Results 11 to 20 of about 45,803 (270)

Schlieren techniques for observations of long positive sparks: Review and application

High Voltage, 2022
Understanding the mechanism of positive leader discharge is important in lightning protection engineering and the external insulation design in high voltage power transmission systems.
Junjia He, Xiankang Wang, Xiangen Zhao, Juhyeong Lee, Yaping Du, Xiaopeng Liu, Quan Gan, Yang Liu, Yuqin Liao   +8 more
doaj   +2 more sources

Event-Based Background-Oriented Schlieren [PDF]

IEEE Transactions on Pattern Analysis and Machine Intelligence, 2023
Schlieren imaging is an optical technique to observe the flow of transparent media, such as air or water, without any particle seeding. However, conventional frame-based techniques require both high spatial and temporal resolution cameras, which impose bright illumination and expensive computation limitations.
Shintaro Shiba, Friedhelm Hamann, Yoshimitsu Aoki, Guillermo Gallego 0002   +3 more
openaire   +4 more sources

Real-time quantitative Schlieren imaging by fast Fourier demodulation of a checkered backdrop

, 2018
A quantitative synthetic Schlieren imaging (SSI) method based on fast Fourier demodulation is presented. Instead of a random dot pattern (as usually employed in SSI), a 2D periodic pattern (such as a checkerboard) is used as a backdrop to the refractive ...
Wildeman, Sander
core   +2 more sources

Flow over an espresso cup: inferring 3-D velocity and pressure fields from tomographic background oriented Schlieren via physics-informed neural networks [PDF]

Journal of Fluid Mechanics, 2021
Tomographic background oriented Schlieren (Tomo-BOS) imaging measures density or temperature fields in three dimensions using multiple camera BOS projections, and is particularly useful for instantaneous flow visualizations of complex fluid dynamics ...
Shengze Cai, Zhicheng Wang, Frederik Fuest, Y. Jeon, C. Gray, G. Karniadakis   +5 more
semanticscholar   +1 more source

Contactless Acoustic Trapping of Hoverflies for Behavioral Studies. [PDF]

Ann N Y Acad Sci
We present a contactless tethering device based on acoustic levitation. Opposing ultrasonic transducers generate standing waves, creating stable pressure nodes that enable the sustained levitation of hoverflies (Episyrphus balteatus). We show that acoustic levitation does not appear to affect hoverfly behavior.
Gaillard T, Contreras V, Martinez D, Viollet S.   +3 more
europepmc   +2 more sources

Assessment and application of optical flow in background-oriented schlieren for compressible flows

Experiments in Fluids, 2022
Optical flow provides an opportunity to elevate the resolution and sensitivity of deflection sensing in background-oriented schlieren (BOS). Despite extensive relevant literature within the field of computer vision, there is a lack of proper ...
B. O. Cakir, S. Lavagnoli, B. Saracoglu, C. Fureby   +3 more
semanticscholar   +1 more source

A robust physics-based method to filter coherent wavepackets from high-speed schlieren images [PDF]

Journal of Fluid Mechanics, 2021
A complete understanding of jet dynamics is greatly enabled by the accurate separation of acoustically efficient wavepackets from their higher-energy convecting turbulent counterparts.
Chitrarth Prasad, D. Gaitonde
semanticscholar   +1 more source

Methodology of designing compact schlieren systems using off-axis parabolic mirrors.

Applied Optics, 2022
Schlieren imaging is widely adopted in applications where fluid dynamics features are of interest. However, traditional Z-type schlieren systems utilizing on-axis mirrors generally require large system footprints due to the need to use high f-number ...
Lingzhi Zheng, A. J. Susa, Ronald K. Hanson   +2 more
semanticscholar   +1 more source

Petrography and geochemistry of the topaz-bearing granite stocks in Artjärvi and Sääskjärvi, western margin of the Wiborg rapakivi granite batholith [PDF]

Bulletin of the Geological Society of Finland, 2002
The Artjärvi and Sääskjärvi granite stocks at the western margin of the Wiborg rapakivi batholith are multiphase rapakivi granite intrusions in which the most evolved phase is topaz-bearing granite.
S. Lukkari
doaj   +1 more source

Evaluation of the Effects of Harmine on β-cell Function and Proliferation in Standardized Human Islets Using 3D High-Content Confocal Imaging and Automated Analysis

Frontiers in Endocrinology, 2022
Restoration of β-cell mass through the induction of proliferation represents an attractive therapeutic approach for the treatment of diabetes. However, intact and dispersed primary islets suffer from rapidly deteriorating viability and function ex vivo ...
Alexandra C. Title, Maria Karsai, Joan Mir-Coll, Özlem Yavas Grining, Chantal Rufer, Sebastian Sonntag, Felix Forschler, Sayro Jawurek, Thomas Klein, Burcak Yesildag   +9 more
doaj   +1 more source