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    Coevolution of input sensors and recognition system to design a very low computation isolated, word speech recognition system

    , Article Scientia Iranica ; Volume 14, Issue 6 , 2007 , Pages 625-630 ; 10263098 (ISSN) Halavati, R ; Shouraki, S. B ; Sharif University of Technology
    Sharif University of Technology  2007
    Appropriate sensors are a crucial necessity for the success of recognition systems. Nature has always coevolved sensors and recognition systems and this can also be done in artificially intelligent systems. To get a very fast isolated word speech recognition system for a small embedded speech recognizer, an evolutionary approach has been used to create together the required sensors and appropriate recognition structures. The input sensors are designed and evolved through inspiration by the human auditory system and the classification is done by artificial neural networks. The resulting system is compared with a widely used speech recognition system, and the results are quite satisfactory. ©... 

    Designing an Intelligent Heart Disease Prediction System Via Data Mining Techniques

    , M.Sc. Thesis Sharif University of Technology Sharabiani, Ashkan (Author) ; Shavandi, Hassan (Supervisor)
    The healthcare industry collects huge amounts of healthcare data which, unfortunately, are not“mined” to discover hidden information for effective decision making. Discovery of hidden patterns and relationships often goes nexploited. Advanced data mining techniques can help remedy this situation. The diagnosis of diseases is a vital and intricate job in medicine. The recognition of heart disease from diverse features or signs is a multi-layered problem that is not free from false assumptions and is frequently accompanied by impulsive effects. Thus the attempt to exploit knowledge and experience of several specialists and clinical screening data of patients composed in databases to assist the... 

    Steganography in TeX documents

    , Article Proceedings of 2008 3rd International Conference on Intelligent System and Knowledge Engineering, ISKE 2008, Xiamen, 17 November 2008 through 19 November 2008 ; December , 2008 , Pages 1363-1366 ; 9781424421978 (ISBN) Shirali Shahreza, M ; Shirali Shahreza, S ; Sharif University of Technology
    Steganography is a method for hidden exchange of information by hiding data in a cover media such as image or sound. Text Steganography is one of the most difficult methods because a text file is not a proper media to hide data in it. In this paper we propose a new text Steganography method. In this method, we hide data in TeX documents. This method hides the data in places where there is a ligature such as "fi". © 2008 IEEE  

    Integration of symmetry and macro-operators in planning

    , Article 6th Mexican International Conference on Artificial Intelligence, MICAI 2007, Aguascalientes, 4 November 2007 through 10 November 2007 ; Volume 4827 LNAI , 2007 , Pages 1056-1066 ; 03029743 (ISSN); 9783540766308 (ISBN) Houshmandan, A ; Ghassem Sani, G ; Nakhost, H ; Sharif University of Technology
    Springer Verlag  2007
    Macro-operators are sequences of actions that can guide a planner to achieve its goals faster by avoiding search for those sequences. However, using macro-operators will also increase the branching factor of choosing operators, and as a result making planning more complex and less efficient. On the other hand, the detection and exploitation of symmetric structures in planning problems can reduce the search space by directing the search process. In this paper, we present a new method for detecting symmetric objects through subgraph-isomorphism, and exploiting the extracted information in macrooperator selection. The method has been incorporated into HSP2, and tested on a collection of... 

    An agent-based architecture with centralized management for a distance learning system

    , Article International Conference on Computational Intelligence and Multimedia Applications, ICCIMA 2007, Sivakasi, Tamil Nadu, 13 December 2007 through 15 December 2007 ; Volume 1 , 2008 , Pages 68-76 ; 0769530508 (ISBN); 9780769530505 (ISBN) Nargesian, F ; Nazemi, E ; Sharif University of Technology
    In this paper we have proposed a multi-agent architecture for an Intelligent Tutoring System using TROPOS methodology. Basic assumptions of constructivist learning have been taken into account in analysis and design activities. Nine types of agents are distinguished in the presented system. We have centralized management in the proposed architecture which is done by an agent called Manager Agent. This strategy of centralized management will result in a more coherent and effective Tutoring System than other systems not using such an agent, since it applies control flow of agents and decreases agents ' useless communications which may cause destructive congestion in system. This text discusses... 

