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rezaeian--mahdi
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Thermal-hydraulic Analysis of Dry Storage Cask of the Spent Nuclear Fuel and Construction of a Prototype Experimental Setup for its Simulation
, M.Sc. Thesis Sharif University of Technology ; Outokesh, Mohammad (Supervisor) ; Mousavian, Khalil (Supervisor) ; Rezaeian, Mahdi (Co-Supervisor)
Abstract
Storage of the spent nuclear fuels is one of the topics of interest in recent years and many researches have been conducted in this field in order to design storage casks for spent nuclear fuels. In this study, thermal-hydraulic analysis of a dry storage cask for Bushehr Nuclear Power Plant spent nuclear fuels is carried out. Geometry of the analyzed cask is taken from a Russian transportation cask TK-13. Drawing of the geometry is achieved with SolidWorks and it’s meshing is completed in Gambit. 3 different cases were considered for cask’s geometry and design: cask without spacers inside, cask with spacers inside, and cask with spacers inside and fins on the outside surface of the cask....
An enhancement in the photocatalytic activity of TiO 2 by the use of Pd: The question of layer sequence in the resulting hierarchical structure
, Article Journal of Coatings Technology Research ; Volume 8, Issue 1 , January , 2011 , Pages 75-81 ; 15470091 (ISSN) ; Ghorbani, M ; Mohsenzadeh, M ; Sharif University of Technology
2011
Abstract
TiO 2 and Pd-modified TiO 2 photocatalysts were prepared by sol-gel method. X-ray diffraction (XRD) data showed that the presence of Pd in TiO 2 catalyst decreases the crystalline size of TiO 2 and stabilizes anatase phase. The study of the photocatalytic activity of the films via Linear Sweep Voltametry (LSV) plots and antibacterial test against Escherichia coli ATCC 25922-a gram negative bacterium-showed that Pd increases the photocatalytic activity of the coatings. Besides, the sequence of layer deposition (TiO 2 and Pd-modified TiO 2) influences the photocatalytic properties. In other words, more photocatalytic activity is obtained when Pd-modified layer is deposited first
Optimization of kinematic redundancy and workspace analysis of a dual-arm cam-lock robot
, Article Robotica ; Volume 34, Issue 1 , 2016 , Pages 23-42 ; 02635747 (ISSN) ; Ghaemi Osgouie, K ; Meghdari, A ; Sharif University of Technology
Cambridge University Press
2016
Abstract
In this paper, the problem of obtaining the optimal trajectory of a Dual-Arm Cam-Lock (DACL) robot is addressed. The DACL robot is a reconfigurable manipulator consisting of two cooperative arms, which may act separately. These may also be cam-locked in each other in some links and thus lose some degrees of freedom while gaining higher structural stiffness. This will also decrease their workspace volume. It is aimed to obtain the optimal configuration of the robot and the optimal joint trajectories to minimize the consumed energy for following a specific task space path. The Pontryagin's Minimum Principle is utilized with a shooting method to resolve kinematic redundancy. Numerical examples...
Computer simulation of knee arthrometry to study the effects of partial ACL injury and tibiofemoral contact
, Article 30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS'08, Vancouver, BC, 20 August 2008 through 25 August 2008 ; 2008 , Pages 895-898 ; 9781424418152 (ISBN) ; Farahmand, F ; Rezaeian, T ; Parnianpour, M ; Sharif University of Technology
IEEE Computer Society
2008
Abstract
We simulated the knee arthrometry test to obtain a deeper understanding of the joint's stability behavior and interpret the arthrometric results more effectively. A 2D sagittal plane finite element model of the lower limb in the standard configuration of knee arthrometry was developed using ANSYS APDL. A detailed model of the knee joint was considered including the femoral articulating contour represented by an ellipse, the tibial plateau represented by a circular arc, and four major knee ligaments and their individual bundles represented by linear and nonlinear tensile springs. A deformable layer of articular cartilage was also considered over the tibial plateau to simulate the bones...
