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    Erratum: LiFi grid: A machine learning approach to user-centric design (Applied Optics (2020) 59 (8895-8901) DOI: 10.1364/AO.396804)

    , Article Applied Optics ; Volume 59, Issue 31 , 2020 , Pages 9755- Pashazanoosi, M ; Nezamalhosseini, S. A ; Salehi, J. A ; Sharif University of Technology
    OSA - The Optical Society  2020
    Abstract
    This publisher’s note amends the author listing and affiliation section in Appl. Opt. 59, 8895 (2020). © 2020 Optical Society of America  

    Automatic learning of action priorities

    , Article Proceedings of the Eighth IASTED International Conference on Atificial Intelligence and Soft Computing, Marbella, 1 September 2004 through 3 September 2004 ; 2004 , Pages 255-259 ; 0889864586 (ISBN) Akramifar, S. A ; Ghassem Sani, G. R ; IASTED, TCAIETCSC ; Sharif University of Technology
    2004
    Abstract
    Traditional AI planners often suffer from their poor efficiency. There are many choice points in the planning process, but lack of information precludes proper decision. In this paper, we introduce a new method for adding automatic learning capability to a forward planning system. Our idea is based on a dynamic voting algorithm to choose the best action to proceed to the next state. In every planning cycle, applicable actions (i.e. those actions whose preconditions are satisfied in the current world state) vote to, and compete with each other. As a result of this voting, gradually more useful actions are chosen. This idea has been applied to the blocks world domain, and the preliminary... 

    Machine learning approach for carrier surface design in carrier-based dry powder inhalation

    , Article Computers and Chemical Engineering ; Volume 151 , 2021 ; 00981354 (ISSN) Kazemzadeh Farizhandi, A. A ; Alishiri, M ; Lau, R ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    In this study, a machine learning approach was applied to evaluate the impact of operating and design variables on dry powder inhalation efficiency. Emitted dose and fine particle fraction data were extracted from the literature for a variety of drug and carrier combinations. Carrier surface properties are obtained by image analysis of SEM images reported. Models combining artificial neural network and genetic algorithm were developed to determine the emitted dose and fine particle fraction. Design strategies for the carrier surface were also proposed to enhance the fine particle fractions. © 2021 Elsevier Ltd  

    Link prediction in multiplex online social networks

    , Article Royal Society Open Science ; Volume 4, Issue 2 , 2017 ; 20545703 (ISSN) Jalili, M ; Orouskhani, Y ; Asgari, M ; Alipourfard, N ; Perc, M ; Sharif University of Technology
    Royal Society  2017
    Abstract
    Online social networks play a major role in modern societies, and they have shaped the way social relationships evolve. Link prediction in social networks has many potential applications such as recommending new items to users, friendship suggestion and discovering spurious connections. Many real social networks evolve the connections in multiple layers (e.g. multiple social networking platforms). In this article, we study the link prediction problem in multiplex networks. As an example, we consider a multiplex network of Twitter (as a microblogging service) and Foursquare (as a location-based social network). We consider social networks of the same users in these two platforms and develop a... 

    Application of machine-learning models to estimate regional input coefficients and multipliers

    , Article Spatial Economic Analysis ; 2021 ; 17421772 (ISSN) Pakizeh, A. H ; Kashani, H ; Sharif University of Technology
    Routledge  2021
    Abstract
    Due to the unavailability of accurate data and the limitations of the existing methods, reliable input–output tables (IOTs) may not be available for all the regions in a country. This study proposes a novel approach to estimate the regional input coefficients. It harnesses the capabilities of machine-learning (ML) algorithms to estimate the regional input coefficients of one region based on the IOTs of multiple other regions for which reliable data are available. The application of three ML algorithms is investigated using data from Japan. The results highlight the superior performance of the ML models compared with location quotient models. © 2021 Regional Studies Association  

    The classification of heartbeats from two-channel ECG signals using layered hidden markov model

