Results 71 to 80 of about 14,025 (281)

Covariance and Time Regained in Canonical General Relativity

, 2008
Canonical vacuum gravity is expressed in generally-covariant form in order that spacetime diffeomorphisms be represented within its equal-time phase space. In accordance with the principle of general covariance, the time mapping ${\T}: {\yman} \to {\rman}
A. Einstein, A. E. Fischer, D. Hilbert, E. Cartan, E. Kretschmann, Hájíček, I. Kouletsis, J. Hartle, J. Hartle, J. Stachel, J. L. Anderson, K. V. Kuchař, M. Gell-Mann, M. Gell-Mann, M. Gell-Mann, M. Henneaux, P. A. M. Dirac, P. G. Bergmann, R. Arnowitt, R. W. Lawson, T. P. Shestakova, V. Fock   +21 more
core   +3 more sources

A light‐triggered Time‐Resolved X‐ray Solution Scattering (TR‐XSS) workflow with application to protein conformational dynamics

FEBS Open Bio, EarlyView.
Time‐resolved X‐ray solution scattering captures how proteins change shape in real time under near‐native conditions. This article presents a practical workflow for light‐triggered TR‐XSS experiments, from data collection to structural refinement. Using a calcium‐transporting membrane protein as an example, the approach can be broadly applied to study ...
Fatemeh Sabzian‐Molaei, Fredrik Orädd, Konstantinos Magkakis, Magnus Andersson   +3 more
wiley   +1 more source

Common Coupled Fixed Point Theorem for Geraghty-Type Contraction in Partially Ordered Metric Spaces

Journal of Function Spaces, 2018
We study the existence and uniqueness of common coupled fixed point of four self-mappings for Geraghty-type contraction using weakly compatible mappings in partially ordered metric spaces with common limit range property (denoted by (CLRST)), the ...
Xiao-lan Liu, Mi Zhou, Boško Damjanović   +2 more
doaj   +1 more source

Weak lower semicontinuity of integral functionals and applications

, 2017
Minimization is a reoccurring theme in many mathematical disciplines ranging from pure to applied ones. Of particular importance is the minimization of integral functionals that is studied within the calculus of variations.
Benešová, Barbora, Kružík, Martin
core   +1 more source

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

International 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

Common Fixed Point Theorems for Six Mappings in Generalized Metric Spaces

Abstract and Applied Analysis, 2012
By using the weakly commutative and weakly compatible conditions of self-mapping pairs, we prove some new common fixed point theorems for six self-mappings in the framework of generalized metric spaces. An example is provided to support our result.
Feng Gu
doaj   +1 more source

FIXED POINT THEOREMS FOR WEAKLY COMMUTING AND COMPATIBLE MULTI-VALUED MAPPINGS

Demonstratio Mathematica, 2004
Let \((X, d)\) be a generalized metric space in the sense of \textit{C. F. K. Jung} [Bull. Am. Math. Soc. 75, 113--116 (1969; Zbl 0194.23801)] and \((Cl(X), H)\) the hyperspace induced by \(d\), wherein \(Cl(X)\) stands for the collection of all nonempty closed subsets of \(X\).
Miczko, Antoni, Palczewski, Boleslaw
openaire   +2 more sources

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

Advanced 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, Peipei Chen, Shafia Mukhtar Ibrahim, Mukhtar Lawan Adam, Attia Falak, Mokhotjwa Simon Dhlamini, Hanfu Wang, Lingxiang Jiang, Weiguo Chu   +8 more
wiley   +1 more source

Results on common fixed points in S_b-metric spaces [PDF]

E-Journal of Analysis and Applied Mathematics
In this paper, we establish new common fixed point theorems for pairs of weakly compatible mappings within the framework of S_b-metric spaces. By introducing generalized contractive conditions, we demonstrate the existence and uniqueness of common fixed ...
Pramodkumar Sohanlal Sharma, Chintaman Tukaram Aage   +1 more
doaj   +1 more source

Recent Progress in Oxide‐Based Na‐Ion Conductors

Advanced Engineering Materials, EarlyView.
Recent advances in oxide‐based sodium‐ion conductors are reviewed, focusing on β/β″‐alumina, NASICON‐type compounds, and Na5YSi4O12‐type (N5) silicates, together with emerging perovskite and layered oxides. Improvements in ionic conductivity, compositional tuning, and processing are highlighted.
Bowei Xun, Jian Wang, Hubertus Rainaldo Arindra, Katsuro Hayashi   +3 more
wiley   +1 more source