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baghban-eslami-nejad--mohammad-reza
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Fabrication of Composite Scaffold Composed of Cartilage Extracellular Matrix/Chitosan with High Mechanical Strength for Cartilage Tissue Engineering
, M.Sc. Thesis Sharif University of Technology ; Mashayekhan, Shohreh (Supervisor) ; Baghban Eslami Nejad, Mohammad Reza (Supervisor)
Abstract
Methods that has been used for articular defects are faced with many limitations, so new therapies based on tissue engineering were taken into consideration in recent years. However, tissue engineering also encounters challenges regarding optimal scaffold construction and suitable cell source selection. Mature harvested chondrocytes are limited in number and may lose their chondrogenic potential in several cultures, leading to dedifferentiation. In addition, using stem cells also presents unique challenges associated with them, among which hypertrophic differentiation is the most substantial problem. Choosing the appropriate biomaterial similar to the cartilage structure with sufficient...
Topological Defects in Confined Nematics by Planar Anchoring
, M.Sc. Thesis Sharif University of Technology ; Ejtehadi, Mohammad Reza (Supervisor) ; Mozaffari, Mohammad Reza (Supervisor)
Abstract
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...
Optimal model of solid waste technology assessment
, Article 2005 ASME International Mechanical Engineering Congress and Exposition, IMECE 2005, Orlando, FL, 5 November 2005 through 11 November 2005 ; Volume 2005 , 2005 , Pages 69-76 ; 0791842185 (ISBN); 9780791842188 (ISBN) ; Saboohi, Y ; Sharif University of Technology
2005
Abstract
Review of waste management models indicate that optimization models based on the chain of waste flow are developed and applied in waste management systems. These models do represent the flow of material through few stages and they lack an integrated approach that may include the flow of material from the point of waste generation in different sectors till the end point at the land fill. It is also argued that the existing models do rarely consider the interrelated issues of economics, environment and social aspects. This conclusion has been followed by the development of an integrated multi stage and multi period dynamic model of waste flow based on quasi dynamic optimization techniques. The...
Elasticity of DNA Molecule The Role of Anisotropy, Asymmetry and Nonlocal Interactions
, Ph.D. Dissertation Sharif University of Technology ; Ejtehadi, Mohammad Reza (Supervisor)
Abstract
The DNA Molecule carries genetic information in almost all living organisms. The information coded on DNA is an instruction which organizes and conducts all living activities of the living organism. The role of DNA in biological processes is so fundamental that life, as we know, is not possible without DNA. Therefore, studying the biological properties of DNA is crucial for understanding the nature of life. In biological conditions, DNA molecule can be found in highly packed configurations. Since the DNA is a rather stiff molecule, the formation of these configurations cost a considerable amount of energy. The elasticity of DNA plays an important role here. The important question is: how...
Synthesis of Pt- Nanoparticle in Ionic Liquid Coated on Alumina and the Investigation of the Nature and Thickness of Ionic Liquid on Catalyst Pt / Al2O3
, M.Sc. Thesis Sharif University of Technology ; Gholami, Mohammad Reza (Supervisor)
Abstract
In this project ionic liquid and there mixtures were coated on Pt/ Al2O3 , the prepared catalyst were characterization by SEM, BET and XRD techniques.In the first stage the effect of the coated ionic liquid on the Pt/Al2O3 were investigated, on the rate of C=C hydrogenation. in the second stage effect of the thickness of ionic liquids on the rate of the cyclohexene hydrogenation were studied. Result revelad that by increasing the ionic liquid polarity, the reaction rate increased. Also the reaction rate decreased by increasing the thickness of ionic liquid
Development of Ratiometric Sensors Based on Fluorescent Nanostructures for Naked Eye Detection
, Ph.D. Dissertation Sharif University of Technology ; Hormozi-Nezhad, Mohammad Reza (Supervisor)
Abstract
In the first part of this research, we have developed a simple and effective ratiometric fluorescence sensor for selective detection of dopamine (DA) in alkaline media by simply mixing thioglycolic acid (TGA) functionalized orange fluorescent cadmium telluride (CdTe) quantum dots (QDs) with amino-functionalized blue fluorescent carbon nanodots (CDs). Under a single excitation wavelength of 365 nm, the sensor exhibits dual-emissions centered at 445 and 603 nm. The fluorescence of CdTe QDs is selectively quenched by DA, whereas the fluorescence of CDs is insensitive to the analyte. In the presence of different amounts of DA, the variations in the dual emission intensity ratios exhibit a...
