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khorashadizadeh--amir-ehsan
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Pruning Machine Learning Models by Sparse Representation
,
M.Sc. Thesis
Sharif University of Technology
;
Babaiezadeh, Massoud
(Supervisor)
Abstract
In recent years, Machine Learning models have been developed in Signal Processing, Computer Vision and Neuroscience areas. There are two categories of Machine Learning models which are supervised and unsupervised learning models. Regression and classification problems are two popular problems examples of supervised learning models. From unsupervised learning problems, we can mention the clustering problem. Support Vector Regression (SVR), Decision Tree Regression and Bagging Ensemble Regression models are some important models of the regression problem. For classification problems, we can also mention to Support Vector Classification, Decision Tree Classification, and Bagging Ensemble...
Probabilistic optimal power dispatch in multi-carrier networked microgrids under uncertainties
, Article Energies ; Volume 10, Issue 11 , 2017 ; 19961073 (ISSN) ; Jadid, S ; Ehsan, M ; Sharif University of Technology
2017
Abstract
A microgrid (MG) is a small-scale version of the power system which makes possible the integration of renewable resources as well as achieving maximum demand side management (DSM) utilization. The future power system will be faced with severe uncertainties owing to penetration of renewable resources. Consequently, the uncertainty assessment of system performance is essential. The conventional energy scheduling in an MG may not be suitable for active distribution networks. Hence, this study focuses on the probabilistic analysis of optimal power dispatch considering economic aspects in a multi-carrier networked microgrid. The aim is to study the impact of uncertain behavior of loads, renewable...
Optimal planning of a multi-carrier microgrid (MCMG) considering demand-side management
, Article International Journal of Renewable Energy Research ; Volume 8, Issue 1 , 2018 , Pages 238-249 ; 13090127 (ISSN) ; Jadid, S ; Ehsan, M ; Sharif University of Technology
International Journal of Renewable Energy Research
2018
Abstract
The multi-carrier microgrid (MCMG) is a restricted district comprising convertors and energy storage systems (ESSs) that are used to fulfill various energy demands. The structure and optimal operation of these MCMGs with regard to fulfilling multi-carrier demands are presented in relation to their rapid spread. In this paper, a two-stage optimum planning and design method for an MCMG is presented in the planning horizon. The investment and operation (fuel and maintenance) costs are considered concurrently to find the optimal type and size of components over the planning horizon. At the first stage, the genetic algorithm (GA) is applied to determine the optimal type and size of components,...
Operation of multi-carrier microgrid (MCMG) considering demand response
, Article Journal of Operation and Automation in Power Engineering ; Volume 7, Issue 1 , 2019 , Pages 119-128 ; 23224576 (ISSN) ; Jadid, S ; Ehsan, M ; Sharif University of Technology
University of Mohaghegh Ardabili, Faculty of Electrical Engineering
2019
Abstract
In this paper, the operation of a future distribution network is discussed under the assumption of a multi-carrier microgrid (MCMG) concept. The new model considers a modern energy management technique in electricity and natural gas networks based on a novel demand side management (DSM) which the energy tariff for responsive loads are correlated to the energy input of the network and changes instantly. The economic operation of MCMG is formulated as an optimization problem. In conventional studies, energy consumption is optimized from the perspective of each infrastructure user without considering the interactions. Here, the interaction of energy system infrastructures is considered in the...
Operation of networked multi-carrier microgrid considering demand response
, Article COMPEL - The International Journal for Computation and Mathematics in Electrical and Electronic Engineering ; Volume 38, Issue 2 , 2019 , Pages 724-744 ; 03321649 (ISSN) ; Jadid, S ; Ehsan, M ; Sharif University of Technology
Emerald Group Publishing Ltd
2019
Abstract
Purpose: Microgrids are inclined to use renewable energy resources within the availability limits. In conventional studies, energy interchange among microgrids was not considered because of one-directional power flows. Hence, this paper aims to study the optimal day-ahead energy scheduling of a centralized networked multi-carrier microgrid (NMCMG). The energy scheduling faces new challenges by inclusion of responsive loads, integration of renewable sources (wind and solar) and interaction of multi-carrier microgrids (MCMGs). Design/methodology/approach: The optimization model is formulated as a mixed integer nonlinear programing and is solved using GAMS software. Numerical simulations are...
Design and Implementation of an Access Control Mechanism Based on SBAC
, M.Sc. Thesis Sharif University of Technology ; Jalili, Rasoul (Supervisor)
Abstract
In order to control accesses in semantic environments, a semantic-based access control and policy specification language should be choosen. Upon to them, some security mechanisms should be designed and implemented. Several access control models and policy specification languages have been arisen, but seldom have focused on designing mechanisms to satisfy their models in any environment. In this thesis, we focus on implementation aspects of access control in semantic environments. We chose semantic web as our studying environment and an extension of the SBAC model named MA(DL)2 as our access control model. To control accesses in the selected environment, we divide semantic web into some...
