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    The Simultaneous Berth and Quay Crane Scheduling

    , M.Sc. Thesis Sharif University of Technology Zokaei Nikoo, Maryam (Author) ; Salmasi, Naser (Supervisor)
    This study addresses the simultaneous berth and quay crane (QC) scheduling problem in a container terminal. The berths are considered as a continuous area and the vessels arrive dynamically. QCs are allowed to move to other vessels before completing the process on an assigned vessel.The objective function is determined based on the practical applications of the problem. It deals with minimization of sum of the completion time of vessels. In this research, a mathematical model has been developed for the research problem. According to NP-hardness of the research problem, two meta heuristic algorithms based on Tabu Search are proposed. To solve the problem, these methods have two layers with... 

    Combination of Linear MPC and Differential Game Theory for Optimal Cooperative Terminal Guidance Law with HIL Simulation

    , M.Sc. Thesis Sharif University of Technology Akbari, Mohammad Sadegh (Author) ; Nobahari, Hadi (Supervisor)
    In this research, a cooperative terminal guidance algorithm has been derived for simultaneous multi-interceptor collision with a target. This algorithm is obtained using the combination of model predictive control method and differential game theory. One of the features of this method is the calculation of the optimal guidance command in the form of an explicit relationship. Another feature of this method is its resistance to disturbances due to the use of differential game theory. The first innovation of this research is the use of this hybrid method to create a guidance algorithm, even in the non-cooperative guidance problem. The next innovation is in creating a cooperative terminal... 

    A Systematic Model to Determine Minimum Separation for VToL in Terminal Phase

    , M.Sc. Thesis Sharif University of Technology Adeli Koudehi, Ali (Author) ; Malaek, Mohammad Bagher (Supervisor)
    For the VTOL aircraft mission profiles, terminal phases are considered the most crucial and convoluted due to the interrelated aspects involved in transition from level flight into vertical motion. Flight safety is the trivial, yet essential requisite that should be satisfied during all flight phases. This paper aims to present a comprehensive model for determining a safe distance for urban VTOL air taxies during the landing phase through predicting possible conflictions and reducing this possibility by performing a conflict resolution maneuver while maintaining the flight safety requirements.The safe distance during landing is calculated based on a Monte-Carlo simulation which employs the... 

    Investigation of E-Vtol Performance Parameters on the Characteristics of Civil Air-Taxi Network

    , M.Sc. Thesis Sharif University of Technology Kiani, Arash (Author) ; Malaek, Mohammad Bagher (Supervisor)
    Nowadays more than half of the world’s population lived in urban areas. That proportion is set to rise to 67% by 2050. This will cause urban mobility with serious problems. The concept of Urban Air Mobility (UAM) is proposed to avoid the problem to become a catastrophy. Due to environmental issues and also high operating costs, using copters as an air-taxi was not justifiable. As the technology in e-VTOL flourished, the desire of using of these vehicles in such a transportation system was increased. In this paper, besides previous investigations, the e-VTOL’s performance parameters’ influence on the characteristic of a civil air-taxi network is under investigation. In addition, this paper... 

    Study, Analysis & Optimizing The Process Of Approval, Design & Implementation Of Projects In The Iranian Oil Terminal Company(IOTC)

    , M.Sc. Thesis Sharif University of Technology Moosavi, Saeed (Author) ; Mostafavi, Mostafa (Supervisor)
    Since the Iranian oil terminals company(I.O.T.C.) has been the main and strategic gateway of exporting petroleum in the country and plays an important role in the optimum continuity of national, regional and international energy supply chain and also conducting the needed projects whit a desirable quality and minimum time and cost has a prominent influence on steady continuity of manufacturing, importing and exporting of petroleum and gas production. The main purpose of doing this thesis is diagnosing the process of approval, design and implementation of projects in the I.O.T.C., Thus, whit regarding to the modern needs of implementing projects and the necessity of reviewing the structure... 

    Gaining Competitive Advantage through Marketing Strategies in Container Terminal: A Case Study on Shahid Rajaee Port in Iran

    , M.Sc. Thesis Sharif University of Technology Cheraghi, Hossein (Author) ; Miremadi, Ali Reza (Supervisor)
    The competitiveness of a port convinced shipping lines and shippers with a significant basis in selecting a port. Port authorities and port operators can make use of the competitive advantage as a parameter for counter measures by grasping the advantages and disadvantages of the ports and be a prime factor of opportunities and threats of the ports. Ports have a significant role in today’s networked business environment. They are being regarded as hubs that are part of various logistic systems. The very essence of a seaport is to link maritime networks and land network. These networks for the port are means of analyzing its competitiveness. A port overall competitiveness is determined by it’s... 