Optimization of an Integrated Reservoir-Production System Using Polynomial Chaos Expansion and Sobol Sensitivity Analysis
, Article SPE Reservoir Evaluation and Engineering ; Volume 26, Issue 3 , 2023 , Pages 938-956 ; 10946470 (ISSN) ; Jahanbakhshi, S ; Shaygan, K ; Jamshidi, S ; Sharif University of Technology
Society of Petroleum Engineers (SPE)
2023
Abstract
Integrated reservoir-production modeling is a collaborative multidisciplinary tool that can facilitate optimization of oil and gas production operations during the field development planning stage of exploiting subsurface resources. The critical issue with this technique is the excessive computational burden of the large integrated model with many input variables, which has not been effectively addressed to date. This study aims to reduce the computational costs and runtimes associated with the production integration and optimization process from oil fields. To do so, the reservoir and the surface network models of an Iranian oil field were coupled to create an integrated model for the...
Application of Artificial Intelligence for Screening of Improved Oil Recovery Methods
, M.Sc. Thesis Sharif University of Technology ; Jamshidi, Saeid (Supervisor) ; Jahanbakhshi, Saman (Co-Supervisor)
Abstract
To achieve the highest amount of FOPT during reservoir life and the most net present value, the parameters that are effective in the production of the field are adjusted to be the best performance. In order to achieve these conditions, the reservoir model and the surface will be checked integrated so that the optimal mode of each parameter is determined in interaction with other parameters, so the first integrated model of the reservoir and the surface and then optimizing the target functions of cumulative production and the net present value is performed using the genetic algorithm.Since the number of parameters of reservoir model and surface in the studied field in this study is high,...
Implementation of optical tracker system for marker-based human motion tracking
, Article 15th IASTED International Conference on Applied Simulation and Modelling, Rhodes, 26 June 2006 through 28 June 2006 ; Volume 2006 , 2006 , Pages 252-257 ; 0889865612 (ISBN); 9780889865617 (ISBN) ; Hoviatalab, M ; Rezaeian, T ; Alizadeh, M ; Bostan, M ; Sharif University of Technology
2006
Abstract
In this paper a complete design of a high speed optical human motion tracking system has been described for biomechanical human motion analysis and animation craft applications. The main core of the image processing unit that is implemented by the differential algorithm procedure and some intelligent and conservative procedures that facilitate the search algorithm have also been proposed and implemented for the processing of human motions tracking images. In the next step an optimized modified direct linear transformation (MDLT) method has been used to reconstruct 3D locations of markers as an input data for animation unit. The low computational cost and the high precision in detecting and...
Green synthesis of silica nanoparticles from olive residue and investigation of their anticancer potential
, Article Nanomedicine ; Volume 16, Issue 18 , 2021 , Pages 1581-1593 ; 17435889 (ISSN) ; Afjoul, H ; Shamloo, A ; Maleki, A ; Afjoul, N ; Sharif University of Technology
Future Medicine Ltd
2021
Abstract
Graphical abstract
Novel size-based design of spiral microfluidic devices with elliptic configurations and trapezoidal cross-section for ultra-fast isolation of circulating tumor cells
, Article Talanta ; Volume 254 , 2023 ; 00399140 (ISSN) ; Maleki, S ; Rezaeian, M ; Haki, M ; Shamloo, A ; Sharif University of Technology
Elsevier B.V
2023
Abstract
Investigation and analysis of circulating tumor cells (CTCs) have been valuable resources for detecting and diagnosing cancer in its early stages. Recently, enumeration and separation of CTCs via microfluidic devices have attracted significant attention due to their low cost and easy setup. In this study, novel microfluidic devices based on size-dependent cell-sorting with a trapezoidal cross-section and elliptic spiral configurations were proposed to reach label-free, ultra-fast CTCs enrichment. Firstly, the possibility and quality of separation in the devices were evaluated via a numerical simulation. Subsequently, these devices were fabricated to investigate the effects of the altering...
Experimental and Numerical Study of The Production of Alginate Microgels and Cancer Spheroids by Droplet-Based Microfluidic
, M.Sc. Thesis Sharif University of Technology ; Shamloo, Amir (Supervisor) ; Kazemzadeh Hannani, Siamak (Supervisor)
Abstract
Significant advances in biotechnology have led to the emergence of a cost-effective way with less ethical issues to study disease, organ functions, tumors, and their response to drugs besides studying on animals. Microfluidic devices and organ on a chip (tumor on a chip) were introduced to remove those obstacles. Organ on a chip is a powerful tool for studying different types of tissues and simulating diseases, especially cancers, for biological and medical applications. Organ (tumor) on a chip is considered as a smaller scale of the real organ or tumor and it causes to the real-time study of tissues and their functions more accurately. In this study, to fabricate a droplet-based...
