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Human Action Recognition Using Depthmap Image Sequences for Abnormal Event Detection
,
M.Sc. Thesis
Sharif University of Technology
;
Mohammadzadeh, Hoda
(Supervisor)
Abstract
The human action recognition is one of the most important concepts of computer vision in recent decades. Most of the two dimensional methods in this field are facing serious challenges such as occlusion and missing the third dimension of data. Development of depth sensors has made easy access to tracking people and 3D positions of human body joints. This Thesis proposes a new method of action recognition that utilizes the position of joints obtained by Kinect sensor. The learning stage uses Fisher Linear Discriminant Analysis (LDA) to construct discriminant feature space. Two types of distances, i.e., Euclidean and Mahalanobis, are used for recognizing the states. Also, Hidden Markov Model...
Cross-Domain EEG-Based Emotion Recognition
, M.Sc. Thesis Sharif University of Technology ; Mohammadzadeh, Hoda (Supervisor)
Abstract
The non-stationary nature of brain activity signals and their many inter-subject differences have created many challenges in the practical applications of emotion recognition based on electroencephalogram (EEG) signals, such as brain-computer interfaces. In such a way, the use of traditional classifiers in classifying these signals leads to a significant decrease in accuracy when applying the classifier to a new subject. Domain Adaptation methods seem to be an effective way to solve this problem by minimizing the difference between the EEG signals of different subjects. But in the basic techniques for domain adaptation, looking at all subjects' data in the same look causes the loss of a part...
Factors influencing adoption of e-payment systems: an empirical study on Iranian customers
, Article Information Systems and e-Business Management ; Volume 15, Issue 1 , 2017 , Pages 89-116 ; 16179846 (ISSN) ; Nourollah, Z ; Mashayekhi, H ; Mashayekhi, Y ; Ahangar, M. S ; Sharif University of Technology
Springer Verlag
2017
Abstract
Internet technology has influenced the banking systems because of its capability to enhance performance of financial operations. A major concern of Internet banking systems is the customers’ perception of security and trust. This study presents an experimental investigation on important factors influencing trust in e-payments systems in Iran. A set of potentially determinant factors of trust is developed and organized in three major groups: technical and transaction procedures, access to security guidelines, and usability. The direct effect of the factors on perceived trust, along with their indirect effect through perceived security, is evaluated in an empirical study. The data are...
Auto-selection of space-time Interest Points for Action Recognition
Application in Fisherposes Method
,
M.Sc. Thesis
Sharif University of Technology
;
Mohammadzadeh, Narges Hoda
(Supervisor)
Abstract
In this project, a novel action recognition method, named Fisherposes, is proposed, which is improved by several space-time (spatio-temporal) methods afterwards. The proposed method utilizes skeleton data obtained from Kinect sensor. First, pre-processing is performed in which the scales of bodies are canceled and the skeletons become aligned in order to make the method robust to location, orientation, and scale of people. In Fisherposes method, every action is defined as a sequence of body poses. Using the training samples for the poses, a Fisher subspace is created which we name it Fisherposes. Moreover, a novel distance measuring function, named regularized Mahalanobis distance, is...
Project cost dynamics for development policy-making
, Article Journal of the Operational Research Society ; Volume 51, Issue 3 , 2000 , Pages 301-310 ; 01605682 (ISSN) ; Sharif University of Technology
2000
Abstract
Cost and time overruns have been a common characteristic of development projects in many countries. This paper presents a theory of cost and time overruns based on project cost structure. The cost of a development project consists of base cost and progress cost. Base cost keeps a project ready for physical progress. Progress cost creates real physical progress on the project. This cost structure has an important inherent dynamic characteristic with implications for the efficiency and effectiveness of project management. An imbalance between annual budget and ongoing projects results in an increasing inefficiency and ineffectiveness unrelated to the quality of management of individual...
Cysteic acid grafted to magnetic graphene oxide as a promising recoverable solid acid catalyst for the synthesis of diverse 4H-chromene
, Article Scientific Reports ; Volume 10, Issue 1 , December , 2020 ; Eslami, M ; Hoda, G ; Sharif University of Technology
Nature Research
2020
Abstract
4H-chromenes play a significant role in natural and pharmacological products. Despite continuous advances in the synthesis methodology of these compounds, there is still a lack of a green and efficient method. In this study, we have designed cysteic acid chemically attached to magnetic graphene oxide (MNPs·GO-CysA) as an efficient and reusable solid acid catalyst to synthesize 4H-chromene skeletons via a one-pot three components reaction of an enolizable compound, malononitrile, an aldehyde or isatin, and a mixture of water–ethanol as a green solvent. This new heterogeneous catalyst provides desired products with a good to excellent yield, short time, and mild condition. This procedure...
