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bazyar-shourabi--neda
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Modeling and control of HIV by computational intelligence techniques
, Article IFMBE Proceedings, 30 April 2010 through 2 May 2010, College Park, MD ; Volume 32 IFMBE , April , 2010 , Pages 192-195 ; 16800737 (ISSN) ; 9783642149979 (ISBN) ; Sharif University of Technology
2010
Abstract
The paper aims at proposing a controller through two-layer neural networks (NN) in order to control CD4 amount in HIV + Patients. In the same direction, initially a new mathematical model by using of two-layer neural networks (NN) was designed. Medical information of 300 HIV + Patients who were being treated in the Iranian Research Center for HIV/AIDS (IRCHA), Imam Khomeini Hospital, Tehran, was used to design this model. Highly active antiretroviral therapy (HAART) medical method is a significant method that was used in this study. It is worthy to say that CD4 amount declining leads to immune system deficiency and it is considered as one of AIDS main symptoms. Output of this mathematic...
Modeling & Control of HIV by Computational Intelligence Techniques
, M.Sc. Thesis Sharif University of Technology ; Kazemzadeh Hannani, Siamk (Supervisor) ; Seyfipour, Navid (Supervisor)
Abstract
An event must be modeled in a way that either reflects a comprehensive perspective for the event or acts in an especial part of that event, roperly. The main aim of this thesis is to control. Therefore the models will be accepted whenever the suggested mathematical models can move towards controller final target, desirably.This thesis proposes a linear mathematical model, five nonlinear models and a simple model based upon Convolution, Fuzzy Regression and Neural Networks techniques for Acquired Immune Deficiency Syndrome (AIDS), respectively. The proposed models were achieved through studying 300 HIV+ Patients who were under Highly Active Antiretroviral Therapy (HAART) approach in Iranian...
Machine Learning-Based Rapid Visual Screening of Buildings for Potential Seismic Damage Using BuildingImages
, M.Sc. Thesis Sharif University of Technology ; Bakhshi, Ali (Supervisor)
Abstract
Rapid visual screening is a way to assess unsafe structures and reduce urban earthquake vulnerability. Although this method is faster than detailed analytical methods(e.g. Incremental dynamic analysis), it still requires a lot of time and financial resources to execute. Due to the widespread use of computer vision in engineering, this study has used this technology to perform rapid visual screening, improve its overall process and provide a standard method for automatic assessment of structures. In the process of rapid visual screening, the screener identifies features from the exterior view of the building, which are finally recorded in a scoring system. According to the score obtained,...
Design and Fabrication of Functionally Graded TPMS Sandwich Panel Core for Enhancing Energy Absorption Capability by Vat Photopolymerization
, M.Sc. Thesis Sharif University of Technology ;
Abstract
To create gradient structures for TPMS metamaterials, various patterns such as longitudinal, radial, and spherical gradient structures can be utilized. Limited studies have compared the failure patterns and energy absorption of these structures. This research aims to present a suitable gradient pattern to enhance the energy absorption of sandwich panels with a porous TPMS metamaterial core by examining the effects of previous patterns on the mechanical behavior of the structure under compressive loads. In the initial phase of the study, the behavior of different gradient patterns of the TPMS structure with a Schwartz unit cell was investigated through longitudinal, radial, and spherical...
The Effect of Second Order Dissipation on the Sound Velocity in Quasi-QCD Plasma Using the Effective Potential of the Linear Sigma Model
, M.Sc. Thesis Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
The heavy ion collision experiments are in progress in order to investigate how the Universe has evolved after the Big Bang. The recent observations show that a nearly perfect fluid is produced after heavy ion collisions. An appropriate incorporation of the relativistic hydrodynamics and the field theory would help us to describe the dynamics of QCD (Quantum Chromodynamics) matter under extreme conditions, and to survey the expected phase transitions. The majority of efforts to investigate the characteristics of the QCD plasma are devoted to an ideal, non-dissipative one. To get the results which are highly in accordance with the experiment, it is necessary to bring also in mind the role of...
Effect of the Fluctuations of Quantum Chromodynamics Topological Charge on the Dispersion Relation of NJL Model
, M.Sc. Thesis Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
One of the long-lived problems in the theory of quantum chromo dynamics is the violation of parity (P) and charge-parity (CP) symmetries in strong interactions. The existence of gluon configurations sourcing from topology leads to degeneracy in the vacuum structure of the theory. This phenomenon is realized by the addition of an extra term proportional to the parameter to QCD Lagrangian. Experimental estimates of neutron electric dipole, predicts a very small value for this parameter. There is no verified justification for this discrepancy. Recently at the relativistic heavy ion collider laboratory (RHIC) some experimental evidence has been found which indicates local CP violation in...
