Control of a Sprayer Hexacopter with Continuous Varying Mass in the Presence of Fluid Sloshing Disturbance

, M.Sc. Thesis Sharif University of Technology Borhani, Mohammad (Author) ; Alasty, Aria (Supervisor) ; Vosughi, Gholamreza (Supervisor)

Abstract

Unmanned aerial vehicles (UAVs), particularly hexacopters, are increasingly used in agricultural spraying due to their high payload capacity and stable flight performance. However, changes in liquid mass during spraying alter flight dynamics, and fluid sloshing within the tank introduces internal disturbances that may affect stability. This study presents an Active Disturbance Rejection Control (ADRC) for velocity control of spraying hexacopters to maintain performance under varying mass and internal/external disturbances. A real tank was used to analyze variations in the fluid’s center of mass under different conditions, revealing a nearly spherical distribution. Based on this, a...

Experimental Study and Prediction of Vancomycin Partitioningin Surfactant-Salt Aqueous Two-Phase Systems

, M.Sc. Thesis Sharif University of Technology Shirvani, Sara (Author) ; Vosughi, Manouchehr (Supervisor) ; Rashtchian, Davood (Supervisor) ; Pazuki, Gholamreza (Supervisor)

Abstract

In the past years, upstream processes have been receiving a considerable R&D investment and commercial attention. The downstream processes have, however, been overlooked causing a production bottleneck that is shifting the costs of production from up to downstream. The need to develop more efficient and cost-effective separation and purification processes is, thus, crucial in order to improve process efficiency and economics keeping the required high standards of quality for market approval. In this research, promising aqueous two-phase systems (ATPS) containing Tween 20 as a quite biocompatible non-ionic surfactant and different salts (K3Citrate and NaH2PO4) were prepared and their...

Speed Optimization In Hardware Implementation Of JPEG2000

, M.Sc. Thesis Sharif University of Technology Bayat, Mina (Author) ; Vosughi Vahdat, Bijan (Supervisor)

Abstract

According to needs for high quality pictures with high compression, in variety of applications such as Satellite communications, in this thesis some parts of JPEG2000 standard with computation and time complexity, have been implemented on FPGA. This parts are:
1- Two dimensional Discrete wavelet transform (2D-DWT)
2- Bit Plan Coding
3- Context-based Adaptive Binary Arithmetic Coding (MQ-Coder)
Each of these parts is implemented on basis of the best architectures in papers with some improvement on its hardware; and the results are compared with other similar works. Other parts, such as “Packet Creation” that are intrinsically software-based, are not implemented and it is...

Modeling of Human Decision Making in Problem Solving Based on Physiological Models of Neuron

, M.Sc. Thesis Sharif University of Technology Shirzadeh, Hossein (Author) ; Vosughi Vahdat, Bijan (Supervisor)

Abstract

How the human nervous system works is one of the most important topics in science and in this topic providing a model of it is scientists' main concern. The human brain that has been formed from a large number of nerve cells lets it do complex computations. The structure of cognition, memorizing and processing which are some of human features are being studied in many fields of science named "brain and cognitive science".
In this study, we will point to modeling of one of the human cognitive phenomena (decision making in problem solving). In this modeling, we aim to connect the microscopic and macroscopic levels of the nervous system to each other.
First, we will give an introduction...

A Learning Method Inspired by the Human Motor Learning

, M.Sc. Thesis Sharif University of Technology Davoudi, Heydar (Author) ; Vosughi Vahdat, Bijan (Supervisor)

Abstract

Recently, the computational algorithms underlying in the nervous system of vertebrates have been attracting scientists and engineers. Therefore, a number of artificial learning methods are proposed for mathematical interpretation of these algorithms. In this thesis, by investigating the latest findings about the nervous system, and the motor system in particular, a novel machine learning scheme inspired by human motor learning is proposed. Basic theoretical aspects of this method in conjunction with some of state-of-theart artificial learning methods are discussed. Finally, this method is evaluated in a variety of engineering problems ranging from curve fitting and function approximation to...

