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jamali-gandomani--hossein
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Photocatalytic Conversion of CO2 under Visible Light Irradiation
, M.Sc. Thesis Sharif University of Technology ; Khorasheh, Farhad (Supervisor) ; Hamzehlouyan,Tayebeh (Supervisor) ; Larimi, Afsanehsadat (Supervisor)
Abstract
The photoreduction of CO2 to produce renewable solar fuel known as artificial photosynthesis attracted a lot of attention during the last two decades due to the global warming issue caused through increasing CO2 and shortage of fossil fuels resources. In this study, in order to enhance photocatalytic process of CO2 under visible light, TiO2-graphene and TiO2-copper nanocomposite utilized. A series of Cu/TiO2 photocatalysts were prepared with various Cu (2, 5 and 8 wt%) and a series of G/TiO2 photocatalysts with different graphene (G) content (5, 20 and 40 wt.%) were prepared and tested for the reduction of CO2. XRD, BET, DRS and TEM analyses employed to characterize the catalyst while the...
Spontaneous Order of Market and Institutional Challengaes
, M.Sc. Thesis Sharif University of Technology ; Mirjalili, Hossein (Supervisor)
Abstract
Hayek is one of the most impressive figures of Austrian School of Economics established by Carl Menger. The Thinkers of this school of thought believed that governments should not intervene in the market process. They argued that such interventions would spoil the market performance in resource allocation. Hayek believes that the order which emerges from the market is a spontaneous one; it means no one has designed it, but it has evolutionarily evolved by distinctive agents' actions who had no plan to make it. Hayek's arguments for spontaneous order are based on some epistemological presuppositions such as: "methodological individualism", "methodological subjectivism", "tacit knowledge" and...
Vibration and Buckling Analysis of Multi-walled Carbon Nanocone by Molecular Mechanics Approach and Stability Analysis of Carbon Nanocone Conveying Fluid
, M.Sc. Thesis Sharif University of Technology ; Haddadpour, Hassan (Supervisor)
Abstract
In this thesis, vibration analysis of multi-walled carbon nanoconesstudied by molecular mechanics approach. In this simulation, atoms of carbon and bondings of them modeled by concentrated mass and structural elements, respectively and then mode shapes and natural frequencies of these structures calculated and effects of height, apex angle, boundary conditions and number of layers on natural frequencies of carbon nanocones studied. Also, critical buckling load of multi-walled carbon nanocones due to axial and in-plane loads obtained and effects of height, apex angle and number of layers on critical buckling loads of carbon nanocones studied. These results validated by molecular dynamics and...
Improving Robustness of Deep Neural Networks Against Query-based Adversarial Attacks
, M.Sc. Thesis Sharif University of Technology ; Jalili, Rasool (Supervisor)
Abstract
In recent years, deep neural networks have been widely used in various applications such as image classification and malware detection. However, these networks are vulnerable to a type of attack called adversarial attacks, where, the attacker tries to cause the target model to misclassify the input image by adding a small amount of perturbation to the input image in a way that is often undetectable to humans. A special type of such attacks that can be applied in real-world conditions can be used without knowledge of the architecture and parameters of the model and only by sending a query and receiving the probability vector or the correct label, which are called black box attacks. such...
Numerical Analysis of Channel Flow over an Elastic Bump, Using Lattice Boltzmann Method- A Biological Application
, M.Sc. Thesis Sharif University of Technology ; Taeibi Rahni, Mohammad (Supervisor)
Abstract
In recent years, lattice Boltzmann method (LBM) has been developed to be used as an alternative and promising computational technique to simulate various flows. It originates from classical statistical physics. The ability to simply solve complex flows, simulating of multiphase and multi-component without need to follow the boundaries of different phases, and the inherent ability of parallel processing are notable features of this approach. On the other hand, finite element method (FEM) is widely used in many practical engineering fields, especially in solid mechanics. In this study, in addition to simulating flow over a rigid body, flow over an elastic body is also simulated with a...
