Sharif Digital Repository

Investors are looking for profit making oppurtunities and using them to maximize their wealth. For investing in stock exchange, investors should be able to valuate the stock price rationally, so that he/she can define which stocks are trading below their intrinsic value. Stock price is the discount of future dividends of stock, but for discounting accurate rate is needed. Main goal of this study is presenting a way to calculate the proper discount rate or expected rate of return for investors. Method which has been studied in this thesis is “Fama & French five factor asset pricing model” which has been publish 2015 (Fama & French, 2015). The model concentrates on five factors to describe the... 

This thesis is a part of national studies of “attractiveness analysis and strategy formulation of fuel cell technology in Iran" that was done during more than two years with the guidance of fuel cell steering committee. In this thesis, first of all the possibility of applying the technology strategy model of Arnold Hax in national level was investigated. For this purpose, with regard to the fuel cell technology specifications and status in the country, from the perspectives of national need to the technology, capabilities of technology in the country and new applications of technology, the technology strategy models of positioning school were studied and from the models of this approach,... 

Mass-action chemical reaction systems are frequently used in computational biology. The corresponding polynomial dynamical systems are often large (consisting of tens or even hundreds of ordinary differential equations) and poorly parameterized (due to noisy measurement data and a small number of data points and repetitions). Therefore, it is often difficult to establish the existence of (positive) steady states or to determine whether more complicated phenomena such as multi-stationarity exist. If, however, the steady state ideal of the system is a binomial ideal, then we show that these questions can be answered easily. The focus of this work is on systems with this property, and we say... 

Due to the expansion and development of traffic routes, expecting customers to stay at a place for a long time would rise dissatisfaction and so on in this present study we are going to consider classical vehicle routing problem with simultaneous pick-up and delivery. Vehicles are allowed to have multiple trips and to improve customer’s flexibility and improving service level, different potential locations for each customer are considered. This type of problems in the literature are called vehicle routing problem with roaming deliveries and we expand it with some strong assumption to make the problem more real.In the proposed model there is an objective function that minimizes both variable... 

Interaction of vortices with particles is one of the complex and fascinating phenomena in fluid dynamics, which is often observed in wind turbines operating in dusty environments. In these turbines, dynamic stall occurs where vortices continuously form and dissipate. In this study, the impact of the presence of dust particles on dynamic stall, which can noticeably affect the aerodynamic efficiency of wind turbines, has been examined and analyzed; We focus on three airfoil models of the horizontal-axis wind turbines. namely S809, S822, and SD7062 at a Reynolds number of 10^6. These were examined using numerical simulation, with k-ω SST turbulence model and discrete phase model (DPM). The... 

DIRECT reduction is a process for reducing iron ore in the solid state. The product is in the form of sponge iron. This can be used directly as a raw material for steelmaking in an electric arc furnace. MIDREX process produces more than 60 percent of global DRI production. Because of high potential natural gas and iron ore resources in Iran and also lack of scarp, MIDREX direct reduction process is feasible. The main function of the MIDREX shaft furnace is to generate sponge iron from iron ore. The solids flow downwards by gravity and the reducing gases flow upwards in counter current, while the corresponding chemical transformations occur. Physical phenomena in the reactor could be... 

Many efforts have been put into increasing the efficiency of dye-sensitized solar cells that part of it has been devoted to structure and chemical composition of photoanode electrode. In this thesis, the effect of changes in the composition and its influence on light scattering ability in photoanode of dye sensitized solar cells was studied.First, the nanoparticles of titanium dioxide powder through solvothermal method as well as spherical particle and barium titanate powder by sol-gel method were synthesized. XRD and FE-SEM analyses indicated that synthesized powders are in good size and morphology regarding the intended chemical composition. Optical properties of TiO2 particles were... 

Enzymes are an important part of detergents, they reduce the activation energy of the reaction and thus increase the efficiency of the process. Protease enzyme is one of the most common enzymes in detergents. Bacillus strain is the most important strain in the production of this enzyme and among the species of Bacillus, Bacillus subtilis is the most used. Bacillus subtilis is a gram-positive, rod-shaped bacterium. This bacterium is considered a non-pathogenic cell that has the ability to form spores and prevent death and damage in harsh conditions. In this study, CRISPR system was used to modify the genome of Bacillus subtilis ATCC 6633 in order to increase alkaline protease. To increase the... 

