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    Reservoir optimization in recurrent neural networks using properties of kronecker product

    , Article Logic Journal of the IGPL ; Volume 18, Issue 5 , 2009 , Pages 670-685 ; 13670751 (ISSN) Ajdari Rad, A ; Hasler, M ; Jalili, M ; Sharif University of Technology
    2009
    Abstract
    Recurrent neural networks based on reservoir computing are increasingly being used in many applications. Optimization of the topological structure of the reservoir and the internal connection weights for a given task is one of the most important problems in reservoir computing. In this paper, considering the fact that one can construct a large matrix using Kronecker products of several small-size matrices, we propose a method to optimize the reservoir. Having a small number of parameters to optimize, a gradient based algorithm is applied to optimize parameters, and consequently the reservoir. In addition to reducing the number of parameters for optimization, potentially, the method is able... 

    Predication of prosodic data in Persian text-to-speech systems using recurrent neural network

    , Article Electronics Letters ; Volume 39, Issue 25 , 2003 , Pages 1868-1869 ; 00135194 (ISSN) Farrokhi, A ; Ghaemmaghami, S ; Sharif University of Technology
    2003
    Abstract
    A simplified four-layer recurrent neural network (RNN) based architecture is introduced to generate prosodic information for improving naturalness in Persian text-to-speech (TTS) systems. The proposed RNN uses the first two layers at word level and the last two layers at syllable level to provide the TTS system with major prosodic parameters, including: pitch contour, energy contour, length of syllables, length and onset time of vowels, and duration of pauses. The experimental results show improvement of accuracy in prediction of prosodic parameters, as compared to similar prosody generation systems of higher complexity  

    Identification and Control of a Nuclear Reactor Core (VVER) Using Recurrent Neural Networks and Fuzzy Systems

    , Article IEEE Transactions on Nuclear Science ; Volume 50, Issue 1 , 2003 , Pages 159-174 ; 00189499 (ISSN) Boroushaki, M ; Ghofrani, M. B ; Lucas, C ; Yazdanpanah, M. J ; Sharif University of Technology
    2003
    Abstract
    Improving the methods of identification and control of nuclear power reactors core is an important area in nuclear engineering. Controlling the nuclear reactor core during load following operation encounters some difficulties in control of core thermal power while considering the core limitations in local power peaking and safety margins. In this paper, a nuclear power reactor core (VVER) is identified using a multi nonlinear autoregressive with exogenous inputs (NARX) structure, including neural networks with different time steps and a heuristic compound learning method, consisting of off- and on-line batch learning. An intelligent nuclear reactor core controller, is designed which... 

    An intelligent nuclear reactor core controller for load following operations, using recurrent neural networks and fuzzy systems

    , Article Annals of Nuclear Energy ; Volume 30, Issue 1 , 2003 , Pages 63-80 ; 03064549 (ISSN) Boroushaki, M ; Ghofrani, M. B ; Lucas, C ; Yazdanpanah, M. J ; Sharif University of Technology
    2003
    Abstract
    In the last decade, the intelligent control community has paid great attention to the topic of intelligent control systems for nuclear plants (core, steam generator). Papers mostly used approximate and simple mathematical SISO (single-input-single-output) model of nuclear plants for testing and/or tuning of the control systems. They also tried to generalize theses models to a real MIMO (multi-input-multi-output) plant, while nuclear plants are typically of complex nonlinear and multivariable nature with high interactions between their state variables and therefore, many of these proposed intelligent control systems are not appropriate for real cases. In this paper, we designed an on-line... 

    Predicting the empirical distribution of video quality scores using recurrent neural networks

    , Article International Journal of Engineering, Transactions B: Applications ; Volume 33, Issue 5 , 2020 , Pages 984-991 Otroshi Shahreza, H ; Amini, A ; Behroozi, H ; Sharif University of Technology
    Materials and Energy Research Center  2020
    Abstract
    Video quality assessment is a crucial routine in the broadcasting industry. Due to the duration and the excessive number of video files, a computer-based video quality assessment mechanism is the only solution. While it is common to measure the quality of a video file at the compression stage by comparing it against the raw data, at later stages, no reference video is available for comparison. Therefore, a noreference (Blind) video quality assessment (NR-VQA) technique is essential. The current NR-VQA methods predict only the mean opinion score (MOS) and do not provide further information about the distribution of people score. However, this distribution is informative for the evaluation of... 

