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Advanced Electromagnetics and Scattering Theory
, Book ; Khorasani, Sina
Springer
2015
Abstract
This book present the lecture notes used in two courses that the late Professor Kasra Barkeshli had offered at Sharif University of Technology, namely, . The prerequisite for the sequence is vector calculus and electromagnetic fields and waves. Some familiarity with Green's functions and integral equations is desirable but not necessary.
The book provides a brief but concise introduction to classical topics in the field. It is divided into three parts including annexes. Part I covers principle of electromagnetic theory. The discussion starts with a review of the Maxwell's equations in differential and integral forms and basic boundary conditions. The solution of inhomogeneous wave...
The book provides a brief but concise introduction to classical topics in the field. It is divided into three parts including annexes. Part I covers principle of electromagnetic theory. The discussion starts with a review of the Maxwell's equations in differential and integral forms and basic boundary conditions. The solution of inhomogeneous wave...
Customer Needs: Finding the Relationship Gaps Between IRAN Digital Print Industrry and Its Individual/Industrial Customers
, M.Sc. Thesis Sharif University of Technology ; Najmi, Manoochehr (Supervisor)
Abstract
Customer needs of Iran Print Industry have permanently been a secret for all producers, print centers and even many of the customers themselves. This research tries to find the relationship gaps between Iran Print Industry and its Individual /Industrial Customers, by identifying their needs. This will give recommendations on how manufacturers can increase their customers' satisfaction by providing them with what they need. Also it helps find the customers` satisfaction coefficient of the needs, which is a good guide for Customer Relationship Management in this industry.Therefore, manufacturers can spot these results by providing appropriate machines which can achieve these goals and offer...
The Effect of Surfactant Agents on the Superhydrophobic Properties of Silica Coatings Synthesis by Sol-gel
, M.Sc. Thesis Sharif University of Technology ; Dolati, Abolghasem (Supervisor)
Abstract
The purpose of this research is producing one phase silica superhydrophobic coating by sol-gel method and drying temperature less than 200 degrees. For preparing micrometer and nanometer scaled hierarchical structure based on silica, TEOS precursor and Fumed Silica nanoparticles were used by density of 43/30 cc/lit and 6/52 gr/lit in order to provide desired roughness in the range of 40 nm. Moreover, HMDS surface modifying agent was used for reducing the surface energy of coating, which is not a danger to the environment in comparison to the same substances. The best Contact Angle is 155 degree and the best Sliding Angle is less than 5 degree. For instance, it was created with the...
Coordinating a seller-buyer supply chain with a proper allocation of chain’s surplus profit using a general side-payment contract [electronic resource]
, Article International Journal of Industrial and Systems Engineering ; Volume 5, No. 2, Summer 2011, Page 63-79 ; Eshghi, Kourosh ; Sharif University of Technology
Abstract
In this paper, seller-buyer supply chain coordination with general side-payment contracts is introduced to gain the maximum possible chain profit. In our model, the logistics costs for both buyer and seller are considered and the final demand is also supposed to be a decreasing function of the retail price. Since parties aim to maximize their individual profits, the contractual parameters are set in a way that these decisions become aligned with system optimal decisions. Therefore, a side payment contract is suggested in our model to assign the chain surplus profit to the chain members such that they have no intention to leave the coalition. Then, we change the contract into a quantity...
Design and Analysis of Delay Lines Based on Photonic Crystal Coupled Cavities
, M.Sc. Thesis Sharif University of Technology ; Khorasani, Sina (Supervisor)
Abstract
In the recent years, photonic crystal (PhC) devices vastly have been paid attention due to their ignorable loss, very low group velocity, flexibility in shape and dimension.In this thesis a PhC coupled cavity ring known as superresonator is introduced and its properties and applications is studied. Also modes of the structure are extracted through both coupled-resonator model and FDTD method, and two of its application is described and studied. Add-drop filter is one of the essential devices in WDM systems. First, an application of superresonator in designing add-drop filters is explained and a novel filter based on the superresonator is introduced and analyzed by FDTD and coupled mode...
