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bahrami--bahador
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Examining the Relationship Between Post-choice Attitude Change and Framing Effects
, M.Sc. Thesis Sharif University of Technology ; Fatemi, Farshad (Supervisor) ; Bahrami, Bahador (Supervisor)
Abstract
In economics, choice or behavior is considered as a result of utility optimization. However, there’s much theoretical and experimental evidence that shows human beings suffer from decision-making and judgment errors. This research aiming at examining the relationship between post-choice attitude changes and framing effects as the two instances of those errors designed and implemented a 2 by 2 between-subject lab experiment. The subjects were randomly assigned to one of these four groups. The two treatment groups made their decision after they rated the objects one time and the two control groups did this after they evaluated the objects two times. Another intervention was to manipulate...
Reliability of slope stability analysis using fuzzy set
, Article Annual Conference of the Canadian Society for Civil Engineering 2007: Where the Road Ends, Ingenuity Begins, Yellowknife, NT, 6 June 2007 through 9 June 2007 ; Volume 1 , 2007 , Pages 11-20 ; Sharif University of Technology
2007
Abstract
In this research, theory of fuzzy sets is used to deal with the uncertain nature of soil parameters and the inaccuracy involved in the analysis simultaneously. Soil parameters are defined using suitable fuzzy sets and the uncertainty inherent in the value of factor of safety is assessed. It is believed that this approach accounts for the uncertainty in soil parameters more realistically compared to the conventional probabilistic approaches reported in the literature. The proposed method is applied to a case study and the results are discussed subsequently
Small-strain shear modulus of cement-admixed kaolinite
, Article Geotechnical and Geological Engineering ; Volume 30, Issue 1 , Oct , 2012 , Pages 163-171 ; 09603182 (ISSN) ; Pak, A ; Sharif University of Technology
2012
Abstract
An experimental study is conducted to measure small-strain shear modulus of clay-cement mixture using bender element apparatus setup in a triaxial cell. Bender element tests were conducted on cement-treated soils and the results were analyzed to study the variation of shear modulus properties of soil specimens at different cement contents, confining pressures, curing times, and compaction moisture contents. Based on the obtained results increasing the cement ratio has a significant effect on the small-strain shear modulus of the treated soils, and this effect signifies with increasing the moisture content and curing time. Rates of shear modulus enhancements due to cement content, curing...
Simplified Methods to Estimate the Response of Non-linear Soil-structure Interaction Systems
, M.Sc. Thesis Sharif University of Technology ; Ghannad, Mohammad Ali (Supervisor)
Abstract
Usually the structures are designed based on the fixed-base assumption; however thisassumption is not always correct and the bed flexibility should be considered. This effectwhich is called soil-structure interaction, change the response of structure on both elasticand inelastic behavior. In the regulations for the design of structures on flexible base,generally soil-structure system is replaced with an equivalent fixed base structure; in theway that the design force of soil-structure system with reasonable accuracy can beestimated by equivalent fixed-base structure. In some regulations, dynamic characteristicsof equivalent structure have been determined on elastic state and the results have...
Damage Detection of Offshore Jacket Platforms Using Fitting Vibration Data
, M.Sc. Thesis Sharif University of Technology ; Ali Akbar, Golafshani (Supervisor)
Abstract
In the regard of structural health monitoring the identification of the structural modal parameters is essential. Since the different sources (wind, waves, Devices …) induce vibration on an offshore platform, it is impossible to determine the portion of each source in vibration. Thus the methods that analyze vibrations needless of input measurements are more efficient. These methods apply the ambient factors and obtain the modal properties from the structural response. This procedure has no unwanted effect on the serviceability of structure and by placement of sensors on the platform; one can monitor the structural health.
In the present work a two dimensional jacket offshore platform...
In the present work a two dimensional jacket offshore platform...
