Adaptive control strategy for treatment of hepatitis C infection

, Article Industrial and Engineering Chemistry Research ; Volume 58, Issue 33 , 2019 , Pages 15262-15270 ; 08885885 (ISSN) Zeinali, S ; Shahrokhi, M ; Sharif University of Technology

American Chemical Society 2019

Abstract

In this work, an efficient treatment strategy for hepatitis C disease using interferon (IFN) has been proposed on the basis of the back-stepping control technique. The basic model of the hepatitis C virus (HCV) has been considered for controller design. To tackle the problem of model parameter variations, the adaptive version of the back-stepping method has been utilized. For applying the proposed treatment, all states should be available while only the viral load is measured. To solve this problem, a nonlinear Luenberger-like observer has been designed to estimate the unmeasured states. In the proposed treatment, limitation of the drug efficacy has been taken into account. Asymptotical...

Observer-based singularity free nonlinear controller for uncertain systems subject to input saturation

, Article European Journal of Control ; Volume 52 , 2020 , Pages 49-58 Zeinali, S ; Shahrokhi, M ; Sharif University of Technology

Elsevier Ltd 2020

Abstract

In this work, design of an observer-based nonlinear controller for a class of single input-single output (SISO) systems in the general strict feedback form subject to input saturation based on the back-stepping technique has been addressed. A full order adaptive observer is constructed to estimate the unknown states and system parameters simultaneously. The proposed control scheme is singularity free and can handle the input nonlinearity. Asymptotical stability of the closed-loop system in the presence of observer dynamics and input saturation has been established by the Lyapunov stability theorem. The effectiveness of the proposed controller is illustrated by applying the proposed scheme to...

Text-Independent Speaker Identification in Large Population Applications

, M.Sc. Thesis Sharif University of Technology Zeinali, Hossein (Author) ; Sameti, Hossein (Supervisor)

Abstract

The human speech conveys much information such as semantic contents, emotion and even speaker identity. Our goal in this thesis is the task of text-independent speaker identification (SI) in large population applications. Identification (test) time has become one of the most important issues in recent real time systems. Identification time depends on the cost of likelihood computation between test features and registered speaker models. For real time application of SI, system must identify an unknown speaker quickly. Hence the conventional SI methods cannot be used. The main goal in this thesis is to propose several methods that reduced identification time without any loss of identification...

Controller Design for A Nonlinear System in the Absence of Full State Measurements

, M.Sc. Thesis Sharif University of Technology Zeinali, Sahar (Author) ; Shahrokhi, Mohammad (Supervisor)

Abstract

In this study design of controller for a nonlinear system in the presence of state observer was investigated. First, nonlinear observers including non-adaptive and adaptive versions and their design procedures were studied. Then nonlinear adaptive controllers, based on sliding mode, feedback linearization and back-stepping techniques were implemented in the presence of observer dynamics. Two versions of adaptive law were proposed for unknown parameters identification in feedback linearization and sliding mode techniques. A new adaptive law was proposed to relax the restrictive condition that is used in adaptive observer design. The closed loop stability of back stepping technique was studied...

A Superhydrophobic Melamine Formaldehyde Sorbent for Micro Extraction of Pollutants from Aquatic Media

, M.Sc. Thesis Sharif University of Technology Zeinali, Shakiba (Author) ; Bagheri, Habib (Supervisor)

Abstract

In this project, melamine formaldehyde was chosen as initial substrate for its high porosity. Then for having superhydrophobic surface, surface functional groups were silanized and deactivated as a result. It was assumed that high porosity of prepared sorbent and its nonpolar nature, can increase extraction efficiency. To study extraction efficiency of the prepared sorbent, it was filled inside a needle and used for needle-trap head-space extraction of BTEX (abbreviation for Benzene, Toluene, Ethylbenzene and Xylenes). Needle packed with sorbent was held on headspace of sample containing BTEX and head- space was pumped with a peristaltic pump. Pumping introduces fresh sample to sorbent...

