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Position and Trajectory Control of a Quadcopter Using PID and LQ ControllersReizenstein, Axel January 2017 (has links)
This thesis describes the work done to implement and develop position and trajectory control of a quadcopter. The quadcopter was originally equipped with sensors and software to estimate and control the quadcopter's orientation, but did not estimate the current position. A GPS module, GPS antenna and a LIDAR have been added to measure the position in three dimensions. Filters have been implemented and developed to estimate the position, velocity and acceleration. Four controllers have been designed that use these estimates: one PID controller and one LQ controller for vertical movement, and a position controller and a trajectory controller for horizontal movement. The position controller maintains a constant position, while the trajectory controller maintains a constant velocity while travelling along a straight line. These position and trajectory controllers calculate the reference angles required to direct the thrust necessary to control the quadcopter's movement. Additionally, an algorithm has been developed to decrease overshoot by predicting future trajectories. These controllers have proven to be successful at controlling the quadcopter's position in all three dimensions, both in practice during outdoor flight and in simulations.
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Efficient and robust partitioned solution schemes for fluid-structure interactionsBogaers, Alfred Edward Jules January 2015 (has links)
Includes bibliographical references / In this thesis, the development of a strongly coupled, partitioned fluid-structure interactions (FSI) solver is outlined. Well established methods are analysed and new methods are proposed to provide robust, accurate and efficient FSI solutions. All the methods introduced and analysed are primarily geared towards the solution of incompressible, transient FSI problems, which facilitate the use of black-box sub-domain field solvers. In the first part of the thesis, radial basis function (RBF) interpolation is introduced for interface information transfer. RBF interpolation requires no grid connectivity information, and therefore presents an elegant means by which to transfer information across a non-matching and non-conforming interface to couple finite element to finite volume based discretisation schemes. The transfer scheme is analysed, with particular emphasis on a comparison between consistent and conservative formulations. The primary aim is to demonstrate that the widely used conservative formulation is a zero order method. Furthermore, while the consistent formulation is not provably conservative, it yields errors well within acceptable levels and converges within the limit of mesh refinement. A newly developed multi-vector update quasi-Newton (MVQN) method for implicit coupling of black-box partitioned solvers is proposed. The new coupling scheme, under certain conditions, can be demonstrated to provide near Newton-like convergence behaviour.
The superior convergence properties and robust nature of the MVQN method are shown in comparison to other well-known quasi-Newton coupling schemes, including the least squares reduced order modelling (IBQN-LS) scheme, the classical rank-1 update Broyden's method, and fixed point iterations with dynamic relaxation. Partitioned, incompressible FSI, based on Dirichlet-Neumann domain decomposition solution schemes, cannot be applied to problems where the fluid domain is fully enclosed. A simple example often provided in the literature is that of balloon inflation with a prescribed inflow velocity. In this context, artificial compressibility (AC) will be shown to be a useful method to relax the incompressibility constraint, by including a source term within the fluid continuity equation. The attractiveness of AC stems from the fact that this source term can readily be added to almost any fluid field solver, including most commercial solvers. AC/FSI is however limited in the range of problems it can effectively be applied to. To this end, the combination of the newly developed MVQN method with AC/FSI is proposed. In so doing, the AC modified fluid field solver can continue to be treated as a black-box solver, while the overall robustness and performance are significantly improved. The study concludes with a demonstration of the modularity offered by partitioned FSI solvers. The analysis of the coupled environment is extended to include steady state FSI, FSI with free surfaces and an FSI problem with solid-body contact.
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Empirical modeling of the thermal systems in an apartment : A study of the relationship between household electricity consumption and indoor temperatureWallentinsson, Måns, Jacob, Rutfors January 2020 (has links)
In this study, linear and non-linear models were trained on real data to mimic the relationship between household electricity consumption and indoor temperature, in the rooms of an apartment in downtown Stockholm. The aim was to better understand this relationship and to distinguish any divergence between the different rooms. With data from two weeks of measurements, the models proved to perform well when tested on validation data for almost all rooms, only showing performance dips for the middle room. A noticeable correlation between the electricity consumption and the indoor temperature was observed for all rooms except the bedroom. However, the benefits of using this information to predict the indoor temperature are limited and differ between the rooms. The household electricity consumption primarily brought beneficial information to the kitchen models, where most of the heat generating appliances were located. It was found that linear models were sufficient to represent the thermal systems of the rooms, performing equally well and often better than non-linear models.