The effect of non-uniform magnetic field on the efficiency of mixing in droplet-based microfluidics: a numerical investigation
, Article Micromachines ; Volume 13, Issue 10 , 2022 ; 2072666X (ISSN) ; Nouri, M ; Hassani Gangaraj, M ; Shamloo, A ; Nasiri, R ; Sharif University of Technology
MDPI
2022
Abstract
Achieving high efficiency and throughput in droplet-based mixing over a small characteristic length, such as microfluidic channels, is one of the crucial parameters in Lab-on-a-Chip (LOC) applications. One solution to achieve efficient mixing is to use active mixers in which an external power source is utilized to mix two fluids. One of these active methods is magnetic micromixers using ferrofluid. In this technique, magnetic nanoparticles are used to make one phase responsive to magnetic force, and then by applying a magnetic field, two fluid phases, one of which is magneto-responsive, will sufficiently mix. In this study, we investigated the effect of the magnetic field’s characteristics...
Design of a marker-based human motion tracking system
, Article Biomedical Signal Processing and Control ; Volume 2, Issue 1 , 2007 , Pages 59-67 ; 17468094 (ISSN) ; Hoviattalab, M ; Rezaeian, T ; Alizadeh, M ; Bostan, M ; Mokhtarzadeh, H ; Sharif University of Technology
2007
Abstract
In this paper a complete design of a high speed optical motion analyzer system has been described. The main core of the image processing unit has been implemented by the differential algorithm procedure. Some intelligent and conservative procedures that facilitate the search algorithm have also been proposed and implemented for the processing of human motions. Moreover, an optimized modified direct linear transformation (MDLT) method has been used to reconstruct 3D markers positions which are used for deriving kinematic characteristics of the motion. Consequently, a set of complete tests using some simple mechanical devices were conducted to verify the system outputs. Considering the system...
Optimization of Kinematic Redundancy and Manipulability Analysis of a Dual-Arm Cam-Lock Robot
, M.Sc. Thesis Sharif University of Technology ; Ghaemi Osguei, Kambiz (Supervisor) ; Meghdari, Ali ($item.subfieldsMap.e)
Abstract
Cooperative systems have been widely studied in literature. The Dual-Arm Cam-Locked (DACL) robot manipulators are reconfigurable arms formed by two parallel cooperative manipulators which operate redundantly but they may lock into each other in specific joints to increase structural stiffness in the cost of losing some degrees of freedom. Obtaining the optimal configuration demands lots of computational time and is not practical in real-time applications. In the present work, considering the kinematics of the manipulator, the optimal control problem of redundancy is formulated in the framework of tasks with the order of priority. The optimal control formulation is derived by using the...
MBBR and MBR Reactor Configuration for Better Performance
, M.Sc. Thesis Sharif University of Technology ; Borgheei, Mahdi (Supervisor)
Abstract
Membrane bioreactors (MBRs) which are commonly understood as the combination of membrane filtration and biological treatment using activated sludge have several advantages, but membrane fouling reduces the membrane efficiency, permeability and lifetime. An alternative is replacing a moving bed biofilm reactor (MBBR) with the activated sludge system which may reduce the effect of membrane fouling. The sludge produced in MBBRs has poor settling characteristics, therefore, their efficiency is limited by the sedimentation tank performance and they require a larger settling surface. The combination of moving bed biofilm reactors and membrane bioreactors can compensate for the drawbacks of both of...
Electromyographic analysis of anterior cruciate deficient knees with and without functional bracing during lunge exercise
, Article Prosthetics and Orthotics International ; Volume 40, Issue 2 , 2016 , Pages 270-276 ; 03093646 (ISSN) ; Farahmand, F ; Rezaeian, T ; Ramsey, D. K ; Mousavi, S. M. E ; Sharif University of Technology
SAGE Publications Inc
2016
Abstract
Background: The use of functional knee braces for returning to sports or during demanding activities following anterior cruciate ligament rupture is common; yet despite being commonly prescribed, its mechanism of action remains unknown. Objectives: To examine the effect of functional knee braces on mean muscle activity when performing lunge exercises. Study design: Pre-/post-test (within-subject research design). Methods: A total of 10 male participants with unilateral isolated anterior cruciate ligament deficiency participated. Electromyographic activities of six muscles around the knee were recorded during lunge exercises, with and without wearing a custom functional knee brace. The lunge...
