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A novel vehicle tracking method with occlusion handling using longest common substring of chain-codes
, Article 2009 14th International CSI Computer Conference, CSICC 2009, Tehran, 20 October 2009 through 21 October 2009 ; 2009 , Pages 176-181 ; 9781424442621 (ISBN) ; Kasaei, S ; Sharif University of Technology
2009
Abstract
Vehicle tracking is an essential requirement of any vision based Intelligent Transportation System for extracting different traffic parameters, efficiently. Handling inter-object occlusion is the most challenging part of tracking as a process of finding and following interested objects in a sequence of video frames. In this paper we present a system, based on code-book background model for motion segmentation and Kalman filter for tracking with a new approach for occlusion. This approach separates occluded vehicles based on longest common substring of chain codes. We use this tracking system to estimate some traffic parameters. Experimental results show the efficiency of the method. ©2009...
Moving vehicle tracking using disjoint-view multicameras
, Article Iranian Journal of Electrical and Electronic Engineering ; Volume 7, Issue 3 , Volume 7, Issue 3 , 2011 , Pages 168-178 ; 17352827 (ISSN) ; Kasaei, S ; Sharif University of Technology
2011
Abstract
Multicamera vehicle tracking is a necessary part of any video-based intelligent transportation system for extracting different traffic parameters; such as link travel times and origin/destination counts. In many applications, it is needed to locate traffic cameras disjoint from each other to cover a wide area. This paper presents a method for tracking moving vehicles in such camera networks. The proposed method introduces a new method for handling inter-object occlusions; as the most challenging part of the single camera tracking phase. This approach is based on coding the silhouette of moving objects before and after occlusion and separating occluded vehicles by computing the longest common...
Moving Vehicle Tracking Using Multiple Uncalibrated Non-overlapped Cameras
, M.Sc. Thesis Sharif University of Technology ; Kasaei, Shohreh (Supervisor)
Abstract
Multi-camera vehicle tracking is a necessary part of any video-based intelligent transportation systems (ITS) for extracting different traffic parameters such as link travel times and Origin/Destination (O/D) counts efficiently. In many applications it is needed to place traffic cameras disjoint from each other to cover wide areas. In this work we present a system for tracking vehicles in such network of cameras. The proposed system includes new ideas for handling inter-object occlusion as the most challenging part of single camera tracking phase. This approach is based on coding silhouette of moving objects before and after occlusion and separating occluded vehicles by finding longest...
Empirical correlation for performance evaluation of electric/corona wind on natural convection
, Article Journal of Electrostatics ; Vol. 72, issue. 1 , February , 2014 , pp. 82-90 ; ISSN: 03043886 ; Shabahang-Nia, E ; Merdasi, A ; Sharif University of Technology
2014
Abstract
The effect of the corona wind on the natural convection at a rectangular channel was investigated experimentally. The results indicate that the natural convection in the absence of electric/corona wind at obtuse angles outperforms than acute angles and keeps improving by increasing the angle. However, the efficiency of the electric/corona wind at acute angles is higher than obtuse angles. Generally, in the presence of electric/corona wind, heat transfer coefficient was increased. The effect of the electric/corona wind was decreased by raising heat flux. This mainly stems from the fact that the temperature gradient raises the thermal boundary layer and reduces the secondary flow power....
Human serum protein adsorption onto synthesis nano-hydroxyapatite
, Article Protein Journal ; Volume 31, Issue 2 , February , 2012 , Pages 150-157 ; 15723887 (ISSN) ; Massah Bidgoli, M ; Behrashi, M ; Mohsen Nia, A ; Sharif University of Technology
2012
Abstract
Adsorption of human serum proteins (Albumin and total protein) onto high purity synthesis nano-hydroxyapatite (HA), Ca 10(PO 4) 6(OH) 2, has been studied in a wide temperature range by UV-visible spectrophotometer. Adsorption isotherm is basically important to describe how solutes interact with adsorbent, andiscriticalinoptimizing the use of adsorbent. Inthe present study, the experimental results werefitted tothe Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (DR) models to obtain the characteristic parameters of each model and square of the correlation coefficients (R 2). According to the results, the DR isotherm model had the best agreement with the experimental data. The effect of...
