In recent years reflectarray antennas have received considerable attention due to their unique capabilities. However, due to their large size, analyzing the performance of these antennas using traditional full wave finite-difference and finite-element techniques requires considerable computational resources. In this paper, we present an efficient method to accurately analyze these class of ante...

The introduction of new generations of mobile communication systems, such as the current 3G and the future 4G, along with the provision of multimedia services, has exponentially increased the number of users demanding higher data rate. This fact has aroused the interest in studying possible solutions to improve system performance without making use of new frequency band allocations in the alrea...

Wire electric discharge machine (WEDM) is spark erosion in unconventional machining technique to cut hard and the conductive material with a wire as an electrode. The blanking die material SKD 11 is a high carbon and high chromium tool steel with high hardness and high wearing resistance property. This tool steel has broad application in press tools and dies making industries. In this research ...

This paper addresses the design and development of HiperLAN antennas meeting the IEEE 802.11a standards for wearable applications. Five such antennas are investigated for their performance characteristics, out of which three are conventional copper based antennas and the remaining two are fully fabric antennas. The results reveal that all the proposed antennas are suitable for HiperLAN applicat...

We present a review of several types of microwave antennas made of metamaterials, including the resonant electrically small antennas, metamaterial-substrate patch antennas, metamaterial flat-lens antennas, and Luneburg lens antennas. In particular, we propose a new type of conformal antennas using anisotropic zero-index metamaterials, which have high gains and low sidelobes. Numerical simulatio...

High-gain and large-aperture antennas with fixed beams are required to achieve high S/N ratio for point-to-point high-speed data-communication systems in the millimeter-wave band. Furthermore, beam-scanning antennas are attractive to cover wide angle with high gain for applications of high-speed data-communication systems and high-resolution sensing systems. High-gain pencil-beam antennas are u...

introduction: any decrease in friction between orthodontic wire and bracket can accelerate tooth movement in the sliding technique and result in better control of anchorage. the present study was carried out to decrease this friction by coating of zinc oxide nanoparticles (zno) on orthodontic wires and porcelain brackets. materials and methods: in this in vitro study, a combination of 120 0.019...