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    Neutron-Gamma Discrimination by a Dual Detector

    , M.Sc. Thesis Sharif University of Technology Aghabozorgi Sahaf, Sajjad (Author) ; Vosoughi, Naser (Supervisor)
    Abstract
    This thesis examines various approaches of digital and analog methods of neutron - gamma discrimination. The analog detector used in this research is a type of 2inch and NE213 liquid scintillator. The applied analog discrimination method is the zero-crossing time and the Neutron Source is AmBe. In digital discrimination, the simulated pulses are generated and used for the experiment of the research. The method used to separate the data are two partitional clustering methods, namely FCM and K-Medoids. The FCM and K-Medoids are two data mining approaches in which the input data are grouped in two or more clusters based on their similarities. The merit of this approach is that this algorithms... 

    Active constrained fuzzy clustering: A multiple kernels learning approach

    , Article Pattern Recognition ; Volume 48, Issue 3 , March , 2015 , Pages 953-967 ; 00313203 (ISSN) Abin, A. A ; Beigy, H ; Sharif University of Technology
    Elsevier Ltd  2015
    Abstract
    In this paper, we address the problem of constrained clustering along with active selection of clustering constraints in a unified framework. To this aim, we extend the improved possibilistic c-Means algorithm (IPCM) with multiple kernels learning setting under supervision of side information. By incorporating multiple kernels, the limitation of improved possibilistic c-means to spherical clusters is addressed by mapping non-linear separable data to appropriate feature space. The proposed method is immune to inefficient kernels or irrelevant features by automatically adjusting the weight of kernels. Moreover, extending IPCM to incorporate constraints, its strong robustness and fast... 

    A clustering fuzzification algorithm based on ALM

    , Article Fuzzy Sets and Systems ; Volume 389 , 2020 , Pages 93-113 Javadian, M ; Malekzadeh, A ; Heydari, G ; Bagheri Shouraki, S ; Sharif University of Technology
    Elsevier B.V  2020
    Abstract
    In this paper, we propose a fuzzification method for clusters produced from a clustering process, based on Active Learning Method (ALM). ALM is a soft computing methodology which is based on a hypothesis claiming that human brain interprets information in pattern-like images. The proposed fuzzification method is applicable to all non-fuzzy clustering algorithms as a post process. The most outstanding advantage of this method is the ability to determine the membership degrees of each data to all clusters based on the density and shape of the clusters. It is worth mentioning that for existing fuzzy clustering algorithms such as FCM the membership degree is usually determined as a function of... 

    A fuzzy clustering algorithm for finding arbitrary shaped clusters

    , Article 6th IEEE/ACS International Conference on Computer Systems and Applications, AICCSA 2008, Doha, 31 March 2008 through 4 April 2008 ; 2008 , Pages 559-566 ; 9781424419685 (ISBN) Soleymani Baghshah, M ; Bagheri Shouraki, S ; Sharif University of Technology
    2008
    Abstract
    Until now, many algorithms have been introduced for finding arbitrary shaped clusters, but none of these algorithms is able to identify all sorts of cluster shapes and structures that are encountered in practice. Furthermore, the time complexity of the existing algorithms is usually high and applying them on large dataseis is time-consuming. In this paper, a novel fast clustering algorithm is proposed. This algorithm distinguishes clusters of different shapes using a twostage clustering approach. In the first stage, the data points are grouped into a relatively large number of fuzzy ellipsoidal sub-clusters. Then, connections between sub-clusters are established according to the Bhatiacharya... 

    Design of a gain-scheduling anti-swing controller for tower cranes using fuzzy clustering techniques

    , Article CIMCA 2006: International Conference on Computational Intelligence for Modelling, Control and Automation, Jointly with IAWTIC 2006: International Conference on Intelligent Agents Web Technologies and International Commerce, Sydney, NSW, 28 November 2006 through 1 December 2006 ; 2006 ; 0769527310 (ISBN); 9780769527314 (ISBN) Sadati, N ; Hooshmand, A ; Sharif University of Technology
    IEEE Computer Society  2006
    Abstract
    The main objective of this paper is to design a fast,non-expensive and practical controller for towercranes. The controllers are designed to transfer theloads from point to point, as fast as possible, and at thesame time the load swing is kept small during thetransfer process. Moreover, variations of the systemparameters such as cable length are taken intoconsideration. It is shown how the state feedbackcontrollers along with the gain scheduling could beused for a time varying linear model with varyingparameters. For this reason, linear controllers aredesigned for a number of operating points, where theirparameters are interpolated for conditions in between.In this way, a globally nonlinear... 

