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Predictive Process Control Using a Hierachical Method Based on Regression Analysis and Artificial Neural Networks (case study: Spray Drying in Tile Industry)
, M.Sc. Thesis Sharif University of Technology ; Mahlooji, Hashem (Supervisor)
Abstract
This is the first attempt at process modeling in terms of predictive control using a hierachical method based on regression analysis and artificial neural networks(ANNs).This hierachical use leads to the reliability improvement of neural model of process in prediction (extrapolation and interpolation) of process output. such an outlook makes it possible to predict the proper input settings which achieved a desired process output by designing various senarios for process set up. This approach was applied in Tile industry for spray dring process and in order to indicate the achieved improvement,three models:(i) regression model of process using multiple linear regression,(ii)Neural model of...
Algebraic bound for the phase–frequency response of the commande robuste d'ordre non-entier approximation of fractional differentiators and its applications in control systems analysis
, Article JVC/Journal of Vibration and Control ; 2021 ; 10775463 (ISSN) ; Tavazoei, M. S ; Sharif University of Technology
SAGE Publications Inc
2021
Abstract
This article deals with analyzing the phase–frequency response of commande robuste d'ordre non-entier approximations of fractional-order differentiators. More precisely, an algebraic tight upper bound is derived for the phase of the approximations obtained from the commande robuste d'ordre non-entier method. Then, some applications for this achievement are discussed in the viewpoint of control systems analysis. These applications include usefulness of the obtained upper bound in stability preservation analysis during the commande robuste d'ordre non-entier–based approximation process and applicability of such a bound in finding necessary or sufficient conditions for test of positive...
Algebraic bound for the phase–frequency response of the commande robuste d'ordre non-entier approximation of fractional differentiators and its applications in control systems analysis
, Article JVC/Journal of Vibration and Control ; Volume 28, Issue 9-10 , 2022 , Pages 1074-1085 ; 10775463 (ISSN) ; Tavazoei, M. S ; Sharif University of Technology
SAGE Publications Inc
2022
Abstract
This article deals with analyzing the phase–frequency response of commande robuste d'ordre non-entier approximations of fractional-order differentiators. More precisely, an algebraic tight upper bound is derived for the phase of the approximations obtained from the commande robuste d'ordre non-entier method. Then, some applications for this achievement are discussed in the viewpoint of control systems analysis. These applications include usefulness of the obtained upper bound in stability preservation analysis during the commande robuste d'ordre non-entier–based approximation process and applicability of such a bound in finding necessary or sufficient conditions for test of positive...
An enhanced neural network model for predictive control of granule quality characteristics
, Article Scientia Iranica ; Volume 18, Issue 3 E , 2011 , Pages 722-730 ; 10263098 (ISSN) ; Mahloojifl, H ; Kazemi, A ; Sharif University of Technology
2011
Abstract
An integrated approach is presented for predicting granule particle size using Partial Correlation (PC) analysis and Artificial Neural Networks (ANNs). In this approach, the proposed model is an abstract form from the ANN model, which intends to reduce model complexity via reducing the dimension of the input set and consequently improving the generalization capability of the model. This study involves comparing the capability of the proposed model in predicting granule particle size with those obtained from ANN and Multi Linear Regression models, with respect to some indicators. The numerical results confirm the superiority of the proposed model over the others in the prediction of granule...
Effect of reformer gas blending on homogeneous charge compression ignition combustion of primary reference fuels using multi zone model and semi detailed chemical-kinetic mechanism
, Article Applied Energy ; Volume 179 , 2016 , Pages 463-478 ; 03062619 (ISSN) ; KhoshbakhtiSaraya Saray, R ; Hosseini, V ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
This study mainly aims to investigate the effect of reformer gas (RG) addition on the performance of homogeneous charge compression ignition (HCCI) engines using a multi zone model. The developed model is validated using a wide range of experimental data of a cooperative fuel research engine. Blended fuels of isooctane and n-heptane, known as primary reference fuels, with different octane numbers are used as the main engine fuel. A semi detailed chemical-kinetic mechanism containing 101 species and 594 reactions is used to simulate the combustion of blended fuels. The study is performed with different percentages of RG (0–30%). The results show that RG reduces the rate of some H abstraction...