    Separation of nonlinearly mixed sources using end-to-end deep neural networks

    , Article IEEE Signal Processing Letters ; Volume 27 , 2020 , Pages 101-105 Zamani, H ; Razavikia, S ; Otroshi-Shahreza, H ; Amini, A ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2020
    Abstract
    In this letter, we consider the problem of blind source separation under certain nonlinear mixing conditions using a deep learning approach. Conventionally, the separation of sources within linear mixtures is achieved by applying the independence property of the sources. In the nonlinear regime, however, this property is no longer sufficient. In this letter, we consider nonlinear mixing operators where the non-linearity could be fairly approximated using a Taylor series. Next, for solving the nonlinear BSS problem, we design an end-to-end recurrent neural network (RNN) that learns the inverse of the system, and ultimately separates the sources. For training the RNN, we employ a set of... 

    A combined wavelet transform and recurrent neural networks scheme for identification of hydrocarbon reservoir systems from well testing signals

    , Article Journal of Energy Resources Technology, Transactions of the ASME ; Volume 143, Issue 1 , 2021 ; 01950738 (ISSN) Moghimihanjani, M ; Vaferi, B ; Sharif University of Technology
    American Society of Mechanical Engineers (ASME)  2021
    Abstract
    Oil and gas are likely the most important sources for producing heat and energy in both domestic and industrial applications. Hydrocarbon reservoirs that contain these fuels are required to be characterized to exploit the maximum amount of their fluids. Well testing analysis is a valuable tool for the characterization of hydrocarbon reservoirs. Handling and analysis of long-term and noise-contaminated well testing signals using the traditional methods is a challenging task. Therefore, in this study, a novel paradigm that combines wavelet transform (WT) and recurrent neural networks (RNN) is proposed for analyzing the long-term well testing signals. The WT not only reduces the dimension of... 

    Development of Pavement Performance Prediction Models Based on the Assumptions of Availablity and Ubavailabilty of Accurate Data

    , M.Sc. Thesis Sharif University of Technology Ziyadi, Mojtaba (Author) ; Tabatabaei, Nader (Supervisor) ; Shafahi, Yusof (Supervisor)
    Abstract
    Accurate prediction of pavement performance is essential to a pavement infrastructure management system. Selection of the prediction model is based on the extent of available data, assumptions used in performance modeling, ease of use and management purposes. Therefore, two methods were proposed in this thesis based on the assumptions of availability and unavailibility of accurate data. The first method presents a two-stage model to classify and accurately predict the performance of a pavement infrastructure system. Sections with similar characteristics are classified into groups using a support vector classifier (SVC). Then, a recurrent neural network (RNN) is utilized to predict... 

    Path Planning for a Mobil Robot in an Unkonwn Environment By Recurrent Neural Networks

    , M.Sc. Thesis Sharif University of Technology Hassanzadeh, Mohammad (Author) ; Zarei, Alireza (Supervisor) ; Malek, Alaeddin (Supervisor)
    Abstract
    Path planning of a robot inside an environment with obstacles is to determine an appropriate path for moving from an initial point to a destination without colliding the obstacles. The main considerations in selecting such a path are its length and simplicity in terms of links or turn angles. In this paper, we study this problem for a point robot in the plane and our goal is to minimize the path length. We solve this problem by converting it to an optimization problem and solving the resulted optimization problem by a recurrent neural network. According to the implementation results, the obtained path is a proper approximation of the minimum length path, especially when obstacles are not too... 

    Using Echo State Networks for Modeling and Prediction of Drought Based on Remote Sensing Data

    , M.Sc. Thesis Sharif University of Technology Mohammadinejad, Amir (Author) ; Jalili, Mahdi (Supervisor)
    Abstract
    Iran is regarded as a dry land and has suffered from extreme to severe drought conditions in recent years. Drought – which is mainly caused by shortage in rainfall – affects the normal life in Iran. Development of tools for effectively monitoring and predicting drought intensity might help the policy makers to reduce the vulnerability of the areas affected by drought. In this thesis, we showed that the intensity of drought can be predicted using satellite imagery data and recurrent neural networks. To this end, the standardized precipitation index (SPI) was chosen as an index for drought and normalized deviation of vegetation index (NDVI) as a remote sensing measure extracted from NOAA-AVHRR... 