    Intelligent operation using terrain following flight in unmanned aerial vehicles

    , Article 2007 IEEE Aerospace Conference, Big Sky, MT, 3 March 2007 through 10 March 2007 ; 2007 ; 1095323X (ISSN) ; 1424405254 (ISBN); 9781424405251 (ISBN) Rahim, M ; Malaek, S. M. B ; Sharif University of Technology
    A novel approach in Terrain Following/Terrain Avoidance (TF/TA) flight is proposed. Due to existing unknown terrain during flight, an intelligent approach is used. Intelligence is implemented using the fuzzy approach. This method can be used in off-line design in trajectory planning which has wide applications in TF/TA maneuvers in unmanned aerial vehicles. A relationship between slope of terrain and aircraft height with speed of aircraft is constructed by fuzzy approach. This work is performed for a two dimensional Terrain Following Flight. This method is state of the art in literature. © 2007 IEEE  

    Hydrodynamics Modeling and Self Orginizing Control of Marine Vehicles

    , M.Sc. Thesis Sharif University of Technology Taghi, Amir Hossein (Author) ; Sayyadi, Hassan (Supervisor)
    Dynamic positioning system is a controller system used to maintain the position and heading of a vessel with no use of anchors, jack ups but only using the propellers installed on the vessel. A vessel has six degrees of freedom, including three rotations and three transfer. In dynamic positioning systems, the vessel is controlled only on the horizontal plane such that its position and heading are controlled according to predetermined values. To achieve this, position and heading of the vessel is determined and the controller system computes the direction and required power of each propeller. Preliminary systems utilized PID controllers. As the control science has advanced, model based... 

    Design and Implementation of an Intelligent Analyzer for Hand Rehabilitation

    , Ph.D. Dissertation Sharif University of Technology Mobini, Amir (Author) ; Saadat Foumani, Mahmoud (Supervisor) ; Behzadipour, Saeed (Supervisor)
    In recent years there have been a growing number of patients who are no more capable of leading an independent life, due to strokes, accident, or a variety of diseases. Thus, vast fields of physical rehabilitation have come into the attention of goverments and researchers. High costs of rehabilitation programs and their length on one hand, and the difficulties of commuting such patients to rehabilitation centers on the other hand, has made health department of various countries to look for alternative solutions.In this thesis, a computerized system has been designed and implemented in order to assess and guide patients in their rehabilitation excercises without needing any direct contact.... 

    A low power 1.2 GS/s 4-bit flash ADC in 0.18 μm CMOS

    , Article Proceedings of IEEE East-West Design and Test Symposium, EWDTS 2013 ; 2013 ; 9781479920969 (ISBN) Chahardori, M ; Sharifkhani, M ; Sadughi, S ; Sharif University of Technology
    A low power 4-bit flash ADC is proposed. A new power reduction technique is employed which deactivates the unused blocks in the converter structure in order to reduce the power consumption. A new method for built-in threshold voltage generation together with a new offset calibration method is used to further reduce the power consumption in the converter. Monte-Carlo simulation shows that after calibration both the INL and the DNL are lower than 0.35 LSB. The converter achieves 3.5 effective number of bits (ENOB) at 1.2 GS/s sampling rate after the offset calibration is performed. It consumes 10 mW from a 1.8 V supply, yielding a FoM of 560 fJ/conversion.step in a 0.18 μm standard CMOS... 

    New SNDR enhancement techniques in pipelined ADC

    , Article 2013 21st Iranian Conference on Electrical Engineering ; May , 2013 , Page(s): 1 - 5 ; 9781467356343 (ISBN) Ghadi, M. H ; Safavi, S. M ; Sharifkhani, M ; Sharif University of Technology
    Signal to Noise and Distortion Ratio (SNDR) is widely chosen for dynamic characterization of ADC. For pipelined ADC in which the inner circuits' errors accumulate at the output, analysis of the origins of SNDR and its characterization can be very hard. However, due to a relationship between maximum INL of ADC and the distortion in its output codes, SNDR can be derived as a function of maximum INL value and its position in output codes. Utilizing this relationship, this paper develops two methods for SNDR enhancement that do not cost much power. The 50k sampled Monte-Carlo simulation in the behavioral level indicates 75% increase in the possibility of having SNDR > 60db just by utilizing... 

