Investigation into the Effects of Using Various Thermal Insulators on the Behaviour of Structural Connections During Fire

, M.Sc. Thesis Sharif University of Technology Jamshidi Vismeh, Alireza (Author) ; Khonsari, Vahid (Supervisor)

Abstract

Steel is a non-combustible material, but at high temperatures, steel structures, due to their diminishing yield strength, undergo a considerable visco-plastic deflection, which results in a reduction in their load bearing capacity. Thus, to increase safety against fire must be considered as an important objective in the design and construction of steel structures. One of the safety measures which can be taken against fire is to increase the resistance of the structure against heat by using heat-resistant coatings. This decreases the rate of transfer of heat to the structure, and must include the ‘structural members’ and ‘structural joints’. Due to the role of structural connections in...

Asphaltene aggregation under the influence of structural features and interaction energies: Combination of quantum mechanical and molecular dynamics approaches

, Article Colloids and Surfaces A: Physicochemical and Engineering Aspects ; Volume 671 , 2023 ; 09277757 (ISSN) Vahid Dastjerdi, M ; Sayahi, H ; Koochaki, A ; Jamshidi, Z ; Sharif University of Technology

Elsevier B.V 2023

Abstract

The importance of the model to predict the aggregation behavior of asphaltene molecules at the molecular level was well established in different studies. Elucidation of the relationship between the interaction energy and the structural characteristics of asphaltene molecules to their aggregation behavior still needs further investigation. For this purpose, we combined the quantum mechanics and molecular dynamics approaches and analyzed the interaction energy of asphaltene to find out the effect of structural features on the aggregation behavior. The interaction energy of asphaltene is used in this study to evaluate the potential of aggregation. We found that asphaltene molecules with smaller...

Development of a New Simulation Tool to Study the Asphaltene Precipitation and Deposition in Oil Well Column Based on Particle Scaling

, M.Sc. Thesis Sharif University of Technology Naseri Boroujeni, Saman (Author) ; Jamshidi, Saied (Supervisor) ; Taghikhani, Vahid (Supervisor)

Abstract

Formation, precipitation and deposition of heavy organic compounds of petroleum fluids including, but not limited to, asphaltene in oil reservoirs and production systems have been by far the most important and challenging flow assurance problems. Therefore, preventative actions to control organic deposits in oil formations and production systems which can lead inevitably to reduction or cessation in production, have always been a main challenge for oil producers.In this thesis, a one dimensional simulator have been developed to study asphaltene precipitation, aggregation and deposition in an oil well column at isothermal and non-isothermal conditions. While the previously proposed PC-SAFT...

A Model for Effects of Hole Cleaning on Pipe Sticking by Considering Well, Fluid and Cutting Concentration Condition

, M.Sc. Thesis Sharif University of Technology Mousavi, Rahmatolah (Author) ; Taghikhani, Vahid (Supervisor) ; Jamshidi, Saeed (Co-Supervisor)

Abstract

Poor hole cleaning while drilling due to problems such as pipe sticking and ROP reducing will increase drilling cost. It is almost impossible to optimize the hole cleaning during the well planning due to the large number of effective parameters, so it is very important to monitor the hole cleaning conditions while drilling. The best way to monitor the well condition during drilling is using the real time drilling data (RTDD). Hook load (HKL) is one of many RTDD parameters that measured at the surface during drilling operations so it can be used to evaluate the hole cleaning condition. In this research, how to process the raw data recorded while drilling has been investigated. In the next...

Wel Test Analysis Using Deconvolution Method in Naturally Fractured
Reservoirs

, M.Sc. Thesis Sharif University of Technology Soleimani, Payam (Author) ; Taghikhani, Vahid (Supervisor) ; Shadizadeh, Seyed Reza (Supervisor) ; Jamshidi, Saeid (Co-Advisor)

Abstract

Wellbore storage effect is one of the biggest problems of petroleum engineers in analyzing the reservoir properties. In this phenomenon, at the beginning time of production from a reservoir, the fluid is initially produced from the well and not from the reservoir. Due to this effect, the pressures are distorted and could not be used in reservoir analysis. In this thesis the wellbore storage effect would be removed in naturally fractured reservoirs using deconvolution method. Using this method the range of data used could be increased. In this method special techniques are used in order to determine reservoir behaviour.
Using the method presented in this thesis, petroleum engineers could...