    Language Modeling Using Recurrent Neural Networks

    , M.Sc. Thesis Sharif University of Technology Rahimi, Adel (Author) ; Sameti, Hossein (Supervisor)
    Abstract
    This thesis examines the differences and the similarities between the two famous RNN blocks the Long Short Term Memory and the Gated Recurrent Unit. It measure different aspects such as computational complexity, Word Error Rate, and subjective human evaluation in the task of text generation.In the computational complexity experiment results show that the LSTM takes more time to compute, in comparison to the GRU. Moving on into the next experiment the GRU slightly outperforms the LSTM in terms of WER but the perplexity for the language models tested was the same. This shows that slight differences in the perplexity does not drastically change the WER. Having said, the results suggest that the... 

    State Space Reconstruction with Application in Revealing the Nonlinear Dynamics of Brain

    , M.Sc. Thesis Sharif University of Technology Heydari, Mohammad Reza (Author) ; Tavazoei, Mohammad Saleh (Supervisor) ; Ghazazideh, Ali (Co-Supervisor)
    Abstract
    Learning is an essential mechanism for the survival of living things. There are different types of learning, and value learning is among the most important types. A child learns that water resolves the thirst need by repeatedly experiencing this situation. Eventually, the value of water, which has been valueless before that, increases gradually in his mind. How this concept is encoded in the brain? previous works reveal the role of different neurons and regions that are relevant to value learning. However, population analysis and dynamic modeling are less considered. Moreover, the links between different brain regions are unknown.Finding the relationship between two relevant regions of the... 

    Hierarchical Classification of Variable Stars Using Deep Convolutional and Recurrent Neural Networks

    , M.Sc. Thesis Sharif University of Technology Abdollahi, Mahdi (Author) ; Rahvar, Sohrab (Supervisor) ; Raeisi, Sadegh (Supervisor)
    Abstract
    The importance of using a fast and automatic method to classify variable stars for large amounts of data is undeniable. There have been many attempts for classifying variable stars by traditional algorithms, which require long pre-processing time. In recent years, neural networks as classifiers have come to notice. This thesis proposes the Hierarchical Classification technique, which contains several models with the same network structure. Our pre-processing method produces input data by using light curves and the period. We use OGLE-IV variable stars database to train and test the performance of Convolutional Neural Networks based on the Hierarchical Classification technique. We see that... 

    Temporal Action Localization Using Recurrent Neural Networks

    , M.Sc. Thesis Sharif University of Technology Keshvari Khojasteh, Hassan (Author) ; Behroozi, Hamid (Supervisor) ; Mohammadzadeh, Narjesolhoda (Co-Supervisor)
    Abstract
    Action recognition is one of the important tasks in computer vision that detects the action label in videos that contain only one action. In recent years, action recognition has attracted much attention and researchers have tried to solve it by different approaches.Action recognition by itself does not have many applications in the real world because videos are untrimmed and do not contain only one action. So Temporal Action Localization(TAL) task in which we want to predict the start and end time of each action in addition to the action label has a lot of applications in the real world and for this reason, TAL is a hot research topic. But due to its complexity, researchers have not reached... 

    Indoor Positioning Based on Wi-Fi and Bluetooth Low Energy

    , M.Sc. Thesis Sharif University of Technology Beigi Harchekani, Karamat (Author) ; Shah Mansouri, Hamed (Supervisor)
    Abstract
    Indoor positioning plays a pivotal role in a wide range of applications, from smart homes to industrial automation. In this thesis, we propose a comprehensive approach for accurate positioning in indoor environments through the integration of existing Wi-Fi and Bluetooth Low Energy (BLE) devices. The proposed algorithm involves acquiring the received signal strength indicator (RSSI) data from these devices and capturing the complex interactions between RSSI and positions. To enhance the accuracy of the collected data, we first use a Kalman filter for denoising RSSI values, then categorize them into distinct classes using the K-nearest neighbor (KNN) algorithm. Incorporating the filtered... 

