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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... 

    Continuous monitoring of safety performance

    , Article Total Safety and the Productivity Challenge ; 2019 , Pages 126-140 ; 9781351609074 (ISBN); 9781138091306 (ISBN) Amir-Heidari, P ; Sharif University of Technology
    Taylor and Francis  2019
    Abstract
    Key performance indicators (KPIs) are the fundamental building blocks in measuring and monitoring processes of safety management. This chapter describes a classification of safety KPIs and a review of literature leads to a new framework. It aims to develop a logical selection and aggregation methodology for generating a single number that reflects safety performance. Determining a mechanism for performance measurement and monitoring is a key part of any management system, and this has a higher importance for total safety management. Personal safety deals with the prevention of occupational accidents that usually have low severities and high frequencies. The measurement of safety has been... 

    Continuous monitoring of safety performance

    , Article Total Safety and the Productivity Challenge ; 2019 , Pages 126-140 ; 9781351609074 (ISBN); 9781138091306 (ISBN) Amir Heidari, P ; Sharif University of Technology
    Taylor and Francis  2019
    Abstract
    Key performance indicators (KPIs) are the fundamental building blocks in measuring and monitoring processes of safety management. This chapter describes a classification of safety KPIs and a review of literature leads to a new framework. It aims to develop a logical selection and aggregation methodology for generating a single number that reflects safety performance. Determining a mechanism for performance measurement and monitoring is a key part of any management system, and this has a higher importance for total safety management. Personal safety deals with the prevention of occupational accidents that usually have low severities and high frequencies. The measurement of safety has been... 

    Project Finance and Motivations and Optimum Approach of Using it in LNG Industry of Iran

    , M.Sc. Thesis Sharif University of Technology Heidari, Mahdi (Author) ; Zamani, Shiva (Supervisor)
    Abstract
    Project Finance is a novel approach in financing big projects. High debt ratio, independency to promoter credit and establishing a special purpose company, are some of project finance characteristics that could be very beneficial in some projects. Liquid Natural Gas (LNG) is a solution for exporting natural gas to far destination. As economical and environmental benefits of using natural gas have been increased in recent years, LNG industry has been experienced rapid growth. In this project we analyze project finance and then describe economical motivation of using this method in LNG industry of Iran.

     

    Effects of Cable Arrangements on Seismic Performance of Cable-stayed Bridges

    , M.Sc. Thesis Sharif University of Technology Heidari, Siamak (Author) ; Maleki, Shervin (Supervisor)
    Abstract
    Cable-stayed bridges are the most economical solution for spans ranging from about 200 to 1000 meters. They have become more popular in recent decades due to their efficiency and appearance. The need to understand their seismic beahvior is apparent and any improvement can be useful. The main purpose of this study is to determine the effect of using three lateral cable arrangement groups namely, cross system, pulley system and spatial lateral cable system with two transversally inclined cable planes on seismic performance of cable-stayed bridges. In this research, the seismic consequences of these arrangements with interactions of key parameters like, the main span length and deck to pylon... 

    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... 

    Universal image steganalysis using singular values of DCT coefficients

    , Article 2013 10th International ISC Conference on Information Security and Cryptology ; 2013 Heidari, M ; Gaemmaghami, S ; Sharif University of Technology
    IEEE Computer Society  2013
    Abstract
    We propose a blind image steganalysis method based on the Singular Value Decomposition (SVD) of the Discrete Cosine Transform (DCT) coefficients that are revisited in this work. We compute geometric mean, mean of log values, and statistical moments (mean, variance and skewness) of the SVDs of the DCT sub-blocks that are averaged over the whole image to construct a 480-element feature vector for steganalysis. These features are fed to a Support Vector Machine (SVM) classifier to discriminate between stego and cover images. Experimental results show that the proposed method outperforms most powerful steganalyzers when applied to some well-known steganography algorithms  

    Numerical Modelling of Buried Pipelines at Different Angles in Soil Slopes under Dynamic Loading Based on Physical Shaking Table Tests