Epileptic seizure detection using AR model on EEG signals

, Article 2008 Cairo International Biomedical Engineering Conference, CIBEC 2008, Cairo, 18 December 2008 through 20 December 2008 ; February , 2008 ; 9781424426959 (ISBN) Mousavi, R ; Niknazar, M ; Vosughi Vahdat, B ; Sharif University of Technology

2008

Abstract

This study presents a new method for epilepsy detection based on autoregressive (AR) estimation of EEG signals. In this method, optimum order for AR model is determined by Bayesian Information Criterion (BIC) and then AR parameters of EEG signals (from EEG data set of epilepsy center of the University of Bonn, Germany) and their sub-bands (created with the help of wavelet decomposition) are extracted based on it. These parameters are used as a feature to classify the EEG signals into Healthy, Interictal (seizure free) and Ictal (during a seizure) groups using multilayer perceptron (MLP) classifier. Correct classification scores at the range of 91% to 96% reveals the potential of our approach...

Improving the Method of Face Recognition

, M.Sc. Thesis Sharif University of Technology Rabiepour, Siavash (Author) ; Vosughi Vahdat, Bijan (Supervisor)

Abstract

Face recognition is one of the best biometrics in computer vision. Although researchers introduced this method many years ago, the most important improvement has occurred in the biometrics last decade. Face recognition was employed in areas such as passport checking, security issues and identification. It facilitates our daily life as we use it in our mobile phones and computers for unlocking our devices. Many approaches were employed in the face recognition applications. Some of them were single-modal like PCA, ICA and LDA and some others were multimodal like Visual + 3D or 3D + IR. Still, most of Face recognition methods suffer from environment changes like variations in illumination and...

Stimulus Signal Improvement in Order to Alleviate the Symptoms of Parkinson's Disease in Rat

, M.Sc. Thesis Sharif University of Technology Gholipour, Saman (Author) ; Vosughi Vahdat, Bijan (Supervisor)

Abstract

Parkinson's disease is a degenerative disorder of the central nervous system. The motor symptoms of Parkinson's disease result from the death of dopamine-generating cells in the substantia nigra. The cause of this cell death is unknown. Early in the course of the disease, the most obvious symptoms are movement-related. Some of the symptoms are: shaking, rigidity, slowness of movement and difficulty with walking and gait. Modern treatments are effective at managing the early motor symptoms of the disease, mainly through the use of levodopa and dopamine agonists. As the disease progresses these drugs eventually become ineffective and produce a complication called dyskinesia, marked by...

Investigation of Multidimensional Recording Brain Signal (ECoG) For Estimation of 3D Arm Trajectory

, M.Sc. Thesis Sharif University of Technology Babolhavaeji, Ali (Author) ; Vosughi Vahdat, Bijan (Supervisor)

Abstract

The main idea in this project is investigation of multidimensional recording brain signal (ECoG) for estimation of 3D arm trajectory. First we introduce a general structure with variable blocks, in this structure we have many ways to estimate hand trajectory and obtain different result. By statistical test we find the best state of this structure and apply it on other dtae set trials. Electrocorticography (ECoG) has seen recent use in this regard because it offers a higher spatiotemporal resolution than non-invasive EEG and is less invasive than intracortical microelectrodes and have been shown to contain reliable information about the direction of arm Trajectory and movements. We using...

Designing a 32-Bit Fault-Tolerant ALU Using EDAC

, M.Sc. Thesis Sharif University of Technology (Author) ; Vosughi Vahdat, Bijan (Supervisor) ; Mortazavi, Mohammad (Supervisor)

Abstract

Reliable communication has become very crucial in the transmission applications. Hence, to design hardware to handle reliability is the most important part of communication. In this work, we propose a new secured ALU (Arithmetic and Logic Unit) against fault attacks that is used in ARM processor which can correct any 5-bit error in any position of 32-bit input registers of ALU. We also designed a BCH (Bose, Chaudhuri, and Hocquenghem) codec (encoder, decoder) using the prototyping FPGA. Further, in this thesis we designed (63, 36) the BCH encoding and decoding system to tolerate the 5-bit faults. The codec system and ALU system are based on using Verilog description language. Since...