A heterogeneous diffusive logistic model of a single species population dynamics with predation and harvesting terms
, Article Nonlinear Analysis, Theory, Methods and Applications ; Volume 156 , 2017 , Pages 1-16 ; 0362546X (ISSN) ; Torabi Tehrani, H ; Sharif University of Technology
2017
Abstract
We study existence and multiplicity of positive solutions of a heterogeneous diffusive logistic equation with predation and harvesting terms, −Δu=au−b(x)u2−c, where a,c,m and d are positive constants, Ω a bounded smooth domain in RN, and b(x) is a nonnegative function on Ω¯, with Ω0 a region such that Ω¯0⊂Ω and Ω¯0={x∈Ω:b(x)=0}. Under the strong growth rate assumption, that is, when a is greater than the first eigenvalue of −Δ in Ω0 with Dirichlet boundary condition, we show that the equation has at least one positive solution for 0≤d0. In addition, in case c
Diffusive logistic equations with harvesting and heterogeneity under strong growth rate
, Article Advances in Nonlinear Analysis ; Volume 8, Issue 1 , 2019 , Pages 455-467 ; 21919496 (ISSN) ; Torabi Tehrani, H ; Sharif University of Technology
De Gruyter
2019
Abstract
We consider the equation (equation presented) where Ω is a smooth bounded domain in ℝ N , b(x) and h(x) are nonnegative functions, and there exists Ω 0 ⊃ Ω such that {x : b(x) = 0} = Ω0. We investigate the existence of positive solutions of this equation for c large under the strong growth rate assumption a ≥ λ 1 (Ω0), where λ 1 (Ω0) is the first eigenvalue of the δ in Ω0 with Dirichlet boundary condition. We show that if h = 0 in Ω\u03a90, then our equation has a unique positive solution for all c large, provided that a is in a right neighborhood of λ 1 (Ω0). For this purpose, we prove and utilize some new results on the positive solution set of this equation in the weak growth rate case
Ionization dynamics of orbitals and high-harmonic generation of N2 and CO molecules at the various XC potentials by TD-DFT
, Article Computational and Theoretical Chemistry ; Volume 1095 , 2016 , Pages 104-111 ; 2210271X (ISSN) ; Mohsen Nia, M ; Sadighi Bonabi, R ; Irani, E ; Sharif University of Technology
Elsevier
2016
Abstract
High order harmonic generation is investigated for N2 and CO molecules under ten-cycle sin-squared laser pulse at 800 nm wavelength and I = 2 × 1014 W cm−2 intensity. In order to study effects of the asymptotic behavior of the exchange-correlation (XC) potentials, the time-dependent Kohn-Sham equations are numerically solved in the non-linear non-perturbative regime with four different XC potentials. Time-dependent electron localization function is used to get imaging on the temporal dependence of the electron density. Time-profile analysis was also utilized for studying long and short electron trajectories. It is found that the ionization energy values both molecules calculated by using...
The control of electron quantum trajectories on the high-order harmonic generation of CO and N2 molecules in the presence of a low frequency field
, Article Journal of Chemical Physics ; Volume 148, Issue 14 , 2018 ; 00219606 (ISSN) ; Sadighi Bonabi, R ; Mohsen Nia, M ; Irani, E ; Sharif University of Technology
American Institute of Physics Inc
2018
Abstract
In the present work, an efficient method is theoretically investigated for extending high-order harmonics and ultrashort attosecond pulse generation in N2 and CO molecules by using the time-dependent density functional theory approach. Our results show that by utilizing chirped laser field in the presence of a low frequency field, not only is the harmonic cutoff extended remarkably but also the single short quantum trajectory is selected to contribute to the harmonic spectra. When a low frequency field is added to the two-color chirped laser field, the long quantum trajectories are suppressed and only the short quantum trajectories contribute to the higher harmonic emission mechanism. As a...
High-order harmonic generation of CO and N2 molecules under linearly- and bi circularly-polarized laser pulses by TD-DFT
, Article Laser Physics ; Volume 28, Issue 7 , 2018 ; 1054660X (ISSN) ; Sadighi Bonabi, R ; Mohsen Nia, M ; Irani, E ; Sharif University of Technology
Institute of Physics Publishing
2018
Abstract
We present a method for high-order harmonics generation of N2 and CO molecules under two-color circularly polarized counter-rotating laser pulses at frequencies of and 2. Pulse envelope in this investigation is sin-squared and the intensity of each laser beam is with ten-optical cycle (o.c.). We show that an isolated pulse with a pulse duration shorter than 20 attosecond from the superposition of several harmonics can be generated. Both two-color linearly- and bicircularly-polarized laser pulses are considered. Our results have also been compared with the outcomes of the previous theoretical works as well as experiment observations. It is found that for CO molecule, the...