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Contribution à l'évaluation opérationnelle des systèmes biométriques multimodaux / Contribution to the operational evaluation of multimodal biometric systemsCabana, Antoine 28 November 2018 (has links)
Le développement et la multiplication de dispositifs connectés, en particulier avec les \textit{smartphones}, nécessitent la mise en place de moyens d'authentification. Dans un soucis d'ergonomie, les industriels intègrent massivement des systèmes biométrique afin de garantir l'identité du porteur, et ce afin d'autoriser l'accès à certaines applications et fonctionnalités sensibles (paiements, e-banking, accès à des données personnelles : correspondance électronique..). Dans un soucis de garantir, une adéquation entre ces systèmes d'authentification et leur usages, la mise en œuvre d'un processus d'évaluation est nécessaire.L'amélioration des performances biométriques est un enjeux important afin de permettre l'intégration de telles solutions d'authentification dans certains environnement ayant d'importantes exigences sur les performances, particulièrement sécuritaires. Afin d'améliorer les performances et la fiabilité des authentifications, différentes sources biométriques sont susceptibles d'être utilisées dans un processus de fusion. La biométrie multimodale réalise, en particulier, la fusion des informations extraites de différentes modalités biométriques. / Development and spread of connected devices, in particular smartphones, requires the implementation of authentication methods. In an ergonomic concern, manufacturers integrates biometric systems in order to deal with logical control access issues. These biometric systems grant access to critical data and application (payment, e-banking, privcy concerns : emails...). Thus, evaluation processes allows to estimate the systems' suitabilty with these uses. In order to improve recognition performances, manufacturer are susceptible to perform multimodal fusion.In this thesis, the evaluation of operationnal biometric systems has been studied, and an implementation is presented. A second contribution studies the quality estimation of speech samples, in order to predict recognition performances.
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On the Topic of Unconstrained Black-Box Optimization with Application to Pre-Hospital Care in Sweden : Unconstrained Black-Box OptimizationAnthony, Tim January 2021 (has links)
In this thesis, the theory and application of black-box optimization methods are explored. More specifically, we looked at two families of algorithms, descent methods andresponse surface methods (closely related to trust region methods). We also looked at possibilities in using a dimension reduction technique called active subspace which utilizes sampled gradients. This dimension reduction technique can make the descent methods more suitable to high-dimensional problems, which turned out to be most effective when the data have a ridge-like structure. Finally, the optimization methods were used on a real-world problem in the context of pre-hospital care where the objective is to minimize the ambulance response times in the municipality of Umea by changing the positions of the ambulances. Before applying the methods on the real-world ambulance problem, a simulation study was performed on synthetic data, aiming at finding the strengths and weaknesses of the different models when applied to different test functions, at different levels of noise. The results showed that we could improve the ambulance response times across several different performance metrics compared to the response times of the current ambulancepositions. This indicates that there exist adjustments that can benefit the pre-hospitalcare in the municipality of Umea. However, since the models in this thesis work find local and not global optimums, there might still exist even better ambulance positions that can improve the response time further. / I denna rapport undersöks teorin och tillämpningarna av diverse blackbox optimeringsmetoder. Mer specifikt så har vi tittat på två familjer av algoritmer, descentmetoder och responsytmetoder (nära besläktade med tillitsregionmetoder). Vi tittar också på möjligheterna att använda en dimensionreduktionsteknik som kallas active subspace som använder samplade gradienter för att göra descentmetoderna mer lämpade för högdimensionella problem, vilket visade sig vara mest effektivt när datat har en struktur där ändringar i endast en riktning har effekt på responsvärdet. Slutligen användes optimeringsmetoderna på ett verkligt problem från sjukhusvården, där målet var att minimera svarstiderna för ambulansutryckningar i Umeå kommun genom att ändra ambulanspositionerna. Innan metoderna tillämpades på det verkliga ambulansproblemet genomfördes också en simuleringsstudie på syntetiskt data. Detta för att hitta styrkorna och svagheterna hos de olika modellerna genom att undersöka hur dem hanterar ett flertal testfunktioner under olika nivåer av brus. Resultaten visade att vi kunde förbättra ambulansernas responstider över flera olika prestandamått jämfört med responstiderna för de nuvarande ambulanspositionerna. Detta indikerar att det finns förändringar av positioneringen av ambulanser som kan gynna den pre-hospitala vården inom Umeå kommun. Dock, eftersom modellerna i denna rapport hittar lokala och inte globala optimala punkter kan det fortfarande finnas ännu bättre ambulanspositioner som kan förbättra responstiden ytterligare.
