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jomeh-farsangi--mahya
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Energy Efficient Routing for Wireless Sensor Networks in Oil and Gas Pipelines
, M.Sc. Thesis Sharif University of Technology ; Mortazavi, Mohammad (Supervisor)
Abstract
Wireless sensor networks have many applications one of which in linear structure is used to control pipeline infrastructure. This thesis focuses on the routing of oil, gas, and water pipelines using wireless sensor networks. There are two algorithms one of which is Jump Always (JA) Algorithm and the other one is Redirect Always (RA) Algorithm. There are designed in Linear Structure of wireless sensor networks that are presented with a hierarchical addressing scheme. A Redirect Jump (RJ) routing protocol is our method that is designed for the hierarchical addressing scheme too. The RJ routing protocol has many benefits compared to the two methods (JA and RA). The RJ algorithm can increase the...
An analytical solution for dynamic behavior of thick doubly curved functionally graded smart panels
, Article Composite Structures ; Vol. 107, issue , January , 2014 , p. 88-102 ; Askari Farsangi, M. A ; Sharif University of Technology
2014
Abstract
In this paper, an analytical solution is presented for free vibration and dynamic behavior of doubly curved laminated shell consisting of a functionally graded core layer and surface attached functionally graded piezoelectric layers. Shell through-thickness kinematics is based on higher order shear deformation theory of shells, whereas a quadratic variation is assumed for electric potential. Using Hamilton's principle and Maxwell's equation, the governing equations of motion under mechanical loads are derived as seven highly coupled partial differential equations. Implementing Laplace transformation, doing few mathematical operations and using Laplace inverse method, time dependencies of...
Frequency-dependent energy harvesting via magnetic shape memory alloys
, Article Smart Materials and Structures ; Volume 24, Issue 11 , October , 2015 ; 09641726 (ISSN) ; Askari Farsangi, M. A ; Sharif University of Technology
Institute of Physics Publishing
2015
Abstract
This paper is focused on presenting an accurate framework to describe frequency-dependent energy harvesting via magnetic shape memory alloys (MSMAs). Modeling strategy incorporates the phenomenological constitutive model developed formerly together with the magnetic diffusion equation. A hyperbolic hardening function is employed to define reorientation-induced strain hardening in the material, and the diffusion equation is used to add dynamic effects to the model. The MSMA prismatic specimen is surrounded by a pickup coil, and the induced voltage during martensite-variant reorientation is investigated with the help of Faraday's law of magnetic field induction. It has been shown that, in...
Acoustic energy harvesting via magnetic shape memory alloys
, Article Journal of Physics D: Applied Physics ; Volume 52, Issue 13 , 2019 ; 00223727 (ISSN) ; Zohoor, H ; Sharif University of Technology
Institute of Physics Publishing
2019
Abstract
This study investigates acoustic energy harvesting via magnetic shape memory alloys (MSMA). The acoustic pressure impacts the neck of a Helmholtz resonator (HR) with a flexible face made of an elastic membrane. The design of the proposed energy harvester let radial force in the membrane be tunable. An MSMA is clamped to the membrane, and a proof mass is attached to the other end. The enhanced sound pressure vibrates the membrane and, therefore, excites the base of the MSMA specimen made of Ni-Mn-Ga to apply strain to it. Inserting strain onto the MSMA leads to variant reorientation and change of magnetization vectors, resulting in a change in flux passing through the pick-up coil. Therefore,...
A tunable helmholtz resonator for electromagnetic energy harvesting
, Article Proceedings of the 6th RSI International Conference on Robotics and Mechatronics, IcRoM 2018, 23 October 2018 through 25 October 2018 ; 2019 , Pages 322-325 ; 9781728101279 (ISBN) ; Zohoor, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
In this paper, acoustic energy harvesting using a tunable Helmholtz Resonator (HR) is investigated. The frequency of resonator can be changed by varying the radial force in a membrane which is used in one of its face. Applying acoustic pressure, vibrates the air inside HR neck and therefore changes pressure in HR chamber which results in membrane vibration. Attached magnet to the membrane will vibrate and its relative motion to a fixed coil generates voltage on the basis of Faraday's law of induction. Modeling approach is developed considering equivalent nonlinear membrane stiffness and coupling of electrical circuit and mechanical device. At the end, system behavior is studied numerically...
Multiphysics modeling of an MSMA-based clamped-clamped inertial energy harvester
, Article Smart Materials and Structures ; Volume 28, Issue 3 , 2019 ; 09641726 (ISSN) ; Zakerzadeh, M. R ; Sharif University of Technology
Institute of Physics Publishing
2019
Abstract
In this paper, an alternative way of harvesting energy from ambient vibration is investigated through proposing a novel inertial energy harvester using magnetic shape memory alloys (MSMAs). To this end, a clamped-clamped beam is coupled with MSMA units which are attached to its roots. A shock load is applied to a proof mass in the middle of the beam. The beam vibration causes longitudinal strain in the MSMAs and as a result the magnetic flux alters in the coils wounding around the MSMA units and produce an AC voltage. To have a reversible strain in MSMAs, a bias magnetic field is applied in transverse direction of the MSMA units. The large scale vibration of Euler-Bernoulli beam is modeled...
