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Evaluating the Energy Consumption of Fault-Tolerance Mechanisms In Processors Implemented on Sram-Based Fpgas
, M.Sc. Thesis Sharif University of Technology ; Ejlali, Alireza (Supervisor)
Abstract
With growing interest in the use of SRAM-based FPGAs in space and other radiation environments, there is a greater need for efficient and effective fault-tolerant design techniques specific to FPGAs. The soft errors vulnerability of SRAM-based FPGAs limits their usage in safety-critical applications. Moreover, the rate of multiple soft errors increases due to the feature size reduction. Hence, this issue becomes a challenge against reliability of the implemented circuit on SRAM-based FPGAs. Appealing to specifics such as low cost and re-configurability in SRAM based FPGAs provide this ability to change implemented design remotely. This advantage is not negligible in safety critical...
, M.Sc. Thesis Sharif University of Technology ; Moshfegh, Alireza (Supervisor)
Abstract
ZnO is a wide and direct band gap (3.37 eV) semiconducting material with a large exciton binding energy (60 meV). It has been extensively studied in the last few years owing to its potential applications in various fields such as surface acoustic wave devices (SAW), transparent electrode, solar cell windows, photovoltaic devices, gas sensors and photoelectrochemical cells. Recently, much attention has been paid to rare-earth (RE) doped ZnO for possible applications in visible emitting phosphors in displays, high power lasers, and other optoelectronic devices. In this thesis, initially ZnO thin films were deposited on glass and ITO substrates using sol-gel dip-coating method. Optical and...
Monitoring of Biodegradation of Oxalate in Microfluidic Bioelectrochemical Systems
, M.Sc. Thesis Sharif University of Technology ; Bastani, Daryoush (Supervisor) ; Yaghmaei, Soheila (Supervisor) ; Mardanpour, Mohammad Mehdi (Co-Supervisor)
Abstract
In present study, bioelectrochemical degradation of oxalate as a substance which its concentration in kidney leads to urolithiasis in a microfluidic microbial fuel cell (MFC) was investigated. In addition, to define a novel application for the microfluidic MFC, measurement and monitoring of oxalate concentration were studied. This application can introduce the system as an implantable medical device for medical usage of urolithiasis and hyperoxaluria diseases. In this work, by designing and fabrication of two MFCs including a large-scale and microfluidic one, and measuring the outlet concentration of oxalate in the large-scale system, the outlet concentration of oxalate at microfluidic MFC...
Synthesis and Investigation on Physical and Photoelectrochemical Properties of Visible Active TiO2/Graphene Based Nanocomposite Thin Films for Hydrogen Production
, Ph.D. Dissertation Sharif University of Technology ; Moshfegh, Alireza (Supervisor)
Abstract
World population growth, depletion of fossil fuels resources depletion and increased air pollution resulting from their consumption, human society has had to replace fossil fuels with renewable sources. In this context, the production of hydrogen using solar energy is feasible candidate to replace fossil fuels, which can be produced by water splitting in a photoelectrochemical (PEC) cell using an appropriate photocatalyst. This clean production method has been attended by many researchers in recent years. The most common photocatalyst for the conversion of sunlight to hydrogen by splitting water is Titanium dioxide (TiO2). But high energy gap and fast electron-hole recombination rate in TiO2...
An Investigation on Physical and Photochemical Properties of Sol-Gel Derived MWCNT-WO3 Nanocomposite thin Films
, M.Sc. Thesis Sharif University of Technology ; Moshfegh, Alireza (Supervisor)
Abstract
WO3 have good electrochromic, gas sensor, photocatalyst, phoelectrochemical (PEC) properties. due its properties, tungsten oxide have many application in technology and industry. In this thesis, pure WO3 thin film and MWCNT-WO3 nanocomposite thin films with different weight percent of MWCNT/WO3 utilize for energy domain, particular hydrogen production with phoelectrochemical reactions spiliting water. For this purpose, initially WO3 thin films were deposited on glass and ITO substrates using sol-gel dip-coating method. Optical and surface properties of the films dried at 100ºC and annealed at 400 ºC had been investigated. UV-Visible spectrophotometer, atomic force microscopy (AFM), X-ray...
