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    Vertical Forced Vibration of a Rigid Disk in a Transversely Isotropic Full-Space

    , M.Sc. Thesis Sharif University of Technology Hassani. Arash (Author) ; Eskandari, Morteza (Supervisor) ; Mohammadi Shodja, Hossein (Co-Advisor)
    Abstract
    This research is concerned with the investigation of forced time–harmonic vertical vibration of a rigid disk embedded in a transversely isotropic full space medium. By properties of integral transform methods, the generalized mixed boundary–value problem is formulated as a set of dual integral equations, which in turn, are reduced to a Fredholm equation of the second kind. The obtained Fredholm integral equation is solved by well-known numerical methods. Selected results for the load distribution on the disk and complex compliance are presented for various ranges of frequency.

     

    Nerve retraction during inferior alveolar nerve repositioning procedure: A new simple method and review of the literature

    , Article Journal of Oral Implantology ; Volume 41 , Dec , 2015 , Pages 391-394 ; 01606972 (ISSN) Hassani, A ; Saadat, S ; Moshiri, R ; Shahmirzad, S ; Hassani, A ; Sharif University of Technology
    Allen Press Inc  2015
    Abstract
    Nerve repositioning surgery is one of the treatments chosen for the patients with edentulous posterior atrophic mandible. Like any other treatments, this therapy has its advantages and disadvantages, indications and contraindications. The most important complication of this procedure is neurosensory disturbance. This problem may occur at different stages of the treatment. One common time when nerve damage happens is when the nerve is located outside the canal and drilling and insertion of the implant are performed. Accordingly, this report describes a simple and feasible method to retract and protect nerves outside the canal during the treatment of nerve transposition. This will reduce the... 

    Nerve retraction during inferior alveolar nerve repositioning procedure: a new simple method and review of the literature

    , Article The Journal of oral implantology ; Volume 41 , 2015 , Pages 391-394 ; 01606972 (ISSN) Hassani, A ; Saadat, S ; Moshiri, R ; Shahmirzad, S ; Hassani, A ; Sharif University of Technology
    2015
    Abstract
    Nerve repositioning surgery is one of the treatments chosen for the patients with edentulous posterior atrophic mandible. Like any other treatments, this therapy has its advantages and disadvantages, indications and contraindications. The most important complication of this procedure is neurosensory disturbance. This problem may occur at different stages of the treatment. One common time when nerve damage happens is when the nerve is located outside the canal and drilling and insertion of the implant are performed. Accordingly, this report describes a simple and feasible method to retract and protect nerves outside the canal during the treatment of nerve transposition. This will reduce the... 

    Thermal structure and energy budget for alghadir reservoir, iran

    , Article Water Resources ; Volume 40, Issue 6 , 2013 , Pages 621-630 ; 00978078 (ISSN) Hassani, A ; Sharif University of Technology
    2013
    Abstract
    Knowing the rate of evaporation from surface water resources such as channels and reservoirs is essential for precise management of the water balance. Few detailed evaporation studies exist for small lakes or reservoirs in arid regions of the world. In this study, monthly evaporation was determined by Bowen Ratio Energy Budget technique (BREB) for Alghadir reservoir (Saveh, Iran) from 1995-2007 and compared with class-A pan. Daily data were obtained from IMO (Iran Meteorological Organization) weather station, located near the reservoir, for all of these years. Some variations have been observed on the estimated evaporation of the energy budget at different years, ranging from 151 cm for 1997... 

    Ant colony algorithm for the shortest loop design problem [electronic resource]

    , Article Computers and Industrial Engineering, Elsevier ; Volume 50, Issue 4, August 2006, Pages 358–366 Eshghi, K. (Kourosh) ; Kazemi, Morteza ; Sharif University of Technology
    Abstract
    In this paper, a new algorithm for solving the shortest loop design problem is presented. The shortest loop design problem is to find the shortest loop for an automated guided vehicle covering at least one edge of each department of a block layout. In this paper, first it is shown that this problem can be represented as a graph model. The properties of the presented model enable us to design a meta-heuristic based on ant colony system algorithm for solving the shortest loop design problem. Computational results show the efficiency of our algorithm in compare to the other techniques  

