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Total 122 records

    State of charge estimation for lithium-ion batteries based on square root sigma point Kalman filter considering temperature variations

    , Article IET Electrical Systems in Transportation ; Volume 12, Issue 3 , 2022 , Pages 165-180 ; 20429738 (ISSN) Mahboubi, D ; Jafari Gavzan, I ; Saidi, M. H ; Ahmadi, N ; Sharif University of Technology
    John Wiley and Sons Inc  2022
    Abstract
    The battery management system (BMS) in electric vehicles monitors the state of charge (SOC) and state of health (SOH) of lithium-ion battery by controlling transient parameters such as voltage, current, and temperature prevents the battery from operating outside the optimal operating range. The main feature of the battery management system is the correct estimation of the SOC in the broad range of vehicle navigation. In this paper, to estimate real-time of SOC in lithium-ion batteries and overcome faults of Extended Kalman Filter (EKF), the Square-Root Sigma Point Kalman Filter is applied on the basis of numerical approximations rather than analytical methods of EKF. For this purpose, the... 

    Vis-NIR hyperspectral imaging coupled with independent component analysis for saffron authentication

    , Article Food Chemistry ; Volume 393 , 2022 ; 03088146 (ISSN) Hashemi Nasab, F. S ; Parastar, H ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    In the present contribution, visible-near infrared hyperspectral imaging (Vis-NIR-HSI) combined with a novel chemometric approach based on mean-filed independent component analysis (MF-ICA) followed by multivariate classification techniques is proposed for saffron authentication and adulteration detection. First, MF-ICA was used to exploit pure spatial and spectral profiles of the components. Then, principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to find patterns of authentic samples based on their distribution maps. Then, detection of five common plant-derived adulterants of saffron including safflower, saffron style, calendula, rubia and turmeric were... 

    Evaluation of FT-IR spectroscopy combined with SIMCA and PLS‑DA for detection of adulterants in pistachio butter

    , Article Infrared Physics and Technology ; Volume 127 , 2022 ; 13504495 (ISSN) Khanban, F ; Bagheri Garmarudi, A ; Parastar, H ; Toth, G ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    This work scrutinized the adulteration of pistachio butter with three potential edible oils using Fourier transform infrared spectroscopy (FT-IR) and multivariate classification methods. Each of the classes, including non-adulterated samples and adulterated samples consisting of pistachio butter mixed with various concentrations of peanut oil, corn oil and sunflower oil, were classified. For this purpose, multivariate methods, including soft independent modeling of class analogy (SIMCA) and partial least squares discriminant analysis (PLS-DA), were applied to classify the FTIR data. After evaluating the model on unknown samples, the results indicated that PLS-DA was better than the SIMCA... 

    Time-varying dual accelerated gradient ascent: A fast network optimization algorithm

    , Article Journal of Parallel and Distributed Computing ; Volume 165 , 2022 , Pages 130-141 ; 07437315 (ISSN) Monifi, E ; Mahdavi Amiri, N ; Sharif University of Technology
    Academic Press Inc  2022
    Abstract
    We propose a time-varying dual accelerated gradient method for minimizing the average of n strongly convex and smooth functions over a time-varying network with n nodes. We prove that the time-varying dual accelerated gradient ascent method converges at an R-linear rate with the time to reach an ϵ-neighborhood of the solution being of O([Formula presented]ln⁡[Formula presented]), where c is a constant depending on the graph and objective function parameters and M is a constant depending on the initial values. We test the proposed method on two classes of problems: L2-regularized least squares and logistic classification problems. For each class, we generate 1000 problems and use the... 

    Perylene diimide-POSS network for semi selective solid-phase microextraction of lung cancer biomarkers in exhaled breath

    , Article Analytica Chimica Acta ; Volume 1198 , 2022 ; 00032670 (ISSN) Soufi, G ; Bagheri, H ; Yeganeh Rad, L ; Minaeian, S ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    Lung cancer (LC) is the leading cause of cancer mortality so, the analysis of exhaled human breath has great significance for early non-invasive diagnosis. Poor selectivity and strong humidity are two bottlenecks for the application of gas sensors to exhaled breath analysis. The development of novel extractive phases for the analysis of exhaled breath by chromatography is therefore a lucrative object. Polyhedral oligomeric silsesquioxanes (POSS) are among the 3D porous materials whose unique properties make them promising coatings for solid-phase microextraction (SPME). Selective enrichment of polar or nonpolar targets depends on the pore size and functional groups on the POSSs. Herein, we... 

