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    An Investigation of the Mediating role of Organizational Cynicism on the Relations between the Politics Perception and Organizational Commitment

    , M.Sc. Thesis Sharif University of Technology Taleghani, Mohammad (Author) ; Alavi, Babak (Supervisor) ; Banki, Sara (Supervisor)
    Abstract
    There is no consensus definition of cynicism in literature. In this research different definitions of cynicism have been investigated and two concept of organizational cynicism and trait cynicism have been taken into consideration. Organizational cynicism is a negative attitude that is prevalent in employees. In literature some antecedents and consequences of organizational cynicism have been suggested. It seems organizational cynicism can be investigated in a more complex relations. The focus of this research is on the mediating role of organizational cynicism on the likely relations between politics perception and organizational commitment. That is to say organizational cynicism can... 

    The Influence of Authentic Leadership on the Relationship between Transformational Leadership, and Feedback-seeking Behaviors

    , M.Sc. Thesis Sharif University of Technology Fadaee, Mohsen (Author) ; Alavi, Babak (Supervisor) ; Banki, Sara (Supervisor)
    Abstract
    Feedback-seeking behavior is the effort of employees to get feedback from the environment and around people about their performance. One of the research questions in this field is about the factors that increase this behavior in the staff. Transformational leadership as a leadership style, stimulates, and motivates followers to achieving desirable operational results. In addition, an important consequence of this style could be increasing the followers' capabilities. Transformational leaders are trying to empower their followers to build and empower them, which can provide a strong incentive for employees to move and grow, which may encourage them to have a better performance. One of... 

    Implementation and Development of a New Framework for Flexible Inter-PHY Functional Splitting in Cloud RAN Networks

    , M.Sc. Thesis Sharif University of Technology Basiri-Moghadam, Shahriar (Author) ; Hossein Khalaj, Babak (Supervisor)
    Abstract
    Thorough investigation of the Cloud-RAN (C-RAN) architecture has recently shown that CRAN can bring advanced cooperated and coordinated processing capabilities as well as the multiplexing gains toward future radio access networks. The baseband processing of each base station instance can now be flexibly split into smaller functional components, that can be placed either at remote radio units (RRUs) or baseband units (BBUs), depending on the available resources. In this project, we investigate recent implemented methods in C-RAN. also, we propose, develop and implement new architectural frameworks for C-RAN that can support both a flexible functional split and a new functional splitting known... 

    Identification of Self-Leadership Strategies of Social Entrepreneurs in Face of Challenges of their Career

    , M.Sc. Thesis Sharif University of Technology Nik, Farzaneh (Author) ; Alavi, Babak (Supervisor) ; Tasavori, Misagh (Supervisor)
    Abstract
    The present study seeks to focus on social entrepreneurs to address how these entrepreneurs continue to have sufficient motivation to overcome the challenges they face in the course of their careers and continue this path. This research has tried to use the concept of self-leadership - which keeps a person motivated to achieve his goals for which he has an inner motivation - to answer this question. So the main research question is how do social entrepreneurs use their leadership in the face of the challenges of their careers? To answer this question, this study used a qualitative research method with an exploratory approach and conducted semi-structured interviews with 14 social... 

    Simultaneous Coverage and Capacity Optimization and Load Balancing in Cellular Self-Organizing Networks

    , M.Sc. Thesis Sharif University of Technology Azarbahram, Amir Hossein (Author) ; Hossein Khalaj, Babak (Supervisor)
    Abstract
    Network dynamics, environmental changes, increasing number of users and their demand have made it necessary to continuously evaluate and optimize the network performance. Self organizing networks (SON) were introduced to add this capability to cellular networks. Among the SON functions, Coverage and Capacity Optimization (CCO) and Load Balancing (LB) are the most important ones. These two functions working collaboratively allows the operator to improve the network performance in terms of coverage and capacity while minimizing cell saturation and user dissatisfaction across the network. In this Thesis, a Two-Stage Optimization Approach has been proposed that enables the network to consider... 