    Terminal Flight Path Optimization Pattern for High Traffic Airports for Noise

    , M.Sc. Thesis Sharif University of Technology Mostaghimi Rezazade, Saeed (Author) ; Malaek, Mohammad Bagher (Supervisor)
    The only problem in aviation and airport development is the noise print on population groups surrounding airports due to its high frequency it is so annoying for human ear. In order to overcome this problem technology has reached its edge and the only alternative is to deviate terminal flight path.In this thesis I tried find a pattern for optimizing terminal flight path considering a Boeing 737-800 taking off from Mehrabad airport’s runway 29. To do this we were in need of a huge database of airplane low speed model, geographic information and population knowledge.The common approaches used by FAA and other international organizations for modeling low speed flight were used. The influence of... 

    Evaluation of Exerted Drag Force on Alkane Saturated Air Bubbles in Aqueous Solutions by Experimental Studies

    , M.Sc. Thesis Sharif University of Technology Rajabzadeh Dezfuli, Mehdi (Author) ; Bastani, Dariush (Supervisor) ; Lotfi, Marzieh (Supervisor)
    Interfacial phenomena and properties of interphase surfaces in dynamic mode play an important role in industrial processes that include gas-liquid and liquid-liquid multiphase flows. As well as, interface knowledge leads to better understanding of natural and fundamental phenomena. The present study has been performed for understanding about dynamic behavior of interphase surfaces in the presence of nanoparticles and hexane vapor in gas-liquid dispersion systems. In this research, rising bubble method has been used as one of the most conventional techniques. Accordingly, aqueous solutions of nanosilica were prepared in concentrations of 50, 100, 200, 400 and 1200 ppm as continuous phase... 

    Introducing a Simulation-Based Model to Improve the Design and Layout of Workstations Inside Airport Terminals in Iran

    , M.Sc. Thesis Sharif University of Technology Amini Esfidvajani, Amin Mohammad (Author) ; Alvanchi, Amin (Supervisor)
    The airport terminal is difficult to plan and design due to the different components and the intricate complexity of its parts. At the airport terminal, we face a queue system which simulation is always a good way to analyze. In addition, computer simulation using modern softwares with the capability to model different types of systems, including the airport terminal, while being less realistic than analytical models, is less costly than operational Exercise.In this study, a supportive approach for better and specific management of Iranian airport terminal buildings with discrete-event simulation is proposed, considering the need for managing the airport terminals building in the country and... 

    Well-conditioned sensor placement for range-only localization

    , Article 2011 4th IFIP International Conference on New Technologies, Mobility and Security, NTMS 2011 - Proceedings, 7 February 2011 through 10 February 2011 ; February , 2011 , Page(s): 1 - 5 ; ISSN : 21574952 ; 9781424487042 (ISBN) Shadi, K ; Dehghani, H. L ; Gholampour, I ; Sharif University of Technology
    This paper addresses the optimality of Network topology for localization purposes when measurements are range-only. Localization procedures based on TOA and TDOA range measurements are considered in this paper. As of now, the optimal placement of fixed terminals to locate mobile terminals has been studied based on Cramer-Rao Lower Bound (CRLB). CRLB is a universal bound on the variance of a general unbiased estimator and therefore is not dependent to the estimator and methods of localization. Here we introduce another algorithm dependent criterion, based on perturbation theory of linear equations. Different optimal topologies are presented using the new criterion. These optimal topologies,... 

    Using RLS adaptive algorithm for packet loss replacement in VOIP

    , Article Proceedings of the 2011 International Conference on Image Processing, Computer Vision, and Pattern Recognition, IPCV 2011, 18 July 2011 through 21 July 2011 ; Volume 2 , July , 2011 , Pages 753-756 ; 9781601321916 (ISBN) Miralavi, S.R ; Ghorshi, S ; Mortazavi, M ; Sharif University of Technology
    In this paper, a low order recursive linear prediction method and recursive least square as an adaptive filter (LP-RLS) are introduced to predict the speech and the excitation signals. In real-time packet-based communication systems, one major problem is misrouted or delayed packets which results in degraded perceived voice quality. If packets are not available on time, the packet is known as lost packet. The easiest task of a network terminal receiver is to replace silence for the duration of lost speech segments. In a high quality communication system, to avoid quality reduction due to packet loss, a suitable method and/or algorithm is needed to replace the missing segments of speech. The... 

