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yaghmaee--soheyla
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Investigation of Surfactin Behavior at the Presence of Wate, Oil, and Asphaltene
, M.Sc. Thesis Sharif University of Technology ; Roosta Azad, Reza (Supervisor) ; Yaghmaee, Soheyla (Supervisor)
Abstract
In this research, the behavior of surfactin at the presence of water, decane, and asphaltene is investigated. Decane is chosen instead of crude oil to simplify the model. In the first chapter, basic molecular structures are introduced. Furthermore, in the second chapter molecular dynamics simulation, as the main tool in these simulations, is introduced. In the third chapter, one of the most important quantities in chemical engineering, diffusion coefficient, is chosen to investigate the efficiency and accuracy of molecular dynamics simulation method to calculate such a quantity and results show that molecular dynamics simulation can present accurate quantities, more accurate than common...
Estimating watermarking capacity in gray scale images based on image complexity
, Article Eurasip Journal on Advances in Signal Processing ; Volume 2010 , December , 2010 ; 16876172 (ISSN) ; Jamzad, M ; Sharif University of Technology
2010
Abstract
Capacity is one of the most important parameters in image watermarking. Different works have been done on this subject with different assumptions on image and communication channel. However, there is not a global agreement to estimate watermarking capacity. In this paper, we suggest a method to find the capacity of images based on their complexities. We propose a new method to estimate image complexity based on the concept of Region Of Interest (ROI). Our experiments on 2000 images showed that the proposed measure has the best adoption with watermarking capacity in comparison with other complexity measures. In addition, we propose a new method to calculate capacity using proposed image...
Modeling and Simulation of Alcoholic Fermentation of Sugarcane Blackstrap Molasses
, M.Sc. Thesis Sharif University of Technology ; Yaghmaee, Sohila (Supervisor)
Abstract
Fed-batch fermentation is a valuable and cost-effective method for bio-based production of various products such as ethanol, which has various applications in various industries.In recent years, bioethanol production has been given special attention in many countries. For this reason, the mathematical modeling of production of these products is very important for their optimal and cost-effective production. Given the transient and dynamic nature of fermentation and its specific complexity, mathematical modeling of fed-batch bioreactors is difficult and complicated. In this research, an unstructured model was used to predict the production of ethanol from blackstrap sugar cane molasses based...
Achieving higher perceptual quality and robustness in watermarking using Julian set patterns
, Article IEE Proceedings: Information Security ; Volume 153, Issue 4 , 2006 , Pages 167-172 ; 17470722 (ISSN) ; Jamzad, M ; Sharif University of Technology
2006
Abstract
Some of the most important classes of watermark detection methods in image watermarking are correlation-based algorithms. In these methods usually a pseudorandom noise pattern is embedded in the host image. The receiver can regenerate this pattern by having a key that is the seed of a random number generator. After that if the correlation between this pattern and the image that is assumed to have the watermark is higher than a predefined threshold, it means that the watermark exists and vice versa. Here, we show the advantage of using the Julian set patterns as a watermark, instead of the commonly used pseudorandom noise pattern. Julian set patterns can be regenerated in receiver with few...
Introducing a new method for estimation image complexity according to calculate watermark capacity
, Article 2008 4th International Conference on Intelligent Information Hiding and Multiedia Signal Processing, IIH-MSP 2008, Harbin, 15 August 2008 through 17 August 2008 ; 2008 , Pages 981-984 ; 9780769532783 (ISBN) ; Jamzad, M ; Sharif University of Technology
2008
Abstract
One of the most important parameters in evaluating a watermarking algorithm is its capacity. In fact, capacity has a paradoxical relation with other two important parameters: image quality and robustness. Some works have been done on watermarking capacity and a few on image complexities. Most works on watermarking capacity is based on information theory and the capacity values which are calculated based on these methods are very tolerate. In this paper we propose a new method for calculating image complexity based on Region Of Interest (ROI) concept. After that we analyze three complexity measures named: Image compositional complexity (ICC), Quad tree and ROI method, with three different...
Introducing a two dimensional measure for watermarking capacity in images
, Article Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 25 June 2008 through 27 June 2008, Povoa de Varzim ; Volume 5112 LNCS , 2008 , Pages 213-220 ; 03029743 (ISSN) ; 9783540698111 (ISBN) ; Jamzad, M ; Sharif University of Technology
2008
Abstract
One of the most important parameters in evaluating a watermarking algorithm is its capacity. Of course capacity has a paradoxical relation with two other important parameters: image quality and robustness. Generally, watermarking capacity is expressed by bit per pixel (bpp) unit measure. This measure does not show what the side effects would be on image quality and capacity. Therefore, we proposed a two dimensional measure named capacity curve which shows the effects of capacity on visual quality. In this measure we can find the amount of degradation by a numerical value for each modification in pixels. Our experimental results are compatible with previous works in this field. © 2008...
