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    Scaling of macroscopic superpositions close to a quantum phase transition

    , Article Physical Review B - Condensed Matter and Materials Physics ; Volume 93, Issue 19 , 2016 ; 10980121 (ISSN) Abad, T ; Karimipour, V ; Sharif University of Technology
    American Physical Society  2016
    Abstract
    It is well known that in a quantum phase transition (QPT), entanglement remains short ranged [Osterloh et al., Nature (London) 416, 608 (2005)NATUAS0028-083610.1038/416608a]. We ask if there is a quantum property entailing the whole system which diverges near this point. Using the recently proposed measures of quantum macroscopicity, we show that near a quantum critical point, it is the effective size of macroscopic superposition between the two symmetry breaking states which grows to the scale of system size, and its derivative with respect to the coupling shows both singular behavior and scaling properties  

    Critical slowing down of multiatom entanglement by Rydberg blockade

    , Article Physical Review A ; Volume 98, Issue 2 , 2018 ; 24699926 (ISSN) Abad, T ; Mølmer, K ; Sharif University of Technology
    American Physical Society  2018
    Abstract
    Laser excitation pulses that lead to perfect adiabatic state transfer in an ensemble of three-level ladder atoms lead to highly entangled states of many atoms if their highest excited state is subject to Rydberg blockade. Solution of the Schrödinger equation shows that it is increasingly difficult to ensure the adiabatic evolution as the number of atoms increases. A diminishing energy gap, significant variations in collective observables, and increased work fluctuations link the critical slowing down of the adiabatic evolution with a quantum-phase-transition-like behavior of the system. © 2018 American Physical Society  

    Failure analysis of a gas turbine compressor in a thermal power plant

    , Article Journal of Failure Analysis and Prevention ; Volume 13, Issue 3 , 2013 , Pages 313-319 ; 15477029 (ISSN) Masoumi Khalil Abad, E ; Farrahi, G. H ; Masoumi Khalil Abad, M ; Zare, A. A ; Parsa, S ; Sharif University of Technology
    2013
    Abstract
    This study presents the results of failure analysis of a 28 MW gas turbine at the Rei electrical power plant. The gas turbine failed during the shutdown period and near its second natural frequency at 4200 rpm. Initial inspections revealed that the compressor disk of stage 15 was fractured, and all of the stationary and rotary blades of stages 14-18 of the compressor had been detached or broken from the dovetail region of the disks. The fracture roots were investigated by performing finite element modeling and fractography analysis. It was shown that a crack was initiated from the disk edge on its interface with the rotor shaft and was propagated under cyclic loading. As a result of the... 

    Macroscopic Superposition in Quantum Systems

    , Ph.D. Dissertation Sharif University of Technology Abad, Tahereh (Author) ; Karimipour, Vahid (Supervisor)
    Abstract
    Quantum mechanics provides a deep understanding of atoms and their interaction with light. As long as we consider only microscopic systems on the scale of an atomic radius, objections to quantum properties such as quantum superposition are nevertheless rare, mainly because of the overwhelming experimental evidence. When it comes to macroscopic systems, many things are not clear anymore. For example,everyday objects of macroscopic size do not exist in superposition of their different states. The reason is that a quantum system interacts with its environment locally,which destroys non-local quantum correlation within the system, larger objects interact with the environment more intensively and... 

    Power of quantum channels for creating quantum correlations

    , Article Physical Review A - Atomic, Molecular, and Optical Physics ; Volume 86, Issue 6 , 2012 ; 10502947 (ISSN) Abad, T ; Karimipour, V ; Memarzadeh, L ; Sharif University of Technology
    2012
    Abstract
    Local noise can produce quantum correlations on an initially classically correlated state, provided that it is not represented by a unital or semiclassical channel. We find the power of any given local channel for producing quantum correlations on an initially classically correlated state. We introduce a computable measure for quantifying the quantum correlations in quantum-classical states, which is based on the noncommutativity of ensemble states in one party of the composite system. Using this measure we show that the amount of quantum correlations produced is proportional to the classical correlations in the initial state. The power of an arbitrary channel for producing quantum... 

