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Organizational secure knowledge flow model

, Article 2015 7th Conference on Information and Knowledge Technology, IKT 2015, 26 May 2015 through 28 May 2015 ; May , 2015 , Page(s): 1 - 6 ; 9781467374859 (ISBN) Ghaem Tajgardoon, M ; Shalmani, M. T. M ; Habibi, J ; Sharif University of Technology

Institute of Electrical and Electronics Engineers Inc 2015

Abstract

With the advance and growth of knowledge management in the past two decades, currently knowledge is regarded as one of the most significant organizational assets. Today the success of businesses is dependent on the value that they give to knowledge and how they attempt to manage it. Hence, in such conditions, knowledge as a valuable asset of the organization must be well-protected. What is managed in knowledge management in organizations is actually not knowledge. What are managed are the knowledge-related processes thru which knowledge workers interact with each other. Hence, organizational knowledge protection does not mean protecting knowledge, but securing the management of knowledge and...

Designing a Knowledge Flow Modeling Framework and Introducing a Goal-Oriented Knowledge Flow Model

, Ph.D. Dissertation Sharif University of Technology Tajgardoon, Mohammad Ghaem (Author) ; Manzuri Shalmani, Mohammad Taghi (Supervisor) ; Habibi, Jafar (Supervisor)

Abstract

The final goal of knowledge management is the creation of knowledge flows in a way that they sway the organization towards its goals. A knowledge flow model must take into account all kinds of horizontal and vertical flows at different levels, as well as providing support for organizational processes and goals. Because of lack of a framework for knowledge flow modeling, most models presented by researchers only cover part of these requirements. A framework for knowledge flow modeling facilitates the design of a complete and comprehensive model by considering all aspects and levels of knowledge flow. Hence, in this research, a framework for modeling of knowledge flow has been presented which...

Design Optimization of Linear Variable-Reluctance Resolver for Higher Accuracy and Smaller Size

, Article IEEE Sensors Journal ; Volume 23, Issue 15 , 2023 , Pages 16764-16771 ; 1530437X (ISSN) Ghaem Maghami, M ; Nasiri Gheidari, Z ; Sharif University of Technology

Institute of Electrical and Electronics Engineers Inc 2023

Abstract

Linear variable reluctance (VR) resolvers offer robustness and affordability in comparison with wound mover sensors. However, the accuracy of linear sensors is influenced by geometrical dimensions and the longitudinal end effect. In this article, the end effect was compensated by altering the teeth's shape using the tooth-pairing method. This altered shape could achieve much better accuracy. Furthermore, the influence of many different geometrical dimensions and shapes of teeth and yoke were examined using finite-element analysis (FEA). In addition, the results of this analysis show a trade-off between the accuracy and weight of the resolver in some cases. To verify the correctness of the...

Steganography Based on Sparse Decomposition

, Ph.D. Dissertation Sharif University of Technology Ahani, Soodeh (Author) ; Ghaem Maghami, Shahrokh (Supervisor)

Abstract

The goal of this thesis is using sparse decomposition to design secure steganography algorithms to insert secret data into the different cover signals. We propose data embedding in higher semantic levels of the cover signal to reach this goal. Sparse decomposition represents a signal as a linear combination of its structural elements. Data insertion into the sparse coefficients slightly changes the effect of structural elements in the signal representation. So, quality of the stego signal is preserved and such a steganography method leads to higher imperceptibility. In addition, data insertion into the higher semantic levels leads to the higher undetectability. Steganalyzers use statistical...

Speech Enhancement Using Deep Neural Networks in Non-stationary Noise Environment

, M.Sc. Thesis Sharif University of Technology Hosseini, Ehsan (Author) ; Ghaem Maghami, Shahrokh (Supervisor)

Abstract

Before performing any operation on a speech signal, it is necessary to properly remove the environmental noise existing on it. Noise Canceling Operation on Speech Signal is called speech enhancement. Up to now, many studies have been conducted on various ways to enhance the speech signal. Among the existing methods, statistical methods have proven to be superior to others. In all noise removal methods, the main challenge is that most noises are non-stationary. Since most of the noises in the environment are non-stationary, we are still looking for the better ways to remove them. With the advent of deep neural networks and their successful results in areas such as machine learning, a method...