Performance analysis of spectral-phase-encoded optical CDMA system using two-photon-absorption receiver structure for asynchronous and slot-level synchronous transmitters

, Article Journal of Lightwave Technology ; 2007, Volume 25, Issue 6, Pages 1638-1645 Jamshidi, K ; Salehi, J. A ; Sharif University Of Technology

Abstract

In this paper, we analyze the performance of a nonlinear two-photon-absorption (TPA) receiver and compare its performance with that of a single-photon-absorption (SPA) receiver in the context of spectral-phase-encoded optical code-division multiple access (CDMA) technique. The performances for the above systems are evaluated for two different transmission scenarios, namely, asynchronous and slot-level synchronous transmitters. Performance evaluation includes different sources of degradation such as multiple-access interference, noise due to optical amplification, shot noise, and thermal noise. In obtaining the performance, the mean and variance of the received signal in each of the above...

Statistical characterization and the bit- error- rate analysis of lightwave systems with optical amplification using two-photon absorption receiver structures

, Article IEEE/OSA Journal of Lightwave Technology ; 2006 Vol. 24, Issue 3, PP. 1302-1316 Jamshidi, K ; Salehi, J. A ; Sharif University Of Technology

Abstract

In this paper, the authors study the performance of a two-photon absorption (TPA) receiver in a typical communication system employing an optical amplifier. For the study, the authors develop a comprehensive performance analysis, taking into account noises due to an optical amplifier, shot noise, and thermal noise, using Gaussian approximation technique. In evaluating the performance of the system using this technique, the mean and the variance of the received signal will be derived. Comparing the results of receivers using the TPA process with that of a typical single-photon absorption (SPA) structure leads the authors to conclude that TPA receivers can be used when the speed of the...

Statistical analysis of coherent ultrashort light pulse CDMA with multiple optical amplifiers using additive noise model

, Article IEEE/OSA Journal of Lightwave Technology ; Vol. 23, No. 5, PP. 1842-1851, May 2005 Jamshidi, K ; Salehi, J. A ; Sharif University Of Technology

Abstract

This paper describes a study of the performance of various configurations for placing multiple optical amplifiers in a typical coherent ultrashort light pulse code-division multiple access (CULP-CDMA) communication system using the additive noise model. For this study, a comprehensive performance analysis was developed that takes into account multiple-access noise, noise due to optical amplifiers, and thermal noise using the saddle-point approximation technique. Prior to obtaining the overall system performance, the input/output statistical models for different elements of the system such as encoders/decoders, star coupler, and optical amplifiers were obtained. Performance comparisons...

Optimal design of two-dimensional porosity distribution in shear deformable functionally graded porous beams for stability analysis

, Article Thin-Walled Structures ; Volume 120 , 2017 , Pages 81-90 ; 02638231 (ISSN) Jamshidi, M ; Arghavani, J ; Sharif University of Technology

2017

Abstract

In the present study, considering two-dimensional porosity distribution through a functionally graded porous (FGP) beam, its optimal distributions are obtained. A multi-objective optimization problem is defined to maximize critical buckling load and minimize mass of the beam, simultaneously. To this end, Timoshenko beam theory is employed and equilibrium equations for two-dimensional functionally graded porous (2D-FGP) beam are derived. For the solution, we present generalized differential quadrature method (GDQM) and consider two symmetric boundary conditions (Clamped-Clamped and Hinged-Hinged). Solving generalized eigenvalue problem, critical buckling load for 2D-FGP beam is then obtained....

Optimal material tailoring of functionally graded porous beams for buckling and free vibration behaviors

, Article Mechanics Research Communications ; Volume 88 , 2018 , Pages 19-24 ; 00936413 (ISSN) Jamshidi, M ; Arghavani, J ; Sharif University of Technology

Elsevier Ltd 2018

Abstract

In this paper, assuming porosity varies only along thickness direction, its optimal distributions in functionally graded porous (FGP) beams are tailored. Two multi-objective optimization problems are defined. In the first one, critical buckling load and mass are optimized simultaneously while in the second one, we concentrate on simultaneous optimization of mass and fundamental frequency. Employing Timoshenko beam theory, we present governing equations for a FGP beam. For the solution, we use Ritz method and propose appropriate trial functions according to the boundary conditions (Hinged-Hinged, Clamped-Clamped, Clamped-Hinged and Clamped-Free). Since the porosity distribution along...