    Use of a novel initiator for synthesis of amino-end functionalized polystyrene (NH 2-PS) by atom transfer radical polymerization

    , Article Journal of Polymer Research ; Volume 19, Issue 1 , January , 2012 ; 10229760 (ISSN) Pourjavadi, A ; Seidi, F ; Jahromi, P. E ; Salimi, H ; Roshan, S ; Najafi, A ; Bruns, N ; Sharif University of Technology
    Here we report a versatile new method for endfunctionalizing polystyrene. In order to produce polystyrene with an amino end group, 2-(3-bromo-3- phenylpropyl) isoindoline-1,3-dione was synthesized and used as a novel initiator for ATRP. After ATRP polymerization, tri-n-butyltin hydride ((n-Bu) 3SnH) reductively replace existing halogens on polymer chains by hydrogen. Finally, the phthaloyl groups on polymer backbone were cleaved by treatment with hydrazine yielding amino terminated polystyrene. A polymer with M n≈10,350 and M w/M n01.17 was obtained. Therefore, this method allows the preparation of amino end functionalized polystyrene of narrow polydispersity with complete degree of... 

    TSRN: A tabu search-based routing protocol for named data networking

    , Article Wireless Personal Communications ; Volume 101, Issue 3 , 2018 , Pages 1411-1428 ; 09296212 (ISSN) Shariat, Z ; Movaghar, A ; Hosseinzadeh, M ; Sharif University of Technology
    Springer New York LLC  2018
    Information-centric network (ICN) has become a basic research topic with regard to the future architecture of the Internet. Storage and routing data is an important feature of ICN, as it improves network performance and content distribution. One of the challenges in this type of network is the routing problem. The objective of this paper is to propose a routing algorithm in the named data network. Owing to the impressive results presented by the enhanced heuristic methods, tabu search has been selected to develop the proposed algorithm. This work has been carried out in five major steps, Creating the initial solution, The mechanisms of generating a neighborhood, Evaluating the neighbor... 

    Thrust termination dynamics of solid propellant rocket motors

    , Article Journal of Propulsion and Power ; Volume 23, Issue 5 , 2007 , Pages 1141-1142 ; 07484658 (ISSN) Tahsini, A. M ; Farshchi, M ; Sharif University of Technology
    American Institute of Aeronautics and Astronautics Inc  2007
    Thrust termination dynamics of a solid propellant rocket motor that is crucial to the performance of the rocket has been analyzed. Active thrust termination or reversing of a separating motor facilitate the staging process and enhance the performance of a multistage rocket. This can be achieved by opening a secondary nozzle located on the motor head and causing rapid depressurization of the motor chamber. The strong dependence of the solid propellant burning rate on the chamber pressure causes a transient nonlinear behavior that can result in premature dynamic extinguishments of the motor. It was confirmed that there is a maximum achievable level of equilibrium reverse thrust due to... 

    Throughput analysis of a cognitive multi-hop IEEE 802.11-based WLAN overlaid on a cellular network

    , Article 2011 International Conference on Software, Telecommunications and Computer Networks, SoftCOM 2011, 15 September 2011 through 17 September 2011, Split, Hvar, Dubrovnik ; 2011 , Pages 307-311 ; 9789532900262 (ISBN) Soleimani, H ; Ashtiani, F ; Sharif University of Technology
    In this paper, we focus on a cognitive network scenario, comprised of a multi-hop IEEE 802.11-based WLAN overlaid on a cellular network. In this scenario, the wireless nodes in a WLAN, i.e., cognitive nodes, use the downlink frequency channels of the cellular network opportunistically, such that at each packet transmission all idle channels have been exploited. In order to evaluate the capability of the considered cognitive network scenario, we propose an open queueing network model such that different packet transmission phases are mapped onto different queueing nodes. We also map different types of collisions, i.e., collision on control signals as well as collision on data transmission due... 

