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Gaining Competitive Advantages on E-CRM in Financial Institutions in Iran Through B2B Model
, M.Sc. Thesis Sharif University of Technology ; Miremadi, Alireza (Supervisor) ; Amini Lari, Mansour (Supervisor)
Abstract
Due to violent and ferocious competition and global changes of new trends, directions and new ways of doing business, financial institutions grapple with new challenges and opportunities in today business. The advancement in technology, information and communication has forced banks and financial institutions into hard competition. In this new era technology, people as the customer are the elements on which the banks are concentrating them to manage customer relationship. In this complicated situation, Electronic customer relationship management (E-CRM) is seen applicatory and beneficial solution to improve customers‟ service, develop a profitable and long term relationship and retain...
The Impact of eCRM on Loyalty and Retention of Customers in Iranian Mobile Telecommunication Sector
, M.Sc. Thesis Sharif University of Technology ; Miremadi, Alireza (Supervisor) ; Amini Lari, Mansour (Co-Advisor)
Abstract
Today, almost all the Iranian mobile telecommunication companies should rely heavily on customer loyalty and customer retention as essential and vital tools to provide a competitive advantage in this competitive telecommunication world by offering value and upper hand service with respect to the existing demand in the Iranian market, hence these determinants arise the need for studying eCRM, Loyalty and Retention in order to achieve customer satisfaction in the Iranian mobile telecommunication field. 400 customers who use the Iranian mobile telecom operators’ services (Hamrah-e Avval, Irancell, and Talia) have been asked as respondents in this research. The study is based mainly on primary...
Copper(II) acetate
, Article Synlett ; Volume 23, Issue 13 , 2012 , Pages 1995-1996 ; 09365214 (ISSN) ; Sharif University of Technology
2012
Abstract
(A) Chakraborty and co-workers have developed a green method for the bulk ring-opening polymerization of lactides in the presence of Cu(OAc)2 as a good catalyst to synthesize polymers with different end-terminal groups.3 These polymerizations are highly controlled leading to the formation of polymers with the expected number of average molecular weights and narrow molecular weight distribution. (B) Garden and co-workers have found that the oxidative addition of anilines with 1,4-naphthoquinone to give N-aryl-2-amino-1,4-naphthoquinones can be performed in the presence of catalytic amounts of copper(II) acetate.4 All the reactions are generally more efficient in that they are cleaner, higher...
Solving rank one revised linear systems by the scaled ABS method
, Article ANZIAM Journal ; Volume 46, Issue 2 , 2004 , Pages 225-236 ; 14461811 (ISSN) ; Sharif University of Technology
2004
Abstract
In mathematical programming, an important tool is the use of active set strategies to update the current solution of a linear system after a rank one change in the constraint matrix. We show how to update the general solution of a linear system obtained by use of the scaled ABS method when the matrix coefficient is subjected to a rank one change. © Australian Mathematical Society 2004
Rcci Curvature for Metric-Measure Space via Optimal Transport
, M.Sc. Thesis Sharif University of Technology ; Bahraini, Alireza (Supervisor) ; Ranjbar Motlagh, Alireza (Co-Advisor)
Abstract
One of the important questions in mathematics is generalized. In case of metric spaces, one of the questions is: Can we extend notions of Riemannian geometry to arbitrary metric spaces smoothly? Ricci curvature is one of the most important concepts in differential geometry. Ricci curvature is defined for the Riemannian manifold and has many applications in mathematics and physics like Einstein’s equation in relativity theory. There is a good notion for a metric space having “sectional curvature bounded below by K” or “sectional curvature bounded above by K”, due to Alexandrov. Can we define the concept of Ricci curvature in metric space? A motivation for this question comes from Gromov’s...