On the dissemination of the discourse of going: The case of Iranian for-profit study abroad institution's chronotopic representation of ideal life there

, Article Language and Communication ; Volume 80 , September , 2021 , Pages 11-24 ; 02715309 (ISSN) Jamshidi, S ; Rezaei, S ; Sharif University of Technology

Elsevier Ltd 2021

Abstract

This research addresses the escalation of the ‘discourse of going’ among Iranian educated people in recent years through highlighting the influential role played by for-profit study abroad institutions. Utilizing a discourse-analytic approach, we engage the theoretical concept of chronotope, caliberation, and commodification to investigate the ways through which for-profit study abroad institutions represent the images of ‘life beyond’. The data were obtained in interview sessions with ten certified Iranian study-abroad institutions. The results of the data analysis revealed two main themes, namely, hypothetical utopia there and dystopia here as well as success here-and-now and...

Security Evaluation of Public Key Based Key Management in MANET

, M.Sc. Thesis Sharif University of Technology Jamshidi, Farzad (Author) ; Mohajeri, Javad (Supervisor)

Abstract

Due to popularity of mobile wireless devices, security of mobile ad hoc networks (MANETs) being more important than before. Traditional key management schemes based on symmetric key cryptography are became ineffective because of dynamic and infrastructureless nature of these networks.Recent studies are mainly based on traditional public key cryptography schemes and ID-based cryptography schemes. On the other hand, Contributory schemes seem suitable for MANETs because of their inherent self-organize property. Key update and Key revocation are the fundamental issues of key management schemes in mobile ad hoc networks. Certificateless public key cryptography, in addition to solve those issues,...

Application of Pore Network Modeling in Study of Rock Typing Algorithms

, M.Sc. Thesis Sharif University of Technology Sistan, Morteza (Author) ; Jamshidi, Saeed (Supervisor)

Abstract

One of the most important issues in modeling and simulation of reservoirs is determination of different rock types or Rock Typing. In this study, after a brief review of some conventional methods for rock typing, their capabilities have been investigated. In this way, for the first time, pore network modeling is used as a tool for validating the rock typing methods. By using flow simulation in porous medium with pore network modeling approach, similar rock types data have been generated and these artificially data have been used for validating of rock typing methods. To form more realistic pore networks, both regular and irregular pore network have been modeled and analyzed. Pore size...

Sensitivity Analysis in Total Search Domain and Automatic Selection of the Most Sensitive Matching Parameters in Tuning of EOS and History Matching

, M.Sc. Thesis Sharif University of Technology Chenani, Ahmad (Author) ; Jamshidi, Saeed (Supervisor)

Abstract

One of the major issues raised in the numerical models is the effects of various input parameters on the model output. Identifying the most important parameters in the output is very important in petroleum engineering, especially in tuning equation of states and history matching. Screening the most important parameters from unimportant parameters is assessable by sensitivity analysis.In this study local and global sensitivity analysis methods are used to identify the most important parameters in tuning EOS for seven different fluid samples. Global sensitivity analysis methods are more successful in correct ranking of tuning parameters. Morris method as a global method can screen the...

Study of ESP and Gas Lift Applications On low Productivity Wells of Alvand Oil Field

, M.Sc. Thesis Sharif University of Technology Pornouri, Pouria (Author) ; Jamshidi, Saeed (Supervisor)

Abstract

Alavand Oil field is located 50 Km away from west of Siri Island and includes DPG and DPH platforms. The production from Alavand field started in 1998 and till now 11 wells have been totally drilled .Since a production peak in 2001, the oil production in Alvand field has decreased. Water cut is increasing and reservoir pressure is decreasing gradually. Considering poor reservoir characteristic of this reservoir, productivity indexes of wells are relatively low. In addition; natural depletion of reservoir caused the wells to be unable to flow naturally and either closed or produce periodically consequently. To increase production and extend the lifetime of Alvand field, it is decided to start...