    ST-CAC: a low-cost crosstalk avoidance coding mechanism based on three-valued numerical system

    , Article Journal of Supercomputing ; Volume 77, Issue 7 , 2021 , Pages 6692-6713 ; 09208542 (ISSN) Shirmohammadi, Z ; Khorami, A ; Omana, M. E ; Sharif University of Technology
    Springer  2021
    Appearances of specific transition patterns during data transfer in bus lines of modern high-performance computing systems, such as communicating structures of accelerators for deep convolutional neural networks, commercial Network on Chips, and memories, can lead to crosstalk faults. With the shrinkage of technology size, crosstalk faults occurrence boosts and leads to degradation of reliability and performance, as well as the increasing power consumption of lines. One effective way to alleviate crosstalk faults is to avoid the appearance of these specific transition patterns by using numerical-based crosstalk avoidance codes (CACs). However, a serious problem with numerical-based CACs is... 

    Spike phase synchronization in delayed-coupled neural networks: Uniform vs. non-uniform transmission delay

    , Article Chaos ; Volume 23, Issue 1 , 2013 ; 10541500 (ISSN) Jalili, M ; Sharif University of Technology
    In this paper, we investigated phase synchronization in delayed dynamical networks. Non-identical spiking Hindmarsh-Rose neurons were considered as individual dynamical systems and coupled through a number of network structures such as scale-free, Erdos-Rényi, and modular. The individual neurons were coupled through excitatory chemical synapses with uniform or distributed time delays. The profile of spike phase synchrony was different when the delay was uniform across the edges as compared to the case when it was distributed, i.e., different delays for the edges. When an identical transmission delay was considered, a quasi-periodic pattern was observed in the spike phase synchrony. There... 

    Solving bus terminal location problems using evolutionary algorithms

    , Article Applied Soft Computing Journal ; Volume 11, Issue 1 , 2011 , Pages 991-999 ; 15684946 (ISSN) Ghanbari, R ; Mahdavi Amiri, N ; Sharif University of Technology
    Bus terminal assignment with the objective of maximizing public transportation service is known as bus terminal location problem (BTLP). We formulate the BTLP, a problem of concern in transportation industry, as a p-uncapacitated facility location problem (p-UFLP) with distance constraint. The p-UFLP being NP-hard (Krarup and Pruzan, 1990), we propose evolutionary algorithms for its solution. According to the No Free Lunch theorem and the good efficiency of the distinctive preserve recombination (DPX) operator, we design a new recombination operator for solving a BTLP by new evolutionary and memetic algorithms namely, genetic local search algorithms (GLS). We also define the potential... 

    Reliability evaluation of an HVDC transmission system tapped by a VSC station

    , Article IEEE Transactions on Power Delivery ; Vol. 25, issue. 3 , 2010 , p. 1962-1970 ; ISSN: 8858977 Zadkhast, S ; Fotuhi-Firuzabad, M ; Aminifar, F ; Billinton, R ; Faried, S. O ; Edris, A. -A ; Sharif University of Technology
    Reliability evaluation of multiterminal HVDC systems has received very little attention in the past. This paper presents reliability modeling and analysis of an HVDC transmission system incorporating a voltage-sourced converter (VSC) tapping station. The use of VSC tapping stations enables the supply of power along the route to areas with comparatively little consumption. In this paper, a comprehensive detailed reliability model is developed and then converted to a manageable and computationally efficient model. Using this equivalent reliability model, various reliability indices are calculated at the load point of the system and the impacts of the VSC tapping station on these indices are... 

    Reliability evaluation of an HVDC transmission system tapped by a VSC station

    , Article IEEE Transactions on Power Delivery ; Volume 25, Issue 3 , April , 2010 , Pages 1962-1970 ; 08858977 (ISSN) Zadkhast, S ; Fotuhi Firuzabad, M ; Aminifar, F ; Billinton, R ; Faried, S. O ; Edris, A. A ; Sharif University of Technology
    Reliability evaluation of multiterminal HVDC systems has received very little attention in the past. This paper presents reliability modeling and analysis of an HVDC transmission system incorporating a voltage-sourced converter (VSC) tapping station. The use of VSC tapping stations enables the supply of power along the route to areas with comparatively little consumption. In this paper, a comprehensive detailed reliability model is developed and then converted to a manageable and computationally efficient model. Using this equivalent reliability model, various reliability indices are calculated at the load point of the system and the impacts of the VSC tapping station on these indices are...