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A Comparison of Second Grade Children's Learning Curves on School Tasks with Their Respective Performances on the "Black Box Test of Learning Ability"Knox, Robert Stephen 01 May 1975 (has links)
This study investigated the usefulness of the Black Box Test of Learning Ability as an indicator of children's performance on math and writing tasks. Twelve second grade students, seven to eight years of age, demonstrated naivete on both tasks and were subsequently individually administered the learning test. The subjects were divided into two groups, and each group received a different task presentation order. Composite scores were derived for all subjects and tasks, and individual learning curves were compared.
The combined Black Test score produced a significantly high correlate to math (rho = .733) and writing (rho = .841) than either the paired associate or sequential learning tasks alone. Although the length of the learning curve of the BBT was indicative of the learning curve lengths for each school task, trial by trial learning curve comparisons were less reliable. Analysis of these data suggested that the method of instruction (i.e., the amount of attempted practice and appropriate feedback) was the major factor correlating the Black Box Test to each school task. It was suggested that the most useful assessment of "learning ability" would employ a behavioral sample of the task itself, rather than utilize a correlated activity.
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Costly Black-Box Optimization with GTperform at Siemens Industrial TurbomachineryMalm, André January 2022 (has links)
The simulation program GTperform is used to estimate the machine settings from performance measurements for the gas turbine model STG-800 at Siemens Industrial Turbomachinery in Finspång, Sweden. By evaluating different settings within the program, the engineers try to estimate the one that generatesthe performance measurement. This procedure is done manually at Siemens and is very time-consuming. This project aims to establish an algorithm that automatically establishes the correct machine setting from the performance measurements. Two algorithms were implemented in Python: Simulated Annealing and Gradient Descent. The algorithms analyzed two possible objective functions, and objective were tested on three gas turbines located at different locations. The first estimated the machine setting that generated the best fit to the performance measurements, while the second established the most likely solution for the machine setting from probability distributions. Multiple simulations have been run for the two algorithms and objective functions to evaluate the performances. Both algorithms successfully established satisfactory results for the second objective function. The Simulated Annealing, in particular, established solutions with a lower spread compared to Gradient Descent. The algorithms give a possibility to automatically establish the machine settings for the simulation program, reducing the work for the engineers.
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Of Mice and Men: The Development and Analysis of a Black Box ProductionBrown, Morgan Lorene 12 December 2019 (has links)
No description available.
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Automatisierte Erstellung von Blackbox-Tests am Beispiel von StromverteilerleistenKilian, Wolfgang, Pätz, Christian, Heinkel, Ulrich 15 September 2015 (has links)
Um die Zuverlässigkeit von intelligenten Stromverteilerleisten zu überprüfen, wird eine Methode entwickelt, die es ermöglicht, weitestgehend automatisierte und herstellerunabhängige Messergebnisse aufzunehmen, zu vergleichen und zu bewerten. Die Betrachtung der Stromverteilerleisten erfolgt hierbei als Blackbox, welche durch einen möglichst vollumfänglichen Satz an Eigenschaften beschrieben wird. Der zur Messung notwendige Testplan wird aus dieser Beschreibung der Eigenschaften automatisch generiert und kann dann getrennt im Labor ausgeführt werden. Dabei wird eine durchgehende Dokumentation des Messablaufs und der Umgebungsbedingungen sichergestellt. Im Nachgang ist eine Analyse der Messergebnisse sowie eine teilautomatisierte Protokollerstellung möglich.
