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    Adaptive neuro-fuzzy inference system in fuzzy measurement to track association

    , Article Journal of Dynamic Systems, Measurement and Control, Transactions of the ASME ; Volume 132, Issue 2 , 2010 , Pages 1-8 ; 00220434 (ISSN) Dehghani Tafti, A ; Sadati, N ; Sharif University of Technology
    2010
    Abstract
    The main issue in a surveillance environment is the target tracking. The most important concern in this problem is the association of the various measurements with the existing target tracks. The fuzzy c-means data association (FCMDA) algorithm, based on the fuzzy c-means (FCM) algorithm, is an efficient solution for the problem of measurement to track association in a multisensor multitarget environment. It has a high accuracy in measurement to track association when targets are far from each other. However, its accuracy remains low when targets are close to one another. The FCMDA algorithm performance is usually lost in this environment, especially when measurement noise is high. In the... 

    Modified maximum entropy fuzzy data association filter

    , Article Journal of Dynamic Systems, Measurement and Control, Transactions of the ASME ; Volume 132, Issue 2 , 2010 , Pages 1-9 ; 00220434 (ISSN) Dehghani Tafti, A ; Sadati, N ; Sharif University of Technology
    2010
    Abstract
    The problem of fuzzy data association for target tracking in a cluttered environment is discussed in this paper. In data association filters based on fuzzy clustering, the association probabilities of tracking filters are reconstructed by utilizing the fuzzy membership degree of the measurement belonging to the target. Clearly in these filters, the fuzzy clustering method has an important role; better approach causes better precision in target tracking. Recently, by using the information theory, the maximum entropy fuzzy data association filter (MEF-DAF), as a fast and efficient algorithm, is introduced in literature. In this paper, by modification of a fuzzy clustering objective function,... 

    A hybrid fuzzy adaptive tracking algorithm for maneuvering targets

    , Article 2008 IEEE International Conference on Fuzzy Systems, FUZZ 2008, Hong Kong, 1 June 2008 through 6 June 2008 ; 2008 , Pages 1869-1873 ; 10987584 (ISSN) ; 9781424418190 (ISBN) Dehghani Tafti, A ; Sadati, N ; Sharif University of Technology
    2008
    Abstract
    A new hybrid fuzzy adaptive algorithm for tracking maneuvering targets is proposed in this paper. The algorithm is implemented with fuzzy inference system (FIS) and current statistical model and adaptive Altering (CSMAF). The CSMAF algorithm is one of most effective methods for tracking the maneuvering targets. It has a higher precision in tracking the maneuvering targets with larger accelerations while it has a lower precision in tracking the maneuvering targets with smaller acceleration. In the proposed algorithm, to overcome the disadvantage of the CSMAF algorithm, the covariance of process noise CSMAF is adjusted adaptively by the output of a FIS. The input of the FIS is discrepancy of... 

    A novel adaptive tracking algorithm for maneuvering targets based on information fusion by neural network

    , Article EUROCON 2007 - The International Conference on Computer as a Tool, Warsaw, 9 September 2007 through 12 September 2007 ; December , 2007 , Pages 818-822 ; 142440813X (ISBN); 9781424408139 (ISBN) Dehghani Tafti, A ; Sadati, N ; Sharif University of Technology
    2007
    Abstract
    The current statistical model and adaptive filtering (CSMAF) algorithm is one of the most effective methods for tracking the maneuvering targets. However, it is still worthy to investigate the characteristics of the CSMAF algorithm, which has a higher precision in tracking the maneuvering targets with larger accelerations while it has a lower precision in tracking the maneuvering targets with smaller acceleration. In this paper a novel adaptive tracking algorithm for maneuvering targets is proposed. To overcome the disadvantage of the CSMAF algorithm, a simple multi-layer feedforward neural network (NN) is used By introducing NN, two sources of information of the filter are fused while its... 

    Novel adaptive Kalman filtering and fuzzy track fusion approach for real time applications

    , Article 2008 3rd IEEE Conference on Industrial Electronics and Applications, ICIEA 2008, Singapore, 3 June 2008 through 5 June 2008 ; 2008 , Pages 120-125 ; 9781424417186 (ISBN) Dehghani Tafti, A ; Sadati, N ; Sharif University of Technology
    2008
    Abstract
    The track fusion combines individual tracks formed by different sensors. Tracks are usually obtained by Kalman Filter (KF), since it is suitable for real-time application. The KF is an optimal linear estimator when the measurement noise has a Gaussian distribution with known covariance. However, in practice, some of the sensors do not have these properties, and the traditional KF is not an optimal estimator. In this paper, a novel adaptive Kalman filter (NAKF) is proposed. In this approach, the measurement noise covariance is adjusted by using an introduced simple mathematical function of one variable, called the degree of matching (DoM), where it is defined on the basis of covariance... 