Photonic Crystal Cavity Quantum Optic in the Very Strong Coupling Regime
, M.Sc. Thesis Sharif University of Technology ; Khorasani, Sina (Supervisor)
Abstract
First, we peruse the intraction between a quantized light and a two level atom which has been described by Janes-Cummings-Paul Hamiltonian. By solving Heisenberg equations in Fourier space and describing electric field by a generalized-transverse Green function, we obtain spectral density for a quantum dot which is in the strong coupling to a slab photonic crystal cavity. Afterward, by solving Shrouding equations precisely we demonstrate when quantum dot is in a very strong coupling to cavity, rotate wave approximation is not reliable anymore. It means that if coupling constant gets comparable to cavity mode frequency then the prevalent approach to solve this Hamiltonian will not be correct....
Cavity Quantum Electro-Dynamics in Ultra-Strong Coupling Regime
,
M.Sc. Thesis
Sharif University of Technology
;
Khorasani, Sina
(Supervisor)
Abstract
Cavity Quantum Electro-Dynamics (CQED) in Weak, Strong and Ultra-Strong coupling Regimes are studied. A MATLAB m-file is written which is able to solve any arbitrary CQED configuration. This program demands input data such as number of Quantum Dots, number of energy levels of each Quantum Dot, energies of each energy level of Quantum Dots, Number of cavity modes, eign-frequency of each cavity mode, coupling constant, dipole strength of each allowed transition of Quantum Dots and initial state of system from user and begins to solve the Schrodinger equation for annihilation and atomic ladder operators. In addition, coefficients of each possible ket will be calculated. Since, any approximation...
Analysis of Ultra-Strong Coupling in Optical Waveguides
, M.Sc. Thesis Sharif University of Technology ; Khorasani, Sina (Supervisor)
Abstract
In this project, we were intended to study the ultra-strong coupling in optical waveguides. Hence, we analyze the interaction of an electromagnetic wave with a quantum well embedded in a dielectric slab waveguide. First, we designed a QW with and alloys, which the energy of its electron-heavy holes transition is . By exploiting the envelope function approximation, we derived the wavefunction of electrons and holes, their eigen-energies, and the dipole moment of electon-holes. For finding the wavefunction of holes and their eigen-energies, we used the Luttinger Hamiltonian. Next, we calculated the electrical susceptibility of a three level quantum system (as a model for QW), by using...
Nonlinear Torsional Vibrations of Thin Walled Beam with Semi-Analytic Methods
, Ph.D. Dissertation Sharif University of Technology ; Haddadpour, Hassan (Supervisor)
Abstract
Thin Walled Beams are widely used in engineering applications with the minimum weight design criteria, ranging from civil to aerospace and many other industrial fields. The weight reduction of the beam leads to importance of the dynamic behavior of the structure. Frequently used thin walled beams have low torsional stiffness and their torsional deformations may be of such magnitudes that it is not adequate to treat the angles of cross section rotation as small. When the vibration amplitudes are moderate or large, the geometric nonlinearity must be included and some new phenomena which do not exist in linear torsional dynamic come into play. Unfortunately, the equations of motion of nonlinear...
Axial-torsional vibrations of rotating pretwisted thin walled composite beams
, Article International Journal of Mechanical Sciences ; Vol. 80 , 2014 , pp. 93-101 ; ISSN: 00207403 ; Haddadpour, H ; Sharif University of Technology
2014
Abstract
Axial-torsional vibrations of rotating pretwisted thin-walled composite box beams exhibiting primary and secondary warping are investigated. Considering the nonlinear strain-displacement relations, the coupled nonlinear axial-torsional equations of motion are derived using Hamilton's principle. Ignoring the axial inertia term leads to differential equation of motion in terms of elastic torsion in the case of axially immovable beams. Centrifugal load in the presence of material anisotropy and pretwist angle leads to an induced static torque. The nonlinear equation should be linearized about the corresponding equilibrium state to obtain the linear differential equation of motion. Extended...
