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Treatment of Triclosan Through Enhanced Microbial Biodegradation
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor) ; Ghobadi Nejad, Zahra (Supervisor)
Abstract
Triclosan is widely used as an antibacterial agent in personal health care products, especially in recent years with the spread of the Coronavirus. This substance is one of the emerging contaminants, and due to its stable and toxic nature, this material cannot be destroyed in the process of biological wastewater treatment. In this research, a new bacterial strain was isolated and purified from industrial wastewater for the biological removal of triclosan. Based on 16S rRNA sequencing, it was found that the isolated strain belongs to the Enterobacter cloacae family and can grow in high concentrations of triclosan. It was observed that naphthalene dioxygenase and laccase enzymes are active...
Comparison models evaluating countermeasures at Highway-Railway Grade Crossings
, Article ICTIS 2013: Improving Multimodal Transportation Systems - Information, Safety, and Integration - Proceedings of the 2nd International Conference on Transportation Information and Safety ; 2013 , Pages 1934-1945 ; 9780784413036 (ISBN) ; Bagheri, M ; Sharif University of Technology
2013
Abstract
This paper reviews the literature concerning the effectiveness of countermeasures at Highway-Railway Grade Crossings (HRGC). HRGC are considered as the hotspots in railway transportation systems. So far, there has been significant discussion about different types of countermeasure to mitigate the risk of accidents at HRGC. Different approaches have been developed about the effectiveness of the countermeasures including the Before-After and Cross-Sectional. This paper compares all different studies to evaluate the effectiveness of countermeasure in reduction of accident frequency and severity
Topics in Measurability and Integrability in Constructive Analysis
, Ph.D. Dissertation Sharif University of Technology ; Ardeshir, Mohammad (Supervisor)
Abstract
In this thesis, we investigate constructive measure theory in two schools of constructivism; intuitionistic mathematics and Bishop’s constructive mathematics.In this regard, first, we examine some classical propositions on measurability in both schools. Then we give a comparison between measurability in the two schools
An Efficient Network for Real-Time Semantic Segmentation
, M.Sc. Thesis Sharif University of Technology ; Kasaei, Shohreh (Supervisor)
Abstract
In real-time semantic segmentation, images are divided into predefined semantic regions at a speed exceeding 30 frames per second, and each point of the image is labeled with a category. The output of this fundamental task is to produce a representation that is comprehensible to computers for further processing in applications such as autonomous vehicles, robotics, and augmented reality. This task pursues two conflicting goals: improving the accuracy of segmentation and increasing its speed. Previous research has enhanced segmentation speed using lightweight and multi-branch structures and improved accuracy using attention mechanisms. Depth map alongside color image can lead to better...
Time-Cost efficient scheduling algorithms for executing workflow in infrastructure as a service clouds
, Article Wireless Personal Communications ; Volume 103, Issue 3 , 2018 , Pages 2035-2070 ; 09296212 (ISSN) ; Movaghar, A ; Mohsenzadeh, M ; Sharif University of Technology
Springer New York LLC
2018
Abstract
Cloud Computing enables delivery of IT resources over the Internet and follows the pay-as-you-go billing model. The cloud infrastructures can be used as an appropriate environment for executing of workflow applications. To execute workflow applications in this environment, it is necessary to develop the workflow scheduling algorithms that consider different QoS parameters such as execution time and cost. Therefore, in this paper we focus on two criteria: total completion time (makespan) and execution cost of workflow, and propose two heuristic algorithms: MTDC (Minimum Time and Decreased Cost) which aims to create a schedule that minimizes the makespan and decreases execution cost, and CTDC...
A budget constrained scheduling algorithm for executing workflow application in infrastructure as a service clouds
, Article Peer-to-Peer Networking and Applications ; 2018 , Pages 1-28 ; 19366442 (ISSN) ; Movaghar, A ; Mohsenzadeh, M ; Sharif University of Technology
Springer New York LLC
2018
Abstract
Cloud computing technology, which is a new model of service provisioning in distributed systems, has been raised as a way to execute workflow applications. To profit from this technology for executing workflow applications, it is necessary to develop workflow scheduling algorithms that consider different QoS parameters such as execution time and cost. Therefore, in this paper, we focus on two criteria: makespan (completion time) and execution cost of workflow application and propose a scheduling algorithm named CB-DT (Constrained Budget-Decreased Time) which aims to create a schedule that decreases the makespan while satisfying the budget constraint of the workflow application. In the...
A budget constrained scheduling algorithm for executing workflow application in infrastructure as a service clouds
, Article Peer-to-Peer Networking and Applications ; Volume 12, Issue 1 , 2019 , Pages 241-268 ; 19366442 (ISSN) ; Movaghar, A ; Mohsenzadeh, M ; Sharif University of Technology
Springer New York LLC
2019
Abstract
Cloud computing technology, which is a new model of service provisioning in distributed systems, has been raised as a way to execute workflow applications. To profit from this technology for executing workflow applications, it is necessary to develop workflow scheduling algorithms that consider different QoS parameters such as execution time and cost. Therefore, in this paper, we focus on two criteria: makespan (completion time) and execution cost of workflow application and propose a scheduling algorithm named CB-DT (Constrained Budget-Decreased Time) which aims to create a schedule that decreases the makespan while satisfying the budget constraint of the workflow application. In the...
