Investigation into the Effect of Material and Geometrical Parameters on Mechanical Behavior of Medical Guidewire

, M.Sc. Thesis Sharif University of Technology Heidary, Mahdi (Author) ; Arghavani Hadi, Jamal (Supervisor)

Abstract

Today, tens of millions of people on the planet suffer from heart disease. For the correct diagnosis and treatment of these diseases, there is a vital need for accurate scientific evidence such as various types of vascular and cardiac imaging. One of the applications of guidewires is in cardiovascular imaging. Of course, in addition to diagnosis, this device is also used in the treatment of disease. It should be noted that about 21 million central vessel catheters are performed annually on heart patients, of which about 16 million are performed using the seldinger method. Reportedly, unfortunately, 5% to 19% of these operations have had side effects and harm to the patient or failure....

The Implementation of an Operational MODIS Aerosol Retrieval Algorithm at High Spatial Resolution

, M.Sc. Thesis Sharif University of Technology Heidary, Parisa (Author) ; Tajrishy, Masoud (Supervisor)

Abstract

Urmia Lake is one of the largest permanent hypersaline lakes in the world. Since Urmia Lake is faced with drying phenomena, the release of dust from its surface is expected. The most appropriate technique on dust storms is the remote sensing technique. One of the most popular parameter that provides the integrated information over a vertical column of unit cross section of this phenomenon is aerosol optical depth (AOD). Satellite remote sensing has been used to retrieve AOD over land and ocean at spatial resolutions of several to several tens of km. However, higher spatial resolution aerosol products for local scale areas have not been well-researched mainly due to the difficulty of...

Vole Population Dynamics Under the Influence of Specialist and Generalist Predation

, M.Sc. Thesis Sharif University of Technology Heidary, Samira (Author) ; Hesaraki, Mahmud (Supervisor)

Abstract

To understand the impact of predation by different types of predators on the vole population dynamics,we formulate a three differential equation model describing the population dynamics of voles, the “specialist predator”and the “generalist predator.” First we perform a local stability study of the different steady states of the basic model and deduce that the predation rates of the “specialist” as well as the “generalist” predator are the main parameters controlling the existence/extinction criteria of the concerned populations. Next we analyze the model from a thermodynamic perspective and study the thermodynamic stability of the different equilibria. The analysis revealsthat when the...

Control of thermo magnetic heat transfer in porous cavity with Baffle(s)

, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings, 13 November 2009 through 19 November 2009 ; Volume 9, Issue PART A , 2010 , Pages 627-631 ; 9780791843826 (ISBN) Heidary, H ; Davoudi, M ; Pirmohammadi, M ; Sharif University of Technology

2010

Abstract

Steady, laminar, natural-convection flow in the presence of a magnetic field in a porous cavity heated from left wall sinusoidally and cooled from right wall is considered. It is well known that unavoidable hydrodynamic movements can be damped with the help of a magnetic field. The Finite Volume method and SIMPLE algorithm for discretizing is used to solve the non-dimensional governing equations. The Convection and Diffusion term of the equations are discretized by Central Difference Scheme (CDS).The numerical procedure has been done over a range of Rayleigh number, Ra, and value of Hartmann number (Ha), 0 ≤ Ha ≤ 150 and effect of them is investigated on average and local Nusselt number....

Feasibility study on application of the recent enhanced heavy oil recovery methods (VAPEX, SAGD, CAGD and THAI) in an iranian heavy oil reservoir

, Article Petroleum Science and Technology ; Volume 35, Issue 21 , 2017 , Pages 2059-2065 ; 10916466 (ISSN) Heidary, S ; Dehghan, A. A ; Mahdavi, S ; Sharif University of Technology

2017

Abstract

Enhanced oil recovery (EOR) methods assisted by gravity drainage mechanism and application of sophisticated horizontal wells bring new hope for heavy oil extraction. Variety of thermal and non-thermal EOR techniques inject an external source of energy and materials such as steam, solvent vapor, or gas through a horizontal well at the top of the reservoir to reduce in-situ heavy oil viscosity. So, the diluted oil becomes mobile and flows downwards by gravity drainage to a horizontal producer located at the bottom of the reservoir. In this paper, a sector model of an Iranian fractured carbonate heavy oil reservoir was provided to simulate and evaluate capability of some EOR techniques such as...

