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Experimental and Numerical Investigation of Reactive Absorption in the presence of Nanofluid and Magnetic field
, M.Sc. Thesis Sharif University of Technology ; Molaei Dehkordi, Asghar (Supervisor)
Abstract
The importance of gases and liquids absorption in the liquid falling film is mostly due to the wide applications of liquid falling film reactors in the chemical industries. In such a reactor the mass and heat transfer occur simultaneously, but in most cases, the importance of mass transfer is predominant. Therefore, the study of heat transfer in this kind of reactor is neglected. In order to improve the efficiency of absorption, different methods have been employed by researchers. Owing to the rapid growth of nanotechnology, nanofluids have widely been used for increasing the absorption of solution, recently. Magnetic fluids due to their unique combination, among different kinds of...
Analysis and Comparison of the Role of SNr and vlPFC in Value Learning and Memory and Value Guided Saccade
, M.Sc. Thesis Sharif University of Technology ; Ghazizadeh, Ali (Supervisor)
Abstract
Learning the value of the objects in the living environment of animals has a great significance in guiding the behavior of animals. Therefore, understanding the mechanisms and structures involved in this phenomenon in the brain is one of the topics of interest in modern neuroscience. One of the most important structures known in the mammalian brain that plays an important role in learning the value of objects is the Basal ganglia. The value signal of objects has been observed in different areas of this structure. Another important area of the brain, whose role in learning the value of objects has recently been investigated, is the area of the Ventrolateral Prefrontal Cortex (vlPFC). On the...
A unified benchmark for security and reliability assessment of the integrated chemical plant, natural gas and power transmission networks
, Article Journal of Natural Gas Science and Engineering ; Volume 96 , 2021 ; 18755100 (ISSN) ; Bozorgmehry Boozarjomehry, R ; Babaei, F ; Pishvaie, M. R ; Sharif University of Technology
Elsevier B. V
2021
Abstract
This work presents a simulation framework to investigate the rigorous transient behavior of integrated systems comprising natural gas and power transmission networks, and a chemical plant whose feedstock is natural gas. This framework entails dynamic models for the gas transmission network and the SynGas plant, and a continuous-time AC-power flow formulation with dispatchable loads. It addresses the following key challenges: (i) analyzing energy and chemical system interdependencies, and their impacts on each other's supply reliability and security; (ii) providing an environment conducive to settling a critical question of how to prioritize the natural gas consumption as fuels of power...
Agent-Based Optimization of Integrated Energy and Product Networks
, Ph.D. Dissertation Sharif University of Technology ; Bozorgmehry Boozarjomehry, Ramin (Supervisor) ; Pishvaie, Mahmoud Reza (Supervisor)
Abstract
The industrial paradigm shift toward intelligent and sustainable management stimulates policymakers to leverage artificial intelligence for the decentralized planning of chemical industries with energy networks. By doing so, this work firstly presents a simulation framework to investigate the rigorous transient behavior of integrated systems comprising natural gas and power transmission networks, along with a chemical plant whose feedstock is natural gas. This framework entails dynamic models for the gas transmission network and the SynGas plant, and a continuous-time AC-power flow formulation with dispatchable loads. It addresses the following key challenges: (i) analyzing energy and...
Effect of Vertical Component of Earthquake on Cable-stayed Bridges
, M.Sc. Thesis Sharif University of Technology ; Maleki, Shervin (Supervisor)
Abstract
Cable stayed bridges have been used extensively in recent years for long span bridges up to 1000m. Although seismic behavior of these bridges has been researched in the last decade, however, the effect of vertical component of earthquake on cable-stayed bridges has not been studied before. In this thesis, the geometric nonlinear static analyses on dead loads followed by linear direct integration dynamic analyses have been used to study this effect. The results of analyses with three-component earthquakes are compared with two-component earthquakes. Fourteen models of cable-stayed bridges with different main span length, shape of pylons and the deck-pylon connection are employed. The errors...
