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		A new pipeline implementation of an adaptive IIR filter for noise reduction application
, Article IEEE International Symposium on Communications and Information Technologies: Smart Info-Media Systems, ISCIT 2004, Sapporo, 26 October 2004 through 29 October 2004 ; Volume 1 , 2004 , Pages 577-581 ; 0780385934 (ISBN) ; Manzuri, M. T ; Ayat, S ; Sharif University of Technology
								
								
					2004
				
							
				
		
							Abstract
				
					
			
		
										
				the parallel form in adaptive HR filtering is an efficient realization that provides robust stability monitoring with less complexity than that of the direct form. This paper presents an implementation of two line parallel structure employing a real orthogonal transform and real coefficients second-order section as sub filters on FPGA. Architecture that is implemented is in pipeline fashion and it is independent from its building blocks and they may have its own implementation or in other system numbering. In the last section, we compared throughput of our architecture with a Ti DSP (TMS320C3x/4x), the results show that this architecture works better than the DSP  
				
				
				
					ECG denoising using modulus maxima of wavelet transform
, Article Proceedings of the 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society: Engineering the Future of Biomedicine, EMBC 2009 ; 2009 , Pages 416-419 ; 1557170X (ISSN) ; Shamsollahi, M. B ; Mozaffari, B ; Kharabian, S ; Sharif University of Technology
								
								
					2009
				
							
				
		
							Abstract
				
					
			
		
										
				ECG denoising has always been an important issue in medical engineering. The purposes of denoising are reducing noise level and improving signal to noise ratio (SNR) without distorting the signal. This paper proposes a method for removing white Gaussian noise from ECG signals. The concepts of singularity and local maxima of the wavelet transform modulus were used for analyzing singularity and reconstructing the ECG signal. Adaptive thresholding was used to remove white Gaussian noise modulus maximum of wavelet transform and then reconstruct the signal  
				
				
				
					ECG denoising using modulus maxima of wavelet transform
, Article Proceedings of the 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society: Engineering the Future of Biomedicine, EMBC 2009, 2 September 2009 through 6 September 2009, Minneapolis, MN ; 2009 , Pages 416-419 ; 9781424432967 (ISBN) ; Shamsollahi, M. B ; Mozaffari, B ; Kharabian, S ; Sharif University of Technology
								
								
					2009
				
							
				
		
							Abstract
				
					
			
		
										
				ECG denoising has always been an important issue in medical engineering. The purposes of denoising are reducing noise level and improving signal to noise ratio (SNR) without distorting the signal. This paper proposes a method for removing white Gaussian noise from ECG signals. The concepts of singularity and local maxima of the wavelet transform modulus were used for analyzing singularity and reconstructing the ECG signal. Adaptive thresholding was used to remove white Gaussian noise modulus maximum of wavelet transform and then reconstruct the signal. ©2009 IEEE  
				
				
				
					Wavelet based speech enhancement using a new thresholding algorithm
, Article 2004 International Symposium on Intelligent Multimedia, Video and Speech Processing, ISIMP 2004, Hong Kong, China, 20 October 2004 through 22 October 2004 ; 2004 , Pages 238-241 ; 0780386884 (ISBN) ; Manzuri, M. T ; Dianat, R ; Sharif University of Technology
								
								
					2004
				
							
				
		
							Abstract
				
					
			
		
										
				The Wavelet based speech enhancement is considered. In this method, the noisy signal transfers to wavelet domain. Then with applying a thresholding algorithm, the wavelet coefficients will be improved. At last using the inverse wavelet transform the enhanced signal will be obtained. In this paper, we have presented a new method for thresholding algorithm. We compared our algorithm with some of the most popular methods by several experimental tests. Both subjective and objective tests show better performance and achievements  
				
				
				