    Sequentially generated entanglement, macroscopicity, and squeezing in a spin chain

    , Article Physical Review A ; Volume 96, Issue 4 , 2017 ; 24699926 (ISSN) Abad, T ; Mølmer, K ; Karimipour, V ; Sharif University of Technology
    2017
    Abstract
    We study quantum states generated by a sequence of nearest neighbor bipartite entangling operations along a one-dimensional chain of spin qubits. After a single sweep of such a set of operations, the system is effectively described by a matrix product state (MPS) with the same virtual dimension as the spin qubits. We employ the explicit form of the MPS to calculate expectation values and two-site correlation functions of local observables, and we use the results to study fluctuations of collective observables. Through the so-called macroscopicity and the squeezing properties of the collective spin variables they witness the quantum correlations and multiparticle entanglement within the... 

    Comparative Study on Stability of Concrete Gravity Dams Using Rigid and Flexible Approach

    , M.Sc. Thesis Sharif University of Technology jalili Sadr Abad, Mohammad (Author) ; Ghaemian, Mohsen (Supervisor)
    Abstract
    One of most important type of dams are concrete gravity dams, This structures maintain their stability against the load from their weight. The study of stability of dams is very important issue because Iran is placed on a seismic zone and instability of constructed dams will cause many problems for us. There are two method in study of concrete gravity dams: in first method which is named rigid approach the body of dam consider as a rigid body and by equilibrium equations and traditional strength of material concepts the safety factors of stability and stresses are determined. In second method that is named flexible approach, we should prepare a finite element method from the dam, reservoir... 

    Intrusion Detection in Wireless Sensor Networks Using Incremental Emotional Intelligence Models

    , M.Sc. Thesis Sharif University of Technology Bayat, Firoozeh (Author) ; Hashemi Mohammad Abad, Saeid (Supervisor)
    Abstract
    Wireless Sensor Networks (WSNs) are rapidly emerging as an important area in mobile computing research. Applications of WSNs are numerous and growing, some of them are even highly critical, like military or safety applications. Security measures must be applied to protect the network from a variety of attacks. Since no intrusion prevention measure is perfect, intrusion detection becomes an important second wall to protect the network. WSNs have unique nature which is different from other kinds of networks. In this project, we examine the characteristics and vulnerabilities of WSNs and propose a new intrusion detection model to protect the network security. In this work we have not only... 

    Designing a Dynamic Model for Human Resource Training and Development in Iran Electric Power Industry

    , M.Sc. Thesis Sharif University of Technology Dehghani Eshrat Abad , Meisam (Author) ; Mahlooji, Hashem (Supervisor)
    Abstract
    Nowadays Human Resource Management (HRM) has a critical and fundamental importance in organization management. In the beginning and middle of 20th century and even in the last decades of that century financial investments were important in different economic sectors and industries, but in the beginning of 21th century human resource and training is one of the most fundamental issues in all of economic sectors and industries, especially in power industry. Following this point of view, people with appropriate education and qualifications should be employed in power industry. These employees should be skillfully able of working with complicated technology of power industry as well as being... 

    Development of an EPFC-Based Method Engineering Environment for Assembly-Based Construction of Agile Methodologies

    , M.Sc. Thesis Sharif University of Technology Shakeri Hossein Abad, Zahra (Author) ; Ramsin, Raman (Supervisor)
    Abstract
    Methodology engineering is a branch of software engineering which deals with the design, development, and modification of methodologies, and the techniques and tools for developing information systems. Methodology engineering requirements demand the support of Computer Aided Methodology Engineering (CAME) tools. Recently, method engineering focus has shifted towards Situational Method Engineering (SME); i.e. context-specific methodology development. The emergence of SME approaches has brought about various methods for methodology development; including ad hoc, paradigm-based, extension-based and assembly-based approaches. In the assembly-based strategy, appropriate method chunks are... 

