권영주 ( Kwon Yeong 대한내과학회 1992 대한내과학회지 Vol.42 No.3

저자들은 16예의 삼첨판 폐쇄 부전증 환자에서 연속파형 Doppler 심초음파로 수축기 역류의 최대속도(PV), 가속시간(AT), 감속시간(DT) 및 감속율(DR)을 계측하여 심도자술에 의한 우심실 및 폐동맥 수축기압과 비교하여 다음과 같은 결과를 얻었다. 1) Doppler 법으로 구한 삼첨판 수축기 역류의 PV는 254.0±71.0 ㎝/sec, PG는 26.9±12.8 mmHg였으며 심도자술로 측정한 우심실과 우심방 사이 수축기 압차는 30±13.9 ㎜Hg였으며 이들 사이에 상관관계는 상관계수 0.84(p<0.001), 0.87(p<0.001) 이었다. 2) Doppler 법으로 구한 삼첨판 수축기 역류의 PV 및 PG와 심도자술로 측정한 우심실압 사이의 상관관계는 0.86(p<0.001), 0.87(p<0.001)의 정상관관계 였으며, 폐동맥압과는 상관계수가 0.82(p<0.001), 0.87(p<0.001) 이었다. 3) 삼첨판 역류의 Doppler signal에서 Deceleration rate는 PV, PG 및 심도자술로 측정한 우심실과 우심방 사이의 압차와는 상관계수 0.90(p<0.001), 0.92(p<0.001), 0.82(p<0.001)의 정상관 관계에 있었다. 이상의 결과 삼첨판 폐쇄 부전증에서 Doppler 법으로 계측한 peak velocity, pressure gradient와 Doppler signal의 deceleration rate로써 우심실 및 폐동맥압을 추정 할 수가 있었다. To determine noninvasive estimation of systolic right ventricular and pulmonary artery pressure by continuous wave Doppler echocardiography. We analyzed continuous wave Doppler echocardiography and cardiac catheterization data in 16 patients with tricuspid regurgitation undergoing right heart catheterization. Peak velocity of systolic tricuspid regurgitation flow by continuous wave Doppler echocardiography was 254.0±71.0 ㎝/sec and calculated pressure gradient between right ventricle and atrium was 26.9±12.8 ㎜Hg. Peak velocity and pressure gradient of systolic tricuspid regurgitation flow in continuous wave Doppler echocardiography significantly correlated with systolic right ventricular pressure (r=0.84 p<0.001, r=0.87 p<0.001) and systolic pulmonary artery pressure (r=0.82 p<0.001, r=0.87 p<0.001) measured by right heart catheterization. Deceleration rate of systolic tricuspid regurgitation flow significantly correlated with peak velocity (r=0.90 p<0.001) and pressure gradient (r=0.92 p<0.001) by continuous wave Doppler echocardiography also significantly correlated with systolic pressure gradient (r=0.82 p<0.001) between right ventricle and right atrium measured by right heart catheterization. In conclusion, we could noninvasively estimate systolic right ventricular and pulmonary artery pressure in the patients with tricuspid regurgitation by analyzing peak velocity, pressure gradient and deceleration rate by continuous wave Doppler echocardiography.

저산소성 폐질환에서 폐동맥압의 비관혈적 측정에 관한 연구

이진구(Jin Goo Lee),인광호(Kwang Ho In),박상면(Sang Myun Park),조재연(Jae Yeon Jho),심재정(Jae Jeong Shim),강경호(Kyung Ho Kang),심완주(Wan Joo Shim),유세화(Se Hwa Yoo) 대한내과학회 1995 대한내과학회지 Vol.49 No.4

N/A Objectives: The presence of pulmonary hypertension in patients with hypoxic lung disease is associated with poor prognosis. Right heart catheterization is the reference method for the diagnosis of pulmonary arterial hypertension but this invasive technique is not always well tolerated in all patients with hypoxic lung disease. There is a need for noninvasive method to allow the accurate estimation of pulmonary arterial pressure in these patients. To find reliable noninvasive methods of measuring pulmonary artery pressure, we evaluated the reliability of continuous wave Doppler echocardiography and gated cardiac blood pool scintigraphy in patents with hypoxic lung disease. Methods: Noninvasive measurements of systolic pulmonary artery pressure by continuous wave Doppler echocardiography and right ventricular ejection fraction by gated cardiac blood pool scintigraphy were compared with systolic pulmonary atery pressure measured by cardiac catheterization in 12 patients with hypoxic lung disease. Results: 1) The systolic pulmonary artery pressures estimated by continuous wave Doppler echocardiography correlated closely with those measured by cardiac catheterization (r=0.88, p<0.01) 2) The right ventricular ejection fraction estimated by gated cardiac blood pool scintigraphy was also correlated well with the systolic pulmonary artery pressure measured by cardiac catheterization (r=0.85, p<0.01). Conclusion: Continuous wave Doppler echocar-diographic estimation of systolic pulmonary artery pressure and gated car diac blood pool scintigraphic estimation of right ventricular ejection pressure are reliable and feasible noninvasive assessment of pulmonary hypertension in patients with hypoxic lung disease.

