Results 61 to 70 of about 2,960 (265)

A CLASS OF FOUR-DIMENSIONAL WARPED PRODUCTS [PDF]

Demonstratio Mathematica, 2002
The authors investigate properties of 4-dimensional warped product manifolds satisfying a particular set of curvature conditions. As an application, it is obtained a generalization of a pseudosymmetric property for Ricci-flat warped product spacetimes which was established previously in some special cases, including the Schwarzschild metric.
Defever, F., Deszcz, R., Głogowska, M., Goldberg, V. V., Verstraelen, L.   +4 more
openaire   +2 more sources

Wood‐Derived Nanocellulose‐Biocarbon Fresnel‐Zone Plate Lenses for Sub‐THz Frequency Applications

Advanced Materials Technologies, EarlyView.
Wood‐derived nanocellulose and lignin‐based biocarbon were combined to fabricate fully bio‐based Fresnel zone plate (FZP) lenses for sub‐terahertz frequencies. These sustainable FZP lenses exhibit low dielectric loss and high directivity, achieving performance comparable to that of metallic references, and remain functional under environmental stress ...
Riikka Haataja, Mikko Kokkonen, Niina Halonen, Sami Myllymäki, Umair Rafique, Mandeep Singh, Ossi Laitinen, Heli Jantunen, Kristiina Oksman, Henrikki Liimatainen   +9 more
wiley   +1 more source

Warped Product Pseudo-Slant Submanifolds of a Nearly Cosymplectic Manifold

Abstract and Applied Analysis, 2012
We study warped product pseudo-slant submanifolds of a nearly cosymplectic manifold. We obtain some characterization results on the existence or nonexistence of warped product pseudo-slant submanifolds of a nearly cosymplectic manifold in terms of the ...
Siraj Uddin, Bernardine R. Wong, A. A. Mustafa   +2 more
doaj   +1 more source

Deterministic Integration of Quantum Emitters and Optical Cavities in a Van Der Waals Crystal

Advanced Optical Materials, EarlyView.
The work demonstrates fabrication of Circular Bragg Grating (CBG) cavities with embedded emitters in hBN. The cavities are fabricated around a pre‐characterised quantum emitter. The integrated platform enables light matter interaction and access to brighter emitters and spins in hBN.
James Liddle‐Wesolowski, Otto Cranwell Schaeper, Nathan Coste, Benjamin Whitefield, Evan Williams, Helen Zhi Jie Zeng, Mehran Kianinia, Anastasiia Zalogina, Igor Aharonovich   +8 more
wiley   +1 more source

Homology Groups in Warped Product Submanifolds in Hyperbolic Spaces

Journal of Mathematics, 2021
In this paper, we show that if the Laplacian and gradient of the warping function of a compact warped product submanifold Ωp+q in the hyperbolic space ℍm−1 satisfy various extrinsic restrictions, then Ωp+q has no stable integral currents, and its ...
Yanlin Li, Akram Ali, Fatemah Mofarreh, Nadia Alluhaibi   +3 more
doaj   +1 more source

The Weyl problem in warped product spaces

Journal of Differential Geometry, 2020
In this paper, we discuss the Weyl problem in warped product space. We obtain the openness, non rigidity and some applications. These results together with the a priori estimates obtained by Lu imply some existence results. Meanwhile we reprove the infinitesimal rigidity in the space forms.
Li, Chunhe, Wang, Zhizhang
openaire   +3 more sources

Improving the Robustness of Visual Teach‐and‐Repeat Navigation Using Drift Error Correction and Event‐Based Vision for Low‐Light Environments

Advanced Robotics Research, EarlyView.
Visual teach‐and‐repeat (VTR) navigation allows robots to learn and follow routes without building a full metric map. We show that navigation accuracy for VTR can be improved by integrating a topological map with error‐drift correction based on stereo vision.
Fuhai Ling, Ze Huang, Tony J. Prescott
wiley   +1 more source

The base of warped product submanifolds of Sasakian space forms characterized by differential equations

Advances in Difference Equations, 2021
In the present paper, we find some characterization theorems. Under certain pinching conditions on the warping function satisfying some differential equation, we show that the base of warped product submanifolds of a Sasakian space form M ˜ 2 m + 1 ( ϵ )
Akram Ali, Ravi P. Agrawal, Fatemah Mofarreh, Nadia Alluhaibi   +3 more
doaj   +1 more source

Muscle Control of an Extra Robotic Digit

Advanced Robotics Research, EarlyView.
This study compares muscle‐ and movement‐based control for operating a supernumerary robotic thumb. While movement control performs better in the proposed tasks, muscle‐based (EMG) control promotes broader motor learning. The results highlight the promise and challenges of using biosignals for human augmentation, offering new insights into intuitive ...
Julien Russ, Lucy Dowdall, Francesco Cenciarelli, Kitty Goodridge, Mabel Ziman, Hristo Dimitrov, Danielle Clode, Tamar R. Makin   +7 more
wiley   +1 more source

Levi-Civita Ricci-Flat Doubly Warped Product Hermitian Manifolds

Advances in Mathematical Physics, 2022
Let M1,g and M2,h be two Hermitian manifolds. The doubly warped product (abbreviated as DWP) Hermitian manifold of M1,g and M2,h is the product manifold M1×M2 endowed with the warped product Hermitian metric G=f22g+f12h, where f1 and f2 are positive ...
Qihui Ni, Yong He, Jinhua Yang, Hui Zhang   +3 more
doaj   +1 more source