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Total 92 records

    Expression analysis of Wnt signaling pathway related lncRNAs in periodontitis: A pilot case-control study

    , Article Human Gene ; Volume 33 , 2022 ; 27730441 (ISSN) Ghafouri-Fard, S ; Dashti, S ; Gholami, L ; Badrlou, E ; Sadeghpour, S ; Hussen, B. M ; Hidayat, H. J ; Nazer, N ; Shadnoush, M ; Sayad, A ; Arefian, N ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    LncRNAs are involved in the modulation of several signaling pathways which have a crucial effect in the differentiation of periodontal ligament cells and the induction of cementum regeneration. Autophagy and Wnt signaling are two important pathways with a wide range of interrelationships associated with periodontitis. We chose four lncRNAs based on their potential interaction with these two pathways. We examined the expression of FOXD2-AS1, NNT-AS1, GAS8-AS1, and CCAT1 lncRNAs in tissues and blood specimens of patients with periodontitis and unaffected controls using qRT-PCR. Expression amounts of FOXD2-AS1 were lower in blood of cases compared with controls (relative expression (RE) = 0.08,... 

    Cost overrun risk assessment and prediction in construction projects: a bayesian network classifier approach

    , Article Buildings ; Volume 12, Issue 10 , 2022 ; 20755309 (ISSN) Ashtari, M. A ; Ansari, R ; Hassannayebi, E ; Jeong, J ; Sharif University of Technology
    MDPI  2022
    Abstract
    Cost overrun risks are declared to be dynamic and interdependent. Ignoring the relationship between cost overrun risks during the risk assessment process is one of the primary reasons construction projects go over budget. Conversely, recent studies have failed to account for potential interrelationships between risk factors in their machine learning (ML) models. Additionally, the presented ML models are not interpretable. Thus, this study contributes to the entire ML process using a Bayesian network (BN) classifier model by considering the possible interactions between predictors, which are cost overrun risks, to predict cost overrun and assess cost overrun risks. Furthermore, this study... 

    Diagnosis of brucellosis disease using data mining: A case study on patients of a hospital in Tehran

    , Article Journal of Microbiological Methods ; Volume 199 , 2022 ; 01677012 (ISSN) Sebt, M. V ; Jafari, S ; Khavaninzadeh, M ; Shavandi, A ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    Background: Brucellosis is a common zoonotic infection of humans from livestock. This bacterial infection is acquired from infected animals and their products. The pathogen of this disease is a genus of bacilli called Brucella, and no effective vaccine has been discovered yet for the prevention of human brucellosis. Objectives: The present study is mainly conducted to diagnose brucellosis accurately and timely, using Data Mining techniques. Based on the knowledge discovered with Data Mining and opinions of specialist physicians, this study aims to propose instructions for diagnosing brucellosis. Materials and methods: The dataset used in this study contains 340 samples and is extracted from... 

    An innovative inverse analysis based on the Bayesian inference for concrete material

    , Article Ultrasonics ; Volume 124 , 2022 ; 0041624X (ISSN) Nouri, A ; Toufigh, V ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    Nondestructive tests and evaluations are robust techniques for inspecting different attributes of concrete configuration. However, most nondestructive techniques focused on an aspect of concrete configuration based on comparison to other samples. In this paper, an innovative inverse analysis technique was developed to inspect different attributes of concrete configuration simultaneously. The methodology was based on the scattering feature of the ultrasonic waves during propagation in heterogeneous media. The transition matrix method was employed to determine the scattered wavefield. This method considers the shape of objects, unlike most other numerical methods. Furthermore, a novel... 

    A predictive multiphase model of silica aerogels for building envelope insulations

    , Article Computational Mechanics ; Volume 69, Issue 6 , 2022 , Pages 1457-1479 ; 01787675 (ISSN) Tan, J ; Maleki, P ; An, L ; Di Luigi, M ; Villa, U ; Zhou, C ; Ren, S ; Faghihi, D ; Sharif University of Technology
    Springer Science and Business Media Deutschland GmbH  2022
    Abstract
    This work develops a systematic uncertainty quantification framework to assess the reliability of prediction delivered by physics-based material models in the presence of incomplete measurement data and modeling error. The framework consists of global sensitivity analysis, Bayesian inference, and forward propagation of uncertainty through the computational model. The implementation of this framework on a new multiphase model of novel porous silica aerogel materials is demonstrated to predict the thermomechanical performances of a building envelope insulation component. The uncertainty analyses rely on sampling methods, including Markov-chain Monte Carlo and a mixed finite element solution of... 