A proposed mechanism for mind-brain interaction using extended Bohmian quantum mechanics in Avicenna's monotheistic perspective
, Article Heliyon ; Volume 5, Issue 7 , July , 2019 ; 24058440(ISSN) ; Golshani, M ; Jamali, Y ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In quantum approaches to consciousness, the authors try to propose a model and mechanism for the mind-brain interaction using modern physics and some quantum concepts which do not exist in the classical physics. The independent effect of mind on the brain has been one of the challenging issues in the history of science and philosophy. In some recent mind-brain interaction models, the direct influence of mind on matter is either not accepted (as in Stapp's model) or not clear, and there have not been any clear mechanism for it (as in Penrose-Hameroff's model or in Eccles's model). In this manuscript we propose a model and mechanism for mind's effect on the matter using an extended Bohmian...
A proposed mechanism for mind-brain interaction using extended Bohmian quantum mechanics in Avicenna's monotheistic perspective
, Article Heliyon ; Volume 5, Issue 7 , 2019 ; 24058440 (ISSN) ; Golshani, M ; Jamali, Y ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In quantum approaches to consciousness, the authors try to propose a model and mechanism for the mind-brain interaction using modern physics and some quantum concepts which do not exist in the classical physics. The independent effect of mind on the brain has been one of the challenging issues in the history of science and philosophy. In some recent mind-brain interaction models, the direct influence of mind on matter is either not accepted (as in Stapp's model) or not clear, and there have not been any clear mechanism for it (as in Penrose-Hameroff's model or in Eccles's model). In this manuscript we propose a model and mechanism for mind's effect on the matter using an extended Bohmian...
Dynamic stability analysis of single walled carbon nanocone conveying fluid
, Article Computational Materials Science ; Volume 113 , 2016 , Pages 123-132 ; 09270256 (ISSN) ; Noorian, M. A ; Haddadpour, H ; Fotouhi, M. M ; Sharif University of Technology
Elsevier
2016
Abstract
This report aims the study of dynamic stability of single walled carbon nanocone for some axial length conditions and declination angles of 60°, 120°and 240°. For dynamic stability analysis of Single Walled Carbon Nanocone (SWCNC), the mode shapes and frequencies of the carbon nanocone are extracted using the molecular mechanics approach. The mechanical properties of SWCNC were obtained by the Molecular Mechanics (MM) method. The obtained parameters are used for extraction of the conical shell virtual model of nanocone with the same dimensions. The equations of coupled fluid-structural dynamics of SWCNC are derived using the modal expansion for the structural displacements of the conical...
Non-hydrostatic layered flows over a sill
, Article Fluid Dynamics Research ; Volume 45, Issue 2 , February , 2013 ; 01695983 (ISSN) ; Sharif University of Technology
2013
Abstract
This work takes a new approach to solving non-hydrostatic equations of layered flows over bottom topography. A perturbation technique is used to find explicit expressions for a flow for different regimes of single- and two-layer flows over a sill. Excellent agreement with previous solutions and experimental data is obtained, and more details of the non-hydrostatic flow over a sill are revealed. The proposed method is simple and compact and removes the need for complex numerical techniques to solve the non-hydrostatic equations. It is shown that in the approach-controlled regime of two-layer flow over a sill, the flow upstream and farther downstream the sill crest can be described by the...