Manipulability analysis for gimbal driven robotic arms

, Article 2009 IEEE International Conference on Robotics and Biomimetics, ROBIO 2009, 19 December 2009 through 23 December 2009 ; 2009 , Pages 1039-1044 ; 9781424447756 (ISBN) Mohammadi, F ; Hemmatian, I ; Ghaem Osgouie, K ; Sharif University of Technology

2009

Abstract

Gimbal transmissions are non-linear direct transmissions and can be used in robotic arms replacing the traditional revolute joints. To investigate manipulability of robotic manipulators, the classical criterion of Manipulability Ellipsoid has been formulated. Thus by keeping a constant norm for robot joint torques vector, the effects of replacing some traditional revolute joints in robotic arms with Gimbal transmissions, have been analyzed. The results show that the magnitude of the maximum force applicable when employing Gimbal transmission can be considerably larger. Also, the joint angles in which this maximum occurs, can be adjusted, thanks to the behavior of Gimbal transmission. Two...

Development of a Control Algorithm for Functional Electrical Stimulation to Achieve Smooth Motion

, M.Sc. Thesis Sharif University of Technology Ghaem Maghami, Horieh (Author) ; Behzadipour, Saeed (Supervisor)

Abstract

The use of functional electrical stimulation after spinal cord injury is one of the most effective ways to prevent muscle atrophy.” Enzymes construction set, torque output increases and improved fatigue resistance”.
Functional electrical stimulation devices help in the operation of a muscle by applying a weak electrical current. This stimulation causes muscle contraction. In other words, it replaces the neural signals required to move the limb that cannot be produced due to causes such as spinal cord injury (SCI) orsecondary problems that arise after SCI.
One of the drawbacks of using FES is jerky motions in the muscles and limps. Such movements are not only harmful, but results in...

Active learning of EHVS parser for Persian language understanding

, Article 2012 6th International Symposium on Telecommunications, IST 2012, 6 November 2012 through 8 November 2012 ; November , 2012 , Pages 827-832 ; 9781467320733 (ISBN) Tajgardoon, M. A ; Jabbari, F ; Sameti, H ; Bahaadini, S ; Sharif University of Technology

2012

Abstract

One of the main elements of a spoken dialogue system is the Spoken Language Understanding (SLU) unit. Hidden Vector State (HVS) is one of the popular statistical methods applied to the SLU component. Extended Hidden Vector State (EHVS) is an enhanced version of the HVS. Although both parsers need only abstract data annotation, it is quiet time consuming and difficult to label the data. Thus, we present a novel active learning method for the EHVS parser to reduce the human labeling effort. The active learner makes use of pattern classification to select the informative data based on four different uncertainty measures. Experiments are done on a Persian dataset, the University Information...

A knowledge flow framework for e-government in Iran

, Article Information Development ; Volume 32, Issue 4 , 2016 , Pages 1216-1227 ; 02666669 (ISSN) Tajgardoon, M. G ; Manzuri Shalmani, M. T ; Habibi, J ; Sharif University of Technology

SAGE Publications Ltd 2016

Abstract

Iran’s fifth Four Year Development Plan (2011-2015) and other high level acts in recent years have paid more attention to the topic of knowledge management. This in turn has encouraged the government agencies to pay special attention to this topic for the development of their regulations and future plans. The information technology field has not been an exception to this trend, and in September 2014 an Administrative and Technical Criteria Act (ATCA) was approved for the development of an agile and effective e-government in Iran. Under Article 40 of ATCA all executive bodies of government are required to design and implement a comprehensive knowledge management system within the next 2...

