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    Identification Of Surrogate Models for Hybrid Distributed Parameters Systems Using Machine Learning Algorithms

    , M.Sc. Thesis Sharif University of Technology Taghizadeh, Mohammad Javad (Author) ; Bozorgmehry Boozarjomehry, Ramin (Supervisor)
    Abstract
    In various industries, particularly in the process industries, computational fluid dynamics (CFD) stands as the predominant method for simulating distributed systems. In these methods, discretization of system geometry and partial differential equations is necessary, resulting in a system of algebraic or ordinary differential equations, or a combination thereof. The significant computational demands arising from the extensive number of equations derived from dynamic system simulations highlight the necessity for substantial processing and computing power. The objective of this project is to reduce the computational load associated with solving these equations. It focuses on utilizing machine... 

    A Formal Semantics for CORBA Interface Definition Language

    , M.Sc. Thesis Sharif University of Technology Sajjadi, Marjan (Author) ; Izadi, Mohammad (Supervisor)
    Abstract
    Common Object Request Broker Architecture (CORBA) is a standard for hybrid applications that is designed and supported by Object Management Group (OMG). This standard defines protocols and Relational Data Model Objects / Services which can be connected into heterogeneous software (written in different languages). So we can use CORBA to share the distributed object platform, without worrying about where they are located or who has designed them. CORBA can package the codes (in some programming languages) and add the packaging information, such as the ability to execute the codes and how to implement them. So this package or object code can execute some other programs or CORBA objects that... 

    Private Distributed Computing for Machine Learning Algorithms

    , M.Sc. Thesis Sharif University of Technology Mousavi, Mohammad Hossein (Author) ; Maddah-Ali, Mohammad Ali (Supervisor) ; Mirmohseni, Mahtab (Co-Supervisor)
    Abstract
    In this thesis, we argue that in many basic algorithms for machine learning, including support vector machine (SVM) for classification, principal component analysis (PCA) for dimensionality reduction, and regression for dependency estimation, we need the inner products of the data samples, rather than the data samples themselves. Motivated by the above observation, we introduce the problem of private inner product retrieval for distributed machine learning, where we have a system including a database of some files, duplicated across some non-colluding servers. A user intends to retrieve a subset of specific size of the inner products of the data files with minimum communication load, without... 

    Distribution System Reliability Improvement with Design of a Novel Demand Response Program

    , M.Sc. Thesis Sharif University of Technology Ghasemifard, Mohammad Hassan (Author) ; Abbaspour Tehrani Fard, Ali (Supervisor) ; Fotuhi Firouzabad, Mahmud (Co-Advisor)
    Abstract
    This paper proposes a novel real-time pricing tariff design aiming at reducing the operation cost of distribution system. A customer base-line load (CBL) is established for each participant. It let the customer to have less exposure with RTP volatile prices.The tariff charges the consumption above the CBL an hourly varying price. It credits the consumption below the CBL another hourly varying price.The proposed tariff provides the participant with more incentive and discount prices to encourage it to consume more efficient. The optimal prices are determined and announced a day in advance but can change in the next day with a short notice.The response of customers to the tariff prices is... 

    Loss Management in Smart Distribution Systems

    , Ph.D. Dissertation Sharif University of Technology Ghofrani Jahromi, Zeinab (Author) ; Ehsan, Mehdi (Supervisor)
    Abstract
    One of the topics that has been given great consideration after restructuring and smart grid emergence, is loss management. This subject is specifically important in distribution systems, which have been reported to have 70% of the total loss in power systems. In this thesis, distribution loss is studied and its affecting factors are analyzed. Then loss optimization and loss cost allocation to distribution consumers are studeid. In order to acheive these two goals, it is neccessary for the distribution system to have the capabilities of a smart grid. The subjectof distribution reconfiguration is duiscussed as one of the loss reduction methods. Traditional reconfiguration problem trend... 