Evaluation of refrigerant mixtures in three different cold-climate residential air-source heat pumps
, Article ASHRAE Transactions, 25 June 2016 through 29 June 2016 ; Volume 122 , 2016 , Pages 63-70 ; 00012505 (ISSN) ; 9781939200464 (ISBN) ; Aidoun, Z ; Eslami Nejad, P ; Sharif University of Technology
Amer. Soc. Heating, Ref. Air-Conditoning Eng. Inc
2016
Abstract
This paper addresses the challenge of improving the performance of heat pumps (HPs) in cold-climate conditions by applying refrigerant mixtures. The potential benefits of implementing R-32/CO2 zeotropic refrigerant mixtures in three different residential air-source HPs for cold climates are studied. The cases considered are conventional residential HP, HP with a variable mixture control system, and HP with a variable compressor speed. The seasonal performance of a heating system with these air-source HPs, supplemented with an auxiliary electric heater, is studied in the cold-climate city of Montreal, Canada. To this aim, a detailed screening HP model previously developed is modified and...
Technical assessment of ground-source, air-source, and hybrid heat pumps for single-family buildings in cold climates
, Article 25 June 2016 through 29 June 2016 ; Volume 122 , 2016 , Pages 270-280 ; 00012505 (ISSN) ; 9781939200464 (ISBN) ; Hakkaki Fard, A. M ; Aidoun, Z ; Ouzzane, M ; Sharif University of Technology
Amer. Soc. Heating, Ref. Air-Conditoning Eng. Inc
2016
Abstract
This paper discusses a technical comparison of a directexpansion ground-source heat pump (DX-GSHP) and an airsource heat pump (ASHP). To lower the ground heat exchanger size for cost reduction purposes, the system performance of a hybrid system is also evaluated using a supplementary air evaporator combined with the DX-GSHP. Detailed screening models previously developed for ASHPs and DX-GHSPs are first used to compare the seasonal performance of these two options for a residential building in the cold-climate city of Montreal, Canada. Then, the model is adopted for performance evaluation of the hybrid system. Additionally, different parameters including borehole total length and heat pump...
Extracting Cascaded Information Networks FromSocial Networks
,
M.Sc. Thesis
Sharif University of Technology
;
Rabiei, Hamid Reza
(Supervisor)
Abstract
The diffusion process propagates information, viruses, ideas, innovations and new be-haviours over social networks. Adopting a new behaviour, which is mentioned as an in-fection, starts from a little group of people. Spreading it over more neighbors and friendscan result in an epidemic phenomenon over the network. As this infection propagates, aninformation cascade will be generated. The spread of information cascades over social net-works forms the diffusion networks. Although observing the infection time of a person ispossible, determining the source of infection is usually a difficult problem. Additionally, inmany applications we can not observe the underlying network which diffusion...
Developing a Base Guideline for Cost Engineering System in Iranian Oil, Gas & Petrochemical Industry Projects
, M.Sc. Thesis Sharif University of Technology ; Eslami, Hossain (Supervisor)Nonlinear Controller Design for Stree-By-Wire Passenger Car
, M.Sc. Thesis Sharif University of Technology ; Kazemi, Reza (Supervisor)
Abstract
Today safety is one of the major competition factors in automotive industries . The vehicles of today are more and more dependent on electronic systems , for driving safety and ease on control for the driver . Some systems are more or less standard in vehicles on the market , examples of such systems are ABS , ABC , etc. Despite of the effect of these systems on vehicle dynamics ,because they only control longitudinal dynamics and don't receive any feedback from vehicle lateral behavior , now control systems ,named VDC , have been developed and implemented in advanced vehicles. The operation of such systems is as this that in any time instance they evaluate vehicle dynamical behavior....
A misbehavior‐tolerant multipath routing protocol for wireless Ad hoc networks [electronic resource]
, Article International Journal of Research in Wireless Systems (IJRWS) ; Vol. 2, Issue 9, pp. , Sep. 2013 ; Pakravan, Mohammad Reza ; Aref, Mohammad Reza ; Sharif University of Technology
Abstract
Secure routing is a major key to service maintenance in ad hoc networks. Ad hoc nature exposes the network to several types of node misbehavior or attacks. As a result of the resource limitations in such networks nodes may have a tendency to behave selfishly. Selfish behavior can have drastic impacts on network performance. We have proposed a Misbehavior-Tolerant Multipath Routing protocol (MTMR) which detects and punishes all types of misbehavior such as selfish behavior, wormhole, sinkhole and grey-hole attacks. The protocol utilizes a proactive approach to enforce cooperation. In addition, it uses a novel data redirection method to mitigate the impact of node misbehavior on network...
Numerical Investigation of Particle Distribution in Clean Room
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Hassan (Supervisor)
Abstract
These days, according to increasing requirement to the applications of clean rooms in industries in and within the developing industry of computer, positive indicators that show a real need to a compere comprehensive study and research about the Clean rooms, in oder to predict the distribution and dispersal of the particles. Correct determination of indoor airflow and particle concentration distribution results in new standard development for Clean rooms. As computational fluid dynamics has become a powerful tool for indoor airflow studies, in this research, influence of effective parameters on the flow and concentration distribution in clean rooms has been...
