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Orientace kamery v reálném čase / Camera Orientation in Real-TimeŽupka, Jiří January 2010 (has links)
This work deals with the orientation of the camera in real-time with a single camera. Offline methods are described and used as a reference for comparison of a real-time metods. Metods work in real-time Monocular SLAM and PTAM methods are there described and compared. Further, paper shows hints of advanced methods whereas future work is possible.
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Prediktivní regulátory s principy umělé inteligence v prostředí MATLAB - B&R / Prediktive controllers with principles of artificial intelligenceMatys, Libor January 2008 (has links)
Master’s thesis deals with problems of predictive control especially Model (Based) Predictive Control (MBPC or MPC). Identifications methods are compared in the first part. Recursive least mean squares algorithm is compared with identification methods based on neural networks. Next parts deal with predictive control. There is described creation MPC with summing element and adaptive MPC. There is also compared fixed setting PSD controller with MPC. Responses on disturbance and changes of parameters of controlled plant are compared. Comparing is made on simulation models in MATLAB/Simulink and on physical model connected to PLC B&R.
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Melizmų sintezė dirbtinių neuronų tinklais / Melisma Synthesis Using Artificial Neural NetworksLeonavičius, Romas 12 January 2007 (has links)
Modern methods of speech synthesis are not suitable for restoration of song signals due to lack of vitality and intonation in the resulted sounds. The aim of presented work is to synthesize melismas met in Lithuanian folk songs, by applying Artificial Neural Networks. An analytical survey of rather a widespread literature is presented. First classification and comprehensive discussion of melismas are given. The theory of dynamic systems which will make the basis for studying melismas is presented and finally the relationship for modeling a melisma with nonlinear and dynamic systems is outlined. Investigation of the most widely used Linear Prediction Coding method and possibilities of its improvement. The modification of original Linear Prediction method based on dynamic LPC frame positioning is proposed. On its basis, the new melisma synthesis technique is presented. Developed flexible generalized melisma model, based on two Artificial Neural Networks – a Multilayer Perceptron and Adaline – as well as on two network training algorithms – Levenberg- Marquardt and the Least Squares error minimization – is presented. Moreover, original mathematical models of Fortis, Gruppett, Mordent and Trill are created, fit for synthesizing melismas, and their minimal sizes are proposed. The last chapter concerns experimental investigation, using over 500 melisma records, and corroborates application of the new mathematical models to melisma synthesis of one performer.
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Melizmų sintezė dirbtinių neuronų tinklais / Melisma Synthesis Using Artificial Neural NetworksLeonavičius, Romas 12 January 2007 (has links)
Modern methods of speech synthesis are not suitable for restoration of song signals due to lack of vitality and intonation in the resulted sounds. The aim of presented work is to synthesize melismas met in Lithuanian folk songs, by applying Artificial Neural Networks. An analytical survey of rather a widespread literature is presented. First classification and comprehensive discussion of melismas are given. The theory of dynamic systems which will make the basis for studying melismas is presented and finally the relationship for modeling a melisma with nonlinear and dynamic systems is outlined. Investigation of the most widely used Linear Prediction Coding method and possibilities of its improvement. The modification of original Linear Prediction method based on dynamic LPC frame positioning is proposed. On its basis, the new melisma synthesis technique is presented. Developed flexible generalized melisma model, based on two Artificial Neural Networks – a Multilayer Perceptron and Adaline – as well as on two network training algorithms – Levenberg- Marquardt and the Least Squares error minimization – is presented. Moreover, original mathematical models of Fortis, Gruppett, Mordent and Trill are created, fit for synthesizing melismas, and their minimal sizes are proposed. The last chapter concerns experimental investigation, using over 500 melisma records, and corroborates application of the new mathematical models to melisma synthesis of one performer.
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Developing Artificial Neural Networks (ANN) Models for Predicting E. Coli at Lake Michigan BeachesMitra Khanibaseri (9045878) 24 July 2020 (has links)
<p>A neural
network model was developed to predict the E. Coli levels and classes in six
(6) select Lake Michigan beaches. Water quality observations at the time of
sampling and discharge information from two close tributaries were used as
input to predict the E. coli. This research was funded by the Indiana Department
of Environmental Management (IDEM). A user-friendly Excel Sheet based tool was
developed based on the best model for making future predictions of E. coli
classes. This tool will facilitate beach managers to take real-time decisions.</p>
<p>The nowcast
model was developed based on historical tributary flows and water quality
measurements (physical, chemical and biological). The model uses experimentally
available information such as total dissolved solids, total suspended solids,
pH, electrical conductivity, and water temperature to estimate whether the E.