    Probabilistic optimal power flow in correlated hybrid wind-PV power systems: A review and a new approach

    , Article Renewable and Sustainable Energy Reviews ; Vol. 41 , 2014 , pp. 1437-1446 ; ISSN: 13640321 Aien, M ; Rashidinejad, M ; Firuz-Abad, M. F ; Sharif University of Technology
    2014
    Abstract
    Hastening the power industry reregulation juxtaposed with the unprecedented utilization of uncertain renewable energies (REs), faces power system operation with sever uncertainties. Consequently, uncertainty assessment of system performance is an obligation. This paper reviews the probabilistic techniques used for probabilistic optimal power flow (P-OPF) studies and proposes a novel and powerful approach using the unscented transformation (UT) method. The heart of the proposed method lies in how to produce the sampling points. Appropriate sampling points are chosen to perform the P-OPF with a high degree of accuracy and less computational burden compared with features of other existing... 

    Determination of Maximum and Optimal Penetration Level of Distributed Generation in Distributed Systems

    , M.Sc. Thesis Sharif University of Technology Seydali Seyf Abad, Mohammad (Author) ; Parniani, Mostafa (Supervisor)
    Abstract
    Nowadays, development of renewable electricity generation technologies, the advent of small efficient generators and increasing number of grid-connected consumers, have caused increasing interest in energy production next to the consumers locations. Distributed generation (DG) is often defined as small-scale generators that produce several kilowatts to tens of megawatts of electricity. One primary reason for using DG is its potential to reduce power losses in transmission and distribution networks. Several loss reduction methods such as capacitor placement, network reconfiguration and load management are used in distribution systems. Employing DG results in the highest loss reduction and... 

    Probabilistic optimal power flow in correlated hybrid wind-PV power systems: A review and a new approach

    , Article Renewable and Sustainable Energy Reviews ; Volume 41 , January , 2015 , Pages 1437-1446 ; 13640321 (ISSN) Aien, M ; Rashidinejad, M ; Firuz Abad, M. F ; Sharif University of Technology
    Elsevier Ltd  2015
    Abstract
    Hastening the power industry reregulation juxtaposed with the unprecedented utilization of uncertain renewable energies (REs), faces power system operation with sever uncertainties. Consequently, uncertainty assessment of system performance is an obligation. This paper reviews the probabilistic techniques used for probabilistic optimal power flow (P-OPF) studies and proposes a novel and powerful approach using the unscented transformation (UT) method. The heart of the proposed method lies in how to produce the sampling points. Appropriate sampling points are chosen to perform the P-OPF with a high degree of accuracy and less computational burden compared with features of other existing... 

    Vehicle longitudinal velocity estimation during the braking process using unknown input Kalman filter

    , Article Vehicle System Dynamics ; Volume 53, Issue 10 , Jul , 2015 , Pages 1373-1392 ; 00423114 (ISSN) Moaveni, B ; Khosravi Roqaye Abad, M ; Nasiri, S ; Sharif University of Technology
    Taylor and Francis Ltd  2015
    Abstract
    In this paper, vehicle longitudinal velocity during the braking process is estimated by measuring the wheels speed. Here, a new algorithm based on the unknown input Kalman filter is developed to estimate the vehicle longitudinal velocity with a minimum mean square error and without using the value of braking torque in the estimation procedure. The stability and convergence of the filter are analysed and proved. Effectiveness of the method is shown by designing a real experiment and comparing the estimation result with actual longitudinal velocity computing from a three-axis accelerometer output  

    On the Performance Assessment and Parametric Study of Pre-stressed Concrete Doms Behavior

    , M.Sc. Thesis Sharif University of Technology Modarres Bostan Abad, Soheil (Author) ; Mofid, Masoud (Supervisor)
    Abstract
    Today, with the replacement of the old method of force-based design by the new method of performance-based design in structural and earthquake engineering, many structural and earthquake researchers have focused in their studies on this area. The performance-based design aims at enabling engineers to design structures with predictable performance. Designing space structures has particular complexities. In space structures, the failure of a structural member does not necessarily mean the failure of the entire structure, because the redistribution of power will occur between the adjacent members after the failure of a member and the structure can thus have further support capacity. Similarly,... 

