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Institution

Amirkabir University of Technology

EducationTehran, Iran
About: Amirkabir University of Technology is a education organization based out in Tehran, Iran. It is known for research contribution in the topics: Nonlinear system & Finite element method. The organization has 15254 authors who have published 31165 publications receiving 487551 citations. The organization is also known as: Tehran Polytechnic & Tehran Polytechnic University.


Papers
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Journal ArticleDOI
TL;DR: The iterative solution of fully fuzzy linear systems which is called FFLS is discussed and iterative techniques such as Richardson, Jacobi,Jacobi overrelaxation (JOR), Gauss–Seidel, successive overrel relaxation (SOR), accelerated overrelAXation (AOR), symmetric and unsymmetric SOR (SSOR and USSOR) and extrapolated modified Aitken (EMA) are proposed for solving it.
Abstract: This paper mainly intends to discuss the iterative solution of fully fuzzy linear systems which we call FFLS. We employ Dubois and Prade’s approximate arithmetic operators on LR fuzzy numbers for finding a positive fuzzy vector x ˜ which satisfies A ∼ x ˜ = b ∼ , where A ∼ and b ∼ are a fuzzy matrix and a fuzzy vector, respectively. Please note that the positivity assumption is not so restrictive in applied problems. We transform FFLS and propose iterative techniques such as Richardson, Jacobi, Jacobi overrelaxation (JOR), Gauss–Seidel, successive overrelaxation (SOR), accelerated overrelaxation (AOR), symmetric and unsymmetric SOR (SSOR and USSOR) and extrapolated modified Aitken (EMA) for solving FFLS. In addition, the methods of Newton, quasi-Newton and conjugate gradient are proposed from nonlinear programming for solving a fully fuzzy linear system. Various numerical examples are also given to show the efficiency of the proposed schemes.

143 citations

Journal ArticleDOI
TL;DR: A hybrid intelligent model for stock exchange index prediction using a combination of data preprocessing methods, genetic algorithms and Levenberg-Marquardt (LM) algorithm for learning feed forward neural networks is proposed.
Abstract: Artificial Intelligence models (AI) which computerize human reasoning has found a challenging test bed for various paradigms in many areas including financial time series prediction. Extensive researches have resulted in numerous financial applications using AI models. Since stock investment is a major investment activity, Lack of accurate information and comprehensive knowledge would result in some certain loss of investment. Hence, stock market prediction has always been a subject of interest for most investors and professional analysts. Stock market prediction is a challenging problem because uncertainties are always involved in the market movements. This paper proposes a hybrid intelligent model for stock exchange index prediction. The proposed model is a combination of data preprocessing methods, genetic algorithms and Levenberg-Marquardt (LM) algorithm for learning feed forward neural networks. Actually it evolves neural network initial weights for tuning with LM algorithm by using genetic algorithm. We also use data pre-processing methods such as data transformation and input variables selection for improving the accuracy of the model. The capability of the proposed method is tested by applying it for predicting some stock exchange indices used in the literature. The results show that the proposed approach is able to cope with the fluctuations of stock market values and also yields good prediction accuracy. So it can be used to model complex relationships between inputs and outputs or to find data patterns while performing financial prediction.

143 citations

Journal ArticleDOI
TL;DR: In this paper, a homotopy perturbation method (HPM) is proposed to solve non-linear systems of second-order boundary value problems, which yields solutions in convergent series forms with easily computable terms.
Abstract: A homotopy perturbation method (HPM) is proposed to solve non-linear systems of second-order boundary value problems. HPM yields solutions in convergent series forms with easily computable terms, and in some cases, yields exact solutions in one iteration. Moreover, this technique does not require any discretization, linearization or small perturbations and therefore reduces the numerical computations a lot. Some numerical results are also given to demonstrate the validity and applicability of the presented technique. The results reveal that the method is very effective, straightforward and simple.

143 citations

Journal ArticleDOI
01 Apr 2015
TL;DR: The results show that BNNMAS significantly performs accurate and reliable, so it can be considered as a suitable tool for predicting stock price specially in a long term periods.
Abstract: Creating an intelligent system that can accurately predict stock price in a robust way has always been a subject of great interest for many investors and financial analysts. Predicting future trends of financial markets is more remarkable these days especially after the recent global financial crisis. So traders who access to a powerful engine for extracting helpful information throw raw data can meet the success. In this paper we propose a new intelligent model in a multi-agent framework called bat-neural network multi-agent system (BNNMAS) to predict stock price. The model performs in a four layer multi-agent framework to predict eight years of DAX stock price in quarterly periods. The capability of BNNMAS is evaluated by applying both on fundamental and technical DAX stock price data and comparing the outcomes with the results of other methods such as genetic algorithm neural network (GANN) and some standard models like generalized regression neural network (GRNN), etc. The model tested for predicting DAX stock price a period of time that global financial crisis was faced to economics. The results show that BNNMAS significantly performs accurate and reliable, so it can be considered as a suitable tool for predicting stock price specially in a long term periods.

143 citations

Journal ArticleDOI
TL;DR: In this paper, a polyisocyanate-functionalized graphene oxide (PI-GO) was synthesized at various functionalization reaction times of 24, 48 and 72 h. The results obtained from X-ray diffraction analysis also revealed that the interlayer distance of the GO increased after modification.

142 citations


Authors

Showing all 15352 results

NameH-indexPapersCitations
Ali Mohammadi106114954596
Mehdi Dehghan8387529225
Morteza Mahmoudi8333426229
Gaurav Sharma82124431482
Vladimir A. Rakov6745914918
Mohammad Reza Ganjali65103925238
Bahram Ramezanzadeh6235212946
Muhammad Sahimi6248117334
Niyaz Mohammad Mahmoodi6121810080
Amir A. Zadpoor6129411653
Mohammad Hossein Ahmadi6047711659
Goodarz Ahmadi6077817735
Maryam Kavousi5925822009
Keith W. Hipel5854314045
Danial Jahed Armaghani552128400
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
202346
2022216
20212,493
20202,359
20192,368
20182,266