Comment on "vibration of turbomachinery rotating blades made-up of functionally graded materials and operating in a high temperature field" by S-Y. Oh, L. Librescu and O. Song (Acta Mech. 166, 69-87, 2003)
, Article Acta Mechanica ; Volume 218, Issue 3-4 , 2011 , Pages 375-376 ; 00015970 (ISSN) ; Haddadpour, H ; Sharif University of Technology
2011
Response to the Authors' reply to the Comment on "vibration of turbomachinery rotating blades made-up of functionally graded materials and operating in a high temperature field", doi:10.1007/s00707-010-0407-5
, Article Acta Mechanica ; Volume 218, Issue 3-4 , 2011 , Pages 379-382 ; 00015970 (ISSN) ; Haddadpour, H ; Sharif University of Technology
2011
Comparative Study on Effect of Metallic Yield Dampers and Friction Devices on Response of Steel Structure
, M.Sc. Thesis Sharif University of Technology ; Kazemi, Mohammad Taghi (Supervisor)
Abstract
Passive energy dissipation systems are mechanical devices which could spread input energy, reduce response and decrease possible damage of the structure. Dampers were identified as a strong energy dissipation devices with cost efficiency and easy installation and maintanance. In this study, effects of using friction and metallic yield dampers to reduce structural responses are investigated. In addition, a comparison between these devices for reducing responses are conducted. Two 5 and 10 stories buildings with intermediate steel moment frames with and without damper are modeled and designed. It is seen, using of dampers could be reduce sections’ sizes. Seven pairs of earthquake records...
Biodesulfurization of dibenzothiophene by a newly isolated Rhodococcus erythropolis strain
, Article Bioresource Technology ; Volume 101, Issue 3 , 2010 , Pages 1102-1105 ; 09608524 (ISSN) ; Vosoughi, M ; Ziaee, A. A ; Sharif University of Technology
2010
Abstract
A new dibenzothiophene (DBT) desulfurizing bacterium was isolated from oil-contaminated soils in Iran. HPLC analysis and PCR-based detection of the presence of the DBT desulfurization genes (dszA, dszB and dszC) indicate that this strain converts DBT to 2-hydroxybiphenyl (2-HBP) via the 4S pathway. The strain, identified as Rhodococcus erythropolis SHT87, can utilize DBT, dibenzothiophene sulfone, thiophene, 2-methylthiophene and dimethylsulfoxide as a sole sulfur source for growth at 30 °C. The maximum specific desulfurization activity of strain SHT87 resting cells in aqueous and biphasic organic-aqueous systems at 30 °C was determined to be 0.36 and 0.47 μmol 2-HBP min-1 (g dry cell)-1,...
Gender Earnings Gap Among Tapsi Ride-share Drivers
, M.Sc. Thesis Sharif University of Technology ; Madanizadeh, Ali (Supervisor) ; Joshaghani, Hossein (Co-Supervisor)
Abstract
Some have argued that two-way markets, such as the online rideshar-ing platforms, which divide their services into different segments and provides each of these segments to the independent workforce based on an articulate and transparent income criterion, are more attrac-tive to women, which in turn, can reduce income disparities. This is due to the flexibility in working hours as well as the transparency of the labor payment process. In this study, using micro-data related to the trips of male and female drivers of Tap30, we find out that there is a 2.2 % gender earning gap between drivers. Furthermore, the fac-tors affecting the possible income difference are identified. On the one hand,...
Enhancing the Accuracy of Automotive Integrated Navigation System Using High-Order Error Model of Inertial Sensors Utilizing Auxiliary Sensors
, M.Sc. Thesis Sharif University of Technology ; Salarieh, Hassan (Supervisor)
Abstract
Navigation in various systems for land, air and sea movement has been of special importance for a long time. Determining the location, direction, speed and acceleration of moving has been a vital issue for mankind and it is also a basic prerequisite for starting the control process. Various methods have been used for this problem, the most important of which is the global positioning system. This method is satellite-based and any user from any part of the world can perform positioning. But in some places, such as tunnels or crowded places in the city, where it is not possible to send a signal, other methods are used. Also, in order to reduce errors, we can use the inertial navigation system...