Economic complexity and the dynamics of regional competitiveness a systematic review
, Article Competitiveness Review ; Volume 33, Issue 4 , 2023 , Pages 711-744 ; 10595422 (ISSN) ; Shahmoradi, B ; Noori, J ; Turkina, E ; Bahrami, H ; Sharif University of Technology
Emerald Publishing
2023
Abstract
Purpose: This study aims to systematically review the economic complexity literature to advance the knowledge on its contribution to building regional competitiveness. Design/methodology/approach: In this study, we did a systematic review of 111 relevant papers. In this regard, we did a thematic analysis on all the collected papers, which led to a two-level processed approach. In the first level, the contributions of the reviewed articles have been classified into three main streams. In the second level, the findings under each contribution category are analyzed and explained. This approach led to a thematic network demonstrating economic complexity and the dynamics of regional...
Game theoretic based charging strategy for plug-in hybrid electric vehicles
, Article IEEE Transactions on Smart Grid ; Vol. 5,Issue. 5 , 2014 , pp. 2368-2375 ; ISSN: 19493053 ; Parniani, M ; Sharif University of Technology
2014
Abstract
In the future smart grids, Plug-in Hybrid Electric Vehicles (PHEVs) are seen as an important means of transportation to reduce greenhouse gas emissions. One of the main issues regarding to this sort of vehicles is managing their charging time to prevent high peak loads over time. Deploying advanced metering and automatic chargers can be a practical way not only for the vehicle owners to manage their energy consumption, but also for the utilities to manage the electricity load during the day by shifting the charging loads to the off-peak periods. Additionally, an efficient charging schedule can reduce the users' electricity bill cost. In this paper we propose a new practical demand response...
Stability of chiral states, role of intermolecular interactions and molecular parity violation
, Article Computational and Theoretical Chemistry ; Volume 978, Issue 1-3 , 2011 , Pages 84-87 ; 2210271X (ISSN) ; Shafiee, A ; Sharif University of Technology
2011
Abstract
We study the problem of stability of chiral states, also known as problem of chirality, within the framework of a two-dimensional approximation of a symmetric double-well potential. We show how the symmetry breaking of the potential due to the molecular parity violation can stop the tunneling in a coherent way, accordingly stabilize the chiral states. Then, we use the quantum Brownian motion within a linear Lindblad-type equation to model how the intermolecular interactions make the tunneling incoherent, thus inducing a racemization by dephasing. Finally, we investigate the normal physical conditions where the dephasing racemization does not suppress the effects of the molecular parity...
Tunneling properties of nonplanar molecules in a gas medium
, Article Physical Review A - Atomic, Molecular, and Optical Physics ; Volume 84, Issue 6 , 2011 ; 10502947 (ISSN) ; Bassi, A ; Sharif University of Technology
2011
Abstract
We propose a simple, general, and accurate formula for analyzing the tunneling between classical configurations of a nonplanar molecule in a gas medium, as a function of the thermodynamic parameters of the gas. We apply it to two interesting cases: (i) the shift to zero frequency of the inversion line of ammonia, upon an increase in the pressure of the gas; and (ii) the destruction of the coherent tunneling of D 2S 2 molecules in a He gas. In both cases, we compare our analysis with previous theoretical and experimental results
Circuit design to improve security of telecommunication devices
, Article 2015 IEEE Conference on Technologies for Sustainability, SusTech 2015, 30 July 2015 through 1 August 2015 ; Aug , 2015 , Pages 171-175 ; 9781479918010 (ISBN) ; Hajsadeghi, K ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
Security in mobile handsets of telecommunication standards such as GSM, Project 25 and TETRA is very important, especially when governments and military forces use handsets and telecommunication devices. Although telecommunication could be quite secure by using encryption, coding, tunneling and exclusive channel, attackers create new ways to bypass them without the knowledge of the legitimate user. In this paper we introduce a new, simple and economical circuit to warn the user in cases where the message is not encrypted because of manipulation by attackers or accidental damage. This circuit not only consumes very low power but also is created to sustain telecommunication devices in aspect...