Design of a pseudo stir bar sorptive extraction using graphenized pencil lead as the base of the molecularly imprinted polymer for extraction of nabumetone
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 238 , 2020 ; Dadfarnia, S ; Haji Shabani, A. M ; Kazemi, E ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Molecularly imprinted polymer (MIP) was synthesized through the coprecipitation method on the graphene oxide anchored pencil lead as a substrate for the first time and applied as an efficient sorbent for pseudo stir bar sorptive extraction of nabumetone. The extracted analyte was determined by a novel spectrophotometric method based on the aggregation of silicate sol-gel stabilized silver nanoparticles in the presence of the analyte. The synthesized polymer was characterized using Fourier transform infrared spectroscopy and field emission scanning electron microscopy. Optimization of important parameters affecting the extraction efficiency was done using central composite design whereas the...
Selective fluorometric determination of sulfadiazine based on the growth of silver nanoparticles on graphene quantum dots
, Article Microchimica Acta ; Volume 187, Issue 1 , 2020 ; Haji Shabani, A. M ; Dadfarnia, S ; Kazemi, E ; Sharif University of Technology
Springer
2020
Abstract
A sensitive fluorometric assay is described for the direct determination of the antibiotic sulfadiazine. Silver nanoparticles placed on graphene quantum dots (Ag NP-GQDs) were synthesized by reduction of AgNO3 with sodium borohydride in the presence of GQDs. The growth of Ag NPs on the surface of the GQDs causes quenching of the blue fluorescence of the GQDs with an emission maximum at 470 nm by surface-enhanced energy transfer. If sulfadiazine is added, it interacts with Ag NPs and fluorescence is restored. Under optimal conditions, the fluorescence increases linearly in the sulfadiazine concentration range of 0.04–22.0 μM. The detection limit is 10 nM with relative standard deviations of...
Diffusive Holling type-II predator-prey system with harvesting of prey
, Article Journal of Mathematical Analysis and Applications ; Vol. 410, issue. 1 , 2014 , pp. 469-482 ; ISSN: 0022247X ; Sharif University of Technology
2014
Abstract
We study diffusive heterogeneous predator-prey system with Holling type-II functional response in the presence of harvesting in prey equation i.e.{-δu=λu-a(x)u2-buv1+mu-ch(x)in Ω,-δv=μv-v2+duv1+muin Ω,∂νu=∂νv=0on ∂Ω, where Ω is a smooth bounded region in RN and a(x) is a nonnegative continuous function on Ω, with Ω0 a region such that Ω⊂Ω and a(x)>0 on Ω\u03a90. We show that in the case of weak prey growth rate, i.e. λ less than the first eigenvalue of -δ in Ω0, the system has a positive solution for the values of μ in a bounded interval and c>0 sufficiently small. We also investigate the multiplicity of positive solutions in this case. When the prey growth rate is strong, we will show that...
Performance analysis and multi-objective optimization of an organic Rankine cycle with binary zeotropic working fluid employing modified artificial bee colony algorithm
, Article Journal of Thermal Analysis and Calorimetry ; 2018 ; 13886150 (ISSN) ; Maghsoudi, P ; Shabani, B ; Gorgani, H. H ; Shabani, N ; Sharif University of Technology
Springer Netherlands
2018
Abstract
From a thermal point of view, zeotropic mixtures are likely to be more efficient than azeotropic fluids in low-temperature power cycles for reduction in exergy destruction occurring during heat absorption/rejection processes due to their suitable boiling characteristics. In this study, comprehensive energetic and exergetic analyses are mathematically performed for an organic Rankine cycle (ORC) system employing a potential binary zeotropic working fluid, namely R717/water. For this purpose, initially mass, energy, and exergy balance equations are derived. With regard to the similarity in molar mass of R717 (17.03 g mol−1) and water (18.01 g mol−1), there is no need to alter the size of the...
