Results 41 to 50 of about 3,675 (265)

Guiding and Manipulating Light Fields in Microstructured Liquid Crystals

Advanced Physics Research, EarlyView.
This review summarizes recent advances in guided‐wave optics enabled by microstructured liquid crystal (LC) devices, covering their fundamental material properties, key degree of freedom for dynamic light field manipulations. The advances of linear guided‐wave optics, nonlinear‐optics with spatial optical solitons, and microlasers in LC‐based devices ...
Shan‐shan Chang, Yong‐shuai Li, Jin‐hui Chen   +2 more
wiley   +1 more source

There Are No Conformal Einstein Rescalings of Pseudo-Riemannian Einstein Spaces with n Complete Light-Like Geodesics

Mathematics, 2019
In the present paper, we study conformal mappings between a connected n-dimension pseudo-Riemannian Einstein manifolds. Let g be a pseudo-Riemannian Einstein metric of indefinite signature on a connected n-dimensional manifold M.
Josef Mikeš, Irena Hinterleitner, Nadezda Guseva   +2 more
doaj   +1 more source

Optimizing Strategies for Non‐Invasive Prospection of Settlements in the Intertidal Zone: A Case Study From the Centre of the Drowned Medieval Village of Tolsende (Scheldt Estuary, the Netherlands)

Archaeological Prospection, EarlyView.
ABSTRACT Medieval and early modern drowned villages in the intertidal zone of the Scheldt estuary (the Netherlands) constitute intriguing yet largely understudied components of north‐western Europe's underwater cultural heritage. Despite their high archaeological potential as time capsules of past settlement landscapes, research has remained limited ...
Jan Trachet, Sarah Bäumler, Stefan Krojer, Jeroen Verhegge, Wim De Clercq, Philippe De Smedt, Wouter H. Maes, Bente S. Majchczack, Immo Trinks, Dennis Wilken   +9 more
wiley   +1 more source

The geometry of inflationary observables: Lifts, flows, equivalence classes

Physics Letters B
The Eisenhart lift allows formulating the dynamics of a scalar field in a potential as pure geodesic motion in a curved field-space manifold involving an additional fictitious vector field. Making use of the formalism in the context of inflation, we show
Georgios K. Karananas, Marco Michel, Javier Rubio   +2 more
doaj   +1 more source

Image Segmentation Using GAC Model Combining with GVF and Balloon Force

Journal of Algorithms & Computational Technology, 2015
The geodesic active contour (GAC) model has been widely used due to the high precision of edge detection and the continuity of boundaries. However, compared to the gradient vector flow (GVF) field, it usually has poor performance in the object boundaries
Haiping Xu, Zhenmei Lin, Yanqing Guo, Meiqing Wang   +3 more
doaj   +1 more source

Higher-spin gravity’s “string”: new gauge and proof of holographic duality for the linearized Didenko-Vasiliev solution

Journal of High Energy Physics, 2022
We consider type-A higher-spin gravity in AdS4, holographically dual to a free U(N ) vector model on the boundary. We study the linearized version of the Didenko-Vasiliev “BPS black hole”, which we view as this theory’s equivalent of the fundamental ...
Vyacheslav Lysov, Yasha Neiman
doaj   +1 more source

Multifactorial Screening for Fine‐Scale Selection of CCS Industrial Clusters and Hubs in Brazil

Greenhouse Gases: Science and Technology, EarlyView.
ABSTRACT As Brazil moves toward implementing its decarbonization commitments, carbon capture and storage (CCS) hubs are emerging as a key pathway for large‐scale CO2 abatement in hard‐to‐abate sectors. This paper presents a multifactorial, data‐driven framework to screen and prioritize potential CCS industrial clusters and hubs across Brazilian regions,
Gustavo P. Oliveira, Beatriz R. Almeida, Thiago R. C. Justino, Carlos A. S. Santos, Alex A. Santos, Fabiana Philipi   +5 more
wiley   +1 more source

Automatic Representative View Selection of a 3D Cultural Relic Using Depth Variation Entropy and Depth Distribution Entropy

Entropy, 2021
Automatically selecting a set of representative views of a 3D virtual cultural relic is crucial for constructing wisdom museums. There is no consensus regarding the definition of a good view in computer graphics; the same is true of multiple views.
Sheng Zeng, Guohua Geng, Mingquan Zhou
doaj   +1 more source

Jacobi vector fields of integrable geodesic flows

, 1997
We show that an invariant surface allows to construct the Jacobi vector field along a geodesic and construct the formula for the normal component of the Jacobi field. If a geodesic is the transversal intersection of two invariant surfaces (such situation we have, for example, if the geodesic is hyperbolic), then we can construct a fundamental solution ...
Matveev, V. S., Topalov, P. I.
openaire   +3 more sources

Tropicalization of the Temperate Zone: Spatiotemporal Variability of Winter Warming and Declining Freeze Days Across the United States

International Journal of Climatology, EarlyView.
Unique characteristics of winter daily minimum (Tmin) and maximum (Tmax) temperatures and freeze days across the conterminous United States from 1952 to 2024 are examined. Results show spatial heterogeneity in Tmin/Tmax warming rates across the tropical‐temperate transition zone in the southeastern United States, and that the highest temperature on the
Vincent M. Brown, Derek T. Thompson, Buren B. DeFee II, Michael J. Osland, Barry D. Keim   +4 more
wiley   +1 more source