    Application of mean-covariance regression methods for estimation of edp|im distributions for small record sets

    , Article Journal of Earthquake Engineering ; Volume 26, Issue 14 , 2022 , Pages 7276-7296 ; 13632469 (ISSN) Ghods, B ; Rofooei, F. R ; Sharif University of Technology
    Taylor and Francis Ltd  2022
    Abstract
    The performance of several regression methods is investigated to estimate the distribution of engineering demand parameters conditioned on intensity measures (EDP|IM) for small record sets. In particular, the performance of the multivariate ordinary least squares (OLS), a simultaneous mean-variance regression (MVR) done by a penalized weighted least-square loss function, and a mean-covariance/variance regression based on expectation maximization method (EM) are assessed. The efficiency of the introduced methods is compared with FEMA-P58 methodology. Performance assessment of EM and MVR methods shows that the overall increase in efficiency is about 25–45% for maximum inter-story drift ratios,... 

    Evaluation of partial least-squares regression with multivariate analytical figures of merit for determination of 10 pesticides in milk

    , Article International Journal of Environmental Analytical Chemistry ; Volume 102, Issue 8 , 2022 , Pages 1900-1910 ; 03067319 (ISSN) Koleini, F ; Balsini, P ; Parastar, H ; Sharif University of Technology
    Taylor and Francis Ltd  2022
    Abstract
    A multi-residue method using gas chromatography coupled with flame ionisation detector has been developed for simultaneous determination of 10 pesticides in milk. The methodology involved a sample clean-up procedure using ‘quick, easy, cheap, effective, rugged and safe’ followed by a preconcentration step based on dispersive liquid–liquid microextraction. In this regard, acetonitrile was added to the milk sample with specific pH and ionic strength, and the mixture was rigorously shaken. The extracts were centrifuged; then, the organic phase (acetonitrile) was transferred to a test tube and was mixed with deionised water. The mixture was sonicated and chloroform was added as an acceptor phase... 

    The impact of technological and social capabilities on innovation performance: a technological catch-up perspective

    , Article Technology in Society ; Volume 68 , 2022 ; 0160791X (ISSN) Fakhimi, M ; Miremadi, I ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    The literature on technological capabilities has highlighted the effects of innovation on economic growth. However, further analysis is required to determine how innovation factors affect the technological catch-up process outputs. The main purpose of the present study is therefore to determine the impacts of innovation-building factors (i.e., technological and social capabilities) on the innovation outputs. The role of market and innovation financing in technological catch-up has also been investigated. Partial least squares structural equation modeling has been employed to identify which factors have the most significant effects on this process. We have extracted twelve hypotheses from the... 

    Aortic dissection is determined by specific shape and hemodynamic interactions

    , Article Annals of Biomedical Engineering ; Volume 50, Issue 12 , 2022 , Pages 1771-1786 ; 00906964 (ISSN) Williams, J. G ; Marlevi, D ; Bruse, J. L ; Nezami, F. R ; Moradi, H ; Fortunato, R. N ; Maiti, S ; Billaud, M ; Edelman, E. R ; Gleason, T. G ; Sharif University of Technology
    Springer  2022
    Abstract
    The aim of this study was to determine whether specific three-dimensional aortic shape features, extracted via statistical shape analysis (SSA), correlate with the development of thoracic ascending aortic dissection (TAAD) risk and associated aortic hemodynamics. Thirty-one patients followed prospectively with ascending thoracic aortic aneurysm (ATAA), who either did (12 patients) or did not (19 patients) develop TAAD, were included in the study, with aortic arch geometries extracted from computed tomographic angiography (CTA) imaging. Arch geometries were analyzed with SSA, and unsupervised and supervised (linked to dissection outcome) shape features were extracted with principal component... 

    Chemometrics-assisted isotope ratio fingerprinting based on gas chromatography/combustion/isotope ratio mass spectrometry for saffron authentication

    , Article Journal of Chromatography A ; Volume 1657 , 2021 ; 00219673 (ISSN) Ghiasi, S ; Parastar, H ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    In the present contribution, the capability of isotopic ratio mass spectrometry (IRMS) for saffron authentication and detection of four common plant-derived adulterants (marigold flower, safflower, rubia, and saffron style) was investigated. For this purpose, 62 authentic saffron samples were analyzed by elemental analyzer-IRMS (EA-IRMS) and gas chromatography-combustion-IRMS (GC-C-IRMS). In this regard, EA-IRMS and GC-C-IRMS isotope fingerprints of carbon-13 and nitrogen-15 isotopes of saffron components were provided and then analyzed by chemometric methods. Principal component analysis (PCA) showed two different behaviors regarding two main regions. Then, a representative saffron sample... 