Improving Workflow in Microservice Architecture-Based Systems Using Process Mining with the Alloy Analyzer

, M.Sc. Thesis Sharif University of Technology Heidary, Behanm (Author) ; Mirian Hosseinabadi, Hassan (Supervisor)

Abstract

Microservices is a software architecture in which applications are divided into a collection of small, independent services. Each of these services is responsible for a specific part of the application's functionality and is developed, implemented, and run independently. Microservices emerged as a solution to the problems in traditional monolithic architectures. Today, microservice is known as the main candidate for building scalable cloud-based systems. In this architecture, a system is built using the integration of a number of microservices. This architecture is defined by two approaches in terms of the workflow model; In the first approach, the model of workflow and interaction between...

Advances in heuristic signal processing and applications

, Book ; Chatterjee, Amitava ; Nobahari, Hadi ; Siarry, Patrick

Springer 2013

Abstract

There have been significant developments in the design and application of algorithms for both one-dimensional signal processing and multidimensional signal processing, namely image and video processing, with the recent focus changing from a step-by-step procedure of designing the algorithm first and following up with in-depth analysis and performance improvement to instead applying heuristic-based methods to solve signal-processing problems. In this book the contributing authors demonstrate both general-purpose algorithms and those aimed at solving specialized application problems, with a special emphasis on heuristic iterative optimization methods employing modern evolutionary and swarm...

Optimal integration of small scale hybrid solar wind RO-MSF desalination system

, Article Renewable Energy Focus ; Volume 27 , 2018 , Pages 120-134 ; 17550084 (ISSN) Heidary, B ; Tavakoli Hashjin, T ; Ghobadian, B ; Roshandel, R ; Sharif University of Technology

2018

Abstract

Solar and wind are two main resources of renewable energies that can supply the energy requirement in the most of world's regions. Iran has desirable condition in terms of solar and wind energy and also is faced with shortage of fresh water resources. Hybrid solar wind RO-MSF desalination system that works with two clean and renewable energy resources of solar and wind, could be a sustainable energy resource for water desalination. Hence, in this paper for evaluating the performance of salty water desalination by hybrid RO-MSF desalination plants, a hybrid system is designed and optimized. Different models of solar wind RO-MSF was considered and analyzed technically and economically. Finally...

Comparison of microstructural changes in a SIMA processed A356 aluminum alloy after unidirectional compression and rolling: Effect of pressure depth

, Article Semi-Solid Processing of Alloys and Composites 10 - Selected, peer reviewed papers from the 10th International Conference on Semi-Solid Processing of Alloy and Composites, S2P 2008, Aachen, 16 September 2008 through 18 September 2008 ; Volume 141-143 , 2008 , Pages 391-396 ; 10120394 (ISSN); 9771012039401 (ISBN) Hajian Heidary, M ; Bigdeli, M ; Mahdavi, A ; Khomamizadeh, F ; Sharif University of Technology

Trans Tech Publications Ltd 2008

Abstract

In this study, in order to compare effect of unidirectional compression and rolling on final microstructure of strain induced melt activated (SIMA) A356 aluminum alloy, rectangular samples with dimensions of 3cm×5cm in area and 1cm in thickness and cylindrical specimens with 2.5cm in diameter and 1cm in length, have been prepared for rolling and compressing processes, respectively. Then, these samples were plastically deformed at a same strain in ambient temperature. Afterward, the strained samples were cut into equal quarters. In the next stage, to produce globular microstructure, these specimens were partially remelted in 580°C for different times. Results obtained from light microscopy...

Study of microstructural evolution and phase's morphology after partial remelting in A356 alloy

, Article Semi-Solid Processing of Alloys and Composites 10 - Selected, peer reviewed papers from the 10th International Conference on Semi-Solid Processing of Alloy and Composites, S2P 2008, Aachen, 16 September 2008 through 18 September 2008 ; Volume 141-143 , 2008 , Pages 367-372 ; 10120394 (ISSN); 9771012039401 (ISBN) Mahdavi, A ; Bigdeli, M ; Hajian Heidary, M ; Khomamizadeh, F ; Sharif University of Technology

Trans Tech Publications Ltd 2008

Abstract

In this work, effective parameters of SIMA process to obtain non dendritic microstructure in A356 alloy were investigated. In addition, the effect of SIMA process on the evolution of morphology of silicon and intermetallic phases in this alloy was studied. Microstructure images obtained from optical microscopy and SEM observation showed that increase in plastic work up to 40% and then holding of samples in the semi solid state at temperature of 580°C, causes that primary dendritic structure changes to non dendritic, fine and globular structure, but optimum reheating time completely depended on initial thickness of samples. If all parameters of SIMA process are the same, the grain boundaries...