A multiobjective integrated multiproject scheduling and multiskilled workforce assignment model considering learning effect under uncertainty
, Article Computational Intelligence ; Volume 36, Issue 1 , February , 2020 , Pages 276-296 ; Seyyed Esfahani, M. M ; Mahdavi, I ; Mahdavi Amiri, N ; Rezaeian, J ; Sharif University of Technology
Blackwell Publishing Inc
2020
Abstract
Today, organizations try to decline academically expenses using humans and resources in addition to rising managers and operators' satisfaction. Meantime, a very important step in the process of decision is the assignment of human resources, particularly in connection with research and development (R&D) projects in which the system is highly dependent on the capabilities of human resources. In this study, we tried all the assumptions that come true in the real world, considered a model for applied R&D projects to reduce costs and increase the efficiency of projects. Therefore, an integrated multiproject scheduling and multiskill human resource assignment model under uncertainty has developed...
Forecasting the effects of a Canada-US currency union on output and prices: A counterfactual analysis
, Article Journal of Forecasting ; Volume 32, Issue 7 , 2013 , Pages 639-653 ; 02776693 (ISSN) ; Sharif University of Technology
2013
Abstract
This paper is a counterfactual analysis investigating the consequences of the formation of a currency union for Canada and the USA: whether outputs increase and prices decrease if these countries form a currency union. We use a two-country cointegrated model to conduct the counterfactual analysis, where the conditional forecasts are generated based on the Gaussian assumption. To deal with structural breaks and model uncertainty, conditional forecasts are generated from different models/estimation windows and the model-averaging technique is used to combine the forecasts. We also examine the robustness of our results to parameter uncertainty using the wild bootstrap method. The results show...
Evaluation of Non-linear Combination Method (Neural Network) For Value-at-Risk Forecasting in Market
, M.Sc. Thesis Sharif University of Technology ; Barakchian, Mahdi (Supervisor)
Abstract
Value at risk of an asset, is the asset’s expected maximum loss for a certain period of time and at a specified confidence level. Value-at-Risk can be calculated in the bank with its inter-nal method or standardized method. when a method have more violation number then bank need to keep more daily capital requirements. under the Basel 2 agreement if the violation of method more than 10 times in year, the Bank uses the standardized method.
There are trade off Between daily capital charge and violations. Therefore, existing methods for calculating the value at risk, usually lead to much daily capital charge or many violations. Studies show with combination of different methods to calculate...
There are trade off Between daily capital charge and violations. Therefore, existing methods for calculating the value at risk, usually lead to much daily capital charge or many violations. Studies show with combination of different methods to calculate...
Using Complex Network Metrics for Evaluating the Influence of Conference and Journal Papers in Computer Science
,
M.Sc. Thesis
Sharif University of Technology
;
Jalili, Mahdi
(Supervisor)
Abstract
Journals and conferences in computer science are the major venue for publishing new achievement in the field. It is an expert opinion that a number of top conferences in computer science are even more important than journals. In this work we aim at studying this in terms of citation analysis. To this end, we took 100 top journals and 63 top conferences and extracted their citation graph through Scopus dataset. We then constructed the citation graph in which the nodes were the journals and conferences and the links corresponded to the citations of the papers. We used various measures to rank the nodes in the graph. The ranking methods included Prestige, PageRank, Eigenfactor, HITS and SALSA....
Design and Implementation of a VLSI Architecture for Time and Frequency Synchronization in the LTE
, M.Sc. Thesis Sharif University of Technology ; Shabany, Mahdi (Supervisor)
Abstract
The long term evolution (LTE) standard is introduced and developed by the 3rd generation partnership project (3GPP) based on orthogonal frequency division multiplexing (OFDM). OFDM systems, in spite of having many advantages such high performance in bandwidth usage, are very sensitive to inter carrier interference (ICI) as a drawback. In order to prevent ICI, the frequency offset, mainly caused by the miss-match between oscillators' frequency and also between the sampling frequency of the transmitter and the receiver, should be estimated and compensated. Frequency synchronization is a part of the tasks of a synchronizer. In this thesis, main tasks of a synchronizer are illustrated and...