An Investigation of Signal Processing Techniques for Monitoring of the Heart Abnormalities
, M.Sc. Thesis Sharif University of Technology ; Ghorshi, Alireza (Supervisor)
Abstract
In this thesis we have investigated and improved the signal processing techniques which are used for monitoring the heart abnormalities in terms of ECG (ElectroCardioGram) signals in order to detect heart attacks before they occur. De-noising ECG signals are one of the most important research topics in computer and electrical engineering fields. There are many different algorithms for de-noising signals in various domains. It usually is needed to propose a suitable algorithm for each specific system. In some cases instead of developing a new algorithm, we could modify the available ones for de-noising in our system. ECG signals are output from an electrocardiograph which measures electrical...
Tunable velocity-based deterministic lateral displacement for efficient separation of particles in various size ranges
, Article Physics of Fluids ; Volume 35, Issue 7 , 2023 ; 10706631 (ISSN) ; Dezhkam, R ; Shamloo, A ; Sharif University of Technology
American Institute of Physics Inc
2023
Abstract
Deterministic lateral displacement (DLD) is a promising method showing great potential in achieving high-resolution separation of suspended particles based on their size, through the use of micropillars arranged in a periodic manner. In the traditional approach to DLD, the migration mode of a particle with a specific size is determined by the critical diameter (Dc), which is predetermined by the device's geometry. In contrast to conventional DLD chips that alter the direction of the pillar array to create an angle with the fluid streamlines, this paper proposes a novel approach by changing the direction of the streamlines. The proposed method enables the fabrication of a tunable DLD chip...
CPM: A congestion control method for interplanetary network
, Article Canadian Conference on Electrical and Computer Engineering ; 2014 ; Mortazavi, M ; Ghorshi, S ; Sharif University of Technology
2014
Abstract
The vision of future space exploration includes missions to deep space that require communication among ground stations on ground and another planets such as mars, moons, satellites in different orbiters, asteroids, robotic spacecrafts, and specially for crewed vehicles for delivering information. These communications requires high bit rate for autonomous operations and also have several different limitations. These type of communications set as a network that is called Interplanetary Network (IPN). There are difference challenges in space communication that TCP and UDP are not able to address them such as Long propagation delay, asymmetric bandwidth, etc. In this work, a congestion method...
Interference alignment for two-user two-hop interference X-channel with delayed and no CSIT
, Article International Congress on Ultra Modern Telecommunications and Control Systems and Workshops, 6 October 2014 through 8 October 2014 ; Volume 2015-January, Issue January , 2015 , Pages 473-479 ; 21570221 (ISSN) ; Mirmohseni, M ; Akhaee, M. A ; Sharif University of Technology
IEEE Computer Society
2015
Abstract
Capacity approximation of multi-hop unicast and multi-hop multicast channels is one of unsolved problems in information theory. Recently some researches investigate Degrees of Freedom (DoF) characterization and Interference Alignment schemes for these channels. However most of them assumed perfect instantaneous Channel State Information (CSI) at the relays and the transmitters. Due to practical limitations, like the delay and the rate limitation in the feedback links and the fading channels, it is difficult to provide perfect instantaneous CSI at the transmitters and even the relays. Achievable DoF by the IA schemes collapses greatly with imperfect CSI. It has been shown that the delayed CSI...
Blind interference alignment for three-user multi-hop SISO interference channel
, Article International Congress on Ultra Modern Telecommunications and Control Systems and Workshops, 6 October 2014 through 8 October 2014 ; Volume 2015-January, Issue January , 2015 , Pages 462-467 ; 21570221 (ISSN) ; Mirmohseni, M ; Akhaee, M. A ; Sharif University of Technology
IEEE Computer Society
2015
Abstract
Interference Alignment (IA) is a rather new technique to achieve higher Degrees-of-Freedom (DoF) compared to traditional orthogonal naive methods, like, Time Division Multiple Access (TDMA). In many IA schemes, Instantaneous Channel State Information at Transmitter (CSIT) is mandatory. However, this requirement becomes an obstacle to implement those methods in practice. In some practical scenarios, it is not possible to provide instantaneous or even delayed CSIT. Recently, Blind Interference Alignment (BIA) has been introduced as a solution to align interference without CSIT. In spit of major advances in single-hop Interference Channels (ICs), few researches focused on multi-hop ICs. In this...