Rigid body attitude control with delayed attitude measurement
, Article IEEE Transactions on Control Systems Technology ; Volume 23, Issue 5 , February , 2015 , Pages 1961-1969 ; 10636536 (ISSN) ; Namvar, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
Time delay in the evaluation of the attitude of a rigid body can significantly hinder the performance of the attitude control system. In this brief, we propose a dynamically smooth control law that guarantees asymptotic convergence of the rigid body attitude and angular velocity to their desired values in the presence of delayed attitude measurement. We assume that the moment-of-inertia matrix of the body is unknown. The control law includes a matrix gain that is computed by solving a delay-dependent and time-varying matrix differential equation. It is shown that the solvability of the matrix differential equation depends on a uniform controllability condition, which can be verified a priori...
Motion tracking in robotic manipulators in presence of delay in measurements
, Article Proceedings - IEEE International Conference on Robotics and Automation, 3 May 2010 through 7 May 2010, Anchorage, AK ; 2010 , Pages 3884-3889 ; 10504729 (ISSN) ; 9781424450381 (ISBN) ; Namvar, M ; Sharif University of Technology
2010
Abstract
Time-delay in sensor measurements can be a frequent cause of instability and performance degradation in a robotic system. In this paper, motion tracking of rigid manipulators in presence of constant and known delay in sensors is investigated. By using non-minimal model of a manipulator, a dynamically smooth controller based on the Linear Matrix Inequality (LMI) approach is proposed which guarantees asymptotic tracking of desired joint angles and velocities in presence of delayed measurements. For a given controller the maximum amount of delay that preserves system stability is computed by solving an LMI optimization and also by numerical simulations, and the results are compared. Finally, a...
From demand response in smart grid toward integrated demand response in smart energy hub
, Article IEEE Transactions on Smart Grid ; Volume 7, Issue 2 , 2016 , Pages 650-658 ; 19493053 (ISSN) ; Sheikhi, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
The proliferation of technologies such as combine heat and power systems has accelerated the integration of energy resources in energy hubs. Besides, the advances in smart grid technologies motivate the electricity utility companies toward developing demand response (DR) programs to influence the electricity usage behavior of the customers. In this paper, we modify the conventional DR programs in smart grid to develop an integrated DR (IDR) program for multiple energy carriers fed into an energy hub in smart grid, namely a smart energy (S. E.) hub. In our model, the IDR program is formulated for the electricity and natural gas networks. The interaction among the S. E. hubs is modeled as an...
SN transport method for neutronic noise calculation in nuclear reactor systems: comparative study between transport theory and diffusion theory
, Article Annals of Nuclear Energy ; Volume 114 , 2018 , Pages 236-244 ; 03064549 (ISSN) ; Vosoughi, N ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
In this paper, the neutron noise based on transport theory and diffusion noise theory using Green's function technique is calculated. As the neutron noise is used for core diagnostic, surveillance and monitoring, calculation of neutron noise precisely can play an important role in monitoring and safety. We compare the accuracy of Green's function based on transport and diffusion theory in order to survey the differences between these theories. In this study some deviation between results obtained two theories are observed, and the impact of dimensions, cross sections and frequency on the results investigated. © 2017
Circuit design to improve security of telecommunication devices
, Article 2017 IEEE 7th Annual Computing and Communication Workshop and Conference, CCWC 2017, 9 January 2017 through 11 January 2017 ; 2017 ; ISBN: 978-150904228-9 ; Hajsadeghi, K ; Sharif University of Technology
2017
Abstract
Security in mobile handsets of telecommunication standards such as GSM, Project 25 and TETRA is very important, especially when governments and military forces use handsets and telecommunication devices. Although telecommunication could be quite secure by using encryption, coding, tunneling and exclusive channel, attackers create new ways to bypass them without the knowledge of the legitimate user. In this paper we introduce a new, simple and economical circuit to warn the user in cases where the message is not encrypted because of manipulation by attackers or accidental damage. This circuit not only consumes very low power but also is created to sustain telecommunication devices in aspect...
