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    Aerodynamic Design of 100 kW Transonic Ducted Fan

    , M.Sc. Thesis Sharif University of Technology Shayan Fakhr, Atefeh (Author) ; Ghorbanian, Kaveh (Supervisor)
    Abstract
    The purpose of this research is the aerodynamic design of a 100 kW transonic ducted fan. Today, the aviation industry is moving towards the design of electric driven aircraft propulsion. Transonic ducted fans are one of the viable options that have been used in medium and heavy aircrafts due to their high specific power. In this research, the meanline model has been used for the initial design. By applying the design constraints, design limitations, design and functional parameters, the initial design point is found and then a sensitivity analysis is performed with respect to the effective design parameters to obtain the optimal design point. For the initial design of the transonic ducted... 

    Techno-Economic Comparison of Different Gas Turbine Inlet Cooling Techniques

    , M.Sc. Thesis Sharif University of Technology Shayan, Mahdi (Author) ; Hakkaki Fard, Ali (Supervisor)
    Abstract
    Inlet air cooling is a simple and economical method to increase the power output of gas turbines. High-pressure fogging systems and mechanical chillers are two common methods. High water consumption, damage to compressor blades by water droplets, and inefficiency in humid climates are disadvantages of high-pressure fogging systems. Mechanical chillers have high electricity consumption and initial costs. In this research, an earth-to-air heat exchanger (EAHE) is introduced as a new method for inlet air cooling of gas turbines and is technically and economically compared with the two common methods in the long term in the climate of Tehran city. Temperature distribution in the ground is... 

    Community structure and information cascade in signed networks

    , Article New Generation Computing ; Vol. 32, issue. 3-4 , August , 2014 , p. 257-269 Shafaei, M ; Jalili, M ; Sharif University of Technology
    2014
    Abstract
    In this paper, we study information cascade in networks with positive and negative edges. The cascade depth is correlated with community structure of signed networks where communities are defined such that positive inter-community and negative intra-community links are minimized. The cascade is initialized from a number of nodes that are selected randomly. Finally, the number of nodes that have participated in the cascade is interpreted as cascade depth; the more the number of such nodes, the more the depth of the cascade. We investigate influence of community structure (i.e.; percentage of inter-community positive and intra-community negative links) on the cascade depth. We find significant... 

    Modeling Information Cascade in Social Network with Positive and Negative

    , M.Sc. Thesis Sharif University of Technology Shafaei, Mahsa (Author) ; Jalili, Mahdi (Supervisor)
    Abstract
    Information cascade or affection in a broad social network is introduced as a dynamic epidemic phenomenon in the society. As people notify a new innovation, technology, or hobby, they try to share it with their friends, colleges or neighbors. Till now most of the cascade models are presented for unsigned network, in which all links have the same sign (such as friends and trusted networks). In these networks cascade is independent of the edge sign. But in reality signed networks are as common as simple networks. Thus, in this thesis, we study information cascade in networks with positive and negative edges. We link the cascade size to community structure of signed networks; communities are... 

    Evaluation of Lump Sum Contracts in the Organization for Development, Renovation and Equipping Schools

    , M.Sc. Thesis Sharif University of Technology Shafaei, Mohsen (Author) ; Mofid, Masoud (Supervisor)
    Abstract
    The construction industry is one of the most important economic sectors, which shares a major part of Gross Domestic Product (GDP) and employment. In Iran many development projects are designed and implemented annually which billions of Rials are due as a result of construction and operation for executive bodies. The Organization for Development, Renovation and Equipping Schools (ODRES) as the executive branch of the Ministry of Education, is one of the largest construction bodies which undertakes construction of hundreds of educational, cultural and athletic projects annually. Given that the project delivery methods and the need to choose the correct method of contract payments exerts great... 

    Crosstalk Fault Modeling and Mitigation in System-on-Chips

    , M.Sc. Thesis Sharif University of Technology Shafaei Moghaddam, Mansour (Author) ; Miremadi, Ghassem (Supervisor)
    Abstract
    Use of nano-scale VLSI technologies in the fabrication of System-on-Chips (SoCs) makes reliability as one of the major issues in the design and implementation of these products. SoCs are susceptible to several fault sources such as crosstalks, cosmic particle strikes, electromagnetic interferences, and power supply disturbances. Among the mentioned fault sources, crosstalks have the major contribution in threatening the reliability of SoCs. This thesis addresses the modeling and mitigation of crosstalk faults. In this regard, two analytical models and three crosstalk reduction methods have been introduced. The proposed analytical models, which have been introduced in the fourth chapter of... 