Anomaly Based Intrusion Detection in Computer Networks Using Generative Adversarial Networks

, M.Sc. Thesis Sharif University of Technology Heidary, Milad (Author) ; Hemmatyar, Ali Mohammad Afshin (Supervisor)

Abstract

Due to the rapid development of computer networks, security is a major concern. Methods of intruding computer networks are also rapidly developing, and there is a new method every day. These facts corroborate the need for new and more intelligent mechanisms for detecting intrusion. To detect intrusion, one must analyze the network traffic. The most used traditional methods of traffic separation are port-based and payload based detection. The former is not so efficient, and the latter is not only inefficient but also violates the privacy of users. Unsatisfied by such methods, researchers adopted machine learning techniques and tried to develop new solutions for detecting intrusion. Methods...

Automatic Identification of Hazard Factors in Project Planning Phase Using Building Information Modeling (BIM)

, M.Sc. Thesis Sharif University of Technology Heidary, Mohammad Saeed (Author) ; Alvanchi, Amin (Supervisor) ; Karimi, Hossein (Supervisor)

Abstract

The construction is classified as a high-risk industry. The number of casualties and fatalities in this industry is disproportionately high. The ability to recognize hazards in the construction process and the design stage is still in its early stages of development. The most important way to control and eliminate hazards and accidents is to analyze these hazards before they occur and plan to deal with them before starting project activities. Identifying safety risks is the first step in evaluating and analyzing these risks. Building Information Modeling (BIM) technology, due to the consideration of the relationship between the elements in the model and because it contains an object-oriented...

Technical, Economic and Environmental Study and Evaluation of Urea and Ammonia Production Process

, M.Sc. Thesis Sharif University of Technology Heidary Doost, Mahdi (Author) ; Farhadi, Fatollah (Supervisor) ; Vafa, Ehsan (Supervisor)

Abstract

process design and decision-making about it are challenging activities that involve optimizing conflicting goals such as cost, technical feasibility, and environmental impacts. These conflicting goals can be analyzed by considering the complete life cycle of a process or product in the initial design and decision-making. Life cycle analysis follows the environmental effects throughout the life cycle of a product, including extraction, transportation, production, consumption, and disposal. Life cycle assessment includes four fundamental stages: goal and scope definition, inventory analysis, life cycle impact assessment, and interpretation of results. The aim of this project is to investigate...

Development of an Evolutionary Algorithm Based on Surrogate Models to be used in Multi-disciplinary Design Optimization of a Flying Vehicle

, M.Sc. Thesis Sharif University of Technology Ghoreishi, Mohaddeseh (Author) ; Nobahari, Hadi (Supervisor)

Abstract

In this research, multi-disciplinary design optimization (MDO) of a flying vehicle has been done based on the flight simulation. A meta-heuristic algorithm called Multi-objective Adaptive Real-coded Memetic Algorithm (MARCOMA) has been used for optimization. Since solving a MDO problem is a time consuming process, a RBF neural network has been used in the optimization algorithm as a surrogate model. The new algorithm, called MARCOMA+NN, has been tested with some standard benchmarks. MDO problem has six disciplines consists structure, aerodynamic, propulsion, guidance, control, and fire control. The MDO problem has 31 design variables and two objective functions. The objective functions are...

Optimal Design and Real-time Implementation of a Cooperative Guidance Algorithm against a Flying Vehicle

, M.Sc. Thesis Sharif University of Technology Motie, Mahyar (Author) ; Nobahari, Hadi (Supervisor)

Abstract

A cooperative aerial system to defense a Ground Station (GS), against an Incoming aerial Targets (IT) is presented. GS is surrounded by given terrains and a group of homogenous Unmanned Aerial Vehicles (UAVs) are employed using a novel online guidance algorithm in a decentralized manner. The proposed algorithm includes loiter, midcourse and terminal phases. During loiter; UAVs follow an optimal circular path. IT is supposed to approach GS along an optimal low altitude trajectory with respect to the terrains. UAVs are informed the initial position and velocity of IT and they are unaware of IT trajectory. Each UAV decides on whether to engage with IT or not, and shares its decision with other...