The Use of Social Marketing Approach to Motivate Schools to Teach Students Systematic Thinking
, M.Sc. Thesis Sharif University of Technology ; Mashayekhi, Alinaghi (Supervisor)
Abstract
One of Iran’s most important priorities at present is the development of the human resources and one of the most important skills of this human resource is decision making and problem solving. During the past few years, there have been numerous criticisms about the educational system in Iran without a substantial solution being offered to replace the existing approach. Aseman Group has been trying to promote system thinking in children. In Aseman, they believe that system thinking is one probable solution in order to develop thinking, decision making and problem solving skills in our human resource at early age. However, one of the many problems facing this group, is the resistance shown by...
Organizational Learning Measurement in Organizational Processes: A Case Study in Assessing Learning in New Product Development in System Group Co.
,
M.Sc. Thesis
Sharif University of Technology
;
Mashayekhi, Alinaghi
(Supervisor)
Abstract
Organizational learning is essential for organizations to grow and survive. Organizations can gain competitive advantage through proper organizational learning. Number of studies in this field in recent years shows the importance of this issue among practioners and academics. The first step in managing organzaitonal learning is its measurement. Organizations can be provided with solutions if an appropriate measurement tool is designed. The main question of this research is whether this tool can be designed or not so that organizational learning in organizational processes can be measured. Despite the significance of organizational learning measurement, the current studies in this field lack...
Distributed Data Mining in Peer-to-Peer Systems
, Ph.D. Dissertation Sharif University of Technology ; Habibi, Jafar (Supervisor)
Abstract
Peer-to-peer (P2P) computing is a popular distributed computing paradigm for many applications which in-volve exchange of information among a large number of peers. In such applications, large amount of data is distributed among multiple dispersed sources. Therefore, data analysis is challenging due to processing, storage and transmission costs. Moreover, the data rarely remains static and frequent data changes, quickly out date previously extracted data mining models. Distributed data mining deals with the problem of data analysis in environments with distributed data and computing resources. In this dissertation, we explore distributed data mining in different structures of P2P systems. In...
L-overlay: A layered data management scheme for peer-to-peer computing
, Article Peer-to-Peer Networking and Applications ; Vol. 7, issue. 2 , 2014 , Pages 199-212 ; ISSN: 19366442 ; Habibi, J ; Sharif University of Technology
2014
Abstract
Efficient storage and handling of data stored in a peer-to-peer (P2P) network, proves vital for various applications such as query processing and data mining. This paper presents a distributed, scalable and robust layered overlay (L-overlay) to index and manage multidimensional data in a dynamic P2P network. The proposed method distinguishes between the data and peer layers, with efficient mapping between the two. The data is organized such that semantically similar data objects are accessed hastily. Grid and tree structures are proposed for the peer layer. As application examples of L-overlay in query processing and data mining, k-nearest neighbors query processing and distributed Naïve...
Uniquely decodable codes with fast decoder for overloaded synchronous CDMA systems
, Article IEEE Transactions on Communications ; Volume 60, Issue 11 , 2012 , Pages 3145-3149 ; 00906778 (ISSN) ; Marvasti, F ; Sharif University of Technology
2012
Abstract
In this paper, we introduce a new class of sigature matrices for overloaded synchronous CDMA systems that have a very low complexity decoder. While overloaded systems are more efficient from the bandwidth point of view, the Maximum Likelihood (ML) implementation for decoding is impractical even for moderate dimensions. Simulation results show that the performance of the proposed decoder is very close to that of the ML decoder. Indeed, the proposed decoding scheme needs neither multiplication nor addition and requires only a few comparisons. Furthermore, the computational complexity and the probability of error vs. Signal to Noise Ratios (SNR) are derived analytically
K-nearest neighbor search in peer-to-peer systems
, Article AP2PS 2010 - 2nd International Conference on Advances in P2P Systems ; 2010 , Pages 100-105 ; 9781612081021 (ISBN) ; Habibi, J ; Sharif University of Technology
2010
Abstract
Data classification in large scale systems, such as peer-to-peer networks, can be very communication-expensive and impractical due to the huge amount of available data and lack of central control. Frequent data updates pose even more difficulties when applying existing classification techniques in peer-to-peer networks. We propose a distributed, scalable and robust classification algorithm based on k-nearest neighbor estimation. Our algorithm is asynchronous, considers data updates and imposes low communication overhead. The proposed method uses a content based overlay structure to organize data and moderate the number of query messages propagated in the network. Simulation results show that...
Combining search and trust models in unstructured peer-to-peer networks
, Article Journal of Supercomputing ; Volume 53, Issue 1 , July , 2010 , Pages 66-85 ; 09208542 (ISSN) ; Habibi, J ; Sharif University of Technology
2010
Abstract
Effectiveness of Peer-to-Peer (P2P) systems highly depends on efficiency and scalability of their search algorithms. Moreover, managing trust is a key issue for wide acceptance of P2P computing. Surprisingly, the majority of the available trust systems ignore the underlying search algorithm and assume it is preexisting. We claim that combining search and trust systems yields significant performance gains in terms of network traffic and query success rate. In this paper, we propose a robust and efficient trust based search framework for unstructured P2P networks. Our framework maintains limited size routing indexes combining search and trust data to guide queries to most reputable nodes. By...