Mesoporous silica nanoparticles (MCM-41) coated PEGylated chitosan as a pH-Responsive nanocarrier for triggered release of erythromycin [electronic resource]
, Article International Journal of Polymeric Materials and Polymeric Biomaterials ; 2014, Volume 63, Issue 13, Pages 692-697 ; Mazaheri Tehrani, Zahra ; Sharif University of Technology
Abstract
A pH-responsive drug delivery system based on core shell structure of mesoporous silica nanoparticle (MSN) and chitosan-PEG copolymer was prepared and characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscope (SEM), and high-resolution transmission microscope (HR-TEM) techniques. In order to improve compatibility MSN and drug, mesoporous nanosilica was modified by 3-aminopropyl triethoxysilane. The release of erythromycin (a macrolide antibiotic) as a model drug was investigated in two pHs, 7.4 and 5.5
Simulation and Implementation of Active Energy Management Algorithm on Residential Photovoltaic System with Storage
, M.Sc. Thesis Sharif University of Technology ; Abbaspour, Ali (Supervisor)
Abstract
In majority of the (standalone or grid-connected) PV Systems, predefined rule-based algorithms are utilized in order to manage and control the flow of power. The function of these algorithms is to send the generated energy from solar panels either to load for consumption, or to battery for storage, or to the grid for sale. Their performance is based on predefined instructions and regardless of load change and consumption patterns. Therefore the total efficiency of these systems depend greately upon individual user’s load type and consumption pattern. In current research, an optimum and dynamic energy management algorithm is proposed using dynamic programming (DP) method, in order to increase...
Power system stability improvement using self-tuning fuzzy logic controlled STATCOM
, Article EUROCON 2007 - The International Conference on Computer as a Tool, Warsaw, 9 September 2007 through 12 September 2007 ; December , 2007 , Pages 1444-1449 ; 142440813X (ISBN); 9781424408139 (ISBN) ; Zolghadri, M. R ; Ehsan, M ; Sharif University of Technology
2007
Abstract
This paper presents the application of a fuzzy logic controlled Static Compensator (STATCOM) to improve stability of power system. The nonlinear fuzzy logic controller is used to overcome the problems generated by different uncertainties exist in power systems. Different input variables are used to design the controller. Parameters of the proposed controller are adjusted by means of Neural Network techniques to improve performance of the system. Proposed controller is implemented on a single machine infinite bus system to confirm the performance of the controller through simulation results
Using Nonlinear Effects of Light for Optical Signal Processing
, M.Sc. Thesis Sharif University of Technology ; Kavehvash, Zahra (Supervisor)
Abstract
Ultrafast signal processing in time-domain with high resolution and reconfigura-bility is a challenging task. This paper, for the first time, introduces a time-varying metasurface consisting of graphene microribbon array for implementing time-lens in the terahertz domain. Given that the surface conductivity of graphene is proportional to the Fermi energy level in the THz regime, it is possible to change the phase property of the incident electromagnetic pulse by changing the Fermi level while the Fermi level itself is a function of voltage. Upon this fact, a quadratic temporal phase modulator, namely time-lens has been realized. This phase modulation is applied to the impinging signal in the...
Theoretical and Computational Investigation of Quantum Plasmonic Properties of Nanocluster Dimers
, M.Sc. Thesis Sharif University of Technology ; Jamshidi, Zahra (Supervisor)
Abstract
In today's era, metal nanoparticles play an important role in technologies emerging from different sciences, such as chemistry, physics, optics, material science, due to their unique characteristics. In the development of nanooptics science, it can be said that metal nanoparticles play an important role. The ability of conductive electrons collective oscillation causes surface charge density fluctuations in nanoparticles, this phenomenon is known as surface plasmons. Surface plasmons are surprisingly coupled with light and cause the significant increase in the intensity of optical fields induced in nanoparticles. Therefore, with the presence of localized surface plasmons or plasmon...
Theoretical Investigation of Ab-initio MD Approach to Increase the Efficiency and Accuracy of VCD Spectrum Calculation
, M.Sc. Thesis Sharif University of Technology ; Jamshidi, Zahra (Supervisor)
Abstract
Understanding of the Molecules is the main purpose of the chemistry. Ab-initio molecular dynamics (AIMD) as a branch of the computational chemistry, tries to give us a deep comprehension of the molecule, and its chemical, physical and optical activities. This comprehension, relies on the accuracy of quantum mechanics, in addition to the speed of the classical mechanics. The mixing of the quantum mechanics and the classical mechanics could simulate activities of the atoms in the time-domain, provided the mixing is done with precaution. This, in turn, helps us to forecast the response of a molecule in different situations, and also translating the macroscopic phenomena in a nanoscopic...
