Optimization of Ultra wide Band Communication TCA and AVA by using PSO and IGWO-FU Algorithm

Recently, with the faster pace of development on the sophisticated detection and stealth technology, an extensive attention is being paid to the reduction of Radar Cross Section (RCS) as it emerge in security and commercial application. Communication based applications have greater influence depends upon design architecture and performance of an antenna. This paper proposed FSS to triumph over varying values as considering design parameters. Here, Frequency Selective Surface (FSS) is optimized with a technique said to be Particle Swarm Optimization (PSO), used for tightly coupled array (PSO-UTC-FSS). This paper intends to design an Optimized Vivaldi antenna to enhance the gain performance. More particularly, optimization algorithms play a vital role in fine-tuning of parameter, and hence this paper intends to propose a new Improved Grey Wolf Optimization Algorithm with Fitness based Update evaluation (IGWO-FU), which is the enhanced version of traditional GWO. Using above concepts, losses are minimized and hence it improves radiation efficiency, gain measurement, bandwidth ratio etc. Finally, the performance of proposed IGWO-FU model is compared over other traditional algorithms with respect to gain, VSWR, directivity, charge and current distribution, return loss as well.

Design and Analysis of Multiband Bloom Shaped Patch Antenna for IoT Applications

A Microstrip Bloom shaped patch antenna is proposed for Internet of Things (IoT) application. This antenna operates at multiband frequencies between 1.6 GHz to 2.45 GHz. The Bloom shaped antenna provides multiband response that examined in HFSS Software. In this proposed antenna design, FR4 substrate material is used because it is easily available and low cost. The proposed antenna structure simulated and analyzed in different experimental results including return loss measurement, Voltage Standing Wave Ratio measurement, radiation pattern measurement and gain measurement. This proposed Multiband Microstrip Bloom shaped patch antenna provides better experimental results in all the parameters

A method for EMCCD multiplication gain measurement with comprehensive correction

In order to improve the image quality, it is imperative to conduct the non-uniformity correction of EMCCD, for which the measurement accuracy of the internal electron multiplication gain of each channel is a prerequisite within multi-channel output EMCCD. It is known that the smaller the image standard deviation of each channel, the better the image uniformity, and the closer the calculated multiplier gain is to the real value. In order to minimize the influence of non-uniformity of background between pixels and light response existing in traditional measurement, a comprehensively modified EMCCD multiplication gain measurement is proposed after the working principle of EMCCD is described. The output images of the camera working in the normal CCD mode and EMCCD mode are corrected comprehensively through this method. The experimental results show that after the comprehensive correction, the standard deviation of the output image of each channel within the camera decreases to about one third of the original when the camera works in the normal CCD mode, while it decreases to about one fifth of the original when the camera works in the EMCCD mode, the signal stability is significantly improved, and the measured multiplier gain of each channel is closer to the true value of the detector, which proves the effectiveness of the proposed method.

Investigating the learning perspective of Searching as Learning, a review of the state of the art

Current search engines are not designed to facilitate learning as they do not lead the user to develop more complex skills. Searching as Learning (SAL) emerged as a research area from the intersection of information search and learning technologies in order to advance the study of searching as a learning process. However, we wonder how have the learning theories and approaches been explored in SAL. Through a systematic review of the literature, we identified 65 papers that report SAL solutions. We analyzed them, seeking to answer (i) which learning theories, approaches and methods support the searching as a learning process, and (ii) what metrics, procedures, or treatments were used to measure learning during the searching process. We uncover the learning perspective in the SAL literature, discussing the learning paradigms, the mechanisms influencing the learning process, the search session design for learning and the knowledge gain measurement strategies.

Effects of the Different Solid Deposits on the Corrosion Behavior of Pure Fe in Water Vapor at 500°C

A comprehensive corrosion investigation of pure Fe in an environment of solid sodium salt deposit (i.e., NaCl or Na2SO4) with mixtures of H2O and O2 at 500°C was conducted by mass gain measurement, X-ray diffraction (XRD), scanning electron microscope (SEM), potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). The results showed that corrosion rates were accelerated with solid NaCl or Na2SO4 deposit due to their reaction with the formed protective scale of Fe2O3 and subsequently resulted in its breakdown. The corrosion rate of pure Fe with solid NaCl is higher than that with solid Na2SO4 because of the lower activation energy (Ea) for chemical reaction of Fe in solid NaCl+H2O+O2 (i.e., 140.5 kJ/mol) than that in solid Na2SO4+H2O+O2 (i.e., 200.9 kJ/mol). Notably, the electrochemical corrosion rate of pure Fe with solid NaCl deposit, 1.16×10−4 A/cm2, was a little lower than that with solid Na2SO4 deposit.

Horn Antenna

One of the simple and most widely used microwave antennas is the horn as a feed element for large radio telescopes, satellite tracking, and communication reflector, which are found installed throughout the world. In addition to its utility as a feed for reflectors and lenses, it is a common element of phased arrays and serves as a universal standard for calibration and gain measurement of other high gain antennas. Its widespread applicability stems from its simplicity in construction, ease of excitation, large gain, wide-band characteristics, and preferred overall performance. An electromagnetic horn can take many different forms, such as basic pyramidal, conical, corrugated, double-ridged, and dual polarized horns, as well as horns with lens and so on. The horn is nothing more than a hollow pipe of different cross-sections, which has been tapered to a larger opening aperture. This chapter explains the fundamentals of the pyramidal horn antenna in detail using aperture field method. Numerical and measured examples, are also shown.