Synthesis and Characterization of PVDF Magnetic Nanocomposite

, M.Sc. Thesis Sharif University of Technology Hadi, Mina (Author) ; Forounchi, Massoud (Supervisor)

Abstract

PVDF (polyvinylidene fluoride) magnetic nanocomposite films were prepared by solution casting using two types of nanomagnetic particles: (i) magnetic nanoparticles synthesized by using an alkaline solution of mixed ferrous/ferric salts along with oleic acid as a coating agent at 70˚C; (ii) Fe3O4 nanoparticles prepared by hydrolysis of aqueous solution of ferrous/ferric salts with potassium hydroxide at room temprature. Scanning electron microscopy (SEM) showed that the PVDF magnetic nanocomposite had a porous structure with Fe3O4 nanoparticles dispersed inside the porous polymer matrix. The presence of crystalline magnetite within the polymer matrix was confirmed by X-Ray diffraction method...

Cooperative Search and Localization of Mobile RF Ground Targets, Using a Group of UAVs

, M.Sc. Thesis Sharif University of Technology Effati, Meysam (Author) ; Nobahari, Hadi (Supervisor)

Abstract

In this project, a method for cooperative search and localization of RF ground moving targets by a group of UAVs is developed. It should be noted that UAVs are just equipped with GPS and directional sensors. Since there is fuel constraint for UAVs, they take fuel from a tanker whenever they require. Moreover, searching method enables the UAVs to see different parts of the desired area with almost uniform distribution. In addition, the proposed approach enables the UAVs to perform a local search with the aim of finding the targets having lost their signal during localization mode. Finally, based upon a fueling decision function the UAVs take turn, approach to the fuel tanker, and start...

Attitude Control of a 3DOF Quadrotor Stand Using Intelligent Back-stepping Approach

, M.Sc. Thesis Sharif University of Technology Abeshtan, Peyman (Author) ; Nobahari, Hadi (Supervisor)

Abstract

In this research a novel intelligent back-stepping control method is developed. This method is robust to sensor noise and external disturbances. In addition, the controller is robust under model uncertainty. This controller does not need precise knowledge of system parameters. This method is based on three methods of: back-stepping control, least squares estimation and a fuzzy compensator. This controller is used to control quadrotor stand witch is like an inverse pendulum. In quadrotor stand modeling, the inverse pendulum effect is considered too, witch is one of the innovations of the research. By doing various simulations, the validity of controller is tested. Also the performance of the...

Cooperative Search and Localization of Aerial Targets, Using a Group of Fixed Wing UAVs

, M.Sc. Thesis Sharif University of Technology pourhaji, Amir (Author) ; Nobahari, Hadi (Supervisor)

Abstract

Topic that is investigated in this article include identify and localization a number of aerial target penetrating into a protected by area by a swarm of UAVs is fixed wing. UAVs do not have any prior notice of positioning targets. In addition, it is assumed that lacks any radiation exploitable targets and thus use UAVs for Targets Detection from an active radar system. Obviously this article focus on developing a guidance algorithm UAVs to this particular issue and also as the targets participatory is localization algorithm. In addition, extraction type and performance characteristics radar system required and also performance characteristics of the class of UAVs, which is suitable to...

A New Method for Integrated Controller and Observer Design of a Nonlinear System Using Genetic Programming

, M.Sc. Thesis Sharif University of Technology Khosroabadi, Saleh (Author) ; Nobahari, Hadi (Supervisor)

Abstract

The purpose of this paper is to design an integrated controller and observer (ICO) for a nonlinear system using genetic programming. ICO is a function that constructs control command directly from the measured state variables of the system. It means that, this function should imitate the behavior of the observer and controller and control the system with acceptable performance in different initial conditions, at the presence of disturbances and system uncertainties. The complexity of this design method, is not related to the complexity of the plant, in fact, the complexity in plant just effects at run time, but the design procedure does not change. So, if exact model of plant exist, using...