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    Role of Affective Commitment in the Relationship between Ostracism and Turnover Intention

    , M.Sc. Thesis Sharif University of Technology Zeytonli, Asiyeh (Author) ; Banki, Sara (Supervisor)
    Abstract
    A lot of researchers have suggested that ostracism as a disruptive behavior, has been widespread among organizations and a lot of researches has been studied its consequences in recent years.This research studies ostracism’s consequences and proposes a theoretical model of organizational ostracism with affective commitment, intention to turnover and organizational dependability as one of affective commitment’s antecedents. This study has been done on 231 employees of three medium knowledge-based organizations to identify the effects of ostracism on employee’s turnover behavior. Results show that ostracism, due to its impact on the affective commitment of ostracized peoples, reduces this type... 

    Simulation of SO2 absorption in a venturi scrubber

    , Article Chemical Engineering Communications ; Volume 197, Issue 7 , Feb , 2010 , Pages 934-952 ; 00986445 (ISSN) Taheri, M ; Mohebbi, A ; Taheri, A ; Sharif University of Technology
    2010
    Abstract
    In this study, a three-dimensional mathematical model, based on a nonuniform droplet concentration distribution, has been developed to simulate gas absorption in a venturi scrubber. The mass transfer process was illustrated by assuming the liquid phase as a combination of droplets and film. The flow, just as the annular two-phase flow, includes a flow of liquid film layer on the walls and a flow of gas and liquid drops in the core. Peclet number was determined using experimental data reported by Viswanathan et al. (1984) for distribution of droplets across the cross section of the scrubber. The mathematical model for gas absorption was justified by comparing the theoretical predictions with... 

    The effect of prestrain temperature on kinetics of static recrystallization, microstructure evolution, and mechanical properties of low carbon steel

    , Article Journal of Materials Engineering and Performance ; Volume 27, Issue 5 , 2018 , Pages 2049-2059 ; 10599495 (ISSN) Akbari, E ; Karimi Taheri, K ; Karimi Taheri, A ; Sharif University of Technology
    Springer New York LLC  2018
    Abstract
    In this research, the samples of a low carbon steel sheet were rolled up to a thickness prestrain of 67% at three different temperatures consisted of room, blue brittleness, and subzero temperature. Microhardness, SEM, and tensile tests were carried out to evaluate the static recrystallization kinetics defined by the Avrami equation, microstructural evolution, and mechanical properties. It was found that the Avrami exponent is altered with change in prestrain temperature and it achieves the value of 1 to 1. 5. Moreover, it was indicated that prestraining at subzero temperature followed by annealing at 600 °C leads to considerable enhancement in tensile properties and kinetics of static... 

    An investigation on tensile properties of coiled carbon nanotubes using molecular dynamics simulation

    , Article Diamond and Related Materials ; Volume 74 , 2017 , Pages 154-163 ; 09259635 (ISSN) Shahini, E ; Karimi Taheri, K ; Karimi Taheri, A ; Sharif University of Technology
    Elsevier Ltd  2017
    Abstract
    A coiled carbon nanotube (CCNT) can be formed from the distortion of parent toroidal carbon nanotube with a uniform pitch length and a uniform spring rise angle. In this research molecular dynamics simulation was carried out to assess the tensile properties of three CCNT having indexes of (3,3), (4,4), and (5,5). The results indicated that Stone-Wales defects are necessary for thermodynamic stability of the CCNTs. The stress-strain curves showed that the yield stress, yield strain, and failure strain are decreased with increase in temperature. The force-displacement curves revealed that the spring constant of these materials is highly depended on the tube diameter and rising angle, while it... 