    , M.Sc. Thesis Sharif University of Technology Heidari, Sina (Author) ; Jafarzadeh, Fardin (Supervisor)
    Abstract
    The purpose of presented thesis, is modeling of the buried pipelines in soil slopes under dynamic loading using experiments on the physical model. Hence, numerical models based on five physical models, which are built and experimented on Sharif University of Technology’s shaking table device, have been analyzed using ABAQUS finite element software. In each model, several pipes are buried in slope, and the angle-wise placement of pipes differs with respect to slope slide. For the purposes of modeling, the experiment box has been modeled as rigid body. In order to model the soil behavior, Strain –dependent nonlinear elasticity, and mohr-coulomb criterion, has been employed. In addition,... 

    Intelligent clustering in wireless sensor networks

    , Article 1st International Conference on Networks and Communications, NetCoM 2009, 27 December 2009 through 29 December 2009, Chennai ; 2009 , Pages 12-17 ; 9780769539249 (ISBN) Heidari, E ; Movaghar, A ; Sharif University of Technology
    2009
    Abstract
    Minimization of the number of cluster heads in a wireless sensor network is a very important problem to reduce channel contention and to improve the efficiency of the algorithm when executed at the level of cluster-heads. In this paper, we propose an efficient method based on genetic algorithms (GAs) to solve a sensor network optimization problem. Long communication distances between sensors and a sink in a sensor network can greatly drain the energy of sensors and reduce the lifetime of a network. By clustering a sensor network into a number of independent clusters using a GA, we can greatly minimize the total communication distance, thus prolonging the network lifetime. Simulation results... 

    The effect of rippled graphene sheet roughness on the adhesive characteristics of a collagen-graphene system

    , Article International Journal of Adhesion and Adhesives ; Volume 64 , 2016 , Pages 9-14 ; 01437496 (ISSN) Heidari, H ; Shamloo, A ; Sharif University of Technology
    Elsevier Ltd  2016
    Abstract
    A great amount of effort has been made in order to reach a more precise understanding of the adhesion phenomenon that happens as a vital component of several biological systems. Therefore, a firm understanding of the important factors that influence this phenomenon is of special importance in triggering the adhesive characteristics of different biological, bio-inspired and synthetic materials in fields such as tissue engineering. In this study the adhesive characteristics of a multi-material system consisting of the frequently used synthetic material, graphene, in the form of armchair-configuration sheets, and an important biological filament which is type 1 Collagen consisting of 3 alpha... 

    Modification of Crop Pattern Considering Climate Change and Efficient Use of Water Resources

    , M.Sc. Thesis Sharif University of Technology Heidari, Bita (Author) ; Moghim, Sanaz (Supervisor)
    Abstract
    In recent decades, the earth is affected by climate change and the seasons has been warmer than the last. Furthermore, the efficiency of agricultural irrigation is low, and it leads to surface water drought and decrease in groundwater level. The Middle East is known for its warm desert climate. Lack of water resources is considered the most limiting factor for sustainable agriculture and water management of irrigation is a crucial issue for agriculture in Middle East. So it’s necessary to devote the cropping pattern considering above changes. The FAO56 Penman-Monteith equation is the standardized ETo equation. A comparison was made between 8 selected methods and FAO56-PM. Thus the method... 

    Kinetics of Incomplete Reduction of Hematite Low Grade Iron Ore to Magnetite Using Mixture of CO and CO2

    , M.Sc. Thesis Sharif University of Technology Heidari, Aidin (Author) ; Halali, Mohammad (Supervisor)
    Abstract
    In this research the process of incomplete reduction of hematite low iron ore to magnetite in a fluidized bed reactor was investigated. Temperature, composition of reduction air, particle size, and stay time were investigated as effective parameters. In this way, temperatures of 560, 580, 600, 620 and 640 degrees of centigrade, input air with flows of 1.2, 1.3 and 1.4 l/s, particles size of 425-850 µm, 850 µm-1.4 mm, and 1.4-2 mm, stay times of 4, 8, 12, 16, and 20 min were used in this research. The reduced specimens were analyzed by XRD and chemical analysis. The results illustrated that increase of temperature, decrease of input air flow, decrease of particles size, and increase of stay... 