Audio-visual Speaker Verification Using Identity Based Articulatory Features

, M.Sc. Thesis Sharif University of Technology Keshavarz Chafjiri, Amir Hossein (Author) ; Ghaem Maghami, Shahrokh (Supervisor)

Abstract

Many companies feel the need of automatic person identification for tracking entrance and exit of their employers. This system will help the company in reducing security costs, waste of time and increasing security. In this thesis a novel idea for 3d convolutional neural network text independent speaker verification system will introduced. Since many scenarios visionary data like lip motion, besides speech data, is available, in this thesis both of these data streams are used for developing designed speaker verification system. Multimodalily helps the verification system to be more robust to the noise and attacks. One of the main challenges in designing multimodal neural network speaker...

Construction of an Experimental Device for Foaming Agent and an Experimental Study of the Properties of Foaming Agent

, M.Sc. Thesis Sharif University of Technology Mohammad Karami (Author) ; Bazargan, Mohammad (Supervisor)

Abstract

The primary purpose of acidizing operations in the oil and gas industry is to enhance hydrocarbon production. Acidizing has been a common and conventional method for years, especially when production engineers face issues like declining reservoir pressure leading to reduced production rates. Initially, the treatment solution is referred to as matrix acidizing. In acidizing operations, different additives are combined with the acid to control its behavior in the reservoir. These additives may include iron control agents, corrosion inhibitors, friction reducers, and more. Incompatibility among these additives, the acid, and reservoir fluids can lead to severe damage to the reservoir....

Numerical Analysis of An Annular Gas Turbine Combustor

, M.Sc. Thesis Sharif University of Technology Gandomi, Mohammad Hossein (Author) ; Farshchi, Mohammad (Supervisor)

Abstract

The goal of this research is the simulation of the annular combustion chamber of the turbine engine utilized by liquid fuel. The achievement to this goal will lead to create numerical tools for parametric study, analysis and combustion chamber designing.For this reason simple geometry has been considered. This simplicity of geometry causes to facilitate in parametric study and decrease in saving time for modeling and meshing. This combustion chamber is a simplified model of engine CF6. In recent study, the k – ε realizable model has been used for turbulence modeling. For non-adiabatic condition, chemical reaction is dissolved by utilizing probability density function along with laminar...

A misbehavior‐tolerant multipath routing protocol for wireless Ad hoc networks [electronic resource]

, Article International Journal of Research in Wireless Systems (IJRWS) ; Vol. 2, Issue 9, pp. , Sep. 2013 Sedghi, H. (Haniyeh) ; Pakravan, Mohammad Reza ; Aref, Mohammad Reza ; Sharif University of Technology

Abstract

Secure routing is a major key to service maintenance in ad hoc networks. Ad hoc nature exposes the network to several types of node misbehavior or attacks. As a result of the resource limitations in such networks nodes may have a tendency to behave selfishly. Selfish behavior can have drastic impacts on network performance. We have proposed a Misbehavior-Tolerant Multipath Routing protocol (MTMR) which detects and punishes all types of misbehavior such as selfish behavior, wormhole, sinkhole and grey-hole attacks. The protocol utilizes a proactive approach to enforce cooperation. In addition, it uses a novel data redirection method to mitigate the impact of node misbehavior on network...

Theoretical and Experimental Study to Conversion of AUC to UO2 by Microwave Heating

, Ph.D. Dissertation Sharif University of Technology Labbaf, Mohammad Hossein (Author) ; Otukesh, Mohammad (Supervisor) ; Ghannadi Maragheh, Mohammad (Co-Advisor) ; Ghasemi, Mohammad Reza (Co-Advisor)

SAR Imaging Using the TomoSAR Technique to Resolve Multiple Scatterers

, M.Sc. Thesis Sharif University of Technology Omati, Mohammad Mahdi (Author) ; Bastani, Mohammad Hassan (Supervisor) ; Karbasi, Mohammad (Co-Supervisor)

Abstract

During the last few years, the study of urban environment structures is considered as a research field of interest in remote sensing. In satellite observations of the earth's surface, continuous imaging in terms of time and space has caused the remote sensing technique to be proposed as a useful and efficient tool for the analysis of urban areas. Obtaining quantitative spatial information from the urban environment in fields such as determining the height of buildings plays an essential role in urban planning, monitoring damage to buildings, establishing communication bases and digital cities. During the last two decades, the use of Tomosar approach in order to reconstruct the structures of...

