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    Introduction to stochastic processes

    , Article Understanding Complex Systems ; 2019 , Pages 9-18 ; 18600832 (ISSN) Rahimi Tabar, M. R ; Sharif University of Technology
    Springer Verlag  2019
    Abstract
    In this chapter we provide mathematical tools to study the stochastic process from the physical point of view. © 2019, Springer Nature Switzerland AG  

    Introduction to stochastic processes

    , Article Understanding Complex Systems ; 2019 , Pages 9-18 ; 18600832 (ISSN) Rahimi Tabar, M. R ; Sharif University of Technology
    Springer Verlag  2019
    Abstract
    In this chapter we provide mathematical tools to study the stochastic process from the physical point of view. © 2019, Springer Nature Switzerland AG  

    Persistent homology analysis of multiqubit entanglement

    , Article Quantum Information and Computation ; Volume 20, Issue 5-6 , July , 2020 , Pages 375-399 Mengoni, R ; Di Pierro, A ; Memarzadeh, L ; Mancini, S ; Sharif University of Technology
    Rinton Press Inc  2020
    Abstract
    We introduce a homology-based technique for the classification of multiqubit state vectors with genuine entanglement. In our approach, we associate state vectors to data sets by introducing a metric-like measure in terms of bipartite entanglement, and investigate the persistence of homologies at different scales. This leads to a novel classification of multiqubit entanglement. The relative occurrence frequency of various classes of entangled states is also shown. © Rinton Press  

    Symbiotic evolution to avoid linkage problem

    , Article Studies in Computational Intelligence ; Volume 157 , 2008 , Pages 285-314 ; 1860949X (ISSN) ; 9783540850670 (ISBN) Halavati, R ; Bagheri Shouraki, S ; Sharif University of Technology
    2008
    Abstract
    In this chapter, we introduce Symbiotic Evolutionary Algorithm (SEA) as a template for search and optimization based on partially specified chromosomes and symbiotic combination operator. We show that in contrast to genetic algorithms with traditional recombination operators, this template will not be bound to linkage problems. We present three implementations of this template: first, as a pure algorithm for search and optimization, second, as an artificial immune system, and third, as an algorithm for classifier rule base evolution, and compare implementation results and feature lists with similar algorithms. © 2008 Springer-Verlag Berlin Heidelberg  

    Rotated general regression neural network

    , Article 2007 International Joint Conference on Neural Networks, IJCNN 2007, Orlando, FL, 12 August 2007 through 17 August 2007 ; 2007 , Pages 1959-1964 ; 10987576 (ISSN) ; 142441380X (ISBN); 9781424413805 (ISBN) Gholamrezaei, M ; Ghorbanian, K ; Sharif University of Technology
    2007
    Abstract
    A rotated general regression neural network is presented as an enhancement to the general regression neural network. A variable kernel estimate for multivariate densities is considered. A coordinate transformation is adopted which circumvent the difficulty of predicting multimodal distribution with large variance differences between modes which is associated with the general regression neural network. The proposed technique trains the network in a way that the variance differences between modes is kept small and in the same order. Further, the technique reduces the number of indispensable training parameters to two parameters and lowers the load of the computation as well as the time for... 

    Computer intrusion detection using an iterative fuzzy rule learning approach

    , Article 2007 IEEE International Conference on Fuzzy Systems, FUZZY, London, 23 July 2007 through 26 July 2007 ; 2007 ; 10987584 (ISSN) ; 1424412102 (ISBN); 9781424412105 (ISBN) Saniee Abadeh, M ; Habibi, J ; Sharif University of Technology
    2007
    Abstract
    The process of monitoring the events occurring in a computer system or network and analyzing them for sign of intrusions is known as intrusion detection system (IDS). The objective of this paper is to extract fuzzy classification rules for intrusion detection in computer networks. The proposed method is based on the iterative rule learning approach (IRL) to fuzzy rule base system design. The fuzzy rule base is generated in an incremental fashion, in that the evolutionary algorithm optimizes one fuzzy classifier rule at a time. The performance of final fuzzy classification system has been investigated using intrusion detection problem as a high-dimensional classification problem. Results show... 