    Design and Analysis of Algorithms for Distributed Private Function Retrieval

    , M.Sc. Thesis Sharif University of Technology Khalesi, Ali (Author) ; Mirmohseni, Mahtab (Supervisor) ; Maddah Ali, Mohammad Ali (Supervisor)
    Abstract
    In the problem of Distributed Multi¬User Secret Sharing (DMUSS), in which K users are connected through some error¬free links to N distinct storage nodes with the same size M information unit, the users desire to retrieve their corresponding secret message through an arbitrary set of accessible storage nodes. A trusted master node, which knows all of the secret messages transmits correctly and privately, the messages with a means of coding. The capacity of Distributed Multi¬User Secret Sharing is the supremum of all achievable schemes satisfying privacy and correctness conditions. In this thesis we have investigated two notions of privacy namely, individual and joint privacy. Individual... 

    A Blockchain Based System to Ensure Transparency and Originality in Supply Chain

    , M.Sc. Thesis Sharif University of Technology Ghomi Avili, Morteza (Author) ; Akhavan Niaki, Taghi (Supervisor)
    Abstract
    Emergence of crypto-currency and blockchain technology revolutionize supply chain processes. In addition, customer needs for more information on products or services from origin to destination, highlights the necessity of transparency, originality and traceability in supply chains. This research is aimed to develop a blockchain based system ascertaining supply chain transparency and originality. To this aim, a joint pricing and closed-loop supply chain network design problem is selected as a good platform to implement it. Due to increasing concerns on environmental issues and maximizing job opportunities, sustainability is also considered in the proposed problem. To ascertain transparency... 

    Dynamic control of supported macro/micro-tubes conveying magnetic fluid utilizing intelligibly designed axially functionally graded materials

    , Article International Journal of Computer Integrated Manufacturing ; 2021 ; 0951192X (ISSN) Du, J ; Mirtalebi, S. H ; Ahmadian, M. T ; Cao, Y ; Suhatril, M ; Assilzadeh, H ; Sharif University of Technology
    Taylor and Francis Ltd  2021
    Abstract
    In this study, dynamic modeling of an elbow axially functionally graded (AFG) macro/micro-tube carrying magnetic flow with different cross-sections is considered. Parametric optimization is performed for vibration suppression of such fluid-interaction systems. Implementing computer simulations, passive vibration control procedures, along with the effect of AFG materials and magnetic properties of the fluid as well as precisely manufactured geometry of the system, is investigated. It is assumed that the material characteristics of the system vary in the longitudinal direction based on exponential and power-law distribution profiles. Influence of the downstream inclination angle and... 

    Dynamic control of supported macro/micro-tubes conveying magnetic fluid utilizing intelligibly designed axially functionally graded materials

    , Article International Journal of Computer Integrated Manufacturing ; Volume 35, Issue 4-5 , 2022 , Pages 345-358 ; 0951192X (ISSN) Du, J ; Mirtalebi, S. H ; Ahmadian, M.T ; Cao, Y ; Suhatril, M ; Assilzadeh, H ; Sharif University of Technology
    Taylor and Francis Ltd  2022
    Abstract
    In this study, dynamic modeling of an elbow axially functionally graded (AFG) macro/micro-tube carrying magnetic flow with different cross-sections is considered. Parametric optimization is performed for vibration suppression of such fluid-interaction systems. Implementing computer simulations, passive vibration control procedures, along with the effect of AFG materials and magnetic properties of the fluid as well as precisely manufactured geometry of the system, is investigated. It is assumed that the material characteristics of the system vary in the longitudinal direction based on exponential and power-law distribution profiles. Influence of the downstream inclination angle and... 

