Results 131 to 140 of about 111,827 (288)

Closed conformal vector fields

Journal of Differential Geometry, 1969
Tanno, Shûkichi, Weber, Waldemar C.
openaire   +2 more sources

On Conformal Vector Fields Parallel to The Observer Field

, 2008
We review a theorem by Hasse and Perlick establishing a result characterizing parallax-free cosmological models via three equivalent properties -- namely the existence of a redshift potential, the existence of a conformal vector field parallel to the observer field, and the vanishing of the shear of the observer field together with some integrability ...
Dirmeier, Alexander, Plaue, Matthias, Scherfner, Mike   +2 more
openaire   +2 more sources

Optoelectronically Active GaAs/GeSn‐MQW/Ge Heterojunctions Created via Semiconductor Grafting

Advanced Optical Materials, EarlyView.
Semiconductor Grafting enables a lattice‐mismatched GaAs/GeSn‐MQW/Ge heterojunction with engineered band offsets and optical field distribution. The enlarged conduction and valence band discontinuities govern asymmetric carrier transport, producing bias‐dependent dual‐mode photodetection from visible to near‐infrared wavelengths.
Jie Zhou, Haibo Wang, Yang Liu, Yifu Guo, Alireza Abrand, Yiran Li, Jiarui Gong, Hieu D. Trinh, Po Rei Huang, Jianping Shen, Shengqiang Xu, Daniel Vincent, Samuel Haessly, Yi Lu, Munho Kim, Shui‐Qing Yu, Parsian K. Mohseni, Guo‐En Chang, Zetian Mi, Kai Sun, Xiao Gong, Mikhail A. Kats, Zhenqiang Ma   +22 more
wiley   +1 more source

2-conformal and conformal vector fields on Riemannian manifolds

Filomat
In this paper, we study 2-conformal vector fields on Riemannian manifolds. Some relations between 2-conformal vector fields, conformal vector fields, Killing and 2-Killing vector fields have been obtained. Also, relation between monotone vector fields and 2-conformal vector fields is investigated.
Ghodratallah Fasihi-Ramandi, Uday De, Shahmkhali Farzaneh   +2 more
openaire   +1 more source

Foliations Transverse to a Closed Conformal Vector Field

Results in Mathematics
In this article, we study the geometric properties of codimension one foliations on Riemannian manifolds equipped with vector fields that are closed and conformal. Apart from its singularities, these vector fields define codimension one foliations with nice geometric features, which we call Montiel Foliations.
Euripedes da Silva, Ícaro Gonçalves, Júlio Pereira   +2 more
openaire   +3 more sources

Materials for Suppressed Triplet‐Polaron Quenching in Efficient and Long‐Lifetime Phosphorescent OLEDs

Advanced Optical Materials, EarlyView.
We performed a computational screening of phosphorescent emitters and charge transporters for OLEDs to identify combinations that minimize triplet‐polaron quenching, a major cause of efficiency loss and short operational lifetimes, especially in blue OLEDs. Our results reveal key design rules and highlight emitter‐transporter pairs that strongly reduce
Clint van Hoesel, Reinder Coehoorn, Peter A. Bobbert   +2 more
wiley   +1 more source

Hard‐Magnetic Soft Millirobots in Underactuated Systems

Advanced Robotics Research, EarlyView.
This review provides a comprehensive overview of hard‐magnetic soft millirobots in underactuated systems. It examines key advances in structural design, physics‐informed modeling, and control strategies, while highlighting the interplay among these domains.
Qiong Wang, Zixuan Zhang, Bingyan Li, Junkai Wang, Hongcheng Gu   +4 more
wiley   +1 more source

ChicGrasp: Imitation‐Learning‐Based Customized Dual‐Jaw Gripper Control for Manipulation of Delicate, Irregular Bio‐Products

Advanced Robotics Research, EarlyView.
Automated poultry processing lines still rely on humans to lift slippery, easily bruised carcasses onto a shackle conveyor. Deformability, anatomical variance, and hygiene rules make conventional suction and scripted motions unreliable. We present ChicGrasp, an end‐to‐end hardware‐software co‐designed imitation learning framework, to offer a ...
Amirreza Davar, Zhengtong Xu, Siavash Mahmoudi, Pouya Sohrabipour, Chaitanya Pallerla, Yu She, Wan Shou, Philip Glen Crandall, Dongyi Wang   +8 more
wiley   +1 more source

Analyticity and the Unruh effect: a study of local modular flow

Journal of High Energy Physics
The Unruh effect can be formulated as the statement that the Minkowski vacuum in a Rindler wedge has a boost as its modular flow. In recent years, other examples of states with geometrically local modular flow have played important roles in understanding
Jonathan Sorce
doaj   +1 more source

Liquid Crystalline Elastomers in Soft Robotics: Assessing Promise and Limitations

Advanced Robotics Research, EarlyView.
Liquid crystalline elastomers (LCEs) are programmable soft materials that undergo large, anisotropic deformation in response to external stimuli. Their molecular alignment encodes directional actuation in a monolithic structure, making them long‐standing candidates for soft robotic systems.
Justin M. Speregen, Timothy J. White
wiley   +1 more source