2019 International Congress on Ultrasonics最新文献

{"title":"High intensity focused ultrasound power measurement based on cross-spectral density technique","authors":"Guangzhen Xing, Minda Dai, Ping Yang, Longbiao He, Yuebing Wang","doi":"10.1121/2.0001127","DOIUrl":"https://doi.org/10.1121/2.0001127","url":null,"abstract":"The purpose of this work was to develop a dependable and safe method of measurement of HIFU fields without mechanical damage to the sensor. The metrology for the applied high ultrasonic power of HIFU has vital importance for patient safety, however it still remains a challenge. Among the measurement methods, radiation force balance and calorimetric buoyancy are frequently used; however, the heating transmission of the target and drift of the balance induce high uncertainties. In this paper, an alternative method is described. Instead of using a balance, the method relies on scanning the ultrasound field in two parallel planes using a hydrophone before the focusing area, which avoids the hydrophone being damaged by high intensities. In addition to the ultrasonic power, the instantaneous intensity can also be determined. In HIFU fields, nonlinear effects will inevitably occur and therefore hydrophone deconvolution is used to account for the pressure pulse distortion caused by its non-uniform sensitivity. The principles and theory behind the cross-spectral density technique is outlined and validation experiments are presented. The uncertainties of the technique proposed are on the order of 10% for intensity measurements. These value maybe further reduced by improving the accuracy of hydrophone sensitivity.","PeriodicalId":330911,"journal":{"name":"2019 International Congress on Ultrasonics","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122404980","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}

{"title":"Noncontact inspection using identifying each resonance frequency of defect and laser Doppler vibrometer by spatial spectral entropy","authors":"K. Sugimoto, T. Sugimoto, N. Utagawa, Chitose Kuroda","doi":"10.1121/2.0001107","DOIUrl":"https://doi.org/10.1121/2.0001107","url":null,"abstract":"In our noncontact acoustic inspection method, we have studied a noncontact non-destructive method to detect and visualize internal defects (depth to 10 cm) of composite material (especially concrete) from a long distance (5 – 33 m). The target surface is excited by aerial plane sound waves by a long-range acoustic device (LRAD) and the vibration velocity distribution on the two-dimensional lattice points is measured with a scanning laser Doppler vibrometer (SLDV). Conventionally, after signal processing, internal defects were detected by combining acoustical feature quantities (vibrational energy ratio and spectral entropy) [1,2]. This time, we propose spatial spectral entropy (SSE). SSE can automatically detect resonance frequencies of internal defects, and at the same time, can detect resonance frequencies of a high sensitivity SLDV. Using SSE analysis, internal defect detection and clear defect imaging were achieved for an actual concrete structure.","PeriodicalId":330911,"journal":{"name":"2019 International Congress on Ultrasonics","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124740355","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}

{"title":"Ultrasonic temperature monitoring in tissue phantoms by locally resolved measurement of longitudinal and transverse wave speed","authors":"M. Wolf, L. Timmermann, A. Juhrig, K. Rath, Emanuel Leipner, F. Krujatz, E. Kühnicke","doi":"10.1121/2.0001076","DOIUrl":"https://doi.org/10.1121/2.0001076","url":null,"abstract":"To optimize hyperthermia in cancer therapy, a monitoring of temperature and tissue properties inside the tumor and in the surrounding tissue is necessary during the therapy. As the use of computed tomography (CT) or Magnetic resonance imaging (MRI) during the operation is very expensive, ultrasonic measurements are a very good alternative.This contribution presents a method to measure the longitudinal wave speed spatially resolved by analyzing the ultrasonic signals reflected from small scatterers in a tissue phantom. Thus no additional reflectors at known positions are necessary. The measurements are carried out using a 10 MHz prefocused annular-array and the recorded signals are focused synthetically. Measurements are carried out on a tissue phantom synthesized by polyacrylamide. Algae are added to gain natural scattering in the phantom. The capabilities of the method are demonstrated by monitoring the temperature distribution during local heating of a phantom. Additionally, the reachable accuracy as well as reachable temporal and local resolution are discussed. Due to increasing heat supply denaturation occurs, a second measurand is necessary. Therefore, the transverse wave speed is determined by transient elastography.To optimize hyperthermia in cancer therapy, a monitoring of temperature and tissue properties inside the tumor and in the surrounding tissue is necessary during the therapy. As the use of computed tomography (CT) or Magnetic resonance imaging (MRI) during the operation is very expensive, ultrasonic measurements are a very good alternative.This contribution presents a method to measure the longitudinal wave speed spatially resolved by analyzing the ultrasonic signals reflected from small scatterers in a tissue phantom. Thus no additional reflectors at known positions are necessary. The measurements are carried out using a 10 MHz prefocused annular-array and the recorded signals are focused synthetically. Measurements are carried out on a tissue phantom synthesized by polyacrylamide. Algae are added to gain natural scattering in the phantom. The capabilities of the method are demonstrated by monitoring the temperature distribution during local heating of a phantom. Additionally, the reachable accuracy as we...","PeriodicalId":330911,"journal":{"name":"2019 International Congress on Ultrasonics","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127819615","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}