    Improving joint sparse hyperspectral unmixing by simultaneously clustering pixels according to their mixtures

    , Article 47th IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2022, 23 May 2022 through 27 May 2022 ; Volume 2022-May , 2022 , Pages 5088-5092 ; 15206149 (ISSN); 9781665405409 (ISBN) Seyyedsalehi, S. F ; Rabiee, H. R ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2022
    Abstract
    In this paper we propose a novel hierarchical Bayesian model for sparse regression problem to use in semi-supervised hyperspectral unmixing which assumes the signal recorded in each hyperspectral pixel is a linear combination of members of the spectral library contaminated by an additive Gaussian noise. To effectively utilizing the spatial correlation between neighboring pixels during the unmixing process, we exploit a Markov random field to simultaneously group pixels to clusters which are associated to regions with homogeneous mixtures in a natural scene. We assume Sparse fractional abundances of members of a cluster to be generated from an exponential distribution with the same rate... 

    Correlation-augmented Naïve Bayes (CAN) Algorithm: A Novel Bayesian Method Adjusted for Direct Marketing

    , Article Applied Artificial Intelligence ; 2021 ; 08839514 (ISSN) Khalilpour Darzi, M. R ; Khedmati, M ; Akhavan Niaki, S. T ; Sharif University of Technology
    Taylor and Francis Ltd  2021
    Abstract
    Direct marketing identifies customers who buy, more probable, a specific product to reduce the cost and increase the response rate of a marketing campaign. The advancement of technology in the current era makes the data collection process easy. Hence, a large number of customer data can be stored in companies where they can be employed to solve the direct marketing problem. In this paper, a novel Bayesian method titled correlation-augment naïve Bayes (CAN) is proposed to improve the conventional naïve Bayes (NB) classifier. The performance of the proposed method in terms of the response rate is evaluated and compared to several well-known Bayesian networks and other well-known classifiers... 

    On Bayesian active vibration control of structures subjected to moving inertial loads

    , Article Engineering Structures ; Volume 239 , 2021 ; 01410296 (ISSN) Moradi, S ; Eftekhar Azam, S ; Mofid, M ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    This study introduces a novel Bayesian framework for online and real-time vibration control of beam type structures, which represent a comprehensive control system associated with input-state algorithms. Control design systems typically require knowledge of system states, which in structures are displacements and velocities at some degrees of freedom. Currently, full-field measurements of displacements and velocities in large structural systems are not feasible. Also, properties of the moving inertial loads as key parameters in control designs are assumed known; however, in practice, measuring their characteristics is a challenging issue. As a remedy, an observer is required to estimate... 

    Predicting the collisions of heavy vehicle drivers in iran by investigating the effective human factors

    , Article Journal of Advanced Transportation ; Volume 2021 , 2021 ; 01976729 (ISSN) Naderi, H ; Nassiri, H ; Zahedieh, F ; Sharif University of Technology
    Hindawi Limited  2021
    Abstract
    Traffic collisions are one of the most important challenges threatening the general health of the world. Iran's crash statistics demonstrate that approximately 16,500 people lose their lives every year due to road collisions. According to the traffic police of Iran, heavy vehicles (including trailers, trucks, and panel trucks) contributed to 20.5% of the fatal road traffic collisions in the year 2013. This highlights the need for devoting special attention to heavy vehicle drivers to further explore their driving characteristics. In this research, the effect of heavy vehicle drivers' behavior on at-fault collisions over three years has been investigated with an innovative approach of... 

    Persian sentiment analysis of an online store independent of pre-processing using convolutional neural network with fastText embeddings

    , Article PeerJ Computer Science ; Volume 7 , 2021 , Pages 1-22 ; 23765992 (ISSN) Shumaly, S ; Yazdinejad, M ; Guo, Y ; Sharif University of Technology
    PeerJ Inc  2021
    Abstract
    Sentiment analysis plays a key role in companies, especially stores, and increasing the accuracy in determining customers’ opinions about products assists to maintain their competitive conditions. We intend to analyze the users’ opinions on the website of the most immense online store in Iran; Digikala. However, the Persian language is unstructured which makes the pre-processing stage very difficult and it is the main problem of sentiment analysis in Persian. What exacerbates this problem is the lack of available libraries for Persian pre-processing, while most libraries focus on English. To tackle this, approximately 3 million reviews were gathered in Persian from the Digikala website using... 