    Microstructural evolution, mechanical properties, and corrosion resistance of a heat-treated Mg alloy for the bio-medical application

    , Article Journal of Magnesium and Alloys ; Volume 7, Issue 1 , 2019 , Pages 80-89 ; 22139567 (ISSN) Janbozorgi, M ; Karimi Taheri, K ; Karimi Taheri, A ; Sharif University of Technology
    National Engg. Reaserch Center for Magnesium Alloys  2019
    Abstract
    During the recent years, some Mg based alloys have extensively been considered as a new generation of degradable and absorbable bio-medical materials. In this work, the Mg–2Zn–1Gd–1Ca (wt%) alloy as a new metallic bio-material was produced by the casting process followed by the heat treatment. The samples of the alloy were solution treated at temperatures of 500, 550, and 600 °C and then quench aged at temperatures of 125, 150, and 175 °C. The results of SEM-EDS examinations indicated that the alloy microstructure consists of α-Mg matrix and the Ca2Mg6Zn3 and Mg3Gd2Zn3 secondary phases. With regard to the results of Vickers hardness test, the temperatures of 500 °C and 150 °C were selected... 

    A study of hyperelastic models for predicting the mechanical behavior of extensor apparatus

    , Article Biomechanics and Modeling in Mechanobiology ; Volume 16, Issue 3 , 2017 , Pages 1077-1093 ; 16177959 (ISSN) Elyasi, N ; Karimi Taheri, K ; Narooei, K ; Karimi Taheri, A ; Sharif University of Technology
    Springer Verlag  2017
    Abstract
    In this research, the nonlinear elastic behavior of human extensor apparatus was investigated. To this goal, firstly the best material parameters of hyperelastic strain energy density functions consisting of the Mooney–Rivlin, Ogden, invariants, and general exponential models were derived for the simple tension experimental data. Due to the significance of stress response in other deformation modes of nonlinear models, the calculated parameters were used to study the pure shear and balance biaxial tension behavior of the extensor apparatus. The results indicated that the Mooney–Rivlin model predicts an unstable behavior in the balance biaxial deformation of the extensor apparatus, while the... 

    Identifying Active Followership Behaviors in Interaction with Managers with Autocratic Leadership Style in an Iranian Organization

    , M.Sc. Thesis Sharif University of Technology Ghahremani, Hamed (Author) ; Alavi, Babak (Supervisor) ; Banki, Sara (Supervisor)
    Abstract
    Purpose: The purpose of this thesis was to identify active followership behaviors of followers in interaction with autocratic leaders. An active follower thinks critically and takes initiatives.
    Design: Given that Followership literature is still in its infancy, the research questions needed a qualitative approach, in this case grounded theory. In total, 19 top- & middle-level managers were interviewed as leaders and followers, accordingly, using semi-structured interviews.
    Findings: 4 categories of active followership were found, each having 3-4 specific behaviors. These categories are: precautionary behaviors, facilitating behaviors, modificating behaviors, and consolidating... 

    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... 

    An investigation on microstructure evolution, mechanical properties, and strain aging of Mg-1.8Zn-0.7Si-0.4Ca biomedical alloy processed by equal channel angular pressing

    , Article Journal of Materials Engineering and Performance ; Volume 28, Issue 8 , 2019 , Pages 5207-5219 ; 10599495 (ISSN) Shaeri, M ; Karimi Taheri, K ; Karimi Taheri, A ; Shaeri, M. H ; Sharif University of Technology
    Springer New York LLC  2019
    Abstract
    The influence of equal channel angular pressing (ECAP) on microstructure and mechanical behavior, as well as, strain aging during ECAP and post-ECAP of Mg-1.8Zn-0.7Si-0.4Ca biomedical alloy was examined. The alloy in solid solution heat-treated condition was processed by ECAP with route BC at 350 and 400 °C. The specimens ECAPed at 350 °C were aged at 125 and 150 °C for different times. The hardness and shear punch test results indicated that performing ECAP at 350 °C for 4 passes increases the hardness and shear strength of the alloy from 48 HV and 110 MPa to 71 HV and 188 MPa, respectively. It was revealed that the average grain size of the alloy decreases from 78 µm to about 3 µm after 4... 