Coli counts would exceed the acceptable standard. For setting up this model,
field data collection was carried out during 2019 beachgoer’s season.</p>
<p>IDEM
recommends posting an advisory at the beach indicating swimming and wading are
not recommended when E. coli counts exceed advisory standards. Based on the
advisory limit, a single water sample shall not exceed an E. Coli count of 235 colony
forming units per 100 milliliters (cfu/100ml). Advisories are removed when
bacterial levels fall within the acceptable standard. However, the E. coli
results were available after a time lag leading to beach closures from previous
day results. Nowcast models allow beach managers to make real-time beach
advisory decisions instead of waiting a day or more for laboratory results to
become available.</p>
<p>Using the
historical data, an extensive experiment was carried out, to obtain the
suitable input variables and optimal neural network architecture. The best feed-forward
neural network model was developed using Bayesian Regularization Neural Network
(BRNN) training algorithm. Developed ANN model showed an average prediction
accuracy of around 87% in predicting the E. coli classes. </p>
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Imaging Reflectometry Measuring Thin Films Optical Properties / Imaging Reflectometry Measuring Thin Films Optical PropertiesBěhounek, Tomáš January 2009 (has links)
V této práci je prezentována inovativní metoda zvaná \textit{Zobrazovací Reflektometrie}, která je založena na principu spektroskopické reflektometrie a je určena pro vyhodnocování optických vlastností tenkých vrstev .\ Spektrum odrazivosti je získáno z map intenzit zaznamenaných CCD kamerou. Každý záznam odpovídá předem nastavené vlnové délce a spektrum odrazivosti může být určeno ve zvoleném bodu nebo ve vybrané oblasti.\ Teoretický model odrazivosti se fituje na naměřená data pomocí Levenberg~-~Marquardtova algoritmu, jehož výsledky jsou optické vlastnosti vrstvy, jejich přesnost, a určení spolehlivosti dosažených výsledků pomocí analýzy citlivosti změn počátečních nastavení optimalizačního algoritmu.
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Using AI to improve the effectiveness of turbine performance dataShreyas Sudarshan Supe (17552379) 06 December 2023 (has links)
<p dir="ltr">For turbocharged engine simulation analysis, manufacturer-provided data are typically used to predict the mass flow and efficiency of the turbine. To create a turbine map, physical tests are performed in labs at various turbine speeds and expansion ratios. These tests can be very expensive and time-consuming. Current testing methods can have limitations that result in errors in the turbine map. As such, only a modest set of data can be generated, all of which have to be interpolated and extrapolated to create a smooth surface that can then be used for simulation analysis.</p><p><br></p><p dir="ltr">The current method used by the manufacturer is a physics-informed polynomial regression model that depends on the Blade Speed Ratio (BSR ) in the polynomial function to model the efficiency and MFP. This method is memory-consuming and provides a lower-than-desired accuracy. This model is decades old and must be updated with new state-of-the-art Machine Learning models to be more competitive. Currently, CTT is facing up to +/-2% error in most turbine maps for efficiency and MFP and the aim is to decrease the error to 0.5% while interpolating the data points in the available region. The current model also extrapolates data to regions where experimental data cannot be measured. Physical tests cannot validate this extrapolation and can only be evaluated using CFD analysis.</p><p><br></p><p dir="ltr">The thesis focuses on investigating different AI techniques to increase the accuracy of the model for interpolation and evaluating the models for extrapolation. The data was made available by CTT. The available data consisted of various turbine parameters including ER, turbine speeds, efficiency, and MFP which were considered significant in turbine modeling. The AI models developed contained the above 4 parameters where ER and turbine speeds are predictors and, efficiency and MFP are the response. Multiple supervised ML models such as SVM, GPR, LMANN, BRANN, and GBPNN were developed and evaluated. From the above 5 ML models, BRANN performed the best achieving an error of 0.5% across multiple turbines for efficiency and MFP. The same model was used to demonstrate extrapolation, where the model gave unreliable predictions. Additional data points were inputted in the training data set at the far end of the testing regions which greatly increased the overall look of the map.</p><p><br></p><p dir="ltr">An additional contribution presented here is to completely predict an expansion ratio line and evaluate with CTT test data points where the model performed with an accuracy of over 95%. Since physical testing in a lab is expensive and time-consuming, another goal of the project was to reduce the number of data points provided for ANN model training. Furthermore, strategically reducing the data points is of utmost importance as some data points play a major role in the training of ANN and can greatly affect the model's overall accuracy. Up to 50% of the data points were removed for training inputs and it was found that BRANN was able to predict a satisfactory turbine map while reducing 20% of the overall data points at various regions.</p>
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