    Comparing performance of metaheuristic algorithms for finding the optimum structure of CNN for face recognition

    , Article International Journal of Nonlinear Analysis and Applications ; Volume 11, Issue 1 , 2020 , Pages 301-319 Rikhtegar, A ; Pooyan, M ; Manzuri, M. T ; Sharif University of Technology
    Semnan University, Center of Excellence in Nonlinear Analysis and Applications  2020
    Abstract
    Local and global based methods are two main trends for face recognition. Local approaches extract salient features by processing different parts of the image whereas global approaches find a general template for face of each person. Unfortunately, most global approaches work under controlled envi-ronments and they are sensitive to changes in the illumination. On the other hand, local approaches are more robust but finding their optimal parameters is a challenging task. This work proposes a new local-based approach that automatically tunes its parameters. The proposed method incorporates different techniques. In the first step, convolutional neural network (CNN) is employed as a trainable... 

    Quine-McCluskey classification

    , Article 2007 IEEE/ACS International Conference on Computer Systems and Applications, AICCSA 2007, Amman, 13 May 2007 through 16 May 2007 ; 2007 , Pages 404-411 ; 1424410312 (ISBN); 9781424410316 (ISBN) Safaei, J ; Beigy, H ; Sharif University of Technology
    2007
    Abstract
    In this paper the Karnaugh and Quine-McCluskey methods are used for symbolic classification problem, and then these methods are compared with other famous available methods. Because the data in classification problem is very large, some changes should be applied in the original Quine-McCluskey (QMC) algorithm. We proposed a new algorithm that applies the QMC algorithm greedily calling it GQMC. It is surprising that GQMC results are most of the time equal to QMC. GQMC is still very slow classifier and it can be used when the number of attributes of the data is small, and the ratio of training data to the all possible data is high. © 2007 IEEE  

    A method to estimate surface soil moisture and map the irrigated cropland area using sentinel-1 and sentinel-2 data

    , Article Sustainability (Switzerland) ; Volume 13, Issue 20 , 2021 ; 20711050 (ISSN) Rabiei, S ; Jalilvand, E ; Tajrishy, M ; Sharif University of Technology
    MDPI  2021
    Abstract
    Considering variations in surface soil moisture (SSM) is essential in improving crop yield and irrigation scheduling. Today, most remotely sensed soil moisture products have difficulties in resolving irrigation signals at the plot scale. This study aims to use Sentinel-1 radar backscatter and Sentinel-2 multispectral imagery to estimate SSM at high spatial (10 m) and temporal resolution (at least 5 days) over an agricultural domain. Three supervised machine learning algorithms, multilayer perceptron (MLP), a convolutional neural network (CNN), and linear regression models, were trained to estimate changes in SSM based on the variation in surface reflectance and backscatter over five... 

    The online atlas of the languages of Iran: Design, methodology and initial results

    , Article Language Related Research ; Volume 12, Issue 2 , 2021 , Pages 231-291 ; 23223081 (ISSN) Taheri Ardali, M ; Anonby, E ; Hayes, A ; Azin, Z ; Ebrahimi, Z ; Öpengin, E ; Atabaki, N. A ; Stone, A ; Stilo, D ; Esmaeelpour, E ; Amani Babadi, M ; Ourang, M ; Izadi, E ; Oikle, R ; Bahrani, N ; Borjian, H ; Bahrami, A ; Poshtvan, H ; Piryaee, S ; Pishyardehkordi, P ; Sabethemmatabadi, P ; Jaafari Dehaghi, S ; Doab, M. J ; Jamaleddin, F ; Joulaei, K ; Shabaniyan, H. H ; Khanjani, J ; Dianat, L ; Rashidi, A ; Borujeni, R. R ; Rahnema, Z ; Zamani Gandomani, Z ; Schreiber, L ; Sherafat, N ; Sheyholislami, J ; Salehi, M ; Talebi Dastenaei, M ; Kasgari, A. A. A ; Ghiasian, M. S ; Fattahi, M ; Ghandi, S ; Gheitasi Doolabi, M ; Kamali, R ; Goshtasb, F ; Bahmani, H. M ; Mohammadi, M ; Moradi, R ; Meshkinfam, M ; Khoo, R. M ; Bahram, A. N ; Nemati, F ; Nourzaei, M ; Wang, E ; Hashemi Zarajabad, H ; Sharif University of Technology
    Tarbiat Modares University  2021
    Abstract
    Iran is home to a treasury of languages representing diverse language families: Iranic, Turkic, Semitic, Indic, Dravidian, Armenian, and Kartvelian, as well as sign languages. Despite valuable research carried out by Iranian and western scholars, there is still no comprehensive publication depicting the geographic distribution and linguistic status of language varieties in Iran. In order to work toward this goal, the Atlas of the Languages of Iran (ALI) (www.iranatlas.net) was officially launched in 2015 as an international, online research programme. The present study opens with a historical overview of the research context and underlines the ongoing necessity of constructing such an atlas... 

