Results 131 to 140 of about 26,941 (300)

Report of the panel on international programs [PDF]

The panel recommends that NASA participate and take an active role in the continuous monitoring of existing regional networks, the realization of high resolution geopotential and topographic missions, the establishment of interconnection of the reference
Anderson, Allen Joel, Fuchs, Karl W., Ganeka, Yasuhiro, Gaur, Vinod, Green, Andrew A., Lambert, Anthony, Rais, Jacub, Reighber, Christopher, Seeger, Herman, Siegfried, W.   +9 more
core   +1 more source

Stress Field and Megathrust Strength in the Western Hellenic Subduction System: Insights From the 2024 Mw 5.9 Strofades Earthquake Sequence, Greece

Geophysical Research Letters, Volume 53, Issue 9, 16 May 2026.
Abstract A M5.9 earthquake occurred on 29 March 2024, offshore near the Strofades Islands, in the western Hellenic Subduction System. Here we present high‐precision earthquake locations and focal mechanisms that suggest the rupture of a NNE‐SSW striking, left‐lateral strike‐slip fault.
G. M. Bocchini, D. Essing, I. Nikolopoulou, A. Dielforder, M. P. Roth, A. Serpetsidaki, E. Sokos, C. P. Evangelidis, R. M. Harrington   +8 more
wiley   +1 more source

Towards an analytical theory of the third-body problem for highly elliptical orbits

, 2016
When dealing with satellites orbiting a central body on a highly elliptical orbit, it is necessary to consider the effect of gravitational perturbations due to external bodies. Indeed, these perturbations can become very important as soon as the altitude
Deleflie, Florent, Lion, Guillaume, Métris, Gilles   +2 more
core  

Photon‐Sphere Modes in Curved Optical Microcavities: A Black‐Hole Analogue Laser

Advanced Science, Volume 13, Issue 28, 18 May 2026.
An optical analogue of a Schwarzschild black hole is realized using curved microcavities that preserve light‐like geodesics. A new family of laser modes confined around the photon sphere is identified alongside conventional whispering‐gallery modes. Analytical theory, numerical simulations, and experiments reveal curvature‐induced confinement, enabling
Chenni Xu, Aswathy Sundaresan, Nazire‐Begüm Kazkal, Clement Lafargue, Lior Zarfaty, Li‐Gang Wang, Ofek Birnholtz, Dominique Decanini, Melanie Lebental, Patrick Sebbah   +9 more
wiley   +1 more source

VAE+DDPG: An Attention‐Enhanced Variational Autoencoder for Deep Reinforcement Learning‐Based Autonomous Navigation in Low‐Light Environments

Advanced Intelligent Systems, Volume 8, Issue 5, May 2026.
Variational Autoencoder+Deep Deterministic Policy Gradient addresses low‐light failures of infrared depth sensing for indoor robot navigation. Stage 1 pretrains an attention‐enhanced Variational Autoencoder (Convolutional Block Attention Module+Feature Pyramid Network) to map dark depth frames to a well‐lit reconstruction, yielding a 128‐D latent code ...
Uiseok Lee, Chanhong Hwang, Hyunseok Kang, Yechan Park, Hangwoo Jin, Tuan Anh Nguyen, Eunmi Choi, Dugki Min   +7 more
wiley   +1 more source

Geodetic results from ISAGEX data [PDF]

Laser and camera data taken during the International Satellite Geodesy Experiment (ISAGEX) were used in dynamical solutions to obtain center-of-mass coordinates for the Astro-Soviet camera sites at Helwan, Egypt, and Oulan Bator, Mongolia, as well as the
Douglas, B. C., Marsh, J. G., Walls, D. M.   +2 more
core   +1 more source

Autoparallels and the Inverse Problem of the Calculus of Variations

Fortschritte der Physik, Volume 74, Issue 5, May 2026.
ABSTRACT We prove that autoparallel curves associated with a torsion‐free but not necessarily metric‐compatible affine connection can be derived from an action principle. We explicitly construct the action functional and show by standard variational techniques that it produces the desired equations.
Lavinia Heisenberg
wiley   +1 more source

Research program of the Geodynamics Branch [PDF]

This report is the Fourth Annual Summary of the Research Program of the Geodynamics Branch. The branch is located within the Laboratory for Terrestrial Physics of the Space and Earth Sciences Directorate of the Goddard Space Flight Center.
Boccucci, B. S., Cohen, S. C., Kahn, W. D.   +2 more
core   +1 more source

Mapping River Bed Topography in Whitewater Rapids Using Bathymetric LiDAR

River Research and Applications, Volume 42, Issue 4, Page 886-900, May 2026.
ABSTRACT Bathymetric LiDAR captures river topography efficiently for clear and shallow water, but for mountain rivers, whitewater rapids still pose challenges. This study proposes a novel method to enable the extraction of bottom returns specifically in turbulent whitewater sections.
Jan Rhomberg‐Kauert, Theresa Himmelsbach, Florian Pöppl, Lucas Dammert, Martin Pfennigbauer, Gottfried Mandlburger   +5 more
wiley   +1 more source

Inverting vertical gravity anomaly gradients using multidirectional data from a mean sea surface model: the case of the Arabian Sea

Earth, Planets and Space
Advancements in satellite altimetry have significantly enhanced high-resolution mean sea surface (MSS) models, enabling the computation of high-resolution vertical gravity anomaly gradient (VGAG) models.
Ruichen Zhou, Xin Liu, Jinyun Guo, Cheinway Hwang, Yongjun Jia, Xiaotao Chang, Heping Sun   +6 more
doaj   +1 more source