1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118)最新文献_第6页

Theoretical evaluation of a 50 MHz split aperture linear phased array 50mhz分孔径线性相控阵的理论评价

1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118) Pub Date : 1997-10-05 DOI: 10.1109/ULTSYM.1997.663317

J. Talman, G. Lockwood

引用次数: 3

Comparison between time reversal focusing in absorbing medium and inverse filtering 吸收介质时间反转聚焦与反滤波的比较

1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118) Pub Date : 1997-10-05 DOI: 10.1109/ULTSYM.1997.663348

M. Tanter, J. Thomas, M. Fink

引用次数: 6

Stacked composite piezoelectric materials for 1.5-D arrays 用于1.5维阵列的堆叠复合压电材料

1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118) Pub Date : 1997-10-05 DOI: 10.1109/ULTSYM.1997.661731

C. Oakley, B. Pazol, D. Powell, M.R. LaBree, K. M. Gabriel, L. Koornneef, M. Callahan, G. Wojcik

{"title":"Stacked composite piezoelectric materials for 1.5-D arrays","authors":"C. Oakley, B. Pazol, D. Powell, M.R. LaBree, K. M. Gabriel, L. Koornneef, M. Callahan, G. Wojcik","doi":"10.1109/ULTSYM.1997.661731","DOIUrl":"https://doi.org/10.1109/ULTSYM.1997.661731","url":null,"abstract":"Composite piezoelectric materials with a 1-3 connectivity are almost ideal for transducer applications where the width-to-thickness aspect ratio of individual elements is in the range of about 0.7 to 10 (the range required for most 1.5-D array applications). The high anisotropy of the composite enhances coupling in the thickness mode but reduces the coupling and damps vibrations in the lateral direction. One major drawback of these composites is that the reduced volume fraction of ceramic results in elements with a low capacitance and high electrical impedance making the small elements difficult to drive. A solution to this drawback is to stack the composite material in n layers and connect the layers in parallel to achieve the n/sup 2/ reduction in electrical impedance. This paper presents a method for making stacked composite material and using them in 1.5-D arrays. This method consists of stacking 2-2 composites with the strips running in the scan-plane of the proposed array and creating the 1-3 structure during array construction by using standard dicing and subdicing techniques of the acoustic stack. Measured results from stacked composites made by both the dice-and-fill and injection mold-and-fill methods are presented and compared. The consequences of misalignment are shown and analyzed. The cost implications for both dice-and-fill and injection mold-and-fill methods are discussed.","PeriodicalId":6369,"journal":{"name":"1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118)","volume":"61 1","pages":"923-926 vol.2"},"PeriodicalIF":0.0,"publicationDate":"1997-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81125841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 13

Multiple access to SAW sensors using matched filter properties 使用匹配的滤波器属性对SAW传感器进行多次访问

1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118) Pub Date : 1997-10-05 DOI: 10.1109/ULTSYM.1997.663035

G. Ostermayer, A. Pohl, L. Reindl, F. Seifert

引用次数: 15

Adaptive heterodyne photorefractive interferometer for ultrasound detection: optimization and application 用于超声检测的自适应外差光折变干涉仪:优化与应用

1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118) Pub Date : 1997-10-05 DOI: 10.1109/ULTSYM.1997.663096

R. K. Ing, B.F. Pouet, S. Krishnaswamy, D. Royer

引用次数: 1

Surfing the SAW: visualizing the oscillation of Au(111) surface atoms 在SAW上冲浪:可视化Au(111)表面原子的振荡

1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118) Pub Date : 1997-10-05 DOI: 10.1109/ULTSYM.1997.663073

T. Hesjedal, E. Chilla, H.-J. Frohlich

{"title":"Surfing the SAW: visualizing the oscillation of Au(111) surface atoms","authors":"T. Hesjedal, E. Chilla, H.-J. Frohlich","doi":"10.1109/ULTSYM.1997.663073","DOIUrl":"https://doi.org/10.1109/ULTSYM.1997.663073","url":null,"abstract":"In this paper we report the observation of surface acoustic waves using a scanning tunneling microscope (STM). As the STM control electronics have a bandwidth limit in the kHz range, SAWs at typical frequencies of MHz to GHz cause a loss of contrast which can be clearly seen on an atomic scale. In order to access the amplitude and phase of a SAW, we introduced a heterodyning type STM, the scanning acoustic tunneling microscope (SATM). Contrary to the STM technique, the SATM measures snapshots of the state of oscillation. On the nanometer scale, two contributions to the phase and amplitude contrast are discussed. First, the SAWs phase delay gives a mainly linear dependence on the distance of the source. Second, the atomic oscillation trajectories within the SAW lead to a signal contribution that is made up of the shape of the oscillation trajectory and the local topography. On an atomic scale where the influence of the phase delay on the contrast can be neglected the oscillation trajectories of single surface atoms are studied. Finally, the atomically resolved phase and amplitude images are compared to simulated data.","PeriodicalId":6369,"journal":{"name":"1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118)","volume":"33 1","pages":"511-514 vol.1"},"PeriodicalIF":0.0,"publicationDate":"1997-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78651031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Texture based adaptive clustering algorithm for 3D breast lesion segmentation 基于纹理的乳腺三维病灶分割自适应聚类算法

