Results 91 to 100 of about 219,185 (273)

Spontaneous Breaking of Space—Time Symmetries [PDF]

open access: yes, 2007
37 pages, 18 figures. Based on the contribution to "String Theory and Fundamental Interactions. Celebrating Gabriele Veneziano on his 65th Birthday", edited by M. Gasperini and J. Maharana, to be published by Springer, and Lecture given at Les Houches summer school: "String Theory and The Real World From Particle Physics to Astrophysics", Session ...
openaire   +2 more sources

Hopfield Neural Networks for Online Constrained Parameter Estimation With Time‐Varying Dynamics and Disturbances

open access: yesInternational Journal of Adaptive Control and Signal Processing, EarlyView.
This paper proposes two projector‐based Hopfield neural network (HNN) estimators for online, constrained parameter estimation under time‐varying data, additive disturbances, and slowly drifting physical parameters. The first is a constraint‐aware HNN that enforces linear equalities and inequalities (via slack neurons) and continuously tracks the ...
Miguel Pedro Silva
wiley   +1 more source

Non-expanding horizons: multipoles and the symmetry group

open access: yesJournal of High Energy Physics, 2022
It is well-known that blackhole and cosmological horizons in equilibrium situations are well-modeled by non expanding horizons (NEHs) [1–3]. In the first part of the paper we introduce multipole moments to characterize their geometry, removing the ...
Abhay Ashtekar   +3 more
doaj   +1 more source

Evaluation of the Potential of Laser Shock Peening Compared with Cold Expansion for Improving Fatigue Resistance of Riveted Lap Joints of Aerospace Grade 7175 Al Alloy

open access: yesAdvanced Engineering Materials, EarlyView.
This study investigates laser shock peening for enhancing fatigue performance of riveted aerospace aluminum joints. A comparative approach with cold expansion combines fatigue testing and synchrotron X‐ray methods. Integrating mechanical testing with residual stress and strain characterization provides insights into how different treatments affect the ...
Ogün Baris Tapar   +6 more
wiley   +1 more source

Logarithmic angle-dependent gauge transformations at null infinity

open access: yesJournal of High Energy Physics
Logarithmic angle-dependent gauge transformations are symmetries of electromagnetism that are canonically conjugate to the standard O 1 $$ \mathcal{O}(1) $$ angle-dependent u(1) transformations. They were exhibited a few years ago at spatial infinity. In
Oscar Fuentealba, Marc Henneaux
doaj   +1 more source

Ward identities in $\mathcal{N}=1$ supersymmetric SU(3) Yang-Mills theory on the lattice

open access: yes, 2017
The introduction of a space-time lattice as a regulator of field theories breaks symmetries associated with continuous space-time, i.e.\ Poincar{\'e} invariance and supersymmetry.
Ali, Sajid   +7 more
core   +1 more source

Adaptable Tile‐Based Pneumatic Origami through Structurally Coupled Localized Actuation

open access: yesAdvanced Engineering Materials, EarlyView.
This article presents tile‐based pneumatic origami structures with rigid tiles and flexible fabric creases, achieving adaptable properties including morphing shape, selective multistability, and tunable stiffness. Independently pressurized folding bladders at each crease enable structurally coupled localized actuation of origami structures.
Tiantian Li, Jonathan Luntz, Diann Brei
wiley   +1 more source

Non-minimal couplings to U(1)-gauge fields and asymptotic symmetries

open access: yesJournal of High Energy Physics
We analyse the asymptotic symmetries of electromagnetism non-minimally coupled to scalar fields, with non-minimal couplings of the Fermi type that occur in extended supergravity models.
Oscar Fuentealba   +2 more
doaj   +1 more source

Trace Nickel Activated Biphasic Core‐CuOii/Shell‐CuOi Secondary Microspheres Enable Room Temperature Parts‐Per‐Trillion‐Level NO2 Detection

open access: yesAdvanced Engineering Materials, EarlyView.
An idea of designing novel sensors is proposed by creating appropriate Schottky barriers and vacancies between isomorphous Core‐CuOii/ Shell‐CuOi secondary microspheres and enhancing catalytic and spill‐over effects, and electronegativity via spontaneous biphasic separation, self‐assembly, and trace‐Ni‐doping.
Bala Ismail Adamu   +8 more
wiley   +1 more source

A Workflow to Accelerate Microstructure‐Sensitive Fatigue Life Predictions

open access: yesAdvanced Engineering Materials, EarlyView.
This study introduces a workflow to accelerate predictions of microstructure‐sensitive fatigue life. Results from frameworks with varying levels of simplification are benchmarked against published reference results. The analysis reveals a trade‐off between accuracy and model complexity, offering researchers a practical guide for selecting the optimal ...
Luca Loiodice   +2 more
wiley   +1 more source

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