Modelling Point and non Point Source of Nitrate with SWAT in the Jajrood River Watershed

, M.Sc. Thesis Sharif University of Technology Jamshidi, Mahdi (Author) ; Tajrishy, Masoud (Supervisor)

Abstract

To investigate boiling heat transfer characteristics of nanofluids, transient quenching¬ experiments of a high temperature silver sphere in water-based nanofluids with Ag and TiO2 nanoparticles were performed. A silver sphere of 10 mm in diameter at the initial temperature of 700o C was quenched in the nanofluids at the temperature of 90o C. The results showed considerable reduction in the quenching ability of nanofluids compared to that of pure water. The presence of nanoparticles in water caused film boiling mode to vanish at lower temperatures depending on the mixture concentration. Computed heat transfer rates in nanofluids were lower than those in pure water. In the quenching...

Pore scale acidizing Simulation Using Lattice Boltzmann Method

, M.Sc. Thesis Sharif University of Technology Asghari, Mohammad (Author) ; Jamshidi, Saeed (Supervisor)

Abstract

Matrix acidizing aims at bypassing near wellbore damages in typical carbonate reservoirs or enhancing permeability and hydraulic conductivity in naturally fracture ones. The simulation of acidizing process at pore scale and complex geometries by LBM will lead to gain more knowledge about molecular mechanisms that govern rock dissolution, diffusion and advection of reactive fluid and help the evaluation of acidizing efficiency.In this thesis, simulation of acidizing includes the following steps:
• Multicomponent fluid convection
• Fluid diffusion into the solid
• Fluid-rock reaction
• Boundary conditions including periodic, bounceback, non-equilibrium bounceback, Dirichlet,...

On the Effects of Background Electromagnetic elds and Chiral Chemical Potential on the Phase Diagram of Quantum Chromodynamics

, M.Sc. Thesis Sharif University of Technology Jamshidi, Abdollah (Author) ; Sadooghi, Neda (Supervisor)

Abstract

In particle physics, spontaneous chiral symmetry breaking generates new phases of quark matter, and leads to significant changes od quark masses. The Nambu-Jona–Lasinio (NJL) model is a useful fermionic model which describes the spontaneous chiral symmetry breaking through the creation of a condensate. This model can be for instance used to determine various phases of Quantum Chromodynamics (QCD) in finite electromagnetic fields. This work consists of several parts. First, we describe the spontaneous chiral symmetry breaking in detail. Second, we extract the NJL model from the Lagrangian density of QCD. Third, we derive a covariant form of the partition function of a fermionic system....

Providing a Solving Method for Post-Earthquake Resource Allocation Model with Uncertainties

, M.Sc. Thesis Sharif University of Technology Jamshidi, Fatemeh (Author) ; Rafiee, Majid (Supervisor)

Abstract

Large amounts of relief resources such as water, tents, medical equipment and fuel after a major disaster need to reach the affected people. Satisfying the needs of victims is crucial to the success of crisis relief operations, as a lack of relief resources can lead to the suffering and loss of lives of victims. According to studies, large-scale catastrophes have occurred frequently in recent years. Therefore, it is necessary to pay more attention to the management of post-crisis resources. Since the distribution of emergency resources depends largely on the efficiency and effectiveness of logistics operations, the primary objectives include minimizing logistics time and cost, minimizing...

Simulation and Experimental Study of Permeability Reduction in Porous Media Due to Mud Filtrate Invasion Under Dynamic Conditions

, Ph.D. Dissertation Sharif University of Technology Movahedi, Hamed (Author) ; Jamshidi, Saeed (Supervisor)

Abstract

The reduction of the effective permeability of the reservoir rock in the production area due to various factors is called formation damage. Formation damage is always one of the topics discussed in petroleum engineering. Among the primary and important cases that lead to damage to the formation are the filtration of drilling mud into the production area and the deposition of colloidal particles inside the porous rock during the drilling operation. The length of the productive zone in contact with the drilling fluid usually reaches several hundred feet in Iranian formations. In this study, the aim is to more accurately estimate the amount of permeability reduction caused by the penetration of...