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An Investigation of Leggett’s Inequality
, M.Sc. Thesis Sharif University of Technology ; Shafiee, Afshin (Supervisor)
Abstract
Quantum correlations are among most intriguing problems in physics. Bell’s inequality which was proved in 1964 provides with us the possibility of comparing the predictions of quantum theory with what an underlying local realistic theory may reproduce for some given observables in correlated states. The violation of Bell’s inequality in practice prohibits the existance of such underlying theories. Yet, it is not clear which of the assumption, i.e., locality or reality is responsible for explaining the experimentally verified violations. In 2003, a Nobel prizewinner A. J. Leggett proved a new inequality in which the locality assumption was not crucial. Here, we explore different aspects of...
A Process Mining Approach to Analyze Customer Journeys to Improve Customer Experience
, M.Sc. Thesis Sharif University of Technology ; Hassannayebi, Erfan (Supervisor)
Abstract
With the growth of the number of online service providers and the need to innovate in these services, in this study, the processes and the journeys taken by visitors of a website that provides employment services and employment insurance has been analyzed. In this research, process mining techniques and predictive process monitoring were implemented. With the use of a supervised and unsupervised learning algorithm, it attempted to identify the customer journeys' output and the existing patterns that lead to the complaint. In the first step, the website event log is extracted. Afterward, by using frequency-based encoding methods, the journeys traveled by users were clustered based on the...
Predictive Business Process Monitoring Using Machine Learning Algorithms
, M.Sc. Thesis Sharif University of Technology ; Hassannayebi, Erfan (Supervisor)
Abstract
In order to survive in today's business world, which is changing at a very fast pace, organizations can detect deviations even before they occur, quickly and with a high percentage of confidence, by analyzing their processes, in order to prevent disruptions in the processes. by monitoring the information systems that automatically execute business processes, it is possible to ensure the correct implementation of the existing processes. For this purpose, various techniques for monitoring business processes have been presented so that managers have a comprehensive and real view of how implement processes and be able to identify possible deviations in the future and try to fix them because the...
Data-Driven Prediction for Monitoring Business Process Pperformances Based on Classification Algorithms
, M.Sc. Thesis Sharif University of Technology ; Hassannayebi, Erfan (Supervisor)
Abstract
In recent years, several studies have been conducted in the field of data mining techniques in the field of process mining with the aim of improving the performance of organizations. Predictive process monitoring is a data-driven approach that helps business managers to improve the status and conditions of their organization. In this approach, the event log, which includes a set of completed examples of a process, is received as input, and machine learning methods are used to predict the outcome and results of the organization's processes before the process is completed. This prediction can include the prediction of the final result, the next event, the time remaining until the completion of...
Evaluation of upper Limb Kinematic Synergies in Parkinson's Patients in Medication States and before and after Rehabilitation
, M.Sc. Thesis Sharif University of Technology ; Behzadipour, Saeed (Supervisor)
Abstract
Parkinson's disease is a destructive and long-term disease of the central nervous system. This disease especially affects the motor system. Parkinson's patients can be studied under dopaminergic and non-dopaminergic conditions. The non-dopaminergic state means not taking the drug, for at least 12 hours, and the dopaminergic state, from one hour to less than 12 hours after taking the usual dose of the dopaminergic drug. The aim of this study is to examine and compare the statistics and characteristics of Parkinson's patients in dopaminergic and non-dopaminergic states, focusing on reaching and tracking activities. It also aims to analyze the differences before and after rehabilitation in...
Operations Optimization in Supply Chain Systems using Simulation and Reinforcement Learning
, M.Sc. Thesis Sharif University of Technology ; Hassan Nayebi, Erfan (Supervisor)
Abstract
The inventory costs constitute a significant portion of the supply chain costs. Therefore, choosing an optimal inventory policy for orders is of great importance. The aim of this research is to find the optimal inventory policy for a distribution center in a three-tier supply chain consisting of a manufacturer, a distribution center, and a retailer. This research simulates a supply chain in agent-based framework and optimizes it using reinforcement learning. The optimization KPI in this research is the mean daily cost of the supply chain. Finally, the result obtained from reinforcement learning is compared with the optimized result of AnyLogic and the mean daily cost in the model optimized...