Simulation of Microcapsule Formation for Cell Encapsulation Application
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Saeed (Supervisor) ; Kazemzadeh Hanani, Siamak (Co-Advisor)
Abstract
Co-culture of different cells is necessary for cancer spheroid formation in preclinical drug tests. It is possible to produce thousands of micro-droplets containing different cells, i.e. microcapsules, in a short time, using droplet microfluidics. However the homogeneity of the cell numbers in the droplets has remained as an unsolved problem.Despite the large amount of experimental efforts to reduce the number of undesirable microcapsules, no one tried to utilize the ease of computer aided simulation for investigating different parameters. In this study, we develop a novel method for capturing cell encapsulation using CFD simulations. The effect of the cell suspension inhomogeneity and...
Particle Acceleration in Astrophysical Shock Waves and Laser-Induced Plasma Waves and its Simulation
, Ph.D. Dissertation Sharif University of Technology ; Anvari, Abbas (Supervisor) ; Samimi, Jalal (Supervisor)
Abstract
In this thesis, plasam kinetic aspects causing production of high-energy super-thermal particles in strongly nonlinear perturbations, including relativistic electron waves and shock waves occurred respectively in astrophysical and laser produced plasmas, have been studeied. Importance of kinetic simulations in this area has been demonstrated. In this respect, passing serious challenges, we have prepared a kinetic particle-in-cell (PIC) code and applied it within our supplied computational-resources. Relativistic electron waves produced via interaction of laser with tenouse plasmas have been deeply studied. These studies have resulted in new findings in fluid description of these waves,...
A Dependable Routing Architecture for Reconfigurable Devices
, M.Sc. Thesis Sharif University of Technology ; Asadi, Hossein (Supervisor)
Abstract
Reconfigurable devices are a popular platform for fast prototyping of digital system due to having high performance of hardware implementation along with flexibility of software. However, reconfigurable devices suffer from area, performance and dependability gaps in comparison with their Application Specific Integrated Circuit (ASIC) counterparts, which greatly limits their application.
The dependability gap originates from the sensitivty of configuration memory to soft errors. When a reconfigurable device configuration memory is affected by soft errors, their configuration will be invalid until reconfigured. Since the routing fabric is the origion of over 80% of soft errors in...
The dependability gap originates from the sensitivty of configuration memory to soft errors. When a reconfigurable device configuration memory is affected by soft errors, their configuration will be invalid until reconfigured. Since the routing fabric is the origion of over 80% of soft errors in...
The Fabrication of the Coupled Microfluidic Microbial Electrochemical Cells for Oxalate Biodegradation
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor) ; Mardanpour, Mohammad Mahdi (Co-Supervisor)
Abstract
This study invewstigates the performance of a coupled microfluidic microbial fuel cell-microbial electrolysis cell producing biohydrogen in presence of shewanella oneidensis MR-1 from excreted oxalate of human metabolic processes. The effect of different parameters such as cell geometry including spiral and straight microchannels, precipitation of nano-particles on anode surface, substrate flowrate and the number of microfluidic microbial fuel cell supporting required power for microbial electrolysis cell were assessed. By anode modification, the maximum current density of 428 W m-3 was obtained which is less than 6-fold of the maximum power density in the cell fabricated by zinc foil. The...
Design and Simulation of a Microfluidic Blood Cells Counting Device
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Saeed (Supervisor) ; Sani, Mehdi (Supervisor)
Abstract
A Lab-On-a-Chip (LOC) is a device which can integrate one or many laboratory functions on a small chip with millimeters to few square centimeters in size. LOC is a subset of MEMS devices and known as “Micro Total Analysis Systems” (µTAS) as well. LOC technology is closely related to microfluidics which primarily describes the physics, manipulation and study of minute amount of fluids.In this research we tried to simulate the performance of a microfluidic device for counting blood cells to find main factors of it for design and manufacturing. This research has two main sections, hydrodynamics of fluid inside the microchannels and finding electrical performance of designed Coulter counter for...