    Applying Gamification in Corporate Entrepreneurship Culture, Specially Missionary Organizations; Through SafirFilm Case Study

    , M.Sc. Thesis Sharif University of Technology Jafarian, Hamid Reza (Author) ; Yavari, Elham (Supervisor) ; Banki, Sara ($item.subfieldsMap.e)
    Abstract
    Although existing literature on organizational culture and its change process contains meaningful and rich theories but our studies show that there is no perfect and detailed framework on linking organizational culture change and corporate entrepreneurship culture. In addition to that, Gamification –defined as taking the game design elements into non-game contexts– is a fruitful and academically rich research area. Fortunately an idea proposed recently to explain a method for enhancements in organizational culture in general, and in corporate entrepreneurship culture in particularby Yavari and Jafarian based on using game mechanisms. In their paper "A Gamification-Based Method for Corporate... 

    Synthesis of Tin and Ti2n Nanostructured Coatings on Ti alloys Using Magnetron Sputtering System And Comparison of Their Biocompatibility Properties

    , M.Sc. Thesis Sharif University of Technology Kalantari Saghafi, Mahsa (Author) ; Nemati, Ali (Supervisor) ; Khamse, Sara (Supervisor)
    Abstract
    Considering the importance of biocompatibility of implantable prothesis’, metallic alloys have weaker corrosion resistance than ceramics. In order to extend usage of nanomaterials to improve the bio-properties of materials, Nano-structured ceramic coatings are being suggested to improve corrosion resistance and biocompatibility of prosthesis. Meanwhile, very good properties of TiN, such as corrosion resistance and mechanical properties as a thin film coating are undeniable. In this study, TiN and Ti2N thin film were deposited on Ti-based substrate, using PVD and Magnetron sputtering at different argon to nitrogen ratio. The crystal structure of the films was examined using Grazing XRD... 

    The effect of deformation heating on restoration and constitutive equation of a wrought equiatomic NiTi alloy

    , Article Journal of Materials Engineering and Performance ; Volume 21, Issue 4 , April , 2012 , Pages 516-523 ; 10599495 (ISSN) Ahadi, A ; Karimi Taheri, A ; Karimi Taheri, K ; Sarraf, I. S ; Abbasi, S. M ; Sharif University of Technology
    2012
    Abstract
    In this study, a set of constitutive equation corrected for deformation heating is proposed for a near equiatomic NiTi shape memory alloy using isothermal hot compression tests in temperature range of 700 to 1000 °C and strain rate of 0.001 to 1 s -1. In order to determine the temperature rise due to deformation heating, Abaqus simulation was employed and varied thermal properties were considered in the simulation. The results of hot compression tests showed that at low pre-set temperatures and high strain rates the flow curves exhibit a softening, while after correction of deformation heating the softening is vanished. Using the corrected flow curves, the power-law constitutive equation of... 

    The Instructional Effect of Dynamic-assessment, Non-dynamic Traditional Assesment, and Non-assessment Courses on Iranian EFL Learners' Interlanguage Pragmatic Production

    , M.Sc. Thesis Sharif University of Technology Pakzadian, Sara Sadat (Author) ; Tajeddin, Zia (Supervisor) ; Alemi, Minoo (Supervisor)
    Abstract
    There are several methods proposed for the instruction and assessment of interlanguage pragmatic competence of foreign language learners. Dynamic assessment as one of the recent methods arising from Vygotsky’s sociocultural theory of mind incorporates assessment and instruction by engaging learners in a process of interaction with the mediator while the learners are trying to perform a challenging task. The present study aimed to explore the advantage of Dynamic Assessment as an instructional instrument over the Non-dynamic (traditional) Assessment and Non-assessment approaches and their effects on the Iranian intermediate level students. The target speech acts of apology, complaint, and... 

    Monitoring of Structure Characteristics, Humidity, Temperature and Torsion Using Optical Fiber Sensor

    , Ph.D. Dissertation Sharif University of Technology Esmailzadeh Noghani, Fereshteh (Author) ; Bahrampour, Alireza (Supervisor) ; Tofighi, Sara (Supervisor)
    Abstract
    Fiber optic sensors have found industrial applications due to their unique characteristics and wide range of environmental parameters. Specifically, distributed optical fiber sensors which have applications in borders protection, intrusion detection, oil and gas leakage detection and smart irrigation of farms and gardens, have attracted significant attention from research groups around the world in recent years. According to the forecasts, among all kind of optical fiber sensors, the temperature and acoustic/vibration sensors will seize the market during the coming years. In this thesis, three kind of optical fiber sensors are proposed for environment health monitoring. First, distributed... 