    Using makeup water to recycle cooling tower evaporated water: A feasibility study using experimental data

    , Article International Journal of Energy Technology and Policy ; Volume 17, Issue 3 , 2021 , Pages 227-238 ; 14728923 (ISSN) Heidari, A ; Heidari, E ; Sharif University of Technology
    Inderscience Publishers  2021
    Abstract
    Wet cooling towers are one of the most water-intensive technologies, which are widely used in air conditioning applications, especially in dry regions. Considering the current water crisis around the world, it is essential to improve the design of these cooling towers to reduce their water consumption, while maintaining their cooling performance. Makeup water of cooling tower is usually a constant-temperature water which is cold enough to condensate the moisture content of the cooling tower exhaust air. Therefore, it has great potential to recycle water evaporation of cooling towers, which is not considered so far. This paper investigates a novel design for cooling towers utilising the... 

    Fabrication the Hydrogel Microfibers Using Bioprinter with Application in Cardiovascular Model

    , M.Sc. Thesis Sharif University of Technology Heidari, Faranak (Author) ; Saadatmand, Maryam (Supervisor)
    Abstract
    Cardiovascular disease (CVD) currently remains a considerable challenge for clinical treatments. CVDs account for N17.5 million deaths per year and will predictably increase to 23.6 million by 2030. The main purpose is to create human model systems to study the effect of disease mutations or drug treatment on the heart. In addition, engineered cardiac tissues are considered promising candidates to be transplanted to improve the function of diseased hearts. For engineered active tissues/organs, 3D bioprinting can fabricate complex tissue architecture with a spatiotemporal distribution of bioactive substances (cells, growth factors, and others) to better guide tissue regeneration. However,... 

    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... 

    The Motility of Lipid Vesicles Due to Phase Transition in Transmemerance Proteine

    , M.Sc. Thesis Sharif University of Technology Heidari, Maziar (Author) ; Jalali, Mir Abbas (Supervisor)
    Abstract
    Phospholipid vesicles are able to carry drugs or DNA to infected or cancerous cells. The blood flow can carry them to their target positions but their performance will be enhanced if they complete their attack by swimming in final stages of their journey. Vesicles built only by lipid molecules have rotational symmetry and undergo a random motion in their solvents without having a preferred direction. In this project, we break the symmetrical shape of phospholipid vesicles by a cluster of transmembrane proteins. We use a triangulated model of the membrane, apply the method of multi-particle collision dynamics to the motion of solvent particles, and simulate the motility of vesicles for... 

    Analysis of Sensitivity of Features to Data Embedding in Blind Image Steganalysis

    , M.Sc. Thesis Sharif University of Technology Heidari, Mortaza (Author) ; Ghaemmaghami, Shahrokh (Supervisor)
    Abstract
    Steganalysis is the science of detecting covert communication. It is called blind (universal) if designed to detect stego images steganographied by a wide range of embedding methods. In this method, statistical properties of the image are explored, regardless the embedding procedure employed. The main problem for image steganalysis is to find sensitive features and characteristics of the image which make a statistically significant difference between the clean and stego images. In this thesis we propose a blind image steganalysis method based on the singular value decomposition (SVD) of the discrete cosine transform (DCT) coefficients that are revisited in this work in order to enhance the... 

    Flood Routing Studies, Dambreak Modeling – Case Study: Shahrchay Dam

    , M.Sc. Thesis Sharif University of Technology Heidari, Mohammad Reza (Author) ; Jafarzadeh, Fardin (Supervisor)
    Abstract
    Due to several reasons such as water deficiency and gradual reduce in water resources, dams had always been prominent during past centuries. Most of the dams have been built proximate to cities to provide water for drinking and industries thus, it’s vital to examine them in the aspects of safety factor and capacity to contain overflow. Failure of the dames should also studied considering different features such for instance sudden increment of stored water behind the dam as a result of gigantic floods, leakage in the body of soil dams, overflow in the dam crest due to insufficient functionality of spillway and etc. which could cause the failure of dams.
    The main purpose of this thesis...