    , Article Frontiers in Biomedical Technologies ; Volume 9, Issue 1 , 2022 , Pages 59-67 ; 23455829 (ISSN) Sadoughi, A ; Shamsollahi, M. B ; Fatemizadeh, E ; Sharif University of Technology
    Tehran University of Medical Sciences  2022
    Abstract
    Purpose: Cardiac arrhythmia is one of the most common heart diseases that can have serious consequences. Thus, heartbeat arrhythmias classification is very important to help diagnose and treat. To develop the automatic classification of heartbeats, recent advances in signal processing can be employed. The Hidden Markov Model (HMM) is a powerful statistical tool with the ability to learn different dynamics of the real time-series such as cardiac signals. Materials and Methods: In this study, a hierarchy of HMMs named Layered HMM (LHMM) was presented to classify heartbeats from the two-channel electrocardiograms. For training in the first layer, the morphology of the heartbeats was used as... 

    Application of machine-learning models to estimate regional input coefficients and multipliers

    , Article Spatial Economic Analysis ; Volume 17, Issue 2 , 2022 , Pages 178-205 ; 17421772 (ISSN) Pakizeh, A. H ; Kashani, H ; Sharif University of Technology
    Routledge  2022
    Abstract
    Due to the unavailability of accurate data and the limitations of the existing methods, reliable input–output tables (IOTs) may not be available for all the regions in a country. This study proposes a novel approach to estimate the regional input coefficients. It harnesses the capabilities of machine-learning (ML) algorithms to estimate the regional input coefficients of one region based on the IOTs of multiple other regions for which reliable data are available. The application of three ML algorithms is investigated using data from Japan. The results highlight the superior performance of the ML models compared with location quotient models. © 2021 Regional Studies Association  

    Insights into TripAdvisor's online reviews: The case of Tehran's hotels

    , Article Tourism Management Perspectives ; Volume 34 , April , 2020 Khorsand, R ; Rafiee, M ; Kayvanfar, V ; Sharif University of Technology
    Elsevier B. V  2020
    Abstract
    User-generated data in TripAdvisor.com consists of considerable amount of useful information that can help managers to provide better services to their customers. This study aims to forecast a new user's rate to a hotel based on information of the hotel and user. To do so, all reviews on all hotels of Tehran on TripAdvisor.com as real data are selected and 8 different supervised machine learning models are applied to the data to select the best method including K-nearest neighbors (KNN), Naïve Bayes, decision tree, logistic regression, support vector machine, neural network, random forest, and gradient boosting. KNN algorithm which uses similarity and distance measures for classification is... 

    Real – time Transient Stability Assessment Using Adaboost Algorithm

    , M.Sc. Thesis Sharif University of Technology Sadeghi, Morteza (Author) ; Ranjbar, Ali Mohammad (Supervisor)
    Abstract
    Because of deregulation and economic issues, power systems operate closer to their stability limits than before. So, security assessment of power system has gained a lot of attention in power system studies. Transient stability and its real time assessment is a great concern in power system security. Among all different methods for transient stability assessment, Automatic Learning methods are used the most in real time assessment problems. These methods can provide fast assessment of transient stability, sensitivity analysis and means of control of the transient stability phenomena. In this paper Adaboost algorithm is used as a brand new method in transient stability assessment of a medium... 

    Compressed coded distributed computing

    , Article IEEE Transactions on Communications ; Volume 69, Issue 5 , 2021 , Pages 2773-2783 ; 00906778 (ISSN) Elkordy, A. R ; Li, S ; Maddah Ali, M. A ; Avestimehr, A. S ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2021
    Abstract
    Communication overhead is one of the major performance bottlenecks in large-scale distributed computing systems, in particular for machine learning applications. Conventionally, compression techniques are used to reduce the load of communication by combining intermediate results of the same computation task as much as possible. Recently, via the development of coded distributed computing (CDC), it has been shown that it is possible to enable coding opportunities across intermediate results of different computation tasks to further reduce the communication load. We propose a new scheme, named compressed coded distributed computing (in short, compressed CDC), which jointly exploits the above... 