1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118) Pub Date : 1997-10-05 DOI: 10.1109/ULTSYM.1997.661836

D. Boukerroui, O. Basset, A. Baskurt, A. Hernandez, N. Guérin, G. Giménez

引用次数: 7

Volumetric blood flow velocity measurement with multigate pulsed Doppler system using single-channel RF sampling 采用单通道射频采样的多门脉冲多普勒系统的体积血流速度测量

1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118) Pub Date : 1997-10-05 DOI: 10.1109/ULTSYM.1997.661806

C. Lim, J. Remeniéras, A. Roncin, M. Berson

{"title":"Volumetric blood flow velocity measurement with multigate pulsed Doppler system using single-channel RF sampling","authors":"C. Lim, J. Remeniéras, A. Roncin, M. Berson","doi":"10.1109/ULTSYM.1997.661806","DOIUrl":"https://doi.org/10.1109/ULTSYM.1997.661806","url":null,"abstract":"Presents the performances of a new Doppler system using single channel RF sampling. The conventional quadrature method in Doppler imaging system has to use a minimum of two identical parallel demodulation channels to reconstruct the multigate analytic Doppler signal. However, this system suffers from hardware complexity and the problem of unbalance (gain and phase) between the channels. In order to reduce these problems, the authors realize a multigate pulsed Doppler system using undersampling on a single channel. It requires a sampling frequency at 4f/sub a/ and a 12 bits A/D converter. The proposed \"Single-Channel RF Sampling\" method aims to decrease the required sampling frequency proportionally to 4f/sub a//(2k+1). To show the influence of the factor k on the measurements, the authors compare the velocity profiles obtained in vitro and in vivo for different intersequence delay times (k=0 to 10). The authors have used a 4 MHz center frequency transducer. For experiments in vitro, on a phantom Doppler system, axial and volumetric velocity profiles in the vessel have been computed according to factor k and have been compared. The influence of the angle between the ultrasonic beam and the flow axis direction, and of the fluid viscosity on the velocity profiles obtained for different values of k factor is presented. For experiments in vivo on the carotid, the authors used a data acquisition system with a sampling frequency of 500 kHz and a dynamic range of 12 bits. The authors compare axial velocity profiles in systolic and diastolic phases obtained for different single channel RF sampling factors.","PeriodicalId":6369,"journal":{"name":"1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118)","volume":"1 1","pages":"1255-1258 vol.2"},"PeriodicalIF":0.0,"publicationDate":"1997-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79886860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Noise robust two-dimensional blind deconvolution of ultrasound images 噪声鲁棒超声图像二维盲反卷积

1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118) Pub Date : 1997-10-05 DOI: 10.1109/ULTSYM.1997.661853

T. Taxt, J. Strand

引用次数: 2

Fine elasticity imaging utilizing the refined iterative rf-echo phase matching algorithm 利用改进迭代射频回波相位匹配算法的精细弹性成像

1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118) Pub Date : 1997-10-05 DOI: 10.1109/ULTSYM.1997.661865

C. Sumi, K. Nakayama, M. Kubota

{"title":"Fine elasticity imaging utilizing the refined iterative rf-echo phase matching algorithm","authors":"C. Sumi, K. Nakayama, M. Kubota","doi":"10.1109/ULTSYM.1997.661865","DOIUrl":"https://doi.org/10.1109/ULTSYM.1997.661865","url":null,"abstract":"It is quite remarkable that the pathological state of living soft tissue highly correlates with quasi-static mechanical properties, i.e., particularly elasticity. With such a fact in mind, we previously developed \"the iterative 2D rf-echo phase matching method\" that determines the 2D displacement vector field generated in in vivo soft tissue during acquisition of two successive rf-echo data frames. That is, since this displacement measurement allows an accurate estimate of the resultant strain distributions to be obtained, we can stably quantify the tissue elasticity by determining the relative shear modulus distribution. Toward the finer elasticity imaging, we recently improved the previous displacement measurement method such that better phase matching can be realized. That is, we novelly incorporate an effective mechanism into the previous one: the local region size is made suitably smaller during the iterative phase matching. This leads to improvement of the quality of the finally obtained elasticity image. The effectiveness was verified through simulation, and an experiment on in vitro pork and in vivo breast tissues.","PeriodicalId":6369,"journal":{"name":"1997 IEEE Ultrasonics Symposium Proceedings. An International Symposium (Cat. No.97CH36118)","volume":"29 1","pages":"1521-1526 vol.2"},"PeriodicalIF":0.0,"publicationDate":"1997-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90319391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4