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Aerodynamic Design of 100 kW Transonic Ducted Fan
, M.Sc. Thesis Sharif University of Technology ; Ghorbanian, Kaveh (Supervisor)
Abstract
The purpose of this research is the aerodynamic design of a 100 kW transonic ducted fan. Today, the aviation industry is moving towards the design of electric driven aircraft propulsion. Transonic ducted fans are one of the viable options that have been used in medium and heavy aircrafts due to their high specific power. In this research, the meanline model has been used for the initial design. By applying the design constraints, design limitations, design and functional parameters, the initial design point is found and then a sensitivity analysis is performed with respect to the effective design parameters to obtain the optimal design point. For the initial design of the transonic ducted...
Techno-Economic Comparison of Different Gas Turbine Inlet Cooling Techniques
, M.Sc. Thesis Sharif University of Technology ; Hakkaki Fard, Ali (Supervisor)
Abstract
Inlet air cooling is a simple and economical method to increase the power output of gas turbines. High-pressure fogging systems and mechanical chillers are two common methods. High water consumption, damage to compressor blades by water droplets, and inefficiency in humid climates are disadvantages of high-pressure fogging systems. Mechanical chillers have high electricity consumption and initial costs. In this research, an earth-to-air heat exchanger (EAHE) is introduced as a new method for inlet air cooling of gas turbines and is technically and economically compared with the two common methods in the long term in the climate of Tehran city. Temperature distribution in the ground is...
Authentication phase of security bootstrapping in the internet of things networks based on a trusted zone
, Article Journal of Scientific and Industrial Research ; Volume 78, Issue 11 , 2019 , Pages 751-754 ; 00224456 (ISSN) ; Manzuri, M. T ; Sharif University of Technology
Scientific Publishers
2019
Abstract
Internet of Things (IoT) represents enabling all things in such a smart way that those things be accessed any time and anywhere through the Internet. Presence of IoT as a novel way of networking, opens up new concernsaround the communication and network world. A secure establishing in such a diffused network is a great concerns of the researchers. Due to Smart things' resource-constraints and power-limitation the former ways of securing networks cannot be applicable in IoT. Thus, security bootstrapping has introduced a solution for establishing security in the first instance of deploying the network. In this study, we have proposed a security bootstrapping solution which can be applied in...
The Effects of Non-Gaussian Operations in Increasing the Secure Length of Quantum Communications based on Continuous Variables
, M.Sc. Thesis Sharif University of Technology ; Bahrampour, Alireza (Supervisor)
Abstract
Quantum key distribution (QKD), as one of the applications in quantum information processing, allows two distant legitimate parties to establish a set of secure keys even in the presence of an untrusted environment controlled by an eavesdropper. In general, QKD mainly includes two families, namely, discrete variable quantum key distribution (DV-QKD) and continuous variable quantum key distribution (CV-QKD). In CV-QKD system, the sender Alice, encodes information on the quadratures of the optical field with Gaussian modulation, and the receiver Bob, decodes the secret information with homodyne or heterodyne detection so that this system promises a higher secret key rate than its DV-QKD...
Improvement of robot navigation using fuzzy method
, Article 2013 3rd Joint Conference of AI and Robotics and 5th RoboCup Iran Open International Symposium: Learning, Glorious Future ; 2013 , pp.1-5 ; 9781467363150 (ISBN) ; Amiryan, J ; Nazemi, E ; Sharif University of Technology
2013
Abstract
In this paper a technique for autonomous navigation of mobile robots is presented. The most important advantage of this method is to ignore the physical model of the robot and that the robot model is considered as an unknown but predictable system. This approach can be executed in environments which robot navigation is done using global sensors e.g. a camera installed in the environment to sense and control the robot and also every feedback system which is able to measure the velocity of the robot can be used for this technique. In this approach, the well-known fuzzy method, Takagi-Sugeno, has been applied to estimate the dynamic model of robot. Our technique has been applied successfully in...
Design and Optimization of Carbon Capture System from Exhaust Gases in the Process Industries
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor) ; Seif, Shayan (Co-Supervisor)
Abstract
Carbon dioxide is one of the main geenhouse gases emitted from factories as well as transportation vehicles that adversely affect the atmosphere and cause global warming. Among the proposed solutions to reduce carbon dioxide in the atmosphere, carbon dioxide separation would be the most viable medium-term approach. However, the high cost of carbon dioxide separation prevents the development of carbon dioxide absorption technologies. Therefore, it seems that integrating separation and production processes is the most efficient way to save energy and reduce carbon emissions. This method decrease a high proportion of the energy consumption in upstream operations (carbon dioxide removal,...