캡스트럼을 이용한 레이더에서 회전하는 블레이드 검출

송승언,이종훈,고석준 한국정보기술학회 2019 한국정보기술학회논문지 Vol.17 No.1

This paper proposes a cepstrum method in a CW(continuous wave) radar system to detect rotating blades of a drone. Since the size of the drone is much smaller than that of the conventional aircraft, it is difficult to detect by using the conventional detection method. Therefore, a detection method utilizing the Doppler characteristic generated by the rotating blades of the drone has been proposed. There is the STFT(Short Time Fourier Transform) method as a representative detection method using the Doppler characteristic. The STFT method has a disadvantage that a long calculation time is required because of a process of accumulating signals repeatedly. In this paper, to overcome disadvantages of STFT method, the cepstrum method is applied to detect the rotating blades. First, we model the radar cross-section of the rotating blades and then apply the cepstrum method on the received signal of the radar including the Doppler characteristic. Finally, from the simulation results for the performance evaluation, we can see that, in the cepstrum method, it is easily verified the rotating blades of a drone by comparing the threshold and we can find the information of the rotating speed. 본 논문에서는 CW(Continuous Wave) 레이더 시스템에서 캡스트럼을 적용하여 드론의 회전하는 블레이드를 검출하는 방법을 제안한다. 드론은 기존 항공기에 비해 크기가 작아 수신 신호의 전력을 측정하는 방법으로는 검출하기 어려우므로, 드론의 블레이드 회전에 의해 발생한 마이크로 도플러 특성을 활용하는 방법이 사용된다. 마이크로 도플러 특성을 활용하는 대표적인 검출 방법으로는 STFT(Short Time Fourier Transform) 방식이 있다. STFT 방식은 반복적으로 신호를 누적하는 과정이 필요하므로 긴 연산 시간이 요구되는 단점이 있다. 본 논문에서는 STFT의 단점을 극복하기 위해 캡스트럼 방법을 적용하여 회전하는 블레이드를 탐지한다. 우선, 회전하는 블레이드의 레이더 단면적을 모델링하고, 이를 통해 마이크로 도플러 특성을 포함하는 레이더 수신 신호에 캡스트럼을 적용하였다. 최종적으로, 성능 평가를 위해 수행된 시뮬레이션 결과로부터, 캡스트럼 방식은 드론의 존재 여부를 임계치를 적용하여 쉽게 알 수 있으며, 블레이드의 회전 속도에 대한 정보를 얻을 수 있다.

승모판막협착증의 평가방법으로서의 연속파 Doppler 심초음파도와 심도자법의 비교연구

김승관(S . G . Kim),박옥규(O . K . Park),강정채(J . C . Kang),박종춘(J . C . Park),정명호(M . H . Jeong),양승진(S . J . Yang),신순철(S . C . Shin),박상진(S . J . Park) 대한내과학회 1987 대한내과학회지 Vol.33 No.3

N/A In order to evaluate the feasibility of the noninvasive continuous wave Doppler (CWD) echocardiographic technique in evaluating transmitral pressure gradient and the effective mitral valve area, the 17 patients with pure or dominant mitral stenosis were examined by CWD echocardiography and by cardiac catheterization technique. By CWD technique mean and peak transmitral pressure gradient were measured as 9.5±4.0 mmHg, 13.9±4.9mrnHg respectively, and the effective mitral valve area was calculated as 0.62±0.16 cm², while by standard fluid filled catheter system the mean diastolic pressure gradient between the pulmonary capillary wedge position and the left ventricle was measured as 12.2±4.1mmHg, and effective mitral valve area by Gorlin and Gorlin formula was calculated as 0.66±0,39 cm. Each of the mean and peak diastolic pressure gradient by CWD was significantly correlated with the pressure gradient measured by cardiac catheterization technique (r=0.61, r=0,55, p<0.05, p<0.05, repectively). Effective mitral orifice areas measured by either of the technique were well correlated (r=0.73, p<0.02). We concluded that noninvasive CWD technique could be an alternative method to the cardiac catheterization in quantitating the severity of mitral stenosis.

