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ghasemi-zargar--alireza
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Simulation and Evaluating of Effective Parameters in Pedestrian-Vehicle Accident
, M.Sc. Thesis Sharif University of Technology ; Saadat Foumani, Mahmoud (Supervisor)
Abstract
Each year about 23 thousand people will be death in the road accidents in our country. According to the Legal Medicine Organization of Iran, about 24 percent of pedestrian fatalities in road accidents are the result of a collision with a car and because of that studying the different parameters that reduce pedestrian injury became an important issue to study. There are different techniques such as simulating crash tests on cadavers, experiments on pedestrian dummy and numerical simulation. The purpose of this project is simulating the car-pedestrian crash with numerical software called Madymo. Then optimize of the various parameters such as the height of the front bumper height, hood,...
Maximizing the Number of Adjacencies in a Multi Floor Facility Layout Problem with Unequal Rectangular Departments
, Ph.D. Dissertation Sharif University of Technology ; Ghasemi-Taromi, Farhad (Supervisor) ; Hajji, Alireza (Co-Advisor)
Abstract
Facility layout problem (FLP) is one of classical optimization problem in engineering science. The theoretical attractiveness and practical applications of the problem have created a rich literature in the FLP. There are varieties of measure of effectiveness’s for the FLPs, such as minimizing the space cost; minimizing the handing cost; maximizing the adjacencies; maximizing the safety and etc. Maximization of the adjacencies is a common measure of effectiveness, which is addressed in many related literatures especially, in continuous process facility layout. Using of the classical definition of the adjacency usually impose some restrictions on the layout designs. Due to these restrictions...
Malicious Network Flow Detection based on Behavioral Characteristics of Users
, M.Sc. Thesis Sharif University of Technology ; Jalili, Rasoul (Supervisor)
Abstract
Insider threat is a significant security risk for organizations and hard to detect. Most of introduced detection methods need contextual data entries about users, or preprocessed user activity logs to detect insider threats while it is costly and time-consuming. In this thesis, we introduce a behavior analysis method that learns its context and detects multiple types of insider threats from raw logs and network traffic in real-time. This method, named XABA, learns user roles and exclusive behaviors, through analyzing raw logs related to each network session of the user. Then it checks for some abnormal patterns, and if so, triggers the appropriate alert. XABA is implemented on the big-stream...
Nonlinear Microwave Circuits Design and Modeling using Behavioral Models Based on Volterra Series and X-parameter
, Ph.D. Dissertation Sharif University of Technology ; Banai, Ali (Supervisor)
Abstract
Modern microwave and wireless communications systems are too complex today to permit the complete simulation of the nonlinear behavior at the transistor level of description. This problem presents a significant productivity bottleneck for design engineers. At the bridge between the transistor circuit and the multichip module or RF integrated circuit (RFIC) we use “behavioral models” to describe the nonlinear circuit blocks or ICs in the system. The behavioral models are simplified models of the essential nonlinear behavior of the complex sub-circuits; this simplification means that these models will execute more quickly, and use much less memory than if an entire complex subsystem was...
An Estimation Model for Computation and Control of Trajectory Coverage Error in Additive Manufacturing
, M.Sc. Thesis Sharif University of Technology ; Houshmand, Mahmood (Supervisor)
Abstract
During 1980s Additive Manufacturing technologies for the purpose of prototyping with fast and less expensive, under the name of Rapid Prototyping was invented. But nowadays under the vast progress made in this field, it possesses a notable place in different industries such as automobile manufacturing, aerospace, architecture, medicine and so on for part manufacturing. In all AM machines, the CAD model design part is manufactured by adding layered to each other. In this research, at first by explaining manufacturing process and current different technologies, the place of this manufacturing process in today and future industry, is analyzed. For discussing replacement of this method instead...
Should methodological naturalists commit to metaphysical naturalism?