Inclusion Problem in Linear Viscoelastic Media
, M.Sc. Thesis Sharif University of Technology ; Mohammad Shodja, Hossein (Supervisor)
Abstract
In this study, using the correspondence principle and Laplace transform, the results obtained in the elastic medium for the Eshelby inclusion problem are expanded into the linear viscoelastic medium. The simplicity and breadth of application of the correspondence principle is so great that it enables one to obtain closed-form solutions in Laplace domain for problems that have closed form solutions in elastic media. However, in complex problems, the long formulas lead the user to apply numerical methods to perform inverse Laplace transform. First, by taking advantage of Green’s function the strain and stress fields are obtained in Laplace domain for the points lying inside and outside of an...
Developing an Efficient Framework for Involving Degradation Model of Lithium-ion Battery in Optimization Studies of a Residential Energy Hub
, M.Sc. Thesis Sharif University of Technology ; Moeini Aghtaie, Moein (Supervisor)
Abstract
Energy storage systems are expected to play an important role in future renewable-based power systems. Recently, lithium-ion batteries have been attracting considerable attention as alternative energy storage systems due to their advantages. In this study, viability of battery storage systems as large-scale energy storage systems is studied in the context of a residential energy hub. A stochastic optimization problem is proposed for energy management of the energy hub where wind generation and demand are considered uncertain. In order to account for the degradation costs of the battery storage system, a data-driven State-of-health prediction model is developed based on the relevance vector...
Manipulation of the electric field of electrospinning system to produce polyacrylonitrile nanofiber yarn
, Article Journal of the Textile Institute ; Volume 98, Issue 3 , 2007 , Pages 237-241 ; 00405000 (ISSN) ; Hosseini, Y ; Hosseini Ravandi , S. A ; Sharif University of Technology
2007
Abstract
Electrospinning is a process that produces nanofiber through the action of an external electric field imposed on a polymer solution or melt. This paper introduces a new system capable of producing continuous uniaxially aligned PAN nanofiber yarn by manipulating the electric field. The manipulation was carried out by employing a negative charged bar in the electric field of conventional electrospinning system, leading to the formation of an electrostatic multipolar field. As a result, the main stream was redirected towards a rotating take up unit, collecting the twisted yarn consisting of uniaxially aligned nanofibers. The yarns were then treated in boiling water under tension and their...
A data-driven state-of-health estimation model for lithium-ion batteries using referenced-based charging time
, Article IEEE Transactions on Power Delivery ; Volume 38, Issue 5 , 2023 , Pages 3406-3416 ; 08858977 (ISSN) ; Parvareh, A ; Moeini Aghtaie, M ; Dehghanian, P ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2023
Abstract
Accurate online state of health (SOH) estimation is crucial for the efficient and safe operation of lithium-ion battery packs in electric vehicles and grid-connected energy storage units. This paper proposes a novel data-driven SOH estimation model for lithium-ion batteries based on a new health indicator, namely referenced-based charging time. The proposed model utilizes the referenced-based charging time of partial charging cycles to predict the SOH using a machine learning approach. A deep feed-forward neural network, characterized via testing 90 different shallow and deep architectures, is implemented, trained, and tested on 17 batteries, which are cycled differently. The results show...
Effects of Spin- Orbit Coupling on the Phase Diagram of Doped Mott Insulator
, M.Sc. Thesis Sharif University of Technology ; Vaezi, Abolhassan (Supervisor) ; Ejtehadi, Mohammad Reza (Supervisor)
Abstract
In the past few years, topological insulators (TIs), topological superconductors and their experimental observation have been in the center of condensed maer physicists’ aention. Kane and Mele proposed the simplest and the first model exhibiting TI phase for non-interacting electrons on the two dimensional honeycomb laice. On the other hand, in the Hubbard model for nonzero doping and near the half filling, the high temperature superconductivity is predicted theoretically. In this thesis, we fist investigate the interacting topological insulators by adding the Hubbard interaction to the Kane-Mele model. en, in the strong correlation limit we find an effective spin model -the so called...
Clustering Wireless Camera Sensor Network Based on Overlapped Region Detection
, M.Sc. Thesis Sharif University of Technology ; Khansari, Mohammad (Supervisor) ; Akbari, Behzad (Co-Advisor)
Abstract
According to increase of multimedia applications such as video surveillance and environment monitoring in Wireless Multimedia Sensor Networks (WMSN), energy conservation and prolonging network lifetime become increasingly important. Therefore, energy conservation and maximization of system lifetime are commonly recognized as a key challenge in the design and implementation of WMSNs. In these networks, nodes sense the area with high degree of correlation due to the overlapping Field Of Views (FoVs) and causes wasting network energy. We present “overlapped region detection clustering” as a new clustering method to reduce redundant video streams and overcome waste of the energy. We apply scene...
