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In this paper, a modified convex optimization technique is used for radiation pattern correction in a cylindrical‐shaped conformal microstrip array antenna. The technique uses numerical simulations to optimize the amplitude and phase excitations, with the goal to decrease the Euclidean distance between the desired field pattern and the obtained (simulated/measured) field pattern while maintaining the main beam direction, null's location, and side lobe levels under control. Two prototypes of 1×4 and 2×4 conformal microstrip antenna array deformed from linear/planar structure to the prescribed cylindrical shape, with different radii of curvature, are studied to demonstrate the performance of the proposed technique. The proposed convex optimization model when applied to conformal antenna array possesses fast computing speed and high convergence accuracy for radiation pattern synthesis, which can be a valuable tool for engineering applications. [ABSTRACT FROM AUTHOR]

Activated carbon was prepared from coconut coir and its ability to adsorb Reactive Yellow 15 (RY15) dye examined. Batch adsorption tests showed that the extent of dye adsorption depended on the initial dye concentration, the contact time and the pH value of the solution. Equilibrium adsorption was attained within 240 min, with maximum adsorption occurring at a pH value of 2. The adsorption capacity of the activated carbon towards the dye was evaluated and compared with that of a commercial activated carbon. Equilibrium adsorption data for the coconut coir activated carbon (CCAC) and the commercial activated carbon (CAC) were well described by the Langmuir and Freundlich isotherm models, and indicated the higher adsorption capacity of CCAC. The adsorption of RY15 by CCAC and CAC followed pseudo-secondorder kinetics. The results indicate that activated carbon prepared from coconut coir is more effective than CAC for the adsorption of RY15. Hence, CCAC would be a suitable substitute for CAC in the removal of Reactive dyes from aqueous solution. [ABSTRACT FROM AUTHOR]