Dispositional Essentialism and its Contradiction with Humean Metaphysics
, M.Sc. Thesis Sharif University of Technology ; Karbasizade, Amir Ehsan (Supervisor)
Abstract
In recent decades one neo-Aristotelian school in metaphysics has appeared that with reconstruction on concept of "potency" or "power" try to explain metaphysical problems as: properties ,causation, laws of nature ,modalities and … .this school contradict all classical views in analytic metaphysics ,because they have commitment to Humean metaphysics that all metaphysical categories supervene on distinct particular facts in nature. Dispositional essentialism is one neo-Aristotelian theory saying that some natural properties have dispositional essence. In strong view of this theory, identity of properties supervenes on the structure of a network of properties and therefore properties are...
Hume on Causation
, M.Sc. Thesis Sharif University of Technology ; Karbasizadeh, Amir Ehsan (Supervisor)
Abstract
The Concept of causation plays a major role in Hume’s philosophy and as yet has been debated between philosophers. This Thesis aims to Consider the main part of Hume’s view about Causation, but it also Ventutes into more recent approaches in this subject. In first chapter, we attend to Consider The project of Hume named "Seience of man" and The associative mechanism of causation is expressed. In Second chapter, We turn to three famous interpretations of Hume’s view and the meaning of two definitions of Causation is discussed. In third chapter, we try to analyse the real nature of necessary Connection. According to fourth chapter, we again attend to three interpretations and recognize the...
Identical Particles
, M.Sc. Thesis Sharif University of Technology ; Karbasizade, Amir Ehsan (Supervisor)
Abstract
Modern physics and the standard metaphysical point of view, together, result a contradiction which we will explore its roots in this thesis. Be- sides, focusing on various identifications of individuality and the prin- ciple of identity of indiscernibles will made us to choose between to metaphysical and equal pockets, Particles as individuals and particles as non-individuals.Physics alone could not help to choose between these too pockets. Therefore, we will face a metaphysical under-etermination which we have to break in order to save our realistic ontological com-mitments. By a breif study among the possible ways for breaking that underdetermination, structural realism will be the most...
Laws and Lawmakers
, M.Sc. Thesis Sharif University of Technology ; Karbasi Zadeh, Amir Ehsan (Supervisor)
Abstract
In Laws and Lawmakers: Science Metaphysics and the laws of nature, Mark Lang has presented an engagingly written, tightly argued, and novel philosophical account of the laws of nature. One of the intuitions behind the notion of a law of nature is, roughly, that of the many regularities we observe in the world there are some which appear to be due to mere happen-stance(“accidental” regularities, in the philosopher’s jargon)while others, which we call “laws,” seem to be possessed of a degree of necessity. although many philosophers, and certainly most scientists, will readily agree that there is a difference between logical, law-like, and accidental regularities, spelling out the nature of...
Predicting Groundwater Level Changes in the Varamin Plain Using Machine Learning Models and Optimization Algorithms
, M.Sc. Thesis Sharif University of Technology ; Khorashadizadeh, Farkhondeh (Supervisor)
Abstract
Predicting groundwater level fluctuations is essential for effective water resource management and environmental preservation. This study examines and compares two modeling techniques, namely Wavelet Neural Networks (WNN) and Artificial Neural Networks (ANN), for predicting fluctuations in the aquifer levels in the Varamin plain. Traditional hydrological models often struggle to detect nonlinear relationships present in hydrological data, which may lead to inconsistencies in predictions. The research focuses on groundwater level fluctuations in the Varamin plain over a 30-year period, from October 1989 to September 2018. Statistical methods such as mean, median, and variance calculations are...
Application of Ferrate for Enhancing Refinery Wastewater Treatment Quality toward Recycling and Reuse in Cooling Towers (Case Study: Tehran Oil Refinery)
, M.Sc. Thesis Sharif University of Technology ; Khorashadizadeh, Farkhondeh (Supervisor)
Abstract
This study evaluated the feasibility of upgrading the treated effluent from the Tehran Oil Refinery wastewater treatment plant for reuse as cooling tower makeup water. Due to the high concentrations of dissolved solids, phosphate, silica, and COD, the direct use of this effluent causes scaling, corrosion, and biofouling in cooling systems. To address these issues, a hybrid advanced treatment train comprising pre-oxidation and coagulation using ferrate (Fe(VI)), followed by mixed-bed ion exchange (MB400) and a final remineralization stage, was employed. The goal was to simultaneously reduce organic, colloidal, and ionic loads with minimal energy and chemical consumption and to produce a...
Sober On Intelligent Design
, M.Sc. Thesis Sharif University of Technology ; Miandari, Hassan (Supervisor) ; Karbasizadeh, Amir Ehsan (Supervisor)
Abstract
Intelligent design theory is based on this idea that Darwinian theory of evolution can not explain Irreducibly complexities in organisms. Intelligent design theory in explaining these complexities conclude the existence of an intelligent designer. It is claimed that by remaining officially agnostic about the nature of the designer, intelligent design theory can be offered as a scientific claim, rather than a religious one, which could make it a viable alternative to Darwinism. In this thesis we study sober's point of view on intelligent design. Sober believes that, initially, we shoud present the strongest formulation of intelligent design theory and then evaluating whether this theory is a...