, Article Journal for General Philosophy of Science ; Volume 51, Issue 1 , 2020 , Pages 185-193 ; Azadegan, E ; Nabavi, L ; Sharif University of Technology
Springer
2020
Abstract
It is widely supposed that methodological naturalism, understood as a thesis about the methodology of science, is metaphysically neutral, and that this in turn guarantees the value-neutrality of science. In this paper we argue that methodological naturalism is underpinned by certain ontological and epistemological assumptions including evidentialism and the causal closure of the physical, adoption of which necessitates commitment to metaphysical naturalism. © 2019, Springer Nature B.V
Synthesis of Titanium Carbide Mxene-Carbonaceous Material Composite as Capacitive Deionization Electrode for Water Desalination
, M.Sc. Thesis Sharif University of Technology ; Khachatourian, Adrineh Malek (Supervisor)
Abstract
Capacitive deionization (CDI) is a suitable method for water desalination with low energy consumption and high efficiency, which does not have secondary pollution and is environmentally friendly. The hybrid capacitive deionization uses a faradaic electrode next to the carbonaceous electrode, taking advantage of both electrodes, and high capacities have also been reported. Titanium carbide Mxene is an important candidate in CDI due to its high electrical conductivity and tunable interlayer distance, but Mxene suffers from low oxidation resistance. Therefore, in this research, molybdenum disulfide (MoS2) that is an essential member of the 2D transition metal dichalcogenides family, was used as...
Spectrofluorimetric Determination of D-penicillamine Using FITC-capped Gold Nanoparticles Via Flourescence Resonance Energy Transfer Mechanism
, M.Sc. Thesis Sharif University of Technology ; Hormozi Nezhad, Mohammad Reza (Supervisor)
Abstract
Recently, fluorescence resonance energy transfer (FRET) based assay through employing gold nanoparticles have been developed for sensitive and selective detection of various analytes [1,2]. These are due to the extremely high extinction coefficient of Au NPs, which induces fluorescence quenching of the attached fluorophores as a result FRET ; a process which is inversely proportional to the sixth power of the distance between fluorophore and quencher [3]. Upon the addition of the analytes with much stronger affinity for Au NPs, the fluorophore molecules are detached from the surface of the Au NPs results in an increase of fluorescence intensity, which is in direct relation with...
A new double input-double output complex envelope amplifier behavioral model taking into account source and load mismatch effects
, Article IEEE Transactions on Microwave Theory and Techniques ; Volume 63, Issue 2 , 2015 , Pages 766-774 ; 00189480 (ISSN) ; Banai, A ; Pedro, J. C ; Sharif University of Technology
2015
Abstract
This paper presents a double input-double output bilateral low-pass equivalent amplifier behavioral model that takes into account input source and output load termination mismatches. The model is intended for the system-level simulation of amplifier chains subjected to wideband modulated signals, since it can predict the device's input and output scattered waves and their memory effects, in a wide range of voltage standing wave ratios (VSWR). In addition, the model extraction methodology, and its associated laboratory test bench are discussed, noting the limitations of conventional setups for behavioral model extraction and validation. The model is validated comparing the predicted and...
XABA: A zero-knowledge anomaly-based behavioral analysis method to detect insider threats
, Article 13th International ISC Conference on Information Security and Cryptology, 7 September 2016 through 8 September 2016 ; 2016 , Pages 26-31 ; 9781509039494 (ISBN) ; Nowroozi, A. R ; Jalili, R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
Insider threat is a significant security risk for organizations and hard to detect. Most introduced detection methods need contextual data entries about users, or preprocessed user activity logs to detect insider threats which it is costly and time-consuming. In this paper, we introduce a behavior analysis method that learns its context and detects multiple types of insider threats from raw logs and network traffic in real-time. This method, named XABA, learns user roles and exclusive behaviors, through analyzing raw logs related to each network session of the user. Then it checks for some abnormal patterns, and if so, triggers the appropriate alert. XABA is implemented on the big-stream...