    Spiking neuro-fuzzy clustering system and its memristor crossbar based implementation

    , Article Microelectronics Journal ; Vol. 45, issue. 11 , 2014 , pp. 1450-1462 ; ISSN: 00262692 Bavandpour, M ; Bagheri-Shouraki, S ; Soleimani, H ; Ahmadi, A ; Linares-Barranco, B ; Sharif University of Technology
    Abstract
    This study proposes a spiking neuro-fuzzy clustering system based on a novel spike encoding scheme and a compatible learning algorithm. In this system, we utilize an analog to binary encoding scheme that properly maps the concept of "distance" in multi-dimensional analog spaces to the concept of "dissimilarity " of binary bits in the equivalent binary spaces. When this scheme is combined with a novel binary to spike encoding scheme and a proper learning algorithm is applied, a powerful clustering algorithm is produced. This algorithm creates flexible fuzzy clusters in its analog input space and modifies their shapes to different convex shapes during the learning process. This system has... 

    A multispectral image segmentation method using size-weighted fuzzy clustering and membership connectedness

    , Article IEEE Geoscience and Remote Sensing Letters ; Volume 7, Issue 3 , March , 2010 , Pages 520-524 ; 1545598X (ISSN) Hasanzadeh, M ; Kasaei, S ; Sharif University of Technology
    2010
    Abstract
    Clustering-based image segmentation is a well-known multispectral image segmentation method. However, as it inherently does not account for the spatial relation among image pixels, it often results in inhomogeneous segmented regions. The recently proposed membership-connectedness (MC)-based segmentation method considers the local and global spatial relations besides the fuzzy clustering stage to improve segmentation accuracy. However, the inherent spatial and intraclass redundancies in multispectral images might decrease the accuracy and efficiency of the method. This letter addresses these two problems and proposes a segmentation method that is based on the MC method, watershed transform,... 

    New Hybrid Approaches Information Clustering Based on FCM Clustering and Optimization CFA

    , M.Sc. Thesis Sharif University of Technology Farzin Far, Zohreh (Author) ; Ramezanian, Rasoul (Supervisor)
    Abstract
    Clustering algorithms are developed to provide general attitudes on database, recognizing latent structures and their more effective accessibility. Recently, broad studies are conducted on clustering since it is recognized as an important tool to explore and analyze data. Clustering is a fundamental learning operation without monitoring in data exploration which divides data into groups of objects so that objects in one group have the most similarity to each other and lowest similarity to objects in other groups. Some clustering algorithms such fuzzy clustering model (FCM) are widely used in clustering problem solution although this technique addresses local optimized searches. Additionally,... 

    F.C.A: designing a fuzzy clustering algorithm for haplotype assembly

    , Article IEEE International Conference on Fuzzy Systems, 20 August 2009 through 24 August 2009 ; 2009 , Pages 1741-1744 ; 10987584 (ISSN) ; 9781424435975 (ISBN) Moeinzadeh, M. H ; Asgarian, E ; Noori, M. M ; Sadeghi, M ; Sharifian R., S ; Sharif University of Technology
    Abstract
    Reconstructing haplotype in MEC (Minimum Error Correction) model is an important clustering problem which focuses on inferring two haplotypes from SNP fragments (Single Nucleotide Polymorphism) containing gaps and errors. Mutated form of human genome is responsible for genetic diseases which mostly occur in SNP sites. In this paper, a fuzzy clustering approach is performed for haplotype reconstruction or haplotype assembly from a given sample Single Nucleotide Polymorphism (SNP). In the best previous approach based on reconstruction rate (Wang 2007[2]), all SNP-fragments are considered with equal values. In our proposed method the value of the fragments are based on the degree of membership... 