Developing a Correspondent Information Security Management System for Electronic Banking in Iran

, M.Sc. Thesis Sharif University of Technology Iravani, Yousef Esmaeil (Author) ; Vosughi Vahdat, Bijan (Supervisor)

Abstract

Growing need for the use of modern technologies in the field of information and communication reveals the necessity to establish an information security management system more than before. It is totally proven that information is an asset which, like other important assets of the organization is so momentous that should be crucially protected. Nowadays, with the proliferation of security threats, which can lead to undesirable events with possible damage to systems or organizations intentionally or inadvertently, by human factors or inhuman cause, existence of a safe structure has become more necessary for all organizations and agencies. One of the most critical areas of information security...

Modeling of Ethanol Production Technologies From Solid Waste and Evaluation of Ethanol Based Biofules in Energy System

, M.Sc. Thesis Sharif University of Technology Hashemi, Nasim (Author) ; Vosughi, Manoochehr (Supervisor) ; Saboohi, Yadollah (Supervisor)

Abstract

Considering finish ability of fossil fuels and their polluting effects accordingly a need of renewable energies is felt. Among these clean energies biomass considering economical and environmental advantages is one of bests. Therefore a sufficient energy¬-¬efficient process with a good efficiency is needed. In this study an analysis of different mechanism to produce bioethanol from biomass has been done. According to the results from simulation the recovery step of bioethanol from the existing dilute solution from fermentation consumes the most energy in the process. Therefore substituting saline extractive column can result in saving energy. Finally in order to get more accurate result the...

Design and Implementation of Multi-Lead ECG Holter Monitoring and Cardiac Arrhythmia Classification

, M.Sc. Thesis Sharif University of Technology Mousavi Bandarabadi, Hassan (Author) ; Vosughi Vahdat, Bijan (Supervisor)

Abstract

Cardiovascular diseases are currently the most common disease and the first cause of death in Iran and the world. It will increase in the future due to improper diet and lifestyle. Therefore, the prevention and treatment of these diseases is very important for the health of the country. One of the effective ways to diagnose heart diseases is to analyze the electrical signals of the heart and detect heart rhythm irregularities from it. The electrical signal of the heart called ECG is created by the electro-mechanical activity of the atria, ventricles and the valves between them. Therefore, this signal is useful for detecting the correct functioning of different parts of the heart and...

Treatment of Methamphetamine Addiction Using Transcranial Magnetic Stimulation

, M.Sc. Thesis Sharif University of Technology Rahimi Kandehlani, Zeinab (Author) ; Vosughi Vahdat, Bijan (Supervisor)

Abstract

Substance use disorder has always been one of the biggest challenges in the field of drug addiction. However, many substance use disorders have no drug treatment approved by the US Food and Drug Administration. Transcranial magnetic stimulation is a non-invasive brain stimulation method. Transcranial magnetic stimulation is expected to reduce cravings and risk of relapse by regulating brain function. The purpose of this study is to investigate the effect of transcranial magnetic stimulation on the treatment of methamphetamine addiction. In this research, the effect of transcranial magnetic stimulation twice a day on the left dorsolateral prefrontal cortex area of the brain during the time...

Design of a Fault Tolerant ARM-Based Processor on FPGA

, M.Sc. Thesis Sharif University of Technology Esmaeeli, Siamak (Author) ; Rashidian, Bijan (Supervisor) ; Vosughi Vahdat, Bijan (Supervisor)

Abstract

The charged particles in space strike the silicon surface of an embedded system in a satellite and cause fault occurrence in its operation. So some methods should be employed to reduce the effects of the faults. The methods that are implemented in system level are widely used because of their low cost and high reliability. The processors are responsible for performing main processes in embedded systems. On the other hand, the ARM processors are good choices for utilizing in satellites because of their low size, low power consumption and high performance. Also, FPGAs have made a major improvement in embedded system design. So with implementing ...