    Estimating parameters with pre-specified accuracies in distributed parameter systems using optimal experiment design

    , Article International Journal of Control ; Volume 89, Issue 8 , 2016 , Pages 1533-1553 ; 00207179 (ISSN) Potters, M. G ; Bombois, X ; Mansoori, M ; Van Den Hof, P. M. J ; Sharif University of Technology
    Taylor and Francis Ltd 
    Abstract
    Estimation of physical parameters in dynamical systems driven by linear partial differential equations is an important problem. In this paper, we introduce the least costly experiment design framework for these systems. It enables parameter estimation with an accuracy that is specified by the experimenter prior to the identification experiment, while at the same time minimising the cost of the experiment. We show how to adapt the classical framework for these systems and take into account scaling and stability issues. We also introduce a progressive subdivision algorithm that further generalises the experiment design framework in the sense that it returns the lowest cost by finding the... 

    Day-ahead resource scheduling in distribution networks with presence of electric vehicles and distributed generation units

    , Article Electric Power Components and Systems ; Volume 47, Issue 16-17 , 2019 , Pages 1450-1463 ; 15325008 (ISSN) Shafiee, M ; Ghazi, R ; Moeini Aghtaie, M ; Sharif University of Technology
    Taylor and Francis Inc  2019
    Abstract
    In this paper a new framework for scheduling of available resources in the distribution networks is developed. In this respect attempts are focused on interactions between charging/discharging profiles of electric vehicles (EVs) and output power of distributed generation units. To reach this goal, the proposed framework is designed as a two-stage optimization procedure. In the first stage, the charging/discharging schedules of EVs are extracted running a linear programing optimization problem taking into account the EV users' constraints and requirements. The usage profiles of the DG units, strategy of buying electricity from the market and also the final charging/discharging patterns of the... 

    Rolling contact mechanics of graded coatings involving frictional heating

    , Article Acta Mechanica ; Volume 230, Issue 6 , 2019 , Pages 1981-1997 ; 00015970 (ISSN) Nili, A ; Adibnazari, S ; Karimzadeh, A ; Sharif University of Technology
    Springer-Verlag Wien  2019
    Abstract
    The two-dimensional thermoelastic tractive rolling contact problem for a half-plane which is coated with a functionally graded material (FGM), under the plane strain deformation, is studied in this paper. A rigid cylinder rolls over the surface of an FGM coating with constant translational velocity, generating frictional heating in the slip zones of the contact area. Thermomechanical properties of the FGM vary exponentially along the thickness direction. It is assumed that the contact area consists of a central stick zone and two slip zones of the same sign. The transfer matrix method and Fourier integral transform technique are used to achieve a system of two Cauchy singular integral... 

    A safe stopping protocol to enable reliable reconfiguration for component-based distributed systems

    , Article 6th International Conference on Fundamentals of Software Engineering, FSEN 2015, 22 April 2015 through 24 April 2015 ; Volume 9392 , November , 2015 , Pages 100-109 ; 03029743 (ISSN) ; 9783319246437 (ISBN) Ghafari, M ; Heydarnoori, A ; Haghighi, H ; Sharif University of Technology
    Springer Verlag  2015
    Abstract
    Despite the need for change, highly available software systems cannot be stopped to perform changes because disruption in their services may consequent irrecoverable losses. Current work on runtime evolution are either too disruptive, e.g., "blackouts" in unnecessary components in the quiescence criterion approach or presume restrictive assumptions such as the "black-box design" in the tranquility approach. In this paper, an architecture-based approach, called SAFER, is proposed which provides a better timeliness by relaxing any precondition required to start reconfiguration. We demonstrate the validity of the SAFER through model checking and a realization of the approach on a component... 

    An agent-based approach for market-based customer reliability enhancement in distribution systems

    , Article 16th International Conference on Distributed Computing and Artificial Intelligence, DCAI 2019, 26 June 2019 through 28 June 2019 ; Volume 1004 , 2020 , Pages 171-176 Ebrahimi, M ; Ebrahimi, M ; Abdi, B ; Sharif University of Technology
    Springer Verlag  2020
    Abstract
    These days, considering the importance of reliability in industries, utilities’ role for preparing high levels of reliability becomes more important. This can be done by adding numbers of switches and Tie switches which impose high expenses to system. These expenditures should be provided by customers. Level of reliability in different points of network is different. So customers which pay more, receive higher level of reliability. If a customer raises its payment, utility change the location of switches in order to raise level of reliability of that customer. all customers change their payment and then utility fixes the switches at a point that all customers reach their favorable... 

