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aghajanzadeh--meisam
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Nonlinear Dynamic Analysis of Concrete Gravity Dam by Considering Elasto-Plastic Behavior for Foundation
, M.Sc. Thesis Sharif University of Technology ; Ghaemian, Mohsen (Supervisor)
Abstract
Concrete dams are important nations infra structures. They store water for different purposes such as irrigation, water supply, flood control, electric power, recreation and improvement of navigation. Safety of concrete dams is a major challenge for the owners. As a result, concrete dam’s behavior when subjected to different load condition especially an earthquake ground motion is a concern which may cause some damage. It is needed to determine concrete gravity dam’s response under different load condition. One of the important factors for determining concrete dam’s response is foundation properties and its behavior under seismic loading. A finite element model consisting of...
Nonlinear dynamic analysis of a concrete gravity dam considering an elastoplastic constitutive model for the foundation
, Article Scientia Iranica ; Volume 20, Issue 6 , 2013 , Pages 1676-1684 ; 10263098 (ISSN) ; Ghaemian, M ; Sharif University of Technology
Sharif University of Technology
2013
Abstract
Dam failure can result in a catastrophic break followed by a ood wave, often with considerable loss of life or property. One of the main causes of dam failure is loss of shear strength and the existence of discontinuity within the foundation. Dynamic analysis of concrete dams usually considered concrete behavior to be nonlinear and the foundation rock is assumed to be linear. In this study, seismic analysis of a concrete gravity dam was conducted to investigate the effect of the foundation on the nonlinear response. A finite element model of a dam-reservoir-foundation was considered to properly model the foundation as well as dam body nonlinear behaviors. An elasto-plastic formulation was...
Nonlinear Adaptive Control of Treatment in a Basic Hepatitis B Virus Infection Model in the Presence of Uncertainties
, M.Sc. Thesis Sharif University of Technology ; Zohour, Hassan (Supervisor)
Abstract
Hepatitis B is an infectious disease caused by the hepatitis B virus (HBV) which affects the liver. Several dynamic models have been developed to mathematically describe the HBV infection and antiviral therapy. In this thesis, a nonlinear adaptive control strategy is developed for the treatment of the Hepatitis B Virus (HBV) infection inside a body. The considered nonlinear HBV model has three state variables, the numbers of uninfected and infected cells and free viruses. The proposed control law is designed for the antiviral drug input such that the number of free viruses per unit volume of the blood and consequently the number of infected cells decrease to some desired values. The...
Heidegger on Science and Tool (Emphasized on "Being and Time")
,
M.Sc. Thesis
Sharif University of Technology
;
Sefidkhosh, Meisam
(Supervisor)
;
Taghavi, Mostafa
(Co-Advisor)
Abstract
This thesis is going to investigate the ontological foundation of Science and Tool. To this aim, it refers to Heidegger’s works especially the Being and time. Heidegger gets involve in analyzing Science in the Being and Time. He emphasizes on importance of establishment of a fundamental knowledge which should ontologically recognize basic concepts and methods of Sciences, to cause a real progress in sciences. Heidegger also asserts that the Mathematical interpretation of the world is not a fundamental, and it must be replaced with phenomenological interpretation, which clarifies the ontological foundation of the theoretical view, and regards to all aspects of world’s existence. In this...
Kierkegaardian Faith: On The Subject of Faith and Her Hope
, M.Sc. Thesis Sharif University of Technology ; Sefidkhoh, Meisam (Supervisor) ; Azadegan, Ebrahim (Supervisor)
Abstract
In this treatise, it will be shown that the subject of faith is the subject who loves God and in showing her love to God, she sacrifices her dearest things in the world. By doing that, she would free herself from everything that mind herself. She doesn’t do this action to be given a better reward by God. Her motivation for performing this action is nothing but love. Meanwhile, the subject of faith hopes God to respond to her love and engage in an I-Thou relationship with her. Now, her hope would be justified when God plays an active role in the world and admires her action, i.e., when eros can be attributed to God
Robust control strategy for HBV treatment: Considering parametric and nonparametric uncertainties
, Article Control Applications for Biomedical Engineering Systems ; 2020 , Pages 127-147 ; Sharifi, M ; Falsafi, A ; Sharif University of Technology
Elsevier Inc
2020
Abstract
Hepatitis is one of the most perilous viral infectious diseases and many people suffer from it all around the world. In particular, hepatitis B is a terribly dangerous disease which may cause severe liver damage or cancer if it is not treated. Recently, several dynamic models have been developed from experimental studies for describing such diseases mathematically. The certainty of these dynamics models is questionable in realistic treatment processes. Thus, the modeling uncertainties should be considered in the dynamics, which necessitates employing robust control strategies capable to overcome these uncertainties. Accordingly, in this research, a control strategy is developed in order to...