    SELM: Software engineering of machine learning models

    , Article 20th International Conference on New Trends in Intelligent Software Methodologies, Tools and Techniques, SoMeT 2021, 21 September 2021 through 23 September 2021 ; Volume 337 , 2021 , Pages 48-54 ; 09226389 (ISSN); 9781643681948 (ISBN) Jafari, N ; Besharati, M. R ; Hourali, M ; Sharif University of Technology
    IOS Press BV  2021
    Abstract
    One of the pillars of any machine learning model is its concepts. Using software engineering, we can engineer these concepts and then develop and expand them. In this article, we present a SELM framework for Software Engineering of machine Learning Models. We then evaluate this framework through a case study. Using the SELM framework, we can improve a machine learning process efficiency and provide more accuracy in learning with less processing hardware resources and a smaller training dataset. This issue highlights the importance of an interdisciplinary approach to machine learning. Therefore, in this article, we have provided interdisciplinary teams' proposals for machine learning. © 2021... 

    Image Classification Using Sparse Representation

    , M.Sc. Thesis Sharif University of Technology Haghiri, Siyavash (Author) ; Rabiee, Hamid Reza (Supervisor)
    Abstract
    In this thesis, we have discussed image classification by sparse representation. Sparse representation is used in two different ways for image classification. The first goal of sparse representation is to make an efficient classifier, that can learn the subspace, in which the data lies. In this field we have surveyed various methods. We also proposed a method, called ”Locality Preserving Dictionary Learning” that works approximately better than state of the art similar methods, specially when training data is limited. We have reported the result of lassification on four datasets including MNIST, USPS, COIL2 and ISOLET. Another use of sparse representation, is to extract local features from... 

    Boosting for Transfer Learning in Brain-Computer Interface

    , M.Sc. Thesis Sharif University of Technology Tashakori, Arvin (Author) ; Shamsollahi, Mohammad Bagher (Supervisor)
    Abstract
    Transfer Learning is one of the most important fields in the Machine Learning area. Respect to the advances that we have seen in the Computer Science, especially in the Machine Learning area, we need a tool that can transfer learnings from different domains to each other. As data distribution varies, many statistical models require restructuring using new training data. In many applications, re-assembling training data and re-structuring models is inefficient and costly, so reducing the need for this practice seems appropriate. In these cases, knowledge transfer or learning transfer between domains may be desirable. For example, in the area of the B rain-Computer Interface, when it... 

    Analyzing IoT System Using Location-Base Data

    , M.Sc. Thesis Sharif University of Technology Ghandi Jalvani, Ali (Author) ; Gholampour, Iman (Supervisor)
    Abstract
    Nowadays, using different types of data has shown significant impacts on analyzing the related systems. Growth in data volume, systems complexity and existence of error and obscurity in collecting the data, increased the necessity of inventing new data analysis methods. Location-based data is an important data type for such analyses which are collected from sensors in different places. These data besides other official organization's information like municipality or Google … provide us a bulk volume of raw data. Such collections of raw data are mostly diverse, heterogeneous, bulk and outspread. Inspite of that, raw data with machine learning algorithms lead to considerable practical... 

    Learning-based power prediction for geo-distributed Data Centers: weather parameter analysis

    , Article Journal of Big Data ; Volume 7, Issue 1 , 2020 Taheri, S ; Goudarzi, M ; Yoshie, O ; Sharif University of Technology
    Springer  2020
    Abstract
    Nowadays, the fast rate of technological advances, such as cloud computing, has led to the rapid growth of the Data Center (DC) market as well as their power consumption. Therefore, DC power management has become increasingly important. While power forecasting can greatly help DC power management and reduce energy consumption and cost. Power forecasting predicts the potential energy failures or sudden fluctuations in power intake from utility grid. However, it is hard especially when variable renewable energies (RE) as well as free cooling such as air economizers are also used. Geo-distributed DCs face an even harder issue: since in addition to local conditions, the overall status of the... 