    Finite-SNR diversity-multiplexing tradeoff in multi-relay channels

    , Article 2013 Iran Workshop on Communication and Information Theory ; 2013 ; 9781467350235 (ISBN) Haddadpour, F ; Gholami, E ; Rastegar, S. H ; Behroozi, H ; Sharif University of Technology
    In this paper, we investigate the diversity-multiplexing tradeoff (DMT) for multi-relay channels in finite-SNR regime. In our analysis, we consider the decode and forward (DF) relaying strategy and a line of sight path from source to destination. First, we determine the outage probability in a multi-relay scenario and obtain its exact analytical expressions. Then, the outage probability of a multi-relay channel with relay selection is calculated and provided as a closed-form expression. Based on these results, we determine the DMT in finite-SNR regime. Finally, using simulation results, we show that our analysis has accurate results which coincides with that of obtained from Monte-Carlo... 

    Reconfiguration and capacitor placement in radial distribution systems for loss reduction and reliability enhancement

    , Article 2011 16th International Conference on Intelligent System Applications to Power Systems, ISAP 2011 ; 2011 Rezaei, P ; Vakilian, M ; Hajipour, E ; Sharif University of Technology
    This paper applies different approaches to solve network reconfiguration and capacitor placement/setting problem. First, reconfiguration and capacitor placement is solved for power loss minimization. Second, medium and long-term planning perspective is considered for the problem which takes into account reliability cost in addition to energy losses cost. A heuristic algorithm is used in this study for reliability evaluation considering protection schemes and isolation points in the distribution network. The problems are solved by Harmony Search Algorithm, and it is shown that its performance is much more satisfactory than several other metaheuristic algorithms to solve reconfiguration and... 

    New drift detection method for data streams

    , Article Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) ; Volume 6943 LNAI , 2011 , Pages 88-97 ; 03029743 (ISSN) ; 9783642238567 (ISBN) Sobhani, P ; Beigy, H ; Sharif University of Technology
    Correctly detecting the position where a concept begins to drift is important in mining data streams. In this paper, we propose a new method for detecting concept drift. The proposed method, which can detect different types of drift, is based on processing data chunk by chunk and measuring differences between two consecutive batches, as drift indicator. In order to evaluate the proposed method we measure its performance on a set of artificial datasets with different levels of severity and speed of drift. The experimental results show that the proposed method is capable to detect drifts and can approximately find concept drift locations  

    Temporal dynamics of connectivity and epidemic properties of growing networks

    , Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Volume 93, Issue 1 , 2016 ; 15393755 (ISSN) Fotouhi, B ; Khani Shirkoohi, M ; Sharif University of Technology
    American Physical Society  2016
    Traditional mathematical models of epidemic disease had for decades conventionally considered static structure for contacts. Recently, an upsurge of theoretical inquiry has strived towards rendering the models more realistic by incorporating the temporal aspects of networks of contacts, societal and online, that are of interest in the study of epidemics (and other similar diffusion processes). However, temporal dynamics have predominantly focused on link fluctuations and nodal activities, and less attention has been paid to the growth of the underlying network. Many real networks grow: Online networks are evidently in constant growth, and societal networks can grow due to migration flux and... 

    Smart materials, characteristics, applications and modeling

    , Article Proceedings of the ASME Conference on Smart Materials, Adaptive Structures and Intelligent Systems 2009, SMASIS2009, 21 September 2009 through 23 September 2009, Oxnard, CA ; Volume 1 , 2009 , Pages 649-661 ; 9780791848968 (ISBN) Amini, A ; Mehdigholi, H ; Elahinia, M ; Sharif University of Technology
    This paper reviews the research results, characteristics, modeling and recent developments of smart materials specially shape memory alloys and smart composites. This field even involves smart fluids and it opens a new era to find new smart materials for eliminating their flaws by combination with other advanced materials. The purpose of this paper is showing the current research coordinate. These issues help to have a technological reference for these materials. At the end, there is specific attention to Nitinols and by experiments is shown that Oliver-Pharr formulation does not cover these material behaviors. These experiments cover some important aspects of Nitinols which have not been... 

