In view of the discrete characteristics of biological tissue, doublet mechanics has demonstrated its advantages in the mathematic description of tissue in terms of high frequency （〉 10 MHz） ultrasound. In this pape...In view of the discrete characteristics of biological tissue, doublet mechanics has demonstrated its advantages in the mathematic description of tissue in terms of high frequency （〉 10 MHz） ultrasound. In this paper, we take human breast biopsies as an example to study the influence of the internodal distance, a microscope parameter in biological tissue in doublet mechanics, on the sound velocity and attenuation by numerical simulation. The internodal distance causes the sound velocity and attenuation in biological tissue to change with the increase of frequency. The magnitude of such a change in pathological tissue is distinctly different from that in normal tissue, which can be used to differentiate pathological tissue from normal tissue and can depict the diseased tissue structure by obtaining the sound and attenuation distribution in the sample at high ultrasound frequency. A comparison of sensitivity between the doublet model and conventional continuum model is made, indicating that this is a new method of characterizing ultrasound tissue and diagnosing diseases.展开更多
B&K 4195人工耳原有等效电路模型的仿真结果在3 k Hz以上频段与实测相差较大,无法满足精度要求。通过有限元仿真和声阻抗转移理论的对比,对突变截面结构提出了附加质量概念,从而完善了腔管结构在较大尺寸和较高频段下的等效电路模...B&K 4195人工耳原有等效电路模型的仿真结果在3 k Hz以上频段与实测相差较大,无法满足精度要求。通过有限元仿真和声阻抗转移理论的对比,对突变截面结构提出了附加质量概念,从而完善了腔管结构在较大尺寸和较高频段下的等效电路模型。根据此方法修正了人工耳耳廓部分的等效电路模型,使仿真与实测在6 k Hz前的频段内吻合较好。展开更多
基金Project supported by the National Basic Research Program of China(Grant Nos.2012CB921504 and 2011CB707902)the National Natural Science Foundation of China(Grant No.11274166)+3 种基金the Fundamental Research Funds for the Central Universities,China(Grant Nos.1113020403 and 1101020402)the State Key Laboratory of Acoustics,Chinese Academy of Sciences(Grant No.SKLA201401)the China Postdoctoral Science Foundation(Grant No.2013M531313)the Priority Academic Program Development of Jiangsu Provincial Higher Education Institutions and Scientific Research Foundation for Returned Overseas Chinese Scholars,State Education Ministry,and the Project of Interdisciplinary Center of Nanjing University,China(Grant No.NJUDC2012004)
文摘In view of the discrete characteristics of biological tissue, doublet mechanics has demonstrated its advantages in the mathematic description of tissue in terms of high frequency （〉 10 MHz） ultrasound. In this paper, we take human breast biopsies as an example to study the influence of the internodal distance, a microscope parameter in biological tissue in doublet mechanics, on the sound velocity and attenuation by numerical simulation. The internodal distance causes the sound velocity and attenuation in biological tissue to change with the increase of frequency. The magnitude of such a change in pathological tissue is distinctly different from that in normal tissue, which can be used to differentiate pathological tissue from normal tissue and can depict the diseased tissue structure by obtaining the sound and attenuation distribution in the sample at high ultrasound frequency. A comparison of sensitivity between the doublet model and conventional continuum model is made, indicating that this is a new method of characterizing ultrasound tissue and diagnosing diseases.
文摘B&K 4195人工耳原有等效电路模型的仿真结果在3 k Hz以上频段与实测相差较大,无法满足精度要求。通过有限元仿真和声阻抗转移理论的对比,对突变截面结构提出了附加质量概念,从而完善了腔管结构在较大尺寸和较高频段下的等效电路模型。根据此方法修正了人工耳耳廓部分的等效电路模型,使仿真与实测在6 k Hz前的频段内吻合较好。