The Kinetic Term of the Effective Action in the NJL Model in Background Magnetic Field at Finite Temperature and Chemical Potential
, M.Sc. Thesis Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
Kinetic terms of effective action including derivative of classical field become significant, when we have a dynamical field.These terms have been calculated as a function of the fermionic propagator in NJL model, which is an effective model of QCD. In this thesis, after briefly reviewing
the effect of constant background magnetic field on the propagator considered by Ritus method, we explicitly determine the kinetic terms in terms of Ritus eigenfunctions. Finally, we numerically calculate these terms at finite temperature and chemical potential according to the imaginary time method
the effect of constant background magnetic field on the propagator considered by Ritus method, we explicitly determine the kinetic terms in terms of Ritus eigenfunctions. Finally, we numerically calculate these terms at finite temperature and chemical potential according to the imaginary time method
Shear Viscosities of a Hot Fermi Gas in the Presence of a Strong Magnetic Field
, M.Sc. Thesis Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
Relativistic hydrodynamics and kinetic theory are often used to analyze the experimental data from heavy ion collisions. One of the most important observations is the anisotropy in the number density of the detected particles after the collision in the longitudinal and perpendicular directions with respect to the reaction plane. On the other hand, very strong magnetic fields are created during the early stages of non-central heavy ion collisions. The presence of constant background magnetic fields, aligned in the perpendicular direction to the reaction plane, can be one of reasons for the aforementioned anisotropy in the number density of detected particles. In this thesis, we study the...
On the Effects of Background Electromagnetic elds and Chiral Chemical Potential on the Phase Diagram of Quantum Chromodynamics
, M.Sc. Thesis Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
In particle physics, spontaneous chiral symmetry breaking generates new phases of quark matter, and leads to significant changes od quark masses. The Nambu-Jona–Lasinio (NJL) model is a useful fermionic model which describes the spontaneous chiral symmetry breaking through the creation of a condensate. This model can be for instance used to determine various phases of Quantum Chromodynamics (QCD) in finite electromagnetic fields. This work consists of several parts. First, we describe the spontaneous chiral symmetry breaking in detail. Second, we extract the NJL model from the Lagrangian density of QCD. Third, we derive a covariant form of the partition function of a fermionic system....
Evolution of Electromagnetic Fields in a Plasma of Quarks and Gluons
, Ph.D. Dissertation Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
In heavy ion collisions, extremely large electromagnetic fields are produced by fast-moving charged nucleons. They are sufficiently large to affect the low energy QCD processes and thus produce observable effects, whose occurrence is, however, directly related to the lifetime of these fields. In the present dissertation, the evolution of electromagnetic fields is studied in a plasma of quarks and gluons, by analytically solving the equations of relativistic magnetohydrodynamics (RMHD). The onideal Bjorken RMHD is solved by introducing the method of nonconserved charges. Assuming an electromagnetic force-free condition, the electric and magnetic fields are found to be either parallel or...
Dilepton Production and Synchrotron Radiation in a Magnetized Quark-Qluon Plasma
, M.Sc. Thesis Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
Relativistic collisions of heavy ions lead to the formation of a new phase of matter called Quark-Gluon Plasma (QGP). In addition, strong magnetic fields generates in these collisions that its direction is perpendicular to the collision axis. This strong magnetic field affects the dynamics of particles in the QGP, and causes the appearance of the Landau levels in the particle’s energy spectrum. In this master thesis, we investigate the impact of the magnetic field on dilepton production and synchrotron radiation. We calculate the scattering probability of quark and anti-quark annihilation and dilepton creation by taking all Landau Levels into account. Then, by assuming that the magnetic...
Color Super Counductivity at Finite Temperature, Chemical Potential and in the Presence of Strong Magnetic Fields
, Ph.D. Dissertation Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
In the present thesis, the effect of external magnetic fields on two-flavor Color Superconductive (2SC) phase, as one of the phases in the QCD phase diagram, is studied. To do this, an effective two-flavor Nambu-Jona Lasinio Lagrangian is used, which consists of two mass gaps, s = ?¯qq and ? = ? . The nonzero values of chiral and color mass these gaps induce spontaneous chiral and color symmetry breaking, and consequently two different phases. There is also a third phase, the normal phase, where s = ? = 0. We calculate the transition curves and the critical points in terms of three intensive quantities, the temperature, the chemical potential and the external magnetic field. We study, in...
Magnetic Susceptibility of Qark Matter in the Presence of a Non-Homogeneous Magnetic Field at Finite Temperature and Chemical Potential
, M.Sc. Thesis Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
After the review of formation of Landau levels (LL) in non-relativistic quantum mechanics, we have obtained LL in a certain gauge A_μ=(0,-B_0/2 y,B_0/2 x) at 2+1 &3+1 dimension. then give a summary of Quantum Field Theory at non-zero temperature . obtaining LL and two-point Green function in non-uniform magnetic field which determined with A_μ=(0,0,√qB ξe^(-(t+x) ),0).Next we calculate magnetic susceptibility of in such a field with finite chemical potential and temperature. Finally we compare the obtained results with uniform magnetic field one
On the Effects of Finite Temperature and Background Magnetic Fields on the Observables of Heavy Ion Collisions
, Ph.D. Dissertation Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
The main focus of this dissertation is to investigate the effects of the created background magnetic field on some of the observables that are relevant in heavy ions experiments. Based on the phase diagram of Quantum Chromodynamics, it is expected that in extreme conditions such as high temperature or in dense medium, a new phase of matter arises, which is known as Quark-Gluon Plasma (QGP). Due to the vital role of collective behaviors, this phase behaves similar to a perfect fluid rather than a gas. In addition, the colliding nucleons have potential of creating very strong magnetic fields because of their electric charges and relativistic speeds. Therefore the investigation of the effects...