Hodge Structure on Fundamental Groups

, M.Sc. Thesis Sharif University of Technology Zeinali, Nima (Author) ; Jafari, Amir (Supervisor)

Abstract

Deligne Proved that cohomology groups of algebraic varieties over C have mixed Hodge structures.It is also proved that homotopy groups of these varieties have mixed Hodge structures in a proper sense.In this thesis using iterated integrals that introduced by Chen,we explain Hain’s approach for defining Hodge structures on truncated first homotopy groups(fundamental groups). Note that there is another approach for defining Hodge structures on homotopy groups by Morgan,that uses minimal models of Sullivan.For explaining Hain’s approach,some basic results on Hodge structures are also explained

Investigation of the Effect of Particulate Emissions From Steel Complex on Adjacent Urban Areas Using Source and Receptor Modeling Approaches

, M.Sc. Thesis Sharif University of Technology Zeinali, Shervin (Author) ; Torkian, Ayoob (Supervisor)

Abstract

Expansion of city boundaries as a result of increased population has reduced the distance from industrial complexes and health effects of industrial air pollution have been intensified. As such, studies are needed to determine appropriate methodologies for quantifying the effect of these industries on the concentration of air pollutants in urban areas. In this study, particulate emissions from a steel mill complex was modeled using ADMS4 and the predicted results were compared with actual measurements made in the adjacent urban area. A receptor model (CMB8.2) was also used to quantify the share of the steel mill on the heavy metals' concentrations in the city by considering other sources...

Risk Assessment of Probable Domino Scenarios Between Two Petrochemical Units

, M.Sc. Thesis Sharif University of Technology Zeinali, Nassim (Author) ; Rashtchian, Davood (Supervisor)

Abstract

Hazard analysis and risk assessment are the two significant methods of controlling and reducing risk caused by industrial units. To achieve the required safety needed in either new or operating plants, risk assessments are being used for some specific hazards such as fire, explosion and toxic release. Increasing industrial developments and occurrence of several catastrophic accidents in chemical processing plants have contributed to striking disasters and have obliged experts to use analytical solutions to evaluate frequencies and consequences of such events. Congested plants in industrial areas like Mahshahr and Asalouyeh in Iran and other places in the world are the reason why it has...

Proposing a Stable Treatment Strategy for Hepatitis C

, Ph.D. Dissertation Sharif University of Technology Zeinali, Sahar (Author) ; Shahrokhi, Mohammad (Supervisor)

Abstract

The purpose of this study is to propose a stable treatment strategy for hepatitis C infection by considering several practical limitations of the treatment and using control theories. First, hepatitis C disease and its transmission, diagnosis, and treatment methods have been introduced. Then, the mathematical models of hepatitis C dynamics in the body have been presented, and their ability in predicting the observed clinical behaviors of the patients has been studied. Thereafter, the extended versions of these models by considering pharmacokinetics/dynamics equations of the drugs have been proposed to have a more realistic mathematical model. After that, the practical features of the disease...

Improving Robustness of Speaker Verification Systems Against Non-Identity Information

, Ph.D. Dissertation Sharif University of Technology Zeinali, Hossein (Author) ; Sameti, Hossein (Supervisor)

Abstract

Speaker verification as a kind of biometric methods aims to verify the identity of a person from characteristics of their voice. This method faces many challenges such as voice imitation (spoofing), use of recorded voice, high sensitivity to convolutive distortions resulted by channel, and a large performance degradation for short-duration utterances. The aim of this thesis is to propose different methods for reducing the effects of non-identity information,especially the channel, and also solving the problem of new methods for text-dependent speaker verification with very short utterances. i-vector has been the best speaker modeling method in recent years but it doesn’t result in good...