Pensim for Intel Architecture

, M.Sc. Thesis Sharif University of Technology Nasrollahi, Mahdi (Author) ; Vosughi Vahdat, Bijan (Supervisor) ; Mortazavi, Mohammad (Supervisor)

Abstract

To capture what is really done on the computer, we have decided to simulate the behavior of an Intel processor based computer. The main part of a computer is its CPU, so we are have simulated the Intel processors from 8086 to Pentium with MMX, SSEX and 3DNow. To work with hardware and software and going back to these steps for several times, is a time consuming procedure. To avoid falling in such loops, one way is to simulate the hardware and develop the software according to this simulation. This remedy solves time consuming procedure since changing hardware in simulation is quite easy. To simulate the digital systems, we need to have the software codes of the processors. Since the Intel...

Capacitive Copling for Energy Transmission to Implant

, M.Sc. Thesis Sharif University of Technology Ashiri, Mehrangiz (Author) ; Zahedi, Edmond (Supervisor) ; Vosughi Vahdat, Bijan (Supervisor)

Abstract

Neural prostheses (NPs) based on capacitive coupling method including sur-face NPs, implanted or subcutaneous NPs and Stimulus Route System (SRS) are the common NPs used for rehabilitation applications. SRS is a kind of capacitive coupling and the latest version of the mentioned neural prosthesis used for restoring sensory and motor functions caused by spinal cord and brain disorders. In addition to some superiorities of capacitive coupling compared to other methods (inductive coupling, batteries, energy harvesters and so on) such as at plates structure and consequently ease of manufacturing, ability to transfer data and power with different operating frequency and hence remov-ing...

Functional Mapping of Regions Involved In Addiction Using Magnetic Resonance Imaging and Proposing a New Measure for Multivariate Methods

, M.Sc. Thesis Sharif University of Technology Faghiri, Ashkan (Author) ; Vosughi Vahdat, Bijan (Supervisor) ; Ekhtiari, Hamed (Co-Advisor)

Abstract

Methamphetamine (meth) abuse and addiction (MA), with its serious medical, psychiatric and social complications, is a growing national disaster in Iran. Response control deficit during exposure to drug related cues is one of the main neurocognitive cores in MA and results in continued drug use and treatment failure. There have been many studies focused on cue exposure, but most of their paradigms required subjects to passively view the cues; this aspect of these paradigms cause a wide gap between reality and experimental studies. Developing a functional and structural neuroimaging protocol to map realistic brain circuits that are involved in craving among meth users is of importance....

Utilization of Different Optical Wavelengths in Diffractive Deep Neural Networks for Object Classification in Multi-Channel Images

, M.Sc. Thesis Sharif University of Technology Ebrahimi, Sevda (Author) ; Vosughi Vahdat, Bijan (Supervisor) ; Kavehvash, Zahra (Supervisor)

Abstract

Diffractive deep neural network is an optical machine-learning framework that uses diffractive surfaces, optical devices, electro-optic devices and engineered matterials to optically perform computational tasks. These diffractive networks, after their desing and train phase by computers and machine learning algorithms, are physically fabricated using 3D printing or lithography, to actualize the model of trained network. Machine learning processes and alghorithms are performed through light-matter interaction and diffraction of light. This procedure is done at the speed of light and without the need of any power, except for the light illumination for the input object. In comparison with...

Impedance Control of Flexible Base Moving Manipulators

, Ph.D. Dissertation Sharif University of Technology Salehi, Mahdi (Author) ; Vossoughi, Gholamreza (Supervisor)

Abstract

In this paper, the general research of impedance control is addressed for a robotic manipulator with a moving flexible base. Impedance control imposes a relation between force and displacement at the contact point with the environment. The concept of impedance control of flexible base moving manipulators (FBMM) is rather new and is being considered. The dynamic of manipulator is decomposed into slow and fast dynamics using singular perturbation method. New sliding mode impedance control method (SMIC), using an element on the end effector is proposed for high precision impedance control of FBMM. The sliding mode impedance control method as a robust impedance control law is derived for the...