    Modeling Two-Dimensional Face from DNA Using the Face Embedding Approach in Deep Learning

    , M.Sc. Thesis Sharif University of Technology Mirzaei, Mohammad Amin (Author) ; Hossein Khalaj, Babak (Supervisor)
    Abstract
    the purpose of this research is to construct the facial image of a person from corresponding DNA. In this problem, we have a set of DNAs and facial images and we want to find the relation between the DNA and the features of facial images.using this relation we can find the facial Image of a person using the DNA. for this purpose we should first extract the features of faces that have the most variation among the population. by studying the feature extraction methods in this field, we borrow the deep neural network method that is used in face recognition fields.we found significant relations between DNA and extracted features from this network. finally using this relation we can predict the... 

    Optimized Fabrication of Spinel Nanao Powder Mn1.5Co1.5O4 Through Sol-Gel Method Applicable to Solid Oxid Fuel Cell

    , M.Sc. Thesis Sharif University of Technology Hashemi, Tahereh (Author) ; Askari, Masoud (Supervisor)
    Abstract
    Nowadays, too much attention has been paid to Solid Oxide Fuel Cells (SOFC). One of the key components in SOFC is interconnect which plays an important role in SOFC performance. Interconnect can be either a metallic or ceramic layer that sits between each individual cell. The reduction in operating temperature of SOFC resulted in interests in using metallic interconnectors. However, the oxidation of these metallic materials is big challenge. Chromium (Cr), Nickel (Ni) and Iron (Fe) alloys have been employed to overcome this deficiency. However, these alloys bring another difficulty which is the presence of active elements such as Cr which reduces the performance of interconnects by forming... 

    Synthesis and Electrochemical Study of Endohedral Fullerenes Prepared by Arc Vaporizing Method

    , M.Sc. Thesis Sharif University of Technology Hashemi, Ali (Author) ; Ghanbari, Bahram (Supervisor)
    Abstract
    Fullerenes are molecular solid materials which are composed of 3D closed shell carbon-only structure. As soon as mass production of fullerenes was performed, the synthesis and characterization of endohedral fullerenes having at least one non-carbon element in the hollow fullerene cage, was started (in which about 30 atoms inserted in it so far). Furthermore, because of low efficiency and purity of these nano-particles, nowadays characterization of fullerenes is one of the most important research fields. In this project, we firstly optimized the fullerene production parameters in an arc discharge reactor to reach convenient efficiency. Then, the synthesis of endohedral fullerene by vaporizing... 

    Expert Finding in Bibliographic Network

    , M.Sc. Thesis Sharif University of Technology Hashemi, Hadi (Author) ; Beigy, Hamid (Supervisor)
    Abstract
    Expert finding in bibliographic networks has received increasing attention in recent years. This task concerns with finding relevant researchers for a given topic. In this thesis, we propose a model to determine authority of authors who have participated in the Communities. This model has a little improvement over community based baseline model. However, due to the low performance of community based models, the proposed authority based model cannot improve the document based baseline models either. Therefore, we try to improve document based models, instead of community based models and have proposed two other models which are based on authors’ topic dominance for expert finding. Document... 

    Model-Based Reasoning Based on Giere’s Explanation of Model

    , M.Sc. Thesis Sharif University of Technology Hashemi, Amin (Author) ; Heidari, Moghadam (Supervisor)
    Abstract
    In the present research, model-based reasoning is introduced and explained based on Giere’s explanation of model. In other word, this research could be regarded as a reconstruction of model in Giere’s books and papers due to prpose a clear explanation of model-based reasoning. In the second chapter, after the introduction, the concept of model in Giere’s distinguished book, “Explainnig Science: A Cognitive Approach” (1988) is introduced and analyzed. In the second chapter, however, the concept of model in Giere’s recent works is traced. “An agent-based account of model” and “focusing on functionality rather than ontology” could be explained as the two important differences between his... 