    Investigation of Membrane Fouling in Submerged Membrane Electro-Bioreactor (SMEBR) with Iron Electrodes

    , M.Sc. Thesis Sharif University of Technology Dehghani Tafti, Alireza (Author) ; Vosoughi, Manoochehr (Supervisor)
    Abstract
    This thesis presents the results of the performance of a novel technology called submerged membrane electro-bioreactor (SMEBR). The SMEBR treats wastewater by combining membrane filtration, electrokinetic phenomena, and biological processes in one reactor, and improves treatment performance while helping to control membrane fouling. The newly designed SMEBR system was based on applying an intermittent direct current (DC) field between immersed perforated electrodes around a membrane filtration module. The SMEBR system significantly reduced the fouling rate when iron worked as electrodes and an intermittent DC with an operational different mode was applied.
    In Phase 1 of this project,... 

    Design of Line Heating in Creation of Certain Curvature in Sheet Metal

    , M.Sc. Thesis Sharif University of Technology Dehghani Tafti, Mojtaba (Author) ; Assempour, Ahmad (Supervisor)
    Abstract
    Metal sheets are widely used in different industries such as ship building and pressure vessels. One of the most important things in these industries is to create the desired sheets through line heating process. Designing the heating lines in order to get the desired shape with the sufficient accuracy has always been a concern for the engineers in this process. In this research, different methods of designing the heating lines for creating special surfaces are discussed. By integrating the two algorithms called distance based criterion method and angle based criterion method in MATLAB, the heating path and its parameters are defined. These two algorithms can be used in order to predict the... 

    Applications of Sparse Representation in Digital Image Inpainting

    , M.Sc. Thesis Sharif University of Technology Dehghani Tafti, Zahra (Author) ; Babaiezadeh, Massoud (Supervisor)
    Abstract
    Image inpainting is the process of reconstructing lost parts of damaged images based on collected local information, or even general information, as prior knowledge. The image inpainting’s objective is to improve the damaged images, for example restoring missing pixels caused by folding, erasing background’s text in an image, removing watermarks from an image, or editing an image such as eliminating an object or a person from the image. The majority of the image inpainting algorithms approaches the problem by signal restoration from remaining samples or iterative methods to complete the damaged images. Algorithms based on samples, algorithms based on partial differential equations, and... 

    Interaction of Femtosecond Lasers with Molecule

    , M.Sc. Thesis Sharif University of Technology Dehghani Tafti, Zeinab (Author) ; Sadighi Bonabi, Rasul (Supervisor)
    Abstract
    Using field assisted dissociation model and with a classic view the dissociation probability is calculated when it a molecule is exposed with a Ti:sapphire laser with wavenumber of 800nm and the energy of . using gradient optimization method we find a tailored two rectangular laser pulse for controlling the dissociation of C-H bond of . Using classical method reduced the complicacy of solving schrodinger equation. In our optimization method in contrast with the usual controlling method experimental data is not needed and this reduced the controlling costs.

     

    Tolerance Design of Mechanical Parts Considering Degradation and Quality Loss in Manufacturing Process and Operating Conditions

    , M.Sc. Thesis Sharif University of Technology Dehghani Tafti, Mohammad Saleh (Author) ; Khodaygan, Saeed (Supervisor) ; Asempour, Ahmad (Supervisor)
    Abstract
    The tolerance stack-up in mechanical assemblies is closely related to the quality of finished products and to the costs of production. In practice, choosing a large tolerance range will result in performance reduction. On the other hand, with small tolerances considered, production costs will increase. Tolerance allocation is a useful tool to control the dimensional and geometric variables of the product, so design engineers can control the final product quality level, production cost, and other variables. The proposed method for tolerance design considers the effects of degradation and quality loss over time and allocates tolerances so that, the functional key characteristic satisfies, as... 