A System Dynamic Simulation Approach to Investigate Economic And Environment Factors Based on VUCA framework: A Case Study in Petrochemical Industry
, M.Sc. Thesis Sharif University of Technology ; Hassannayebi, Erfan (Supervisor)
Abstract
To maintain adaptability, businesses should anticipate changes in their environment. The commonly employed forecasting method within corporate circles is the bottom-up approach, which relies on historical data for projecting future trends. However, research suggests that this approach often falls short of accurately reflecting real-world events. This has led to the adoption of dynamic systems modeling, a technique grounded in the assumption of stable conditions. This method effectively replicates the system's current state, thereby assisting in predicting future behaviors over a longer timeframe. The dynamic systems modeling approach was employed in this study, underscoring the imperative...
Discovering and Improving the Processes of an Iranian Psychiatric Hospital Using Process Mining
, M.Sc. Thesis Sharif University of Technology ; Hassan Nayebi, Erfan (Supervisor)
Abstract
Providing quality hospital services depends on the efficient and correct implementation of processes. Therapeutic care processes are a set of activities that are carried out with the aim of diagnosing, treating and preventing any disease in order to improve and promote the patient's health. The purpose of this study is to use process mining techniques to discover and improve healthcare processes. The case study of this research is a psychiatric hospital in Shiraz. The approach implemented in this research consists of three main stages including data pre-processing, model discovery phase, and analysis phase. Three algorithms including Heuristic Miner, Inductive Miner, and ILP Miner were used...
Application of Hybrid Metaheuristics in Solving Magic Type Labeling of Graphs
, M.Sc. Thesis Sharif University of Technology ; Eshghi, Koorosh (Supervisor)
Abstract
Graph Labeling is one of the most active initiatives in graph theory which was introduced in the early 1960’s. One of the most prominent kind of labeling in literature is magic-type labeling inspired by defining magic numbers and magic squares. It also encompasses various types. Total edge magic labeling of Graph G, is a bijection f from V(G)∪E(G) on the set of {1,2,…,|V(G) |+|E(G) |}, on this condition that the summation of each edge label and its vertices’ labels is constant for all edges. Since introducing total edge magic labeling, numerous researches is done that mostly are dedicated to prove mathematical theorems and depicting a whether a distinct graph is magic or not. Therefore, it...
Immobilization of Laccase onto Graphene Oxide-based Nano-Composites for Decolorization of Colored Wastewaters
, Ph.D. Dissertation Sharif University of Technology ; Borghei, Mehdi (Supervisor) ; Mahmoodi, Neyazmohammad (Supervisor)
Abstract
Using free laccase, enzymatic decolorization of two azo dyes were optimized. The optimum conditions with the aim of maximizing the decolorization of AB92 dye (92.30%) were: dye concentration = 11.85 mg L-1, pH = 5.1, and enzyme concentration = 98.37 mg L-1. While, these conditions to achieve the maximum decolorization yield of DR23 (95.60%) were: dye concentration = 17.68 mg L-1, pH 3.7 and enzyme concentration =97.89 mg L-1.In the second part, the laccase enzyme was covalently immobilized onto GO nanosheets. At the concentration of graphene oxide and laccase enzyme equal to 1 mg mL-1 and 0.9 mg mL-1, respectively, the enzyme loading was 156.5 mg g-1 and the immobilization efficiency was...
Covalently immobilized laccase onto graphene oxide nanosheets: Preparation, characterization, and biodegradation of azo dyes in colored wastewater
, Article Journal of Molecular Liquids ; Volume 276 , 2019 , Pages 153-162 ; 01677322 (ISSN) ; Borghei, S. M ; Mahmoodi, N. M ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this study, graphene oxide (GO) was synthesized via modified Hummer's method and exploited as an ideal enzyme immobilization support due to its exclusive chemical and structural features. Then, laccase from genetically modified Aspergillus was covalently immobilized onto GO (nanobiocatalyst). Enzymatic characterization of the nanobiocatalyst exhibited promising results: laccase loading of 156.5 mg g−1 and immobilization yield of 64.6% at laccase concentration of 0.9 mg/ mL. Further employment of various structural characterization techniques including Fourier Transform Infrared Spectroscopy (FTIR), X-ray Powder Diffraction (XRD), Scanning Electron Microscopy (SEM), Thermo-Gravimetric...