    Design and Hardware Implementation of Optical Character Recognition

    , M.Sc. Thesis Sharif University of Technology Dezfuli, Sina (Author) ; Hashemi, Matin (Supervisor)
    Abstract
    The objective of OCR systems is to retrieve machine-encoded text from a raster image. Despite the abundance of powerful OCR algorithms for English, there are not many for Farsi. Our proposed algorithm is comprised of pre-processing, line detection, sub-word detection and segmentation, feature extraction and classification. Furthermore, hardware implementation and acceleration of this system on a GPGPU is presented. This algorithm was tested on 5 fonts including Titr, Lotus,Yekan, Koodak and Nazanin and an average accuracy above 90% was achieved  

    A Scheme for Counterfeit Chip Detection Using Scan Chain

    , M.Sc. Thesis Sharif University of Technology Hashemi, Mona (Author) ; Hesabi, Shahin (Supervisor)
    Abstract
    With constant increase in the rate of VLSI circuits manufactured in sites separate from the designers and computer architects, global concern regarding the possibility of integration of malware by the manufacturing foundries has arisen. Particularly, one main issue that affects relability of the chips is modifications or additions with malicious intension, known as Harware Trojans, which are easily applicable during design and manufacturing phase of chip. This study intends to introduce a model based on the scan chain, a method is provided for intellectual property protection. Currently available IP protection solutions are usually limited to protect single FPGA configurations and require... 

    Empirical comparison of sliding friction and wear behaviors of gray and white cast iron

    , Article ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, ESDA2010, 12 July 2010 through 14 July 2010, Istanbul ; Volume 1 , 2010 , Pages 489-493 ; 9780791849156 (ISBN) Hashemi, M ; Ghajar, R ; Sharif University of Technology
    2010
    Abstract
    In this paper, sliding friction and wear behaviors of gray cast iron A35 and white cast iron manufactured by quenching from the same cast iron in water were studied and compared by employing pin-on-disk wear tests. Microstructure of the worn surfaces before and after the wear tests were investigated by optical microscope observations. These images show that flakes separated from the surface in gray cast iron due to delamination process, while in white cast iron, the separation of materials from its surface is in the form of powder. In addition, the gray cast iron had higher graphite volume fraction with Type-A graphite flake morphology. The results show that white cast iron has less rate of... 

    Investigation of the small-scale effects on the three-dimensional flexural vibration characteristics of a basic model for micro-engines

    , Article Acta Mechanica ; Volume 226, Issue 9 , September , 2015 , Pages 3085-3096 ; 00015970 (ISSN) Hashemi, M ; Asghari, M ; Sharif University of Technology
    Springer-Verlag Wien  2015
    Abstract
    The coupled three-dimensional flexural vibrations of a micro-rotating shaft–disk system, as a basic model for micro-engines, are investigated in this paper by considering small-scale effects utilizing the modified couple stress theory. Governing equations of motion are derived by the use of Hamilton’s principle. Then, implementing the Galerkin approach, an infinite set of ordinary differential equations is obtained for the system. With truncated two-term equations, expressions for the first two natural frequencies are written, and for the two corresponding modes, the maximum rotational speed up to which the system will be stable is analytically determined. Parametric studies on the results... 

    Analytical study of three-dimensional flexural vibration of micro-rotating shafts with eccentricity utilizing the strain gradient theory

    , Article Meccanica ; Volume 51, Issue 6 , 2016 , Pages 1435-1444 ; 00256455 (ISSN) Hashemi, M ; Asghari, M ; Sharif University of Technology
    Springer Netherlands  2016
    Abstract
    In this work, some vibrational response parameters of strain gradient based micro-spinning Rayleigh beams with mass eccentricity distribution are investigated within infinitesimal deformation conditions. Governing equations of motion are derived utilizing the Hamilton’s principle. The gyroscopic effects and rotary inertia are both included in the formulation. By applying the Galerkin method, analytical expressions for natural frequencies of the micro beam in forward and backward whirl motions are obtained. In addition, an expression for the vibrational amplitude of the micro-beam due to mass eccentricity distribution is determined. Some numerical results are presented to study the effect of... 

