Sharif Digital Repository

According to current trend of energy production and consumption in the world, economic problems in various countries and too many eco-system disorders in which created by an unsustainable trend in development, recently, the concept of “sustainability” and in the following “sustainable development” has been featured by scientists, researchers and policy makers in different scientific disciplines specially energy system engineering. Therefore exact recognition of unsustainability of local and global energy supply and demand system is very essential. In this research after selection of five energy indicators for sustainable development by Delphi and MCDM methods, future perspective of Iranian... 

In this thesis we study the exponential stabilization of the one dimensional compressible Navier-Stokes system, in a bounded interval locally around a constant steady state by a localized distributed control acting only in the velocity equation. In fact this is an analysis of a paper that published by Shirshendu Chowdhury, Debayan Maity, Mithily Ramaswamy and Jean-Pierre Raymond in Journal of Differential Equations. We determine a linear feedback law able to stabilize a nonlinear transformed system. Coming back to the original nonlinear system, we obtain a nonlinear feedback law able to stabilize locally this nonlinear system. The result is providing feedback control laws stabilizing... 

The application of Stochastic Differential Equations in branches like nonlinear control,robatic systems, financial mathematics and etc. has grown impressively nowadays. In this thesis, we are going to introduce this equations and study their stability. First, we will present methods to check the stability of nonlinear systems dx(t) = f(x(t); t)dt using Lyapunov’s theorem.Then we will study stability of autonomous systems using it’s results. In the case of instability, we will study the possibility of stabilizing the stochastic equations dx(t) = Ax(t)dt + Σn i=1 Bix(t)dWi(t) by using Brownian motions and these methods. In the end, we will study the stabilizablity conditions of instable... 

In this study, Euler-Bernoulli and Timoshenko beams with delayed boundary control are investigated. Deriving governing dynamic feedback control equations, exponential stability of these beams are obtained under more generalized conditions. For this purpose, time delay of system is omitted using tools in control engineering; then, an appropriate control approachis is found for this modified system.In the next step,closed loop system is extracted, which demonstrate that system is stable exponentially. This stability which is acquired for closed loop systems is also valid for primary system