    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) Ghafouri, R ; 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) Ghafouri, R ; 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... 

    Dynamic Gossip

    , Article Bulletin of the Iranian Mathematical Society ; Volume 45, Issue 3 , 2019 , Pages 701-728 ; 10186301 (ISSN) van Ditmarsch, H ; van Eijck, J ; Pardo, P ; Ramezanian, R ; Schwarzentruber, F ; Sharif University of Technology
    Springer International Publishing  2019
    Abstract
    A gossip protocol is a procedure for spreading secrets among a group of agents, using a connection graph. The goal is for all agents to get to know all secrets, in which case we call the execution of the protocol successful. We consider distributed and dynamic gossip protocols. In distributed gossip, the agents themselves instead of a global scheduler determine whom to call. In dynamic gossip, not only secrets are exchanged but also telephone numbers (agent identities). This results in increased graph connectivity. We define six such distributed dynamic gossip protocols, and we characterize them in terms of the topology of the graphs on which they are successful, wherein we distinguish... 

    Toward operational resilience of smart energy networks in complex infrastructures

    , Article Advances in Intelligent Systems and Computing ; Volume 1123 , 2020 , Pages 203-228 Taheri, B ; Jalilian, A ; Safdarian, A ; Moeini Aghtaie, M ; Lehtonen, M ; Sharif University of Technology
    Springer  2020
    Abstract
    Smart energy systems can mitigate electric interruption costs provoked by manifold disruptive events via making efforts toward proper pre-disturbance preparation and optimal post-disturbance restoration. In this context, effective contingency management in power distribution networks calls for contemplating disparate parameters from interconnected electric and transportation systems. This chapter, while considering transportation issues in power networks’ field operations, presents a navigation system for pre-positioning resources such as field crews and reconfiguring the network to acquire a more robust configuration in advance of the imminent catastrophe. Also, after the occurrence of the... 

    Crosstalk reduction in hybrid quantum-classical networks

    , Article Scientia Iranica ; Volume 23, Issue 6 , 2016 , Pages 2898-2907 ; 10263098 (ISSN) Bahrani, S ; Razavi, M ; Salehi, J. A ; Sharif University of Technology
    Sharif University of Technology  2016
    Abstract
    In this paper, we propose and investigate several crosstalk reduction techniques for hybrid quantum-classical dense-wavelength-division-multiplexing systems. The transmission of intense classical signals alongside weak quantum ones on the same fiber introduces some crosstalk noise, mainly due to Raman scattering and non-ideal channel isolation, that may severely affect the performance of quantum key distribution systems. We examine the conventional methods of suppressing this crosstalk noise, and enhance them by proposing an appropriate channel allocation method that reduces the background crosstalk effectively. Another approach proposed in this paper is the usage of orthogonal frequency... 

    Optimality of network marketing integrated in a dual-channel distribution system

    , Article Scientia Iranica ; Volume 25, Issue 5E , 2018 , Pages 2838-2851 ; 10263098 (ISSN) Modarres, M ; Shafiei, M ; Sharif University of Technology
    Sharif University of Technology  2018
    Abstract
    This paper provides a framework to study the integration of network marketing in a dual-channel distribution system. We develop an approach to optimize the main decision variables of this system simultaneously. These decision variables include the price paid by the customers of both channels, confidence level, the effort level of active distributors of network marketing, and wholesale price. Although both channels compete with each other, it is vital to have a balanced pricing system to keep them motivated. However, the prices in network marketing and traditional retailer system are not necessarily equal due to the differences in their nature. Furthermore, it is also required to develop an...