					A Compact Spectral Model for Convolutional Neural Network
, Article Lecture Notes in Networks and Systems ; Volume 559 LNNS , 2023 , Pages 100-120 ; 23673370 (ISSN); 978-303118460-4 (ISBN) ; Rizvi, S.M ; Abdellatef, H ; Ab Rahman, A. A. H ; Manan, S. S. A ; Arai K ; Sharif University of Technology
								
					Springer Science and Business Media Deutschland GmbH 
				
								
								
					2023
				
							
				
		
							Abstract
				
					
			
		
										
				The convolutional neural network (CNN) has gained widespread adoption in computer vision (CV) applications in recent years. However, the high computational complexity of spatial (conventional) CNNs makes real-time deployment in CV applications difficult. Spectral representation (frequency domain) is one of the most effective ways to reduce the large computational workload in CNN models, and thus beneficial for any processing platform. By reducing the size of feature maps, a compact spectral CNN model is proposed and developed in this paper by utilizing just the lower frequency components of the feature maps. When compared to similar models in the spatial domain, the proposed compact spectral... 
				
				
				
					An improved wavelet-based speech enhancement by using speech signal features
, Article Computers and Electrical Engineering ; Volume 32, Issue 6 , 2006 , Pages 411-425 ; 00457906 (ISSN) ; Manzuri Shalmani, M. T ; Dianat, R ; Sharif University of Technology
								
								
					2006
				
							
				
		
							Abstract
				
					
			
		
										
				This paper presents a new speech enhancement system that works in wavelet domain. The core of system is an improved WaveShrink module. First, different parameters of WaveShrink are studied; then, based on the features of speech signal, an improved wavelet-based speech enhancement system is proposed. The system uses a novel thresholding algorithm, and introduces a new method for threshold selection. Moreover, the efficiency of system has been increased by selecting more suitable parameters for voiced, unvoiced and silence regions, separately. The proposed system has been evaluated on different sentences under various noise conditions. The results show a plausible improvement in performance of... 
				
				
				
					An improved spectral subtraction speech enhancement system by using an adaptive spectral estimator
, Article Canadian Conference on Electrical and Computer Engineering 2005, Saskatoon, SK, 1 May 2005 through 4 May 2005 ; Volume 2005 , 2005 , Pages 261-264 ; 08407789 (ISSN) ; Manzuri, M. T ; Dianat, R ; Kabudian, J ; Sharif University of Technology
								
								
					2005
				
							
				
		
							Abstract
				
					
			
		
										
				Spectral subtraction is one of the most famous and common-used methods for speech enhancement. The main weakness of this method is the production of an annoying noise called musical noise. In this paper, we have reduced the musical noise and improved the quality of enhanced speech by increasing the accuracy of the system spectral estimator. This method is useful for speech enhancement systems in which the speech signal is degraded by stationary or near-stationary noises. Different experimental results in different SNRs confirmed the better performance of our system from both objective and subjective views, which means better quality and more SNR improvement. © 2005 IEEE  
				
				
				
					The relationship between an EFL teacher's gender and students' willingness to communicate
, Article International Journal of Communication and Linguistic Studies ; Volume 10, Issue 4 , 2013 , Pages 17-29 ; 23277882 (ISSN) ; Pakzadian, S. S
								
					Common Ground Publishing 
				
								
								
					2013
				
							
				
		
							Abstract
				
					
			
		
										
				Learning a foreign language encompasses a process of trial and error that can lead to the progression of the learner's interlanguage, meaning that the learners make use of their language knowledge that receives feedback and brings about progress through diagnosis of the problems and being corrected by the teacher. Therefore, there exists a need to analyze the underlying reasons causing the students to remain taciturn with a low willingness to communicate (WTC) during a language class. There has been much work done investigating the role of the learner's stable personal characteristics (traits) along with their situational changes at a specific time (states) that influence the student's... 
				