    An adaptive approach to singular point detection in fingerprint images

    , Article AEU - International Journal of Electronics and Communications ; Volume 58, Issue 5 , 2004 , Pages 367-370 ; 14348411 (ISSN) Rahimi, M. R ; Pakbaznia, E ; Kasaei, S ; Sharif University of Technology
    Elsevier GmbH  2004
    Abstract
    This paper presents a novel algorithm for detection of singular points, the core and delta points, in fingerprint images. The number and location of singular points, are used to classify fingerprint images into five general groups; and therefore to narrow down the search space in large fingerprint databases. Using the proposed directional masks in the first step, we detect the neighborhood of the singular points. In the second stage by implementing the proposed algorithm, an adaptive singular point detection method, is designed to extract the exact location of core and delta points. Usage of the proposed directional masks speeds up the process and the proposed adaptive singular point... 

    Security Policy Enforcement on Heavy Network Traffic

    , M.Sc. Thesis Sharif University of Technology Sadeghzadeh Mesgar, Amir Mahdi (Author) ; Jalili, Rasool (Supervisor)
    Abstract
    Today’s large networks, such as global enterprise networks, carry heavy network traffic from a wide range of diverse protocols. Scalable and accurate classifcation of network traffic is of the most importance to security policy enforcement of large networks. The complexity of current network traffic along with the high speed links makes traffic classification more difficult. The dynamicity of heavy network traffic have necessitated the need for traffic classification algorithms which are adaptable to new concepts. The changes in traffic characteristic over time lead to concept drift, which is an important challenge in this domain. Data stream classification methods have been introduced to... 

    A Hybrid Method for Improving the Color Constancy in Images

    , M.Sc. Thesis Sharif University of Technology Abedini, Zeinab (Author) ; Jamzad, Mansour (Supervisor)
    Abstract
    The ability of measuring colors of objects, independent of light source illumination, is called color constancy which is an important field in machine vision and image processing. In this thesis, we propose five new combinantional ways in color constansy fields. The first two proposed methods use neural networks to combining basic methods. The third and forth proposed methods use fuzzy measures and integrals for combining color constancy methods. And finally fifth method combines methods with indoor outdoor classification this method has the best result (3.01 median angular error) in proposed methods and past methods in color constancy fields. It is shown in this article that the proposed... 

    Video Scene Recognition

    , M.Sc. Thesis Sharif University of Technology Diba, Ali (Author) ; Ghanbari, Mohammad (Supervisor)
    Abstract
    Scene classification and understanding is one of the most important fields in computer vision. Its applications are such as exploring robot navigation enviroment, content-based image retrieval (CBIR), organization in image databases, highly semantic describing images and videos and content extraction of videos.Many methods and algorithm are proposed till today to deal with diversity of this field by emphesizing on feature based methods or machine learning based methods. In this research we have focoused on proposing a new algorithm which is using principals of NBNN image classification method but major changes in how to exract distance metric from Nearest neighbour and how to use local... 

    Hierarchical Classification of Mobile App Reviews

    , M.Sc. Thesis Sharif University of Technology Mazraeh Khatiri, Sajad (Author) ; Heydarnoori, Abbas (Supervisor)
    Abstract
    Mobile application marketplaces are not only a distribution platform but also a place for users to give feedback on their experience with application. User reviews contain useful information for software evolution tasks including bug reports, user experience, and feature requests. Considering the massive number of reviews that popular apps receive every day, manual inspection of reviews is not feasible in many cases. Researchers have developed automated tools to classify reviews into fixed and general-purpose categories related to software evolution in order to assist developers. Although this classification can reduce the time and effort for mobile developers, it does not consider the... 