Estimating Possible Effects of Subsidies in Competition and Development of Fixed Broadband Internet

, M.Sc. Thesis Sharif University of Technology Mohammadi, Mohammad Ali (Author) ; Vesal, Mohammad (Supervisor) ; Rahmati, Mohammad Hossein (Supervisor)

Abstract

In this work, the dynamic competition between firms providing internet services is studied. The framework is Markov equilibrium whereby structural parameters are obtained using two-step estimations, allowing for analyzing the situation in case of subsidies for service upgrade. The results show that such subsidy has little effect on the number of firms while increasing the number of fast firms

Estimating Price Elasticity of Natural Gas Demand in Iran's Residential Sector: A Regression Discontinuity Approach

, M.Sc. Thesis Sharif University of Technology Makhsousi, Mohammad Hossein (Author) ; Rahmati, Mohammad Hossein (Supervisor) ; Vesal, Mohammad (Supervisor)

Abstract

Estimating the price elasticity of gas demand involves complexities depending on the gas market structure and pricing mechanisms in different countries. Distinguishing between supply and demand shocks and block pricing are among the main challenges that can cause endogeneity in elasticity estimates. Iran's domestic gas network, one of the largest and most extensive household gas markets, is divided into five climatic zones based on weather conditions. The pricing steps for these five climates during the five cold months are such that a customer in a warmer climate pays higher prices. Conversely, the pricing steps for the seven warm months are the same for all climates. This policy creates a...

Estimate the Effect of Religiosity on Voter Turnout

, M.Sc. Thesis Sharif University of Technology Jarrahi, Mohammad Mahdi (Author) ; Rahmati, Mohammad Hossein (Supervisor) ; Vesal, Mohammad (Supervisor)

Abstract

The correlation between religious adherence and voter turnout is widely studied. However, whether the relation is causal is an open question. We use Household Expenditures and Income Survey (HEIS) data in Iran, which encompasses nine distinct religious expenditures. These expenditures have low correlation with each other and represent different aspects of religious adherence. We use Imamzadeh (some historical holy shrines) as Instruments to estimate the causal effect of religious expenditures on voter turnout. The results reveal that religious expenditures influence both presidential and parliamentary voter turnout, with a notably stronger impact on presidential elections

Joint Optimization of Computation Offloading and Resource Allocation in Mobile Edge Computing Networks

, M.Sc. Thesis Sharif University of Technology Shokouhi, Mohammad Hossein (Author) ; Pakravan, Mohammad Reza (Supervisor) ; Hadi, Mohammad (Co-Supervisor)

Abstract

Mobile edge computing (MEC) is a promising technology that aims to resolve cloud computing’s issues by deploying computation resources at the edge of mobile network and in the proximity of users. The advantages of MEC include reduced latency, energy consumption, and load on access and mobile core networks, to name but a few. Despite all the aforementioned advantages, the mobility of mobile network users causes the traditional MEC architecture to suffer from several issues, such as decreased efficiency and frequent service interruption. One of the methods to manage users’ mobility is virtual machine (VM) migration, where the VM containing the user’s task is migrated to somewhere closer to...

Non-Scratch, Antibacterial And Self-cleaning SiO2/TiO2 Nano Composite Coating on Surgical Tools By Sol-Gel

, M.Sc. Thesis Sharif University of Technology Ahmadi, Mohammad Hossein (Author) ; Ghorbani, Mohammad (Supervisor)

Abstract

In this study TiO2/SiO2 thin films were prepared by sol-gel method from Tetra isopropylortho Titanate(TIPT) as the principle of TiO2 material with Tera ethoxysilane(TEOS) as the principle of SiO2 material to achieve high scratch-resistant , antibacterial and self-cleaning surface area under the effect of various percentage of SiO2 . Film deposition was carried out using a dip-coating technique and heat-treatment was used at 700ºC to achieve crystalline of films with excellent adherence the of substrate.
The surface morphology of the films has been observed by Scanning Electron Microscope (SEM) and the tribological properties of the surface were investigated by Atomic Force Microscope...