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Smart micro/nano-robotic systems for gene delivery
, Article Current Gene Therapy ; Volume 17, Issue 2 , 2017 , Pages 73-79 ; 15665232 (ISSN) ; Nejat Pishkenari, H ; Sharif University of Technology
Bentham Science Publishers B.V
2017
Abstract
Background: Small scale robotics have attracted growing attention for the prospect of targeting and accessing cell-sized sites, necessary for high precision biomedical applications and drug/gene delivery. The loss of controlled gene therapy, inducing systemic side effects and reduced therapeutic efficiency, can be settled utilizing these intelligent carriers. Methods: Newly proposed solutions for the main challenges of control, power supplying, gene release and final carrier extraction/degradation have shifted these smart miniature robots to the point of being employed for practical applications of transferring oligonucleotides (pDNA, siRNA, mRNA, etc.) in near future. Conclusion: In this...
The Status of Scientific-Technological Instruments from the Point of View of Scientific Anti-Realism
, M.Sc. Thesis Sharif University of Technology ; Akbari, Javad (Supervisor)
Abstract
One of the main arguments between scientific realists and scientific anti-realists is about observability. As a prominent anti-realist, van Fraassen and his theory of constructive empiricism and his views on observability and the use of scientific instruments, have been the subject of many debates. He believes that observation is the sole path to knowledge and observation is only possible through unaided human eye, so seeing through scientific instruments like microscopes does not count as observation, therefore the information gained from these procedures are not necessarily true.This thesis not only examines van Fraassen’s outlooks on the matter, but also examines his opponents’ view and...
A Fabrication Method of Neutrally-buoyant Magnetic Micro-robot to Improve Its Motion Control
, M.Sc. Thesis Sharif University of Technology ; Nejat Pishkenari, Hossein (Supervisor)
Abstract
Micro-robotics is one of the currently emerging technologies which has attracted attentions for its probable applications in different fields including biotechnology, diagnosis and treatment in medical engineering as well as general studies in micro-scale science and engineering. Magnetic micro-robotics is considered as the most promising group, primarily due to the biocompatibility of magnetic fields and advances in electronic circuits to produce and control such fields. One critical point in utilizing these robots is their high density in comparison with the working fluid and their tendency to sink. In this thesis, a method to fabricate buoyant magnetic robots has been proposed based on...
Optimal controller design for 3D manipulation of buoyant magnetic microrobots via constrained linear quadratic regulation approach
, Article Journal of Micro-Bio Robotics ; Volume 15, Issue 2 , 2019 , Pages 105-117 ; 21946418 (ISSN) ; Nejat Pishkenari, H ; Sitti, M ; Sharif University of Technology
Springer
2019
Abstract
We consider magnetic actuation and control of a spherical neutrally buoyant magnetic microrobot via magnetic coil setups and seek to design an optimal controller to reduce the required energy and coils’ currents. We showed that in currently employed setups, where the actuation frequency is few tens of Hertz, the nonlinear dynamics of the system can be well approximated by a set of linear constrained ones. The approximated model is obtained by consciously overlooking the rotational dynamics and the inertia terms in translational dynamics. We acquired the linear quadratic regulation (LQR) controller for the approximated model which is a constrained time-varying system. Finally, 3D manipulation...
On the hysteretic behavior of trapezoidally corrugated steel shear walls
, Article Structural Design of Tall and Special Buildings ; Vol. 23, Issue. 2 , 10 February , 2014 , pp. 94-104 ; ISSN: 15417794 ; Mofid, M ; Sharif University of Technology
2014
Abstract
At present, corrugated plates have numerous applications such as web of plate girders and aerospace applications. Higher out-of-plane stiffness and initial elastic strength of the corrugated plates compared with flat plates are reasons for consideration. This study investigates the behavior of trapezoidally corrugated steel plate shear walls (TCSPSWs) under monotonic and cyclic loadings. Finite element analyses that include both material and geometric nonlinearities are employed for the examination. The results from finite element analysis are verified through tested specimen findings. Moreover, the behavior of the steel shear walls with the flat infill panels and the corrugated plate infill...