Energy harvesting via shallow cylindrical and spherical piezoelectric panels using higher order shear deformation theory
, Article Composite Structures ; Volume 147 , 2016 , Pages 155-167 ; 02638223 (ISSN) ; Rahnama, F ; Askari Farsangi, M. A ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
In this article an analytical solution is presented for power output from a piezoelectric shallow shell energy harvester using higher order shear deformation theory (HSDT). The energy harvester is made of an elastic substrate layer coupled with one or two surface bonded piezoelectric layers. Mechanical equations of motion with Gauss's equation are derived on the basis of HSDT and solved simultaneously for simply-supported mechanical boundary conditions. The electromechanical frequency response functions that relate the power output and circuit load resistance are identified from the exact solutions. Using Rayleigh damping the influence of structural damping is taken into account. Also...
A novel inertial energy harvester using magnetic shape memory alloy
, Article Smart Materials and Structures ; Volume 25, Issue 10 , 2016 ; 09641726 (ISSN) ; Sayyaadi, H ; Zakerzadeh, M. R ; Sharif University of Technology
Institute of Physics Publishing
2016
Abstract
This paper studies the output voltage from a novel inertial energy harvester using magnetic shape memory alloys (MSMAs). The MSMA elements are attached to the root of a cantilever beam by means of two steps. In order to get electrical voltage, two coils are wound around the MSMAs and a shock load is applied to a tip mass at the end of the beam to have vibration in it. The beam vibration causes strain in the MSMAs along their longitudinal directions and as a result the magnetic flux alters in the coils. The change of magnetic flux in the surrounding coil produces an AC voltage. In order to predict the output voltage, the nonlinear governing equations of beam motion based on Euler-Bernoulli...
Modeling and parametric studies of magnetic shape memory alloy–based energy harvester
, Article Journal of Intelligent Material Systems and Structures ; Volume 29, Issue 4 , 2018 , Pages 563-573 ; 1045389X (ISSN) ; Rostami Najafabadi, H ; Askari Farsangi, M. A ; Sharif University of Technology
SAGE Publications Ltd
2018
Abstract
This article presents a model to simulate the behavior of a magnetic shape memory alloy while harvesting vibratory energy. In this type of energy harvester, magnetic shape memory alloy element is placed in the air gap of a ferromagnetic core which conducts the magnetic flux. Two apparent coils are wound around a ferromagnetic core: one to produce bias magnetic field by passing a rectified electric current and the other to serve as an energy pickup coil. Applying compressive time-variant strain field to magnetic shape memory alloy element changes its dimensions and magnetic properties as well. Presence of the bias magnetic field returns magnetic shape memory alloy element to its initial state...
Dithiocarbamate as an efficient intermediate for the synthesis of 2-(alkylthio)thiazol-4(5H)-ones
, Article Journal of Sulfur Chemistry ; Volume 37, Issue 5 , 2016 , Pages 529-536 ; 17415993 (ISSN) ; Alaei, M. A ; Soleymani Movahed, F ; Jomeh, N ; Saidi, M. R ; Sharif University of Technology
Taylor and Francis Ltd
2016
Abstract
An effective approach for the synthesis of 2-(alkylthio)thiazol-4(5H)-ones from alkyl dithiocarbamates and chloroacetyl chloride in the presence of NaHCO3 has been developed. Good to excellent yields of products, simple reaction conditions and general applicability are the most important advantages of this protocol
Modeling, Analysis and Experimental Investigation of Energy Harvesting via Magnetic Shape Memory Alloys
, Ph.D. Dissertation Sharif University of Technology ; Sayyadi, Hassan (Supervisor) ; Zakerzadeh, Mohammad Reza (Co-Advisor)
Abstract
Vibration based energy harvesting is the process of trapping and collecting vibrational energy from ambient sources which seem unusable at first sight. The smart materials with the capability of coupling two different fields can be used in converting vibrational energy to electrical one. One of this smart material which has been taken into account recently is the Magnetic Shape Memory Alloy (MSMA) and it can couple the magnetic and mechanical fields. In MSMAs the total magnetization vector changes with the application of stress and make it possible to harvest energy from Faraday law’s of induction. An important phenomena that exist in MSMA is the dependency of magnetization-strain behavior...
Energy harvesting from structural vibrations of magnetic shape memory alloys
, Article Applied Physics Letters ; Volume 110, Issue 10 , 2017 ; 00036951 (ISSN) ; Cottone, F ; Sayyaadi, H ; Zakerzadeh, M. R ; Orfei, F ; Gammaitoni, L ; Sharif University of Technology
American Institute of Physics Inc
2017
Abstract
This letter presents the idea of scavenging energy from vibrating structures through magnetic shape memory alloy (MSMA). To this end, a MSMA specimen made of Ni50Mn28Ga22 is coupled to a cantilever beam through a step. Two permanent magnets installed at the top and bottom of the beam create a bias field perpendicular to the magnetization axis of the specimen. When vibrating the device, a longitudinal axial load applies on the MSMA, which in turn changes the magnetization, due to the martensitic variant reorientation mechanism. A pick-up coil wounded around the MSMA converts this variation into voltage according to the Faraday's law. Experimental test confirms the possibility of generating...
Cancer Detection and Classification in Histopathology Images Under Small Training Set
, M.Sc. Thesis Sharif University of Technology ; Rohban, Mohammad Hossein (Supervisor) ; Sharifi Zarchi, Ali (Supervisor)
Abstract
Histopathology images are a type of medical images that are used to diagnose a variety of diseases. One of these illnesses is the Leukemia cancer, which has four different subtypes and is diagnosed using a blood smear image. As a result of the advancement of deep learning tools, models for diagnosing various types of disease from images have been developed in recent years.In this project, one of the best models developed to diagnose four different types of disease was replicated, and it was demonstrated that, while this model achieves acceptable accuracy, its decision is not based on medically significant criteria. In the following, a general method for diagnosing the disease is proposed...