We report on the backscattering induced by sidewall roughness in silicon on insulator optical nanowires, its dependence on the waveguide geometrical and optical parameters and its impact on silicon photonic devices. In silicon ring resonators cavity-enhanced backscattering, increasing with the square of the resonator’s finesse, emerges as a severe

Background: Monte Carlo simulations play a vital role in the calculation of the necessary shielding both for neutrons and photons. Advanced and simple shielding materials against neutron and gamma rays were compared by simulation using the MCNB4B Monte Carlo code. The simulations were carried out for the three common neutron sources, namely the 252Cf, the 241Am/Be and the DD neutron generator w...

Neutron dose-equivalent buildup factors were calculated for point isotropic neutron sources irradiating infinite slablike shields of lead, iron and water using the MCNP code. The factors are presented for some source neutron energies in the range from 0.025 eV to 14 MeV, and for shield thicknesses from 0.5 to 10 mfp. Since the MCNP code considers all kinds of neutron interactions with matter, a...

We found that the coherent backscattering cone of turbid samples containing spherical Mie scatterers with a size parameter larger than about 20 strongly deviates from known analytical curve shapes. We compare experimental data with numerical simulations of Monte Carlo type. Moreover, we present a new wide-angle coherent backscattering set-up.

A digital method of calculating the radar backscattering diagrams is presented. The method uses a digital model of an arbitrary scattering object in the 3D graphics package " OpenGL " and calculates the backscattered signal in the physical optics approximation. The backscattering diagram is constructed by means of rotating the object model around the radar-target line.

Measurements include near forward optical scattering (providing information of cross-sectional area, and thus size, of aggregates, LISST, Sequoia Scientific), optical transmission and backscattering (WET Labs’ BB(RT)) and acoustical backscattering at 4.5MHz ( Nortek’s VECTOR). Concentrations of clays are siphoned out from the sampling volumes of the sensors and measured using suspended sediment...

introduction bnct is an effective method to destroy brain tumoral cells while sparing the healthy tissues. the recommended flux for epithermal neutrons is 109 n/cm2s, which has the most effectiveness on deep-seated tumors. in this paper, it is indicated that using d-t neutron source and optimizing of beam shaping assembly (bsa) leads to treating brain tumors in a reasonable time where all iaea ...

In this work, X band images acquired by COSMO-SkyMed (CSK) on alpine environment have been analyzed for investigating snow characteristics and their effect on backscattering variations. Preliminary results confirmed the capability of simultaneous optical and Synthetic Aperture Radar (SAR) images (Landsat-8 and CSK) in separating snow/no-snow areas and in detecting wet snow. The sensitivity of b...