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    Fault-Tolerant control of uncertain linear systems in the presence of L∞ disturbances and actuator saturation

    , Article 4th International Conference on Control, Instrumentation, and Automation, 27 January 2016 through 28 January 2016 ; 2016 , Pages 307-312 ; 9781467387040 (ISBN) Khatibi, M ; Haeri, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2016
    Abstract
    In this paper the fault-Tolerant control problem for uncertain linear systems in the presence of L, disturbances and actuator saturation is studied. The conflict between enlarging the domain of attraction and attenuating the effect of L, disturbances is tackled by proposing a non-constant state feedback controller. The feedback gains are calculated off-line by using linear matrix inequalities. In addition, the proposed method is capable of tolerating time-varying faults. The suggested approach is implemented on a sample model and the result is compared with other works  

    Fault-tolerant control considering time-varying bounds on faults

    , Article Transactions of the Institute of Measurement and Control ; Volume 40, Issue 10 , 2018 , Pages 2982-2990 ; 01423312 (ISSN) Khatibi, M ; Haeri, M ; Sharif University of Technology
    SAGE Publications Ltd  2018
    Abstract
    This paper presents a novel fault-tolerant control strategy to compensate the time-varying loss of actuators’ effectiveness. It considers intermediate situations where the fault is not determined precisely (unlike active approaches) but overall estimations about its rate and final value are available through the previous experiences and/or experiments. Based on the estimations, two upper and lower time-varying bounds on the actuators’ effectiveness are established to be exploited in the procedure of controller design. In a special case, where these bounds are constant, the method will be reduced to the conventional passive approach. Also, actuator saturation and the effects of (Formula... 

    A unified framework for passive–active fault-tolerant control systems considering actuator saturation and L ∞ disturbances

    , Article International Journal of Control ; Volume 92, Issue 3 , 2019 , Pages 653-663 ; 00207179 (ISSN) Khatibi, M ; Haeri, M ; Sharif University of Technology
    Taylor and Francis Ltd  2019
    Abstract
    This paper presents a unified passive–active fault-tolerant control strategy to compensate the loss of actuators’ effectiveness. The proposed approach is capable of handling the system in pre- and post-fault diagnosis intervals by passive and active approaches, respectively. The stability of the designed system is independent of the accuracy of information provided by the fault detection and diagnosis unit, however, a precise estimation could improve the conservation. Actuator saturation and L ∞ disturbances effects are considered in the design stage. The trade-off between maximising the domain of attraction and minimising the effects of L ∞ disturbances is tackled by developing a... 

    A unified framework for passive–active fault-tolerant control systems considering actuator saturation and L∞ disturbances

    , Article International Journal of Control ; 2017 , Pages 1-11 ; 00207179 (ISSN) Khatibi, M ; Haeri, M ; Sharif University of Technology
    2017
    Abstract
    This paper presents a unified passive–active fault-tolerant control strategy to compensate the loss of actuators’ effectiveness. The proposed approach is capable of handling the system in pre- and post-fault diagnosis intervals by passive and active approaches, respectively. The stability of the designed system is independent of the accuracy of information provided by the fault detection and diagnosis unit, however, a precise estimation could improve the conservation. Actuator saturation and L∞ disturbances effects are considered in the design stage. The trade-off between maximising the domain of attraction and minimising the effects of L∞ disturbances is tackled by developing a non-constant... 

    Fault Tolerant Control Considering Actuator Saturation and External Disturbances

    , Ph.D. Dissertation Sharif University of Technology Khatibi, Mahmood (Author) ; Haeri, Mohammad (Supervisor)
    Abstract
    A control system capable of tolerating system malfunctions while maintaining an acceptable level of performance is referred as fault tolerant control system. The constraints on the amplitude of input control signals limit the domain of attraction even for linear models. Ignoring this fact may lead to an unsatisfactory performance and even closed loop instability. Designing the controller such that the domain of attraction is maximized has been an attractive topic for researchers. On the other hand, persistent disturbances always play an essential role in the real word systems. Designing the controller in a way such that the effect of such disturbances is attenuated is another challenging... 

    Development of Regional Rainfall-Runoff Models

    , M.Sc. Thesis Sharif University of Technology Khatibi, Sahar (Author) ; Abrishamchi, Ahmad (Supervisor)
    Abstract
    Hydrological models are suitable tools for reduction of hydrological uncertainty in stream flow estimation. There are different historical approaches for the development of rainfall-runoff models, with regard to the choice of model structure and the calibration of the parameters, but the most attention has been focused on gauged catchments where sufficient data, in particular stream flow data, are available. So new modeling strategies for ungauged or pseudo ungauged catchments have been developed. This work was aimed to develop a methodology for the regionalization of some parameters of a conceptual rainfall-runoff model based on measurable physiographic, meteorological and even land... 

