A novel method for Estimating Time of Flight of ultrasonic echoes through short-time Fourier transforms.

Ultrasonics

College of Information Science and Engineering, Guangxi University for Nationalities, Guangxi Nanning 530006, China.

Published: April 2020

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 by a STFT. Then, the STFT spectrum of the echoes is projected onto the time domain. Finally, the TOF is estimated by calculating the location of the maximum modulus of STFT spectrum of the signal. A nonlinear Least Squares (LS) estimation method based on Modified Gauss-Newton (MGN) is employed to improve the estimation accuracy. The TOFs of multi-component echo signals are estimated by successive windowing. Numerical simulations and experiment tests show the performance of the proposed method.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ultras.2020.106104DOI Listing

Publication Analysis

Top Keywords

novel method
8
time flight
8
ultrasonic echoes
8
short-time fourier
8
stft spectrum
8
method estimating
4
time
4
estimating time
4
ultrasonic
4
flight ultrasonic
4

Similar Publications

Objective: Intraventricular hemorrhage (IVH) is a serious condition with high mortality rates and poor functional outcome in survivors. Treatment includes external ventricular drains (EVDs), which are associated with several complications. This study reports the clinical outcome and complication rate in patients with primary IVH (pIVH) and secondary IVH treated with EVDs.

View Article and Find Full Text PDF

Objective: Mixed-reality (MR) applications provide opportunities for technical rehearsal, education, and estimation of surgical performance without the risk of patient harm. In this study, the authors provide a structured literature review on the current state of MR applications and their effects on neurosurgery training. They also introduce an MR prototype for neurosurgical spine training.

View Article and Find Full Text PDF

Objective: The purpose of this study was to quantitatively measure the split-step skills of the world's top badminton players to clarify the characteristics underlying these skills when moving into the forehand position in the rear court.

Methods: We analyzed the four best ranking players (1st to 4th) in the men's singles competition at the World Badminton Federation (BWF) World Championships 2023, a world tournament whose match videos are available online. Analysis 1 was conducted to determine the location of the players' feet on the court when performing a split-step while moving to the forehand rear court, as well as the width of the stance and the reaction time from that stance to taking the first step.

View Article and Find Full Text PDF

Profile and Usefulness of Serum Cytokines to Predict Prognosis in Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease.

Neurol Neuroimmunol Neuroinflamm

March 2025

Hospices Civils de Lyon, Service de Neurologie, Sclérose en Plaques, Pathologies de la Myéline et Neuro-Inflammation-Hôpital Neurologique Pierre Wertheimer, Bron Cedex.

Objectives: To characterize the serum cytokine profile in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) at onset and during follow-up and assess their utility for predicting relapses and disability.

Methods: This retrospective multicentric cohort study included patients aged 16 years and older meeting MOGAD 2023 criteria, with serum samples collected at baseline (≤3 months from disease onset) and follow-up (≥6 months from the baseline), and age-matched and time to sampling-matched patients with multiple sclerosis (MS). Eleven cytokines were assessed using the ELLA system.

View Article and Find Full Text PDF

A novel photocatalytic method for the synthesis of 1,4-benzoxazepine using 2-alkoxyarylaldehyde as an oxygen source and -arylglycine as a nitrogen source has been reported. This method is mild, efficient, and fast, and the corresponding reaction can be completed within 2 h at room temperature under a nitrogen atmosphere and light-irradiation conditions. Mechanistic studies have confirmed that this scheme involves the decarboxylation cyclization of -arylglycine and provides a convenient pathway for the preparation of various 2-alkyl--phenyl-substituted 1,4-benzoxazepine.

View Article and Find Full Text PDF

Want 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!