Ultrasonic guided wave (UGW)-based condition monitoring has shown great promise in detecting, localizing, and characterizing damage in complex systems. However, the application of guided waves for damage detection is challenging due to the existence of multiple modes and dispersion. This results in distorted wave packets with limited resolution and the interference of multiple reflected modes. To develop reliable inspection systems, either the transducers have to be optimized to generate a desired single mode of guided waves with known dispersive properties, or the frequency responses of all modes present in the structure must be known to predict wave interaction. Currently, there is a lack of methods to predict the response spectrum of guided wave modes, especially in cases when multiple modes are being excited simultaneously. Such methods are of vital importance for further understanding wave propagation within the structures as well as wave-damage interaction. In this study, a novel method to predict the response spectrum of guided wave modes was proposed based on Fourier analysis of the particle velocity distribution on the excitation area. The method proposed in this study estimates an excitability function based on the spatial dimensions of the transducer, type of vibration, and dispersive properties of the medium. As a result, the response amplitude as a function of frequency for each guided wave mode present in the structure can be separately obtained. The method was validated with numerical simulations on the aluminum and glass fiber composite samples. The key findings showed that it can be applied to estimate the response spectrum of a guided wave mode on any type of material (either isotropic structures, or multi layered anisotropic composites) and under any type of excitation if the phase velocity dispersion curve and the particle velocity distribution of the wave source was known initially. Thus, the proposed method may be a beneficial tool to explain and predict the response spectrum of guided waves throughout the development of any structural health monitoring system.
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http://dx.doi.org/10.3390/s17081825 | DOI Listing |
J Med Genet
January 2025
Department of Public Health and Pediatric Sciences, University of Turin, Torino, Italy
Lateralised overgrowth (LO) is characterised by the asymmetric increase in the size of any part of the body exceeding 10% compared with the unaffected contralateral one. LO is a key feature in various syndromic overgrowth disorders, such as Beckwith-Wiedemann spectrum and -related overgrowth spectrum (PROS). However, it can also present as isolated (ILO).
View Article and Find Full Text PDFJ Autism Dev Disord
January 2025
Department of Psychology, University of Alabama at Birmingham, AL, Birmingham, USA.
Purpose: Prior research demonstrates that children with autism are more likely to experience unintentional injuries than the general population. Limited research exists on the symptoms or traits directly related to autism and this elevated injury rate, especially from the perspective of families with children with autism. This study used qualitative methodology to elucidate risk factors that may contribute to unintentional injuries in children with autism from the perspective of mothers raising children with autism.
View Article and Find Full Text PDFSemin Ophthalmol
January 2025
Department of Ophthalmology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, PA, USA.
Objective: Ciliary body medulloepithelioma (CBME), a pediatric intraocular tumor with potential for locally aggressive behavior and metastasis, may present with a diverse spectrum of clinical and histopathologic features leading to diagnostic and management challenges. Examination of unusual CBME cases highlights challenges and modern diagnostic techniques which facilitate accurate diagnosis and guide management.
Methods: A retrospective clinicopathologic analysis of 6 patients with unusual clinical or pathologic features of CBME was performed.
Elucidating the genetic contributions to Parkinson's disease (PD) etiology across diverse ancestries is a critical priority for the development of targeted therapies in a global context. We conducted the largest sequencing characterization of potentially disease-causing, protein-altering and splicing mutations in 710 cases and 11,827 controls from genetically predicted African or African admixed ancestries. We explored copy number variants (CNVs) and runs of homozygosity (ROHs) in prioritized early onset and familial cases.
View Article and Find Full Text PDFRev Cardiovasc Med
January 2025
Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, 510080 Guangzhou, Guangdong, China.
Inherited cardiac arrhythmias, which may lead to sudden cardiac death, represent a significant health risk, with genetic factors playing a key role in their development. The ankyrin 2 () gene, encoding ankyrin-B, is implicated in several heritable arrhythmia syndromes. variants have been linked to an inherited condition known as "ankyrin-B syndrome", which manifests as a spectrum of cardiac arrhythmias and cardiomyopathy.
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