Sharif Digital Repository

The extraordinary ability of the human brain to solve various problems has led scientists to simulate models of the human brain. One of these simulated models is artificial neural networks. Today, the power of artificial neural networks is not overlooked. The ability of artificial neural networks to solve various types of issues led us to use the thesis to solve some of the graph-based problems. Quite accurately, this graph-based problem is a matter of identifying the source of rumor in a network. In many graph networks, whether natural networks such as the network of neurons in the human brain or synthetic ones such as the types of social networks, it is possible that a rumor spreads across... 

Emphasis on the expansion of education in Iran's development strategy and increasing demand for higher education in the 2000s required the country to develop higher educational institutes. Unprecedented growth of these institutes in the second half of 2000s was so vast that in 2008 all the counties in Iran had at least one institute. These institutes were established even in the smallest counties in order to solve the problem of transportation for its settlers, and on the other hand, developing higher education institutes in larger cities resulted in an increase in the acceptance rate of these institutes and their accessibility for the people. Moreover, lower accessibility to higher... 

The successful development and implementation of a knowledge management system requires principles and instructions compatible with the organization. In the absence of essential and domestic components of a given organization, the process of knowledge management implementation will fail to be successfully completed. There are now various models for the implementation of knowledge management; however, these models only recommend general strategic guidelines, hardly offering any specific strategic plans as to how organizations can successfully and effectively implement knowledge management. Since the promotion of productivity is the ultimate goal of knowledge management, the present research... 

The everyday increasing electricity consumption of household and industrial sectors across the world, and also the limited generation capacity and fuel supplies has led electricity companies, whether in private or government sectors, to focus deliberately on power generation planning, its costs, risks and constraints Because of many reasons including high efficiency, low cost of capital investment, expeditious permitting, and operation flexibility of gas-fired generating units, electricity companies prefer them to old ones like coal-fired or oil-fired generating units. Thus natural gas has gained a significant share in the portfolio of electricity generation fuel resources, and it is... 

An a priori analysis is performed to assess the performances of Laminar Flamelet Decomposition (LFD) and Conditional Source-term Estimation (CSE) methods in predicting conditional and unconditional filtered production rates and mass fractions for turbulent premixed flames over a wide range of Karlovitz numbers, which is an indicator for the level of turbulence-chemistry interaction in premixed combustion.In LFD, it is assumed that a turbulent flame is composed of strained laminar flamelets. By presuming the functional form of the probability density function (PDF) of the progress variable and inverting the integral equation for the unconditional filtered mass fractions of one of the species,... 

In the past decades, hydrogels have been used as an adsorbent with high potential to remove pollutants in water. Hydrogels are three-dimensional polymer networks that have the ability to absorb and store water and water-soluble compounds due to the presence of hydrophilic functional groups in their structure. Different particles with unique characteristics can be used to increase the efficiency of hydrogel absorption. Based on the type of pollutant, hydrogels are divided into three different forms, including particles, films and nanocomposites. In this research, the absorption effect of metal cations as well as the absorption kinetics of polyvinyl pyrrolidine-based hydrogels, sodium... 

In this research project, the aim was to investigate the potential of olive leaf extract as an eco-friendly inhibitor for enhancing the corrosion resistance of reinforcing steel in simulated geopolymer concrete pore solution (GCP) containing chloride ions. The inhibitory effects of olive leaf extract were evaluated using various electrochemical techniques as well as scanning electron microscopy. The main phenolic compounds present in olive leaf extract were identified using high performance liquid chromatography (HPLC). Moreover, the elements and chemical bonds present in the surface passive film of the steel bar immersed in the olive leaf inhibiting system were characterized using... 

In this project, modeling, simulation, and control of the Saccharomyces Cerevisiae were studied. In the first section, simulation and control of a structural model of saccharomyces Cerevisiae were performed. Fuzzy Logic Controller (FLC) as a model-independent controller and Global Linearization Controller (GLC) as a model-based controller were designed. Additionally, two types of Kalman filters were designed to predict all states of the structural model: 1-Extended Kalman Filter (EKF), 2- Unscented Kalman Filter (UKF). As a concise explanation, the control action of the GLC is a function of all states of the model, and since that measuring all metabolites is not practical, the EKF and UKF...