{"title":"Noncontact acoustic inspection of outer wall by acoustic irradiation induced vibration from UAV equipped with sound source","authors":"T. Sugimoto, K. Sugimoto, I. Uechi, N. Utagawa, Chitose Kuroda","doi":"10.1121/2.0001078","DOIUrl":"https://doi.org/10.1121/2.0001078","url":null,"abstract":"The noncontact acoustic inspection method is an excellent method capable of detecting defects at the same level as a hammering test from a long distance. However, there is a disadvantage that it becomes difficult to generate the same flexural resonance as the hammering test when the angle of the measurement target surface viewed from the sound source increases. Fortunately, when a sound source itself is mounted on an unmanned aerial vehicle (UAV) which is becoming popular in recent years, it becomes possible to make the sound source position directly face the measurement target surface, and this problem of angle dependence is expected to be resolved. Therefore, in this research, we investigated the outer wall inspection by noncontact acoustic inspection method using sound source mounted type UAV and the outer wall tile specimen. From this result, we confirmed that it is possible to detect delamination defects of outer wall tiles by our proposed method utilizing deflection resonance even using compact sound sources that can be mounted on UAV. Therefore, it is expected that it will be possible to carry out long-distance measurement up to the measurable limit of LDV.","PeriodicalId":330911,"journal":{"name":"2019 International Congress on Ultrasonics","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128315446","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}

{"title":"Using acoustic holography to characterize absorbing layers","authors":"D. Nikolaev, S. Tsysar, A. Krendeleva, O. Sapozhnikov, V. Khokhlova","doi":"10.1121/2.0001120","DOIUrl":"https://doi.org/10.1121/2.0001120","url":null,"abstract":"In most applications of ultrasound, it is important to know acoustic characteristics of the propagation medium such as the speed of sound and absorption coefficient within a certain frequency range. By definition, these parameters refer to the propagation of a plane wave [1]. Most methods for measuring such characteristics use flat receiving and transmitting emitters [2] and for many applications such an approach is not accurate enough.The current work is devoted to the experimental study of acoustic parameters of the propagation medium using holography-based method. Soft rubber material has been characterized. It was shown that the proposed method allows to accurately measure the speed of sound and absorption coefficient in a wide frequency range.","PeriodicalId":330911,"journal":{"name":"2019 International Congress on Ultrasonics","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122904231","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}

{"title":"Probing Corium in severe nuclear accident experiments: Development of acoustic techniques resisting very high temperatures","authors":"M. Cavaro, K. Paumel, N. Chikhi, P. Fouquart, J. Delacroix, R. L. Tellier, V. Bouyer","doi":"10.1121/2.0001075","DOIUrl":"https://doi.org/10.1121/2.0001075","url":null,"abstract":"Since the Fukushima-Daiichi accident, severe accident research has been reconsidered from another perspective. In the case of a severe accident in a nuclear reactor, the core can melt to form corium, a complex mixture of molten fuel and structural materials. In order to improve reactor safety and mitigate the accident on site, it is important to understand the behaviour of corium in the configurations. In the context of in-vessel retention (IVR) studies, the scientific community has limited knowledge of immiscible phase stratification phenomenon. This knowledge could be further developed thanks to experiments with dedicated online instrumentation to follow the metal relocation transient occurring below the oxide phase and the stratification inversion kinetics. This instrumentation has to resist an aggressive liquid and high temperatures (1700–3000°C). The study of an ultrasonic technique, based on time-of-flight measurements, using a refractory material waveguide is in progress. This paper describes the feasibility approach used and the resulting choice of waveguide (able to withstand high temperatures, no interaction with steel, and transmission of the acoustic wave in the waveguide and at the waveguide/ steel interface), the choice of ultrasonic transducer, the numerical simulations, and the results of preliminary experiments performed at high temperature (>1500°C).","PeriodicalId":330911,"journal":{"name":"2019 International Congress on Ultrasonics","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122041382","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}

{"title":"Direct detection of gravitating dark particles navitens by nonlinear effects in crystal vibrations and by particles track","authors":"I. Ostrovskii","doi":"10.1121/2.0001129","DOIUrl":"https://doi.org/10.1121/2.0001129","url":null,"abstract":"The previously unknown energetic dark particles (EDP) of (4±1.5)10E15 eV mass-energy from the Milky Way center (CMW) are directly detected. Particles are named Navitens. The vibrations in piezoelectric crystals are theoretically calculated along with nonlinear effects due to frictional influence of EDP producing changes in the spectra of vibrations under orientation of crystallographic axes toward CMW. The mechanism of EDP-crystal interaction may be associated with the gravitational influence of EDP and their quantum properties, such as matter waves. The EDP energy density is 0.3 – 0.7 (GeV/ cm cub.) near Earth, which agrees with the existing astrophysical bounds for dark matter in the solar neighborhood. The uncertainties are due to different times of observations. The EDP can transfer their momenta-energy to a media of propagation. The influence of Navitens on vibrating atoms are detected from 10 different samples during several years. The micro-void tracks of EDP-particles are also observed in the vibrating plates of fused quarts and silica glasses. It happens because EDP may decay inside solid media. The existence of EDP-Naviten particles agrees with recent detection of ∼10E15 eV energy neutrinos from the CMW region and rare observations of the cosmic rays of so-called knee-energy.","PeriodicalId":330911,"journal":{"name":"2019 International Congress on Ultrasonics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128232080","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}