    Geo-spatiotemporal intelligence for smart agricultural and environmental eco-cyber-physical systems

    , Article Studies in Computational Intelligence ; Volume 911 , 2021 , Pages 471-491 ; 1860949X (ISSN) Majidi, B ; Hemmati, O ; Baniardalan, F ; Farahmand, H ; Hajitabar, A ; Sharafi, S ; Aghajani, K ; Esmaeili, A ; Manzuri, M. T ; Sharif University of Technology
    Springer Science and Business Media Deutschland GmbH  2021
    Abstract
    The rapid changes of the climate and the environment requires smart solutions and deployment of intelligent automated systems in agriculture and environment management. Rural communities should use artificial intelligence and big data analytics solutions in order to be able to mitigate the effects of climate change in the next decades. The Eco-Cyber-Physical-System (ecoCystem) is a combination of the living entities of the ecosystem in conjunction with the Cyber-Physical System (CPS) based components of the smart rural environments, interacting as a system. The goal of the ecoCystem is to use the power of artificial intelligence combined with Internet of Things (IOT) in order to provide... 

    Modal identification of concrete arch dam by fully automated operational modal identification

    , Article Structures ; Volume 32 , 2021 , Pages 228-236 ; 23520124 (ISSN) Mostafaei, H ; Ghamami, M ; Aghabozorgi, P ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    Modal identification is a type of system identification, which studies on the modal parameters of systems by using modal test. In the case of using operational or ambient modal analysis, there is no need to measure excitation, and the system output data are adequate for identification purposes. These modal parameters of system are of great importance from the engineering point of view particularly in the area of system identification, damage detection, and condition monitoring. In a fully-automated identification approach, the modal parameters are extracted without intervention of a specialized user. In this study, a Fully Automated Operational Modal Identification algorithm is developed to... 

    How resiliency and hope can predict stress of covid-19 by mediating role of spiritual well-being based on machine learning

    , Article Journal of Religion and Health ; Volume 60, Issue 4 , 2021 , Pages 2306-2321 ; 00224197 (ISSN) Nooripour, R ; Hosseinian, S ; Hussain, A. J ; Annabestani, M ; Maadal, A ; Radwin, L. E ; Hassani Abharian, P ; Pirkashani, N. G ; Khoshkonesh, A ; Sharif University of Technology
    Springer  2021
    Abstract
    Nowadays, artificial intelligence (AI) and machine learning (ML) are playing a tremendous role in all aspects of human life and they have the remarkable potential to solve many problems that classic sciences are unable to solve appropriately. Neuroscience and especially psychiatry is one of the most important fields that can use the potential of AI and ML. This study aims to develop an ML-based model to detect the relationship between resiliency and hope with the stress of COVID-19 by mediating the role of spiritual well-being. An online survey is conducted to assess the psychological responses of Iranian people during the Covid-19 outbreak in the period between March 15 and May 20, 2020, in... 

    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... 

    An ensemble-based predictive mutation testing approach that considers impact of unreached mutants

    , Article Software Testing Verification and Reliability ; Volume 31, Issue 7 , 2021 ; 09600833 (ISSN) Aghamohammadi, A ; Mirian Hosseinabadi, S. H ; Sharif University of Technology
    John Wiley and Sons Ltd  2021
    Abstract
    Predictive mutation testing (PMT) is a technique to predict whether a mutant is killed, using machine learning approaches. Researchers have proposed various methods for PMT over the years. However, the impact of unreached mutants on PMT is not fully addressed. A mutant is unreached if the statement on which the mutant is generated is not executed by any test cases. We aim at showing that unreached mutants can inflate PMT results. Moreover, we propose an alternative approach to PMT, suggesting a different interpretation for PMT. To this end, we replicated the previous PMT research. We empirically evaluated the suggested approach on 654 Java projects provided by prior literature. Our results...