Sharif Digital Repository

One of the most important parts of bacteria growth is specific concentration of nutrients added. Although the trace amount of heavy metals are required for bacteria growth, after a threshold concentration they may cause damage or kill the bacteria. Scientifically speaking, all these trace nutrients should be consider as a profitable source of energy for bacteria growth. There are several studies throughout pondering whether the advantages of using heavy metals, such as Zn, outweigh the drawbacks. It has been proven that heavy metals, especially, zinc salt, can improve microbial growth up to a specific threshold concentration. In this study, two upward submerged aerated reactors, which had 12... 

As the Internet traffic grows, the energy efficiency gains more attention as a design factor for the planning and operation of telecommunication networks. Therefore, researchers begin to devise solutions for energy conservation in many scientific disciplines. In this thesis, we focus on the study of energy efficiency in optical transport networks, specially, the newly proposed Spectrum sLICed Elastic optical path (SLICE) networks architecture. First of all, we will introduce energy consuming elements in SLICE networks and their power consumption model. Next, we present a dynamic energy efficient routing and spectrum assignment algorithm (EE-RSA) with regenerator placement (RP) capability for... 

Smart heat-sensitive polymers play a unique role in drug delivery systems due to reversible behavior in response to environmental changes, especially temperature changes. Among the heat-sensitive polymers, UCST polymers due to their specific behavior and very little-known polymers with this feature are the subject of many new researches. In the present study, New designed temperature-sensitive polymers with UCST capability based on acrylamide and vinyl acetate were synthesized. These copolymers were synthesized in different percentages of acrylamide by free radical polymerization in solution conditions. All polymers compounds were characterized by H-NMR, FT-IR, DSC and GPC measurements. The... 

Optimizing and reducing energy consumption will be a feature of smart cities in the future. In addition to the technical aspects of a technology, one of the most important obstacles to its lack of development is not considering economic factors. Investigating the economics and calculating the cost of using IoT systems in the energy sectors of a smart city is one of the most important issues. Using existing systems in buildings or adding limited and inexpensive hardware to make a building smart can make smartening a cost-effective operation and more widespread. In this research, a proposed architecture based on edge processing is described. In addition to receiving and displaying camera... 

There are several methods for measuring thin film thickness, however, for the analysis of liquid film motors [1] we need a method which is capable of measuring the thickness using a single image of the film. In this work, we use the colors that appear on thin films, such as soup bubbles, which is a result of light interference to calculate the thickness of the layer  

By direct and alternating electric field applied to thin film of liquid suspended in the air we can spin out and control it. Rotation pattern depends on the geometry of the electrodes and the applied magnetic field. This is called a rotating liquid film (Liquid Film Motor). To determine the cause of rotation, different models have been proposed. In this project we have tried to check the accuracy of any of the models. Using particle velocimetry using the photo, we calculate the velocity pattern. Then, using the Navier-Stokes equation calculate the acceleration and viscosity from the velocity. Then, for a special arrangement using a finite diffrent method, electric potential and the electric... 

Ultrasound waves have attracted substantial attention due to their potential for trapping the small particles, which cannot be handled by usual tweezers. The acoustic tweezer is a technology that is able to tarp and control the movement of micrometer to millimeter objects by standing or focused sound waves. Acoustic tweezers are the subject of many researches around the world, due to simplicity, cost-effective, biocompatibility and most important better performance in non-transparent optical environments, compared with optical tweezers.In this project, by using a ring piezoelectric and a power amplifier, an acoustic tweezer was designed and constructed. Moreover, the polystyrene particles... 

Thermal relaxation time is the time when maximum temperature of a particle get to 1/e of it’s initial value. The destruction of a tissue depends to this important parameter. This parameter has studied by Monte Carlo simulation of pulsed laser in to environment as healthy and cancerous tissue. The main goal of this method is providing proper temperature in a special area so that minimize thermal destruction around that area. In this thesis, temperature distribution of tissue that is caused by pulsed laser, has solved by new method;in this new method the pulse duration uses for Monte Carlo simulation. Also using the solution of radiation transfer equation by Discretes Ordinate Method, new... 

Climate change impacts especially on temperature and precipitation, may have various effects on agriculture and water demand of agriculture sector in different regions around the world. Based on numerous researches, these effects may be positive in a region while another region might endure negative effects. Therefore carrying out researches and developing methods to predict these impacts as well as mitigating strategies seem to be essential. The most worldwide accepted method is using global circulation models (GCMs) outputs under different greenhouse gases emission scenarios, and according to Intergovernmental Panel on Climate Change (IPCC) assessments. IPCC claims that the most recent... 

The citizens’ dissatisfaction with the decreased life and residential care quality is increasing as a result of the rapid growth and development of cities. To find an effective solution to reduce and control these harmful effects is one of the main concerns of urban managers and planners in most countries. In this research, various ecological and sustainability criteria were selected through library-based studies and relative recognition of the region. The Maps were mostly provided through satellite imagery and some by using synoptic data collected from the official aerology website of the country, Iran. Through surveying the experts, different criteria were evaluated and based on the... 

The purpose of this work is to introduce an inverse finite element tool for prediction of the blank geometry and forming severity in stamping of 3D sheet metal parts. To achieve this goal total deformation theory of plasticity has been employed. In this method the final 3D part is unfolded on the flat surface and therefore the problem is reduced to two dimensional computations. Some tooling effects including blank holder force, bending and unbending and effect of draw bead are also considered. To investigate the capability of this work, predictions of the blank shape and strain distribution and forming severity have been performed on two circular and square parts. The results have been... 

Cold roll forming is a process for manufacturing of long sheet metal products with constant cross sections. The base of this process is bending and formation of plastic deformation in sheet. In this process, bending operation occurs in several forming stations. The purpose of this project is estimation of the distance between stations in roll forming. This work is based on determination of deformation length. In this study, first, the researches done in the roll forming is expressed. Then, a relation for estimation of deformation length has been derived that could be used in different stages of roll forming. Compared with other works, the work hardening effect has been considered in the... 

It is our purpose in this study to compare and analyze behavioral aspects of residential property valuation in Iran. More specifically, this research aims to explore the attributes that influence the value of residential property from the consumers’ and valuers’ perspective to determine whether valuers account for consumer behavior accurately. Finally, we investigate which variables operate at the lower end of the market, as distinct from those influencing the value of higher priced property. The core methodology underpinning the measurement of buyer and valuer behavior is the use of survey analysis. The identification of variables employing a two stage process forms an initial but critical...