    Numeral-based crosstalk avoidance coding to reliable NoC design

    , Article Proceedings - 2011 14th Euromicro Conference on Digital System Design: Architectures, Methods and Tools, DSD 2011 ; 2011 , Pages 55-62 ; 9780769544946 (ISBN) Shafaei, M ; Patooghy, A ; Miremadi, S. G ; Sharif University of Technology
    2011
    Abstract
    This paper proposes a Numeral-Based Crosstalk Avoidance Coding (NB-CAC) to protect communication channels of Network-on-Chips (NoCs) against crosstalk faults. The NB-CAC scheme produces codewords without bit patterns '101' and '010' to eliminate harmful transition patterns from NoC channels. This is done by the use of a new numeral system proposed in the paper. Using the proposed numeral system, the NB-CAC scheme 1) can be utilized in NoC channels with any arbitrary width, and 2) can be implemented with low area, power, and timing overheads. VHDL and SPICE simulations have been carried out for a wide range of channel widths to evaluate delay, area, and power consumption of the NB-CAC codecs.... 

    Crosstalk modeling to predict channel delay in Network-on-Chips

    , Article Proceedings - IEEE International Conference on Computer Design: VLSI in Computers and Processors, 3 October 2010 through 6 October 2010 ; October , 2010 , Pages 396-401 ; 10636404 (ISSN) ; 9781424489350 (ISBN) Patooghy, A ; Miremadi, S. G ; Shafaei, M ; Sharif University of Technology
    2010
    Abstract
    Communication channels in Network-on-Chips (NoCs) are highly susceptible to crosstalk faults due to the use of nano-scale VLSI technologies in the fabrication of NoCs. Crosstalk faults cause variable timing delay in NoC channels based on the patterns of transitions appearing on the channels. This paper proposes an analytical model to estimate the timing delay of an NoC channel in the presence of crosstalk faults. The model calculates expected number of 4C, 3C, 2C, and 1C transition patterns to predict delay of a K-bit communication channel. The model is applicable for both non-protected channels and channels which are protected by crosstalk mitigation methods. Spice simulations are done in a... 

    Design and Optimization of Carbon Capture System from Exhaust Gases in the Process Industries

    , M.Sc. Thesis Sharif University of Technology Farshi Taghavi, Mahdis (Author) ; Rashtchian, Davood (Supervisor) ; Seif, Shayan (Co-Supervisor)
    Abstract
    Carbon dioxide is one of the main geenhouse gases emitted from factories as well as transportation vehicles that adversely affect the atmosphere and cause global warming. Among the proposed solutions to reduce carbon dioxide in the atmosphere, carbon dioxide separation would be the most viable medium-term approach. However, the high cost of carbon dioxide separation prevents the development of carbon dioxide absorption technologies. Therefore, it seems that integrating separation and production processes is the most efficient way to save energy and reduce carbon emissions. This method decrease a high proportion of the energy consumption in upstream operations (carbon dioxide removal,... 

    Optimization, Fabrication and Utilization of a New Tendon Actuated Manipulator with Lockable Joints

    , M.Sc. Thesis Sharif University of Technology Shafaei, Mohsen (Author) ; Alasty, Aria (Supervisor) ; Salarieh, Hassan (Supervisor)
    Abstract
    Serpentine manipulators are a kind of hybrid manipulators that have a large number of joints and degrees of freedom. Due to their high flexibility, they have a great potential to work in constrained environment that filled with obstacles. One of the main problems of this type of manipulators is high weight and controlling difficulties. Many researches have been done to achieve lighter weight and simplify control methods of hyper-redundant manipulator. One way is putting the actuators in the base of the manipulator and transferring the actuator forces by cable. In this way, one cable and one actuator per controllable DOF is needed. Therefore, the weight and cost will increase dramatically... 