Herschel-Bulkley rheological parameters of lightweight colloidal gas aphron (CGA) based fluids
, Article Chemical Engineering Research and Design ; Volume 93 , 2015 , Pages 21-29 ; 02638762 (ISSN) ; Arabloo, M ; Ghazanfari, M. H ; Rashtchian, D ; Sharif University of Technology
Institution of Chemical Engineers
2015
Abstract
The proper understanding of rheological characteristics of CGA based fluids is of crucial importance in determining the performance of the fluid, in order to maintain the most effective fluid properties for safe, efficient, and economical drilling operation. This paper presents a concise investigation on the effect of concentration of the three main components of a novel environmentally friendly lightweight CGA based drilling fluid, i.e., xanthan gum biopolymer, starch, and biosurfactant, to the Herschel-Bulkley rheological model parameters. The three parameters of Herschel-Bulkley model, i.e., yield stress, fluid consistency, and fluid flow index were calculated by fitting the experimental...
Transistor Based on Graphane
, M.Sc. Thesis Sharif University of Technology ; Khorasani, Sina (Supervisor)
Abstract
In the recent years, field effect transistor has been made by using graphane. But there has not been any study about bipolar transistor. Bipolar transistor can’t be constructed using graphene due to the fact that its band gap is zero. So in this thesis, in an attempt to remove this difficulty, the bipolar transistor made using graphane has been investigated and their property has been compared to those of three dimensional silicon transistors.
At the beginning of the thesis, we will have a review of graphane diode and will consider the procedure for evaluating its current which would be the report of what has been done sofar. After that we made graphane transistor using graphane diode...
At the beginning of the thesis, we will have a review of graphane diode and will consider the procedure for evaluating its current which would be the report of what has been done sofar. After that we made graphane transistor using graphane diode...
Behavior Patterns Analysis of Cavity Quantum Electro-Dynamics in Complex Systems for Different Coupling Regimes
, M.Sc. Thesis Sharif University of Technology ; Khorasani, Sina (Supervisor)
Abstract
In this M.Sc. thesis the behavior patterns of the cavity quantum electrodynamics of complex systems are analyzed, such systems are quantum optic multi-partite systems and consist of an arbitrary number of quantum dots in interaction with arbitrary number of cavity modes.
First, the coefficients matrix of the ket sate of the system was measured, in order to achieve it; the general time-dependent state of the most general possible system was specified. Its related Hamiltonian was written, and finally the Schrodinger equation was measured in different coupling regimes. It was done in Schrodinger picture without any approximation.Second, the presence probabilities of the quantum dots of any...
First, the coefficients matrix of the ket sate of the system was measured, in order to achieve it; the general time-dependent state of the most general possible system was specified. Its related Hamiltonian was written, and finally the Schrodinger equation was measured in different coupling regimes. It was done in Schrodinger picture without any approximation.Second, the presence probabilities of the quantum dots of any...
Effects of resistive loads and tire inflation pressure on tire power losses and CO2 emissions in real-world conditions
,
Article
Applied Energy
;
2015
;
ISSN: 03062619
; Nasiri, S
; Karkhaneh, V
;
Sharif University of Technology
2015
Abstract
Considerable portion of energy losses in a vehicle traced to tire. Energy losses in a tire are due to tire longitudinal slip as well as rolling resistance. Hence, both of aforementioned factors must take into the consideration to study the tire energy loss. Present paper aims to investigate the power losses in tires and to examine influence of road conditions and tire inflation pressure on them. To cover the real-world conditions, experiments were done on a gasoline-fueled passenger vehicle on an urban highway along two routes with same length and opposite gradients to comprise the change of road conditions. Then, by use of engine performance model which is prepared in dynamometer...