    Diagnosis of Depressive Disorder using Classification of Graphs Obtained from Electroencephalogram Signals

    , M.Sc. Thesis Sharif University of Technology Moradi, Amir (Author) ; Hajipour, Sepideh (Supervisor)
    Abstract
    Depression is a type of mental disorder that is characterized by the continuous occurrence of bad moods in the affected person. Studies by the World Health Organization (WHO) show that depression is the second disease that threatens human life, and eight hundred thousand people die due to suicide every year. In order to reduce the damage caused by depression, it is necessary to have an accurate method for diagnosing depression and its rapid treatment, in which electroencephalogram (EEG) signals are considered as one of the best methods for diagnosing depression. Until now, various researches have been conducted to diagnose depression using electroencephalogram signals, most of which were... 

    Many-Class Few-Shot Classification

    , M.Sc. Thesis Sharif University of Technology Fereydooni, Mohammad Reza (Author) ; Soleymani Baghshah, Mahdieh (Supervisor)
    Abstract
    Few-shot learning methods have achieved notable performance in recent years. However, fewshot learning in large-scale settings with hundreds of classes is still challenging. In this dissertation, we tackle the problems of large-scale few-shot learning by taking advantage of pre-trained foundation models. We recast the original problem in two levels with different granularity. At the coarse-grained level, we introduce a novel object recognition approach with robustness to sub-population shifts. At the fine-grained level, generative experts are designed for few-shot learning, specialized for different superclasses. A Bayesian schema is considered to combine coarse-grained information with... 

    SR-NBS: A fast sparse representation based N-best class selector for robust phoneme classification

    , Article Engineering Applications of Artificial Intelligence ; Vol. 28 , 2014 , pp. 155-164 Saeb, A ; Razzazi, F ; Babaie-Zadeh, M ; Sharif University of Technology
    Abstract
    Although exemplar based approaches have shown good accuracy in classification problems, some limitations are observed in the accuracy of exemplar based automatic speech recognition (ASR) applications. The main limitation of these algorithms is their high computational complexity which makes them difficult to extend to ASR applications. In this paper, an N-best class selector is introduced based on sparse representation (SR) and a tree search strategy. In this approach, the classification is fulfilled in three steps. At first, the set of similar training samples for the specific test sample is selected by k-dimensional (KD) tree search algorithm. Then, an SR based N-best class selector is... 

    Optimal temporal resolution for decoding of visual stimuli in inferior temporal cortex

    , Article 2014 21st Iranian Conference on Biomedical Engineering, ICBME 2014 ; 2014 , pp. 109-112 Babolhavaeji, A ; Karimi, S ; Ghaffari, A ; Hamidinekoo, A ; Vosoughi-Vahdat, B ; Sharif University of Technology
    Abstract
    Inferior temporal (IT) cortex is the most important part of the brain and plays an important role in response to visual stimuli. In this study, object decoding has been performed using neuron spikes in IT cortex region. Single Unit Activity (SUA) was recorded from 123 neurons in IT cortex. Pseudo-population firing rate vectors were created, then dimension reduction was done and an Artificial Neural Network (ANN) was used for object decoding. Object decoding accuracy was calculated for various window lengths from 50 ms to 200 ms and various window steps from 25 ms to 100 ms. The results show that 150 ms length and 50 ms window step size gives an optimum performance in average accuracy  

    Optimal supervised feature extraction in internet traffic classification

    , Article IEEE Pacific RIM Conference on Communications, Computers, and Signal Processing - Proceedings ; 2013 , Pages 102-107 ; 1555-5798 (ISSN) ; 9781479915019 (ISBN) Aliakbarian, M. S ; Fanian, A ; Saleh, F. S ; Gulliver, T. A ; Sharif University of Technology
    2013
    Abstract
    Internet traffic classification is important in many aspects of network management such as data exploitation detection, malicious user identification, and restricting application traffic. Previously, features such as port and protocol numbers have been used to classify traffic, but these features can now be changed easily, making their use in traffic classification inadequate. Consequently, traffic classification based on machine learning (ML) is now employed. The number of features used in an ML algorithm has a significant impact on performance, in particular accuracy. In this paper, a minimum best feature set is chosen using a supervised method to obtain uncorrelated features. Outlier...