Fixed Time Control and Synchronization for Perturbed Chaotic System Via Nonsingular Terminal Sliding Mode Method

This paper investigates the fixed time control and synchronization of chaotic system in the presence of compound disturbances. By using the definite integration and variable substitution, we present a new fixed time stability theorem for continuous nonlinear systems. In order to offset the bad effects of the compound disturbance, some novel sliding modes are constructed to improve the robustness of the controlled system and error system. For obtaining the robust controllers, some sufficient conditions of fixed time control and synchronization of the chaotic system are proposed by means of the sliding mode control method and the given stability theorem. Numerical simulation results are presented to verify and demonstrate the effectiveness of the proposed schemes.

Stationary random vibration of a viscoelastic Timoshenko cantilever beam under diverse random processes

In this paper, the stochastic properties of a uniform Timoshenko cantilever beam are investigated systematically. Based on the external viscous damping and Kelvin–Voigt viscoelastic damping, the partial differential equations of the Timoshenko beam subjected to random excitation are derived. The applied load is the concentrated force, and the excitation related to includes the ideal white noise, the band-limited white noise, and the exponential noise. Expressions are obtained for the space–time correlation functions and the space–frequency power spectral density functions of the transverse displacement response. The evident improvement is that the infinite integral and the definite integration in the mean square responses are worked out by means of the residue integral method and the integration by partial fraction, and the exact solutions of the mean square response are obtained in the form of an infinite series finally. This improvement provides a basis for both the mode truncation and the modal cross-spectral densities whether which can be ignored. Providing the numerical example, the numerical results obtained show the effectiveness of the theoretical analysis.

A critical approach proposal for training translation memory systems in translator education programs

The fast pace of todays translation market and the definite integration of translation memory systems TMS in the translators workstation have created new demands in terms of technological skills expected from novice translators. Aiming to prepare future translators to meet market demands, many translation undergraduate programs in Brazil have included the training on translation memory systems in their curricula. Applying the action-research methodology, this paper reports on the training methodology used for TMS in translation classrooms at two Brazilian public universities. The collected data in both contexts suggest that TMS may affect both the composing of the final translation and the decision-making of trainee translators and the quality of their production if they do not reflectively challenge their choices and the suggested output.

New approach to the calculation of pistachio powder hysteresis

Moisture sorption isotherms for pistachio powder were determined by gravimetric method at temperatures of 15, 25, 35 and 40°C. A selected mathematical models were tested to determine the best suitable model to predict isotherm curve. The results show that Caurie model had the most satisfactory goodness of fit. Also, another purpose of this research was to introduce a new methodology to determine the amount of hysteresis at different temperatures by using best predictive model of isotherm curve based on definite integration method. The results demonstrated that maximum hysteresis is related to the multi-layer water (in the range of water activity 0.2-0.6) which corresponds to the capillary condensation region and this phenomenon decreases with increasing temperature.