    Robust Control of Satellites Formation Flying

    , M.Sc. Thesis Sharif University of Technology Hassani, Ali (Author) ; Saghafi, Fariborz (Supervisor)
    Abstract
    Recent developments in space industry and the great tendency for definition of efficient, precise and low cost missions are the main reasons for the growing interest in satellites formation flight. Regarding the aforementioned, the study of the multiple satellite control methods is the subject of the present project. In this project, the governing equations of motion of satellite formation flight are developed. Based on this development, it is shown that the satellite linear equations of motion like many other linear system presentations, can not sufficiently model the real system. Therefore, some of the most famous uncertainties in space dynamics such as semimajor axis and eccentricity... 

    Data Analysis of MOA for Gravitational Microlensing Events with Durations Less than 2 Days by Using Brown Dwarfs Population

    , M.Sc. Thesis Sharif University of Technology Hassani, Sheida (Author) ; Rahvar, Sohrab (Supervisor)
    Abstract
    Gravitational Microlensing is one of the most powerful methods of detecting very low mass objects like Exoplanets and Brown dwarfs. The most important parameter that we can extract from a microlensing event is Einstein radius crossing time t_E. In this thesis, with performing Monte-Carlo simulation, we will obtain t_E distribution for brown dwarf population. Then we will show that this population can be a good candidate for very short microlensing events with t_E<2 days. The data set used in this analysis was taken in 2006 and 2007 seasons by the MOA-II survey, with the 1.8-m MOA-II telescope located at the Mt. John University Observatory, New Zealand  

    Micro-modeling of Tehran 4-stroke Gasoline Motorcycle Fleet Emission and Investigating the Effects of Increasing Fueling System and Engine Technology Level

    , M.Sc. Thesis Sharif University of Technology Hassani, Amin (Author) ; Hosseini, Vahid (Supervisor)
    Abstract
    The city of Tehran is dealing with air pollution problems for years. Providing a solution for this problem requires information about different pollutants emission sources. In this subjects, emission factors and emission models are essential tools for decision makers. Among different mobile emission sources in Tehran, motorcycles are of high importance. In this project, for the first time in Iran, exhaust gas pollutants emission of 66 motorcycles with different ages and engine displacement volumes were measured according to Euro-3 standard certification procedure. Measurement results showed that none of the tested motorcycles passed the Euro-3 certification limit on CO emission. Calculations... 

    An assessment of gasoline motorcycle emissions performance and understanding their contribution to Tehran air pollution

    , Article Transportation Research Part D: Transport and Environment ; Volume 47 , 2016 , Pages 1-12 ; 13619209 (ISSN) Hassani, A ; Hosseini, V ; Sharif University of Technology
    Elsevier Ltd  2016
    Abstract
    Motorcycles are the third most common means of transportation in the megacity of Tehran. Hence, measurements of emission factors are essential for Tehran motorcycle fleets. In this study, 60 carburetor motorcycles of various mileages and engine displacement volumes were tested in a chassis dynamometer laboratory according to cold start Euro-3 emissions certification test procedures. For almost all of the tested samples, the average carbon monoxide (CO) emission factors were about seven times higher than the limits for Euro-3 certification. No motorcycle fell within the Euro-3 certification limit on CO emissions. 125 cc engine displacement volume motorcycles, which are dominant in Tehran,... 

    Studying the Factors Affecting Exchange-Traded Funds’ Tracking Errors in Tehran Stock Exchange Market

    , M.Sc. Thesis Sharif University of Technology Hassani, Hossein (Author) ; Bahramgiri, Mohsen (Supervisor)
    Abstract
    Exchange-Traded Funds (ETFs) have become an important innovation in the financial markets nowadays. They are low cost products designed to pursue different replication strategies that respond to investor’s demands of liquidity and efficiency. However, they suffer from tracking errors and price mismatches even when they are designed to avoid them. So this problem makes diffrence between return of these ETFs and Index return that will be called “Tracking Errors”. In this research, due to analysis on 7 ETFs in Tehran Stock Exchange (TSE) in the 20 months period and analysis on 8 different independent variables that was expected to affect on tracking errors, it has been showed that between four... 