Using julian set patterns for higher robustness in correlation based watermarking methods
, Article 5th IEEE International Symposium on Signal Processing and Information Technology, Athens, 18 December 2005 through 21 December 2005 ; Volume 2005 , 2005 , Pages 358-362 ; Jamzad, M ; Sharif University of Technology
2005
Abstract
Some of the most important classes of watermark detection methods in image watermarking are correlation based algorithms. In these methods usually a pseudorandom pattern is embedded in host image. Receiver can regenerate this pattern by having a key that is the seed of a random number generator. After that if the correlation between this pattern and the image that is assumed to have the watermark is higher than a predefined threshold, this means that the watermark exists and vise versa. In this paper we showed the advantage of using the Julian set patterns as a watermark, instead of commonly used pseudorandom noisy pattern. Julian set patterns can be regenerate in receiver with few...
Computing watermark capacity in images according to their quad tree
, Article 5th IEEE International Symposium on Signal Processing and Information Technology, Athens, 18 December 2005 through 21 December 2005 ; Volume 2005 , 2005 , Pages 823-826 ; Jamzad, M ; Sharif University of Technology
2005
Abstract
Determining the capacity of watermark for images is a complex task. This capacity may be influenced by many factors such as the content of image and also the strength of watermark. In some recent works the image content has been considered for calculation of watermark capacity. One such approach is to use the Noise Visibility Function (NVF) introduced in [3]. In this paper we introduced a new method for finding NVF according to the quad tree representation of image instead of using pixel neighborhood data. Our experimental results showed that the depth of a pixel in image quad tree represents much information about the pixel and its maximum allowable distortion compared to pixel neighborhood...
Experimental Studies for Lactase Immobilization on the Polymer base and Characterising
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor)
Abstract
Immobilization of β-D-galactosidase represents an important approach for development of lactose hydrolysis technology.Chitosan proved to be an excellent carrier for β-Dgalactosidase immobilization, by both covalent binding and sol-gel entrapment combined with adsorption. Among different preparation methods of chitosan support particles for covalent binding, emulsion cross-linking was the most efficient, producing narrow-sized microspheres, without aggregation.The best process parameters of β-D-galactosidase immobilization by covalent coupling on chitosan microspheres were found as 3% glutaraldehyde cross-linker concentration, enzyme loading of 27 mg protein/g dry support, 6 h reaction time,...
Choosing a Suitable Microalgae for Bioremediation of Heavy Metals Regarding Iran's Clamate
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor)
Abstract
The pollution of water resources with heavy metals as a result of industrial activities threatens the lives of all living organisms. Therefore, separation of heavy metals from wastewater before entering our invironment is very important. Various chemical and physical methods such as absorption, chemical precipitation, extraction by solvent and ion exchange can be used to separate heavy metals but each of these methods have their own problems such as imperfect separation of heavy metals, need for expensive facilities and refining systems, high energy consumption and leaving pollutant residuals that need to be separated. On the other hand, the methods mentioned above can not separate heavy...
Green Synthesis of Metal-Organic Framework Based Biopolymer for the Removal of Dye and Pharmaceutical Pollutants in Water
, Ph.D. Dissertation Sharif University of Technology ; Yaghmaee, Soheila (Supervisor)
Abstract
In this research, in order to overcome the limitations of the current wastewater treatment technologies, two types of green biocomposite, biocompatible, with high removal capacity for emerging pollutants from wastewater have been synthesized. The general steps of doing the work in this treatise for each category of biocomposite include green synthesis, processing and optimization of the synthesis method, structural characterization of the synthesized compounds, checking their performance to remove the model pollutant, investigating the effect of operational parameters on the removal efficiency, determining kinetics, isotherm and mechanism. And at the end was the assessment of biocomposite...
Modeling and Simulation of Bioelectrochemical Systems
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor)
Abstract
The objective of the present research, for the first time, was to configure a novel dynamic model to be applied in a general manner to simulate bioelectrochemical systems including microbial fuel cell and microbial electrolysis cell. Biochemical reactions engaged in organic substances degradation in both anolyte and biofilm were described by two anaerobic digestion models; Bernard’s anaerobic digestion model and ADM1. In addition, the bioelectrogenesis and electron transfer were modeled based on the direct electron transfer mechanism across the conductive biofilm. The biofilm simulation was established upon the one-dimensional distributions of substrates and microorganisms. In this study,...
Experimental Investigation of Bio-hydrogen and Bio-electricity Production in an Annular Single-chamber Microbial Fuel-cell By Produced Waste Water Treatment
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor)
Abstract
This study works on the novel researchment about produced waste water treatment in an annular single-chamber microbial fuel cell.This configuration has a spiral anode which increase available surface for microorganismes.In this study two main goals are followed;first Bio-eletricity production in a microbial fuell cell and second Bio-hydrogen production in a microbial electrolysis cell. In bio-electricity production effect of two parameters were considered;effect of light and substrate concentration .Two systems were used in this research;one of them was exposed to the light and another was out of reach of any light.Results show that darkness has better effect on the cell’s performance...