Superparamagnetic enzyme-graphene oxide magnetic nanocomposite as an environmentally friendly biocatalyst: Synthesis and biodegradation of dye using response surface methodology
, Article Microchemical Journal ; Volume 145 , 2019 , Pages 547-558 ; 0026265X (ISSN) ; Borghei, S. M ; Mahmoodi, N. M ; Sharif University of Technology
Elsevier Inc
2019
Abstract
The unique properties of graphene oxide (GO) nanosheets were integrated with the superparamagnetic characteristics of the CuFe2O4 nanoparticles to synthesize the magnetic graphene oxide (MGO), which was chemically modified with 3-amino propyl trimethoxy silane (APTMS) to functionalize the amine group on MGO (MGO-NH2). Afterward, MGO-NH2 was activated with glutaraldehyde (GLU) as a crosslinking agent to synthesize the functionalized MGO (fMGO) and its capability toward covalent Laccase immobilization was investigated. The comprehensive structural analysis using various characterization techniques, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), vibrating...
Application of face-centered central composite design (FCCCD) in optimization of enzymatic decolorization of two azo dyes: A modeling vs. empirical comparison
, Article Progress in Color, Colorants and Coatings ; Volume 12, Issue 3 , 2019 , Pages 179-190 ; 20082134 (ISSN) ; Borghei, S. M ; Mahmoodi, N. M ; Sharif University of Technology
Institute for Color Science and Technology
2019
Abstract
Biological treatment, especially enzymatic methods, can be employed for effective and environmental- friendly treatment of dye effluents. Laccase, belonging to the blue multi-copper oxidases category, can oxidize a wide variety of substrates, especially synthetic dyes. In this study, laccase was used to biodegrade two azo dyes, i.e., Direct Red 23 and Acid Blue 92. Before conducting the experiments, the laccase used in this study was enzymatically characterized. Face-centered central composite design (FCCCD) was used to optimize the main parameters of the decolorization process. The optimum conditions to maximize the bio-decolorization process of AB92 were X1=11.85 mg L-1, X2=5.10, and...
The investigation of natural super-cavitation flow behind three-dimensional cavitators: Full cavitation model
, Article Applied Mathematical Modelling ; Volume 45 , 2016 , Pages 165-178 ; 0307904X (ISSN) ; Kadivar, Erfan ; Javadi, K ; Javadpour, S. M ; Sharif University of Technology
Elsevier Inc
2016
Abstract
In this study, natural super-cavitating flow around three different conical cavitators with wedge angles of 30°, 45° and 60° is investigated. We apply the k−ϵ turbulence model and the volume of fluid (VOF) technique to numerically study the three-dimensional cavitating flow around the cavitators. The turbulence approach is coupled with a mass transfer model which is implemented into the finite-volume package. Simulations are performed for different cavitation numbers. Finally, the effects of some important parameters such as the cavitation index, inlet velocity, Froude number and wedge angle of cavitators on the geometrical characteristics of the super-cavities are discussed. Our numerical...
Improve Performance of Process Mining Algorithms in Low-Level Event Log with Machine Learning Methods
, M.Sc. Thesis Sharif University of Technology ; Hassan Nayebi, Erfan (Supervisor)
Abstract
This thesis abstract addresses the use of process mining techniques when event data is stored at varying levels of granularity. While most techniques assume that events have the same level of granularity, real data is often stored differently. Pre-processing techniques allow for appropriate summarization of the data, which simplifies the output while retaining important process details. The goal is to ensure an interpretable output for stakeholders and different business teams without losing critical process points. However, adding new data as a feature to the dataset can be expensive, and at times, infeasible. Therefore, existing data is the only solution. To overcome this challenge, this...
