Results 91 to 100 of about 264 (216)
European Physical Journal C: Particles and Fields, 2018 An anti-de Sitter background four-dimensional type N solution of the Einstein’s field equations, is presented. The matter-energy content pure radiation field satisfies the null energy condition (NEC), and the metric is free-from curvature divergence.
Faizuddin Ahmed
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Land Degradation &Development, EarlyView.ABSTRACT Lateral carbon transport induced by soil erosion is a key component of the global carbon cycle. Over the past 50 years, ecological restoration projects in the Loess Plateau of China have increased vegetation coverage. However, the effects of land use, precipitation variability, and landscape factors on lateral carbon transport remain unclear ...
Ganggang Ke +6 more
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On the dynamics of second-order Lagrangian systems
Electronic Journal of Differential Equations, 2017 In this article we are concerned with improving the twist condition for second-order Lagrangian systems. We characterize a local Twist property and demonstrate how results on the existence of simple closed characteristics can be extended in the case ...
Ronald Adams +2 more
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Refining techniques for high‐frequency monitoring of chlorophyll a fluorescence in estuarine systems
Limnology and Oceanography: Methods, EarlyView.Abstract Concentrations of the photosynthetic pigment chlorophyll a are commonly used as a proxy for phytoplankton biomass in aquatic systems. Traditional methods for extracting chlorophyll a in discrete samples limit measurement frequency, while in situ sensor technology provides high frequency chlorophyll a fluorescence measurements at a more ...
Nicole Dix +10 more
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Proximinality in geodesic spaces
Abstract and Applied Analysis, 2006 Let X be a complete CAT(0) space with the geodesic extension property and Alexandrov curvature bounded below. It is shown that if C is a closed subset of X, then the set of points of X which have a unique nearest point in C is Gδ and of the second Baire ...
A. Kaewcharoen, W. A. Kirk
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Visibility and Intersection Density for Boolean Models in Hyperbolic Space
Mathematische Nachrichten, EarlyView.ABSTRACT For Poisson particle processes in hyperbolic space we introduce and study concepts analogous to the intersection density and the mean visible volume, which were originally considered in the analysis of Boolean models in Euclidean space. In particular, we determine a necessary and sufficient condition for the finiteness of the mean visible ...
Tillmann Bühler +2 more
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Flipping geometric triangulations on hyperbolic surfaces
Journal of Computational GeometryWe consider geometric triangulations of surfaces, i.e., triangulations whose edges can be realized by disjoint geodesic segments. We prove that the flip graph of geometric triangulations with fixed vertices of a flat torus or a closed hyperbolic surface
Vincent Despre +2 more
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Mathematical Methods in the Applied Sciences, Volume 48, Issue 6, Page 6912-6917, April 2025.ABSTRACT Nowadays, a substantial portion of investigations concerning the symmetry analysis of differential equations predominantly adhere to a framework comprising the following key procedures: (i) the derivation of symmetries, (ii) the determination of an optimal system, (iii) the utilization of these symmetries to construct invariants or ...
A. Paliathanasis +2 more
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Active contour model by combining edge and region information discrete dynamic systems
Advances in Mechanical Engineering, 2017 The basic idea of active contour model upon the image segmentation problem is evolved into a closed curve about the functional minimization problems. Active contour model based on edge information takes advantage of gradient information, and it has some ...
Zhifeng Wang, Yan-Jun Liu
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On Geometric Phase Model in the Theory of Curves With Myller Configuration
Mathematical Methods in the Applied Sciences, EarlyView.ABSTRACT In this paper, we introduce a linearly polarized light wave in an optical fiber and rotation of the polarization plane through the Frenet‐type frame with Myller configuration. Since the geometric evaluation and interpretations of a polarized light wave are associated with geometric phase, a new type of geometric phase model has been ...
Zehra İşbilir +2 more
wiley +1 more source