Investigation of the effect of reformer gas on PRFs HCCI combustion based on exergy analysis
, Article International Journal of Hydrogen Energy ; Volume 41, Issue 7 , 2016 , Pages 4278-4295 ; 03603199 (ISSN) ; Saray, R. K ; Hosseini, V ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
Lack of a direct method to control combustion timing is one of the main disadvantages of homogeneous charge compression ignition (HCCI) engines. Fuel blending, in which two fuels with different auto-ignition characteristics are blended, can be used to control combustion timing. Utilizing different additives is another method for HCCI combustion control. The aim of this research is investigation on the effect of reformer gas addition on the availability terms in HCCI engines fueled with primary reference fuels (PRFs). A multi zone model (MZM) coupled with a semi detailed chemical kinetics mechanism is used for calculation of different terms of exergy analysis. Heat and mass transfer between...
Conditions on Fractional-order LTI Systems to be Negative Imaginary
, M.Sc. Thesis Sharif University of Technology ; Tavazoei, Mohammad Saleh (Supervisor)
Abstract
In this thesis, we derive the analytic condition that linear time invariant fractional order system being positive real. Also, by inspiration of positive real condition, we derive the analytic condition for linear time invariant fractional order system that their imaginary part of frequency response being negative. Intended conditions for single input single output systems are derived in the form of necessary conditions in one way and derived in the form of sufficient conditions in another way. However, intended conditions in multiple input multiple output are just derived in the form of sufficient conditions. Furthermore, an upper band for phase of oustaloup approximation frequency response...
A hierarchical artificial neural network for transport energy demand forecast: Iran case study
, Article Neural Network World ; Volume 20, Issue 6 , 2010 , Pages 761-772 ; 12100552 (ISSN) ; Shakouri, H .G ; Menhaj, M. B ; Mehregan, M. R ; Neshat, N ; Asgharizadeh, E ; Taghizadeh, M. R ; Sharif University of Technology
2010
Abstract
This paper presents a neuro-based approach for annual transport energy demand forecasting by several socio-economic indicators. In order to analyze the influence of economic and social indicators on the transport energy demand, gross domestic product (GDP), population and total number of vehicles are selected. This approach is structured as a hierarchical artificial neural networks (ANNs) model based on the supervised multi-layer perceptron (MLP), trained with the back-propagation (BP) algorithm. This hierarchical ANNs model is designed properly. The input variables are transport energy demand in the last year, GDP, population and total number of vehicles. The output variable is the energy...
A Survey on Black Hole Physics
, M.Sc. Thesis Sharif University of Technology ; Bahmanabadi, Mahmoud (Supervisor) ; Sheikh-Jabbari, Mohammad Mahdi (Co-Supervisor)
Abstract
Black holes are a general set of solutions of Einstein’s general relativity. Their most important feature is the horizon, which is basically a region that separates the space-time into two causally disconnected regions. Studying the general features of black holes, classifying this family of solutions and studying the dynamics of particles and fields in the background of a given black hole are famous subjects in the field of classical black hole physics which are going to be covered in this thesis. By putting different conditions on the equations, we will get different solutions like Schwarzschild, Reissner-Nordstrom, Kerr, Kerr-Newman and etc, each of them having specific features. Then we...
A comparative study on car ownership modeling by applying fuzzy linear regression and artificial neural network - case study of Iran
, Article Summer Computer Simulation Conference, SCSC 2010 - Proceedings of the 2010 Summer Simulation Multiconference, SummerSim 2010, 12 July 2010 through 14 July 2010 ; Issue 1 BOOK , 2010 , Pages 25-31 ; 9781617387029 (ISBN) ; Rafiee, K ; Zohrevand, A.M ; Neshat, N ; Society for Modeling and Simulation International (SCS) ; Sharif University of Technology
2010
Abstract
This paper models car ownership in Iran based on the data in a period of years 1980 to 2007 by artificial neural network (ANN) and Fuzzy Linear Regression (FLR). The car ownership is mainly affected by purchasing power of the customers, social and demographic factors; the car ownership model has a multi variable form. To explain the effect of these factors, ANN and FLR models are applied. The major reason for applying fuzzy concept and ANN is to overcome the inter-correlation problem associated with the independent variables. In this study, average family size; total population; urban population; urbanization rate; gross national product per capita; gasoline price; total length of road are...