Life Cycle Environmental Assessment of Polyethylene Process/Multiobjective Optimization
, M.Sc. Thesis Sharif University of Technology ; Farhadi, Fatollah (Supervisor) ; Vafa, Ehsan (Supervisor)
Abstract
The environmental impacts of chemical processes significantly affect the design of these processes and emphasize issues such as changing the reaction path, separation methods, thermal integration, and finally multi-objective optimization. Therefore, it is necessary to investigate the influence of environmental indicators in the design of chemical processes. The background system in this assessment includes two process units, olefin and polyolefin. Environmental impacts assessment has been carried out using the ReCiPe endpoint method (an efficient method for life cycle impact assessment that will be described in chapter 2) and these impacts have been determined in the form of damage to human...
Dynamic Modeling of a Bubble Column Bioreactor Using Hybrid Neural Networks
, M.Sc. Thesis Sharif University of Technology ; Pishvaie, Mahmoud Reza (Supervisor) ; Vafa, Ehsan (Supervisor)
Abstract
With the daily increasing demand for energy, we are facing many crises, such as environmental pollution and global warming, etc. Geopolitical issues can also lead to problems for some countries in reaching the energy demand considered in their development plan of them. For this purpose, a part of the global research is focused on removing these obstacles. One of the methods that can be used to produce cleaner fuel, or more precisely "biofuel", is the gaseous fermentation of synthesis gas by microorganisms and algae. A rod-shaped, anaerobic microorganism called Clostridium ljungdahlii uses synthesis gas for its reproduction. In other words, this bacterium can ferment carbon monoxide, carbon...
Integration of Artificial Intelligence, Remote Sensing, and Field Data for Simulation of Chlorophyll-a Concentration in Gorgan Bay
, M.Sc. Thesis Sharif University of Technology ; Khorashadizadeh, Farkhondeh (Supervisor)
Abstract
Chlorophyll-a, as an important component in evaluating water resources, has a significant impact on the status of water resources. This component is dependent on various quality parameters, such as phosphorus concentration, nitrogen concentration, turbidity, suspended solid concentration, temperature, pH, and dissolved oxygen concentration in water. To evaluate the quality status of surface water, it is necessary to estimate the exact concentration of chlorophyll-a in different temporal and spatial ranges. The objective of this study is to simulate and predict the concentration of chlorophyll-a in different temporal and spatial ranges using a combined application of machine learning models,...
New approach for fatigue life prediction of composite plates using micromechanical bridging model
, Article Journal of Composite Materials ; Volume 49, Issue 3 , February , 2015 , Pages 309-319 ; 00219983 (ISSN) ; Farsadi, M ; Koochi, A ; Khorashadizadeh, S. N ; Sharif University of Technology
SAGE Publications Ltd
2015
Abstract
The use of micromechanical models to study composite material's behavior leads to save time and cost. In this paper, bridging micromechanical models have been used in order to observe the behavior of unidirectional laminate composite under fatigue loading. In order to study the fatigue behavior, stiffness degradation has been studied as well as the strength degradation and a driftnet model has been proposed for each of them. The strength degradation has only been studied for the unidirectional fiber, while the stiffness degradation has been studied for the fibers with different fiber angle. The results are compared with macro-mechanical models and other methods in literature
Deep variational inverse scattering : (invited paper)
, Article 17th European Conference on Antennas and Propagation, EuCAP 2023 ; 2023 ; 978-883129907-7 (ISBN) ; Aghababaei, A ; Vlasic, T ; Nguyen, H ; Dokmanic, I ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2023
Abstract
Inverse medium scattering solvers generally reconstruct a single solution without an associated measure of uncertainty. This is true both for the classical iterative solvers and for the emerging deep-learning methods. But ill-posedness and noise can make this single estimate inaccurate or misleading. While deep networks such as conditional normalizing flows can be used to sample posteriors in inverse problems, they often yield low-quality samples and uncertainty estimates. In this paper, we propose U-Flow, a Bayesian U-Net based on conditional normalizing flows, which generates high-quality posterior samples and estimates physically-meaningful uncertainty. We show that the proposed model...
Structural stability and sustained release of protein from a multilayer nanofiber/nanoparticle composite
, Article International Journal of Biological Macromolecules ; Volume 75 , April , 2015 , Pages 248-257 ; 01418130 (ISSN) ; Mashayekhan, S ; Shabani, I ; Khorashadizadeh, M ; Fallah, A ; Soleimani, M ; Sharif University of Technology
Elsevier
2015
Abstract
The cellular microenvironment can be engineered through the utilization of various nano-patterns and matrix-loaded bioactive molecules. In this study, a multilayer system of electrospun scaffold containing chitosan nanoparticles was introduced to overcome the common problems of instability and burst release of proteins from nanofibrous scaffolds. Bovine serum albumin (BSA)-loaded chitosan nanoparticles was fabricated based on ionic gelation interaction between chitosan and sodium tripolyphosphate. Suspension electrospinning was employed to fabricate poly-e{open}-caprolacton (PCL) containing protein-loaded chitosan nanoparticles with a core-shell structure. To obtain the desired scaffold...