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    Observer Design for Exhaust Manifold Pressure in Turbocharged SI Engines

    , M.Sc. Thesis Sharif University of Technology Hassani Monir, Vahid (Author) ; Alasty, Aria (Supervisor) ; Vossoughi, Gholamreza (Supervisor)
    Abstract
    Nowadays, fuel optimum used in engines is an important matter. To achieve this aim, we need to tune engine. The big companies have paid attention to these cases. Because of it, there are strict standard in the world and in other side the internal combustion engine is very common.
    In the internal combustion engine after cylinder, the gas inter to an encasement which is called exhaust manifold. In the other hand, exhaust manifold is in upstairs of turbine and waste-gate in turbocharged SI engines. To control fuel used and descries the amount of emissions, exhaust manifold pressure is very important. In the other hand, monitoring of exhaust manifold pressure can use for fault detection of... 

    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... 

    Real-time estimation of the volumetric efficiency in spark ignition engines using an adaptive sliding-mode observer

    , Article Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering ; Volume 229, Issue 14 , December , 2015 , Pages 1925-1933 ; 09544070 (ISSN) Hassani Monir, V ; Salehi, R ; Salarieh, H ; Alasty, A ; Vossoughi, G ; Sharif University of Technology
    SAGE Publications Ltd  2015
    Abstract
    Proper operation of an engine requires accurate measurement or estimation of the engine's air charge provided to the control unit which reduces both the engine's fuel consumption and the emissions. The volumetric efficiency of the engine is a key variable in computations using the engine control unit to estimate the air charge using the speed-density equation. This paper presents a new approach for real-time estimation of the volumetric efficiency using the sliding-mode methodology. An adaptive sliding-mode observer is proposed which relies on measurements from the engine's conventional sensors. The observer is shown to estimate asymptotically the volumetric efficiency of the engine for... 

    Modelling of Frictional Cracks by the Extended Finite Element Method Considering the Effect of Singularity

    , M.Sc. Thesis Sharif University of Technology Saeed Monir, Saeed (Author) ; Khonsari, Vahid (Supervisor) ; Mohammadi, Soheil (Co-Advisor)
    Abstract
    When a crack is subjected to a compression field, it will close and its edges will get into contact with each other. Depending on the direction and magnitude of the loads and also the coefficient of friction, ‘stick’ or ‘slip’ situationsbetween the edges will occur. This type of crack is known as ‘frictional crack.’ In this project, first these cracks are studied analytically and the order of singularity is derived using asymptotic analysis and also the analytical fields are determined for both ‘isotropic’ and ‘orthotropic’ materials. Then, numerical simulations are carried out using extended finite element method which is considered as the most powerful means for analyzing the problems... 

    Analysis of the Effect of Economic Variables on Effectiveness of Mobile Sources Air Pollutants Emission Control Policies: in the Case of Tehran

    , Ph.D. Dissertation Sharif University of Technology Hassani, Amin (Author) ; Maleki, Abbas (Supervisor) ; Hosseini, Vahid (Co-Supervisor)
    Abstract
    Passenger cars (PCs) are of particular importance among mobile air pollutants emissions sources due to their population and significant share in air pollutants emissions and gasoline consumption. Moreover, ownership and use intensity of PCs are affected by socio-economic situation. The present study projects the future trends of air pollutants emissions and fuel consumption from PCs in Tehran by 1415 and assesses the effect of economic situation on the emission trends and effectiveness of emission reduction polices. Accordingly, the present study develops an interdisciplinary modeling framework, which combines econometric models with a bottom-up emission estimation model to simulate the... 

    The Effect of Vertical Excitation on the Response of Soil-Structure Systems Allowed to Uplift

    , M.Sc. Thesis Sharif University of Technology Monir Vaghefi, Zeinab (Author) ; Ghannad, Mohammad Ali (Supervisor)
    Abstract
    The simultaneous effect of uplift phenomenon and vertical vibration of soil-structure system is investigated in this study. The super-structure is modeled as an equivalent single-degree of freedom with bilinear behavior mounted on a rigid foundation resting on distributed tensionless Winkler springs and dampers. The effect of vertical excitation on the response of soil-structure systems allowed to uplift is investigated parametrically through time history analysis for a wide range of systems subjected to sine pulse and a group of ground motions recorded on the soil type of C. The results consist of maximum displacement of the uplifting system and ductility demand of the super-structure as a... 

    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... 

    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  

    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...