This paper criticizes traditional models of urban–regional expansion, which depart from monocentric ideals urban core and ring. The original spatial-cycle model (SCM) suggests repeating stages urbanization, suburbanization, disurbanization re-urbanization. We reconceptualize the relations between core(s) ring(s) to test formation regions under mono-, multi- polycentric trajectories. analysis em...

The capacity of optical communication channels can be increased by space division multiplexing in structured fibers. Radial core fibers allows for the propagation twisted light–eigenmodes orbital angular momentum, which have attracted considerable attention high-dimensional quantum information. Here we study generation entangled photons that are tailor-made coupling into ring We show photon pai...

This work presents new evidence for conducive conditions the existence of overturning instabilities in mixed layer across a mesoscale anticyclonic Loop Current Eddy (LCE) and surrounding cyclonic eddies Gulf Mexico (GoM). The LCE was intensively sampled using four gliders during 12 months. is characterized by strong anomaly fresh warm water center strain at periphery. Mixed layers prone to are ...

Orbital angular momentum (OAM) mode division multiplexing (MDM) amplification in a seven-ring-core erbium-doped fiber (7-RC-EDF) has been experimentally demonstrated, which the 1 st -4 xmlns:xlink="http://www.w3.org/1999/xlink">th order OAM modes within each core of 7-RC-EDF can be support...

Various optical and dynamic light scattering studies have been conducted on the nematic phase of an oxazole-derived bent-core liquid crystal. At optical length scales and in the absence of applied fields, homogeneously aligned samples of this material, which has an oxazole heterocyclic ring in the central core, are found to behave more like a conventional straight-core nematic than a previously...

A practical hollow-core photonic crystal fiber design suitable for attaining low-loss propagation is analyzed. The geometry involves a number of localized elliptical features positioned on the glass ring that surrounds the air core and separates the core and cladding regions. The size of each feature is tuned so that the composite core-surround geometry is antiresonant within the cladding band ...

To improve the photophysical performance of colloidal quantum dots for laser applications, sophisticated core/shell geometries have been developed. Typically, a wider bandgap semiconductor is added as a shell to enhance the gain from the quantum-dot core. This shell is designed to electronically isolate the core, funnel excitons to it, and reduce nonradiative Auger recombination. However, the s...

the concept of fuzzy soft γ-ring is introduced; and some properties of fuzzy soft γ-rings are given. then the definitions of fuzzy soft γ-ideals are proposed and some of their theories are considered.