Genetic engineering of cells has been one of the most effective ways to increase protein production in wild strains. Among the various genetic engineering techniques, the CRISPR/Cas9 system that directly edits the cell chromosome, yielding greater efficiency and easier operation. In this study, we used this system to modify the genome of Bacillus subtilis ATCC 6633 to increase the production of extracellular alkaline protease enzyme. Alkaline protease enzyme has many applications in different industries, but in this study, the application of this enzyme in the detergent industry has been considered. To increase the production of this enzyme, we disrupted and prevented the gene responsible... 

Recent success of Deep Learning models, resulted in their evergrowing application in many fields. However these models usually require huge datasets, which can sometimes be hard to collect. One of the challenges related to medical data, is the Batch Effect; Medical data is usually gathered through multiple experiments. Each experiment might have a slightly different conditions than the other, resulting a shift in the data related to that batch. Batch effects can have more severe impact during testing time, as the shift in the data distribution could be bigger. Many methods have been proposed to reduce or remove the effect of external conditions on data distribution.Deep Learning models have... 

Industrial enzymes can generally be classified into three groups: carbohydrases, proteases and lipases, which account for a major part of the global enzyme trade. Proteases, in particular, have always been extensively studied and investigated due to their widespread use in various industries, such as food, pharmaceutical, chemical, and agricultural sectors. Proteases are a group of proteolytic enzymes that break down proteins and peptides into their constituent amino acids by hydrolyzing peptide bonds. Among the family of proteases, alkaline serine proteases have special biocatalytic abilities in both aqueous and organic environments. Their suitable resistance in alkaline environments and... 

Solvatochromic parameters (ETN: normalized polarity parameter, π*: dipolarity/polarizability, β: hydrogen-bond acceptor basicity, α: hydrogen-bond donor acidity) have been determined for binary mixtures of propan-2-ol, propan-1-ol, ethanol, methanol and water with recently synthesized ionic liquid (2-hydroxyethylammonium formate) at 25 ◦C. The applicability of nearly ideal combined binary solvent/Redlich-Kister equation was proved for the correlation of various solvatochromic parameters with solvent composition. Solute-solvent and solvent-solvent interactions were applied to interpret the results. Heterogeneous catalytic hydrogenation of cyclohexene, catalyzed by Pt/Al2O3, was carried out in... 

High-quality online services demand reliable and fast packet delivery at the network layer. However, clear evidence documents the existence of compromised routers in the ISP and enterprise networks, threatening network availability and reliability. A compromised router can stealthily drop, modify, inject, or delay packets in the forwarding path to launch Denial-of-Service, surveillance, man-in-the-middle attacks, etc. So researches tried to create intrusion detection methods to identify adversarial routers and switches. To this end, data-plane fault localization (FL) aims to identify faulty links and is an effective means of achieving high network availability. FL protocols use... 

Confining nematic liquid crystal between two curved boundary conditions while the nematic molecules have a degenerate planar anchoring leads to complex and beautiful textures of molecular disparagement(defect) in the bulk and on the surfaces. Such the liquid crystal shells are made with double-emulsion techniques in microfluidic devices have provided applications for micro-scale colloidal linkers.In this work, we have numerically minimized the elastic energy in one-constant approximation in present of Fournier’s degenerate surface potential with finite element method. The nematic shell is confined between two spherical surfaces that we have studied the final energies and their related... 

In this study the behavior of steel bracings under cyclic loading, is modeled with finite element method. Analysis have shown that after local buckling in plastic mid-span position, due to the severe geometry change, the strain grows rapidly, The sharp growth of plastic strains is entitled as strain rises. Geometry change created will cause the collapse brace speeding up. In fact, the main local buckling can be used as a determinative factor in performance base design for steel braces. So the thesis has been investigated, using the parameters fracture life to quantify local buckling and fracture. Also with using the CVGM model, the fracture of the brace could be predicted. The analytical...