Effects of maximum aggregate size on UPV of brick aggregate concrete.

abstract：:Since the identification of micro-cracks in engineering materials is very valuable in understanding the initial and slight changes in mechanical properties of materials under complex working environments, numerical simulations on the propagation of the low frequency S0 Lamb wave in thin plates with randomly distribute...

journal_title：Ultrasonics

authors： Zhao Y,Li F,Cao P,Liu Y,Zhang J,Fu S,Zhang J,Hu N

更新日期：2017-08-01 00:00:00

abstract：:In this paper, the development of modified beamforming methods, Filtered Delay Weight Multiply and Sum (F-DwMAS) and Filtered Delay Euclidian-Weighted Multiply and Sum (F-DewMAS), are reported. These methods were investigated on a minimum-redundancy synthetic aperture technique, called as 2 element Receive Synthetic A...

journal_title：Ultrasonics

authors： Vayyeti A,Thittai AK

更新日期：2021-02-01 00:00:00

abstract：:The accurate estimation of time of flight (TOF) of an ultrasonic signal is essential in ultrasonic non-destructive testing (NDT). A novel method for TOF estimation based on the short-time Fourier transform (STFT) is proposed in this paper. Firstly, the time and frequency components of ultrasonic echoes are represented...

journal_title：Ultrasonics

authors： Lu Z,Ma F,Yang C,Chang M

更新日期：2020-04-01 00:00:00

abstract：:Our study aims at the creation of a numerical toolbox that describes wave propagation in samples containing internal contacts (e.g. cracks, delaminations, debondings, imperfect intergranular joints) of known geometry with postulated contact interaction laws including friction. The code consists of two entities: the co...

journal_title：Ultrasonics

authors： Delrue S,Aleshin V,Truyaert K,Bou Matar O,Van Den Abeele K

更新日期：2018-01-01 00:00:00

abstract：:The acoustic source localization technique for anisotropic plates proposed by the authors in an earlier publication ([1] Kundu et al., 2012) is improved in this paper by adopting some modifications. The improvements are experimentally verified on anisotropic flat and curved composite plates. Difficulties associated wi...

journal_title：Ultrasonics

authors： Nakatani H,Kundu T,Takeda N

更新日期：2014-09-01 00:00:00

abstract：:This paper presents a study on the worsening caused by a random perturbation of the weighting window (modeling, in this way, the uncertainty on the channel sensitivity), or by an alteration of the shape of the transmitted pulse, for a wideband array. In the stability evaluation, main-lobe width and signal to noise rat...

journal_title：Ultrasonics

authors： Curletto S,Parodi C,Trucco A

更新日期：2004-04-01 00:00:00

abstract：:We develop a new ultrasonic imaging framework for non-destructive testing of an immersed specimen featuring an irregular top surface and demonstrate its capability of accurately depicting the lower surfaces of multiple damages hidden in the specimen. Central to the framework is a multistep angular spectrum approach (A...

journal_title：Ultrasonics

authors： Yang X,Wang K,Xu Y,Xu L,Hu W,Wang H,Su Z

更新日期：2020-12-01 00:00:00

abstract：:Geometrical and material property changes cause deviations in the resonant conditions used for noncollinear wave mixing. These deviations are predicted and observed using the SV(ω1)+L(ω2)→L(ω1+ω2) interaction, where SV and L are the shear vertical and longitudinal waves, respectively, and ω1, ω2 are their frequencies....

journal_title：Ultrasonics

authors： Demčenko A,Mainini L,Korneev VA

更新日期：2015-03-01 00:00:00

abstract：:A new method of spatial compound imaging is presented that improves image quality without the usual requirement to decrease the frame rate. The new method of imaging utilizes three transducers for data acquisition. The transducer located at the center of the transducer system is a phased array probe that acts as both ...

journal_title：Ultrasonics

authors： Behar V,Adam D,Friedman Z

更新日期：2003-07-01 00:00:00

abstract：:An electrical sensory perception threshold technique has been developed for use with human volunteers. This technique has been used to reproducibly quantify the effects of three different commercially available topical anaesthetic preparations on superficial sensory cells (nociceptors) in the skin. Low intensities (0....