Comparative Study of Ideal Scientific Community in Viewpoints of Nasr and Feyerabend
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Hassan (Supervisor) ; Taghavi, Mostafa (Supervisor)
Abstract
Today, several centuries after the time when science began to flourish of science, everybody is familiar with destroying consequences of modern science and technology, in addition to its achievments. Besides, domination and exclusive position of science in educational system and government organizations have marginalized alternative knowledge. Thus, some people found this trend dangerous for humankind’s fate and tried to change this situation. Nasr and Feyerabend are two philosophers that despite their different work area both criticise modern science and try to establish their own ideal scientific community.Nasr’s approach is regeneration of traditional science which was prevalent before...
An analytical approach to obtain optimum load impedance using X-parameters®
, Article 2012 Workshop on Integrated Nonlinear Microwave and Millimetre-Wave Circuits, INMMIC 2012 ; 2012 ; 9781467329491 (ISBN) ; Banai, A ; Cai, J ; Brazil, T ; Sharif University of Technology
2012
Abstract
This paper introduces an analytical approach to obtain fundamental and harmonic load-pull contours using X-parameters. This method is proposed to obtain the optimum load impedance at different harmonics. This approach has been applied on a two port X-parameter model and its results are independently verified by ADS simulation
DIDO behavioral model extraction setup using uncorrelated envelope signals
, Article European Microwave Week 2015: "Freedom Through Microwaves", EuMW 2015 - Conference Proceedings; 2015 45th European Microwave Conference Proceedings, EuMC, 7 September 2015 through 10 September 2015 ; 2015 , Pages 646-649 ; 9782874870392 (ISBN) ; Banai, A ; Pedro, J. C ; APS ; Sharif University of Technology
2015
Abstract
This work discusses several extraction procedures for the recently proposed dual input-dual output (DIDO) low pass equivalent behavioral model according to their required excitation signals. These methods are based on passive load pulling and uncontrolled open loop active load pulling but with different type of excitation waveforms. It also addresses the hardware and signal conditioning of the proposed extraction procedures in detail. The performance of the discussed methods are compared based on the datasets extracted from simulation results in ADS. The results show that the use of the active load-pulling can enhance modeling performance
Transmission Expansion Planning Considering Network Topology Optimization
, M.Sc. Thesis Sharif University of Technology ; Fotuhi-Firuzabad, Mahmud (Supervisor)
Abstract
With increasing demand levels in recent years, transmission congestion is considered as one of the most important power system constraints. This limitation can result in higher operational costs and load curtailment. Furthermore, in power systems with high penetration of wind power, a significant amount of wind curtailment may occur due to congestion of transmission lines. Thus, in order to guarantee a reliable and economic operation of the power system, new transmission lines should be constructed with a rational plan. Very high investment costs are required for building new transmission lines to meet the growing demand. This fact as well as the other associated difficulties emphasize the...
Impact of reliability considerations on network topology optimization
, Article 26th Iranian Conference on Electrical Engineering, ICEE 2018, 8 May 2018 through 10 May 2018 ; 2018 , Pages 1215-1220 ; 9781538649169 (ISBN) ; Fotuhi Firuzabad, M ; Farzin, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
Optimal transmission switching (OTS) along with optimal bus-bar switching, also known as network topology optimization (NTO), has been previously proposed and utilized as a powerful tool to reduce operational costs. However, operational constraints and reliability considerations of NTO problem have not been addressed properly. In this paper, operational constraints are integrated in NTO problem and the effect of transmission network switching on expected interruption cost (EIC) is investigated. Moreover, a novel approach based on pool of solutions approach is presented, which can generate various switching scenarios. In doing so, the decision maker would be able to analyze and choose the...
Effect of nanoparticle behaviour on mud cake buildup for directional and horizontal wells: mathematical modelling and experimental study
, Article Journal of Experimental Nanoscience ; Volume 11, Issue 12 , 2016 , Pages 975-999 ; 17458080 (ISSN) ; Ghazanfari, M. H ; Shahbazi, K ; Zargar, G ; Sharif University of Technology
Taylor and Francis Ltd
2016
Abstract
The present study examined the effect of nanoparticle size and geometry on filter cake buildup during dynamic filtration using experimental and modeling approaches. A dynamic filtration setup was proposed and designed to test cross-flow circulation against a synthetic core at a constant differential pressure. The proposed mathematical model considers the critical deposition boundary of the porous media for particles along with drag, lift, friction, buoyancy, permeate, and electrostatic forces. The comprehensive model response allowed investigation of the aggregation and shape of nanoparticles at different cross-flow inclinations. The drag and lift force coefficients and moment of inertia of...
