Sharif Digital Repository

Edwards-Wilkinson’s equation can be achieved from a Hamiltonian. When we have the Hamiltonian for the system, there are common approaches that makes it out of critical. In other words,the ”mass” should be added to the system. In this study we have tried to simulate and solve analytically these models that are involved mass term. We try to onstruct these mass terms in a way that have a minimum impact on the system and we study the quantities that characterize the out of critical behaviors  

Surface Growth processes, as critical phenomena, have long attracted physicists’ attention. In many cases, the surfaces exhibit scale-free properties and they become fractals. Based on the large scale dy- namics of each model, one can divide the different models into niversality classes. Two well-known universality classes are Edwards-Wilkinson and KPZ. the kind of noise present in the stochastic differ- ential equation describing the model, can determine the large-scale dynamics to a large extent. In this research, we have perturbed the Edwards-Wilkinson dynamics to make it suitable for describing growth processes in non-homogeneous environments, such that the noise gets stronger in higher... 

Phase change and deposition of solid particles in liquid flows are undesirable in industrial and natural processes and hazardous in some cases. Considering the intentions to petroleum exploration in deep waters such as Caspian Sea, the Gulf of Mexico and North Sea, precipitation and deposition of wax crystals in petroleum and gas pipelines is a real concern due to the fact that during production, oil is exposed to more intense temperature gradient (the dominant mechanism in wax deposition) and its heavier components change their phase to solid and deposit. Wax deposition in production lines starting at crude oil storage tanks is not accepted due to reduction in production rate and... 

Surface growth is one of subjects that has many applications in industry, and its deep recognition in physics remarkably helps us in understanding of critical systems. There are various approaches for analyzing this phenomenon, one of the most important of which is differential equations.In this approach, with respect to surface properties, a partial differential equation is introduced, and the critical exponents are obtained by solving it. In this thesis, after studying several continuum equations such as: Edwards-Wilkinson, KPZ, and Wolf-Villain equation,we provide numerical solutions of these equations in presence of height dependent noise. The role of noise in stochastic differential... 

Blood glucose regulation in type 1 diabetes patients requires the delivery of the proper amount of insulin from an external source. The literature of Blood Glucose Control signifies the superiority of model-based controllers over the other ones. Regarding its lack of need to complicated on-line calculations and the simplicity of its implementation on a micro-chip, the explicit Model Predictive Controller is preferred over the implicit MPC. Currently proposed explicit MPC controllers have employed relatively simple models representing human glucose-insulin dynamics. In this thesis, an explicit MPC controller is designed using mp-QP based on Sorensen’s 19-state comprehensive model which has... 

One of the common and efficient methods in the construction of large-scale structures from composites is the Vacuum Assisted Resin Transfer Molding (VARTM) method, which is widely used in the automotive industry, wind turbine blades, warships and pleasure boats, etc. VARTM is one of the liquid molding methods in which one side of the closed mold is replaced with a vacuum bag and the resin flows into the mold only with the help of air pressure (pressure of one atmosphere). One of the main challenges in the vacuum resin molding process is to be aware of the physics governing the flow motion in the porous mold so that the dry spots formed in the mold can be located accordingly. On the other...