journal_title：Ultrasonics

authors： Williams AR

更新日期：1990-05-01 00:00:00

abstract：:We studied thickness-shear and thickness-twist vibrations of a monolithic, two-pole crystal filter made from a plate of AT-cut quartz. The scalar differential equations derived by Tiersten and Smythe for electroded and unelectroded quartz plates were employed which are valid for both the fundamental and the overtone m...

journal_title：Ultrasonics

authors： Zhao Z,Qian Z,Wang B,Yang J

更新日期：2015-04-01 00:00:00

abstract：:The threshold filter is a frequently used technique in ultrasound B-scan to reject the small echoes contributed from backscattering that blur the tissue interface and reduce the image contrast. Note that using the threshold based on one value would simultaneously destroy local waveform features of the reflection echoe...

journal_title：Ultrasonics

authors： Tsui PH,Chang CC,Chang CC,Huang NE,Ho MC

更新日期：2009-05-01 00:00:00

abstract：:Single clouds of cavitation bubbles, driven by 254kHz focused ultrasound at pressure amplitudes in the range of 0.48-1.22MPa, have been observed via high-speed shadowgraphic imaging at 1×10(6) frames per second. Clouds underwent repetitive growth, oscillation and collapse (GOC) cycles, with shock-waves emitted periodi...

journal_title：Ultrasonics

authors： Johnston K,Tapia-Siles C,Gerold B,Postema M,Cochran S,Cuschieri A,Prentice P

更新日期：2014-12-01 00:00:00

abstract：:In the food industry, ultrasonic cutting is used to improve separation by a reduction of the cutting force. This reduction can be attributed to the modification of tool-workpiece interactions at the cutting edge and along the tool flanks because of the superposition of the cutting movement with ultrasonic vibration of...

journal_title：Ultrasonics

authors： Schneider Y,Zahn S,Schindler C,Rohm H

更新日期：2009-06-01 00:00:00

abstract：:Steel-concrete modular construction is increasingly used in nuclear structure construction. Conventional nondestructive testing methods are not able to detect internal concrete defects because the thick concrete wall is covered by steel plates. An ultrasonic guided method is proposed to detect honeycombs and voids aro...

journal_title：Ultrasonics

authors： Sun H,Zhu J

更新日期：2020-04-01 00:00:00

abstract：:The local evaluation of several parameters of a crack is realized with a nonlinear laser ultrasonic method. The method is based on the sample excitation by two laser beams, independently intensity modulated at two cyclic frequencies ωH and ωL (ωH≫ωL) and on the detection of nonlinear frequency-mixing ultrasonic compon...

journal_title：Ultrasonics

authors： Mezil S,Chigarev N,Tournat V,Gusev V

更新日期：2016-07-01 00:00:00

abstract：:To understand the effect of the sound field on sonochemical luminescence, the exact sound pressure must be determined in each field. In this study it was determined by the Shlieren method, which measures the sound pressure without mixing the sound fields. We compared the efficiency of the sonochemical luminescence in ...

journal_title：Ultrasonics

authors： Yanagida H,Masubuchi Y,Minagawa K,Takimoto J,Ogata T,Koyama K

更新日期：2000-03-01 00:00:00

abstract：:In this paper, te edge mode variation is studied with three different methods: the reciprocal work method, already used by Torvik [J. Acoust. Soc. Am. 41 (1967) 346] to model this phenomenon, the S-parameter method and a finite element model that are applied for the first time to the study of the edge resonance. Moreo...

journal_title：Ultrasonics

authors： Le Clezio E,Predoi MV,Castaings M,Hosten B,Rousseau M

更新日期：2003-01-01 00:00:00

abstract：:A reformulation of the Thomson-Haskell method is presented for calculating the reflection coefficients of multilayer structure immersing in the coupling fluid. Instead of directly multiplying the layer propagator matrix, the new method splits the layer propagator matrix and excursively determines the interface stiffne...

journal_title：Ultrasonics

authors： Chen J,Bai X,Yang K,Ju BF

更新日期：2012-12-01 00:00:00

abstract：:The attenuation of ultrasound in homogenates of bovine skeletal muscle and suspensions of myofibrils was measured over the frequency range 1.5-7 MHz, and found to be proportional to protein concentration in both. In the homogenates it varied with frequency and temperature in a similar way to the attenuation in post ri...

