Different methods for network-based mobile positioning were compared experimentally. The Cell-id and TA method provided limited accuracy, the uncertainty ranging from 500 m to 3000 m for the median, dependant on area type. This could be reduced up to 25% by using alternative radii based on observations in the “doughnut” shaped prediction area. The Planning tool method improved the accuracy by a...

A previously developed theoretical procedure for determination of electromagnetic fields associated with the interaction of a higher-order Gaussian beam with a homogeneous spherical particle is used to investigate the effects of incident beam type on far-field scattering. Far-field scattering patterns are calculated for (0,0), (0,1), and (1,1) mode Hermite-Gaussian beams and for the helix dough...

Ultra-intense laser pulses with helical phases are of interest in laser-driven charged particle acceleration and related experiments extreme light. However, such optical vortices can be affected by the presence residual spatial-temporal couplings. Their field distributions after propagating free-space focal plane an ideal focusing mirror were assessed through numerical modeling, based on Gaussi...

BACKGROUND The time courses of retinal and choroidal thickness changes in dengue fever-associated maculopathy are not known. We measured central macular thickness (CMT), parafoveal retinal thickness (PRT), and subfoveal choroidal thickness (SCT), in one case, employing optical coherence tomography. FINDINGS The patient was a 43-year-old man diagnosed with dengue fever in Sri Lanka. He became ...

Abstract. How many maps with V vertices and E edges can be drawn on a doughnut with G holes? I solved this problem for doughnuts with up to 10 holes, and my colleagues Alain Giorgetti and Alexander Mednykh counted maps by number of edges alone on doughnuts with up to 11 holes. This expository paper outlines, in terms meant to be understandable by a nonspecialist, the methods we used and those u...

We report the observation of steady-state photorefractive vortex-screening solitons. As a singly charged circular vortex nested on a broad beam propagates through a biased strontium barium niobate crystal, it self-traps in both transverse dimensions despite the inherent anisotropy of the photorefractive nonlinearity. When the vortex beam is a doughnut-shaped narrow beam, it breaks up into two e...