				
				
					An automated simple algorithm for realistic pore network extraction from micro-tomography images
, Article Journal of Petroleum Science and Engineering ; Vol. 123, issue , 2014 , pp. 164-171 ; ISSN: 09204105 ; Jamshidi, S ; Salehi, S
								
								
					2014
				
							
				
		
							Abstract
				
					
			
		
										
				Using 3-D scanned data to analyze and extract pore network plays a vital role in investigation of porous media's characteristics. In this paper, a new simple method is developed to detect pores and throats for analyzing the connectivity and permeability of the network. This automated method utilizes some of the common and well-known image processing functions which are widely accessible by researchers and this has led to an easy algorithm implementation. In this method, after polishing and quality control of images, using city-block distance function and watershed segmentation algorithm, pores and throats are detected and 3-D network is produced. This method can also be applied on 2-D images... 
				
				
				
					Discrimination of heart arrhythmias using novel features in heart rate phase space
, Article Computing in Cardiology ; Volume 40 , Sept , 2013 , Pages 1035-1038 ; 23258861 (ISSN); 9781479908844 (ISBN) ; Rezaei, S ; Salavatian, S
								
								
					2013
				
							
				
		
							Abstract
				
					
					
			
				
	
In this paper, we try to recognize and distinguish different groups of arrhythmia using novel features which have been obtained from the heart rate's phase space in recent years. For this purpose, we used Triangular Phase Space Mapping (TPSM) and Parabolic Phase Space Mapping (PPSM). For recognition, we used three groups of 15 subjects using the Physionet database (Arrhythmia, Congestive Heart Failure (CHF), and Atrial Fibrillation (AF)) with Normal Sinus Rhythm (NSR). The obtained features discriminate arrhythmia from NSR by p
				
				
				
					 
			
		
										
				An intelligent hybrid classification algorithm integrating fuzzy rule-based extraction and harmony search optimization: Medical diagnosis applications
, Article Knowledge-Based Systems ; Volume 220 , 2021 ; 09507051 (ISSN) ; Abdullah, S ; Akhavan Niaki, S. T ; Banihashemi, S ; Sharif University of Technology
								
					Elsevier B.V 
				
								
								
					2021
				
							
				
		
							Abstract
				
					
			
		
										
				Uncertainty is a critical factor in medical datasets needed to be overcome for increasing diagnosis efficiency. This paper proposes an intelligent classification algorithm comprising a fuzzy rule-based approach, a harmony search (HS) algorithm, and a heuristic algorithm to classify medical datasets intelligently. Two fuzzy approaches, as well as orthogonal and triangular fuzzy sets, are first utilized to define the attributes of data. Then, an HS algorithm is integrated with a heuristic to generate fuzzy rules to select the best rules in the fuzzy rule-based systems. Moreover, to improve the performance of the proposed classification approach, a three-phase parameter tuning approach is... 
				
				
				
					Performance evaluation of shared hosting security methods
, Article Proc. of the 11th IEEE Int. Conference on Trust, Security and Privacy in Computing and Communications, TrustCom-2012 - 11th IEEE Int. Conference on Ubiquitous Computing and Communications ; 2012 , Pages 1310-1315 ; 9780769547459 (ISBN) ; Arshad, S ; Khoshkdahan, S ; Sharif University of Technology
								
								
					2012
				
							
				
		
							Abstract
				
					
			
		
										
				Shared hosting is a kind of web hosting in which multiple websites reside on one webserver. It is cost-effective and makes the administration easier for websites' owners. However, shared hosting has some performance and security issues. In default shared hosting configuration, all websites' scripts are executed under the webserver's user account regardless of their owners. Therefore, a website is able to access other websites' resources. This security problem arises from lack of proper isolation between different websites hosted on the same webserver. In this survey, we have examined different methods for handling mentioned security issue. Also we evaluated the performance of mentioned... 
				
