Development of ANFIS Control System for Seismic Response Reduction using Multi-Objective Genetic Algorithm

Adaptive neuro fuzzy inference system (ANFIS) and Genetic algorithm (GA) was proposed in this study to reduce dynamic responses of a seismically excited building. A multi-objective genetic algorithm (MOGA) was used to optimize the ANFIS+GA controller. Two MR dampers were used as multiple control devices and a scaled five-story building model was selected as an example structure. A fuzzy control algorithm was compared with the proposed ANFIS and ANFIS+GA controller. Adaptive neuro-fuzzy inference system (ANFIS) and Ganetic algorithm with several outputs was proposed. In case study, after numerical simulation, it has been verified that the ANFIS control algorithm can present better control performance compared to the fuzzy control algorithm in reducing both displacement and acceleration responses

Application of Evolutionary Algorithms in the Study of Fractional Order Electromagnetic Phenomena

The application of evolutionary algorithms in optimization is currently receiving growing interest from researchers with various backgrounds. A genetic algorithm (GA) is a search technique based on the natural selection process that provides a unique flexibility and robustness for process optimization. Recently, a closer look of some phenomena present in electrical systems and the motivation towards the development of comprehensive models, pointed out the requirement for a fractional calculus approach. In this work, it is applied the concept of fractional calculus to define, and to evaluate, the electrical potential of fractional order. Bearing these ideas in mind, the paper addresses the analysis and the synthesis of fractional-order multipoles, based in a GA optimization scheme.N/

Application of Fuzzy Control with Market-Based Control Strategy to Structures

The market-based control as a control strategy is developed based on an analogy between the control force-energy source in the structural area and the supply demand in the free market. The optimal problem of control force from an actuator is transformed to that of the allocation resource in the market. Since the supply-demand relation model and iteration procedure for the optimal price solution are necessary and relatively hard to understand and perform for civil engineers, the fuzzy logical method is proposed in the framework of the market-based control to acquire an equivalent system corresponding to the market-based control method. An equivalent fuzzy logical rule is established through analyzing a single-degree-of-freedom system with the controller using the MBC strategy under earthquakes. The results show that the fuzzy logical method is able to also reduce the displacement and acceleration responses effectively similar to the MBC method, and the consumed computational time for the fuzzy logical method is obviously saved

Fuzzy Control for Seismic Protection of Semiactive Base-Isolated Structures Subjected to Near-Fault Earthquakes

This paper proposes a new fuzzy logic controller, which is designed for seismic protection of base-isolated structures utilizing piezoelectric friction damper against near-fault earthquakes for different ground sites. According to the elastic design spectrum that Eurocode 8 recommends, one 5% damped elastic design spectrum for Chi-Chi earthquake is proposed to generate artificial earthquakes of different ground sites. The proposed controller employs a hierarchic fuzzy control algorithm, in which a supervisory fuzzy controller governs a sublevel fuzzy controller by altering its input normalization factors according to current level of ground motion. In order to simultaneously reduce the base displacement and superstructure responses of the base-isolated structure during seismic excitations, genetic algorithm is employed to optimize the supervisory fuzzy controller and the preload of piezoelectric friction damper. The efficiency of the proposed controller is also compared with passive controller and a linear quadratic Gauss optimal controller. Numerical results show that the proposed fuzzy logic controller has favorable performance in mitigating the responses of the base-isolated structure