Investigation of Plasmonic Excitation in Carbonic Nanostructures Within Near-IR
, M.Sc. Thesis Sharif University of Technology ; Jamshidi, Zahra (Supervisor)
Abstract
To date, the plasmonic properties of many metallic and semi-conducting materials have been investigated and used in various industries. One of the plasmonic material categories that have always been considered is polycyclic aromatic hydrocarbon or PAH, whose plasmonic resonance energy depends on the charge state of the molecule. In this regard, it is easy to change the plasmonic resonance energy via changing the induced charge, which is a unique feature of the mentioned materials. In addition, plasmonic structures with excitations in the infrared region are able to enhance the vibration intensity of absorbed molecules by increasing the electric field around themselves. Therefore, they have...
Using Simulation-Optimization Approach for Fire Station Location and Vehicle Assignment Problem: a Case Study in Tehran, Iran
, M.Sc. Thesis Sharif University of Technology ; Amini, Zahra (Supervisor)
Abstract
In this research, the problem of locating fire stations and allocating equipment has been studied and a simulation-optimization approach has been presented to solve the problem. The mathematical models of this research were developed based on the idea of the randomness of the covered demand and the maximum expected coverage model. In these models, the issue of non-availability of equipment to cover accidents, the random nature of accidents, various fire incidents and the equipment needed to cover them are considered. Two mathematical models with deterministic and non-deterministic approach with different scenarios for demand are proposed. The non-deterministic model is developed with the aim...
Introducing An Integrated Framework For Solving The Fleet Planning Problem Using A Simulation-Optimization Approach
, M.Sc. Thesis Sharif University of Technology ; Amini, Zahra (Supervisor)
Abstract
One of the main concerns of industrial companies’ managers is providing an efficient logistics system. To achieve an efficient logistics system, the fleet planning problem is studied by many researchers in recent years. This problem consists of multiple sub-problems at three levels: operational, tactical, and strategic. These sub-problems are closely related to each other and need to be studied and addressed in an integrated manner. In this research, an attempt is made to provide an integrated framework to solve the vehicle routing problem (operational), outsourcing problem (tactical), and fleet composition problem (strategic). These problems have various uncertainties, including customer...
Effect of Initial Static Shear Stress on Undrained Cyclic Resistance of Well Graded, Medium Dense Gravelly Soils by Cyclic Triaxial Tests
, M.Sc. Thesis Sharif University of Technology ; Haeri, Mohsen (Supervisor)
Abstract
Softening and liquefaction of granular soils due to earthquakes have been a major cause for much destruction in preceding decades. This phenomenon mostly occurs in sandy soils, yet its occurrence has also been reported in gravelly soils in the last three decades. Despite the numerous researches which have investigated the undrained cyclic behavior of gravelly soils during earthquakes, there are still some aspects that need further study.This research investigates the effect of initial static shear stress on undrained cyclic resistance of a well graded, medium dense gravelly soil by conducting a series of cyclic triaxial tests. The 23 performed tests are categorized into 5 groups with...
Vibrational analysis of Ag, Cu and Ni nanobeams using a hybrid continuum-atomistic model
, Article International Journal of Mechanical Sciences ; Volume 165 , 2020 ; Azizi, B ; Nejat Pishkenari, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
An important issue in the study of the nanostructures behaviors is the surface effects, which increases with the increase of the surface-to-volume ratio. Continuum theories are capable of modeling structures at micro and larger scales with enough precision and low computational costs. However, these theories are unable to predict the mechanical properties of nanostructures accurately. On the other hand, due to their high precision, atomistic modeling techniques are extensively employed for the study of systems at nanoscale; however, computational costs of these techniques are relatively high. In this research, we aim to study the vibrational behavior of nanobeams made of three FCC metals;...
Analytical Modelling and Optimization of Disk Type, Slot Less Resolver
, M.Sc. Thesis Sharif University of Technology ; Nasiri Gheidari, Zahra (Supervisor)
Abstract
Resolvers, due to their robust structure, are widely used in automation systems. Among the types of resolvers, the accuracy of the Wound Rotor (WR) resolver in the occurrence of common mechanical errors is higher than other types of resolvers. therefore, in this thesis, an AFWRR is studied to improve the performance. Increasing the number of poles in WR resolvers is a good solution for increasing the accuracy of these electromagnetic position sensors. However, high-speed WR resolvers due to employing fractional slot windings suffer from rich sub-harmonics in the induced voltages. A common solution for suppressing the undesirable sub-harmonics is using multi-layer winding with appropriate...
A Survey on Searchable Symmetric Encryption Schemes
, M.Sc. Thesis Sharif University of Technology ; Khazaei, Shahram (Supervisor)
Abstract
Using “Searchable Encryption” enables us to encrypt the data, while preserving the possibility of running search queries. One of the most important applications of the mentioned is in Cloud Storage. As users do not trust the Cloud space, they are not inclined to store their data on the Could. The solution to this problem is of course, Cryptography. However, ordinary Cryptography methods, eliminate the data’s searchability. Hence, we need encryption schemes that code the data while retaining their searchability. So far, various schemes has been proposed that differ in their performance, security level, and usage. In this thesis, we aim to discuss and analyze these methods