journal_title：Ultrasonics

authors： Shore D,Miles CA

更新日期：1988-07-01 00:00:00

abstract：:Effective receive beamforming in medical ultrasound imaging is important for enhancing spatial and contrast resolution. In current ultrasound receive beamforming, a constant sound speed (e.g., 1540m/s) is assumed. However, the variations of sound speed in soft tissues could introduce phase distortions, leading to degr...

journal_title：Ultrasonics

authors： Yoon C,Lee Y,Chang JH,Song TK,Yoo Y

更新日期：2011-10-01 00:00:00

abstract：:It is well known that harmonic bounded Gaussian beams undergo a transformation into two bounded beams upon reflection on a solid immersed in a liquid. The effect is known as the Schoch effect and can be found at the Rayleigh angle for thick plates and at the different Lamb angles for thin plates. Here, a study is made...

journal_title：Ultrasonics

authors： Declercq NF

更新日期：2006-12-22 00:00:00

abstract：:The method of wave function expansion is adopted to study the three dimensional scattering of a time-harmonic plane progressive sound field obliquely incident upon a multi-layered hollow cylinder with interlaminar bonding imperfection. For the generality of solution, each layer is assumed to be cylindrically orthotrop...

journal_title：Ultrasonics

authors： Rajabi M,Hasheminejad SM

更新日期：2009-12-01 00:00:00

abstract：:In this paper, high-speed photography was used to investigate the intrinsic dynamics of subharmonious surface wave in a vertical vibrated and idealized bidimensional granular layer. Using the high-speed photography, velocity fields of the granular layer at different stages through two cycles were obtained, which show ...

journal_title：Ultrasonics

authors： Zhang P,Huang K,Miao G,Wei R

更新日期：2006-12-22 00:00:00

abstract：:B-Scan images have been used as a means of detecting the onset of cavitation in tissues. New echoes appearing during simultaneous sonication with therapeutic ultrasound have often been attributed to bubble formation. In this study temperature rises up to 15 degrees C W-1 cm2 in guinea pig leg (post-mortem) were found,...

journal_title：Ultrasonics

authors： Watmough DJ,Davies HM,Quan KM,Wytch R,Williams AR

更新日期：1991-07-01 00:00:00

abstract：:The focus of contrast-enhanced ultrasound research has developed beyond visualizing the blood pool and its flow to new areas such as perfusion imaging, drug and gene therapy, and targeted imaging. In this work comparison between the application of polymer- and phospholipid-shelled ultrasound contrast agents (UCAs) for...

journal_title：Ultrasonics

authors： Grishenkov D,Kari L,Brodin LK,Brismar TB,Paradossi G

更新日期：2011-01-01 00:00:00

abstract：:The goal standard of contrast echocardiography is the absolute measure of myocardial perfusion using a contrast agent. Actually, several contrast agents are developed. All these agents show left ventricular opacification after intravenous injection. However, none of these agents shows an acceptable enhancement of the ...

journal_title：Ultrasonics

authors： Bouakaz A,de Jong N,Cachard C,Jouini K

更新日期：1998-02-01 00:00:00

abstract：:The conventional acoustic nonlinear technique to evaluate the contact acoustic nonlinearity (CAN) at solid-solid contact interfaces (e.g., closed cracks), which uses the through-transmission of normally incident bulk waves, is limited in that access to both the inner and outer surfaces of structures for attaching puls...

journal_title：Ultrasonics

authors： Nam T,Lee T,Kim C,Jhang KY,Kim N

更新日期：2012-08-01 00:00:00

abstract：:Theoretical formulation for the problem of second harmonic guided waves in pipes is presented from the principles of continuum mechanics. The formulation is carried out in the reference configuration of the pipe with an emphasis on the correct use of the "Divergence" operator in the reference configuration. Second har...

journal_title：Ultrasonics

authors： Chillara VK,Lissenden CJ

更新日期：2013-04-01 00:00:00

abstract：:In general, the design and analysis of ultrasonic motor and motor's control strategy are based on mathematical model. The academic model is widely used in the analysis of traveling wave ultrasonic motor (TWUSM). But the dispersive characteristic of piezoelectric ceramics and other complicated process, such as the fric...

journal_title：Ultrasonics

authors： Jingzhuo S,Dongmei Y

更新日期：2014-02-01 00:00:00