Modified Polystyrene Based Sorbents for Extraction of Trace Organic Pollutants with a Wide Range of Polarity

, Ph.D. Dissertation Sharif University of Technology Zeinali, Shakiba (Author) ; Bagheri, Habib (Supervisor)

Abstract

The main focus of this thesis is based on surface modification of polystyrene in order to prepare extractive phases appropriate for extraction of analytes with a wide polarity range. This goal was achieved by increasing surface polarity. In fact, improved wettability and the possibility of interaction with polar analytes after addition of functional groups on polystyrene surface were the main reason for increased extraction capacity. In the first research, different functional groups including amine, nitro, carboxyl and acetyl were added on polystyrene particles by chemical bonding and to investigate their influence on extraction process, 22 analytes with a wide polarity range (LogP=-2 to...

Optimal Control of Spacecraft on the Earth-Moon Lagrange Point Orbits considering Sun and other Planets and Elliptic Orbit Perturbations

, M.Sc. Thesis Sharif University of Technology Ghorbani, Mehrdad (Author) ; Assadian, Nima (Supervisor)

Abstract

In this thesis, optimal station keeping of spacecraft on the closed-orbits near the Earth-Moon Lagrange points has been investigated. Lagrange points L1 and L2 are unstable equilibrium points of the circular restricted three-body problem (CRTBP), and periodic orbits near them are the destination of modern missions. However, perturbations resulting from the gravitational forces of the Sun and the planets and the eccentricity of the orbit of the Moon around the Earth make the Lagrange point unstable, even L4 and L5, which are stable in CRTBP. The most suitable choice for spacecraft mission near the collinear Lagrange points is the Halo and other closed-orbits around them, which need...

Orbit Design and Optimization of Satellite Constellation for Regional Coverage

, M.Sc. Thesis Sharif University of Technology Borhani, Amir (Author) ; Assadian, Nima (Supervisor)

Abstract

In this thesis, the satellite constellation orbit design for regional coverage is investigated. The orbits of satellites in a constellation for Earth observation missions play a crucial role in performance and characteristics of the mission; for example the image resolution, the area of coverage, and the coverage interval. In this thesis the problem is to find the optimal initial orbital elements for meeting the earth observation mission objectives for one or several sites. The cost functions are the total coverage time, the maximum gap time, time average gap, altitude, and number of satellites. The problem is solved in a multi-objective manner for different combination of two of the above...

Autonomous Orbit Estimation for Regional Navigation Satellites

, M.Sc. Thesis Sharif University of Technology Memaran, Mohsen (Author) ; Asadian, Nima (Supervisor)

Abstract

In this thesis, autonomous orbit estimation of regional navigation satellites has been investigated. Estimation of satellite orbit is an integral part of satellite navigation, which may be executed via assistance of ground station. As the satellite is exposed to the ground station view, range, direction and rate of range is measured by mean of ranging instrumentation relative to ground reference, hence the precise position is calculated. In this thesis a set of satellites are investigated in a unique structure called constellation with the purpose of navigation. The occurrence which is likely to happen in this condition, is the failure of ground station under certain circumstances or losing...

Fabrication and Characterization of a UF Ceramic Membrane based on TiO_2 Nanoparticles

, M.Sc. Thesis Sharif University of Technology Mirkazemi, Amin (Author) ; Taghavinia, Nima (Supervisor)

Abstract

UF membranes are widely used in various industries now, a major type of these membranes are ceramic membranes which are resistant to high temperatures and corrosive fluids. In this thesis we developed an anisotropic UF ceramic membrane based on 20nm TiO2 nanoparticles on a prous sustrate. We had two major challenges, the first one was to find a suitable prous substrate and the second one was to find an appropriate coating method. Our main task was to optimise the process conditions to achive a crackless and uniform membrane layer with minimal ups and downs. Lots of coating methods and TiO2 inks have been tried, finally we used a coating method which we called it “Soft Blade Coating”, with...