Dose-dependent effects of nanoscale graphene oxide on reproduction capability of mammals
, Article Carbon ; Volume 95 , December , 2015 , Pages 309-317 ; 00086223 (ISSN) ; Ghaderi, E ; Hashemi, E ; Akbari, E ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
In vivo dose-dependent effects of nanoscale graphene oxide (NGO) sheets on reproduction capability of Balb/C mice were investigated. Biodistribution study of the NGO sheets (intravenously injected into male mice at dose of ∼2000 μg/mL or 4 mg/kg of body weight) showed a high graphene uptake in testis. Hence, in vivo effects of the NGO sheets on important characteristics of spermatozoa (including their viability, morphology, kinetics, DNA damage and chromosomal aberration) were evaluated. Significant in vivo effects was found at the injected concentrations ≥200 μg/mL after (e.g., ∼45% reduction in sperm viability and motility at 2000 μg/mL). Observation of remarkable DNA fragmentations and...
Accelerated differentiation of neural stem cells into neurons on ginseng-reduced graphene oxide sheets
, Article Carbon ; Volume 66 , January , 2014 , Pages 395-406 ; Ghaderi, E ; Abouei, E ; Hatamie, S ; Ghasemi, E ; Sharif University of Technology
2014
Abstract
Asian red ginseng was used for green reduction of chemically exfoliated graphene oxide (GO) into reduced graphene oxide (rGO). The reduction level and electrical conductivity of the ginseng-rGO sheets were comparable to those of hydrazine-rGO ones. Reduction by ginseng resulted in repairing the sp 2 graphitic structure of the rGO, while hydrazine-rGO showed more defects and/or smaller aromatic domains. The ginseng-rGO sheets presented a better stability against aggregation than the hydrazine-rGO ones in an aqueous suspension. Whilst the hydrophobic hydrazine-rGO films exhibited no toxicity against human neural stem cells (hNSCs), the hydrophilic GO and ginseng-rGO films (as more...
Contested framings and policy controversies: Analysing biosafety policy-making in Iran
, Article Science and Public Policy ; Volume 40, Issue 5 , 2013 , Pages 616-627 ; 03023427 (ISSN) ; Millstone, E ; Sharif University of Technology
2013
Abstract
Vigorous debates have taken place within and between many countries about regulatory policy regimes covering the assessment and approval of genetically modified (GM) crops. In Iran, a very vigorous and hotly contested policy debate concerning legislation covering GM crops occurred between 2004 and 2009, but it was confined within government circles with almost no public discussion. This paper analyses the Iranian policy-making process in the period 2006-9. It explains how and why a stalemate arose in disputes between ministries and departments. The chosen analytical framework draws mainly on the regulation of technological risks and the analysis of public policy-making. It deploys the...
On the possible volumes of μ-way latin trades
, Article Aequationes Mathematicae ; Volume 63, Issue 3 , 2002 , Pages 303-320 ; 00019054 (ISSN) ; Billington, E. J ; Bryant, D. E ; Mahmoodian, E. S ; Sharif University of Technology
Birkhauser Verlag Basel
2002
Abstract
A μ-way latin trade of volume s is a set of μ partial latin rectangles (of inconsequential size) containing exactly the same s filled cells, such that if cell (i, j) is filled, it contains a different entry in each of the μ partial latin rectangles, and such that row i in each of the μ partial latin rectangles contains, set-wise, the same symbols and column j, likewise. In this paper we show that all μ-way latin trades with sufficiently large volumes exist, and state some theorems on the non-existence of μ-way latin trades of certain volumes. We also find the set of possible volumes (that is, the volume spectrum) of μ-way latin trades for μ = 4 and 5. (The case μ = 2 was dealt with by Fu,...