    Application of mean-covariance regression methods for estimation of edp|im distributions for small record sets

    , Article Journal of Earthquake Engineering ; 2021 ; 13632469 (ISSN) Ghods, B ; Rahimzadeh Rofooei, F ; Sharif University of Technology
    Taylor and Francis Ltd  2021
    Abstract
    The performance of several regression methods is investigated to estimate the distribution of engineering demand parameters conditioned on intensity measures (EDP|IM) for small record sets. In particular, the performance of the multivariate ordinary least squares (OLS), a simultaneous mean-variance regression (MVR) done by a penalized weighted least-square loss function, and a mean-covariance/variance regression based on expectation maximization method (EM) are assessed. The efficiency of the introduced methods is compared with FEMA-P58 methodology. Performance assessment of EM and MVR methods shows that the overall increase in efficiency is about 25–45% for maximum inter-story drift ratios,... 

    Efficient closed-form solution for 3-d hybrid localization in multistatic radars

    , Article IEEE Transactions on Aerospace and Electronic Systems ; Volume 57, Issue 6 , 2021 , Pages 3886-3895 ; 00189251 (ISSN) Kazemi, S. A. R ; Amiri, R ; Behnia, F ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2021
    Abstract
    In this article, an algebraic solution for localizing a moving target using a nonstationary multistatic radar system is proposed. By utilizing the quadruple hybrid measurement set, which consists of time delay, Doppler shift, angle of arrival, and angle rate measurements, the proposed method can estimate the target position and velocity vectors via a simple one-stage weighted least squares estimator without the need for introduction of the nuisance parameters, which enables us to locate the target with the minimum number of antennas. The proposed estimator takes the uncertainty concerned with the position and velocity of the antennas in its design. The proposed estimator is shown to be... 

    Providing Multicolor Plasmonic Patterns with Au@Ag Core-Shell Nanostructures for Visual Discrimination of Biogenic Amines

    , Article ACS Applied Materials and Interfaces ; Volume 13, Issue 17 , 2021 , Pages 20865-20874 ; 19448244 (ISSN) Orouji, A ; Ghasemi, F ; Bigdeli, A ; Hormozi Nezhad, M. R ; Sharif University of Technology
    American Chemical Society  2021
    Abstract
    Biogenic amines (BAs) are known as substantial indicators of the quality and safety of food. Developing rapid and visual detection methods capable of simultaneously monitoring BAs is highly desired due to their harmful effects on human health. In the present study, we have designed a multicolor sensor array consisting of two types of gold nanostructures (i.e., gold nanorods (AuNRs) and gold nanospheres (AuNSs)) for the discrimination and determination of critical BAs (i.e., spermine (SM), tryptamine (TT), ethylenediamine (EA), tyramine (TR), spermidine (SD), and histamine (HT)). The design principle of the probe was based on the metallization of silver ions on the surface of AuNRs and AuNSs... 

    Nondestructive nitrogen content estimation in tomato plant leaves by Vis-NIR hyperspectral imaging and regression data models

    , Article Applied Optics ; Volume 60, Issue 30 , 2021 , Pages 9560-9569 ; 1559128X (ISSN) Pourdarbani, R ; Sabzi, S ; Rohban, M. H ; García Mateos, G ; Arribas, J. I ; Sharif University of Technology
    The Optical Society  2021
    Abstract
    The present study aims to estimate nitrogen (N) content in tomato (Solanum lycopersicum L.) plant leaves using optimal hyperspectral imaging data by means of computational intelligence [artificial neural networks and the differential evolution algorithm (ANN-DE), partial least squares regression (PLSR), and convolutional neural network (CNN) regression] to detect potential plant stress to nutrients at early stages. First, pots containing control and treated tomato plants were prepared; three treatments (categories or classes) consisted in the application of an overdose of 30%, 60%, and 90% nitrogen fertilizer, called N-30%, N-60%, N-90%, respectively. Tomato plant leaves were then randomly... 

    Radial basis function-artificial neural network (RBF-ANN) for simultaneous fluorescent determination of cysteine enantiomers in mixtures

    , Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 261 , 2021 ; 13861425 (ISSN) Safarnejad, A ; Reza Hormozi Nezhad, M ; Abdollahi, H ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    The determination of chiral compounds is critically important in chemical and pharmaceutical sciences. Cysteine amino acid is one of the important chiral compounds where each enantiomer (L and D) has different effects on fundamental physiological processes. The unique optical properties of nanoparticles make them a suitable probe for the determination of different analytes. In this work, the water-soluble thioglycolic acid (TGA)-capped cadmium-telluride (CdTe) quantum dots (QDs) were applied as optical nanoprobe for the simultaneous determination of cysteine enantiomers. The difference in the kinetics of the interactions between L- and D-cysteine with CdTe QDs is used for multivariate... 