, M.Sc. Thesis Sharif University of Technology ; Khaloo, Alireza (Supervisor)
Abstract
Seismic design codes reduce loads by using response modification factor. Because of the reserved strength in structural elements and capacity of structure to dissipate energy, structures can be designed for lower seismic loads. This factor has modified over time. In this thesis, the effect of the reduction in behavior factor on the response of two kinds of reinforced concrete systems were evaluated. Moment resisting frames and dual systems with different heights and regularity in plan, heve been design according to the behavior factor which is recommended in the 3rd edition of the Iranian codes of practice for seismic resistance design of buildings (Standard No. 2800). Drift and...
Prediction of Financial Markets Using Combination of Artificial Intelligence and Technical Analysis
, M.Sc. Thesis Sharif University of Technology ; Haji, Alireza (Supervisor)
Abstract
Generally, nowadays, machine learning methods are used in many different areas for their superiority over other methods of prediction. Although being a tough task, stock market prediction with machine learning approaches is being spread due to satisfying results published ever yday. Machine learning methods usually use varied kinds of data ,including structured data such as market data, technical indicators and some fundamental data as well as unstructured one entailing text and graph data in order to enhance their predictability capacity. In this thesis we aimed to find out more about the importance and the contribution of structured data in prediction and we tried to attain a framework...
Dextran-graft-poly(hydroxyethyl methacrylate) gels: A new biosorbent for fluoride removal of water
, Article Designed Monomers and Polymers ; Volume 16, Issue 2 , 2013 , Pages 127-136 ; 1385772X (ISSN) ; Mousavi, S. A ; Amini Fazl, A ; Amini Fazl, M. S ; Ahmari, R ; Sharif University of Technology
2013
Abstract
Synthesis of dextran-graft-poly(hydroxyethyl methacrylate) gels as a new fluoride biosorbent was considered in this work. For this propose, the Taguchi experimental design method was used for optimizing the synthetic conditions of the gels to reach high level of fluoride absorbency. The effects of three main parameters including concentrations of monomer (hydroxyethyl methacrylate), crosslinking agent (ethylene glycol dimethacrylate), and initiator (ammonium persulfate) on the final properties of the prepared gels were investigated. The proposed mechanism for grafting and chemically crosslinking reactions was proved with equilibrium water absorption, Fourier-transformed infrared, scanning...
Optimization of synthetic conditions of a novel collagen-based superabsorbent hydrogel by Taguchi method and investigation of its metal ions adsorption
, Article Journal of Applied Polymer Science ; Volume 102, Issue 5 , 2006 , Pages 4878-4885 ; 00218995 (ISSN) ; Salimi, H ; Amini Fazl, M. S ; Kurdtabar, M ; Amini Fazl, A. R ; Sharif University of Technology
2006
Abstract
A novel biopolymer-based superabsorbent hydrogel was synthesized through chemical crosslinking by graft copolymerization of partially neutralized acrylic acid onto the hydrolyzed collagen, in the presence of a crosslinking agent and a free radical initiator. The Taguchi method, a robust experimental design, was employed for the optimization of the synthesis reaction based on the swelling capacity of the hydrogels. This method was applied for the experiments and standard L16 orthogonal array with three factors and four levels were chosen. The critical parameters that have been selected for this study are crosslinker (N,N′-methylene bisacrylamide), initiator (potassium persulfate), and monomer...
Sparsity and infinite divisibility
, Article IEEE Transactions on Information Theory ; Volume 60, Issue 4 , 2014 , Pages 2346-2358 ; ISSN: 00189448 ; Unser, M ; Sharif University of Technology
2014
Abstract
We adopt an innovation-driven framework and investigate the sparse/compressible distributions obtained by linearly measuring or expanding continuous-domain stochastic models. Starting from the first principles, we show that all such distributions are necessarily infinitely divisible. This property is satisfied by many distributions used in statistical learning, such as Gaussian, Laplace, and a wide range of fat-tailed distributions, such as student's-t and α-stable laws. However, it excludes some popular distributions used in compressed sensing, such as the Bernoulli-Gaussian distribution and distributions, that decay like exp (-O(|x|p)) for 1 < p < 2. We further explore the implications of...