    Quantum Estimation: Properties and Calculation of the Quantum Fisher Information and Adaptive Scheme

    , Ph.D. Dissertation Sharif University of Technology Hassani, Majid (Author) ; Rezakhani, Ali (Supervisor)
    Abstract
    In this thesis , we study quantum estimation , its primary tools and different approaches . To this end , along with reviewing the main concepts of classical and quantum estimation , the Cramer-Rao inequlity which establishes a lower bound on the precision of estimation has been used . This lower bound can be calculated using the quantum Fisher information . In order to explore properties of the quantum Fisher information , we study the continuity relation of this quantity in the most general case and we calculate it for different quantum states . To underline the importance of the continuity relation , one can demonstrate an estimate of the value of the quantum Fisher information... 

    Intersection Theory of Moduli Space of Stable N-Pointed Curves of Genus Zero

    , M.Sc. Thesis Sharif University of Technology Hassani, Mahyar (Author) ; Jafari, Amir (Supervisor)
    Abstract
    A moduli spase consists in classifying geometric objects up tp equivalence relations and its point are in 1-1 corrospondence with equivalence classes. One of the most important moduli spaces in algebraic geometry is «moduli space of stable n-pointed curves of genus zero» which has many applications in mathematics and theoretical physics.In [10] Knudsen shows that for every n 3 there is a smooth projective variety Xn that is a moduli space for stable n-pointed curves of genus zero.In this thesis we study moduli spaces and introduce Xn and its relation with cross ratios. This way we show Xn is smooth projective variety and a fine moduli space. [5] After that we study a paper by Sean Keel. [9]... 

    Projection of passenger cars’ fuel demand and greenhouse gas emissions in Iran by 2050

    , Article Energy Conversion and Management: X ; Volume 12 , 2021 ; 25901745 (ISSN) Hassani, A ; Maleki, A ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    Passenger cars (PCs) not only are a major contributor to greenhouse gas (GHG) emissions in Iran but also pose severe energy security challenges due to their dependence on gasoline. This study aimed to understand the future trends of the gasoline demand and GHG emissions from PCs in Iran and assess the effectiveness of mitigation policies. The data were collected from multiple sources and used to develop the survival rate function of PCs. The study used back-calculation to compensate for the short period of stock data availability. The use intensity of PCs was estimated based on the gasoline consumption statistics. Econometric models were developed to project the future PC stock and use... 

    Simulation of Monopile-Clay Soil Interaction for Offshore Wind Turbines

    , M.Sc. Thesis Sharif University of Technology Hassani, Mohammad (Author) ; Raie, Mohammad (Supervisor)
    Abstract
    Monopiles are large-diameter with a typical diameter of 2 to 10 meters that are used for the base of offshore wind turbines. During its life, this structure is subjected to wind, wave, and sea currents, and due to the lateral displacement of the monopile, the wind turbine base structure with a considerable height can create the effect of "P-Δ". Therefore, accuracy in modeling and accurate estimation of monopile displacements and rotations is important. At present, the lateral design of monopiles is based on force-displacement (p-y) curves. P-y curves are semi-empirical curves based on experimental results obtained on piles with a diameter of less than one meter in different soils and under... 

    Projection of passenger cars’ air pollutants and greenhouse gas emissions and fuel consumption in Tehran under alternative policy scenarios

    , Article Case Studies on Transport Policy ; Volume 10, Issue 4 , 2022 , Pages 2195-2207 ; 2213624X (ISSN) Hassani, A ; Maleki, A ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    Passenger cars (PCs) are a major contributor to urban air pollution, greenhouse gas emissions, and energy security challenges in megacities in developing countries because of their high growth potential. Since the PC fleet changes through time, the projection of air pollutant emissions from PCs is essential for effective emission reduction policymaking. However, the extensive amount of data and proper models are required for this purpose that are not available in many developing countries. Hence, this study develops multiple econometric and emission models and integrate them into a framework to simulate the future stock and activity of PCs and projects PCs’ air pollutants and CO2 emissions... 

