CAJ | 학술논문

采用超声导波评价长骨骨质状况已是近几年来的一个研究热点.在应用时频表征方法处理导波实验信号的研究中,选择交叉项抑制效果好的时频表征核函数直接影响到导波信号的分离和提取.提出将Zhao-Atlas-Marks分布(ZAMD)应用于分析长骨中的导波信号,同时与重排光滑伪维格纳维利分布(RSPWVD)的分析结果进行比较,并用图像处理中的骨架求取算法,估计导波平均频率慢度曲线.分析结果表明,ZAMD可较好地去除交叉项干扰,得到较准确的超声导波频散特性曲线,说明ZAMD是分析长骨中超声导波信号的一种较好方法.
채용초성도파평개장골골질상황이시근궤년래적일개연구열점.재응용시빈표정방법처리도파실험신호적연구중,선택교차항억제효과호적시빈표정핵함수직접영향도도파신호적분리화제취.제출장Zhao-Atlas-Marks분포(ZAMD)응용우분석장골중적도파신호,동시여중배광활위유격납유리분포(RSPWVD)적분석결과진행비교,병용도상처리중적골가구취산법,고계도파평균빈솔만도곡선.분석결과표명,ZAMD가교호지거제교차항간우,득도교준학적초성도파빈산특성곡선,설명ZAMD시분석장골중초성도파신호적일충교호방법.
During the last years, there has been a considerable interest of using quantitative ultrasonic guided waves (GW) to evaluate the long bone quality. Time-frequency representation method is employed as a classical one for GW signal processing. Different time-frequency representations have different kernels which directly affect the separation and feature extraction. This paper employed the Zhao-Atlas-Marks distribution (ZAMD) to analyze the GW signal excited in the long bone, and comparing with reassigned smoothed-pseudo Wigner-Ville distribution (RSPWVD). The results showed that ZAMD can remove the cross-terms effectively. Furthermore, the average GW frequency slowness curves, which are helpful for getting the quantitative dispersion characteristics of long bone, were obtained by an image processing method. In general, it is proved that ZAMD, which can smooth out the cross-terms and get the GW dispersion characteristic curves effectively, is a good one of the time-frequency methods for the GW signal processing.