				
				
					The behaviour of an artificially cemented sandy gravel
, Article Geotechnical and Geological Engineering ; Volume 23, Issue 5 , 2005 , Pages 537-560 ; 09603182 (ISSN) ; Hosseini, S. M ; Toll, D. G ; Yasrebi, S. S ; Sharif University of Technology
								
								
					2005
				
							
				
		
							Abstract
				
					
			
		
										
				The major section of the city of Tehran, Iran has been developed on cemented coarse-grained alluvium. This deposit consists of gravely sand to sandy gravel with some cobbles and is dominantly cemented by carbonaceous materials. In order to understand the mechanical behaviour of this soil, a series of undrained triaxial compression tests and unconfined compression tests were performed on uncemented and artificially cemented samples. Portland cement type I was used as the cementation agent for preparing artificially cemented samples. Uncemented samples and lightly cemented samples (1.5% cement) tested at high confining pressure showed contractive behaviour accompanied with positive excess pore... 
				
				
				
					An imperialist competitive algorithm approach for multi-objective optimization of direct coupling photovoltaic-electrolyzer systems
, Article International Journal of Hydrogen Energy ; Vol. 39, Issue 33 , 11 November , 2014 , pp. 18743-18757 ; ISSN: 03603199 ; Sayedin, F ; Khavas, S. S
								
								
					2014
				
							
				
		
							Abstract
				
					
			
		
										
				In the context of sustainable clean hydrogen production pathways, photovoltaic-electrolyzer systems are one of the most promising alternatives for acquiring hydrogen from renewable energy sources. In fact, determining the optimal set of design and operating variables are always a key issue while coupling directly renewable electricity sources to PEM electrolyzers. Few previous studies have attempted to find the optimal size and operational condition of directly coupled photovoltaic-electrolyzer (PV/El) systems in order to maximize the hydrogen production or to minimize energy transfer loss between photovoltaic devices and the electrolyzer. Nevertheless an easy and efficient approach still... 
				
				
				
					Kalman filter based packet loss replacement in presence of additive noise
, Article 2012 25th IEEE Canadian Conference on Electrical and Computer Engineering: Vision for a Greener Future, CCECE 2012 ; 2012 ; 9781467314336 (ISBN) ; Ghorshi, S ; Tahaei, A
								
								
					2012
				
							
				
		
							Abstract
				
					
			
		
										
				A major problem in real-time packet-based communication systems, is misrouted or delayed packets which results in degraded perceived voice quality. If packets are not available on time, the packets are considered as lost. The easiest solution in a network terminal receiver is to replace silence for the duration of lost speech segments. In a high quality communication system, to avoid degradation in speech quality due to packet loss, a suitable method or algorithm is needed to replace the missing segments of speech. In this paper, we introduce an adaptive filter for replacement of lost speech segment. In this method Kalman filter as a state-space based method will be used to predict the... 
				
				
				
					Investigation of Mesh Sensitivity Influence to Determine Crack Characteristic by Finite Element Methods
, Article Journal of Failure Analysis and Prevention ; Volume 16, Issue 3 , 2016 , Pages 506-512 ; 15477029 (ISSN) ; Mirjavadi, S. S ; Asli, S. A ; Sharif University of Technology
								
					Springer New York LLC 
				
								
								
					2016
				
							
				
		
							Abstract
				
					
			
		
										
				In this research, an extended finite element model has been investigated. Investigation of opening and closure stress always has been one of the difficult parameters to analysis of results; therefore, the utilization of finite element methods would be a good and logical alternative for this purpose. In addition, linear elastic fracture criteria are used for validation of numerical results from the simulation. In this work, a detailed analysis of the influence of different parameters in the results of a specific specimen with a semi-elliptical tooling groove in terms of closure and opening stress is presented, and the impact of optimum element size in fracture characteristic in various load... 
				
