Relay-assisted Multiple-input Multiple-output Underwater Wireless Optical Communication Systems

, M.Sc. Thesis Sharif University of Technology Jamali, Mohammad Vahid (Author) ; Salehi, Javad (Supervisor)

Abstract

Today’s growing interest to the underwater explorations and navigations demands to design appropriate underwater communication methods and systems. However, radio frequencies which are widely being used in free space communications, can’t be a good candidate for underwater wireless communications, due to their sever attenuation in water. On the other hand, underwater acoustic communication has been widely studied and implemented in the past decades, inspired by suitable propagation of acoustic waves through the underwater medium. Nevertheless, acoustic communication systems have limited bandwidth, lower propagation speed and lower security than optical counterparts, which suggests underwater...

Effect of Aquatic Plants on Hydrodynamic and Dispersion in the Wave Motion

, Ph.D. Dissertation Sharif University of Technology Tofighi, Mohammad Ali (Author) ; Jamali, Mirmosadegh (Supervisor)

Abstract

Aquatic plants play an important role in water environment. Increasing drag force, distorting the velocity and turbulence structures and other related parameters, are the results of the presences of plants. These changes affect the dispersion and mass transport in the aquatic areas. This thesis presents laboratory visualizations and measurements of wave motion, and passive solute surface dispersion (longitudinal and lateral) in arrays of cylinders, a model for emergent, rigid aquatic plants. In the range of (where is Keulegan–Carpenter number, is the maximum oscillatory velocity perpendicular to the cylinder axis, is the period of oscillation, and is the diameter of the cylinder), and (where...

Experimental Study of Hydraulic Characteristics of Perforated Pipes in Submerged Area

, M.Sc. Thesis Sharif University of Technology Olyaei, Mohammad Ali (Author) ; Jamali, Mir Mosaddegh (Supervisor)

Abstract

In small settling tanks, the sludges can be removed using perforated pipes. In this method the pipe is placed in the depth of a fluid and the lateral inflow through perforations lead to the outlet. Since there are few researches about hydraulic characteristic of perforated pipes, this research will investigate the hyadraulic characteristic of these pipes experimentally. One of the main objectives of these pipes is to use the entire lenghte of the pipe and also provide the uniform distribution of inflow. In the past studies, it was found out that inflow mostly comes through downstream perforations. The objective of this research is to find the distribution of discharge along the perporated...

Interaction of Surface and Interfacial Waves Over Fluid Mud Bed

, Ph.D. Dissertation Sharif University of Technology Aleebrahim Dehkordi, Mohammad Ali (Author) ; Jamali, Mirmosadegh (Supervisor)

Abstract

Motivated by the role of interfacial instabilities in sediment resuspension, this paper provides quantitative measurements of the long-time behavior of the interfacial waves and the changes in vertical density during motion of a surface wave over a muddy bed. After an initial fluidization process, a 3D quasi-standing interfacial wave was observed at the interface as a result of a resonant wave interaction with the surface wave. In the process, the quasi-standing wave started growing exponentially at a rate of 0.052-0.081 1/s and then reached a maximum amplitude (kexpb=0.77-0.83). The interfacial wave then took a downward trend in the transition stage and approached a steady state...

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) Jamali, M ; 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) Jamali, M ; 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...

Management Treatment of MDF Effluent by Soil Aquifer Treatment (SAT)

, M.Sc. Thesis Sharif University of Technology Aghel Dashghapou, Behnam (Author) ; Oskoee, Mohammad Mahdi (Supervisor) ; Jamali, Sirous (Co-Advisor)

Abstract

This study deals with the treatment of medium density fiberboard (MDF) effluent aiming at the removal of TSS, COD, BOD and Turbidity by means of soil aquifer treatment (SAT). Removal of parameters were evaluated during transport of MDF effluent under unsaturated flow conditions in 1-m soil (sandy-clay soil) depth. The experimental results showed that the new process with SAT to be very effective. The TSS, COD, BOD and turbidity removal average was about 99%, 30%, 89 and 98.5% at the optimum operation condition, respectively. The SAT should be added before the UASB in order to achieve high removal rate of COD and BOD. The UASB (concentration sludge 40000 mg/l) after SAT treatment MDF...

Non-hydrostatic layered flows over a sill

, Article Fluid Dynamics Research ; Volume 45, Issue 2 , February , 2013 ; 01695983 (ISSN) Jamali, M ; 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) Jamali, M ; 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) Jamali, M ; 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) Jamali, M ; 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 Jamali, M ; 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 Jamali, M ; 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

Reaction kinetics investigation of 1-fluoro-2,4-dinitrobenzene with substituted anilines in ethyl acetate–methanol mixtures using linear and nonlinear free energy relationships

, Article Journal of Physical Organic Chemistry ; Volume 24, Issue 11 , November , 2011 , pages 1095–1100 Jamali-Paghaleh, J. (Javad) ; Harifi-Mood, A. R. (Ali Reza) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology

2011

Abstract

Aromatic nucleophilic substitution reaction of 1-fluoro-2,4-dinitrobenzene with para-substituted and meta-substituted anilines was kinetically investigated in the mixtures of ethyl acetate and methanol at room temperature. The correlation of second-order rate coefficients with Hammett's substituent constants yields a fairly linear straight line with negative slope in different mole fractions of ethyl acetate–methanol mixtures. The measured rate coefficients of the reaction demonstrated a dramatic variation in ethyl acetate–methanol mixtures with the increasing mole fraction of ethyl acetate. Linear free energy relationship (LFER) investigations confirm that polarity has a major effect on the...

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) Jamali, M ; 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, N ; 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) Jamali, Z ; 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 Jamali, M ; 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) Jamali, M ; 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) Jamali, M ; 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...