{"title":"Assessment of a breast cancer response to neoadjuvant chemotherapy using backscatter ultrasound statistics","authors":"Z. Klimonda, P. Karwat, K. Dobruch-Sobczak, H. Piotrzkowska-Wróblewska, J. Litniewski","doi":"10.1121/2.0001104","DOIUrl":"https://doi.org/10.1121/2.0001104","url":null,"abstract":"Neoadjuvant chemotherapy (NAC) is used in breast cancer treatment. A correct assessment of a cancer response to the therapy is necessary to decide whether to continue the treatment, change the drug or refer the patient to surgery to remove the tumor. The aim of this study was to assess the tumor response to the therapy, based on backscattered ultrasound statistics. Radio-frequency (RF) images were acquired from 30 tumors being treated using NAC. After the NAC therapy, the tumors were excised and examined histopathologically. As a part of the ultrasound data analysis, an experienced physician specified a tumor area on each image. Then, a probability density function (PDF) of the signal amplitude within the tumor was estimated, as well as tumor size (TS). Next, a difference between the PDF corresponding to the data acquired before the therapy and the PDFs corresponding to the successive NAC courses was measured for each tumor using the Kullback-Leibler symmetrized divergence (KLSD). A statistical analysis was performed to assess the ability of the KLSD and TS, obtained in the subsequent NAC rounds, to predict the final tumor response to the treatment. Results suggest that such parameters can be useful in the NAC monitoring.Neoadjuvant chemotherapy (NAC) is used in breast cancer treatment. A correct assessment of a cancer response to the therapy is necessary to decide whether to continue the treatment, change the drug or refer the patient to surgery to remove the tumor. The aim of this study was to assess the tumor response to the therapy, based on backscattered ultrasound statistics. Radio-frequency (RF) images were acquired from 30 tumors being treated using NAC. After the NAC therapy, the tumors were excised and examined histopathologically. As a part of the ultrasound data analysis, an experienced physician specified a tumor area on each image. Then, a probability density function (PDF) of the signal amplitude within the tumor was estimated, as well as tumor size (TS). Next, a difference between the PDF corresponding to the data acquired before the therapy and the PDFs corresponding to the successive NAC courses was measured for each tumor using the Kullback-Leibler symmetrized divergence (KLSD). A statistical analysis w...","PeriodicalId":330911,"journal":{"name":"2019 International Congress on Ultrasonics","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128689276","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}

{"title":"Dynamics of constrained bubbles: symmetry approach","authors":"A. Maksimov","doi":"10.1121/2.0001112","DOIUrl":"https://doi.org/10.1121/2.0001112","url":null,"abstract":"The presence of gas bubbles plays an important role in the generation, scattering and absorption of sound in a liquid. The applications of gas bubbles are diverse, including acoustical oceanography and medical and industrial ultrasound. Although a great deal is known about bubble oscillations in unbounded liquids, it is not very clear to what extent these results are applicable to the dynamics of constrained bubbles. The present study is aimed at investigation of bubble dynamic in the presence of bounding surfaces. The proposed approach uses a bi-spherical coordinate system and is limited to a description of a sufficiently long-wave acoustical field. The choice of a specific coordinate system allows one to take into account the internal symmetry inherent in this problem. A closed form solution was derived for the scattered acoustic field that determines its parametric dependence on bubbles sizes and the separation distance to the interface.","PeriodicalId":330911,"journal":{"name":"2019 International Congress on Ultrasonics","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127422022","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}

{"title":"Analysis of Lamb wave mode repulsion and its implications to the characterisation of adhesive bonding strength","authors":"Y. Lugovtsova, S. Johannesmann, B. Henning, J. Prager","doi":"10.1121/2.0001074","DOIUrl":"https://doi.org/10.1121/2.0001074","url":null,"abstract":"Lamb waves are widely used for non-destructive evaluation of material parameters as well as for detection of defects. Another application of Lamb waves is quality control of adhesive joints. Researchers are currently investigating shear horizontal and zero-group velocity modes for characterisation of the adhesive bonding strength. In a new approach, Lamb wave mode repulsion is used to obtain the coupling strength between different layers to characterise the adhesive bonding strength. The modes of the individual layers become coupled in the multi-layered systems forming particular regions, the so-called mode repulsion regions. This study investigates these modes and their interaction in two-layered plate-like structures with varying coupling strength both numerically, with the Scaled Boundary FEM, and experimentally.","PeriodicalId":330911,"journal":{"name":"2019 International Congress on Ultrasonics","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131023121","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}