				
				
					Investigation of the effect of nanosilica on rheological, thermal, mechanical, structural, and piezoelectric properties of poly(vinylidene fluoride) nanofibers fabricated using an electrospinning technique
, Article Industrial and Engineering Chemistry Research ; Volume 56, Issue 44 , 2017 , Pages 12596-12607 ; 08885885 (ISSN) ; Ahmad Ramazani, S. A ; Talebi, S ; Fattahpour, S ; Hasany, M ; Sharif University of Technology
								
								
					2017
				
							
				
		
							Abstract
				
					
			
		
										
				The effects of different nano-SiO2 contents on the rheological properties of poly(vinylidene fluoride) (PVDF) solution and mechanical, thermal, structural, and piezoelectric properties of composite nanofibers were investigated. Results showed an increase in fiber diameter (∼125 to 350 nm) and ∼450% increase in tensile strength as the content of nano-SiO2 particles increased. The degree of crystallinity decreased by 19% as the nano-SiO2 content increased by 2% (w/w). Further investigation demonstrated that silica could significantly improve the piezoelectric properties of PVDF nanofibers as the output voltage showed an increase in the presence of silica attributed to change in the crystalline... 
				
				
				
					A method for real-time safe navigation in noisy environments
, Article 2013 18th International Conference on Methods and Models in Automation and Robotics, MMAR 2013, Miedzyzdroje ; 2013 , Pages 329-333 ; 9781467355063 (ISBN) ; Kamali, E ; Niknezhad, M. R ; Monfared, S. S. M. S ; Sharif University of Technology
								
								
					2013
				
							
				
		
							Abstract
				
					
			
		
										
				The challenge of finding an optimized and reliable path dates back to emersion of mobile robots. Several approaches have been developed that have partially answered this need. Satisfying results in previous implementations has led to an increased utilization of sampling-based motion planning algorithms in recent years, especially in high degrees of freedom (DOF), fast evolving environments. Another advantage of these algorithms is their probabilistic completeness that guarantees delivery of a path in sufficient time, if one exists. On the other hand, sampling based motion planners leave no comment on safety of the planned path. This paper suggests biasing the Rapidly-exploring Random Trees... 
				
				
				
					A generalization of the swartz equality
, Article Glasgow Mathematical Journal ; Vol. 56, issue. 2 , May , 2014 , pp. 381-386 ; ISSN: 00170895 ; Fakhari, S. A. S ; Yassemi, S ; Sharif University of Technology
								
								
					2014
				
							
				
		
							Abstract
				
					
			
		
										
				For a given (d-1)-dimensional simplicial complex Γ, we denote its h-vector by h(Γ)=(h 0(Γ),h 1(Γ),...,hd (Γ)) and set h -1(Γ)=0. The known Swartz equality implies that if Δ is a (d-1)-dimensional Buchsbaum simplicial complex over a field, then for every 0 ≤ i ≤ d, the inequality ihi (Δ)+(d-i+1)h i-1(Δ) ≥ 0 holds true. In this paper, by using these inequalities, we give a simple proof for a result of Terai (N. Terai, On h-vectors of Buchsbaum Stanley-Reisner rings, Hokkaido Math. J. 25(1) (1996), 137-148) on the h-vectors of Buchsbaum simplicial complexes. We then generalize the Swartz equality (E. Swartz, Lower bounds for h-vectors of k-CM, independence, and broken circuit complexes, SIAM J.... 
				
				
				
					Hardware-in-the-loop optimization of an active vibration controller in a flexible beam structure using evolutionary algorithms
, Article Journal of Intelligent Material Systems and Structures ; Vol. 25, issue. 10 , 2014 , p. 1211-1223 ; Hosseini Kordkheili, S. A ; Afshari, S. S ; Sharif University of Technology
								
								
					2014
				
							
				
		
							Abstract
				
					
			
		
										
				In this study, active vibration control of a cantilevered flexible beam structure equipped with bonded piezoelectric sensor/actuators is investigated. The linear quadratic regulator technique together with an observer is adopted to design the controller as well as to provide the full-state feedback. Two different approaches are subsequently used for simultaneously integrated optimization of the controller and observer parameters. In the first approach, a linear experimental model of the system is obtained using identification techniques, and the optimization is then performed based on a computer simulation of the system. However, in the second approach, a hardware-in-the-loop optimization... 
				
				
				
					