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Routing, spectrum and modulation level assignment, and scheduling in survivable elastic optical networks supporting multi-class traffic
, Article Journal of Lightwave Technology ; Volume 36, Issue 23 , 2018 , Pages 5451-5461 ; 07338724 (ISSN) ; Beyranvand, H ; Salehi, J. A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
As elastic optical networks (EONs) are expected to convey high bitrate connections, a failure in these networks causes vast data losses. Thus, addressing the problem of survivability in EONs is of great importance. In this paper, survivability of an EON with multiclass traffic is investigated, where each traffic type needs specific protection mechanism and scheduling strategy. In particular, a connection request may demand for dedicated path protection, shared backup path protection, or restoration mechanism. Besides, it can tolerate a pre-determined delay and be scheduled at future time slots, referred to as advance reservation, or must be served immediately without any delay, referred to...
Crosstalk-aware routing, modulation level, core and spectrum assignment, and scheduling in sdm-based elastic optical networks
, Article 9th International Symposium on Telecommunication, IST 2018, 17 December 2018 through 19 December 2018 ; 2019 , Pages 160-165 ; 9781538682746 (ISBN) ; Beyranvand, H ; Salehi, J. A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
The transmission capacity of traditional single core fibers is reaching its upper bound. Space-division multiplexing (SDM) leveraging multi-core fibers is considered to be a promising solution for this problem. Elastic optical networks (EONs) with Multi-core fibers (MCF) are a kind of SDM-enabled EONs (SDM-EON) providing larger transmission capacity. However, the resource assignment in these networks becomes more complex due to inter-core crosstalk. Another important issue to be considered in future networks is the time domain behavior of incoming traffic which means considering Advance Reservation (AR) requests, in addition to regular Immediate Reservation (IR) requests. In this paper, the...
Crosstalk-aware resource allocation in survivable space-division-multiplexed elastic optical networks supporting hybrid dedicated and shared path protection
, Article Journal of Lightwave Technology ; Volume 38, Issue 6 , 15 March , 2020 , Pages 1095-1102 ; Beyranvand, H ; Salehi, J. A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
In this paper, the problem of routing, modulation level, core, and spectrum assignment (RMCSA) in space-division-multiplexed elastic optical networks (SDM-EONs) is studied. We formulate this problem as a mixed-integer linear programming (MILP), in which dedicated and shared path protection schemes are supported in SDM-EONs with multi-core fibers (MCFs) and the inter-core crosstalk of MCFs is strictly modeled. Furthermore, an efficient heuristic algorithm is proposed to solve the RMCSA problem in a large scale scenario. Numerical results reveal that the formulated MILP leads to lower spectrum usage compared to the alternative methods. Moreover, the proposed heuristic algorithm performs close...
Resource allocation in space division multiplexed elastic optical networks secured with quantum key distribution
, Article IEEE Journal on Selected Areas in Communications ; Volume 39, Issue 9 , 2021 , Pages 2688-2700 ; 07338716 (ISSN) ; Beyranvand, H ; Salehi, J. A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
Elastic Optical Network (EON) is a promising solution to address the high capacity, low latency, and flexibility requirements of the upcoming 5th-generation (5G) networks. Furthermore, Multi-Core Fibers (MCFs) and Space Division Multiplexing (SDM) technique can be utilized to overcome the capacity limitation of the conventional Single Mode Fibers (SMFs). On the other hand, Quantum Key Distribution (QKD) is an effective solution to address the security issues in 5G transport networks. In this paper, we investigate the performance of QKD over elastic optical networks with multi-core fibers and address the resource allocation problem for quantum and classical channels of QKD (QChs and CChs) and...