    Design of Tracking Control System of an Autonomous Underwater Vehicle for Following Moving Objects

    , M.Sc. Thesis Sharif University of Technology Taheri, Behzad (Author) ; Vossoughi, Gholamreza (Supervisor)
    Abstract
    Nowadays, autonomous underwater vehicles (AUVs) are implemented to carry out various activities under water. Amongst applications of these vehicles we can mention monitoring of marine creatures, mine installation and neutralization, and many military applications. The objective of this research is designing a control algorithm for underwater vehicles such that an under actuated vehicle can reckon a moving target as a reference and whilst chasing it, vehicle can keep a fixed distance from this target. First the dynamics of underwater vehicles are modeled and in this modeling different effects due to under water motion such as drag force, buoyancy force, and also added mass are included... 

    Nonlinear Seismic Interaction Behavior of Concrete Shear wall-Frame with Different Stiffness Ratio of Wall and Frame

    , M.Sc. Thesis Sharif University of Technology Taheri, Abbas (Author) ; Khaloo, Alireza (Supervisor)
    Abstract
    Wall-Frame interaction under lateral load has been considered in studies, and it is concluded that interaction lateral forces of rigid frame and shear wall varies at different stories. This is resulted from of different mode shape of rigid frame and shear wall under lateral loads which are shear and bending mode, respectively. However most codes recommend a minimum strength for frame, equal to 25% of total lateral force, as an acceptance criterion of shear wall-frame dual action; otherwise this minimum strength does not fully comply with horizontal distribution of lateral load according to relative stiffness of components.The purpose of this article is to study nonlinear seismic response of... 

    Configurable Description of Memory Organization for Low-Energy and Fault-Tolerant Embedded Processors

    , M.Sc. Thesis Sharif University of Technology Taheri, Somayye (Author) ; Ejlali, Alireza (Supervisor)
    Abstract
    Memory organization plays an important role in embedded systems. Among the various component, memories as principle of consumption large amount of energy, are more important in power consumption, real time feature and fault tolerant of system.so that depend on system application, various configuration of memory organization are used…………. Memory organization issues include memory size, memory management methods, hardware management unit, cache, SPM and theirs subject and so on. This thesis discussed important topics related to energy consumption, real time and fault tolerant feature in memory organization and purposed a Configurable Description of Memory Organization for Low-Energy and... 

    Investigation and Modeling of a New type of Semi-Rigid, Steel Beam-Column Connection under Monotonic Loading

    , M.Sc. Thesis Sharif University of Technology Taheri, Ehsan (Author) ; Mofid, Massoud (Supervisor)
    Abstract
    This thesis presents the investigation and development of a Finite Element Model (FEM) for a new type of Beam-Column Semi-Rigid steel connection. One of the main parts of this connection is a steel T profile inserted on top of a beam connecting it to a column by bolts. It seems that changes in the geometry of the T profile and its bolt positions can have a great influence on the rigidity or flexibility of the connection. Therefore, meaningful categories of the T profile geometry with different bolt positions have been modeled and analyzed by means of a Finite Element Modeling software ABAQUS, and their moment-rotation curves were driven. Also the Initial and Nonlinear Stiffness and the... 

    Acceleration Convergence of New Gradient-based Aerodynamic Optimization Algorithms

    , M.Sc. Thesis Sharif University of Technology Taheri, Ramin (Author) ; Mazaheri, Karim (Supervisor)
    Abstract
    Aerodynamic shape optimization has been always of great importance in aerospace design. Recent advancements in computational algorithms and hardware, has made it feasible to have advanced optimization as a standard part of desing procedure. Here we have promoted aerodynamic optimization in three different applications, i. e., wing-body configuration, hydro propellers, and air propellers. First we have reviewed fluidic theoretical aspects, and have selected appropriate physical models or existing softwares. Accuracy of physical analysis or software is validated. Then different optimization algorithms are reviewed, and schemes used in this thesis are described and the softwares are validated. ...