Sharif Digital Repository

The lateral force & its control has always been a great concern to structural designers. Based on the project’s location, this force can be either earthquake or wind force. In our country, Iran, the earthquake force is usually the dominant one. Of the most important differences between these two kinds of forces, we may point out the cyclic characteristics and nature of earthquake forces. One can choose different strategies to face the earthquake force including the use of dampers. Dampers exist in vast varieties of different categories which we will briefly explain in this thesis. Dampers can be used on their own or in combination with other lateral force resistance systems like bracings or... 

Nowadays, development of renewable electricity generation technologies, the advent of small efficient generators and increasing number of grid-connected consumers, have caused increasing interest in energy production next to the consumers locations. Distributed generation (DG) is often defined as small-scale generators that produce several kilowatts to tens of megawatts of electricity. One primary reason for using DG is its potential to reduce power losses in transmission and distribution networks. Several loss reduction methods such as capacitor placement, network reconfiguration and load management are used in distribution systems. Employing DG results in the highest loss reduction and... 

Chemotherapy is a proven and effective systematic approach to treat various types of cancers. Despite its advantages, chemotherapy would kill healthy as well as cancer cells. To overcome this problem, different controlling strategies are implemented. This study aims to provide a medicine drug delivery schedule for chemotherapy (by designing a proper controlling system) based on the verifiable mathematical models. First, the dynamic model is analysed and stability points are reviewed. The selected model has five state variables and two inputs. In this study, the focus is on dynamic model analysis and obtaining an effective and appropriate treatment pattern by designing a proper controller. To... 

Occurrence of natural disasters such as earthquake could seriously damage most buildings especially those with insufficient resistance located in urban worn-out textures. In order to reduce unpleasant consequences of an earthquake, appropriate policies need to be considered to persuade the beneficiaries to follow retrofitting standards in the process of planning, designing, and construction of buildings. These policies shall be implemented through institutions in arbitrary or obligatory forms, by encouragement or penalty mechanisms. In order to consider these policies, first of all we need to identify the beneficiaries and their particulars. By studying and considering subjects discussed in... 

Environmental issues and energy crisis have led the world attention to the renewable energies; especially wind power, since they have low cost and high reliability. One of the most challenging areas of studying for wind power is to increase the capacity of wind turbines. As a result, over the years, wind turbines have got progressively larger. Vibration is one of the problems that reduces the life and efficiency of wind turbines; and the growing size of the blades has worsen this problem due to the importance of nonlinear effects in large scale wind turbines. Researchers have been constantly working on this issue in order to make the wind turbines more efficient. In this research, a... 

Wind turbines have been the subject of many researches in recent decades. Optimization and continuous improvement of these systems play a decisive role in the development and exploitation of wind farms. Wind turbines can be studied from several aspects such as structure, dynamics, aerodynamics, electricity and control. In this research, robust power control of the wind turbine has been studied with emphasis on accurate 2 DOF mechanical and aerodynamic modeling. Aerodynamic coefficients of the turbine have been calculated using the numerical methods and the effect of this numerical modeling has been studied in comparison with the analytical methods on the turbine power control. Several new... 

In this research, the main purpose of the controller design is in the second region of operation of a wind turbine, which involves absorbing the maximum energy from the wind. WindPACT 1.5MW turbine has been investigated and the power coefficient of this turbine has been obtained using WT-PERF and FAST softwares. Simulations show that the results of both methods are well matched. Then, using ANFIS, a method for estimating the wind speed is derived from the data obtained by FAST. Inputs to the ANFIS system are the turbine aerodynamic power, rotor speed and blade pitch angle while the output of ANFIS system is the estimated wind speed. The maximum power coefficient of the wind turbine occurs... 

Best cancer treatment is the one which reduces the tumor density in minimum time and side effects, considering the input limitations. In this paper, tracking controller and robust controllers are designed to achieve the mentioned objectives, simultaneously. An ODE-based mathematical model of the human body under chemovirotherapy is selected, which includes the uninfected and infected tumor cells, free viruses, immune cells, and a chemotherapeutic drug. For tracking purposes, a servo controller based on the entire eigenstructure assignment (EESA) approach is applied to the model, continuously and discretely. For robust purposes H-infinity and D-K iteration approaches are implemented and... 

Laboratory studies to investigate the effects of different saline concentrations (such as sodium chloride or calcium chloride) on the soil water retention behavior of clayey soils and their volumetric changes have received much attention recently. However, many previous studies have investigated these effects in only one path of the SWRC (wetting or drying path) and the effects of saline concentration on hydraulic hysteresis have not been considered. In addition, researchers have frequently studied these effects on SWRC on clay samples, and little research has been done on collapsible soils. Therefore, the most important purpose of this study is to investigate the effects of increasing... 

Today, cancer mortality is one of the most important problems, even considering the scientific advances that offer more effective solutions to treat some diseases, providing a way to prevent and treat this disease is one of the most important issues that engineers have considered. This is achieved by designing a controller to minimize the size of the cancer tumor population, increase healthy cells, optimize treatment time, and drug dose.To achieve this goal, pharmacokinetic, pharmacodynamic, tumor growth, and healthy cell growth models, and mathematical models for subsystems that affect tumor growth, such as the angiogenic system, have been studied to develop a single mathematical model. In... 

This study proposes a probabilistic framework to quantify the seismic resilience of urban natural gas distribution networks. Infrastructure resilience is defined as the ability to maintain performance after a hazard or, in case of a loss of performance, return to the minimum desired level in the optimal time. The framework presented in this research is comprised of multiple interconnected probabilistic models. These models work in harmony to characterize the impact of the earthquake on various infrastructures such as the buildings and urban gas distribution network components, as well as the probable consequences of the earthquake. The post-earthquake recovery of the gas distribution network... 

Optimal use of available resources for construction projects depends on proper decision-making on how to spend resources. Optimization of resource consumption should be done taking into account project revenue. In this regard, investors need a suitable mechanism to predict the selling price of the construction project and the resulting profit. Therefore, investors and stakeholders need a suitable model with the help of which they can make decisions such as choosing materials to guarantee the desired profit from the sale. This research will provide a framework for constructing models for estimating the price of residential units by considering some features of the building and some economic...