    Modified maximum entropy fuzzy data association filter

    , Article Journal of Dynamic Systems, Measurement and Control, Transactions of the ASME ; Volume 132, Issue 2 , 2010 , Pages 1-9 ; 00220434 (ISSN) Dehghani Tafti, A ; Sadati, N ; Sharif University of Technology
    2010
    Abstract
    The problem of fuzzy data association for target tracking in a cluttered environment is discussed in this paper. In data association filters based on fuzzy clustering, the association probabilities of tracking filters are reconstructed by utilizing the fuzzy membership degree of the measurement belonging to the target. Clearly in these filters, the fuzzy clustering method has an important role; better approach causes better precision in target tracking. Recently, by using the information theory, the maximum entropy fuzzy data association filter (MEF-DAF), as a fast and efficient algorithm, is introduced in literature. In this paper, by modification of a fuzzy clustering objective function,... 

    A comparison of performance of artificial intelligence methods in prediction of dry sliding wear behavior

    , Article International Journal of Advanced Manufacturing Technology ; Volume 84, Issue 9-12 , 2016 , Pages 1981-1994 ; 02683768 (ISSN) Alambeigi, F ; Khadem, S. M ; Khorsand, H ; Mirza Seied Hasan, E ; Sharif University of Technology
    Springer-Verlag London Ltd 
    Abstract
    Developing a computational model for studying tribological performance is essential for computing accurate life cycle of various materials. Caused by the existence of complicated and nonlinear interactions between material surfaces, exact modeling of wear behavior is very difficult. Artificial intelligence (AI) can be used in distinguishing similar patterns in experimental data and predictive modeling of a certain material’s wear behavior. In this paper, artificial neural networks (ANNs) approach, adaptive neural-based fuzzy inference system (ANFIS) technique, and fuzzy clustering method (FCM) are used to develop a simple, accurate, and applicable model for predicting the wear behavior of... 

    Multispectral Fuzzy Image Segmentation

    , Ph.D. Dissertation Sharif University of Technology Hasanzadeh, Maryam (Author) ; Kasaei, Shohreh (Supervisor)
    Abstract
    Image segmentation is middle and an important task in image analysis and machine vision applications. The output images of imaging systems are often fuzzy because of noise, limitation in spatial and temporal resolution, blurring and intensity inhomogeneity in the objects. The goal of this thesis is exploring the fuzzy methods in multispectral image segmentation and proposing a new one to solve some of the recent difficulties and problems. The difficulties and problems such as simultaneous utilization of spatial and spectral information, necessity for dimension reduction, spatial and spectral and intra-cluster image information redundancy, existence of regions with widely varying size,... 

    Developing Hierarchical Active Learning Method Framework for Complex Systems Analysis

    , Ph.D. Dissertation Sharif University of Technology Javadian, Mohammad (Author) ; Bagheri Shouraki, Saeed (Supervisor)
    Abstract
    In recent decades, the science of studying complex systems has started to evolve and mature. Complex systems research is becoming ever more important in both the natural and social sciences. The study of mathematical complex system models is used for many scientific questions poorly suited to the traditional mechanistic conception provided by science. Examples of complex systems are Earth's global climate, organisms, the human brain, social organization, an ecosystem, a living cell, and ultimately the entire universe. Motivations for studying complex and self-organized systems can be somewhat divided between science, or attempts to understand such systems, and engineering, or attempts to... 

    Reliability evaluation of a composite power system containing wind and solar generation

    , Article Proceedings of the 2013 IEEE 7th International Power Engineering and Optimization Conference, PEOCO 2013 ; 2013 , p. 483-488 ; ISBN: 9781470000000 Ghaedi, A ; Abbaspour, A ; Fotuhi-Firuzabad, M ; Moeini-Aghtaie, M ; Othman, M ; Sharif University of Technology
    Abstract
    Variability and uncertainty of wind and photovoltaic (PV) generations greatly influence technical and financial aspects of power systems. This paper examines the potential impacts of large-scale wind and PV farms on reliability level of composite generation and transmission systems. At first, reliability models of renewable-based units are developed. In these models, both component failure rates and uncertainty nature of renewable resources are taken into account. Using the proposed technique, the multi-state analytical models of a wind farm placed in Manjil and a PV farm placed in Jask both in Iran are extracted. Then, reliability studies of high renewable-energies penetrated power system... 