Deterministic construction of binary, bipolar, and ternary compressed sensing matrices
, Article IEEE Transactions on Information Theory ; Volume 57, Issue 4 , April , 2011 , Pages 2360-2370 ; 00189448 (ISSN) ; Marvasti, F ; Sharif University of Technology
2011
Abstract
In this paper, we establish the connection between the Orthogonal Optical Codes (OOC) and binary compressed sensing matrices. We also introduce deterministic bipolar m × n RIP fulfilling ± 1 matrices of order k such that m ≤ script O sign (k(log2 n) log2 k/ln log2 k). The columns of these matrices are binary BCH code vectors where the zeros are replaced by -1. Since the RIP is established by means of coherence, the simple greedy algorithms such as Matching Pursuit are able to recover the sparse solution from the noiseless samples. Due to the cyclic property of the BCH codes, we show that the FFT algorithm can be employed in the reconstruction methods to considerably reduce the computational...
Multi-level authorisation model and framework for distributed semantic-aware environments
, Article IET Information Security ; Volume 4, Issue 4 , 2010 , Pages 301-321 ; 17518709 (ISSN) ; Jalili, R ; Sharif University of Technology
2010
Abstract
Semantic technology is widely used in distributed computational environments to increase interoperability and machine readability of information through giving semantics to the underlying information and resources. Semantic-awareness, distribution and interoperability of new generation of distributed systems demand an authorisation model and framework that satisfies essential authorisation requirements of such environments. In this study, the authors propose an authorisation model and framework based on multi-security-domain architecture for distributed semantic-aware environments. The proposed framework is founded based on the MA(DL)2 logic, which enables policy specification and inference...
A new framework to train autoencoders through non-smooth regularization
, Article IEEE Transactions on Signal Processing ; Volume 67, Issue 7 , 2019 , Pages 1860-1874 ; 1053587X (ISSN) ; Ghaemmaghami, S ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Deep structures consisting of many layers of nonlinearities have a high potential of expressing complex relations if properly initialized. Autoencoders play a complementary role in training a deep structure by initializing each layer in a greedy unsupervised manner. Due to the high capacity presented by autoencoders, these structures need to be regularized. While mathematical regularizers (based on weight decay, sparsity, etc.) and structural ones (by way of, e.g., denoising and dropout) have been well studied in the literature, quite a few papers have addressed the problem of training autoencoder with non-smooth regularization. In this paper, we address the problem of training autoencoder...
Lowering mutual coherence between receptive fields in convolutional neural networks
, Article Electronics Letters ; Volume 55, Issue 6 , 2019 , Pages 325-327 ; 00135194 (ISSN) ; Ghaemmaghami, S ; Sharif University of Technology
Institution of Engineering and Technology
2019
Abstract
It has been shown that more accurate signal recovery can be achieved with low-coherence dictionaries in sparse signal processing. In this Letter, the authors extend the low-coherence attribute to receptive fields in convolutional neural networks. A new constrained formulation to train low-coherence convolutional neural network is presented and an efficient algorithm is proposed to train the network. The resulting formulation produces a direct link between the receptive fields of a layer through training procedure that can be used to extract more informative representations from the subsequent layers. Simulation results over three benchmark datasets confirm superiority of the proposed...
Towards improving robustness of deep neural networks to adversarial perturbations
, Article IEEE Transactions on Multimedia ; Volume 22, Issue 7 , 2020 , Pages 1889-1903 ; Ghaemmaghami, S ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
Deep neural networks have presented superlative performance in many machine learning based perception and recognition tasks, where they have even outperformed human precision in some applications. However, it has been found that human perception system is much more robust to adversarial perturbation, as compared to these artificial networks. It has been shown that a deep architecture with a lower Lipschitz constant can generalize better and tolerate higher level of adversarial perturbation. Smooth regularization has been proposed to control the Lipschitz constant of a deep architecture and in this work, we show how a deep convolutional neural network (CNN), based on non-smooth regularization...