    Vibration Analysis of Micro-Engine Rotor on the Basis of Non-classical Theories of Continuum Mechanics

    , Ph.D. Dissertation Sharif University of Technology Hashemi, Mehdi (Author) ; Asghari, Mohsen (Supervisor)
    Abstract
    Micro-rotating machinery with compact energy sources and high power density has been developed in the recent decade to run portable electronic devices. To achieve efficiency targets, these miniaturized turbo-machinery must spin at elevated rotational speeds which sometimes can reach up to one million revolutions per minute. At this relatively high spinning rate, the rotordynamic behavior of these systems plays an important role in the stage of design. On the other hand, the classical continuum theory has been proven not to be able to appropriately predict the mechanical behavior of the small-scale structures. To overcome overall mentioned weakness, in this thesis the rotor of micro-engines... 

    Size-dependent vibrational behavior of a Jeffcott model for micro-rotor systems

    , Article Journal of Mechanical Science and Technology ; Volume 30, Issue 1 , 2016 , Pages 35-41 ; 1738494X (ISSN) Hashemi, M ; Asghari, M ; Sharif University of Technology
    Korean Society of Mechanical Engineers  2016
    Abstract
    In this study, several analytical expressions are obtained for the vibrational characteristics of a Jeffcott model for micro-rotor systems based on the strain gradient theory to investigate the small-scale effects on the model. The Jeffcott model consists of a massless microrotating shaft and a disk as a rotor with eccentricity. The disk is mounted on the middle of the shaft. Two second-order differential equations associated with the oscillating motion of the rotor in the plane perpendicular to the longitudinal axis are presented and transformed into a complex form. The stiffness of the system is determined by obtaining the deflection of a strain-gradient-based nonrotating microbeam... 

    Efficient Implementation of Compressed Deep Convolutional Neural Networks

    , M.Sc. Thesis Sharif University of Technology Afshar, Mohammad (Author) ; Hashemi, Matin (Supervisor)
    Abstract
    Many mobile applications running on smartphones, wearable devices, tiny autonomous robots and IoT devices would potentially benefit from the accuracy and scalability of deep CNN-based machine learning algorithms. However,performance and energy consumption limitations make the execution of such computationally intensive algorithms on embedded mobile devices prohibitive.We present a GPU-accelerated engine, dubbed mCNN, for execution of trained deep CNNs on mobile platforms. The proposed solution takes the trained model as input and automatically optimizes its parallel implementation on the target mobile platform for efficient use of hardware resources such as mobile GPU threads and SIMD units.... 

    On the size-dependent flexural vibration characteristics of unbalanced couple stress-based micro-spinning beams

    , Article Mechanics Based Design of Structures and Machines ; Volume 45, Issue 1 , 2017 , Pages 1-11 ; 15397734 (ISSN) Hashemi, M ; Asghari, M ; Sharif University of Technology
    2017
    Abstract
    On the basis of the modified couple stress theory, some analytical results are obtained for vibrational parameters of micro-spinning Rayleigh beams with an axial mass-eccentricity distribution. The modified couple stress theory is a nonclassical continuum theory capable to capture the size effects in small-scale structures. After writing the governing equations of motion, they are transformed to the complex form. Then by utilizing the Galerkin method, analytical expressions for natural frequencies of the micro-spinning beam in forward and backward whirl motions are obtained. Critical speeds are also analytically presented in the two whirl motions for different modes. Moreover, the... 

    Design and Efficient Hardware Implementation of Spiking Neural Networks on FPGA

    , M.Sc. Thesis Sharif University of Technology Amirshahi, Alireza (Author) ; Hashemi, Matin (Supervisor)
    Abstract
    Spiking Neural Networks(SNN) are networks which are consisted of layers of neurons, like other typical artificial neural networks. The main difference between SNN and other neural networks is the type of data transportation among neurons which is done by spikes. Spiking neural networks and their models are considered as the nearest networks and neurons to animals’ nervous systems. In aspects of hardware implementation, the type of data transportation in SNN causes them to be ultra-low power. So, implementation of these networks on chips like FPGA and also usage of SNN in applications with high processing load have startling germination, recently. In this work, we have tried to propose some...