Cyclic test of steel plate shear wall designed by PFI method
, Article Advanced Materials Research ; Volume 378-379 , 2012 , Pages 785-788 ; 10226680 (ISSN) ; 9783037852880 (ISBN) ; Mofid, M ; Sharif University of Technology
2012
Abstract
In this paper, Plate Frame Interaction (PFI) developed by other researches for modeling Steel Plate Shear Wall (SPSW) is applied for designing a half-scale, single bay and one story SPSW. After designing of SPSW, one specimen is constructed accordingly. In order to determine the mechanical properties of steel, coupon test is performed; and then again theoretical relations based on PFI is re-checked. In this study, gravity loads are neglected and only seismic resistance of SPSW is considered. With cyclic lateral loading as quasi-static load, according to Acceptance Criteria for Cyclic Racking Shear Tests For Metal-Sheathed Shear Walls with Steel Framing (AC154) and obtaining its hysteretic...
Comparison of beam shapes and transmission powers of two prism ducts
, Article Australian Journal of Basic and Applied Sciences ; Volume 4, Issue 10 , 2010 , Pages 4922-4929 ; 19918178 (ISSN) ; Golnabi, H ; Sharif University of Technology
2010
Abstract
Design and performance of two-stage optical beam shaping system based on a plastic fiberbundle, prism coupled waveguide, is described in this study. Such systems offer practical means to modify and change the output beam shape at two stages and also provide quantitative information concerning the output beam intensity. It is possible to investigate output power and image transmittance data by using a light source for illumination and image analysis by a CCD/digital camera. The photograph picture of the illuminating LED beam shows a circular shape with a diameter of about 10 mm at its output point. Picture of the fiber-bundle output beam is also taken, which shows a rectangular shape with a...
On the improvement of steel plate shear wall behavior using energy absorbent element
, Article Scientia Iranica ; Volume 24, Issue 1 , 2017 , Pages 11-18 ; 10263098 (ISSN) ; Mofid, M ; Sharif University of Technology
Sharif University of Technology
2017
Abstract
Structural engineers have recognized unstiffened Steel Plate Shear Wall (SPSW) as an economical lateral resisting system due to the post-buckling capacity, energy dissipation, and deformability. This study investigates practical application of an added Energy Absorbent Element (EAE), subjoined to the SPSW in order to improve seismic behavior of the SPSW. The EAE is an aluminum shear panel with or without bracings and surrounding frame. Furthermore, a series of parametric studies are implemented to examine the effect of dimensions, position, and formation of the EAE. It is assumed that the lateral loading is applied as quasi-static loading. Further, nonlinearity of the material and the...
Intelligent trajectory tracking of an aircraft in the presence of internal and external disturbances
, Article International Journal of Robust and Nonlinear Control ; Volume 29, Issue 16 , 2019 , Pages 5820-5844 ; 10498923 (ISSN) ; Banazadeh, A ; Sharif University of Technology
John Wiley and Sons Ltd
2019
Abstract
This research deals with developing an intelligent trajectory tracking control approach for an aircraft in the presence of internal and external disturbances. Internal disturbances including actuators faults, unmodeled dynamics, and model uncertainties as well as the external disturbances such as wind turbulence significantly affect the performance of the common trajectory tracking control approaches. There are several fault-tolerant control approaches in the literature to overcome the effects of specific actuator or sensor faults during the flight. However, trajectory tracking control of an air vehicle in the presence of unexpected faults and simultaneous presence of wind turbulence is...
Online identification of aircraft dynamics in the presence of actuator faults
, Article Journal of Intelligent and Robotic Systems: Theory and Applications ; Volume 96, Issue 3-4 , 2019 , Pages 541-553 ; 09210296 (ISSN) ; Banazadeh, A ; Sharif University of Technology
Springer
2019
Abstract
In this paper, a multiple model-based nonlinear identification approach is introduced for a conventional aircraft in the presence of different types of actuator faults. Occurrence of actuator faults can obviously reduce the validity of a predetermined dynamic model of nonlinear systems. In such cases, use of multi-model structures can be an effective choice. However, determining the optimal validity functions of the local models in a multi-model structure is still a challenging problem. This problem becomes even more challenging in case of unpredictable faults, which are not considered in training the local models. In this paper, two effective techniques are proposed for online determination...
