Magnetic field aligned filaments such as blobs and edge localized mode filaments carry significant amounts of heat and particles to the plasma facing components and they decrease their lifetime. The dynamics of these filaments determine at least a part of the heat and particle loads. These dynamics can be characterized by their translation and rotation. In this paper, we present an analysis method novel for fusion plasmas, which can estimate the angular velocity of the filaments on frame-by-frame time resolution. After pre-processing, the frames are two-dimensional (2D) Fourier-transformed, then the resulting 2D Fourier magnitude spectra are transformed to log-polar coordinates, and finally the 2D cross-correlation coefficient function (CCCF) is calculated between the consecutive frames. The displacement of the CCCF's peak along the angular coordinate estimates the angle of rotation of the most intense structure in the frame. The proposed angular velocity estimation method is tested and validated for its accuracy and robustness by applying it to rotating Gaussian-structures. The method is also applied to gas-puff imaging measurements of filaments in National Spherical Torus Experiment plasmas.
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http://dx.doi.org/10.1063/5.0128818 | DOI Listing |
Bioengineering (Basel)
January 2025
Department of Intelligent Robotics, Sungkyunkwan University, Suwon 16419, Republic of Korea.
Rehabilitation of gait function in post-stroke hemiplegic patients is critical for improving mobility and quality of life, requiring a comprehensive understanding of individual gait patterns. Previous studies on gait analysis using unsupervised clustering often involve manual feature extraction, which introduces limitations such as low accuracy, low consistency, and potential bias due to human intervention. This cross-sectional study aimed to identify and cluster gait patterns using an end-to-end deep learning approach that autonomously extracts features from joint angle trajectories for a gait cycle, minimizing human intervention.
View Article and Find Full Text PDFBioinspir Biomim
January 2025
Shaanxi Aerospace Propulsion Research Institute Co., Ltd., No. 996, Tiangu 7th Road, Xi'an, 710072, CHINA.
Bird-like flapping-wing aerial vehicles (BFAVs) represent a significant advancement in the application of bird biology to aircraft design, with scaling analysis serving as an effective tool for identifying this design process. From the perspective of aviation designers, this paper systematically organizes the scaling laws of birds that are closely related to the design of BFAVs. An intriguing topic further explored is the comparison between birds and BFAVs from the standpoint of scaling, along with an examination of the differences in relevant design parameters.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
School of Environmental Science and Engineering, Nanjing Tech University, Jiangsu 211816, China; Sino-Portuguese Joint International Laboratory of Aquatic Toxicology, Nanjing Tech University, 30 South Puzhu Road, Nanjing, Jiangsu Province 211816, China. Electronic address:
Gabapentin (GBP), a pharmaceutical widely used for seizures and neuropathic pain, has emerged as a contaminant in global aquatic environments, raising concerns about its ecological impact. This study investigated the effects of environmentally relevant concentrations of GBP (0, 1, 10, 1000 μg/L) on visual development in zebrafish (Danio rerio). Behavioral assays showed that GBP exposure enhanced light sensitivity, as indicated by a significant increase in total travel distance (TTD) in all exposure groups compared to controls.
View Article and Find Full Text PDFFront Sports Act Living
January 2025
Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands.
Background: It is assumed that the tennis serve is performed according to the kinetic chain principle in which a proximal-to-distal sequence in peak angular velocities of subsequent body segments can be observed to reach high end point ball velocities. The aim of the present study was to investigate if the magnitude and (intersegmental) timing of peak angular velocities of body segments in professional tennis players are different between first and second serves and if they are associated with serve performance.
Methods: Eight (two female and six male) professional tennis players performed each 48 tennis serves on a tennis court.
J Sports Sci
January 2025
Institute of Biomechanics and Orthopaedics, German Sport University, Cologne, Germany.
In snowboard freestyle, rotation is the key indicator of trick difficulty, encouraging riders to perform tricks with more rotation. In many cases, snowboarders learn and practice tricks using training tools such as trampolins and/or landingbags before they transfer this tricks on-snow. It has not yet been scientifically investigated which movement parameters are primarily responsible for the acquisistion of increasingly difficult cork tricks.
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