We investigate dispersion properties of a hexagonal dielectric periodic structure that can be used to engineer graded-index lenses. The connection between the geometry and its symmetries is explained. Furthermore, we demonstrate with increased symmetry more isotropic than conventional counterpart. To validate our analysis, designed, manufactured, measured planar Luneburg lens antenna. antenna h...

Energy absorption capability of thin-walled structures with various cross sections has been considered by researchers up to now. These structures as energy absorbers are used widely in different industries such as automotive and aerospace and protect passengers and goods against impact. In this paper, mechanical behavior of thin-walled aluminum tubes with and without polyurethane foam filler su...

Air-cleaved mica surfaces exhibit a high density of nanometer or micrometer size particles that have been ascribed to potassium carbonate formed as a reaction product of carbonaceous gases with potassium ions. Unambiguous evidence for this assignment has, however, never been presented. We study air-cleaved mica surfaces by high-resolution noncontact atomic force microscopy (NC-AFM) in ultrahigh...

This study investigated the effects of screwdriver handle shape, surface, and workpiece orientation on subjective discomfort, number of screw-tightening rotations, screw-insertion time, axial screwdriving force, and finger contact forces in a screwdriving task. Handles with three longitudinal cross-sectional shapes (circular, hexagonal, triangular), four lateral shapes (cylindrical, double frus...

The T-shaped amphiphilic molecule A6/6 forms a columnar hexagonal liquid-crystalline phase between the crystalline and the isotropic liquid when studied in bulk (Chen et al., 2005). Because of the hydrophilic and flexible oligo(oxyethylene) side chain terminated by a 1-acylamino-1-deoxy-d-sorbitol moiety attached to a rigid terphenyl core with terminal hexyloxy alkyl chains, it was expected tha...

Edge detection using a gradient-based detector is gold-standard method for identifying and analyzing different edge points in an image. A hexagonal grid structure powerful architecture dominant intelligent human-computer vision. This provides the best angle resolution, good packing density, high sampling efficiency, equidistant pixels, consistent connectivity. application on framework more accu...

Liquid crystalline materials comprised of a cyclic ring core and pendant triphenyl groups have been prepared. Differential scanning calorimetry (DSC) and polarized optical microscopy (POM) were utilized to identify the presence of the mesophases. X-ray diffraction (XRD) techniques confirmed that these liquid crystalline materials were discotic. The hexagonal nature of these triphenyl-based disc...

zno thin films with preferred orientation along the (002) plane were prepared onto the glass substrates by the sol-gel spin coating method for different post- annealing temperatures. the xrd study confirms that the thin films grown by this method have good crystalline hexagonal wurtzite structure. the optical band gap of the samples was determined from uv-visible spectra. it is found that the s...