Thermodynamic Analysis of the Temporal Changes in Salt Concentration in Saline Lakes (the case of Urmia lake)
, M.Sc. Thesis Sharif University of Technology ; Tajrishi, Masoud (Supervisor)
Abstract
Urmia Lake is a strong electrolyte containing various salts, with a thermodynamic identity. Changes in the temperature and volume of lake water cause a change in the concentration of ions in this brine as well as the composition and precipitation of salts in the lake. As a result of these changes, the thermodynamic properties of brine are also changed. The purpose of this study was to investigate the effect of mixing the rivers entering the lake and calculate and analyze the changes in the quality and hydrogeochemical characteristics of Urmia Lake and the amount of precipitation and dissolution of the main minerals in Urmia Lake during the period of 2007-2013 per month. For this purpose,...
Linear multi-variable control technique for smart power management of wind turbines
, Article 2012 International Conference onAdvanced Mechatronic Systems, ICAMechS 2012 ; 2012 , Pages 559-564 ; 9780955529382 (ISBN) ; Banazadeh, A ; Sharif University of Technology
2012
Abstract
Variable speed wind turbines are widely used in the modern power industry. These turbines that are usually driven by doubly fed induction generators (DFIG) contain two groups of controlling variables; mechanical variables like pitch angle, and electrical variables like rotor voltage. During the turbine operation, with variable wind speed, power must be managed in two different regimes; power optimization and power limitation. In the current research, initially a non-linear simulation, based on the general wind turbine dynamic model is presented. Then, the desired controllers for both pitch angle and generator voltage components are constructed. To validate turbine behavior and controller...
Robustness investigation of the linear multi-variable control technique for power management of DFIG wind turbines
, Article International Journal of Advanced Mechatronic Systems ; Volume 5, Issue 1 , 2013 , Pages 37-46 ; 17568412 (ISSN) ; Banazadeh, A ; Sharif University of Technology
2013
Abstract
Variable speed wind turbines are widely used in the modern power industry. These turbines that are usually driven by doubly fed induction generators (DFIGs) contain two groups of controlling variables; mechanical variables like pitch angle and electrical variables like rotor voltage. During the turbine operation, with variable wind velocity, power must be managed in two regimes; power optimisation and power limitation. In the current research, initially a non-linear simulation, based on the general wind turbine dynamic model is presented. Then, the desired controllers for both pitch angle and generator voltage components are constructed. After designing the controller, in order to...
Robustness investigation of a ducted-fan aerial vehicle control, using linear, adaptive, and model predictive controllers
, Article International Journal of Advanced Mechatronic Systems ; Volume 6, Issue 2-3 , 2015 , Pages 108-117 ; 17568412 (ISSN) ; Banazadeh, A ; Sharif University of Technology
Inderscience Publishers
2015
Abstract
A comparison of three common controllers for stabilising a vertical take-off and landing air vehicle is presented. RMIT is a small sized tail-sitter ducted fan air vehicle with a particular configuration layout, multiple control surfaces, low weight, and high-speed flight capability. The main problem here is control effectiveness at low flight speeds and transition manoeuvres because of the inherent instability. In the current study, a comprehensive nonlinear model is firstly developed for RMIT, followed by a validation process. Subsequently, linear, adaptive and model predictive controllers are designed in vertical flight. Based on the simulation results, it is shown that the linear...
Adaptive model predictive control-based attitude and trajectory tracking of a VTOL aircraft
, Article IET Control Theory and Applications ; Volume 12, Issue 15 , 2018 , Pages 2031-2042 ; 17518644 (ISSN) ; Rezaeizadeh, A ; Sharif University of Technology
Institution of Engineering and Technology
2018
Abstract
A novel adaptive model-based predictive controller for attitude and trajectory tracking of a vertical take-off and landing(VTOL) aircraft in the simultaneous presence of model uncertainties and external disturbances is introduced in this study. Animportant challenge of designing the model-based controllers is developing an accurate model, especially in the presence ofmodel uncertainties. In this study, first, the nominal model of a ducted-fan air vehicle, which is a multi-input multi-outputnonlinear system with non-minimum phase behaviour, is given as the test case of this research. After that, two modified robustand adaptive model predictive controllers are proposed for tracking a...
