The acoustic nonlinearity parameter is determined from the amplitudes of the fundamental and second harmonic component of the acoustic wave propagating through the material. However, the generally used through-transmission based measurements with PZT transducers contain high system nonlinearity, so that the received second harmonic component includes an extra component caused by the transducer, which significantly decrease the reliability of measurements. In this study, we proposed a novel method to reduce the system nonlinearity in the conventional through-transmission based measurements by adding a simple process in which the transmitting and receiving transducers are in direct contact without a specimen. The proposed method was experimentally validated for two materials, Al6061-T6 and Fused Silica. For both materials, several specimens with different thickness were prepared, and the measurement results showed that the magnitude of the second harmonic was proportional to the thickness, but there was an offset due to system nonlinearity. On the other hand, after applying the proposed technique, the offsets were greatly reduced, and furthermore, this performance was maintained even when the transducer setup was changed, and the ratio of nonlinearity parameters measured for the two materials was in good agreement with the known literature value.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.ultras.2024.107484 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Co-assemblies of Silver Nanoclusters and Fullerenols With Enhanced Third-Order Nonlinear Optical Response.
Small Methods
January 2025
National Engineering Research Center for Colloidal Materials, Key Laboratory of Colloid and Interface Chemistry (Ministry of Education), School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China.
Exploring potential third-order nonlinear optical (NLO) materials attracts ever-increasing attention. Given that the atomically precise and rich adjustable structural features of silver nanoclusters (Ag NCs), as well as the unique π-electron conjugated system of carbon-based nanomaterials, a supramolecular co-assembly amplification strategy to enhance the luminescent intensity and NLO performance of the hybrids of the two components, are constructed and the relationship between structures and optical properties are investigated. By combining water soluble Ag NCs [(NH)[Ag(mna)] (Hmna = 2-mercaptonicotinic acid, abbreviated to Ag─NCs hereafter) containing uncoordinated carboxyl groups with water-soluble fullerene derivatives modified with multiple hydroxyl groups (fullerenols, C─OH), the π-electron delocalization is expanded owing to non-covalent hydrogen bonding effect between Ag6─NCs and C─OH, which provides a feasible basis for realizing the NLO response.
View Article and Find Full Text PDFAn Adaptive Spatio-Temporal Traffic Flow Prediction Using Self-Attention and Multi-Graph Networks.
Sensors (Basel)
January 2025
Department of Computer Science, King AbdulAziz University, Jeddah 21589, Saudi Arabia.
Traffic flow prediction is a pivotal element in Intelligent Transportation Systems (ITSs) that provides significant opportunities for real-world applications. Capturing complex and dynamic spatio-temporal patterns within traffic data remains a significant challenge for traffic flow prediction. Different approaches to effectively modeling complex spatio-temporal correlations within traffic data have been proposed.
View Article and Find Full Text PDFAn FPGA-Based SiNW-FET Biosensing System for Real-Time Viral Detection: Hardware Amplification and 1D CNN for Adaptive Noise Reduction.
Sensors (Basel)
January 2025
Department of Computer Science, Faculty of Sciences and Humanities Sciences, Majmaah University, Al Majmaah 11952, Saudi Arabia.
Impedance-based biosensing has emerged as a critical technology for high-sensitivity biomolecular detection, yet traditional approaches often rely on bulky, costly impedance analyzers, limiting their portability and usability in point-of-care applications. Addressing these limitations, this paper proposes an advanced biosensing system integrating a Silicon Nanowire Field-Effect Transistor (SiNW-FET) biosensor with a high-gain amplification circuit and a 1D Convolutional Neural Network (CNN) implemented on FPGA hardware. This attempt combines SiNW-FET biosensing technology with FPGA-implemented deep learning noise reduction, creating a compact system capable of real-time viral detection with minimal computational latency.
View Article and Find Full Text PDFVariable-Parameter Impedance Control of Manipulator Based on RBFNN and Gradient Descent.
Sensors (Basel)
December 2024
Xi'an Institute of Optics and Precision Mechanics of CAS, Xi'an 710119, China.
During the interaction process of a manipulator executing a grasping task, to ensure no damage to the object, accurate force and position control of the manipulator's end-effector must be concurrently implemented. To address the computationally intensive nature of current hybrid force/position control methods, a variable-parameter impedance control method for manipulators, utilizing a gradient descent method and Radial Basis Function Neural Network (RBFNN), is proposed. This method employs a position-based impedance control structure that integrates iterative learning control principles with a gradient descent method to dynamically adjust impedance parameters.
View Article and Find Full Text PDFSynthesis, optical linear and non-linear characterization and metal ion sensing application of some novel thieno[2,3-b]thiophene-2,5-dicarbohydrazide Schiff base derivatives.
Sci Rep
January 2025
Department of Physics, Faculty of Science, Sohag University, Sohag, 82524, Egypt.
Synthesized 3,4-Diaminothieno[2,3-b]thiophene-2,5-dicarbohydrazide (DTT) Schiff base derivatives newly were synthesized by attaching with different aldehydes, deposited in thin film form by thermal evaporation technique, and characterized by UV-Visible-NIR spectroscopy, FT-IR, NMR, and elemental analysis. It is revealed that compound 4 has the highest absorption peak intensity at 586 nm. The allied absorption, dielectric, and dispersion parameters have been calculated and discussed.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!