    Removing undesired effects of mass/inertia on transparency using artificial neural networks in a haptic mechanism

    , Article ICCAS 2010 - International Conference on Control, Automation and Systems, 27 October 2010 through 30 October 2010, Gyeonggi-do ; 2010 , Pages 156-161 ; 9781424474530 (ISBN) Khodabakhsh, M ; Boroushaki, M ; Vossoughi, G ; Sharif University of Technology
    2010
    Abstract
    In this paper, Artificial Neural Networks (ANN) has been used to identify the dynamics of robots used in haptic and master slave devices in order to improve transparency. In haptic and master slave devices, transparency depends on some factors such as robot's mass and inertia, gravitational forces and friction [1]. In such systems, mass and inertia of the robot has an undesirable effect on the system outputs, which should be neutralized for improved transparency. The main purpose of this paper introducting a method to neutralize the undesirable effects of mass and inertia of the robot. A recurrent multilayer perceptron (RMLP) is used in a way that the inputs and outputs of the neural network... 

    Axial offset control of PWR nuclear reactor core using intelligent techniques

    , Article Nuclear Engineering and Design ; Volume 227, Issue 3 , 2004 , Pages 285-300 ; 00295493 (ISSN) Boroushaki, M ; Ghofrani, M. B ; Lucas, C ; Yazdanpanah, M. J ; Sadati, N ; Sharif University of Technology
    2004
    Abstract
    Improved load following capability is one of the main technical performances of advanced PWR (APWR). Controlling the nuclear reactor core during load following operation encounters some difficulties. These difficulties mainly arise from nuclear reactor core limitations in local power peaking, while the core is subject to large and sharp variation of local power density during transients. Axial offset (AO) is the parameter usually used to represent of core power peaking, in form of a practical parameter. This paper, proposes a new intelligent approach to AO control of PWR nuclear reactors core during load following operation. This method uses a neural network model of the core to predict the... 

    Energy consumption forecasting of Iran using recurrent neural networks

    , Article Energy Sources, Part B: Economics, Planning and Policy ; Volume 6, Issue 4 , 2011 , Pages 339-347 ; 15567249 (ISSN) Avami, A ; Boroushaki, M ; Sharif University of Technology
    2011
    Abstract
    In this paper, a recurrent neural network model is developed in order to forecast the energy consumption as a complex nonlinear function of gross domestic product (GDP) and population in Iran. This intelligent model is trained by total energy consumption data as output and the population and GDP as inputs during 1976-2001, while 5 annual data points of the following years (2002-2006) are used to validate the model. It can describe time dependencies efficiently and the convergence rate is much faster. This model forecasts the trend of energy consumption annually. Simulation results show that this model can predict energy consumption in Iran with acceptable accuracy. It is expected that this... 

    No-Reference video quality assessment using recurrent neural networks

    , Article 5th Iranian Conference on Signal Processing and Intelligent Systems, ICSPIS 2019, 18 December 2019 through 19 December 2019 ; 2019 ; 9781728153506 (ISBN) Otroshi Shahreza, H ; Amini, A ; Behroozi, H ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Abstract
    The quality assessment is a vital routine in videorelated industries such as broadcast service providers. Due to the duration and the excessive number of the video files, case by case assessment of the files by operators is no longer feasible. Therefore, a computer-based video quality assessment mechanism is the only solution. While it is common to measure the quality of a video file at the compression stage by comparing it against the raw data, at later stages no reference video is available for comparison. Therefore, a no-reference (Blind) video quality assessment (NR-VQA) technique is essential. The common NRVQA methods learn a quality metric based on a number of features extracted from... 

    Continuous-Time relationship prediction in dynamic heterogeneous information networks

    , Article ACM Transactions on Knowledge Discovery from Data ; Volume 13, Issue 4 , 2019 ; 15564681 (ISSN) Sajadmanesh, S ; Bazargani, S ; Zhang, J ; Rabiee, H. R ; Sharif University of Technology
    Association for Computing Machinery  2019
    Abstract
    Online social networks, World Wide Web, media, and technological networks, and other types of so-called information networks are ubiquitous nowadays. These information networks are inherently heterogeneous and dynamic. They are heterogeneous as they consist of multi-Typed objects and relations, and they are dynamic as they are constantly evolving over time. One of the challenging issues in such heterogeneous and dynamic environments is to forecast those relationships in the network that will appear in the future. In this article, we try to solve the problem of continuous-Time relationship prediction in dynamic and heterogeneous information networks. This implies predicting the time it takes...