Designing Survivable Elastic Optical Networks to Support Multi-Class Traffic
, M.Sc. Thesis Sharif University of Technology ; Salehi, Javad (Supervisor) ; Beyranvand, Hamzeh (Supervisor)
Abstract
Recently, elastic optical networks have attracted high interest to provide more efficiency and scalability in optical core networks. Due to the high transmission rates and the importance of the transmitted data in these networks, a failure may cause vast data losses. Thus, addressing the problem of survivability in these networks is of great importance. According to different time domain behaviors and reliability requirements of incoming traffic, supporting different quality of services is another important concern. On the other hand, using multi-core fibers is a way to scale the network capacity to provide high-speed transmission services but there is a concern that the inter-core crosstalk...
Designing Survivable and Quantum Key Distribution Secured Elastic Optical Networks
, M.Sc. Thesis Sharif University of Technology ; Salehi, Jawad (Supervisor) ; Beyranvand, Hamzeh (Supervisor)
Abstract
Elastic optical networks, due to their key features including flexible spectrum allocation, ability to convey high bitrates, and distance adaptive modulation assignment are considered as a promising solution for providing higher capacity, more efficiency, and scalability in core optical networks.Furthermore, Multi-Core Fibers (MCFs) and Space Division Multiplexing (SDM) technique can be utilized to overcome the capacity limitation of the conventional Single Mode Fibers (SMFs). However, the inter-core crosstalk issue in MCFs should be addressed in the design of these networks.With the use of these technologies and, as a result, increasing the transmission rate in optical networks, the issue...
A novel hardware implementation for joint heart rate, respiration rate, and gait analysis applied to body area networks
, Article Proceedings - IEEE International Symposium on Circuits and Systems ; 2013 , Pages 1889-1892 ; 02714310 (ISSN) ; 9781467357609 (ISBN) ; Zamani, A. R ; Hallajian, M ; Ehsani, S. P ; Moghaddam, H. A ; Parsafar, A ; Shabany, M ; Sharif University of Technology
2013
Abstract
Continuous and remote monitoring of vital health-related and physical activity signs of a patient is one of the most important technology-oriented applications to monitor the health-care of ill individuals. In this paper, an innovative framework for a wireless Body Area Network (BAN) system, based on the IEEE 802.15.6 standard, with three types of sensors is proposed and implemented. These include Electrocardiogram (ECG), Force Sensitive Resistor (FSR) and Gyroscope. The proposed design is a novel implementation of an embedded system for the real-time processing and analyzing of the ECG signal, gait phases, and detection of the respiration rate from the ECG signal, by means of small...
Identifying and Rating Indicators for Measuring Iranian Entrepreneurship Ecosystem based on OECD Framework’s Domains with ANDE Method
, M.Sc. Thesis Sharif University of Technology ; Yavari, Elham (Supervisor) ; Sharif, Hossein (Co-Advisor)
Abstract
“Entrepreneurship ecosystem” is defined as the elements – individuals, organizations or institutions – apart from the individual entrepreneur that are conducive to, or inhibitive of, the choice of a person to become an entrepreneur, or the probabilities of his or her success following launch. Entrepreneurial businesses operate locally or regionally and are therefore subject to local or regional contextual influence. Moreover particularly in larger countries there can exist significant variation in industry structure and economic base across regions, emphasizing the importance of regional focus. Adopting appropriate policies at the regional level need to have a deep and accurate...
A Method for Incremental Learning of Stream Data
, Ph.D. Dissertation Sharif University of Technology ; Bagheri Shouraki, Saeed (Supervisor)
Abstract
Today, the pace of information generation, fast processing and instant decision-making is increasing. In this regard, one of the main needs in the field of data management and processing is stream data processing. Today's world needs new methods to deal with and analyze these data. Two of the most challenging aspects of data streams are (i) concept drift, i.e. evolution of data stream over time, which requires the ability to make timely decisions against the high speed of receiving new data; (ii) limited memory storage and the impracticality of using memory due to the large amount of data. Clustering is one of the common methods for processing data streams, without having basic knowledge...