    Frontal Plane Balance Control of a Biped Robot Based on Human Balancing Strategy

    , M.Sc. Thesis Sharif University of Technology Dehghani Tafti, Mohammad Reza (Author) ; Farahmand, Farzam (Supervisor) ; Hoviattalab, Maryam (Supervisor)
    Abstract
    The capability to control and maintain upright posture is a fundamental requirement for humanoid robots. Although many control algorithms were successfully presented, it seems developing a new controller inspired from human balance strategy would greatly improve performance and reduce energy consumption. To study the control strategy used by human nerves system more precisely, a balancing exercise was designed and implemented. Five human subjects were asked to stand on an unstable tilting board and balance the board. Instantaneous Eulerian angles of body segments of human subjects were captured by utilizing Xsense orientation sensors. A humanoid robot standing on the tilting board was... 

    Bioremediation of Soils Contaminated by Polychlorinated Biphenyls

    , M.Sc. Thesis Sharif University of Technology Dehghani Mohammadabadi, Fatemeh (Author) ; Yaghmaei, Soheila (Supervisor) ; Ghobadi Nejad, Zahra (Co-Supervisor)
    Abstract
    Polychlorinated Biphenyls are a class of organic compounds that are composed of two biphenyl rings attached by 1-10 chlorine atoms. Due to their specific properties, such as physical and chemical stability, flame resistance, and dielectric properties, these compounds are used as dielectric liquids, heat-exchange fluids, hydraulic liquids, plastifiers, and especially as Askarel oil in power plant transformer. Because of their high persistency in the environment, high toxicity, and bioaccumulation in the adipose tissue of humans and animals, their production is banned in most countries, and their use has been limited. There are different methods for detoxification of these compounds, and in... 

    Comparison of Performance of Different Boundary Conditions in Numerical Analysis of Dam-Foundation Interaction
    Under Dynamic Loads

    , M.Sc. Thesis Sharif University of Technology Emadi Tafti, Mohsen (Author) ; Pak, Ali (Supervisor)
    Abstract
    In this study, the performance of different boundary conditions in dynamic analysis of embankment dams, with consideration of dam-foundation interaction, is compared. All of models are in 2D space. The behavior of dam and the foundation are assumed to be linear elastic. Dam is built of compacted clay, whereas three types of soil are considered for foundation: loose, Medium and dense sand. Direct method is used for dam-foundation interaction analysis. We used Finite Element Method (FEM) using 8-node, quadrilateral and isoparametric elements to analyse the models. The incitement is horizontal displacement with different frequencies that is applied to lower boundary of foundation. In addition,... 

    A modeling platform for landslide stability: A hydrological approach

    , Article Water (Switzerland) ; Volume 11, Issue 10 , 2019 ; 20734441 (ISSN) Emadi Tafti, M ; Ataie Ashtiani, B ; Sharif University of Technology
    MDPI AG  2019
    Abstract
    Landslide events are among natural hazards with many fatalities and financial losses. Studies demonstrate that natural factors such as rainfall and human activities such as deforestation are important causes of triggering a landslide. In this study, an integrated two-dimensional slope stability model, SSHV-2D, is developed that considers various aspects of hydrological effects and vegetation impacts on the stability of slopes. The rainfall infiltration and water uptake of roots change the water content of the unsaturated zone. The temporal and spatial distribution of water content is estimated in the hydrological unit of the developed model. The vegetation unit of the model considers... 

    Mesoporous silica nanoparticles (MCM-41) coated PEGylated chitosan as a pH-Responsive nanocarrier for triggered release of erythromycin [electronic resource]

    , Article International Journal of Polymeric Materials and Polymeric Biomaterials ; 2014, Volume 63, Issue 13, Pages 692-697 Pourjavadi, A. (Ali) ; Mazaheri Tehrani, Zahra ; Sharif University of Technology
    Abstract
    A pH-responsive drug delivery system based on core shell structure of mesoporous silica nanoparticle (MSN) and chitosan-PEG copolymer was prepared and characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscope (SEM), and high-resolution transmission microscope (HR-TEM) techniques. In order to improve compatibility MSN and drug, mesoporous nanosilica was modified by 3-aminopropyl triethoxysilane. The release of erythromycin (a macrolide antibiotic) as a model drug was investigated in two pHs, 7.4 and 5.5  

