Like other offshore structures, floating wind turbines are subjected to stochastic wave and wind loads that cause a Dynamic Response in the structures. Wind turbines should be designed for different conditions, such as Operational and Survival conditions. In high sea states, the Response can be quite different from the operational condition. The present paper deals with coupled wave and wind induced motion in harsh conditions, up to 15 m significant wave height and 50 m/sec average wind speed. There are several ways to deal with the Dynamic Response of floating wind turbines. The Coupled Time domain Dynamic Response analysis for a moored spar wind turbine subjected to wave and wind loads is carried out using DeepC. DeepC is well known software for calculating the coupled Dynamic Response of moored floating structures. The aeroDynamic forces on a parked wind turbine are calculated, based on the strip theory, and imported to the DeepC through a MATLAB interface. At each time step, the relative wind velocity, based on the Response of the structure, is calculated.

In this research, the Dynamic Response and vibration control of a sandwich piezoelectric cylindrical shell buried in an elastic medium under the effect of a moving ring load has been investigated. First, the Dynamic equations of the shell are obtained based on Love's thin-walled shell theory, and then they are coupled with the governing equations of the surrounding elastic medium. Then, the resulting differential equations are solved using the Fourier transform, and after using Gauss's numerical integral for the inverse Fourier transform, the steady state Dynamic Response of the system is obtained. To reduce the vibrations caused by the moving load, a PID controller with optimized constants has been used. With extensive research done, the innovation presented in this research is the active reduction of the level of vibrations of a smart buried shell (pipe, tunnel) under the effect of a moving applied load. In a way, this innovation is at the same time being buried in the unlimited elastic environment and the piezoelectricity of the shell. The results show that the implemented controller is able to reduce the displacement range and stress in the system. Also, the operation of the piezoelectric active layer based on the appropriate controller reduces the sensitivity of the system to parameter changes.

Due to the lack of measurements in many regions, wave characteristics are estimated using different methods. Wave climate hindcasting/forecasting is mostly conducted by numerical models or empirical methods. Until now, different empirical methods have been developed for wave hindcasting. However, with the development of high speed processors, several sophisticated numerical models have been developed for wave prediction. These models are mostly phase-averaged spectral wave models developed in three generations. In the last two decades, third generation wave models have been used widely in academic and practical projects. In this regard, Port and Maritime Organization has produced his own model, PMO Dynamic. This model has been developed as a part of first three phases of Monitoring and Modeling of Study of Iranian Coasts project. PMO Dynamic package is a software available for engineering purposes. It has several modules that have been developed for different objectives. Wave model is the module which is used for the generation and transformation of wind waves in coastal areas. In this paper, in order to test the PMO Dynamic model capabilities, it has been applied for the prediction of wave parameters in Bushehr Bay and the results have been compared with MIKE21 SW model and measured data.

The effectiveness of tuned mass friction damper (TMFD) in suppressing the Dynamic Response of the structure is investigated. The TMFD is a damper which consists of a tuned mass damper (TMD) with linear stiffness and pure friction damper and exhibits non-linear behavior. The Response of the single-degree-of-freedom (SDOF) structure with TMFD is investigated under harmonic and seismic ground excitations. The governing equations of motion of the system are derived. The Response of the system is obtained by solving the equations of motion, numerically using the state-space method. A parametric study is also conducted to investigate the effects of important parameters such as mass ratio, tuning frequency ratio and slip force on the performance of TMFD. The Response of system with TMFD is compared with the Response of the system without TMFD. It was found that at a given level of excitation, an optimum value of mass ratio, tuning frequency ratio and damper slip force exist at which the peak displacement of primary structure attains its minimum value. It is also observed that, if the slip force of the damper is appropriately selected, the TMFD can be a more effective and potential device to control undesirable Response of the system.

The directional Response and roll stability characteristics of a partly filled tractor semi-trailer vehicle, with cylindricaltank, are investigated in various maneuvers. The Dynamic interaction of liquid cargo with the tractor semi-trailervehicle is also evaluated by integrating a Dynamic slosh model of the partly filled tank with five-degrees-of-freedom ofa tractor semi-trailer tank model. The Dynamic fluid slosh within the tank is modeled using three-dimensional Navier-Stokes equations, coupled with volume-of-fluid equations and analysed using the FLUENT software. The coupledtank-vehicle model is subsequently analysed to determine the roll stability characteristics for different maneuvers. Theresults showed the interaction of fluid slosh with vehicle's Dynamic. Another findings of this investigation also revealed that the roll stability of a tractor semi-trailer tank carrying liquid was highly affected by fluid sloshing and caused degradation of roll stability in comparison with vehicle carrying rigid cargo.

In this paper, the Dynamic Response of an axially moving viscoelastic beam with simple supports is calculated analytically based on Timoshenko theory. The beam material property is separated to shear and bulk effects. It is assumed that the beam is incompressible in bulk and viscoelastic in shear, which obeys the standard linear model with the material time derivative. The axial speed is characterized by a simple harmonic variation about a constant mean speed. The method of multiple scales with the solvability condition is applied to dimensionless form of governing equations in modal analysis and principal parametric resonance. By a parametric study, the effects of velocity, geometry and viscoelastic parameters are investigated on the Response.