Simulation and Evaluation of the Security Sub-Layer for IoT
, M.Sc. Thesis Sharif University of Technology ; Manzuri Shalmani, Mohammad Taghi (Supervisor)
Abstract
Internet of Things means making the all of things smart to access them anytime, anywhere through the Internet. Existing of IoT as a novel way of networking, opens up new issues round the communication and network world. One of them is how to establish the security in such a diffuse network. Because the members of this network are not smart phones, computers or any other usual networking technologies, but they are the normal things and appliances in our daily lives, such as refrigerators. Smart things are mostly resource-constrained and power-limited so the former ways of securing networks cannot be applicable in IoT. Thus, Security bootstrapping has is introduced a solution for establishing...
The Impact of Environmental Pollutants on Housing Valuation in Iranian Metropolises
, M.Sc. Thesis Sharif University of Technology ; Keshavarz Haddad, Gholamreza (Supervisor)
Abstract
In this study, we intend to investigate the effect of pollution levels on the valuation of residential units in Tehran. The method used in this research is Hadanik pricing method. Data required for the project, in relation to the intrinsic characteristics of housing including number of bedrooms, building life, area and… air pollution index by regional stations on a daily basis and housing environmental characteristics including per capita green space, day and night pollution index, density The population of the area and… are collected. According to the results, they have the greatest impact on determining the value of the building area and building life, and after controlling for other...
Failure analysis of bolted joints in foam-core sandwich composites
, Article Journal of Reinforced Plastics and Composites ; Volume 27, Issue 15 , 2008 , Pages 1635-1647 ; 07316844 (ISSN) ; Moslemian, R ; Afshin, M ; Nazemi, M. H ; Sharif University of Technology
2008
Abstract
This study represents an effort to predict the bearing strength, failure modes, and failure load of bolted joints in foam-core sandwich composites. The studied joints have been used in a light full composite airplane. By using solid laminates, a new design for the joint zone is developed. These solid laminates include a number of glass plies with total thickness equal to core thickness. The effect of solid laminate size and interface angle of foam-solid laminate in the bonding zone on the bearing strength, failure loads and type of modes are investigated. The numerical study is performed using 3D FEM in ANSYS commercial code. Tsai-Wu failure criterion is used in the failure analysis. The...
Energy storage planning for enhanced resilience of power distribution networks against earthquakes
, Article IEEE Transactions on Sustainable Energy ; Volume 11, Issue 2 , 2020 , Pages 795-806 ; Moeini Aghtaie, M ; Fotuhi Firuzabad, M ; Dehghanian, P ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
Energy infrastructures are perceived continuously vulnerable to a range of high-impact low-probability (HILP) incidents - e.g., earthquakes, tsunamis, floods, windstorms, etc. - the resilience to which is highly on demand. Specifically suited to battery energy storage system (BESS) solutions, this paper presents a new resilience-driven framework for hardening power distribution systems against earthquakes. The concept of fragility curve is applied to characterize an earthquake hazard, assess its impact on power distribution systems, and estimate the unavailability of the network elements when exposed to extreme earthquakes. A new metric is defined to quantify the network resilience taking...
The knowledge map of energy security
, Article Energy Reports ; Volume 7 , 2021 , Pages 3570-3589 ; 23524847 (ISSN) ; Bagheri Moghaddam, N ; Maleki, A ; Nazemi, A ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Much efforts have been made in the area of energy security in recent years, but due to its wide scope, it is necessary to review relevant knowledge activities and to analyze the state of knowledge of the field of energy security measurement. The purpose of this article is to present a comprehensive map of knowledge in the field of energy security. For this reason, many documents and articles have been collected during the period 2002–2019 using 7 large and reputable scientific databases as well as 53 different journals, 90% white Q1 quality. There is employed meta-synthesis, scientometrics and network analysis. In the initial survey stage where 1290 articles were found, after analyzing the...
Design and Optimization of a 10 kW Dish/Stirling System
,
M.Sc. Thesis
Sharif University of Technology
;
Boroushaki, Mehrdad
(Supervisor)
;
Rajabi Qahnuyeh, Abbas
(Supervisor)
Abstract
Nowadays, electricity generation technology from renewable resources, especially solar energy has been very popular; specifically off-grid systems which have the ability of decentralized electricity generation. Dish/Stirling system is one of the most efficient technologies with capability of decentralized electricity generation from solar energy. The purpose of this study is design, optimization and analysis of a 10 KW Dish/Stirling system for different working location in Iran.
A mathematical model is introduced to analyze all the heat losses in different system components including parabolic dish, cavity receiver and Stirling engine. All the calculations are done with MATLABTM...
A mathematical model is introduced to analyze all the heat losses in different system components including parabolic dish, cavity receiver and Stirling engine. All the calculations are done with MATLABTM...