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor) ; Maghsoudi, Vida (Supervisor)
Abstract
This practice investigates about the resistance & sustainability of a sample of available microorganisms in fruit juices vs. a natural anti microbe called vanillin. To be more precisely the anti bacterial characteristic of vanillin has been tested against famous pathogenic organism Escherichia Coli in apple juice. The practice has been experienced for different concentrations of Vanillin, controlling & reducing the microbe concentration in apple synthetic juice. The effect has been investigated by measuring sensitivity of results in two different temperatures one in 8 degree of centigrade & other in 15, in each temperature two PH have been tested (PH = 3.5 & 4.5) 0-40-80 m-molar as 3...
Application of Bioleaching Technology in Extraction of Metals from Spent Catalysts of Petroleum Refinery
, Ph.D. Dissertation Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor) ; Mousavi, Mohammad (Co-Advisor)
Abstract
In this project, bioleaching has been investigated as a solution for detoxification and metal recovery of spent hydrocracking catalysts of Tehran petroleum refinery which is listed as a hazardous waste. In this project four stages has been accomplished as follows: 1- Adaptation of Penicillium simplicissimum and Aspergillus niger with different heavy metals present in a spent hydrocracking catalyst, individually and with mixture of metals as well as adaptation by spent catalyst which the cumulative action of multi-metals enhanced the toxic effect; 2- The one-step, two-step, and spent medium bioleaching of the spent catalyst by the adapted fungi in batch cultures were investigated and...
Design and Construction of PCL Nanofiber Scaffold for Bladder Tissue Engineering
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor) ; Mashayekhan, Shohreh (Co-Advisor)
Abstract
In this project, a novel system of bioactive electrospun scaffold for bladder tissue engineering , has been investigated to control in vitro cell differentiation, and utilize in in vivo vascularization and tissue formation. This method doesn’t have custom bioactive scaffolds problems such as, protein instability, technical complexity and, difficulties in accurate kinetics prediction. First of all, protein loaded chitosan nanoparticles based on ionic gelation interaction between chitosan and Sodium tripolyphosphate were prepared. Maximum protein loading efficiency (80% for BSA & 99% for TGF-beta1) in chitosan nanoparticles was obtained at mean diameter of 51nm. Moreover polycaprolactone...
Computational Fluid Dynamics Simulation of Metals Bio Recovery in a Bubble Columm Bio Reactor
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor) ; Moosavi, Mahmud (Co-Advisor)
Abstract
Bubble column reactors owe their wide application area to a number of advantages they provide both in design and operation as compared to other reactors. This type of reactors can be used as bio reactors in which microorganisms are applied to perform a special process such as bioleaching. In this study, a laboratory scale bubble column reactor for bio recovery of metals in Tehran refinery used catalysts has been simulated via computational fluid dynamics (CFD). The results are presented in two parts; in first, hydrodynamic characteristics of multiphase flows in reactor are presented. Gas hold up, liquid phase velocity distribution and shear stress in bubble column for different aeration...
Hydrogel Design and Development for Osteoarthritis Treatment
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor) ; Mashayekhan, Shohreh (Supervisor)
Abstract
"osteoarthritis" is one of the most common joint diseases. This disease has a close relationship with factors such as aging, weight gain, genetics, mechanical pressures, and severe injuries. Although the mechanism of this disease is not fully understood, inflammation is one of the main causes of its exacerbation and progression. controlling inflammation can greatly help in controlling the disease. One of the common treatment methods for osteoarthritis is intra-articular injection of hyaluronic acid and triamcinolone as anti-inflammatory drug. Hyaluronic acid is the main component of synovial fluid, with its viscosupplementation property, prevents bones from rubbing against each other in the...
Study of Biological Extraction Kinetics of Heavy Metals from Spent Catalyst by Thermophilic Bacteria
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor) ; Mousavi, Mohammad (Supervisor)
Abstract
Every year, an enormous amount of catalysts are consumed in oil refineries during refining processes. After some regeneration cycles in order to recover their activity, they are not anymore effective and must be disposed. These spent catalysts are regarded as dangerous solid wastes as they significantly include some contaminations like vanadium, nickel, arsenic, sodium. From another point of view, the metals present in spent catalysts are highly valuable and are used extensively in steel industry and manufacture of special alloys. So, it sounds profitable to extract and recover these metals from such a cheap source instead of minerals and ores. Basically, there are two main processes, hydro-...
Biological Treatment of Drug Wastewater with Focus on Cyanide Compound
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor) ; Rustaazad, Reza (Supervisor)
Abstract
HCN is a highly valuable precursor to many chemical compounds ranging from polymers to pharmaceutical. Although cyanide can be destroyed and recovered by several processes, it is still widely discussed and examined due to its potential toxicity and environmental impact. The treatment methods for cyanide in common use today are physicochemical processes which have high operating costs and also produce chemical waste. Recently, biological processes have been studied because they are inexpensive and no effect to the environment. Therefore to achieve this object, Stimulation of indigenous microorganisms for waste degradation is a common technology. The process effluent from the gold extraction...