BEM modeling of surface water wave motion with laminar boundary layers
, Article Engineering Analysis with Boundary Elements ; Volume 30, Issue 1 , 2006 , Pages 14-21 ; 09557997 (ISSN) ; Sharif University of Technology
2006
Abstract
This study is concerned with numerical modeling of viscous surface wave motion using boundary element method (BEM). The equations of motion for thin boundary layers at the solid surfaces are coupled with the potential flow in the bulk of the fluid, and a mixed BEM-finite difference technique is used to obtain the viscosity-related quantities such as wave damping rate, shear stress, and velocity distribution inside the boundary layer. The technique is presented for standing surface wave motion. An excellent agreement is obtained between the numerical predictions and the previous results. The extension to other free surface problems is straightforward. © 2005 Elsevier Ltd. All rights reserved
A coupled boundary element-finite difference model of surface wave motion over a wall turbulent flow
, Article International Journal for Numerical Methods in Fluids ; Volume 51, Issue 4 , 2006 , Pages 371-383 ; 02712091 (ISSN) ; Sharif University of Technology
2006
Abstract
An effective numerical technique is presented to model turbulent motion of a standing surface wave in a tank. The equations of motion for turbulent boundary layers at the solid surfaces are coupled with the potential flow in the bulk of the fluid, and a mixed BEM-finite difference technique is used to model the wave motion and the corresponding boundary layer flow. A mixing-length theory is used for turbulence modelling. The model results are in good agreement with previous physical and numerical experiments. Although the technique is presented for a standing surface wave, it can be easily applied to other free surface problems. Copyright © 2005 John Wiley & Sons, Ltd
Topographic effects on establishment of selective withdrawal
, Article Physics of Fluids ; Volume 15, Issue 12 , 2003 , Pages 3665-3670 ; 10706631 (ISSN) ; Sharif University of Technology
American Institute of Physics Inc
2003
Abstract
This study is concerned with evolution of selective withdrawal of a linearly stratified fluid through a line sink at the base of a reservoir with bottom topography in the form of a sill of small height. The problem is investigated theoretically in the linear, inviscid limit using a perturbation technique. The induced flow due to motion of the first few shear waves is studied. It is shown that the effect of a sill on the flow field is confined mostly to the withdrawal layer in the vicinity of the sill. Equations are proposed for the steady withdrawal layer thickness and the critical Froude number in the presence of a sill. © 2003 American Institute of Physics
Numerical modeling of surface wave motion with a bottom turbulent boundary layer
, Article 24th International Conference on Offshore Mechanics and Arctic Engineering, 2005, Halkidiki, 12 June 2005 through 17 June 2005 ; Volume 3 , 2005 , Pages 923-926 ; Sharif University of Technology
2005
Abstract
An effective numerical technique is presented to model turbulent motion of a standing surface wave in a tank. The equations of motion for turbulent boundary layers at the solid surfaces are coupled with the potential flow in the bulk of the fluid, and a mixed BEM-finite difference technique is used to obtain the wave and boundary layer characteristics such as bed shear stress. A mixing-length theory is used for turbulence modeling. Although the technique is presented for a standing surface wave, it can be easily applied to other free surface problems. Copyright © 2005 by ASME
BEM modeling of viscous motion of surface water waves
, Article 23rd International Conference on Offshore Mechanics and Arctic Engineering, Vancouver, BC, 20 June 2004 through 25 June 2004 ; Volume 3 , 2004 , Pages 557-561 ; Sharif University of Technology
2004
Abstract
This study is concerned with numerical modeling of viscous surface wave motion using boundary element method (BEM). The equations of motion for thin boundary layers at the solid surfaces are coupled with the potential flow in the bulk of the fluid, and a mixed BEM-finite difference technique is used to obtain the surface wave motion characteristics including the decay rate. The technique is presented for a standing surface wave motion. The extension to other free surface problems is discussed
Effects of a sill on selective withdrawal through a point sink in a linearly stratified fluid
, Article Advances in Water Resources ; Volume 33, Issue 12 , 2010 , Pages 1517-1523 ; 03091708 (ISSN) ; Haddadzadegan, H ; Sharif University of Technology
2010
Abstract
Reservoir topography has significant effects on mechanism of selective withdrawal. We study selective withdrawal of a linearly stratified fluid through a point sink in a long rectangular reservoir with a sill at the bed experimentally and analytically. Experiments were conducted for various flow rates and sill heights to evaluate their effects on withdrawal layer in the inertial-buoyancy regime. Transition to the steady state is discussed in terms of dynamics of shear waves over the sill. The results show that in presence of a sill the withdrawal layer is thicker and higher in elevation. For flows controlled at the sill crest, the withdrawal layer thickness in the point-sink flow is almost...