Performance analysis and multi-objective optimization of an organic Rankine cycle with binary zeotropic working fluid employing modified artificial bee colony algorithm
, Article Journal of Thermal Analysis and Calorimetry ; Volume 136, Issue 4 , 2019 , Pages 1645-1665 ; 13886150 (ISSN) ; Maghsoudi, P ; Shabani, B ; Gorgani, H. H ; Shabani, N ; Sharif University of Technology
Springer Netherlands
2019
Abstract
From a thermal point of view, zeotropic mixtures are likely to be more efficient than azeotropic fluids in low-temperature power cycles for reduction in exergy destruction occurring during heat absorption/rejection processes due to their suitable boiling characteristics. In this study, comprehensive energetic and exergetic analyses are mathematically performed for an organic Rankine cycle (ORC) system employing a potential binary zeotropic working fluid, namely R717/water. For this purpose, initially mass, energy, and exergy balance equations are derived. With regard to the similarity in molar mass of R717 (17.03 g mol −1 ) and water (18.01 g mol −1 ), there is no need to alter the size of...
Optimal synthesis of planar and spatial mechanism for path generation using regression deviation
, Article Scientia Iranica ; Volume 12, Issue 2 , 2005 , Pages 190-198 ; 10263098 (ISSN) ; Tavakoli Nia, H ; Sharif University of Technology
Sharif University of Technology
2005
Abstract
This method introduces the structural error of regression deviation, which is an effective method for the path generation of a vast type of planar and spatial mechanism. The proposed method avoids point-by-point comparison and requirement of timing and reflects the difference between the two curves very effectively in the objective function. By decreasing the number of the design variables, this method would help considerably in decreasing CPU time. The objective function that is based on regression error would converge to a global minimum by a genetic algorithm. At the end, the effectiveness of the method is shown by two numerical examples. © Sharif University of Technology
Attitude Control of Flexible Satellite using CMG in Slew Maneuver Considering Bending and Torsion Deflections
, M.Sc. Thesis Sharif University of Technology ; Asadian, Nima (Supervisor)
Abstract
In this thesis the attitude dynamics, simulation and control of a flexible satellite with CMG (Control Moment Gyro) actuator in three-dimensional slew and rest-to-rest maneuvers have been studied. The flexible satellite is modeled as a rigid hub and two flexible appendages. The bending and torsion of the flexible panels have been considered. The equations of motion have been derived using the Lagrange method and assumed-modes approach is utilized for converting the partial differential equations of structural dynamics into an ordinary differential equation set. The MATLAB and SIMULINK software has been used for simulation and validation of the equations of motion. The simulation and control...
Modeling of Ground-Level Ozone Concentrations in Tehran using CMAQ Model
, M.Sc. Thesis Sharif University of Technology ; Arhami, Mohammad (Supervisor)
Abstract
Every year, air pollution is causing immense harm to humans and the environment. To cause Air pollution, several factors are involved. Among these are the sources of emissions such as factories, power plants and Cars, meteorological factors such as temperature and wind speed and geographical conditions such as altitude, postal and looming around the area, land slope and soil type region. The aim of this study is to identify factors that affect the ozone concentration in Tehran, which could help identifying other secondary pollutants. For this purpose, a combination tailored to the geography of Tehran using CMAQ-WRF-SMOKE-made programs. This model includes four intervals each of which lasting...
Design and Control of a Robotic Arm and Hand with Simulation on Performance
, M.Sc. Thesis Sharif University of Technology ; Zohour, Hassan (Supervisor)
Abstract
The set of human arm, forearm, and wrist has the ability of performing very miscellaneous movements which has led to human inspiration for designing sorts of robots for various tasks. The aim of the present study is the design and simulation of a robot, similar to the human hand and arm. In the beginning, a shape-adaptive 2 DOF under-actuated mechanism which is actuated by one motor, is selected as the second and third phalanges of the human finger. Also the first phalanx of the finger moves independently by another motor. By adding a ratchet to the second joint of the finger, with the help of only two actuators, the feasibility of exerting isotropic force to the object in three phalanges...
Theoretical Assessment of the Corrosion Inhibitory Effect of Some Derivatized Benzaldehyde Based Schiff Bases
, M.Sc. Thesis Sharif University of Technology ; Gobal, Freydoon (Supervisor)
Abstract
Schiff bases are used as prevalent ligands in coordination chemistry and are prepared easily. Their application as mild inhibitory agents for prevention of various steel’s corrosion in acidic solution has been proved. When their structure is altered, multi-purpose application for them is found. This property has led to a motive for research and study. In this study, electronic properties of a group of Schiff bases are investigated. The goal of this study is using quantum mechanics (QM) as a tool for specifying electronic properties of some of these bases. With respect to QM calculation which is done by density functional theory (DFT), their properties as inhibitory agents are studied. First,...