Structural-Geotechnical Interactions in Piled Raft Foundations (Prf) Design for High Rise Buildings Under Earthquake Loading
, M.Sc. Thesis Sharif University of Technology ; Ahmadi, Mohammad Mehdi (Supervisor)
Abstract
It has been realized that the raft (mat) foundations are capable of bearing very large loads when they are assisted with a pile group. The contribution of both raft and piles to carry the surcharge loads is taken into account, considering the stiffness and strength of involved elements in the system, i.e. piles, raft and surrounding soil. Piles are usually required to ensure the stability of the foundation and to act as settlement reducers especially for high rise buildings. The present study focuses on both kinematic and inertial effects of piled foundations and piled raft foundations under earthquake loading. The Finite Element Method (FEM) via ABAQUS will be used as an appropriate tool to...
Synergy of Energy Transition of Iran and China Under 25-year Cooperation Agreement
, M.Sc. Thesis Sharif University of Technology ; Maleki, Abbas (Supervisor)
Abstract
The Iran-China 25-year Cooperation Program on the further economic development particularly energy area signed on 27 March 2021 by Iran, which suffered from many years of political and economic isolation and China, the second global economy. Energy transition is an essential issue in both country's energy systems which calls for a medium energy carrier that will be the natural gas. China is seeking for new natural gas resources in order to achieve its ambitious net-zero goals and Iran has targeted 50% reduction in its energy intensity. The necessity of supplying the natural gas for Pakistan and China through the CPEC (China-Pakistan Economic Corridor) by Iran is an important criterion in the...
Air Flow and Respiratory Gas Exchange Simulation in Acinar Region of Human Lung
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Saeed (Supervisor)
Abstract
The main function of respiratory system is to exchange gasses between air and blood. However selection of the suitable geometry and solution of the fluid flow precede all other phenomena in the lung, including particle deposition and gas exchange. The most complicated phenomena take place at the terminal generations of the lung which is known as acinar region. Due to small dimensions and inability to use experimental measurements, numerical simulations are adequate methods in this region. In the first part of this thesis a method is proposed to reduce the computational space and make it possible to model all acinar region, simultaneously. Results show that the characteristic of streamlines...
Investigation on Novel Methods of Precious Metals Recovery from Spent Catalysts
, M.Sc. Thesis Sharif University of Technology ; Kazemeini, Mohammad (Supervisor)
Abstract
High demand and price and restricted availability of Platinum Group Metals (PGMs) have made platinum recovery a major field of study for researchers and industries. Various methods have been introduced for this purpose. Ion exchange, leaching and liquid-liquid extraction (LLE) are just a few examples. Nowadays Solvent Extraction (SX) is one of the most challenging areas of study for platinum recovery from spent catalysts due to its simplicity and optimum cost. In this study, the commercial spent catalyst’s platinum was dissolved in aqua-regia after XRF analysis. Then it was extracted by the organic material Trioctylphosphineoxide diluted in toluene in the presence of Alkaline metal salts....
Automatic Labeling of Prosody in Persian Unmarked Speech
, M.Sc. Thesis Sharif University of Technology ; Eslami, Moharram (Supervisor) ; Bahrani, Mohammad (Co-Advisor)
Abstract
Prosodic annotations are used for locating and characterizing prominent parts in utterances as well as identifying and describing boundaries of coherent stretches of speech. Automatic detection and labeling of prosodic events in speech has received much attention in recent years since prosody is intricately bound to the semantics of the utterance. Recognition of prosodic events is important for spoken language applications such as automatic understanding and translation of speech. Moreover, corpora labeled with prosodic markers are essential for building speech synthesizers that use data-driven approaches to generate natural speech. Such databases are important to reach a better...
Phonetic Representation of Intonation in Persian Vocative Structures
, M.Sc. Thesis Sharif University of Technology ; Eslami, Moharram (Supervisor) ; Bahrani, Mohammad (Co-Advisor)
Abstract
This study investigates the intonational properties of vocative structure in standard Persian in the framework of Auto-segmental-metrical phonology. Pitch accent is one of the elements whithin this framework, that refers to the prominence in the utterance. In Persian all lexical units are stressed in their final syllable and there is a language-specific feature in Persian according to which pitch accents are aligned with lexically stressed syllables. Contrary to the said feature, previous studies claim that in vocative structure, it is the first syllable that is accented, due to the difference existed between intonation pattern of vocative structure compared to its citation form. The data...
Analysis and Improvement of Intrusion Detection Methods in Data Network Routers
, M.Sc. Thesis Sharif University of Technology ; Aref, Mohammad Reza (Supervisor) ; Pakravan, Mohammad Reza (Co-Advisor)
Abstract
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...