    Online jointly estimation of hysteretic structures using the combination of central difference kalman filter and robbins–monro technique

    , Article JVC/Journal of Vibration and Control ; Volume 27, Issue 1-2 , 2021 , Pages 234-247 ; 10775463 (ISSN) Amini Tehrani, H ; Bakhshi, A ; Yang, T. T. Y ; Sharif University of Technology
    SAGE Publications Inc  2021
    Abstract
    Rapid assessment of structural safety and performance right after the occurrence of significant earthquake shaking is crucial for building owners and decision-makers to make informed risk management decisions. Hence, it is vital to develop online and pseudo-online health monitoring methods to quantify the health of the building right after significant earthquake shaking. Many Bayesian inference–based methods have been developed in the past which allow the users to estimate the unknown states and parameters. However, one of the most challenging part of the Bayesian inference–based methods is the determination of the parameter noise covariance matrix. It is especially difficult when the number... 

    Multi-site statistical downscaling of precipitation using generalized hierarchical linear models: a case study of the imperilled Lake Urmia basin

    , Article Hydrological Sciences Journal ; Volume 65, Issue 14 , 2020 , Pages 2466-2481 Abbasian, M. S ; Abrishamchi, A ; Najafi, M. R ; Moghim, S ; Sharif University of Technology
    Taylor and Francis Ltd  2020
    Abstract
    A downscaling model capable of explaining the temporal and spatial variability of regional hydroclimatic variables is essential for reliable climate change studies and impact assessments. This study proposes a novel statistical approach based on generalized hierarchical linear model (GHLM) to downscale precipitation from the outputs of general circulation models (GCMs) at multiple sites. GHLM partitions the total variance of precipitation into within- and between-site variability allowing for transferring information between sites to develop a regional downscaling model. The methodology is demonstrated by downscaling precipitation using the outputs of eight GCMs in Lake Urmia basin in... 

    A hybrid stochastic model based bayesian approach for long term energy demand managements

    , Article Energy Strategy Reviews ; Volume 28 , 2020 Ahmadi, S ; Fakehi, A. H ; vakili, A ; Haddadi, M ; Iranmanesh, H ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    In this study, a hybrid stochastic model (BScA model) using Bayesian approach and scenario analysis to forecast long term energy demand is developed. The main objective of this study is to design and develop a model for energy analysis in demand side and describe the energy saving and GHG reduction potential on the other. For this, total energy demand is selected as the response variable and primary energy production, population, GDP and natural gas and gasoline prices are chosen as covariates. Also, Political drivers, economic drivers, social-environmental and technological drivers are the key driving forces for scenario development. After interview and ranking the drivers, we have built... 

    Online jointly estimation of hysteretic structures using the combination of central difference Kalman filter and Robbins–Monro technique

    , Article JVC/Journal of Vibration and Control ; 2020 Amini Tehrani, H ; Bakhshi, A ; Yang, T. T. Y ; Sharif University of Technology
    SAGE Publications Inc  2020
    Abstract
    Rapid assessment of structural safety and performance right after the occurrence of significant earthquake shaking is crucial for building owners and decision-makers to make informed risk management decisions. Hence, it is vital to develop online and pseudo-online health monitoring methods to quantify the health of the building right after significant earthquake shaking. Many Bayesian inference–based methods have been developed in the past which allow the users to estimate the unknown states and parameters. However, one of the most challenging part of the Bayesian inference–based methods is the determination of the parameter noise covariance matrix. It is especially difficult when the number... 

    Improved K2 algorithm for Bayesian network structure learning

    , Article Engineering Applications of Artificial Intelligence ; Volume 91 , 2020 Behjati, S ; Beigy, H ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    In this paper, we study the problem of learning the structure of Bayesian networks from data, which takes a dataset and outputs a directed acyclic graph. This problem is known to be NP-hard. Almost most of the existing algorithms for structure learning can be classified into three categories: constraint-based, score-based, and hybrid methods. The K2 algorithm, as a score-based algorithm, takes a random order of variables as input and its efficiency is strongly dependent on this ordering. Incorrect order of variables can lead to learning an incorrect structure. Therefore, the main challenge of this algorithm is strongly dependency of output quality on the initial order of variables. The main... 