Foundation material nonlinearity in dam-reservoir-massed foundation coupled problems
, Article Ingegneria Sismica ; Volume 34, Issue 4 , 2017 , Pages 1-28 ; 03931420 (ISSN) ; Mirzabozorg, H ; Ghaemian, M ; Sharif University of Technology
2017
Abstract
In the present paper, the nonlinear seismic behavior of a concrete gravity damreservoir- massed foundation system is studied focusing on the foundation material nonlinearity. For this purpose, a finite element program utilizing the elasto-plastic formulation for the foundation medium is provided considering the tensile and shear failure modes. Hoek-Brown and Mohr Coulomb criteria are used as the yield and plastic potential function of the shear failure mode, respectively; and in the tensile failure mode, various levels of the tensile strength are applied to the foundation. Bearing capacity is studied considering the localized plastic elements and forming the sliding path by plastic elements...
Study of Dispersed Phase Holdup and Slip Velocity in a Pulsed Disc and Doughnut Extraction Column
, M.Sc. Thesis Sharif University of Technology ; Outukesh, Mohammad (Supervisor) ; Torab Mostaedi, Meisam (Supervisor)
Abstract
Dispersed phase holdup has been measured in a 75 mm diameter pulsed disc and doughnut extraction column for three different liquid-liquid systems. The effects of operational variables such as pulsation intensity and dispersed and continuous phases flow rates on holdup have been investigated and found to be significant. The existence of three different operational regimes, namely mixer-settler, dispersion, and emulsion regimes, was observed when the energy input was changed. The results indicated that the characteristic velocity approach is applicable to this type of extraction column for analysis holdup in transition and emulsion regions. Empirical correlations are derived for prediction of...
Investigation of Equilibrium and Kinetics of Uranium Solvent Extaction by Cyanex 301 Using a Single Drop Column
, M.Sc. Thesis Sharif University of Technology ; Samadfam, Mohammad (Supervisor) ; Torab-Mostaedi, Meisam (Supervisor)
Abstract
Uranium separation from other metals in ore and nuclear waste is one of the most important stagesin nuclear fuel cycling. Solvent extraction is the common method for uranium extraction that reagent plays important rule in this technique. In this investigation, uranium solvent extraction is carried out by Cyanex 301 as reagent from nitric acid. At beginning, equilibrium batch extraction was carried and the effect of parameters such as pH, reagent concentration, temperature, shaking time of two phases, volumetric ratio of two phases, diluent and nitric acid concentration on extraction was investigated and optimum value of parameters was calculated. Uranium concentration effect was also...
Robust adaptive Lyapunov-based control of hepatitis B infection
, Article IET Systems Biology ; Volume 12, Issue 2 , April , 2018 , Pages 62-67 ; 17518849 (ISSN) ; Sharifi, M ; Tashakori, S ; Zohoor, H ; Sharif University of Technology
Institution of Engineering and Technology
2018
Abstract
A new robust adaptive controller is developed for the control of the hepatitis B virus (HBV) infection inside the body. The non-linear HBV model has three state variables: uninfected cells, infected cells and free viruses. A control law is designed for the antiviral therapy such that the volume of infected cells and the volume of free viruses are decreased to their desired values which are zero. One control input represents the efficiency of drug therapy in inhibiting viral production and the other control input represents the efficiency of drug therapy in blocking new infection. The proposed controller ensures the stability and robust performance in the presence of parametric and...
An investigation on the effects of gas pressure drop in heat exchangers on dynamics of a free piston stirling engine
, Article International Journal of Engineering, Transactions B: Applications ; Volume 30, Issue 2 , 2017 , Pages 1243-1252 ; 1728144X (ISSN) ; Tavakolpour Saleh, A. R ; Aghajanzadeh, O ; Sharif University of Technology
Materials and Energy Research Center
2017
Abstract
This paper is devoted to study the effects of pressure drop in heat exchangers on the dynamics of a free piston Stirling engine. First, the dynamic equations governing the pistons as well as the gas pressure equations for hot and cold spaces of the engine are extracted. Then, by substituting the obtained pressure equations into the dynamic relationships the final nonlinear dynamic equations governing the free piston Stirling engine are acquired. Next, effects of the gas pressure drop in heat exchangers on maximum strokes of the pistons and their velocities and accelerations are investigated. Furthermore, influences of pressure drop increase in the heat exchangers on maximum and minimum gas...
Nonlinear adaptive control method for treatment of uncertain hepatitis B virus infection
, Article Biomedical Signal Processing and Control ; Volume 38 , 2017 , Pages 174-181 ; 17468094 (ISSN) ; Sharifi, M ; Tashakori, S ; Zohoor, H ; Sharif University of Technology
2017
Abstract
In this paper, a nonlinear adaptive control method is presented for the treatment of the Hepatitis B Virus (HBV) infection. Nonlinear dynamics of the HBV, modeling uncertainties and three state variables (the numbers of uninfected and infected cells and free viruses) are taken into account. The proposed control law is designed for the antiviral drug input such that the number of free viruses and consequently the number of infected cells decrease to the desired values. An adaptation law is also presented to overcome modeling uncertainties by updating estimations of the system parameters during the treatment period. The stability of the process and convergence to desired state values are...