On the Effect of Ring Diagrams on QCD Phase Transition
, M.Sc. Thesis Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
In this thesis NJL and quark-meson models, as effective models for quantum chro-modynamics in low energies, are studied mainly. After reviewing models and phe-nomena related to the strong interaction in zero and non-zero temperature, firstly the critical coupling of NJL model for non-zero temperature and chemical potential is calculated. Then, the contribution of ring diagrams in the effective potential of quark-meson model is presented. Finaly, the effect of ring diagrams of quark-meson model on chiral phase transition is investigated. For NJL model, it is shown that the chemical potential lowers the critical coupling for chiral phase transition. Also for quark-meson model, it is shown that...
QED Ring Diagrams in Background Magnetic Field at Finite Temperature
, M.Sc. Thesis Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
Using the general structure of the vacuum polarization tensor П_μν (k_0→0,k) in the infrared (IR) limit, k_0→0 , the ring contribution to the QED effective potential at finite temperature and the nonzero magnetic field is determined beyond the static limit, (k_0→0,k→0). The resulting ring potential is then studied in weak and strong magnetic field limits. In the weak magnetic field limit and at high temperature the improved ring potential consists of a term proportional to T^4 α^(5/2), in addition to the expected term T^4 α^(3/2) arising from the static limit. In the limit of the strong magnetic field, where QED dynamics is dominated by the lowest Landau level, the ring potential includes a...
Dirac Fermions in a Chiral Environment under Rigid Rotation
, M.Sc. Thesis Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
In this study, the effect of rigid rotation on the dynamical and thermodynamic properties of Dirac fermions in a chiral environment is investigated. Using the framework of quantum field theory, the Dirac equation is solved in the presence of rigid rotation, and the corresponding propagator is derived using the Fock-Schwinger method. The results demonstrate that the angular velocity Ω acts as an effective chemical potential and plays a significant role in the dynamical behavior of fermions. Using the fermion propagator arising in the first part of this work, the chiral current phenomena, including the Chiral Vortical and the Chiral Vortical Separation Effect is also examined in the presence...
Mass-Radius Relation for a Rotating and Magnetized Neutron Star Using the Nambu-Jona-Lasinio Model
, M.Sc. Thesis Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
One of the most essential concepts for describing neutron stars is investigating their radial mass distribution or mass-radius relation. The aim of this thesis is to evaluate radial mass distribution of neutron stars in the presence of magnetic fields. To achieve this objective we use the Tolman- Oppenheimer-Volkoff equation of hydrostatic equilibrium for non-rotating cases and the Hartle- Thorne equations for rotating cases. olving these equations depends on determination of equation of state of neutron star in the presence of magnetic fields. For determining the corresponding equation of state, one can use QCD-like non-perturbative models, in particular Nambu-Jona- Lasinio (NJL) model. In...
, M.Sc. Thesis Sharif University of Technology ; Sadooghi, Neda (Supervisor)
Abstract
Worldline formalism provides an effective and intuitive method in order to obtain the full prop- agator of a system with definite degrees of freedom and the one-loop effective action of such a system interacting with a background field. The covariance of relations and results facilitates the generalization to more complex geometries and symmetries. Feynman for the first time arrived at a relation for the relativistic orbit of a quantum particle in vacuum. In the same year, Schwinger employed a differential method to address the problem of vacuum polarization. The purpose of the current research is to review both of these methods in their search for a polarized vacuum, Lorentzian and gauge...
Surfactant effects on the particle size, zeta potential, and stability of starch nanoparticles and their use in a pH-responsive manner
, Article Cellulose ; Volume 24, Issue 10 , 2017 , Pages 4217-4234 ; 09690239 (ISSN) ; Kashanian, S ; Hemati Azandaryani, A ; Omidfar, K ; Bazyar, E ; Sharif University of Technology
2017
Abstract
Storage conditions seem to be important in the long-term stability of nanoparticles (NPs). This work studies the effects of surfactants and storage container on particle size distribution and zeta potential during long-term storage of acid hydrolyzed potato starch NPs. The NPs were prepared from potato starch using acid hydrolysis and high-intensity ultrasonication. During the ultrasonic treatment, the surfactants were added dropwise to the solutions to reduce the size and stabilize the formed NPs. Particle size distribution, zeta potential, and FE-SEM were used to characterize the ensuing NPs. Additionally, a 5-month stability study was performed to evaluate the maintenance of potato starch...