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kalantar-hojjatabadi--mohsen
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Theory and Simulation of Nonlinear Transmission Lines Using MOSFET Devices
, M.Sc. Thesis Sharif University of Technology ; Farzaneh, Forouhar (Supervisor)
Abstract
Nonlinear transmission line (NLTL) a guiding structure contains nonlinear elements. For discrete NLTLs, this structure is periodically loaded with nonlinear elements. In the structure of this line nonlinear elements such as ceramic capacitors, nonlinear magnetic elements, vector diodes, Mos transistors, etc can be used. With the rapid development of semiconductor devices and microwave band systems, the demand for implementation of NLTLs has increased. These lines provide wide band-width, cut-off frequencies over the hundreds of GHz and picosecond rise time for various systems.Among the applications of NLTL, the generation of high power RF pulses has attracted the most attention. In this...
Study of Caspian Energy Markets with Respect the Energy Demand Security of Caspian Countries
, M.Sc. Thesis Sharif University of Technology ; Maleki, Abbas (Supervisor)
Abstract
The promotion of oil and gas industry of a country or region requires foreign and long-term investments. Ensuring the security of demand is one of the major driving forces for increasing investments in oil and gas sectors.The status of the Caspian markets in terms of energy demand security is the main issue in this study. Just like security of supply, security of energy demand will not be affected by economic logic alone, but the combination of various factors should be considered; So in this study Combined criteria was developed.According to the horizons of policy making for the energy export of Caspian, 2015 year as the recent past, 2020 as the medium-term and 2030 as the long-term have...
Theoretical Investigation and Optimization of Effective Microbial Parameters of Different Biocatalyst in Microbial Fuel Cells System Using Genetic Algorithm
, M.Sc. Thesis Sharif University of Technology ; Yaghmaie, Soheila (Supervisor)
Abstract
Microbial fuel cell is one of the new technologies in the field of power generation from the organic energy resource. The fuel cell system in a process similar to chemical fuel cell generate electrical energy through oxidation of organic composition by uses of electrogenic microorganisms as biocatalyst. In this study the main object is providing a comprehensive mathematical model for the fuel cell system in micro-liter size. To achieve this purpose, we start to investigate properties of fuel cell system in this size. And according to the geometry of system we choose chemotactic equation for estimating hydrodynamic behavior of microorganism and using combination of conductive base and...
Modeling of microfluidic microbial fuel cells using quantitative bacterial transport parameters
, Article Journal of Power Sources ; Volume 342 , 2017 , Pages 1017-1031 ; 03787753 (ISSN) ; Yaghmaei, S ; Kalantar, M ; Sharif University of Technology
Elsevier B.V
2017
Abstract
The objective of present study is to analyze the dynamic modeling of bioelectrochemical processes and improvement of the performance of previous models using quantitative data of bacterial transport parameters. The main deficiency of previous MFC models concerning spatial distribution of biocatalysts is an assumption of initial distribution of attached/suspended bacteria on electrode or in anolyte bulk which is the foundation for biofilm formation. In order to modify this imperfection, the quantification of chemotactic motility to understand the mechanisms of the suspended microorganisms’ distribution in anolyte and/or their attachment to anode surface to extend the biofilm is implemented...
A novel model for predicting bioelectrochemical performance of microsized-MFCs by incorporating bacterial chemotaxis parameters and simulation of biofilm formation
, Article Bioelectrochemistry ; Volume 122 , 2018 , Pages 51-60 ; 15675394 (ISSN) ; Mardanpour, M. M ; Yaghmaei, S ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Bacterial transport parameters play a fundamental role in microbial population dynamics, biofilm formation and bacteria dispersion. In this study, the novel model was extended based on the capability of microsized microbial fuel cells (MFCs) as amperometric biosensors to predict the cells' chemotactic and bioelectrochemical properties. The model prediction results coincide with the experimental data of Shewanella oneidensis and chemotaxis mutant of P. aeruginosa bdlA and pilT strains, indicating the complementary role of numerical predictions for bioscreening applications of microsized MFCs. Considering the general mechanisms for electron transfer, substrate biodegradation, microbial growth...
Backup Protection by Wide Area Measurement System
, M.Sc. Thesis Sharif University of Technology ; Ranjbar, Ali Mohammad (Supervisor)
Abstract
The traditional backup protection system of transmission lines are self-contained and only use from local measurements and generally, don’t use from wide area measurements. Hence, it can misoperate when the power system is extremely under stress conditions. So, the zone 3 of distance relays have been recognized as one of important participating causes of cascading phenomena that lead to major power system blackouts. In modern societies, power systems have become one of most important critical infrastructures, accordingly, blackouts can have catastrophic effects. Therefore, the novel backup protection schemes are required to improve security and dependability of protection system.