Development of consistent fish-bone simplified model with energy-based approach for efficient seismic evaluation of irregular steel moment resisting frames
, Article Soil Dynamics and Earthquake Engineering ; Volume 161 , 2022 ; 02677261 (ISSN) ; Ahmadie Amiri, H ; Esmailpur Estekanchi, H ; Kheirkhah Gildeh, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
This study aims to develop the Consistent Fish-Bone (CFB) simplified model for efficient estimation of Engineering Demand Parameters (EDPs) in irregular steel Moment Resisting Frames (steel-MRFs). To achieve this goal, some modifications based on the energy consistent approach have been applied to the Improved Fish-Bone (IFB) simplified model previously presented for reinforced concrete MRFs. These modifications include: 1) adding truss elements to the IFB model to consider the effect of flexural deformations and determining their areas by balancing the overturning moment and the strain energy due to the axial deformation of columns in the original steel-MRF with the overturning moment and...
Reliability Analysis in Interplanetary Netwok (IPN)
, M.Sc. Thesis Sharif University of Technology ; Mortazavi, Mohammad (Supervisor) ; Ghorshi, Ali Reza (Supervisor)
Abstract
Developing of space technology requires a realization of deep space scientific missions such as Mars exploration. NASA enterprises have outlined scientific challenges for success and reliable transfer of data for new design and version of space network architecture.These communications requires high bit rate for autonomous operations and also have several different limitations. These type of communications set as a network that is called IPN. One of the important challenges in IPN is reliability. As regard there are difference challenge in space communication that TCP is not capable to address Long propagation delay, asymmetric bandwidth and etc. Therefore we require new protocols that will...
Synergy between hemagglutinin 2 (HA2) subunit of influenza fusogenic membrane glycoprotein and oncolytic Newcastle disease virus suppressed tumor growth and further enhanced by Immune checkpoint PD-1 blockade
, Article Cancer Cell International ; Volume 20, Issue 1 , August , 2020 ; Ebrahimzadeh, M. S ; Abdolalipour, E ; Yazdi, M ; Hosseini Ravandi, H ; Ghaemi, A ; Sharif University of Technology
BioMed Central Ltd
2020
Abstract
Background: Newcastle disease virus (NDV) has shown noticeable oncolytic properties, especially against cervical cancer. However, in order to improve the spread rate and oncotoxicity of the virus, employment of other therapeutic reagents would be helpful. It has been shown that some viral fusogenic membrane glycoproteins (FMGs) could facilitate viral propagation and increase the infection rate of tumor cells by oncolytic viruses. Additionally, immune checkpoint blockade has widely been investigated for its anti-tumor effects against several types of cancers. Here, we investigated for the first time whether the incorporation of influenza hemagglutinin-2 (HA2) FMG could improve the oncolytic...
Evaluation of cellular attachment and proliferation on different surface charged functional cellulose electrospun nanofibers
, Article Carbohydrate Polymers ; Volume 207 , 2019 , Pages 796-805 ; 01448617 (ISSN) ; Karimi, A ; Gandomi Ravandi, S ; Vossoughi, M ; Khafaji, M ; Joghataei, M. T ; Faghihi, F ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Fabrication and characterization of different surface charged cellulose electrospun scaffolds including cellulose acetate (CA), cellulose, carboxymethyl cellulose (CMC) and quaternary ammonium cationic cellulose (QACC) for biomedical applications have been reported in this research. Several instrumental techniques were employed to characterize the nanofibers. MTT assay and cell attachment studies were also carried out to determine the cytocompatibility, viability and proliferation of the scaffolds. Fabricated CA, cellulose, CMC and QACC nanofibers had 100–600 nm diameter, −9, −1.75, −12.8, + 22 mV surface potential, 2.5, 4.2, 7.2, 7 MPa tensile strength, 122, 320, 515, 482 MPa Young modules,...