Ion recombination is approximately corrected for in the Task Group 51 protocol by Pion, which is calculated by a two-voltage measurement. This measurement approach may be a poor estimate of the true recombination, particularly if Pion is large (greater than 1.05). Concern exists that Pion in high-dose-per-pulse beams, such as flattening filter free (FFF) beams, may be unacceptably high, renderi...

High Performance Fiber Reinforced Cementitious Composite (HPFRCC) materials exhibit strain hardening behavior with multiple cracking under tensile loading. In this paper, experimental and parametric studies are performed to assess the influence of using HPFRCC material instead of normal concrete in reinforced concrete beams. After calibrating the experimental results, the analytical results inc...

a reinforced concrete member in which the total span or shear span is especially small in relation to its depth is called a deep beam. in this study, a new approach based on the adaptive neural fuzzy inference system (anfis) is used to predict the shear strength of reinforced concrete (rc) deep beams. a constitutive relationship was obtained correlating the ultimate load with seven mechanical a...

Based on the ray transformation matrix formalism, we propose a simple method for generation of paraxial beams performing anisotropic rotation in the phase space during their propagation through isotropic optical systems. The widely discussed spiral beams are the particular case of these beams. The propagation of these beams through the symmetric fractional Fourier transformer is demonstrated by...

In this paper, we investigate the characteristics of a partially coherent flat-topped (PCFT) beam through turbulent atmosphere. The analytical expressions for the spectral density and the beam width of the astigmatic PCFT beams with circular symmetry propagating in turbulent atmosphere are derived. It is shown that the spectral density and beam width of these beams in turbulent atmosphere are h...

The present research studied the acoustic properties of 40 oak timber samples (Quercus castaneifolia): the acoustic coefficient (K) and acoustic conversion efficiency (ACE) in free vibration mode, using the free-free bar method with different planes of vibration, i.e., tangential (LT) and radial (LR). These acoustic parameters were considered for both primary virgin wooden beams and modified be...

We report the first observation of accelerating parabolic beams. These accelerating parabolic beams are similar to the Airy beams because they exhibit the unusual ability to remain diffraction-free while having a quadratic transverse shift during propagation. The amplitude and phase masks required to generate these beams are encoded onto a single liquid crystal display. Experimental results agr...

We investigated the scintillation properties of nonuniformly correlated (NUC) beams in atmospheric turbulence and have shown that NUC beams can not only have lower scintillation but also higher intensity than Gaussian-Schell model beams and even higher intensity than coherent Gaussian beams over certain propagation distances.

We demonstrate both theoretically and experimentally nonparaxial Mathieu and Weber accelerating beams, generalizing the concept of previously found accelerating beams. We show that such beams bend into large angles along circular, elliptical, or parabolic trajectories but still retain nondiffracting and self-healing capabilities. The circular nonparaxial accelerating beams can be considered as ...

We generate helical Ince-Gaussian (HIG) beams by using complex amplitude and phase masks encoded onto a liquid-crystal display (LCD). These beams display an intensity pattern consisting of elliptic rings, whose number and ellipticity can be controlled, and a phase exhibiting a number of in-line vortices, each with a unitary topological charge. We show experimental results that display the prope...