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Robust energy management of residential energy hubs integrated with power-to-x technology
, Article 2021 IEEE Texas Power and Energy Conference, TPEC 2021, 2 February 2021 through 5 February 2021 ; 2021 ; 9781728186122 (ISBN) ; Khoshjahan, M ; Saravi, V. S ; Kalantar, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
Growing interest in the intermittent renewable energy sources may jeopardize the flexibility of power systems. In order to improve the flexibility of modern power systems, the surplus electricity generated by renewable sources can be deployed into several carriers, such as natural gas and heating energy via power-to-gas (PtG) and power-to-heat (PtH) technologies. This paper proposes an optimal daily energy management model of residential energy hubs integrated with power-to-X technologies. The proposed energy hub is incorporated with PtG, PtH, combined heat and power (CHP) facilities, and thermal storage to meet the required electrical, gas, and heating demands. In order to capture the...
High-Efficiency Inertial Separation of Microparticles Using Elevated Columned Reservoirs and Vortex Technique for Lab-on-a-Chip Applications
, Article ACS Omega ; Volume 8, Issue 31 , 2023 , Pages 28628-28639 ; 24701343 (ISSN) ; Hajghassem, H ; Kalantar, M ; Karimi, A ; Tabatabaei Asl, M ; Hosseini, S ; Badieirostami, M ; Sharif University of Technology
American Chemical Society
2023
Abstract
The discovery of circulating tumor cells (CTCs) has envisioned an excellent outlook for cancer diagnosis and prognosis. Among numerous efforts proposed for CTCs isolation, vortex separation is a well-known method for capturing CTCs from blood due to its applicability, low sample volume requirement, and ability to retain cell viability. It is a label-free, passive, low-cost, and automated method, making it an ideal solution for lab-on-a-chip applications. The previous designs that employed vortex technology have shown reaching high throughput and 70% separation efficiency although it was after three processing cycles which are not desired. Inspired by our earlier design, in this work, we...
Sole versus dual-sourcing under order dependent lead-times and prices [electronic resource]
, Article Computers And Operations Research, Published in: Elsevier Journals ; Volume 36, Issue 12, December 2009, Pages 3272–3280 ; Eshghi, Kourosh ; Sharif University of Technology
Abstract
In this paper, we consider a dual-sourcing model with constant demand and stochastic lead times. Two suppliers may be different in terms of purchasing prices and lead-time parameters. The ordering takes place when the inventory level depletes to a reorder level, and the order is split among two suppliers. Unlike previous works in the order splitting literature, the supply lead time between vendor and buyer as well as unit purchasing prices is considered to be order quantity dependent. The proposed model finds out the optimal reorder point, order quantity and splitting proportion, using a solution procedure. Numerical results show that neglecting the relationship between ordering batch size...
Human serum protein adsorption onto synthesis nano-hydroxyapatite
, Article Protein Journal ; Volume 31, Issue 2 , February , 2012 , Pages 150-157 ; 15723887 (ISSN) ; Massah Bidgoli, M ; Behrashi, M ; Mohsen Nia, A ; Sharif University of Technology
2012
Abstract
Adsorption of human serum proteins (Albumin and total protein) onto high purity synthesis nano-hydroxyapatite (HA), Ca 10(PO 4) 6(OH) 2, has been studied in a wide temperature range by UV-visible spectrophotometer. Adsorption isotherm is basically important to describe how solutes interact with adsorbent, andiscriticalinoptimizing the use of adsorbent. Inthe present study, the experimental results werefitted tothe Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (DR) models to obtain the characteristic parameters of each model and square of the correlation coefficients (R 2). According to the results, the DR isotherm model had the best agreement with the experimental data. The effect of...
Effective Permeability of Isotropic Overlapping Sandbodies in 2D Using Percolation Theory
, M.Sc. Thesis Sharif University of Technology ; Masihi, Mohsen (Supervisor)
Abstract
Permeability is an essential parameter used for reservoir evaluation, simulation and management to optimize oil recovery. The conventional approach to estimate reservoir connectivity, conductivity, sweep efficiency and other critical information for decision-making is to build detailed geological models, which are then upscaled to a coarser grid where flow simulations are run. However, this takes many hours to be carried out even for a single realization practically. In practice, a very small number of realizations are considered and consequently the true uncertainty in the results is very poorly estimated. In this study, a statistical model of isotropic overlying sandbodies is used to...
A Metabonomics Study of Samples of Different Diseases: Investigation of Linear and Non-Linear Model by Nuclear Magnetic Resonance
, Ph.D. Dissertation Sharif University of Technology ; Tafazzoli, Mohsen (Supervisor)
Abstract
Metabonomics is a quantitative measurement of time dependent metabolic interactions for living systems in response to the pathological or genetic variations. NMR spectroscopy has emerged as a key tool for understanding metabolic processes in living systems. In this project, the study of metabolomics was performed as classification and regression on samples of parkinson’s disease, multiple sclerosis disease, celiac disease and crohn’s disease. In classification part, various methods were applied using optimal parameters.classification methods in Parkinson’s disease, multiple sclerosis disease, celiac disease and crohn’s disease were RF, CART, PLS-DA, RF and RF respectively. Based on the...