A novel organic–inorganic hybrid tandem solar cell with inverted structure
, Article Applied Physics A: Materials Science and Processing ; Volume 123, Issue 4 , 2017 ; 09478396 (ISSN) ; Faez, R ; Sharif University of Technology
Springer Verlag
2017
Abstract
A novel organic–inorganic hybrid tandem solar cell with inverted structure is proposed. This efficient double-junction hybrid tandem solar cell consists of a single-junction hydrogenated amorphous silicon (a-Si:H) subcell with n-i-p structure as front cell and a P3HT:PCBM organic subcell with inverted structure as back cell. In order to optimize the hybrid tandem cell, we have performed a simulation based on transfer matrix method. We have compared the characteristics of this novel structure with a conventional structure. As a result, a power conversion efficiency (PCE) of 6.1 and 24% improvement compared to the conventional hybrid tandem cell was achieved. We also discuss the high potential...
Global attitude estimation using single delayed vector measurement and biased gyro
, Article Automatica ; Volume 75 , 2017 , Pages 88-95 ; 00051098 (ISSN) ; Namvar, M ; Sharif University of Technology
2017
Abstract
Time delay in attitude determination systems is unavoidable and it is usually caused by low-quality data sampling, poor sensor synchronization, momentary sensor outage or operational restrictions of sensors. Despite its performance-degrading effect, time delay has been widely neglected in the existing attitude estimation methods. This paper presents a general framework for design of attitude estimators with and without SO(3) manifold restriction by assuming that measurement of a single vector measurement is available with time delay. Also, measurement of rigid-body angular velocity is considered available with an unknown bias. The proposed estimator guarantees global and asymptotic...
A new approach for calculation of the neutron noise of power reactor based on Telegrapher's theory: Theoretical and comparison study between Telegrapher's and diffusion noise
, Article Nuclear Engineering and Technology ; Volume 52, Issue 4 , 2020 , Pages 681-688 ; Vosoughi, N ; Sharif University of Technology
Korean Nuclear Society
2020
Abstract
The telegrapher's theory was used to develop a new formulation for the neutron noise equation. Telegrapher's equation is supposed to demonstrate a more realistic approximation for neutron transport phenomena, especially in comparison to the diffusion theory. The physics behind such equation implies that the signal propagation speed is finite, instead of the infinite as in the case of ordinary diffusion. This paper presents the theory and results of the development of a new method for calculation of the neutron noise using the telegrapher's equation as its basis. In order to investigate the differences and strengths of the new method against the diffusion based neutron noise, a comparison was...
Simulation analysis of inverted organic solar cells with grating structure: undesirable effects of high absorption near grating anode
, Article Optik ; Volume 154 , February , 2018 , Pages 453-458 ; 00304026 (ISSN) ; Faez, R ; Sharif University of Technology
Elsevier GmbH
2018
Abstract
An inverted organic solar cell (IOSC) with nanograting array as anode of the cell has been simulated and analyzed using a combined electrical and optical approach. We have used finite difference time domain (FDTD) method for optimizing device structure. We have compared the characteristics of the IOSC with grating structure with a reference IOSC without grating structure. As a result, an improvement of 11% and 26% in power conversion efficiency (PCE) and short circuit current (JSC) compared to the reference structure was achieved. An analysis is provided on the origin of reduced fill factor (FF) in the IOSC with grating structure. We also have discussed about disadvantage of using optical...
Application of temperature transient analysis in well test interpretation for gas wells
, Article Petroleum Engineers - SPE Asia Pacific Oil and Gas Conference and Exhibition 2007 "Resources, Professionalism, Technology: Time to Deliver"30 October 2007 through 1 November 2007Code 73703 ; Volume 2 , 2007 , Pages 643 - 655 ; 9781604238594 (ISBN) ; Siavoshi, J ; Sharif University of Technology
2007
Abstract
During transient tests, both pressure and temperature are changed depending on downhole flow rate. In gas producing wells, Joule-Thomson cooling and frictional heating effects are the main dynamic factors causing flowing bottomhole temperature to differ from the static formation temperature at that depth. When a gas well is shut in, JT cooling effect is vanished and this causes a sharp increase in sandface temperature. As effect of wellbore storage ends, wellbore temperature gradually cools down due to heat conduction with near wellbore region. This paper demonstrates a new technique for using temperature transient data in gas wells in order to determine end of wellbore storage. Also, effect...