Results 21 to 30 of about 2,180,154 (198)

Observations of traveling ionospheric disturbances driven by gravity waves from sources in the upper and lower atmosphere [PDF]

Annales Geophysicae
The observed traveling ionospheric disturbances (TIDs) are attributed to atmospheric gravity waves generated by auroral sources in the lower thermosphere or gravity waves generated in the troposphere by midlatitude weather systems.
P. Prikryl, D. R. Themens, D. R. Themens, J. Chum, S. Chakraborty, R. G. Gillies, J. M. Weygand   +6 more
doaj   +1 more source

Wavelet Analysis of Embolic Heart Sound Detected by Precordial Doppler Ultrasound During Continuous Venous Air Embolism in Dogs

Anesthesia & Analgesia, 1998
The spectrum of the embolic heart sounds (EHS) detected by precordial Doppler ultrasound has been previously characterized, but only on small volumes of venous air embolism (VAE). We sought to determine whether real-time wavelet analysis is useful in analyzing the signals of EHS and whether the embolic power of the EHS for larger volumes of air is ...
Lui, PW, Chan, BCB, Chan, FHY, Poon, PWF, Wang, H, Lam, FK   +5 more
openaire   +5 more sources

Ground-based measurements of ionospheric dynamics

Journal of Space Weather and Space Climate, 2018
Different methods are used to research and monitor the ionospheric dynamics using ground measurements: Digisonde Drift Measurements (DDM) and Continuous Doppler Sounding (CDS).
Kouba Daniel, Chum Jaroslav
doaj   +1 more source

Developments in target micro-Doppler signatures analysis : radar imaging, ultrasound and through-the-wall radar [PDF]

, 2013
Target motions, other than the main bulk translation of the target, induce Doppler modulations around the main Doppler shift that form what is commonly called a target micro-Doppler signature.
Woodbridge, K., Clemente, C., Soraghan, J.J., Balleri, A.   +3 more
core   +5 more sources

The March and April 2023 ionospheric storms over Europe

Frontiers in Astronomy and Space Sciences
This paper presents a deep and comprehensive multi-instrumental analysis of two distinct ionospheric storms occurring in March and April 2023. We investigate the ionospheric response in the middle-latitudinal European region utilizing ionospheric ...
Zbyšek Mošna, Veronika Barta, Kitti Alexandra Berényi, Jens Mielich, Tobias Verhulst, Daniel Kouba, Jaroslav Urbář, Jaroslav Chum, Petra Koucká Knížová, Habtamu Marew, Kateřina Podolská, Rumiana Bojilova   +11 more
doaj   +1 more source

Plasmon‐Enhanced Second‐Harmonic Generation in Atomically Thin Crystalline Silver Nanostructures

Advanced Materials, EarlyView.
Atomically thin crystalline silver films combine vertical quantum confinement with lateral plasmonic field enhancement to boost second‐harmonic generation. Nanoribbon and nanotriangle arrays enable geometry‐tunable infrared plasmon resonances, producing strong SHG from deeply subwavelength metallic volumes compatible with silicon‐based nanophotonics ...
Saad Abdullah, Philipp K. Jenke, Andrew P. Weber, Álvaro Rodríguez Echarri, Vahagn Mkhitaryan, Fadil Iyikanat, Frederik Schiller, Philip Walther, J. Enrique Ortega, Lee A. Rozema, F. Javier García de Abajo   +10 more
wiley   +1 more source

Cross‐Scale Hierarchical Targeted Delivery System Based on Small‐Scale Magnetic Robots

Advanced Robotics Research, EarlyView.
This article reviews a cross‐scale hierarchical targeted delivery system that integrates magnetic continuum robots and magnetic microrobots. By combining rapid long‐range navigation with precise microscale targeting, the system overcomes key limitations of single‐scale approaches.
Junjian Zhou, Zhiqiang Chen, Yuanbiao Ma, Zhiqiang Tang, Qianqian Wang   +4 more
wiley   +1 more source

Intelligent Maintenance Review for Robots: Multimodal Information, Deep Diagnosis and Embodied Artificial Intelligence

Advanced Robotics Research, EarlyView.
This review maps the methods to monitor robots’ health by fusing vibration, sound, control signals, vision, force, and oil information with artificial intelligence. It identifies deep learning, transfer learning, digital twins, and physics‐informed models as key methodological pathways enabling earlier diagnosis, safer human–robot collaboration, and ...
Yuting Qiao, Hongbo Wang, Naipeng Li, Shuo Wang, Yaguo Lei, Tonghai Wu, Junyi Cao   +6 more
wiley   +1 more source

Passive Metasurface Tweezers for Multi‐Scale Orbital Transport and Trapping on Elastic Plates

Advanced Science, EarlyView.
Passive labyrinthine phase encoding converts single‐channel excitation into localized flexural‐wave vortices with programmable orbital angular momentum. The resulting vortex fields enable cross‐scale particle manipulation, including orbital transport, central confinement, and rotational actuation.
Zeyang Bi, Zhiqiang Li, Yunkang Ren, Yugui Peng, Xuefeng Zhu, Liuxian Zhao, Jun Yang, Chuanxing Bi   +7 more
wiley   +1 more source

Remote temperature profiling in the troposphere and stratosphere by the radio-acoustic sounding technique [PDF]

, 1986
Radar application of the radio-acoustic sounding technique uses the Doppler frequency shift of radar echoes returning from the atmospheric wave structure, in association with a traveling acoustic pulse transmitted from the ground, to determine the speed ...
Matuura, N., Inuki, H., Masuda, Y.
core