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babaee--mohammad
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Nonlinear Dynamic Analysis of Earth and Rockfill Dams Using the Finite Difference Method Considering the Effect of Vertical Earthquake Component
, M.Sc. Thesis Sharif University of Technology ; Haeri, Mohsen (Supervisor)
Abstract
Earth and rockfill dams are enormous three-dimensional structures constructed from earth and rockfill materials. They are mainly built for water supply, agricultural land irrigation, electricity generation, and flood control. Earthquake is one of the most significant natural hazards affecting the stability of these dams. Nowadays, with the development of computers and software, the seismic behavior of most dams are assessed by dynamic analysis. In a considerable part of technical literature, dynamic analysis of earth and rockfill dams have been performed by applying only the horizontal component of the earthquakes, and the effects of vertical component of the earthquakes have often been...
Design and Implementation of a DC/AC Converter with High Step up and High Efficiency in Wide Output Power Range for Photovoltaic Applications
, M.Sc. Thesis Sharif University of Technology ; Zolghardi, Mohammad Reza (Supervisor)
Abstract
Solar power is expensive, so engineers are encouraged to put effort on increasing efficiency of solar power equipments. Since photovoltaic panels usually output a low voltage, variable direct current electricity, a boost converter and a suitable inverter are required to use this energy for ordinary commercial appliances. In this project, high step up, high efficiency converters are investigated, and the best converter with high efficiency and limited switch stress which achieves high voltage gain by capacitor multipliers and coupled inductors is illustrated. Afterwards, methods for improving efficiency such as modifying the converter structure and its control strategy are suggested. The...
Nonlinear Analysis of Vibration of Tapered Piezo Electromagnetic Beam in Presence of External Permanent Magnet in Order to Energy Harvesting Improvement
, M.Sc. Thesis Sharif University of Technology ; Hosseini Kordkheili, Ali (Supervisor)
Abstract
With the increasing development in the field of electronics and information technology, the required dimensions and power of electronic devices and sensors have decreased. The range of applications of these electronic devices is very large, which is the product of technological progress development. There is a problem in the development and application of such devices, the supply of electrical power used in them, especially in the set of wireless sensors, this problem is more significant.The use of piezoelectric materials is one of the methods of converting mechanical energy into electrical energy. The voltage generated by the piezoelectric material can be used to charge the capacitor or...
Control of a Group of Mobile Manipulators for Cooperative object Transportation
, M.Sc. Thesis Sharif University of Technology ; Sayyadi, Hassan (Supervisor)
Abstract
In this thesis control of wheeled mobile manipulators for cooperative object transportation is investigated. Full dynamic model of a mobile manipulator with a three wheeled mobile base and a three DOF manipulator is derived using Gibbs-Appell method. Input-output linearization technique is used to control individual robots. Transporting the object is divided into two steps, first robots use a decentralized behavior-based method to approach and surround the object. Then virtual structure method is used to control the robots to transport the object cooperatively. Simulation results with three robots handling an object are presented to show the effectiveness of proposed method
Anaerobic digestion of vegetable waste
, Article Chemical Engineering Transactions ; Volume 24 , 2011 , Pages 1291-1296 ; 19749791 (ISSN) ; Shayegan, J ; Sharif University of Technology
Italian Association of Chemical Engineering - AIDIC
2011
Abstract
Fruit and vegetable wastes are produced in large quantities in Iran, and constitute a source of nuisance in municipal landfills. The objective of this study was to optimize the applications of anaerobic digestion for the treatment of municipal organic wastes. We studied the effect of organic loading rates on anaerobic digestion of vegetable wastes. The complete-mix, pilot-scale digester with working volume of 70 1 was used. The experiments were conducted at 34°C with a fixed hydraulic retention time of 25 days. The digester was operated at different organic feeding rates of 1.4, 2 and 2.75 kg VS/(m3.d). The biogas produced had methane composition of 49.7- 64% and biogas production rates of...
