Results 31 to 40 of about 303,599 (157)

The phase portrait of the Hamiltonian system associated to a Pinchuk map

Anais da Academia Brasileira de Ciências
In this paper we describe the global phase portrait of the Hamiltonian system associated to a Pinchuk map in the Poincaré disc. In particular, we prove that this phase portrait has 15 separatrices, five of them singular points, and 7 canonical regions ...
JOAN CARLES ARTÉS, FRANCISCO BRAUN, JAUME LLIBRE   +2 more
doaj   +1 more source

From Charge‐Transfer Adducts to (Tri)Halide‐Templated Supramolecular Cages: Covalent vs Ionic Products in the Reactions of Pyridin‐4‐ylthio‐Substituted Tetrathiafulvalene With Dihalogens and Interhalogens

Chemistry – A European Journal, EarlyView.
The reactions between tetra(pyridin‐4‐ylthio)tetrathiafulvalene and Br2/I2/ICl/IBr led to a variety of products, including a rare example of neutral 1:4 CT adduct and ionic products showing supramolecular cage motifs at (tri)halide templates. The nature of the reaction products was elucidated based on XRD analysis, Raman spectroscopy and QTAIM, NCI ...
Anna Caria, Stéphane A. Baudron, M. Carla Aragoni, Vito Lippolis, Anna Pintus, Enrico Podda, Massimiliano Arca   +6 more
wiley   +1 more source

Lifestyle factors and lumbar disc disease: results of a German multi-center case-control study (EPILIFT) [PDF]

, 2010
Introduction: In the large-scale case-control study EPILIFT, we investigated the dose-response relationship between lifestyle factors (weight, smoking amount, cumulative duration of different sports activities) and lumbar disc disease.
Grifka, Joachim, Bergmann, Annekatrin, Joachim Grifka, Haerting, Johannes, Elsner, Gine, Martina Michaelis, Ulrich Bolm-Audorff, Annekatrin Bergmann, Ellegast, Rolf, Bolm-Audorff, Ulrich, Barbara Schumann, Rolf Ellegast, Gine Elsner, Seidler, Andreas, Ellegast, Rolf Peter, Jäger, Matthias, Schumann, Barbara,, Matthias Jäger, Schumann, Barbara, Andreas Seidler, Michaelis, Martina, Johannes Haerting   +21 more
core   +1 more source

Dynamic testing and analysis of turbine generator shafting

The Journal of Engineering, 2019
With the world's energy shortage, the scholars all over the world have done a lot of research work on the efficient use of energy, energy-saving emission reduction, and the development of new energy.
Changliang Tang, Liyong Wang, Tao Chen
doaj   +1 more source

Diffraction‐Free Natural Optical Skyrmions and Their Subwavelength Confinement Around Vortices

Laser &Photonics Reviews, EarlyView.
ABSTRACT Diffraction causes waves to spread out as they propagate freely. The tighter the lateral confinement, the faster the spreading. Past research on how to suppress diffraction has been based on wave engineering and has led so far to idealized waves that, in real settings, eventually diffract.
Nilo Mata‐Cervera, Deepak K. Sharma, Ramon Paniagua‐Dominguez, Yijie Shen, Miguel A. Porras   +4 more
wiley   +1 more source

Formalization of the Poincaré Disc Model of Hyperbolic Geometry

, 2020
International audienceWe describe formalization of the Poincaré disc model of hyperbolic geometry within the Isabelle/HOL proof assistant. The model is defined within the complex projective line ℂP1 and is shown to satisfy Tarski's axioms except for ...
Boutry, Pierre, Marić, Filip, Simić, Danijela   +2 more
core   +1 more source

Dual‐Metasurface‐Integrated Fiber Array for Bidirectional Cylindrical‐Vector‐Beam Multiplexed Communication Using Off‐Axis Spatial Manipulation

Laser &Photonics Reviews, EarlyView.
A dual‐layer metasurface is integrated on a fiber‐array facet to realize compact, plug‐and‐play free‐space optical links with cylindrical vector beam (CVB) space‐division multiplexing. An optimized off‐axis collimation layer steers multiple channels, while a Dammann vortex layer performs polarization–topology conversion for bidirectional CVB (de ...
Xipeng Lu, Jinke Li, Jin Tae Kim, Shaoyan Li, Hongliang Li, Duk‐Yong Choi, Sang‐Shin Lee   +6 more
wiley   +1 more source

Reconfigurable Geometric Phase Matching by Multilayered Nonlinear Thin‐Film Crystals

Laser &Photonics Reviews, EarlyView.
The concept of geometric phase matching is demonstrated as a dynamically reconfigurable approach for tunable nonlinear wave mixing in multilayered nonlinear thin‐film crystals. Experimental results reveal full modulation in a bilayer structure and near‐perfect spin‐selective phase matching of second‐harmonic generation in an eight‐layer configuration ...
Danielle Ben‐Haim, Mai Tal, Xiaoxi Xu, Tal Ellenbogen   +3 more
wiley   +1 more source

The measurement of the absolute displacement of a noisy disc brake [PDF]

, 2008
The investigation of in-plane vibration of a noisy disc brake is problematic because it is difficult both to measure and to verify. Because of the disc structure and the inability to visualize disc in-plane vibration, there has been reluctance by ...
Talbot, Chris J., Steel, William P., Fieldhouse, John D., J D Fieldhouse, W P Steel, C J Talbot   +5 more
core   +1 more source

Drive‐Efficient GHz‐Rate Binary‐State Updates Enabled by VCSEL Polarization Switching

Laser &Photonics Reviews, EarlyView.
Photonic computing needs a compact node that can hold a binary state and update it fast. A vertical‐cavity surface‐emitting laser biased at its polarization‐switching point could serve as one: its two orthogonal linear polarizations are the two states, and a small electrical drive is enough to move the output from one state to the other at gigahertz ...
Zifeng Yuan, Beibei Lin, Yutong Liu, Wujie Fu, Yuan Gao, Tingting Chen, Aaron Danner   +6 more
wiley   +1 more source