Multimodel ELM-based identification of an aircraft dynamics in the entire flight envelope
, Article IEEE Transactions on Aerospace and Electronic Systems ; Volume 55, Issue 5 , 2019 , Pages 2181-2194 ; 00189251 (ISSN) ; Roudbari, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
The development of a multiple model-based identification algorithm is addressed in this paper for nonlinear modeling of a conventional aircraft in the entire flight envelope. The dynamic model of an aircraft varies significantly depending on changes in the flight condition of the air vehicle including the altitude and the equivalent air speed. Therefore, the conventional identification approaches for generating a single nonlinear model with time-invariant parameters cannot be used in the entire flight envelope of an aircraft. Accordingly, a multiple model-based approach using nonlinear autoregressive exogenous neural networks is introduced in this paper as a powerful tool in identifying...
Fault-tolerant predictive trajectory tracking of an air vehicle based on acceleration control
, Article IET Control Theory and Applications ; Volume 14, Issue 5 , 2020 , Pages 750-762 ; Banazadeh, A ; Sharif University of Technology
Institution of Engineering and Technology
2020
Abstract
A novel fault-tolerant model predictive control (MPC)-based trajectory tracking approach for an aerial vehicle is presented in this study. A generalised online sequential extreme learning machine is introduced first to identify the corresponding coefficients of actuator faults. Subsequently, a robust trajectory tracking control is developed based on MPC, where the system constraints can be effectively considered in the designed control scheme. Trajectory tracking control is achieved by controlling only the acceleration of the aerial robot in the MPC structure. This leads to less computational burden and faster closed-loop dynamics. In addition, an effective disturbance observer is employed,...
Simultaneous trajectory tracking and aerial manipulation using a multi-stage model predictive control
, Article Aerospace Science and Technology ; Volume 112 , 2021 ; 12709638 (ISSN) ; Banazadeh, A ; Sharif University of Technology
Elsevier Masson s.r.l
2021
Abstract
With the exception of a few works, the current approaches to aerial manipulation control do not typically consider the system constraints in the control design process. Also, the issue of closed-loop stability in the presence of system constraints is not thoroughly analyzed. In this paper, a novel multi-stage model predictive control (MPC)-based approach for aerial manipulation is proposed to ensure the closed-loop stability in the presence of model uncertainties and external disturbances, while satisfying the operational constraints. The detailed nonlinear model of a general aerial manipulator, consisting of a quadrotor equipped with a 3 degrees of freedom manipulator, is first developed...
Synthesis of Dextran-MA-Gly-Gly-NHNH2 Copolymer as a Possible Biodegradable and pH-responsive Carrier for Doxorubicin
, M.Sc. Thesis Sharif University of Technology ; Pourjavadi, Ali (Supervisor)
Abstract
Some chemotherapy drugs have unpleasant side effects and use them due to the instability and low solubility in blood flow is associated with problems and limitations.To solve these problems, controlled drug delivery systems have been proposed. In this process, the polymer increased solubility, stability and low toxicity and the active drug realease in a particular tissue or controlled speed. Therefore be less adverse side effects. Dextran is the one of biocompatible and water-soluble polysaccharides that due to its unique characteristics, widely used as carriers in drug delivery. Dextran molecules can bind to drugs and increased solubility, stability, and reduce their side effects....
A physicochemical evaluation of modified HZSM-5 catalyst utilized for production of dimethyl ether from methanol
, Article Petroleum Science and Technology ; Vol. 32, issue. 8 , Feb , 2014 , pp. 904-911 ; ISSN: 10916466 ; Kazemeini, M ; Fattahi, M ; Amjadian, A ; Sharif University of Technology
2014
Abstract
A number of HZSM-5 catalysts modified with 5 wt% Mg, Na, Zr, and Al as well as others modified with 5-60 wt% Zn prepared by wet impregnation. These materials were characterized by the NH3-TPD, XRF, and XRD analyses and tested in a slurry reactor to determine their activities in dehydration of methanol solution in kerosene. Reactions were carried out at 230°C and 19 bar for 4 h of residence time in the reactor. Results showed that in the first series, the catalyst modified with Zr and in the second series, the one modified with 10 wt% Zn led to the highest methanol conversion. It was deduced that elimination of strong acid sites and partial replacement of active cations in the HZSM-5 zeolite...