Four suggested plans of underwater Robo-snake
, Article World Academy of Science, Engineering and Technology ; Volume 38 , 2009 , Pages 1094-1099 ; 2010376X (ISSN) ; Sharifazadeh, H ; Sharif University of Technology
2009
Abstract
Throughout this paper four locomotion mechanisms have been presented for underwater robo-sankes. In this respect; initially, two methods of locomotion including traveling and standing wave have been examined. Next, applications of these methods are described. Ultimately, assessing and comparison of those mechanisms have been studied and the best plan is determined. © 2009 WASET.ORG
Design of Anaerobic Digestion for Solid Waste Treatment
, M.Sc. Thesis Sharif University of Technology ; Shayegan, Jalaleddin (Supervisor)
Abstract
In this project, performance of anaerobic digestion of organic waste in liquid phase has been investigated in an experimental process. Thus, the objective of this study was to optimize the organic loading rates, temperature and mixing of anaerobic digestion to the treatment of municipal solid wastes. To achieve this, the pilot scale experiment was conducted in 70l, fully mixed reactor. The start-up process was established over a period of 2 months. Starting the digestion in two stages was done with two different feed stocks, in which the feed stock of the first stage was star and in the second stage vegetables were considered as the organic waste. Experiment was investigated in mesophilic...
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...
Methane production from anaerobic co-digestion of poultry manure
, Article Journal of Environmental Studies ; Volume 38, Issue 62 , Sep , 2012 , Pages 83-88 ; 10258620 (ISSN) ; Shayegan, J ; Babaee, A ; Sharif University of Technology
2012
Abstract
According to the results, anaerobic co-digester appeared to be feasible with the loading rate of 3.0 kg VS/ m 3.d at 34°C and biogas production rate of 44.8 1/d, which can be used as a fuel resource. It should be mentioned that more heat input is required to achieve the correct operational temperature. This increase in energy may not be outweighed by the increase in the outputs of biogas from the system. Therefore, it is important to consider an energy balance for these systems
State, institutional entrepreneurship and the creation of the biopharmaceutical industry in a developing country
, Article Journal of Science and Technology Policy Management ; 2021 ; 20534620 (ISSN) ; Mashayekhi, A. N ; HamidiMotlagh, R ; Sharif University of Technology
Emerald Group Holdings Ltd
2021
Abstract
Purpose: This study aims to explore the emergence and development of new industries, especially in the context of developing countries, by considering industry emergence and development as a large-scale institutional change or transition. Design/methodology/approach: The authors conducted an inductive case study research on the emergence of the biopharmaceutical industry in a developing country. The data on the emergence and development of Iran’s biopharmaceutical industry during 1990 and 2018 were collected through semi-structured interviews, participation in meetings, visits to companies and analysis of archival texts. The data analysis was an inductive and iterative process. Findings: In...
State, institutional entrepreneurship and the creation of the biopharmaceutical industry in a developing country
, Article Journal of Science and Technology Policy Management ; Volume 13, Issue 4 , 2022 , Pages 765-787 ; 20534620 (ISSN) ; Mashayekhi, A. N ; HamidiMotlagh, R ; Sharif University of Technology
Emerald Publishing
2022
Abstract
Purpose: This study aims to explore the emergence and development of new industries, especially in the context of developing countries, by considering industry emergence and development as a large-scale institutional change or transition. Design/methodology/approach: The authors conducted an inductive case study research on the emergence of the biopharmaceutical industry in a developing country. The data on the emergence and development of Iran’s biopharmaceutical industry during 1990 and 2018 were collected through semi-structured interviews, participation in meetings, visits to companies and analysis of archival texts. The data analysis was an inductive and iterative process. Findings: In...