    Practical method to predict an upper bound for minimum variance track-to-track fusion

    , Article IET Signal Processing ; Volume 11, Issue 8 , 2017 , Pages 961-968 ; 17519675 (ISSN) Zarei Jalalabadi, M ; Malaek, S. M. B ; Sharif University of Technology
    This study deals with the problem of track-to-track fusion in a sensor network when the correlation terms between the estimates of the agents are unknown. The proposed method offers an upper bound for the optimal minimum variance fusion rule through construction of the correlation terms according to an optimisation scheme. In general, the upper bound filter provides an estimate that is more conservative than the optimal estimate generated by the minimum variance fusion rule, while at the same time is less conservative than one obtained by the widely used covariance intersection method. From the geometrical viewpoint, the upper bound filter results in the inscribed largest volume ellipsoid... 

    3-point RANSAC for fast vision based rotation estimation using GPU technology

    , Article IEEE International Conference on Multisensor Fusion and Integration for Intelligent Systems9 February 2017 ; 2017 , Pages 212-217 ; 9781467397087 (ISBN) Kamran, D ; Manzuri, M. T ; Marjovi, A ; Karimian, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2017
    In many sensor fusion algorithms, the vision based RANdom Sample Consensus (RANSAC) method is used for estimating motion parameters for autonomous robots. Usually such algorithms estimate both translation and rotation parameters together which makes them inefficient solutions for merely rotation estimation purposes. This paper presents a novel 3-point RANSAC algorithm for estimating only the rotation parameters between two camera frames which can be utilized as a high rate source of information for a camera-IMU sensor fusion system. The main advantage of our proposed approach is that it performs less computations and requires fewer iterations for achieving the best result. Despite many... 

    Towards interacting with smarter systems

    , Article Journal of Ambient Intelligence and Humanized Computing ; Volume 9, Issue 1 , February , 2018 , Pages 187-209 ; 18685137 (ISSN) Mostafazadeh Davani, A ; Nazari Shirehjini, A. A ; Daraei, S ; Sharif University of Technology
    Springer Verlag  2018
    The aim of this article is the requirement analysis, design, proof-of-concept implementation and user evaluation of a novel user interface that is specifically developed to support interaction with ambient intelligence systems. The focus of the user interface is rather on interacting with ambient intelligence, a meta system that comes into existence as the result of the coherent behavior and collective intelligence of interconnected smart devices and systems of a domain such as meeting rooms or smart homes. To design the user interface, we conducted an empirical user and task analysis and elaborated requirements, defining the scope of human interaction with ambient intelligence. The captured... 

    Frame-based face emotion recognition using linear discriminant analysis

    , Article 3rd Iranian Conference on Signal Processing and Intelligent Systems, ICSPIS 2017, 20 December 2017 through 21 December 2017 ; Volume 2017-December , December , 2018 , Pages 141-146 ; 9781538649725 (ISBN) Otroshi Shahreza, H ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2018
    In this paper, a frame-based method with reference frame was proposed to recognize six basic facial emotions (anger, disgust, fear, happy, sadness and surprise) and also neutral face. By using face landmarks, a fast algorithm was used to calculate an appropriate descriptor for each frame. Furthermore, Linear Discriminant Analysis (LDA) was used to reduce the dimension of defined descriptors and to classify them. The LDA problem was solved using the least squares solution and Ledoit-Wolf lemma. The proposed method was also compared with some studies on CK+ dataset which has the best accuracy among them. To generalize the proposed method over CK+ dataset, a landmark detector was needed.... 

    In-the-wild no-reference image quality assessment using deep convolutional neural networks

    , Article 5th Iranian Conference on Signal Processing and Intelligent Systems, ICSPIS 2019, 18 December 2019 through 19 December 2019 ; 2019 ; 9781728153506 (ISBN) Otroshi Shahreza, H ; Amini, A ; Behroozi, H ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    With the ever-growing portion of internet traffic associated with multimedia data and the existence of multiple copies of the same content in various forms, it has become vital to measure the quality of the image and video files. In most cases, without access to the original file, the quality shall be assessed solely based on the available file. Specifically, the challenge of no-reference image quality assessment (NR-IQA) is to predict a quality measure for given images in a consistent manner with human perception of quality. Conventional NR-IQA methods try to fit certain distortion models to a given image and quantify the quality. In practice, however, an image is affected by a combination...