The impact of nanoparticles geometry and particle size on formation damage induced by drilling nano-fluid during dynamic filtration
, Article Journal of Nano Research ; Volume 43 , 2016 , Pages 81-97 ; 16625250 (ISSN) ; Shahbazi, Kh ; Ghazanfari, M. H ; Zargar, Gh ; Sharif University of Technology
Trans Tech Publications Ltd
2016
Abstract
In this paper, the impact of three parameters including nanoparticles geometry, particles aggregation and borehole inclination on induced formation damage from water based drilling fluids were investigated by means of experimental studies. Accordingly, we designed a dynamic filtration setup capable to rotate and change well inclination. Nano-based drilling fluids consisting of spherical, cubical and tubular shapes nanoparticles as fluid loss additives were used. Mud cake quality, core permeability impairment and degree of formation damage at various well inclinations were examined. The cluster structure of aggregated particles were determined using fractal theory and applying dynamic light...
Experimental investigation of self-repeating effect of different nanoparticles on internal mud cake formation by water-based drilling fluid in directional wells
, Article IADC/SPE Asia Pacific Drilling Technology Conference 2016, 22 August 2016 through 24 August 2016 ; Volume 2016-January , 2016 ; 9781613994504 (ISBN) ; Shahbazi, K ; Ghazanfari, M. H ; Zargar, G ; Sharif University of Technology
Society of Petroleum Engineers (SPE)
2016
Abstract
In this paper, the impact of three parameters including nanoparticles geometry, particles aggregation and borehole inclination on induced formation damage from water based drilling fluids were investigated by means of experimental studies. Accordingly, we designed a dynamic filtration setup capable to rotate and change well inclination. Nano-based drilling fluids consisting of spherical, cubical and tubular shapes nanoparticles as fluid loss additives were used. Mud cake quality, core permeability impairment and degree of formation damage at various well inclinations were examined. The cluster structure of aggregated particles were determined using fractal theory and applying dynamic light...
Experimental investigation of self-repeating effect of different nanoparticles on internal mud cake formation by water-based drilling fluid in directional wells
, Article Drilling Technology Conference 2016, 22 August 2016 through 24 August 2016 ; 2016 ; 9781613994504 (ISBN) ; Shahbazi, K ; Ghazanfari, M. H ; Zargar, G ; Sharif University of Technology
Society of Petroleum Engineers
2016
Abstract
In this paper, the impact of three parameters including nanoparticles geometry, particles aggregation and borehole inclination on induced formation damage from water based drilling fluids were investigated by means of experimental studies. Accordingly, we designed a dynamic filtration setup capable to rotate and change well inclination. Nano-based drilling fluids consisting of spherical, cubical and tubular shapes nanoparticles as fluid loss additives were used. Mud cake quality, core permeability impairment and degree of formation damage at various well inclinations were examined. The cluster structure of aggregated particles were determined using fractal theory and applying dynamic light...
Parallelized numerical modeling of the interaction of a solid object with immiscible incompressible two-phase fluid flow
, Article Engineering Computations (Swansea, Wales) ; Volume 34, Issue 3 , 2017 , Pages 709-724 ; 02644401 (ISSN) ; Nikbakhti, R ; Ghasemi, A ; Hedayati, F ; Malvandi, A ; Sharif University of Technology
2017
Abstract
Purpose - A numerical method is developed to capture the interaction of solid object with two-phase flow with high density ratios. The current computational tool would be the first step of accurate modeling of wave energy converters in which the immense energy of the ocean can be extracted at low cost. Design/methodology/approach - The full two-dimensional Navier-Stokes equations are discretized on a regular structured grid, and the two-step projection method along with multi-processing (OpenMP) is used to efficiently solve the flow equations. The level set and the immersed boundary methods are used to capture the free surface of a fluid and a solid object, respectively. The full...