Winner Strategies in a Simulated Stock Market
, Ph.D. Dissertation Sharif University of Technology ; Zamani, Shiva (Supervisor) ; Yavari, Elham (Supervisor)
Abstract
In this study, we explore the dynamics of the stock market using an agent-based simulation platform. Our approach involves creating a multi-strategy market where each agent considers both fundamental and technical factors when determining their strategy. The agents vary in their approach to these factors and the time interval they use for technical analysis. Our findings indicate that investing heavily in reducing the value–price gap was a successful strategy, even in markets where there were no trading forces to reduce this gap. Furthermore, our results remain consistent across various modifications to the simulation’s structure
Finite Element Analysis of Repair Welding Residual Stress in Pressure Vessels and Piping System
, M.Sc. Thesis Sharif University of Technology ; Farrahi, Gholamhossein (Supervisor)
Abstract
Repair welding is one of the most prevalent processes in repair and maintenance part of all industries. Amongst the issues of welding processes are residual stresses and distortions. Thus prediction of residual stresses and their distribution are important for designing welding procedure specifications. Circumferential butt weld is often used for joining steam and hot water lines in plants. Due to the intense concentration of heat in the welding, the regions near the weld line undergo severe thermal cycles. The thermal cycles cause non-uniform heating and cooling in the material, thus generating inhomogeneous plastic deformation and residual stresses in the weldment. The presence of residual...
Model for Optimal design of Energy Recovery System in Cement Plant
, M.Sc. Thesis Sharif University of Technology ; Sabouhi, Yadollah (Supervisor)
Abstract
The purpose of the present study is to develope an optimal model for analysis the impact of implementing a heat recovery system in a cement production line. For this goal, the energy reference system of a cement plant has been prepared, mass and energy balance sheets of the cement factory with dry production method, the characteristics of two high-energy streams have been identified in order to estimate the potential of heat recovery. Regarding the temperature range of the main hot streams, an appropriate cycle for generating electrical power from the lost heat, the Rankine cycle with organic fluid (ORC) has been formulated. The main question in the present project was how to relate the...
Deep Learning and Optimal Control
, M.Sc. Thesis Sharif University of Technology ; Fotouhi, Morteza (Supervisor)
Abstract
Our main focus in this thesis is on optimal control methods for the analysis of deep neural networks, such as the supervised learning problem. A neural network with a large number of layers can be modeled with an ordinary differential equation, whose control parameters play the role of intermediary functions in the neural network. This model gives us a more powerful tool to analyze the asymptotic behavior of the neural network. Also, in this thesis, the problems of numerical implementation of these methods will be discussed
Applying Gamification in Corporate Entrepreneurship Culture, Specially Missionary Organizations; Through SafirFilm Case Study
, M.Sc. Thesis Sharif University of Technology ; Yavari, Elham (Supervisor) ; Banki, Sara ($item.subfieldsMap.e)
Abstract
Although existing literature on organizational culture and its change process contains meaningful and rich theories but our studies show that there is no perfect and detailed framework on linking organizational culture change and corporate entrepreneurship culture. In addition to that, Gamification –defined as taking the game design elements into non-game contexts– is a fruitful and academically rich research area. Fortunately an idea proposed recently to explain a method for enhancements in organizational culture in general, and in corporate entrepreneurship culture in particularby Yavari and Jafarian based on using game mechanisms. In their paper "A Gamification-Based Method for Corporate...
Double Field Theory
, M.Sc. Thesis Sharif University of Technology ; Arfaei, Hesamaddin (Supervisor)
Abstract
Double Field Theory tries to incorporate T-duality, one of fundamental features of string theory, as a symmetry of a field Theory on a doubled space. It sets fields depend on winding mode conjugate coordinates as well as conventional space-time coordinates. In this review after presenting a brief introduction to string theory we investigate O(d,d,ℤ) duality group. Subsequently, we focus on Double Field Theory construction putting our attention on massless sector of string theory. We investigate on 2D nonlinear sigma model action in DFT and its gauge algebra. We follow this review by discussing constraints of DFT and Double Geometry. At the end we present some unsolved questions in this...