    Preparation and Investigation of Ziegler-natta Catalyst with Nano MoS2 Support in UHMWPE Synthesis

    , M.Sc. Thesis Sharif University of Technology Amini, Majed (Author) ; Ramazani Saadat Abad, Ahmad (Supervisor)
    Abstract
    Ultra high molecular weight polyethylene has attracted the attention of numerous researchers and industries. This polymer due to its strong properties can be used in advanced military industries, medical engineering and cases in which high strength and high abrasion resistance is required. Present study aims to fabricate UHMWPE/Molybdenum disulfide composites, using in-situ polymerization. Before carrying out the polymerization process, nanoparticles of molybdenum disulfide underwent various processes such as oxidation, pickling, ultrasonic and thermal shock, in order to increase the interlayer distance and creating functional groups on the surface, then various analyzes, such as XRD, FESEM,... 

    Elastic Responses of a Half-Space Reinforced by a Buried Extensible Membrane under Internal Loading

    , M.Sc. Thesis Sharif University of Technology Ahmadi Kamal Abad, Kasra (Author) ; Eskandari, Morteza (Supervisor)
    Abstract
    In order to improve mechanical properties and increase the load capacity of soil so many different methods are innovated and utilized. Through This variety we can mention cement and asphalt concrete pavements which are the most common methods, cement sprinkling for consolidation of inclined surfaces and utilizing geotextiles and geomembranes which are recent methods. As far as a method becomes more common in industry, analytical study on effect of these methods on soil properties drew more attention in researches.In this research a homogenous elastic half-space is reinforced by an extensible thin plate and studied under various loads. The plate is considered as a buried infinite plane with... 

    PELAMIS’s Hydro Dynamical Analyses and Mechanism Design of Wave Energy Converter Device (Semi-PELAMIS)

    , M.Sc. Thesis Sharif University of Technology Saeidi Hamid Abad, Mohammad (Author) ; AbbasPour, Majid (Supervisor)
    Abstract
    Pelamis is a semi-submersible device that can extract wave energy and converters that to electrical power. It has 5 cylindrical structure that connects through the joints. This device takes the shape of wave and the wave forces tubes to had angular relative motion together. The Main task of this device is to convert the angular movements of tubes to the Linear movement of pistons. External mechanism called the energy capture device are responsible for absorbing wave energy through angular movements, and then the internal mechanism, called the Power Take-Off, are responsible for converting this energy into the electrical power for use in the electricity grid. This device was designed and... 

    Towards tool support for situational engineering of agile methodologies

    , Article Proceedings - Asia-Pacific Software Engineering Conference, APSEC, 30 November 2010 through 3 December 2010, Sydney, NSW ; 2010 , Pages 326-335 ; 15301362 (ISSN) ; 9780769542669 (ISBN) Shakeri Hossein Abad, Z ; Hasani Sadi, M ; Ramsin, R ; Sharif University of Technology
    2010
    Abstract
    Various agile software development methodologies, practices, and techniques have been proposed in the last decade; some present novel ideas, while many are simply made up of tasks and techniques borrowed from prominent agile methodologies. Each of these methodologies prescribes a set of practices and techniques which are deemed appropriate for application in a specific context. However, there exists no single method which fits all project situations. This has resulted in the advent of Situational Method Engineering (SME) approaches, which are used for developing software methodologies that are tailored to fit the specific circumstances of the project situation at hand. Since tool support has... 

    Application of bat optimization algorithm in optimal power flow

    , Article 24th Iranian Conference on Electrical Engineering, ICEE 2016, 10 May 2016 through 12 May 2016 ; 2016 , Pages 793-798 ; 9781467387897 (ISBN) Delkhosh Abatari, H ; Seyf Abad, M. S ; Seifi, H ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2016
    Abstract
    In this paper, Bat Algorithm is proposed to solve the Optimal Power Flow (OPF) problem. The approach employs a Meta heuristic optimization algorithm called bat optimization algorithm to determine the optimal settings of control variables of OPF problem. The performance of proposed method examined on the IEEE 9, 14, 30 and 57-buses test systems with fuel cost minimization as the objective function. The numerical results are compared to those of Particle Swarm Optimization (PSO), Harmony Search (HS) and Cuckoo algorithms. Simulation results obtained from the proposed approach demonstrate that this method provide effective and robust high-quality answer for the OPF problem. © 2016 IEEE