    Design of a Wide Band Power Amplifier for Power DAC

    , M.Sc. Thesis Sharif University of Technology Hassani, Keyvan (Author) ; Sharifbakhtiar, Mehrdad (Supervisor)
    Abstract
    Today’s radio transmitters must be able to send information in several standards. One problem involved in these wide band electronic systems lies in its end part, ie power amplifier. To have a broad band width either switching must be made among several power amplifiers with narrow band width (tuned) or the transistor part of power amplifier must be the same and single and selection be made only among matching networks. In this thesis, a power amplifier with broad band width without requiring a matching network has been designed and laid out. Also considering the low breakdown voltage of the gate oxide of the today’s standard CMOS transistors, it is very difficult to get a high output power... 

    Developing an Off-the-Shelf microfluidic droplet generation device for cell encapsulation

    , Article Industrial and Engineering Chemistry Research ; Volume 61, Issue 30 , 2022 , Pages 10689-10699 ; 08885885 (ISSN) Hassani Gangaraj, M ; Shamloo, A ; Sharif University of Technology
    American Chemical Society  2022
    Abstract
    Droplet microfluidics is a platform of microfluidics in which two immiscible fluids are used to generate droplets for various biomedical applications. This platform introduces several advantages in applications such as cell lysis, cell culture, co-culture, and cell encapsulation. The most important issues regarding droplet generation devices are the fabrication complexity and maintenance of these devices. In this study, a simple and easy-to-fabricate microdroplet generator is designed and fabricated to resolve these issues. Furthermore, since this device is easy to fabricate and use, it can play a key role in the fabrication of medical devices for controlling infectious diseases in poor and... 

    Love Wave Propagation in a Functionally Graded Magneto-Electro-Elastic Half-Space with Quadratic Variations

    , M.Sc. Thesis Sharif University of Technology Nobahar, Masoud (Author) ; Eskandari, Morteza (Supervisor)
    Abstract
    The propagation behavior of Love wave in functionally graded magneto-electro-elastic half-spaces with a quadratic variation is addressed. The magneto-electromechanical coupling factor, the dispersion relations, electric potential, magnetic potential and displacement are obtained analytically for both magneto-electrically open and short conditions. The effect of gradient coefficient on phase velocity, group velocity and magneto-electromechanical coupling factor are plotted and discussed. Research on the wave propagation in magneto-electro-elastic materials is still very limited. This work provides us with a theoretical foundation to design and practically apply SAW devices with high... 

    Modeling Reaction and Distribution of Water in Nanopores of the Cathode Catalyst Layer of PEM Fuel Cell

    , M.Sc. Thesis Sharif University of Technology Nushak, Fatemeh (Author) ; baghalha, morteza (Supervisor)
    Abstract
    In the proton exchange membrane fuel cells (PEM, the produced water would be divided into two phases of vapor and liquid. distribution of both liquid and vapor phases in different cell layers affects the performance, the efficiency and the life of a fuel cell significantly. Moreover, Nano pores of the cathode catalyst layer are involved with some phenomena such as electrochemical reaction kinetics, heat and mass transfer and interface phase change. One of the most important problems in the performance of fuel cells is distribution of liquid water in the porous areas. Water flooding in fuel cells causes to delay in oxygen transport to active sites in the catalyst layer because the pores of... 

    Elastic Analysis of a Surface Stiffened Transversely Isotropic Half-space Under a Buried Horizontal Point Load

    , M.Sc. Thesis Sharif University of Technology Naghib, Hamed (Author) ; Eskandari, Morteza (Supervisor)
    Abstract
    In this study, the interaction between thin plate completely bonded to the transversely isotropic halfspace and a concentrated force applied horizontally (Mindlin-type force) are considered. This problem has been solved analytically. This problem is used as sample for thin solid films and surface coating technology, where the surface of solid is covered by thethin plate for increasing its stiffness. Moreover, this problem is a good sample when homogenous solid is subjected to contact loading and can be seen that mechanical properties of material which is near the solid surface varies; consequently, a two-phase solid is created.Because of the influence of noted inhomogeneity, solid is...