Continuous-thrust Trajectory Optimization in the Binary Asteroids System

, M.Sc. Thesis Sharif University of Technology Ashrafi, Mehnraz (Author) ; Asadian, Nima (Supervisor)

Abstract

In this thesis, the optimal trajectories of a spacecraft in the binary asteroids system is studied. The objective functions of optimal trajectories in these system are the maximum coverage of the asteroids surface and minimum time and fuel consumption. For this purpose, the dynamic of binary system is modeled. The binary system of 1999 KW4 is selected as a case study. The ellipsoid-sphere model is a good approximation for the case of this study. In this model, the asteroids orbit in a circular orbit around each other in a spin-spin-orbit resonance configuration, in which the asteroids’ rotational velocity is equal to orbital mean motion. Then, the equations of motion of the spacecraft as the...

Fault-tolerant Attitude Control of Sattelite Using Neural Networks

, M.Sc. Thesis Sharif University of Technology Sepehr, Firoozeh (Author) ; Asadian, Nima (Supervisor)

Abstract

This research aims to introduce a new integrated fault tolerant attitude control system of satellites based on the neural networks. First, a linear controller and an optimal controller are designed assuming that no fault occurs in the reaction wheels of the satellite. It is obvious that these controllers are not able to respond properly when a fault occurs. Therefore, artificial neural networks are employed in the fault tolerant controller design. Neural networks are well-known for their adaptiveness and the ability to learn the dynamics of a system. Therefore, they can be used to predict the faulty conditions. In this research two approaches are examined to deal with the faulty conditions....

Fabrication and Characterization of Inverted Perovskite Solar Cells Using Nickel Oxide as Hole Transporting Layer

, Ph.D. Dissertation Sharif University of Technology Saki, Zahra (Author) ; Taghavinia, Nima (Supervisor)

Abstract

In this research, we study and optimize the inverted perovskite solar cells (PSCs) using nano layers of NiOx and Li:NiOx as hole transporting layers (HTLs) and nano layers of PC70BM and C60 as electron transporting layers (ETLs). We fabricated inverted PSCs with three different HTLs, namely MoOx, PEDOT:PSS and NiOx, using vapor assisted solution processed (VASP) method for making MAPbI3 perovskite which yielded a power conversion efficiency (PCE) of 1%, 1.93% and 3.65%, respectively. Solution-processed deposition method, high transparency (˃90%) and high band gap (3.9 eV) are the most advantages to use NiOx as HTL in current research. Using lithium as dopant to the NiOx increases the...

Dynamics of Tethered Satellite Formation Around Binary Asteroids

, M.Sc. Thesis Sharif University of Technology Bakhshipour, Mehran (Author) ; Assadian, Nima (Supervisor)

Abstract

Studying of binary asteroids because of achieving data of existence sources in the world persuades to investigate about tethered satellite formation around binary asteroids in future missions. About 20 percent of asteroids around the sun are binary asteroids. It is going to analyse dynamics of tethered satellite around Didymos binary asteroid. Light mass of the asteroid is good reason to consider gravitational harmonic perturbation, and leads to attention about solar radiation pressure depends on distance in modelling of the dynamical system. It will be zonal harmonics up to second order and sectoral. Satellites are such a particle as an assumption; that is why attitude motion of satellites...

Fractional Order Modeling and Control of Flexible Satellite

, M.Sc. Thesis Sharif University of Technology Hosseini, Masoud (Author) ; Assadian, Nima (Supervisor)

Abstract

In recent decades the structure of space systems has gained more complexity due to the development of space technology. Usage of larger structure in spacecraft could cause undesirable structural vibration. mNeglecting this phenomena would affect the performance of satellite subsystems specially the accuracy of satellite control subsystem. By implementing fractional order calculus in modeling of flexible satellite, the damping effect could be modeled better than classical damping model. Also using fractional order integrator and differentiator operator will increase the performance of control subsystem. In this research, the fractional order calculus has been used in modeling and control of...