A System Dynamics Approach to Understanding the Dynamics of the Increase of Health Expenditures Share of GDP in Germany
, M.Sc. Thesis Sharif University of Technology ; Mashayekhi, Alinaghi (Supervisor)
Abstract
The main question of this research is this: what mechanisms drive the increase of the share of health costs in GDP in Germany? Answering this question not only improves our understanding about health systems in general, but also is specifically useful for the health system of Iran, since it is experiencing similar trends as the health system of Germany does. Since these mechanisms are complex and the ability of human brain to process several interacting variables simultaneously is low, we need a strong methodology and a tool to overcome this limitation. System thinking as a methodology and system dynamics as its tool help us do so. Using system dynamics, we will develop a computer model...
Design of Efficient Algorithms for Cuff-less and Continuous Estimation of Blood Pressure in Smart Mobile Healthcare Systems
, M.Sc. Thesis Sharif University of Technology ; Shabany, Mahdi (Supervisor) ; Mohammadzadeh, Hoda (Co-Advisor)
Abstract
Continuous Blood Pressure monitoring can provide invaluable information about individuals’ health conditions. However, BP is conventionally measured using inconvenient cuff-based instruments, which prevents continuous BP monitoring. This work presents an efficient algorithm, based on the Pulse Arrival Time (PAT), for the continuous and cuff-less estimation of the Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP), and Mean Arterial Pressure (MAP) values. The proposed framework estimates the BP values through processing vital signals and extracting two types of features, which are based on either physiological parameters or whole-based representation of vital signals. Finally, the...
Designing EEG-based Deep Neural Network for Analysis of Functional and Effective Brain Connectivity
, M.Sc. Thesis Sharif University of Technology ; Mohammadzadeh, Hoda (Supervisor) ; Amini, Arash (Supervisor)
Abstract
Brain states analysis during consciousness is emerging research in brain-computer interface(BCI). Emotion recognition can be applied to learn brain states and stages of neural activities. Therefore, emotion recognition is crucial to the analysis of brain functioning. Electrical signals such as electroencephalogram (EEG), electrocardiogram (ECG) and functional magnetic resonance imaging(fMRI) are frequently used in emotion recognition researches. Convenience in recording, non-invasive nature and high temporal resolution are the factors that have made EEG popular in brain researches. EEG can be used to identify brain region activity solely or the connectivity of various regions in time in the...
Determining the Challenges to change the Project-based Strategy into Product-Based Strategy and the Solutions to Confront them in Iranian Companies
,
M.Sc. Thesis
Sharif University of Technology
;
Mashayekhi, Alinaghi
(Supervisor)
Case Study of Absorption Capacity Growth Mechnisms in Farab and Bootan
, M.Sc. Thesis Sharif University of Technology ; Mashayekhi, Ali Naghi (Supervisor)
Abstract
In this study; technology transfer to the Farab and Butan fromabsorptive capacity perspective is under inquiry. First we have complete literature review until we can provide good understanding toward absorptive capacity concept in organizational level. George and Zahra model has been chosen as a base model. Farab and Butan have chosen because of their recent successes in knowledge transfer. Based on George and Zahra model we develop a semi-structured questionnair and run it in Farab and Butan. We have findings in how organization can transfer knowledge to their networks to increase their AC, also we have findings in different ways organizations transfer different kinds of knowledge
Investigation of strong-motion duration consistency in Endurance Time excitation functions
, Article Scientia Iranica ; Vol. 20, issue. 4 , 2014 , p. 1085-1093 ; 10263098 ; Estekanchi, H. E ; Sharif University of Technology
2014
Abstract
The Endurance Time (ET) method is a dynamic analysis procedure using intensifying excitation. The ET excitation functions are generated so that structural performance can be assessed at different excitation levels in a single response history analysis. ET accelerograms, which have been generated so far, possess response spectra consistency; this means that the duration consistency has not been directly considered. Strong-motion duration can influence the response of structures which have stiffness or strength degrading characteristics. In this paper, several well-known strong-motion duration definitions are studied in the context of the ET method. Ground motions are scaled to spectral...
Significance of effective number of cycles in endurance time analysis
, Article Asian Journal of Civil Engineering ; Volume 13, Issue 5 , 2012 , Pages 647-657 ; 15630854 (ISSN) ; Estekanchi, H. E ; Sharif University of Technology
AJCE
2012
Abstract
Endurance Time (ET) method is a dynamic analysis procedure using intensifying accelerograms which can be used to assess the structural performance at different excitation levels. In generation process of current ET accelerograms, the compatibility between acceleration spectrum produced by the ET accelerograms and acceleration spectrum associated with the real ground motions is applied, whereas the duration consistency is not directly considered. It is generally accepted that the strong-motion duration can strongly influence the response of structures which have stiffness or strength degrading characteristics. In this study, the number of cycles that a structure should resist due to a ground...