The three-way intersection problem for latin squares
, Article Discrete Mathematics ; Volume 243, Issue 1-3 , 2002 , Pages 1-19 ; 0012365X (ISSN) ; Billington, E. J ; Bryant, D. E ; Mahmoodian, E. S ; Sharif University of Technology
2002
Abstract
The set of integers k for which there exist three latin squares of order n having precisely k cells identical, with their remaining n2 -k cells different in all three latin squares, denoted by I3[n], is determined here for all orders n. In particular, it is shown that I3[n] = {0,.,n2 -15}U [n2 - 12,n2-9,n2], for n ≫8. ©2002 Eisevier Science B.V. All rights reserved
Integration of spatial fuzzy clustering with level set for segmentation of 2-D angiogram
, Article IECBES 2014, Conference Proceedings - 2014 IEEE Conference on Biomedical Engineering and Sciences: "Miri, Where Engineering in Medicine and Biology and Humanity Meet", 8 December 2014 through 10 December 2014 ; December , 2015 , Pages 309-314 ; 9781479940844 (ISBN) ; Zahedi, E ; Fatemizadeh, E ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
Coronary angiography is a vital instrument to detect the prevailing of vascular diseases, and accurate vascular segmentation acts a crucial role for proper quantitative analysis of the vascular tree morphological features. Level set methods are popular for segmenting the coronary arteries, but their performance is related to suitable start-up and optimum setting of regulating parameters, essentially done manually. This research presents a novel fuzzy level set procedure with the objective of segmentation of the coronary artery tree in 2-D X-ray angiography as automatically. It is clever to clearly develop from the early segmentation with spatial fuzzy grouping. The adjusting parameters of...
Deep relative attributes
, Article 13th Asian Conference on Computer Vision, ACCV 2016, 20 November 2016 through 24 November 2016 ; Volume 10115 LNCS , 2017 , Pages 118-133 ; 03029743 (ISSN); 9783319541921 (ISBN) ; Noury, E ; Adeli, E ; Sharif University of Technology
Springer Verlag
2017
Abstract
Visual attributes are great means of describing images or scenes, in a way both humans and computers understand. In order to establish a correspondence between images and to be able to compare the strength of each property between images, relative attributes were introduced. However, since their introduction, hand-crafted and engineered features were used to learn increasingly complex models for the problem of relative attributes. This limits the applicability of those methods for more realistic cases. We introduce a deep neural network architecture for the task of relative attribute prediction. A convolutional neural network (ConvNet) is adopted to learn the features by including an...
A public code for astrometric microlensing with contour integration
, Article Monthly Notices of the Royal Astronomical Society ; Volume 505, Issue 1 , 2021 , Pages 126-135 ; 00358711 (ISSN) ; Khalouei, E ; Bachelet, E ; Sharif University of Technology
Oxford University Press
2021
Abstract
We present the first public code for the calculation of the astrometric centroid shift occurring during microlensing events. The computation is based on the contour integration scheme and covers single and binary lensing of finite sources with arbitrary limb darkening profiles. This allows for general detailed investigations of the impact of finite source size in astrometric binary microlensing. The new code is embedded in version 3.0 of vbbinarylensing, which offers a powerful computational tool for extensive studies of microlensing data from current surveys and future space missions. © 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society
Toward electrically tunable, lithography-free, ultra-thin color filters covering the whole visible spectrum
, Article Scientific Reports ; Volume 8, Issue 1 , 2018 ; 20452322 (ISSN) ; Serebryannikov, A. E ; Khavasi, A ; Vandenbosch, G. A. E ; Ozbay, E ; Sharif University of Technology
Nature Publishing Group
2018
Abstract
The possibility of real-time tuning of optical devices has attracted a lot of interest over the last decade. At the same time, coming up with simple lithography-free structures has always been a challenge in the design of large-area compatible devices. In this work, we present the concept and the sample design of an electrically tunable, lithography-free, ultra-thin transmission-mode color filter, the spectrum of which continuously covers the whole visible region. A simple Metal-Insulator-Metal (MIM) cavity configuration is used. It is shown that using the electro-optic dielectric material of 4-dimethyl-amino-N-methyl-4-stilbazoliumtosylate (DAST) as the dielectric layer in this...
A novel method for modeling the magnetizing yoke
, Article Electromagnetics ; Volume 30, Issue 3 , 2010 , Pages 297-308 ; 02726343 (ISSN) ; Norouzi, E
2010
Abstract
Magnetic flux leakage is the most widely used method for oil and gas pipeline non destructive testing. The saturation level of the sample under test has a significant effect on its efficiency; therefore, the magnetizing yoke requires an elaborate design. The finite element method is the conventional approach used for this purpose, but it is very time consuming. In this article, a neuro-fuzzy method is presented to model the behavior of the magnetizing yoke. Modeling a few different designs with the finite element method and using the results for training the neuro-fuzzy model eradicates the necessity of modeling a huge number of designs with the finite element method. The acquired...