무인기 탐지를 위한 멀티모드 레이다 신호처리 프로세서 설계

이승혁,정용철,정윤호 한국항행학회 2019 韓國航行學會論文誌 Vol.23 No.2

Radar systems are divided into the pulse Doppler (PD) radar and the frequency modulated continuous wave (FMCW) radar depending on the transmission waveform. In particular, the PD radar is advantageous for long-range target detection, and the FMCW radar is suitable for short-range target detection. In this paper, we present design and implementation results for a multi-mode radar signal processor (RSP) that can support both PD and FMCW radar systems to detect unmanned aerial vehicles (UAVs) at short distances as well as long distances. The proposed radar signal processor can be implemented based on Altera Cyclone-IV FPGA with 19,623 logic elements, 9,759 registers, and 25,190,400 memory bits. The logic elements and registers of the proposed radar signal processor are reduced by approximately 43% and 30%, respectively, compared to the sum of logic elements and registers of the conventional PD radar and FMCW radar signal processor. 레이다 시스템은 송신 파형에 따라 크게 PD (pulse Doppler) 레이다와 FMCW (frequency modulated continuous wave) 레이다로 구분되며, 송수신 특성에 따라 PD 레이다는 장거리 표적 검출에 유리한 반면, FMCW 레이다는 단거리 표적 검출에 적합한 특성을 갖는다. 이에 본 논문에서는 중/장거리 뿐 아니라 단거리 무인기 탐지를 위해 PD 레이다 시스템과 FMCW 레이다 시스템을 모두 지원가능한 멀티모드 레이다 신호처리 프로세서 (RSP; radar signal processor)를 제안한다. 제안된 레이다 신호처리 프로세서는 Verilog-HDL을 이용하여 RTL 설계 후, Altera Cyclone-IV FPGA를 이용하여 구현 및 검증 되었다. 구현 결과, 총 19,623개의 logic elements, 9,759개의 register, 그리고 25,190,400의 memory bit로 구현 가능함을 확인하였으며, 기존의 PD 레이다와 FMCW 레이다 신호처리 프로세서를 개별 구현한 경우에 비해 logic elements와 register 요구량이 약 43%와 39% 감소됨을 확인하였다.

멀티모드 레이다 신호처리를 위한 저복잡도 FFT 프로세서 설계

박예림,정용철,정윤호 한국항행학회 2020 韓國航行學會論文誌 Vol.24 No.2

Recently, a multi-mode radar system was designed for efficient operation of unmanned aerial vehicles (UAVs) in various environments, which has the advantage of being able to integrate and utilize methods of the pulse Doppler (PD) radar and the frequency modulated continuous wave (FMCW) radar. For the range detection part of the multi-mode radar signal processor (RSP), the hardware structure using the FFT processor and the IFFT processor is required to be designed in a way that improves efficiency on the area side. In addition, given the radar application environment that requires a variety of distance resolutions, FFT processors need to support variable-length operations. In this paper, the FFT processor and IFFT processor in multi-mode RSP range estimation are designed and proposed as hardware for a single FFT processor that supports variable length operation of 16-1024 points. The proposed FFT processor designed in hardware description language (HDL) and can be implemented with 7,452 logic elements and 5,116 registers. 최근 다양한 환경에서 무인기를 효율적으로 운용하기 위한 목적으로 멀티모드 레이다 시스템이 고안되었으며, 이는 PD (pulse Doppler) 방식과 FMCW (frequency modulated continuous wave) 방식을 통합하여 활용할 수 있다는 장점을 가진다. 멀티모드 레이다 시스템의 하드웨어 구조의 경우 FFT (fast Fourier transform) 프로세서와 IFFT (inverse fast Fourier transform) 프로세서가 필수적이지만, FFT 프로세서는 큰 복잡도를 갖는 구조 중 하나로 FFT 프로세서의 복잡도를 감소시키는 방향으로의 구조 설계가 필요하다. 또한, 다양한 거리 해상도를 요구하는 레이다 응용 환경을 고려했을 때, FFT 프로세서는 가변 길이의 연산을 지원할 필요가 있다. 이에 본 논문에서는 멀티모드 레이다 신호처리 프로세서 거리 추정부의 FFT 프로세서와 IFFT 프로세서를 16~1024 포인트의 가변 길이 연산을 지원하는 단일 FFT 프로세서의 하드웨어로 설계하여 제안한다. 제안된 FFT 프로세서는 MATLAB 기반 알고리즘 설계를 수행한 뒤, 그 결과를 토대로 Verilog-HDL (hardware description language)을 활용하여 RTL (register transfer level) 설계가 수행되었으며, 논리 합성 결과 총 총 7,452개의 logic elements, 5,116개의 registers로 구현 가능함을 확인하였다.