    Reliability evaluation of a composite power system containing wind and solar generation

    , Article Proceedings of the 2013 IEEE 7th International Power Engineering and Optimization Conference, PEOCO 2013 2013, Article , Pages 483-488 ; number 6564597 , 2013 , Pages 483-488 ; 9781467350730 (ISBN) Ghaedi, A ; Abbaspour, A ; Fotuhi Firuzabad, M ; Moeini Aghtaie, M ; Othman, M ; Sharif University of Technology
    2013
    Abstract
    Variability and uncertainty of wind and photovoltaic (PV) generations greatly influence technical and financial aspects of power systems. This paper examines the potential impacts of large-scale wind and PV farms on reliability level of composite generation and transmission systems. At first, reliability models of renewable-based units are developed. In these models, both component failure rates and uncertainty nature of renewable resources are taken into account. Using the proposed technique, the multi-state analytical models of a wind farm placed in Manjil and a PV farm placed in Jask both in Iran are extracted. Then, reliability studies of high renewable-energies penetrated power system... 

    A novel density-based fuzzy clustering algorithm for low dimensional feature space

    , Article Fuzzy Sets and Systems ; 2016 ; 01650114 (ISSN) Javadian, M ; Bagheri Shouraki, S ; Sheikhpour Kourabbaslou, S ; Sharif University of Technology
    Elsevier B.V  2016
    Abstract
    In this paper, we propose a novel density-based fuzzy clustering algorithm based on Active Learning Method (ALM), which is a methodology of soft computing inspired by some hypotheses claiming that human brain interprets information in pattern-like images rather than numerical quantities. The proposed clustering algorithm, Fuzzy Unsupervised Active Learning Method (FUALM), is performed in two main phases. First, each data point spreads in the feature space just like an ink drop that spreads on a sheet of paper. As a result of this process, densely connected ink patterns are formed that represent clusters. In the second phase, a fuzzifying process is applied in order to summarize the effects... 

    A novel density-based fuzzy clustering algorithm for low dimensional feature space

    , Article Fuzzy Sets and Systems ; Volume 318 , 2017 , Pages 34-55 ; 01650114 (ISSN) Javadian, M ; Bagheri Shouraki, S ; Sheikhpour Kourabbaslou, S ; Sharif University of Technology
    Abstract
    In this paper, we propose a novel density-based fuzzy clustering algorithm based on Active Learning Method (ALM), which is a methodology of soft computing inspired by some hypotheses claiming that human brain interprets information in pattern-like images rather than numerical quantities. The proposed clustering algorithm, Fuzzy Unsupervised Active Learning Method (FUALM), is performed in two main phases. First, each data point spreads in the feature space just like an ink drop that spreads on a sheet of paper. As a result of this process, densely connected ink patterns are formed that represent clusters. In the second phase, a fuzzifying process is applied in order to summarize the effects... 

    Human–robot facial expression reciprocal interaction platform: case studies on children with autism

    , Article International Journal of Social Robotics ; Volume 10, Issue 2 , April , 2018 , Pages 179-198 ; 18754791 (ISSN) Ghorbandaei Pour, A ; Taheri, A ; Alemi, M ; Meghdari, A ; Sharif University of Technology
    Springer Netherlands  2018
    Abstract
    Reciprocal interaction and facial expression are some of the most interesting topics in the fields of social and cognitive robotics. On the other hand, children with autism show a particular interest toward robots, and facial expression recognition can improve these children’s social interaction abilities in real life. In this research, a robotic platform has been developed for reciprocal interaction consisting of two main phases, namely as Non-structured and Structured interaction modes. In the Non-structured interaction mode, a vision system recognizes the facial expressions of the user through a fuzzy clustering method. The interaction decision-making unit is combined with a fuzzy finite... 

    A POS-based fuzzy word clustering algorithm for continuous speech recognition systems

    , Article 2007 9th International Symposium on Signal Processing and its Applications, ISSPA 2007, Sharjah, 12 February 2007 through 15 February 2007 ; 2007 ; 1424407796 (ISBN); 9781424407798 (ISBN) Momtazi, S ; Sameti, H ; Bahrani, M ; Hafezi, N ; Sharif University of Technology
    2007
    Abstract
    Using word base n-gram language models in continuous speech recognition systems is so prevalent. For using this type of language models, we should extract them from large corpora. Since Persian corpora are not rich, therefore the extracted language models are not credible. For this reason, most researchers extract class n-grams instead of finding word n-grams. In this research a new idea for fuzzy word clustering is represented that each word can be assigned to more that one class. The Fuzzy c-mean algorithm is used for our clustering method and we have examined its various parameters of it. Finally, this algorithm was applied on 20000 most frequent Persian words extracted from "Persian Text...