Numerical simulation of base-isolated systems sliding on concave surfaces
, Article Asian Journal of Civil Engineering ; Volume 11, Issue 1 , 2010 , Pages 123-133 ; 15630854 (ISSN) ; Jamali, S ; Sharif University of Technology
2010
Abstract
Base isolation is an acknowledged means to reduce the transmission of earthquake accelerations from the ground into the structure. Of particular interest here are systems where the bearing slides on a concave surface which produces a self-centering force restoring the building to its original position. While the idea behind the technology is straightforward, the numerical simulation of the structural response is difficult, since the contact between the bearing and the sliding surface changes continually between sticking and sliding in a nonlinear process. The research presented here aims at developing a computational model for base-isolated building which would allow the engineer to simulate...
Quantitative evaluation of parameters affecting the accuracy of Microsoft Kinect in GAIT analysis
, Article 2016 23rd Iranian Conference on Biomedical Engineering and 2016 1st International Iranian Conference on Biomedical Engineering, ICBME 2016, 23 November 2016 through 25 November 2016 ; 2017 , Pages 306-311 ; 9781509034529 (ISBN) ; Behzadipour, S ; Sharif University of Technology
2017
Abstract
To date various commercial systems have been used in the GAIT analysis. These systems have some difficulties for clinical use, such as interfering with normal movement and high prices. The possibility of utilization of Kinect as a sensor for GAIT analysis has been studied in this research. The accuracy of Kinect in calculation of GAIT parameters such as lower limb joint angles, stride time, and stride length were computed during normal walking. The effects of the sensor's position and direction relative to the walkway were also investigated. The Kinect sensor was installed at different positions toward the motion path. In each position the data was recorded by both Kinect and a commercial...
Experimental study of lateral dispersion in flexible aquatic canopy with emergent blade-like stems
, Article Physics of Fluids ; Volume 32, Issue 6 , 25 June , 2020 ; Sehat, H ; Sharif University of Technology
American Institute of Physics Inc
2020
Abstract
This paper quantitatively investigates the role of flexibility of blade-like stems and, in particular, the occurrence of stem resonance on lateral dispersion in emergent aquatic canopies. Two sets of experiments are presented: single-stem and canopy tests. In the first set, the flow around single blade-like flexible model stems and the proximity to a resonant state are studied. Wake areas behind four model stems with distinct flexibilities are measured by particle image velocimetry for stem Reynolds numbers between 350 and 850. A single flexible emergent stem bends and oscillates in in-line and cross-flow directions due to periodic forcing associated with the vortex shedding. The plant...
Effect of a contraction on selective withdrawal of a linearly stratified fluid from a line sink
, Article Physics of Fluids ; Volume 19, Issue 10 , 2007 ; 10706631 (ISSN) ; Aghsaee, P ; Sharif University of Technology
American Institute of Physics Inc
2007
Abstract
This study is concerned with a theoretical and laboratory investigation of selective withdrawal of a linearly stratified fluid through a line sink at the base of a reservoir with a side contraction. The width-averaged equations of motion are solved numerically. The evolution of selective withdrawal and the flow properties at the steady state are studied. Using the numerical results, an equation is proposed for the withdrawal layer thickness, the critical Froude number, and the density thickness. For comparison, experiments were conducted in a flume and particle image velocimetry technique was used to capture the flow field upstream of a contraction during evolution of selective withdrawal....
Different aspects of social network analysis
, Article 2006 IEEE/WIC/ACM International Conference on Web Intelligence, WI'06, Hong Kong, 18 December 2006 through 22 December 2006 ; 2006 , Pages 66-72 ; 0769527477 (ISBN); 9780769527475 (ISBN) ; Abolhassani, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2006
Abstract
A social network is a set of people (or organizations or other social entities) connected by a set of social relationships, such as friendship, co-working or information exchange. Social network analysis focuses on the analysis of patterns of relationships among people, organizations, states and such social entities. Social network analysis provides both a visual and a mathematical analysis of human relationships. Web can also be considered as a social network. Social networks are formed between Web pages by hyperlinking to other Web pages. In this paper a state of the art survey of the works done on social network analysis ranging from pure mathematical analyses in graphs to analyzing the...