Abstract-There are various noisy non-linear mathematical optimization problems that can be effectively solved by Metaheuristic Algorithms. These are iterative search processes that efficiently perform the exploration and exploitation in the solution space, aiming to efficiently find near optimal solutions. Considering the solution space in a specified region, some models contain global optimum and multiple local optima. In this context, two types of meta-heuristics called Particle Swarm Optimization (PSO) and Firefly algorithms were devised to find optimal solutions of noisy non-linear continuous mathematical models. Firefly Algorithm is one of the recent evolutionary computing models which is inspired by fireflies behavior in nature. PSO is population based optimization technique inspired by social behavior of bird flocking or fish schooling. A series of computational experiments using each algorithm were conducted. The results of this experiment were analyzed and compared to the best solutions found so far on the basis of mean of execution time to converge to the optimum. The Firefly algorithm seems to perform better for higher levels of noise.

This paper present particle swarm optimization(PSO) based design of a single band H-shape microstrip patch antenna using HFSS and curve fitting. A shape H of the patch is used to express optimization technique. PSO technique used to obtain geometry parameter for effective antenna performance. The performance of conventional antenna is compare with the performance of PSO optimized antenna. In the Result show that PSO optimized antenna resonance exactly at 2.4Ghz and also improvement in bandwidth from 16.10% to 18.22%.

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In this communication, the structural and electrical properties of metal-ferroelectric-insulator-silicon (MFIS) capacitor structure have been reported for non-volatile memory applications. Sol-gel with spin coating and rf sputtering process have been used for depositing BiFeO 3 (BFO) and ZrO 2 films, respectively. It has been observed that BFO film shows pure ferroelectric phase, uniform grain size and maximum refractive index at annealing temperature of 500 °C. Thermo-gravimetric analyzer and differential scanning calorimetry analysis indicate good agreement with X-ray diffraction of BFO film. In ZrO 2 thin film, it has been observed that ZrO 2 is in amorphous state at all annealing temperatures and the maximum refractive index has been found at annealing temperature of 400 °C. Al/ZrO 2 /n-Si (MIS), Al/BiFeO 3 /n-Si (MFS) and Al/BiFeO 3 /ZrO 2 /n-Si (MFIS) structures have been fabricated to investigate the electrical characteristics. The memory window has been observed by capacitance-voltage (C-V) characteristics and it improves from 1.9 V in MFS structure to 5.4 V in MFIS structure with 8 nm dielectric layer. Leakage current density has been observed by current density-gate voltage (J-V) characteristics and it is order of 10 −5 A/cm 2 in MF 150 nm I 8 nm S structure. No charge value degrades up to 10 12 iteration cycles in MF 150 nm I 8 nm S structure.

Dielectric resonator (DR) antenna is a more useful antenna in the last twenty years, due to its various attractive characteristics (like low profile, high gain, high radiation efficiency, and low metallic losses at high frequency) [1]. DR has some fundamental shape like rectangular, cylindrical, and spherical but some modified shapes also possible like a disk, ring, triangular, half-split, notch rectangular, conical, and elliptical [1,2]. Last few years, many researchers focus on the enhancement of bandwidth with a different method like ring shape DR, multi-segment DR, and adopted hybrid feeding structure in DRA [3,4]. Main objective behind this method is the enhancement of bandwidth (30-75%) by reducing Q-factor. The Q-factor is reduced by placing DR above the ground plane [4][5][6].In the present age of wireless communication, we are more focused on circular polarization (CP) because it has removed the disadvantage of linear polarization (LP). The main disadvantaged of linear polarization is multiple-path between transmitting and receiving antenna and misalignment between them [7]. There are many techniques which can be used to achieve CP (like difference shape of dielectric resonator with various feeding mechanism, two orthogonal electric field components, or 90°p hase difference between these field components). Wideband antenna is more useful in cogitative radio applications [8][9][10].