Synthesis of CaO Impregnated on Carbon Nano Tube for Biodiesel Production
, M.Sc. Thesis Sharif University of Technology ; Khorashe, Farhad (Supervisor) ; Tabatabaei, Meisam (Supervisor) ; Rashidi, Alimorad (Supervisor)
Abstract
In the current work, jatropha oil was studied in the hetrogenious solid catalytic transesterfication reaction. For this perpous, KOH/CNT catalyst which was prepared by dry impregnation method was used. SEM, XRD and TGA were applied for the catalyst characterization. The results showed that for the KOH/CNT catalyst, by increasing the loading of KOH, the activity of the catalyst increased and the most active catalyst was prepared by 20% loading of KOH. The optimum conditions for transesterfication reaction in the percense of this catalyst were: 4.7% catalyst weigth and the 24.5 molar ratio of methanol to oil and also the reaction time of 2 houres which the rate of reaction at this time is...
Multistage decoding for an internally coded fibre-optic time-hopping/optical code division multiple access communication system
, Article IET Communications ; Volume 3, Issue 4 , 2009 , Pages 655-665 ; 17518628 (ISSN) ; Nasiri Kenari, M ; Tabataba, F. S ; Aghajanzadeh, S. M ; Sharif University of Technology
2009
Abstract
A multistage decoder for the internally convolutionally coded fibre-optic time-hopping code division multiple access system recently introduced is considered. In this system, the decoder consists of several stages. The first stage is implemented using one of the single-user decoders introduced. The following stages are maximum likelihood (ML) decoders each of which use the decisions made by the previous stage. The performance of the proposed decoder is evaluated by a Monte Carlo simulation. Numerical results show that a multistage decoder with only two stages greatly outperforms the single-stage decoder with negligible increase in complexity. The authors also derive the Chernoff bound for...
Preparation of metal–organic frameworks UiO-66 for adsorptive removal of methotrexate from aqueous solution
, Article Journal of Inorganic and Organometallic Polymers and Materials ; 2017 , Pages 1-10 ; 15741443 (ISSN) ; Zamani, M ; Molavi, H ; Khieri Manjili, H ; Danafar, H ; Shojaei, A ; Sharif University of Technology
2017
Abstract
A low cytotoxic metal–organic framework (MOF) UiO-66 (UiO stands for University of Oslo) and NH2-UiO-66, that showed high cell viability of HFF-2 via 3-(4, 5-dimethylthiazol-2-yl) 2, 5-diphenyl tetrazolium assay, was reported as an effective adsorbent (antidotal) agents. The structure of MOFs was confirmed by Fourier transform infrared, Field emission scanning electron microscopy (FESEM) and X-ray diffraction. Thermal behavior of MOFs was investigated using with thermogravimetric analyzer in nitrogen atmosphere to check the thermal stability. FESEM showed NH2-UiO-66 displayed symmetrical crystals with triangular base pyramid morphology, with the particle size around 100 nm and uniform size...
Evaluation of UiO-66 metal organic framework as an effective sorbent for curcumin's overdose
, Article Applied Organometallic Chemistry ; Volume 32, Issue 4 , 2018 ; 02682605 (ISSN) ; Zamani, M ; Aghajanzadeh, M ; Kheiri Manjili, H ; Danafar, H ; Shojaei, A ; Sharif University of Technology
John Wiley and Sons Ltd
2018
Abstract
Metal organic frameworks (MOFs) UiO-66 (UiO stands for University of Oslo) and NH2-UiO-66 were prepared and characterized as sorbent (antidotal agents) for curcumin (CUR) adsorption. The structure of products were characterized by X-ray powder diffraction (XRD), Field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), Attenuated Total Reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and N2 adsorption–desorption measurements. FESEM showed NH2-UiO-66 displayed symmetrical crystals with triangular base pyramid morphology, with the particle size around 100 nm and uniform size distribution. Adsorption capacities of CUR/MOFs with different mass ratios...
Preparation of metal–organic frameworks uio-66 for adsorptive removal of methotrexate from aqueous solution
, Article Journal of Inorganic and Organometallic Polymers and Materials ; Volume 28, Issue 1 , 2018 , Pages 177-186 ; 15741443 (ISSN) ; Zamani, M ; Molavi, H ; Khieri Manjili, H ; Danafar, H ; Shojaei, A ; Sharif University of Technology
Springer New York LLC
2018
Abstract
A low cytotoxic metal–organic framework (MOF) UiO-66 (UiO stands for University of Oslo) and NH2-UiO-66, that showed high cell viability of HFF-2 via 3-(4, 5-dimethylthiazol-2-yl) 2, 5-diphenyl tetrazolium assay, was reported as an effective adsorbent (antidotal) agents. The structure of MOFs was confirmed by Fourier transform infrared, Field emission scanning electron microscopy (FESEM) and X-ray diffraction. Thermal behavior of MOFs was investigated using with thermogravimetric analyzer in nitrogen atmosphere to check the thermal stability. FESEM showed NH2-UiO-66 displayed symmetrical crystals with triangular base pyramid morphology, with the particle size around 100 nm and uniform size...