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•With a shorter settling time and a better tracking response than previous MPPT algorithms, the suggested ASOA-based fuzzy IC MPPT controllers can reach the MPP more quickly. Furthermore, with an average power harvesting efficiency of over 97.9 %, ASOA-based fuzzy IC MPPT controllers offer the best harvesting characteristics.•The traditional P&O method does not exhibit excellent transient behavior, according to a thorough comparison that was undertaken for all simulated situations between the classical and modified MPPT algorithms.•Temperature fluctuations have an effect on the proposed ASOA-based FOCV MPPT, as demonstrated in scenarios 3 and 4. Therefore, under these conditions, it has poor harvesting qualities with low average power, E.A, and A.F.F values.•In terms of a small number of iterations, quick calculation, and rapid convergence to the optimum solution, the suggested ASOA is more effective than PSO in obtaining optimal control parameters for achieving MPPT.

The design of classical controllers for Voltage Source Converter High Voltage Direct Current (VSC-HVDC) transmission systems, is load-dependent and has to be adjusted for each operating condition. Thus, the robustness of such controllers becomes necessary to cope with operating condition continuous variations. Therefore, the design of hybrid optimal Artificial Intelligence Based-Sliding Mode Controllers (AI-SMCs) for VSCHVDC transmission systems is crucial research interest. These AI based controllers are proved to improve the system's dynamic stability over a wide range of operating conditions considering different parameter variations and disturbances. For this purpose, a comprehensive state of the art of the VSC-HVDC stabilization dilemma is discussed. The nonlinear VSC-HVDC model is developed. The problem of designing a nonlinear feedback control scheme via two control strategies is addressed seeking a better performance. For ensuring robustness and chattering free behavior, the conventional SMC (C-SMC) scheme is realized using a boundary layer hyperbolic tangent function for the sliding surface. Then, the Modified Genetic Algorithm (MGA) and Particle Swarm Optimization technique (PSO) are employed for determining the optimal gains for such SMC methodology forming a modified nonlinear MGA-SMC and PSO-SMC control in order to conveniently stabilize the system and enhance its performance. The simulation results verify the enhanced performance of the VSC-HVDC transmission system controlled by both MGA-SMC and PSO-SMC compared to the C-SMC. The comparative dynamic behavior analysis for both the conventional SMC and the two meta-heuristic optimization based SMC control schemes are presented. Through simulation results, the effectiveness of the proposed metaheuristic optimization approaches and their applicability to VSC-HVDC system global stabilization and dynamic behavior enhancement are validated. • Nonlinear feedback control scheme for VSC-HVDC transmission system. • Sliding Mode Control for system dynamic performance and stability improvement. • Metaheuristic techniques for optimizing the Sliding Mode Control gains. • Comparative study between the conventional SMC and the optimized-SMCs. [ABSTRACT FROM AUTHOR]

In this work, factors that affect removal of zinc ion from aqueous solution by activated carbon were evaluated using the response surface methodology. The effects of concentration, pH, and activated carbon/solution ratio on removal efficiency were considered, and optimum conditions were determined. Then, the kinetics and equilibrium equations were expressed. Maximum removal efficiency for zinc in batch tests reached 96.7%. Moreover, co-adsorption of zinc and nickel ions was studied. Zn removal efficiency when Ni ions were present was enhanced surprisingly. Also, single Zn, as well as a system containing Zn and Ni ions, removal in a permeable reactive barrier was investigated. Single zinc breakthrough time reached 60 h, while similar breakthrough in a system containing Zn and Ni ions reached 65 h. Finally, various regeneration tests were conducted with over 90% desorption efficiency.

•Wind energy conversion system was constructed and simulated in this study.•This paper presents design for robust optimal PID based blade pitch control of a wind power plant.•Comprehensive analysis study for PID based pitch control was performed.•The system under all possible normal and abnormal situations was examined.

This paper numerically investigates flexural performance of Ultra-High Performance Concrete (UHPC) beam reinforced with Steel-Fibre-Reinforced Polymer (FRP) Composite Bars (SFCBs) in terms of flexural stiffness, moment capacity, deflection, ductility and energy dissipation. The effect of various parameters, include the inner steel core area ratio of SFCB, yield strength of inner steel core, elastic modulus and ultimate strength of outer-wrapped FRP, reinforcement ratio, type and strength of concrete were studied. The results demonstrate that the inner steel core area ratio of SFCB, reinforcement ratio and the elastic modulus of SFCB's outer FRP have significant effect on the overall flexural performance of SFCB reinforced UHPC beam. The overall flexural performance of SFCB reinforced UHPC beam is slightly improved by increasing the yield strength of inner steel core of SFCB, but not affected by the ultimate strength of SFCB's outer FRP when specimen occurred compression failure. The results also exhibit that the flexural performance of UHPC beam reinforced with SFCBs is significantly improved when compared to those of reinforced high strength concrete (HSC) beam and normal strength concrete (NSC) beam. The flexural stiffness and the moment capacity of SFCB reinforced UHPC beam at the ultimate point were 2.0 and 2.4 times, respectively, of those of reinforced NSC counterpart.

Three specimens of composite beams were tested under a four-points bending test to study the effect of BFRC height on the flexural behavior of the composite beam. The numerical software MATLAB was used to numerically study the bending moment-curvature (M-φ) relationship of the composite beams. The finite element software (ABAQUS) was used to simulate the flexural behavior of the composite beams, and the parameter analysis is carried out to study the effect of strength and height of BFRC, strength and ratio of steel reinforcement on the flexural performance of BFRC-concrete composite beams. The study results show that the flexural capacity of the composite beam is higher than that of the normal concrete beam. With the increase of the height of the BFRC, the flexural capacity increases, and the bottom crack propagation is significantly inhibited. The BFRC height has a negligible effect on the ductility of the composite beam. The results illustrate the assumption of the plane section is valid, and the bonding behavior between steel bar and BFRC as well as the co-working between BFRC and ordinary concrete are perfect. Based on the experimental results, formulae are developed for predicting the cracking, yield, and ultimate moment bearing capacity of the composite beam, and a simplified formula is also developed for predicting the ultimate bearing capacity of composite beam with a balanced reinforcement ratio. The prediction results are consistent well with the test results, and the simulation results exhibit a good agreement with the test results of composite beams.