    Boundary-induced coherence in the staggered quantum walk on different topologies

    , Article Physical Review A ; Volume 98, Issue 1 , July , 2018 ; 24699926 (ISSN) Khatibi Moqadam, J ; Tayefeh Rezakhani, A ; Sharif University of Technology
    American Physical Society  2018
    Abstract
    The staggered quantum walk is a type of discrete-time quantum-walk model without a coin which can be generated on a graph using particular partitions of the graph nodes. We design Hamiltonians for potential realization of the staggered dynamics on a two-dimensional lattice composed of superconducting microwave resonators connected with tunable couplings. The naive generalization of the one-dimensional staggered dynamics generates two uncoupled one-dimensional quantum walks; thus more complex partitions need to be employed. However, by analyzing the coherence of the dynamics, we show that the quantumness of the evolution corresponding to two independent one-dimensional quantum walks can be... 

    Biodiesel production via transesterification of canola oil in the presence of Na–K doped CaO derived from calcined eggshell

    , Article Renewable Energy ; Volume 163 , 2021 , Pages 1626-1636 ; 09601481 (ISSN) Khatibi, M ; Khorasheh, F ; Larimi, A ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    CaO derived from calcined eggshell was doped with Na–K by wet impregnation method and the effect of different Na/K molar ratios was investigated on biodiesel production from canola oil. The catalysts were characterized by X-ray Powder Diffraction (XRD), Brunauer–Emmett–Teller (BET), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), and Thermogravimetric (TGA) analyses. FAME yields were determined by Gas Chromatography-Mass Spectrometry (GC-MS). The Na–K/CaO catalyst with Na/K molar ratio of 1 showed the highest FAME yield of 97.6% at optimum reaction conditions. Structural investigation of materials revealed that FAME yield was proportional to the number of basic sites on... 

    Aerodynamic Optimization of Axial Transonic Compressor Blade by Adjoint Method Using Bump/ Local Blowing

    , Ph.D. Dissertation Sharif University of Technology Khatibi Rad, Saeedeh (Author) ; Mazaheri, Karim (Supervisor)
    Abstract
    Transonic flow compressors are widely used today. In these systems, the occurrence of shock waves, interaction of the shock and the boundary layer, thickening of the boundary layer and separation are some challenges which can severely affect the aerodynamic performance. Here we use a numerical analysis and an optimization algorithm to optimize the aerodynamic shape of a transonic axial compressor blade section. The total pressure loss through a cascade of blade sections is selected as the cost function. A continuous adjoint optimization method is used along with a RANS solver to find the new blade section shape. Application of three different geometric modelling of a compressor blade section... 

    Mimicking the Hadamard discrete-time quantum walk with a time-independent Hamiltonian

    , Article Quantum Information Processing ; Volume 18, Issue 5 , 2019 ; 15700755 (ISSN) Khatibi Moqadam, J ; de Oliveira, M. C ; Sharif University of Technology
    Springer New York LLC  2019
    Abstract
    The discrete-time quantum walk dynamics can be generated by a time-dependent Hamiltonian, repeatedly switching between the coin and the shift generators. We change the model and consider the case where the Hamiltonian is time-independent, including both the coin and the shift terms in all times. The eigenvalues and the related Bloch vectors for the time-independent Hamiltonian are then compared with the corresponding quantities for the effective Hamiltonian generating the quantum walk dynamics. Restricted to the non-localized initial quantum walk states, we optimize the parameters in the time-independent Hamiltonian such that it generates a dynamics similar to the Hadamard quantum walk. We... 

    Design and Synthesis of a Drug Delivery System Based on Mesoporous Bioactive Glass

    , M.Sc. Thesis Sharif University of Technology Mirsafaie, Sahar Sadat (Author) ; Abdekhodaie, Mohammad Jafar (Supervisor)
    Abstract
    The aim of this research is to develop a smart mesoporous bioactive glass-based carrier for targeted drug delivery to cancer cells, particularly bone cancer cells. To achieve this, mesoporous bioactive glass nanoparticles were first synthesized, followed by surface modification with amine groups. To prevent premature drug release before reaching the target tissue and to introduce pH sensitivity, the nanoparticle pores were coated with oxidized hyaluronic acid via Schiff-base bonding with the amine groups on the surface. The use of hyaluronic acid facilitates active targeting of CD44 receptors, which are overexpressed on the surface of cancer cells compared to healthy cells. This process... 

    Electrodeposition of Pt nanostructures and its Application as Glucose Sensor

    , Ph.D. Dissertation Sharif University of Technology Mahshid, Sahar Sadat (Author) ; Dolati, Abolghasem (Supervisor) ; Ghorbani, Mohammad (Supervisor)
    Abstract
    The present work describes sensing application of modified Pt nanostructures towards detection of glucose. Modified Pt nanostructured electrodes were prepared using electrodeposition method such as chronoampermetry and potentiostatic pulse methods. The electrodeposition of Pt nanostructures was first studied by voltammetry and amperommetry techniques and then potentiostatic pulse method has been used to produce the alloyed structures of platinum. In this regard, the first electrode was proposed based on alloyed Pt/Ni nanowire arrays (NWAs) for the non-enzymatic detection of glucose. The Pt/Ni NWAs were prepared by pulse electrodeposition of Pt and Ni within a nano-pore polycarbonate (PC)... 