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Quantum Algorithms For: Quantum Phase Estimation, Approximation Of The Tutte Polynomial And Black-box StructuresAhmadi, Hamad 01 January 2012 (has links)
In this dissertation, we investigate three different problems in the field of Quantum computation. First, we discuss the quantum complexity of evaluating the Tutte polynomial of a planar graph. Furthermore, we devise a new quantum algorithm for approximating the phase of a unitary matrix. Finally, we provide quantum tools that can be utilized to extract the structure of black-box modules and algebras. While quantum phase estimation (QPE) is at the core of many quantum algorithms known to date, its physical implementation (algorithms based on quantum Fourier transform (QFT) ) is highly constrained by the requirement of high-precision controlled phase shift operators, which remain difficult to realize. In the second part of this dissertation, we introduce an alternative approach to approximately implement QPE with arbitrary constantprecision controlled phase shift operators. The new quantum algorithm bridges the gap between QPE algorithms based on QFT and Kitaev’s original approach. For approximating the eigenphase precise to the nth bit, Kitaev’s original approach does not require any controlled phase shift operator. In contrast, QPE algorithms based on QFT or approximate QFT require controlled phase shift operators with precision of at least Pi/2n. The new approach fills the gap and requires only arbitrary constant-precision controlled phase shift operators. From a physical implementation viewpoint, the new algorithm outperforms Kitaev’s approach. iii The other problem we investigate relates to approximating the Tutte polynomial. We show that the problem of approximately evaluating the Tutte polynomial of triangular graphs at the points (q, 1/q) of the Tutte plane is BQP-complete for (most) roots of unity q. We also consider circular graphs and show that the problem of approximately evaluating the Tutte polynomial of these graphs at the point (e 2πi/5 ,e−2πi/5 ) is DQC1-complete and at points (q k , 1 + 1−q−k (q 1/2−q−1/2) 2 ) for some integer k is in BQP. To show that these problems can be solved by a quantum computer, we rely on the relation of the Tutte polynomial of a planar G graph with the Jones and HOMFLY polynomial of the alternating link D(G) given by the medial graph of G. In the case of our graphs the corresponding links are equal to the plat and trace closures of braids. It is known how to evaluate the Jones and HOMFLY polynomial for closures of braids. To establish the hardness results, we use the property that the images of the generators of the braid group under the irreducible Jones-Wenzl representations of the Hecke algebra have finite order. We show that for each braid b we can efficiently construct a braid ˜b such that the evaluation of the Jones and HOMFLY polynomials of their closures at a fixed root of unity leads to the same value and that the closures of ˜b are alternating links. The final part of the dissertation focuses on finding the structure of a black-box module or algebra. Suppose we are given black-box access to a finite module M or algebra over a finite ring R, and a list of generators for M and R. We show how to find a linear basis and structure constants for M in quantum poly(log |M|) time. This generalizes a recent quantum algorithm of Arvind et al. which finds a basis representation for rings. We then show that iv our algorithm is a useful primitive allowing quantum computers to determine the structure of a finite associative algebra as a direct sum of simple algebras. Moreover, it solves a wide variety of problems regarding finite modules and rings. Although our quantum algorithm is based on Abelian Fourier transforms, it solves problems regarding the multiplicative structure of modules and algebras, which need not be commutative. Examples include finding the intersection and quotient of two modules, finding the additive and multiplicative identities in a module, computing the order of an module, solving linear equations over modules, deciding whether an ideal is maximal, finding annihilators, and testing the injectivity and surjectivity of ring homomorphisms. These problems appear to be exponentially hard classically.
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