    Aging Based Cache Policy for The Network of Caches

    , M.Sc. Thesis Sharif University of Technology Shafaei, Shayan (Author) ; Rezazad, Mostafa (Supervisor) ; Ghahramani, Amirali (Co-Supervisor)
    Abstract
    The basis of the current IP-based networking architecture is on addressing locations (IP addresses). This way of locating and searching content does not meet the existing applications’ demands for generating and consuming larger data. In order to confront this problem, Named Data Networking (NDN) has been proposed that allocates names to data instead of the location. This fundamental change improves the functionality of the network in terms of various aspects such as smoother mobile routing, higher security, intrinsic multicast, broadcast system, and enables caching at the network level. As data directly receives an address in NDN, it can reside anywhere in the network. Furthermore, content... 

    Vehicle Routing Problems with Mobile and Stochastic Customer Locations (VRP-MSCL)

    , Ph.D. Dissertation Sharif University of Technology Shafaei, Abolfazl (Author) ; Akbari Jokar, Mohammad Reza (Supervisor) ; Rafiee, Majid (Supervisor) ; Hemmati, Ahmad (Co-Supervisor)
    Abstract
    In classical vehicle routing problems, a fixed and specific location is considered for each customer, which in many cases does not reflect reality. Many customers change their locations when distribution is carried out, and in some cases, it is challenging to predetermine their locations. This thesis proposes and develops the Vehicle Routing Problem with Mobile and Stochastic Customer Locations (VRP-MSCL), a subproblem of last-mile delivery. The concept of mobile and stochastic customer refers to a type of customer who is constantly moving, lacks a fixed location, and cannot be identified in advance; however, forecasting customers’ locations in advance is possible. This concept introduces a... 

    PH-Sensitive stimulus-responsive nanocarriers for targeted delivery of therapeutic agents

    , Article Wiley Interdisciplinary Reviews: Nanomedicine and Nanobiotechnology ; Volume 8, Issue 5 , 2016 , Pages 696-716 ; 19395116 (ISSN) Karimi, M ; Eslami, M ; Sahandi Zangabad, P ; Mirab, F ; Farajisafiloo, N ; Shafaei, Z ; Ghosh, D ; Bozorgomid, M ; Dashkhaneh, F ; Hamblin, M. R ; Sharif University of Technology
    Wiley-Blackwell  2016
    Abstract
    In recent years miscellaneous smart micro/nanosystems that respond to various exogenous/endogenous stimuli including temperature, magnetic/electric field, mechanical force, ultrasound/light irradiation, redox potentials, and biomolecule concentration have been developed for targeted delivery and release of encapsulated therapeutic agents such as drugs, genes, proteins, and metal ions specifically at their required site of action. Owing to physiological differences between malignant and normal cells, or between tumors and normal tissues, pH-sensitive nanosystems represent promising smart delivery vehicles for transport and delivery of anticancer agents. Furthermore, pH-sensitive systems... 

    Smart micro/nanoparticles in stimulus-responsive drug/gene delivery systems

    , Article Chemical Society Reviews ; Volume 45, Issue 5 , 2016 , Pages 1457-1501 ; 03060012 (ISSN) Karimi, M ; Ghasemi, A ; Sahandi Zangabad, P ; Rahighi, R ; Moosavi Basri, S. M ; Mirshekari, H ; Amiri, M ; Shafaei Pishabad, Z ; Aslani, A ; Bozorgomid, M ; Ghosh, D ; Beyzavi, A ; Vaseghi, A ; Aref, A. R ; Haghani, L ; Bahrami, S ; Hamblin, M. R ; Sharif University of Technology
    Royal Society of Chemistry  2016
    Abstract
    New achievements in the realm of nanoscience and innovative techniques of nanomedicine have moved micro/nanoparticles (MNPs) to the point of becoming actually useful for practical applications in the near future. Various differences between the extracellular and intracellular environments of cancerous and normal cells and the particular characteristics of tumors such as physicochemical properties, neovasculature, elasticity, surface electrical charge, and pH have motivated the design and fabrication of inventive "smart" MNPs for stimulus-responsive controlled drug release. These novel MNPs can be tailored to be responsive to pH variations, redox potential, enzymatic activation, thermal...