Investigation and Characterization of Circulating tumor Cells (CTCs) by the Microfluidics Systems
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Manoucher (Supervisor) ; Alemzadeh, Iran (Supervisor) ; Shamloo, Amir (Supervisor)
Abstract
Cancer is the second leading cause of death among humans as one of the major human concerns. More than 500,000 people die of cancer each year in the United States alone. Cancer mortality is mainly due to cancer metastasis. Metastasis is the escape of cancer cells from a primary tumor, the circulation of cells in the circulatory system (CTSs), the penetration of/from vessel wall, and the formation of a secondary tumor. It is still not clear how the cells survive in the circulatory system, along with the mechanical pressures and stresses that exist in the body's capillary channals. In this study, a microcirculation model for circulating cells with barriers was designed and constructed by the...
Circuit Model for Periodic Plasmonic Nanostructures Used as Light-rapping Back-structures in thin Film Solar Cells
, M.Sc. Thesis Sharif University of Technology ; Mehrany, Khashayar (Supervisor) ; Khavasi, Amin (Co-Advisor)
Abstract
In recent years, thin-film photovoltaic cells with thicknesses of less than 1-2 µm have been developed with potentially lower production costs. Due to the small thickness of the absorbing semiconductor in these cells, the absorption is inevitably low at energies close to the electronic band gap of the semiconductor. This is particularly a problem for thin-film devices. Recently، periodic metallic nanostructures supporting surface plasmons have been introduced as alternative solutions to achieve light trapping in thin-film solar cells.Full numerical methods are usually used for the analysis of these periodic structures. The main drawback of these methods is that they are time-consuming and...
Ions Acceleration in Laser-plasma Interaction
, M.Sc. Thesis Sharif University of Technology ; Sadighi Bonabi, Rasoul (Supervisor) ; Riazi, Zafar (Co-Advisor)
Abstract
Optimum conditions for the proton acceleration using radiation pressure acceleration in light sail regime is investigated using particle-in-cell simulations. Simulations results show that for a laser pulse with a dimensionless laser amplitude of a0 = 31 using circularly polarized laser pulse with sin2 shape at perpendicularly incidence are the best. Effect of two pulses with different duration and different amplitudes (a0 = 25; a′ 0 = 13) is also investigated in the condition of equal total energy of them to the single pulse and amplitudes of both of them are less than the single efficient laser pulse amplitude. Best delay time between two pulses was found by changing the delay time in...
SRAM Cell Design for Low Power Applications
, M.Sc. Thesis Sharif University of Technology ; Haj Sadeghi, Khosrow (Supervisor)
Abstract
From the cache of the personal computers to the main memory unit of SOCs, medical and wearable chips, Static Random Access Memory (SRAM) is widely utilizes. Preferable performance for SRAM varies with regard to the operating field. For instance, high speed access and performance is emphasized in the design of the cache for PCs. In contrast, power consumption and the area of the memory are the key design considerations for SOCs. Hence, the field in which SRAM is used, should be thoroughly studied. SOCs and medical chips suffer limitations in design due to using batteries as the source of energy and SRAMs consume a significant part of total power and occupy a large area on these chips. One of...
Experimental Study of Using Cellulosic Compounds in Tissue Engineering
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Manouchehr (Supervisor) ; Karimi, Afzal (Supervisor) ; Faghihi, Faezeh (Co-Supervisor)
Abstract
Fabrication and characterization of different surface charged cellulose electrospun scaffolds including cellulose acetate, cellulose, carboxymethyl cellulose and quaternary ammonium cationic cellulose for biomedical applications have been reported in this research. We describe preparation of cellulosic nanofibers through the electrospinning following deacetylation cellulose acetate. Moreover, surface modification of electrospun cellulose nanofibers is carried out to obtain carboxymethyl cellulose and quaternized cellulose nanofibers, respectively. At last, the structural, morphological, mechanical, swelling, wettability and the cell culture properties of the scaffolds were analyzed and...