    Quantum Estimation of Open Systems Using Extended Cramer-Rao Bounds

    , M.Sc. Thesis Sharif University of Technology Mehboudi, Mohammad (Author) ; Rezakhani, Ali (Supervisor) ; Alipour, Sahar (Co-Advisor)
    Abstract
    Any physical system is characterized with some set of quantities or parameters, knowing which, is equivalent to estimation of the system. Evaluating such parameters is usually done using tomography methods. An important question to ask, is how to increase the precision of measurement, being able to do some specific set of physical operations, say, measurement?
    this question is more important in parameter estimation in quantum meanical systems. It has been shown that, quantum meanics causes a fundamental limit, on precision of estimating su parameters, escribed by the so called “antum Cramér-Rao bound”.We must note that almost all quantum meanical systems are interacting with the... 

    Production of Biodiesel Using Eggshell as Catalyst

    , M.Sc. Thesis Sharif University of Technology Khatibi, Maryam (Author) ; Khorasheh, Farhad (Supervisor) ; Larimi, Afsaneh Sadat (Supervisor)
    Abstract
    The aim of this project is to investigate and synthesize CaO-based nanocatalysts derived from chicken eggshell calcination with alkali metals and sodium-potassium compounds promoters used in the transesterification reaction of canola oil and methanol. Sections of this thesis include the synthesis of nanocatalysts, catalyst characterization tests, and investigation of reaction under optimal conditions. Two groups of catalysts containing different weight percentages of alkali metals based on CaO and 1 %wt sodium-potassium based on CaO with different weight percentages of these two elements were synthesized by wet impregnation method and used in the reaction under optimum condition. Catalyst... 

    Generation of transfer functions of subsystems using the test results of the whole system

    , Article Conference Proceedings of the Society for Experimental Mechanics Series, 9 February 2009 through 12 February 2009 ; 2009 ; 21915644 (ISSN) ; 9781605609614 (ISBN) Saadat Foumani, M ; Albooyeh, A. R ; Ashory, M. R ; Khatibi, M. M ; Sharif University of Technology
    2009
    Abstract
    This paper presents a new experimental-numerical method for deriving the transfer functions of a half-automobile model, containing: chassis, body, engine, engine mount and steering wheel, with five degrees of freedom. In this method different parts of system are not required to be disassembled from the main system and the transfer functions of subsystem are obtained through testing of the whole system. This method is based on the experimental results and does not need a mathematical model of the half-automobile. In this method, transfer functions of various parts of chassis are calculated through obtaining the response of secondary elements mounted on the chassis to the displacement input... 

    Selective Transfection of Smart Polymeric Nanoparticles Into Reactive Astrocytes in Animal Model of Spinal Cord Injury

    , Ph.D. Dissertation Sharif University of Technology Sabourian, Parinaz (Author) ; Frounchi, Masoud (Supervisor) ; Mashayekhan, Shohreh (Co-Supervisor) ; Kiani, Sahar (Co-Supervisor)
    Abstract
    In this study, chitosan-based nanoparticles were prepared due to their biocompatibility, availability, high loading capacity of drug, stimulus responsive behavior and the presence of active functional groups. Chitosan was chemically functionalized with reactive oxygen species (ROS)-responsive moiety to respond to the oxidative stess and endosomal pH in nerve injuries. To prepare nanoparticles, functinalized chitosan ionically gelated with pH-responsive polyanions with ROS-scavenging properties such as polyacrylic acid and hyaluronic acid. Then, pH- and ROS-responsive nanoparticles were used for selective transfection into reactive astrocytes and axonal regeneration in spinal cord injuries.... 

    Nanogold imprinted starch bionanocomposites for food packaging applications

    , Article Starch Based Nanomaterials for Food Packaging: Perspectives and Future Prospectus ; 2023 , Pages 209-226 ; 978-044318967-8 (ISBN); 978-044318968-5 (ISBN) Tariq, T ; Saleem, I. M ; Sahar, A ; Raza, N ; Sameen, A ; Nayik, G. A ; Ramniwas, S ; Sharif University of Technology
    Elsevier  2023
    Abstract
    Food science researchers are concerned about global food wastage due to decreased shelf life. It has been shown that using approaches based on nanotechnology, including metal-based nanoparticles (NPs), can alleviate the issues with decreased shelf life and environmental problems. Gold nanoparticles (AuNPs) and their synthesis have seen notable advancements in the last several decades. AuNPs are now utilised more often in industrial and medicinal settings. AuNPs are being employed in the nanopackaging industry as a recently adopted technique because of their medicinal and antibacterial properties and their inert and hypoallergenic nature. When employed in the food industry, AuNPs have...