Spin FET based on graphene nanoribbon in the presence of surface roughness
, Article IEEE Transactions on Electron Devices ; Volume 64, Issue 8 , 2017 , Pages 3437-3442 ; 00189383 (ISSN) ; Faez, R ; Babaee Touski, S ; Pourfath, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
In this paper, the characteristics of an armchair graphene nanoribbon spin FET (SFET) are investigated in the presence and absence of surface roughness, by employing a multiorbital tight-binding method along with the nonequilibrium Green's function approach. It is found that the bandgap monotonically decreases with increasing the vertical electric field, since Stark effect enhances spin-flip rate under a high vertical electric field. Furthermore, spin transport in the presence of a random potential, which is induced by the concurrent effect of the applied vertical electric field and surface roughness, is carefully analyzed. This random potential strongly scatters carriers and reduces spin...
Validation of the Saadat NIBP module according to the ANSI/AAMI-SP10 protocol
, Article 2013 20th Iranian Conference on Biomedical Engineering, ICBME 2013 ; Deembec , 2013 , Pages 199-202 ; Mashayekhi, G ; Behzadfar, N ; Yaghoobzadeh, A ; Babaee, T ; Sharif University of Technology
IEEE Computer Society
2013
Abstract
This study is conducted with the aim of validating the Saadat non-invasive blood pressure (NIBP) module accuracy and reliability against direct intra arterial pressure measurement (IBP) according to the ANSI/AAMI SP10-2002 guidelines. Measurement and comparison procedure were done in a static population of 19 adult patients with brachial catheterized arterial line with total measurements of 195 under supervision of a highly experienced cardiovascular anesthesiologist in accordance with the ANSI/AAMI SP10-2002 regulation. Data analysis was performed based on the protocol criteria. In order to represent relationships between the test device and the reference method, Bland-Altman graphical...
Efficiency improvement of a high step up high efficiency converter for photovoltaic applications based on three-state switching cell
, Article PEDSTC 2013 - 4th Annual International Power Electronics, Drive Systems and Technologies Conference ; 2013 , Pages 454-458 ; 9781467344845 (ISBN) ; Zolghadri, M. R ; Hajimoradi, M. R ; Sharif University of Technology
2013
Abstract
This paper suggests methods for improving efficiency of a high step up high efficiency converter based on three state commutation cells. A loss analysis has been performed to identify the source of power loss. Based on this analysis, methods are presented to reduce losses in the most power dissipating elements. These methods include replacing some power diodes with large conduction losses with MOSFETs having small on-state resistance. Efficiency improvement up to %1.25 percent is verified in simulation and experimental results
Performance evaluation of Omni-Channel distribution network configurations considering green and transparent criteria under uncertainty
, Article Sustainability (Switzerland) ; Volume 14, Issue 19 , 2022 ; 20711050 (ISSN) ; Khedmati, M ; Akbari Jokar, M. R ; Babaee Tirkolaee, E ; Sharif University of Technology
MDPI
2022
Abstract
Satisfying customer demand is one of the growing concerns of supply chain managers. On the other hand, the development of internet communications has increased online demand. In addition, the COVID-19 pandemic has increased the demand for online shopping. One of the useful concepts that help to address this concern is the omni-channel strategy, which integrates online and traditional channels with the aim of improving customer service level. For this purpose, this paper proposes an algorithm for evaluating Omni-channel Distribution Network Configurations (OCDNCs). The algorithm applies an extended Data Envelopment Analysis (DEA) model to evaluate OCDNCs based on cost, service, transparency,...
Comparing two orthoses for managing medial knee osteoarthritis: lateral wedge with subtalar strap while barefoot versus lateral wedged insole fitted within sandal
, Article Indian Journal of Orthopaedics ; 2021 ; 00195413 (ISSN) ; Jalali, M ; Babaee, T ; Safaeepour, Z ; Torkaman, A ; Baniasad, M ; Sharif University of Technology
Springer
2021
Abstract
Background: Using foot orthoses for managing medial knee osteoarthritis (MKOA) is common, although its effectiveness is in debate. Most orthoses are placed inside the shoe as a lateral wedged insole. Thus, most studies in this area have focused on the effect of insoles used with shoes. This study compared the effects of a lateral wedge with subtalar strap (combined insole) used while barefoot and lateral wedged insole fitted within sandal on pain, function and external knee adduction moment (EKAM) in patients with MKOA to consider which orthotic treatment is better. Methods: In this quasi-experimental pretest–posttest study, 29 participants with medial knee osteoarthritis were divided into...