Optimal Combination of Aerodynamic and Reaction Jet Control in a Vertical Launch Vehicle
, M.Sc. Thesis Sharif University of Technology ; Nobahari, Hadi (Supervisor) ; Kashefi, Saeid (Co-Advisor)
Abstract
In this research, the design of control system has been studied for a special flying vehicle at whole of flight time. This flying vehicle is vertically launched and few time after launch its attitude changes to the desired attitude by a reaction jet control system, then the acceleration commands are tracked when the aerodynamic is activated. Design process includes attitude control system design in launch phase and aerodynamic control system design. Because of the existence of nonlinear and multi-variable dynamics in the flying vehicle and the presence of uncertainty and disturbance, combination of nonlinear, robust and adaptive methods are used in controller design process. Design of...
A Low Altitude Optimal-fuzzy Guidance Algorithm for a Vertically Launched Flying Vehicle
, M.Sc. Thesis Sharif University of Technology ; Nobahari, Hadi (Supervisor) ; Kashefi, Saeed (Co-Advisor)
Abstract
An optimal-fuzzy low altitude two phase CLOS guidance algorithm for a vertically launched flying vehicle is presented. In addition, the required relations for determining the proper rotation angle of interceptor in the launch phase are derived. The guidance algorithm is designed for a three point guidance system and utilizes fuzzy sliding mode control as a regulator to compensate the guidance loop errors. Furthermore, for the purpose of trajectory shaping, a fuzzy system was employed to calculate the augmented elevation angle. Finally, a multi-objective optimization algorithm is used to determine 20 unknown parameters of the guidance law and 11 parameters of trajectory shaping system....
Optimization and Offering a kinetic Model for Enzymatic Hydrolysis of Cellulosic Materials in a Membrane Bio-reactor
, M.Sc. Thesis Sharif University of Technology ; Soltanieh, Mohammad (Supervisor) ; Shaygan Salek, Jalaloddin (Co-Advisor)
Abstract
Regarding decreasing resources of fossil fuels and their increasing costs in addition to their environmental pollutions, today, producing bio fuels from wastes such as lignocellulosic materials is of great interest. A fundamental stage in conversion of lignocellulosic materials into bio fuels, such as bio ethanol, is the enzymatic hydrolysis of these materials to produce reducing sugars. Researches have shown high costs of this stage. Optimization of enzymatic hydrolysisconditions is a major step in economization of this process.In this work corn hull is used to produce glucose. Corn hull is a kind of lignocellulosic material that due to high carbohydrate content is used as substrate. Our...
SYNCOP: An evolutionary multi-objective placement of SDN controllers for optimizing cost and network performance in WSNs
, Article Computer Networks ; Volume 185 , 2021 ; 13891286 (ISSN) ; Rasouli, N ; Kashefi, A. H ; Rezabeyk, E ; Faragardi, H. R ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Due to the highly dynamic nature of Wireless Sensor Networks (WSN), Software-Defined Network (SDN) is a promising technology to ease network management by providing a logically centralized control plane. It is a common approach to employ multiple SDN controllers to form a physically distributed SDN to achieve better fault tolerance, boost scalability, and enhance performance. Despite physical distribution, since the notion behind SDN is to logically centralize network management, it is essential to provide a consistent view of the network's state for all controllers. Deploying multiple controllers result in higher synchronization and deployment cost. Since network performance and...
Estimating Evaporation from Non-Agricultural Areas (Bare Soil and Range Land) in the Lake Urmia Basin
,
M.Sc. Thesis
Sharif University of Technology
;
Tajrishi, Masood
(Supervisor)
;
Jalilvand, Ehsan
(Co-Supervisor)
;
Haghighi, Erfan
(Co-Supervisor)
Abstract
Evaporation is one of the main parameters of the mass transfer from earth to the atmosphere, which annually transfers more than 65 billion cubic meters of water. Worldwide, evaporation consumes 25% of the energy input and plays a key role in restoring 60% of the precipitation to the atmosphere. Small changes in the water budget and evapotranspiration (ET) in arid and semi-arid areas can cause a large change in ecosystem health. Lake Urmia Basin has been taken into huge consideration due to steepest decline in lake level in the last three decades. Estimating evapotranspiration of this basin is important for the study of agricultural water consumption, hydrological modeling, water resources...