Calculus for composite authorities' policy derivation in shared domains of pervasive computing environments
, Article 11th International Conference on Computer and Information Technology, ICCIT 2008, Khulna, 25 December 2008 through 27 December 2008 ; March , 2008 , Pages 21-28 ; 9781424421367 (ISBN) ; Jalili, R ; Sharif University of Technology
2008
Abstract
The decentralized security management in a pervasive computing environment' requires apportioning the environment into several security domains. In each security domain' an administrator (we call it authority) is responsible for specifying the security policies of the domain. Overlapping of security domains results in the requirement of cooperative security management in the shared/ overlapping domains. To satisfy this requirement' we propose an abstract security model' as well as its supplementary calculus of composite authorities. The security model is based on deontic logic and is independent of the domains' heterogeneity. The model's policy language (we call it MASL) enables multiple...
Convergence analysis of an iterative method for the reconstruction of multi-band signals from their uniform and periodic nonuniform samples
, Article Sampling Theory in Signal and Image Processing ; Volume 7, Issue 2 , 1 May , 2008 , Pages 113-129 ; 15306429 (ISSN) ; Marvasti, F ; Sharif University of Technology
2008
Abstract
One of the proposed methods for recovery of a band-limited signal from its samples, whether uniform or nonuniform, is the so-called Frame Method. In this method the original signal is reconstructed by iterative use of sampling-filtering blocks. Convergence of this method for linear invertible operators has been previously proved. In this paper we show that this method for non-invertible periodic nonuniform samplings as well as non-invertible uniform samples of bandpass (or multi-band) signals will lead to the pseudo-inverse solution. Convergence conditions in case of additive noise will also be discussed. © 2008 Sampling Publishing
Towards robust visual transformer networks via k-sparse attention
, 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 4053-4057 ; 15206149 (ISSN); 9781665405409 (ISBN) ; Ghaemmaghami, S ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
Transformer networks, originally developed in the community of machine translation to eliminate sequential nature of recurrent neural networks, have shown impressive results in other natural language processing and machine vision tasks. Self-attention is the core module behind visual transformers which globally mixes the image information. This module drastically reduces the intrinsic inductive bias imposed by CNNs, such as locality, while encountering insufficient robustness against some adversarial attacks. In this paper we introduce K-sparse attention to preserve low inductive bias, while robustifying transformers against adversarial attacks. We show that standard transformers attend...
Deterministic Compressed Sensing
, Ph.D. Dissertation Sharif University of Technology ; Marvasti, Farrokh (Supervisor)
Abstract
The emerging field of compressed sensing deals with the techniques of combining the two blocks of sampling and compression into a single unit without compromising the performance. Clearly, this is not feasible for any general signal; however, if we restrict the signal to be sparse, it becomes possible. There are two main challenges in compressed sensing, namely the sampling process and the reconstruction methods. In this thesis, we will focus only on the deterministic sampling process as opposed to the random sampling. The sampling methods discussed in the literature are mainly linear, i.e., a matrix is used as the sampling operator. Here, we first consider linear sampling methods and...
Interpretation of the Seven Errors in Bulk Material Sampling with the Aim of Providing a Guideline (Protocol) for Sampling From Liquids - Case of Edible Oil
, M.Sc. Thesis Sharif University of Technology ; Mahlooji, Hashem (Supervisor)
Abstract
Sampling is so deep-rooted in our habits that it usually takes place unconsciously. A large number of books and articles have been published in this field. The connection between sampling and quality control is the reason that many industries have focused their attention on sampling; however, only a few numbersare familiar with bulk material sampling related issues. Describing this theory along with its seven errors is the main object of this research. Using this theory, characteristics of the lot of interest was analyzed. Creating necessary conditions for assuring sampling correctness is very critical and if these conditions cannot be provided, implementing some part of the theory issues...