Comparing Two orthoses for managing medial knee osteoarthritis: lateral wedge with subtalar strap while barefoot versus lateral wedged insole fitted within sandal
, Article Indian Journal of Orthopaedics ; Volume 56, Issue 2 , 2022 , Pages 319-326 ; 00195413 (ISSN) ; Jalali, M ; Babaee, T ; Safaeepour, Z ; Torkaman, A ; Baniasad, M ; Sharif University of Technology
Springer
2022
Abstract
Background: Using foot orthoses for managing medial knee osteoarthritis (MKOA) is common, although its effectiveness is in debate. Most orthoses are placed inside the shoe as a lateral wedged insole. Thus, most studies in this area have focused on the effect of insoles used with shoes. This study compared the effects of a lateral wedge with subtalar strap (combined insole) used while barefoot and lateral wedged insole fitted within sandal on pain, function and external knee adduction moment (EKAM) in patients with MKOA to consider which orthotic treatment is better. Methods: In this quasi-experimental pretest–posttest study, 29 participants with medial knee osteoarthritis were divided into...
Construction of an Experimental Device for Foaming Agent and an Experimental Study of the Properties of Foaming Agent
, M.Sc. Thesis Sharif University of Technology ; Bazargan, Mohammad (Supervisor)
Abstract
The primary purpose of acidizing operations in the oil and gas industry is to enhance hydrocarbon production. Acidizing has been a common and conventional method for years, especially when production engineers face issues like declining reservoir pressure leading to reduced production rates. Initially, the treatment solution is referred to as matrix acidizing. In acidizing operations, different additives are combined with the acid to control its behavior in the reservoir. These additives may include iron control agents, corrosion inhibitors, friction reducers, and more. Incompatibility among these additives, the acid, and reservoir fluids can lead to severe damage to the reservoir....
Numerical Analysis of An Annular Gas Turbine Combustor
, M.Sc. Thesis Sharif University of Technology ; Farshchi, Mohammad (Supervisor)
Abstract
The goal of this research is the simulation of the annular combustion chamber of the turbine engine utilized by liquid fuel. The achievement to this goal will lead to create numerical tools for parametric study, analysis and combustion chamber designing.For this reason simple geometry has been considered. This simplicity of geometry causes to facilitate in parametric study and decrease in saving time for modeling and meshing. This combustion chamber is a simplified model of engine CF6. In recent study, the k – ε realizable model has been used for turbulence modeling. For non-adiabatic condition, chemical reaction is dissolved by utilizing probability density function along with laminar...
A misbehavior‐tolerant multipath routing protocol for wireless Ad hoc networks [electronic resource]
, Article International Journal of Research in Wireless Systems (IJRWS) ; Vol. 2, Issue 9, pp. , Sep. 2013 ; Pakravan, Mohammad Reza ; Aref, Mohammad Reza ; Sharif University of Technology
Abstract
Secure routing is a major key to service maintenance in ad hoc networks. Ad hoc nature exposes the network to several types of node misbehavior or attacks. As a result of the resource limitations in such networks nodes may have a tendency to behave selfishly. Selfish behavior can have drastic impacts on network performance. We have proposed a Misbehavior-Tolerant Multipath Routing protocol (MTMR) which detects and punishes all types of misbehavior such as selfish behavior, wormhole, sinkhole and grey-hole attacks. The protocol utilizes a proactive approach to enforce cooperation. In addition, it uses a novel data redirection method to mitigate the impact of node misbehavior on network...