    Comparison of near-infrared (NIR) and mid-infrared (MIR) spectroscopy based on chemometrics for saffron authentication and adulteration detection

    , Article Food Chemistry ; Volume 344 , 2021 ; 03088146 (ISSN) Amirvaresi, A ; Nikounezhad, N ; Amirahmadi, M ; Daraei, B ; Parastar, H ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    In this work, the potential of near-infrared (NIR) and mid-infrared (MIR) spectroscopy along with chemometrics was investigated for authentication and adulteration detection of Iranian saffron samples. First, authentication of one-hundred saffron samples was examined by principal component analysis (PCA). The results showed the NIR spectroscopy can better predict the origin of samples than the MIR. Next, partial least squares-discriminant analysis (PLS-DA) was developed to detect four common plant-derived adulterants (i.e., saffron style, calendula, safflower, and rubia). In all cases, PLS-DA classification figures of merit in terms of sensitivity, specificity, error rate and accuracy were... 

    Plastic temperature-dependent constitutive modeling of pure aluminum diaphragms at large strains by using bulge test

    , Article Journal of Materials Research and Technology ; Volume 11 , 2021 , Pages 412-427 ; 22387854 (ISSN) Ashrafian, M. M ; Hosseini Kordkheili, A ; Sharif University of Technology
    Elsevier Editora Ltda  2021
    Abstract
    A plastic temperature-dependent constitutive model is developed for 0.05 mm thickness pure aluminum diaphragms at large strains by using bulge test method. Rupture strain of the material is recorded below two percent according to tensile tests. In order to achieve the material behavior at larger strains, an own bulge test apparatus is used to extract equi-biaxial stress-strain curves at different temperatures, i.e. from room to 150 °C. Effective stress-strain behavior is then computed via a transformation scheme using the plastic work definition as well as the room temperature uniaxial stress-strain curve. It is illustrated that the Johnson-Cook constitutive model is not able to capture this... 

    Combining multivariate image analysis with high-performance thin-layer chromatography for development of a reliable tool for saffron authentication and adulteration detection

    , Article Journal of Chromatography A ; Volume 1628 , 2020 Amirvaresi, A ; Rashidi, M ; Kamyar, M ; Amirahmadi, M ; Daraei, B ; Parastar, H ; Sharif University of Technology
    Elsevier B.V  2020
    Abstract
    In this work, high-performance thin-layer chromatography (HPTLC) coupled with multivariate image analysis (MIA) is proposed as a fast and reliable tool for authentication and adulteration detection of Iranian saffron samples based on their HPTLC fingerprints. At first, the secondary metabolites of saffron were extracted using ultrasonic-assisted solvent extraction (UASE) which was optimized using central composite design (CCD). Next, the RGB coordinates of HPTLC images were used for estimation of saffron origin based on principal component analysis (PCA). The PCA scores plot showed that saffron samples were clustered into two clear-cut groups which was 92% matched with the geographical... 

    Improved least squares approaches for differential received signal strength-based localization with unknown transmit power

    , Article Wireless Personal Communications ; Volume 110, Issue 3 , 2020 , Pages 1373-1401 Danaee, M. R ; Behnia, F ; Sharif University of Technology
    Springer  2020
    Abstract
    In this paper we consider the problem of improving unknown node localization by using differential received signal strength (DRSS). Many existing localization approaches, especially those using the least squares methods, either ignore nonlinear constraint among model parameters or utilize them inefficiently. In this paper, we develop four DRSS-based localization methods by utilizing different combinations of covariance and weight matrices. Each method constructs a two-stage procedure. During the first stage, an initial coarse position estimate is obtained. The second stage results the refined localization by accounting for nonlinear dependency among estimator variables. The proper choice... 

    Structural damage detection using principal component analysis of frequency response function data

    , Article Structural Control and Health Monitoring ; Volume 27, Issue 7 , 2020 Esfandiari, A ; Nabiyan, M. S ; Rahimzadeh Rofooei, F ; Sharif University of Technology
    John Wiley and Sons Ltd  2020
    Abstract
    In this paper, a new sensitivity-based model updating method is presented based on the changes of principal components (PCs) of frequency response function (FRF). Structural damage estimation, identification of damage location and severity, is conducted by an innovative sensitivity relation. The sensitivity relation is derived by incorporating PC analysis (PCA) data obtained from the incomplete measured structural responses in a mathematical formulation and is then solved by the least square method. In order to demonstrate the performance of the proposed method, it is applied to a truss and a frame model. The results prove the ability of the method as a robust damage detection algorithm in...