, M.Sc. Thesis Sharif University of Technology ; Modarres Yazdi, Mohammad (Supervisor)
Abstract
In electrical energy market, an economic game is running in which, power generating companies compete with each other in order to determine their suitable strategies and gain the highest possible profit. The literature shows the researchers actually use different algorithms to determine their suitable strategies but not Nash equilibrium method. These algorithms can not guarantee that the strategic equilibrium points can be found. In this research, the classic Nash method is used to determine GENCOs appropriate strategies and is simulated on some well known models (Cournot, Supply function equilibrium (SFE) and Bertrand), combined energy and reserve markets will be studied. The results of...
Ethylene Glycol Removal from Wastewater by Biological Means
, M.Sc. Thesis Sharif University of Technology ; Borgheei, Mahdi (Supervisor)
Abstract
In this research, MBBR was used to study petrochemical and gas refinery industry's low strength wastewater COD removal for reuse purposes. Reactor's feed was synthesized based on data analysis conducted by fourth wastewater treatment facility operating in phases 6,7 and 8. Inlet COD was 70 mg/L and this COD was provided by different portions of Mono ethylene glycol and Tri ethylene glycol. COD removal was studied under 1, 2 and 3 hours hydraulic retention time. Reactor's feed was provided with COD ratio of ( 〖COD〗_MEG/〖COD〗_total ) 65%, 60% and 50%. For the first time, hybrid combination of activated sludge system and MBBR was carried out and recycle stream was used in this system. The...
Aging behavior and tensile properties of squeeze cast AL 6061/SIC metal matrix composites
, Article Scientia Iranica ; Volume 11, Issue 4 , 2004 , Pages 392-397 ; 10263098 (ISSN) ; Seyed Reihani, S. M ; Sharif University of Technology
Sharif University of Technology
2004
Abstract
In this work, the production and properties of Al 6061/SiC composites, made using a squeeze casting method, were investigated. SiC preforms were manufactured by mixing SiC powder, having a 16 and 22 pm particle size, with colloidal silica as a binder. 6061 Al melt was squeeze cast into the pores of the SiC preform to manufacture a DRA composite containing 30v/o reinforcement. The aging behavior, tensile properties and fracture mechanism of the cast material were studied. The results show that higher hardness, yield strength, tensile strength and Young's modulus can be obtained by the addition of SiC particles to 6061 Al alloy, whereas tensile elongation decreases. This is mainly caused by a...
Investigating the Effect of Chemical Composition on the Anisotropy of Solid-Liquid Interfacial Energy of Nickel-Niobium Alloy
, M.Sc. Thesis Sharif University of Technology ; Tavakoli, Rouhollah (Supervisor)
Abstract
Although the anisotropy of the solid-liquid interfacial free energy for most metal alloys is small, this anisotropy plays a significant role in the growth rate, morphology, and preferred crystallographic directions in dendritic growth. In recent research, the binary nickel-niobium alloy has been suggested as a suitable substitute for studying the solidification behavior of the superalloy Inconel 718. In this study, using molecular dynamics simulation with the LAMMPS software, pure nickel and Ni-%1Nb, Ni-%5Nb, and Ni-%10Nb alloys were examined (composition is based on atomic percent). After equilibrating the liquid and solid phases at the melting temperature, the interfacial phase was studied...
Optimal space coverage with white convex polygons
, Article Journal of Combinatorial Optimization ; Dec , 2014 ; 13826905 ; Fazli, M ; Ghodsi, M ; Safari, M ; Sharif University of Technology
2014
Abstract
Assume that we are given a set of points some of which are black and the rest are white. The goal is to find a set of convex polygons with maximum total area that cover all white points and exclude all black points. We study the problem on three different settings (based on overlapping between different convex polygons): (1) In case convex polygons are permitted to have common area, we present a polynomial algorithm. (2) In case convex polygons are not allowed to have common area but are allowed to have common vertices, we prove the NP-hardness of the problem and propose an algorithm whose output is at least (Formula presented.). (3) Finally, in case convex polygons are not allowed to have...