    A 2.5GHz CMOS fully-integrated ΔΣ-controlled fractional-N frequency synthesizer

    , Article Proceedings - 17th International Conference on VLSI Design, Concurrently with the 3rd International Conference on Embedded Systems Design, Mumbai, 5 January 2004 through 9 January 2004 ; Volume 17 , 2004 , Pages 163-167 ; 10639667 (ISSN) Dehghani, R ; Sharif University of Technology
    2004
    Abstract
    The design of a fully-integrated ΔΣ -controlled fractional-N frequency synthesizer is described. Using a dual modulus 64/72 prescaler based on injection locking technique and a novel third order digital ΔΣ modulator, we achieved an extremely low power synthesizer in 2.5GHz band.. Total power dissipation of the frequency synthesizer is less than 6mW at a 1.5V supply. The loop bandwidth is optimized to achieve a -123dBc/Hz phase noise at 3MHz offset frequency. The locking time of the loop is less than 30μs  

    Stability Analysis of Slopes with Inclusion of Hydrological and Vegetation Effects

    , Ph.D. Dissertation Sharif University of Technology Emadi Tafti, Mohsen (Author) ; Ataie Ashtiani, Behzad (Supervisor)
    Abstract
    Landslide is a natural hazard associated with economic losses and fatalities. The geometric of the slope, the soil properties, hydrological factors, and groundwater are important factors that affect the stability of a slope. The landslide investigation is important due to the identification and prevention of damages. Thus, more researchers studies on this subject. The new questions in this field are “how can simulate the vegetation effects in slope stability analysis?” and “what effects do precipitation and infiltration have on landslide triggering?”. Although the classic methods of slope stability analysis provide the initial information for the design, they have limitations in answering... 

    Risk-based Prioritization of Highway Bridge Networks for Seismic Retrofit and Health Monitoring

    , M.Sc. Thesis Sharif University of Technology Noorbala Tafti, Hamid Reza (Author) ; Mahsouli, Mojtaba (Supervisor)
    Abstract
    This thesis presents a probabilistic framework for prioritizing the highway bridge network for seismic retrofitting and structural health monitoring. The basis of this framework is the risk analysis of the bridge network, which includes bridges and the links connecting them in the transportation network. Risk is defined as the probability of exceeding the sum of all losses incurred to the community in the event of a hazard. These losses include the direct economic cost of bridge repairs and damage to vehicles due to bridge failure, the socioeconomic cost of increased travel time for transportation network users, the indirect economic cost of excess fuel consumption and depreciation of... 

    Photocatalytic degradation of vancomycin using titanium dioxide and optimization by central composite design

    , Article International Journal of Environmental Science and Technology ; Volume 19, Issue 9 , 2022 , Pages 8957-8968 ; 17351472 (ISSN) Dehghani, F ; Yousefinejad, S ; Dehghani, M ; Borghei, S. M ; Javid, A. H ; Sharif University of Technology
    Springer Science and Business Media Deutschland GmbH  2022
    Abstract
    Conventional wastewater treatment processes are not completely effective in removing vancomycin. In this study, affecting parameters on vancomycin degradation, such as pH, catalyst, initial vancomycin concentration, temperature, and reaction time were investigated simultaneously during a removal process based on titanium dioxide with ultraviolet irradiation in an aqueous solution. Titanium dioxide was synthesized and characterized using X-ray diffraction and scanning electron microscopy. The average size of the synthesized crystals was 4.7 (± 0.2) nm. Design of experiments was done by a central composite design based on the response surface methodology and multiple linear regression was... 

    Vancomycin removal using TiO2–clinoptilolite/UV in aqueous media and optimisation using response surface methodology

    , Article International Journal of Environmental Analytical Chemistry ; 2022 ; 03067319 (ISSN) Dehghani, F ; Yousefinejad, S ; Dehghani, M ; Borghei, S. M ; Javid, A. H ; Sharif University of Technology
    Taylor and Francis Ltd  2022
    Abstract
    Investigations have shown the traces of antibiotics in surface water, groundwater, wastewater treatment plants, and drinking water. However, conventional wastewater treatment is not entirely effective for vancomycin degradation. Advanced oxidation is one of the most widespread methods of antibiotic degradation in aqueous media. Vancomycin was quantified by high-performance liquid chromatography. The Response Surface Methodology (RSM) based on Central Composite Design (CCD) was used to explore and optimise the effect of the independent variables on vancomycin degradation. Independent variables were as follows: pH (3–11), vancomycin concentration (15–75 mg/L), TiO2–clinoptilolite (25–125 mg in...