Determination of Parameters Affecting the Linear Seismic Evaluation of Gravity Dams Using Nonlinear Analysis
, M.Sc. Thesis Sharif University of Technology ; Ghaemian, Mohsen (Supervisor)
Abstract
Gravity dams are solid concrete structures that maintain their stability against design loads from the geometric shape and the mass and strength of the concrete. Because of their critical role in supplying portable and agricultural water and problems which would happen if they broke, it is required to consider their stability and keep them in safe conditions. They should be able to continue their function after a disaster such as earthquake. But most of them are aged dams with some have been built near faults. Indeed, there are some concerns regarding the performance of these dams under the effect of seismic loads. This research deals with performance evaluation of concerete gravity . The...
Numerical Analysis of Soil-Nailed Walls in Seismic Condition
,
M.Sc. Thesis
Sharif University of Technology
;
Haeri, Mohsen
(Supervisor)
Abstract
Soil nailing is an in-situ technique of mechanically stabilizing soil masses which has been used in France, Germany, United states, and recently in Iran. A review of literature shows that Soil-Nailed walls have performed well during strong ground motions in comparison with the gravity retaining structures. After the 1989 Loma Prieta earthquake, minor signs of distress or corresponding deformation were found on the Soil-Nailed walls, indicating excellent performance of such structures during moderate and strong shakings. These observations indicate that Soil-Nailed walls have an inherent satisfactory seismic response. This has been attributed to the intrinsic flexibility of the Soil-Nailed...
Collapsible Behavior of Gorgan Loess Using Odeometer
, M.Sc. Thesis Sharif University of Technology ; Haeri, Mohsen (Supervisor)
Abstract
In nature, there are types of soils that when goinging under stress at constant moisture, or increase of moisture at constant stress, or change of both characters, they show a sudden and high level decrease in their volume. These type of soils are named as Collapsible soils. Iran is one of the countries that at some parts of its land collapsible soils are found. In this research by using of laboratory equipments, the volume change behavior of collapsible loess soils of Gorgan plain (North of Iran) is evaluated under increase of water content and inundation stress. In these experiments, the usual odeometer cell has been used for exploring the behaviour of collapsibility and volume change of...
The Effect of Cementation by Lime on Collapsible Soils Behavior Using Suction Controlled Oedometer Device Case Study: Loess of Gorgan
, M.Sc. Thesis Sharif University of Technology ; Haeri, Mohsen (Supervisor)
Abstract
Collapsible soils such as loess, which are naturally found unsaturated, are kind of problematic soils that undergo sudden and noticeable decrease in volume under increasing stress at constant moisture, increasing moisture at constant stress, or increase in both of them. This kind of soil can be found in some parts of Iran such as plain of Gorgan. To fulfill the main purpose of this study, evaluating the effect of cementation on collapse behavior of loess of Gorgan, some oedometer tests under controlled matric suction were performed on reconstituted samples without and with lime. The lime was added for stabilizing of the collapsible materials and the amount was chosen to be %3 by weight of...
An Experimental Investigation of Three-Phase Flow of water-Oil-Gas Mixture Through Water-wet Sandstone
, M.Sc. Thesis Sharif University of Technology ; Masihi, Mohsen (Supervisor)
Abstract
Accurate prediction of relative permeability for various reservoir rocks at various saturation conditions has been of concern for a long time in petroleum industry. Relative permeability is known as one of the most significant parameters in simulation of actual multi-phase flow through porous media during life-time of a hydrocarbon reservoir. In addition, it plays important role in oil production and well completion. Direct experimental measurement in order to determine relative permeability of porous rock has long been recorded in petroleum related literature. However, empirical methods for determining relative permeability are becoming more widely used, particularly with the advent of...
Introducing a Set of Material Strain Measures in Non-Linear Kinematics of Micropolar Continuum Mechanics and Determining their Time Rates
, M.Sc. Thesis Sharif University of Technology ; Asghari, Mohsen (Supervisor)
Abstract
The concept of generalized strains is a well-established subject in the classical continuum mechanics. The characteristics and various applications of the generalized strains have been the point of interest of many researchers in the classical continuum mechanics. The aim of this thesis is the introduction of generalized strains in the micropolar theory, as a non-classical continuum theory. A set of generalized strains is suggested for the deformation of macro-elements. Moreover, a set of generalized strains is proposed for the micro-structures. Since the rate of strains possesses a significant importance in the constitutive equations of nonlinear analysis of solids, expressions for the rate...
Evaluation of the Behaviour of Collapsible Soils in Saturated and Unsaturated Oedometer Tests – Case Study of Gorgan Loess
, M.Sc. Thesis Sharif University of Technology ; Haeri, Mohsen (Supervisor)
Abstract
Collapsible soils are kinds of problematic soils which are susceptible to large and sudden reduction in volume upon wetting. A manifest kind of these soils is loess; catastrophic settlement of structures which are built upon it has been observed when the soil becomes wet. In this investigation the collapse potential of samples of loess taken from Gorgan, Golestan, Iran, has been studied by using unsaturated odometer tests under controlled matric suction. To this end, two modified odometer apparatus with the capability of controlling the matric suction, have been designed and developed. Undisturbed samples of soil have been tested under K0 condition, while the matric suction, volumetric...