Financial Market Forecasting Using Deep Graph Neural Networks
, M.Sc. Thesis Sharif University of Technology ; Soleymani Baghshah, Mahdieh (Supervisor) ; Beigy, Hamid (Supervisor)
Abstract
Forecasting and analysing financial markets has always been an interesting research topic for fields ranging from financial sciences to mathematics and statistics. With the rapid development of artificial intelligence in the recent years, there has been a growing interest in using deep neural networks to predict market future trends. The price in these markets is determined by mechanisms of demand and supply. When there is a tendancy to buy a stock, there will be an increase in demand resulting a positive growth for price. On the other hand, when a large group of investors decide to sell their assets, market will experience an increase in supply and subsequently the prices drop. Availability...
Effect of Initial Surface Roughness on the Residual Stress Profile Induced by Shot Peening Process using Finite Element Method and Machine Learning Algorithms
, M.Sc. Thesis Sharif University of Technology ; Farrahi, Gholamhossein (Supervisor) ; Chamani, Mohammad (Co-Supervisor)
Abstract
Shot peening process, which induces compressive residual stress near the surface, is one of the most effective methods for enhancing surface properties. Shot peening on smooth surfaces increases surface roughness, which is a factor that can reduce fatigue life. Conversely, the distribution of compressive residual stress contributes to improved fatigue life. Therefore, examining the initial surface conditions and the effects of average surface roughness on residual stress distribution is essential.In this study, due to the limited attention given to initial surface roughness in previous research, a finite element model of the shot peening process was developed considering the actual...
Preparation of Polycarbonate Membrane for Industrial Wastewater Treatment in Membrane Bioreator
, M.Sc. Thesis Sharif University of Technology ; Mousavi, Abbas (Supervisor) ; Bastani, Dariush (Supervisor)
Abstract
Today, membrane bioreactors (MBRs) process is one of the most important options in industrial and municipal wastewater treatment. In MBRs, membrane has an essential influence on their performance. In this study, polycarbonate was exploited as membrane to evaluate its performance in MBR since it has excellent mechanical properties. However, polycarbonate is brittle and breaks at low elongation at room temperature. Solution blending was utilized to improve polycarbonate’s properties. Blending membrane was characterized and assessed by scanning electron microscopy (SEM) and tensile strength. Polycarbonate solution blending with polyurehatne which has excellent toughness and flexibility enhance...
Planning Studies of Energy Storage Systems in Distribution Network with the Main Goal of Improving the System’s Resilience
, M.Sc. Thesis Sharif University of Technology ; Fotuhi Firuzabad, Mahmoud (Supervisor) ; Rajabi Ghahnavieh, Abbas (Supervisor)
Abstract
Occurrence of natural disasters such as flood, windstorms, tsunamis and earthquakes has caused striking effects on critical infrastructures like power systems in recent decades. There are some examples of high-impact low-possibility (HILP) events which causes catastrophic effects on power systems. Traditionally, planning and operational studies of power system have been run taking into account some reliability metrics. Although, the reliability indices can represent the ability of a system in confronting with possible failures of components, they are unable to efficiently consider the effects of severe events such as earthquake and other HILP events. Moreover, traditional power systems were...
Effect of anterior cruciate ligament injury on acceleration response of knee joint
, Article Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine ; Volume 238, Issue 5 , 2024 , Pages 488-499 ; 09544119 (ISSN) ; Hosseini Lorgan, S. H ; Sherafat Vaziri, A ; Tahmasebi, M. N ; Shayan Moghadam, R ; Farahmand, F ; Sharif University of Technology
2024
Abstract
This study investigated the effect of anterior cruciate ligament (ACL) injury on relative acceleration of the tibia and femur during a number of tests/activities, in order to assess the feasibility of acceleration-based diagnosis of ACL injury using inertial sensors. First, a detailed finite element model of the knee joint was developed to simulate the target tests/activities, and identify those in which a large difference between the maximum acceleration peaks (MAPs) of the healthy and ACL injured knees is likely to be observed. The promising tests/activities were entered in an experimental study, where the relative accelerations of the tibiae and femurs of 20 individuals with unilateral...
Designing an Emotion Capturing System Using Eeg Signals and Human-obot Interaction Platform Based on the Captured Emotion
, M.Sc. Thesis Sharif University of Technology ; Taheri, Alireza (Supervisor) ; Meghdari, Ali (Supervisor) ; Ghazizadeh, Ali (Co-Supervisor)
Abstract
Emotions are one of the most important issues which affects daily life and activities. On the other hand, robots play an increasing role in human life and play a fundamental role in meeting our needs. One of these basic roles is empathy and verbal interaction between the robot and human. In this research, participant's emotions were stimulated in two ways: by using OASIS and GAPED image data sets and by instructing the participants to remind about their good or bad memories. During emotional stimulation, EEG signals have been recorded for the training and testing process. The preprocessing of training data includes filtering, removing bad parts of data, removing bad channels and...