Inert, spherical heterogeneities can pin three-dimensional scroll waves in the excitable Belousov-Zhabotinsky reaction. Three pinning sites cause initially circular rotation backbones to approach equilateral triangles. The resulting stationary shapes show convex deviations that increase with decreasing anchor radii. This dependence is interpreted as a transition between filament termination at ...

A meandered and a spiral stacked circular planar inverted–F antennas (PIFAs) are proposed for integration into head–implantable biomedical devices and wireless biotelemetry in the 402–405 MHz Medical Implant Communications Service (MICS) band. Designs only differ in the patch shape, feed, and shorting pin positions, while emphasis is given on miniaturization and biocompatibility. Phantom–relate...

A 16-station wear simulator of the pin-on-disc type, called RandomPOD, was designed, built, and validated. The primary area of application of the RandomPOD is wear studies of orthopaedic biomaterials. The type of relative motion between the bearing surfaces, generally illustrated as shapes of slide tracks, has been found to have a strong effect on the type and amount of wear produced. The compu...

A two-dimensional analytical solution is presented for stresses and displacements in an elastic curved beam forming incomplete ring frictionless unbonded contact with a rigid pin loaded by point force the presence of clearance. The circular modeled as thick ring, constrained at both ends plane stress state. displacement fields within are derived from biharmonic Airy function, according to Miche...

prostatic intra-epithelial neoplasia (pin) is considered a precursor of invasive carcinoma, characterized by proliferation and anaplasia of cells lining prostatic ducts and acini. in this study, we applied the pin grading system on one-hundred cases of prostatic carcinoma and one-hundred cases of benign prostatic hyperplasia, then compared the results. 74% of prostatic carcinoma and 51 % of pro...

Three-dimensional excitation vortices exist in systems such as chemical reactions and the human heart. Their one-dimensional rotation backbone can pin to unexcitable heterogeneities, which greatly affect the structure, dynamics, and lifetime of the vortex. In experiments with the Belousov-Zhabotinsky reaction, we demonstrate vortex unpinning from a pair of inert and impermeable spheres using ex...

This paper proposes a frequency/polarization reconfigurable antenna (RA) incorporating Frequency Selective Surface (FSS) to achieve dual-band and similar high-gain characteristics. The proposed RA-FSS design using 4 PIN Diodes can produce reconfigurability between circular polarization (CP) at 1.8 GHz linear (LP) 2.45 GHz. fabricated prototype shows good CP performance while the measured peak b...

This study focuses on perforated pin fin convection heat transfer. study's goal is to see if fins may help transmit heat. Perforation diameter and hole count are evaluated each pin. The Nusselt number of pins 47% higher than solid pins, it increases with perforation count. Unperforated have a 19% lower pressure drop. Using circular holes as sinks, we examined forced There were perforations. The...