    Power allocation of sensor transmission for remote estimation over an unknown gilbert-elliott channel

    , Article 18th European Control Conference, ECC 2020, 12 May 2020 through 15 May 2020 ; 2020 , Pages 1461-1467 Farjam, T ; Fardno, F ; Charalambous, T ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2020
    Abstract
    In this paper, we consider the problem of scheduling the power of a sensor when transmitting over an unknown Gilbert-Elliott (GE) channel for remote state estimation. The sensor supports two power modes, namely low power and high power, which are to be selected for transmission over the channel in order to minimize a cost on the error covariance, while satisfying the energy constraints. The remote estimator provides error-free acknowledgement/negative-acknowledgement (ACK/NACK) messages to the sensor only when low power is utilized. We first consider the Partially Observable Markov Decision Process (POMDP) problem for the case of known GE channels and derive conditions for optimality of a... 

    Directional dependence of extreme metocean conditions for analysis and design of marine structures

    , Article Applied Ocean Research ; Volume 100 , 2020 Haghayeghi, Z. S ; Imani, H ; Karimirad, M ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    Marine structures are typically sensitive to the direction of wind and waves, especially in extreme metocean conditions. The extreme metocean conditions and their associated predicted directions are not easily reachable from traditional design methodologies. In this research, the most probable combinations of different extreme metocean conditions along with their associated direction are predicted for the HyWind Scotland wind farm, Scotland. To achieve this, the Hierarchical Bayesian Modeling approach is applied to define the Joint Probability Distribution Function (JPDF) of four combinations of metocean parameters, including wave direction, wind direction and wind-wave misalignment. The... 

    Wind speed sensor calibration in thermal power plant using Bayesian inference

    , Article Case Studies in Thermal Engineering ; Volume 19 , June , 2020 Mokhtari, A ; Ghodrat, M ; Javadpoor Langroodi, P ; Shahrian, A ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    Using natural draft dry air cooling systems in the power plant cycle is one of the proposed solutions for less water consumption. But the wind blowing will cause decreasement of cooling system performance in the power plants that work with the Rankin cycle. Therefore, it is important to know the right amount of wind speed to make the right decision to prevent reducing generating power or provide the right solution to improve the performance of the power plant cooling system. There are many methods of calibration of sensors in the world. But using optimization techniques or stochastic methods that do not require physical facilities and additional costs is almost a new approach. Therefore, in... 

    Time series forecasting of bitcoin price based on autoregressive integrated moving average and machine learning approaches

    , Article International Journal of Engineering, Transactions A: Basics ; Volume 33, Issue 7 , 2020 , Pages 1293-1303 Khedmati, M ; Seifi, F ; Azizi, M. J ; Sharif University of Technology
    Materials and Energy Research Center  2020
    Abstract
    Bitcoin as the current leader in cryptocurrencies is a new asset class receiving significant attention in the financial and investment community and presents an interesting time series prediction problem. In this paper, some forecasting models based on classical like ARIMA and machine learning approaches including Kriging, Artificial Neural Network (ANN), Bayesian method, Support Vector Machine (SVM) and Random Forest (RF) are proposed and analyzed for modelling and forecasting the Bitcoin price. While some of the proposed models are univariate, the other models are multivariate and as a result, the maximum, minimum and the opening daily price of Bitcoin are also used in these models. The... 

    An integrative Bayesian network approach to highlight key drivers in systemic lupus erythematosus

    , Article Arthritis Research and Therapy ; Volume 22, Issue 1 , June , 2020 Maleknia, S ; Salehi, Z ; Rezaei Tabar, V ; Sharifi Zarchi, A ; Kavousi, K ; Sharif University of Technology
    BioMed Central  2020
    Abstract
    Background: A comprehensive intuition of the systemic lupus erythematosus (SLE), as a complex and multifactorial disease, is a biological challenge. Dealing with this challenge needs employing sophisticated bioinformatics algorithms to discover the unknown aspects. This study aimed to underscore key molecular characteristics of SLE pathogenesis, which may serve as effective targets for therapeutic intervention. Methods: In the present study, the human peripheral blood mononuclear cell (PBMC) microarray datasets (n = 6), generated by three platforms, which included SLE patients (n = 220) and healthy control samples (n = 135) were collected. Across each platform, we integrated the datasets by...