Dynamic Simulation of Molten Carbonate Fuel Cell
, M.Sc. Thesis Sharif University of Technology ; Pishvaie, Mahmoud Reza (Supervisor)
Abstract
In this work, a model was presented for an MCFC fuel cell with internal reforming and combustion chamber. The model consists of mass and heat transfer equations beside the chemical and electrochemical reaction rate equations. Velocity distribution due to reactions and temperature distribution along the cell is considered. The model has been simulated in steady state form using finite difference method in MATLAB package environment accompanied by the analysis of the dynamic behavior of cell using method of lines in Simulink environment. Simulation results have been validated with experimental data extracted from literature. The last part of the work concerns with sensitivity analysis of some...
Development of Improved Conversion Energy System based on High Temperature Fuel Cells
, M.Sc. Thesis Sharif University of Technology ; Roshandel, Ramin (Supervisor)
Abstract
Sustainable development is the basic aim of energy researchers. But common conversion technologies with respect to efficiency, fuel type and pollution of them, need basic operating improvement to reach sustainable development. Aim of this project is investigation of high temperature fuel cells as basic energy convertor. To improve performance of fuel cell system, four integration systemsare modeled and proposed. Using integrated systems in combined cooling, heat and power is another way of improving performance of systems, that is done in this project.
To improve system performance, the optimum operating values of these parameters is determined. In order to use four proposed system in...
To improve system performance, the optimum operating values of these parameters is determined. In order to use four proposed system in...
Simulation of a Simple Model of Endothelial Cell Using Dissipative Particle Dynamics Method
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Saeed (Supervisor) ; Firoozabadi, Bahar (Co-Advisor)
Abstract
Endothelium is the interior layer of an artery made up of tremendous number of endothelial cells which are located side by side. Finding the effective parameters that cause the cells to obtain mechanical strength in different morphologies is a major effort in cell engineering studies. In this work a numerical model for endothelial cells is developed. This model has included cell's plasma membrane (the outer membrane of the cell), nucleus and cytoskeleton main components including intermediate and actin filaments as well as microtubules. The model has been validated by simulating the adhesion of the cells to a flat substrate and also atomic force microscopy (AFM) experiments. The two most...
Simulation, Design and fabrication of Kidney on a Chip
, Ph.D. Dissertation Sharif University of Technology ; Saeedi, Mohammad Saeed (Supervisor) ; Firoozabadi, Bahar (Supervisor) ; Mosadegh, Bobak ($item.subfieldsMap.e)
Abstract
Renal diseases and consequently kidney failure is one of the important death factors around the world in recent years. It causes hundreds of thousands die every year and is in progress. Researchers believe that increasing chemical and nonchemical materials density in the blood which is the air pollution, use of tobacco and other parameters cause renal cells misfunction in urine filtration and regulation of blood pressure. The goal of this work is design and fabrication of a microfluidic device which provides different cell types to be cultured and imposed pressure. To do this, a high throughput microfluidic device is needed to mimic kidney biologically. Having such a device helps to analyze...
Modeling and Simulating of Water Distribution in Different Layers of Direct Methanol Fuel Cell
, M.Sc. Thesis Sharif University of Technology ; Baghalha, Morteza (Supervisor)
Abstract
A two-dimensional, two-phase, nonisothermal model was developed in this work to investigate the water transport characteristic and water distribution in a direct methanol fuel cell (DMFC). Emphasis is placed on exploring the water distribution in different layers of DMF. The water and methanol crossover through the membrane were considered with the effect of diffusion, electro-osmotic drag, and convection. Governing equations including the prton and electron transport, continuity, momentum, species transport for methanol, water, and gases species, and the auxiliary equations are coupled to determine the output parameters. These parameters are the concentration distribution of the species,...