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A new approach for the design of wideband multilayer stacked patch antennas is proposed based on the bat algorithm. Differential topology is described for multilayer stacked patch antennas to achieve the stable and symmetry radiation patterns as well as the high cross-polarization (XP) suppression within the design band. The fabricated antenna prototypes show 25.5% and 34.9% impedance bandwidth for the two-layer and three-layer designs, respectively. The measured results validated the design. [ABSTRACT FROM AUTHOR]

An application of bat algorithm (BA) as a metaheuristic optimization approach in materials and design to an engineering problem has been presented in this paper. The purpose of the case study was to develop a new float as a part of measurement system according to the setup configuration and test environment. With this regard, several materials such as Acrylic, PVC, Nylon, Teflon (PTFE), and low-density polyethylene as feasible options for the float body in terms of mechanical, thermal, and chemical properties were selected. Then, optimal concurrent design of the float system with selected materials based on structural and performance constraints was addressed. For this purpose, the design was formulated into a constrained optimization problem and BA was used to find the optimal solutions in order to minimize the float length. The convergence of the design variables and constraints to optimal values was also investigated. Generalized reduced gradient method was used as well for validation and comparison of the BA results. It was found that the new optimal float had a pretty good performance in the test measurement. The results showed that BA can be a quite efficient approach to solve constrained optimization problems in materials and design. It is also suggested that the new float problem can be considered as a benchmark problem in materials and design to validate the robustness of the optimization algorithms. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this research is to compare the performance of Bat and Genetic Algorithm for the optimal conductor selection in radial distribution system for power loss minimization and voltage profile enhancement. Design/Methodology/Approach: The power flow model based on the load current, Bus Injected to Branch Current (BIBC), and Branch Current to Bus Voltage (BCBV) matrices was developed in MATLAB 2013b environment to compute the objective function. The implemented algorithms were validated on standard IEEE 33-bus radial distribution network, and tested on a 62-bus practical radial distribution network in Kaduna State Nigeria. Findings: The simulation results show that using Genetic Algorithm (GA) for an unbalanced distribution network, such as the one used in the case study, there is a reduced power loss of 19% and a voltage improvement of 1.3%. Using Bat Algorithm (BA), the reduced power loss is 26% with a voltage profile improvement of 1.9% when compared to the results of the network base-case. Research Limitation: The limitation of this research work is that it did not consider other IEEE bus systems like IEEE 4-bus and 62-bus systems. Originality/Value: The contribution of this research work is the use of BIBC and BCBV load flow analysis on BA and GA for the optimal conductor selection in IEEE 33-bus system and 62- bus system. The use has never been tested. The research findings contributes positively to the management of IEEE 33-bus radial distribution network. [ABSTRACT FROM AUTHOR]

A novel pattern of fractal antenna deploying Swastika slotted geometry up to second iteration is used for optimization in this paper which enhanced its utilities for S-band. Swastika Slotted Fractal Antenna has been designed and fabricated by the use of FR4 substrate material which has 1.6 mm as its substrate thickness, 4.4 as dielectric constant and 0.02 as loss tangent with help of Zeland IE3D software and MATLAB software. The comparison between Genetic Algorithm and Bat Algorithm revealed that results of BA are superior than GA for the designed geometry. The testing of proposed fabricated antenna has been done by using Rohde and Schwarz ZVL Vector Network Analyzer and obtained experimental results are in good agreement with optimized simulated results. Also, fabricated SSFA resonate at 2.49, 2.70, 2.96 and 3.96 GHz with corresponding values of S-parameter ( S ) as −16.78, −18.87, −28.66 and −11.48 dB respectively. [ABSTRACT FROM AUTHOR]

In this paper, seven different metaheuristic optimization algorithms developed between 2005 and 2012 are applied to optimize the robot trajectory for a three-revolute (3R) robotic arm. These algorithms include the artificial bee colony (ABC) algorithm, biogeography-based optimization, gravitational search algorithm, cuckoo search algorithm (CS), firefly algorithm, bat algorithm, and teaching–learning-based optimization (TLBO). This work presents the optimization problem with the objective to plan a trajectory, which can minimize joint travelling time, joint travelling distance, and total joint Cartesian lengths, simultaneously. Nine different design variables are considered for the intermediate joint angles, joint velocities, the end-effector angle for the final configuration, the time from initial to intermediate configuration, and the time from intermediate to final configuration. Two different experiments are conducted to investigate the effect of different considered metaheuristics: 1) for the free workspace and 2) for the workspace with obstacle. All these algorithms are compared based on the algorithm ability to find the best solutions, mean solutions, standard deviation, computational effort, and the convergence of the solutions. Statistical investigation is also performed by using the Friedman rank test and the Holm–Sidak multiple comparison $t$- test to check the significance of the algorithm for its suitability to the robot trajectory optimization problems. The results show the significance of TLBO, ABC, and CS for the robot trajectory optimization problems. [ABSTRACT FROM PUBLISHER]