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Řízek, Matěj. "Galerie." Master's thesis, Vysoké učení technické v Brně. Fakulta výtvarných umění, 2014. http://www.nusl.cz/ntk/nusl-232416.
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It is a half-material imaginary architecture that guides the movement of a viewer. Or takes place to stop the viewer in me creating environment. Construction visually "disturbs" the space to a minimum, but the movement of the viewer will be completely different.
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Samaritter, Rosemarie. "Inside the mirror : effects of attuned dance-movement intervention on interpersonal engagement as observed in changes of movement patterns in children and adolescents with autism spectrum disorder." Thesis, University of Hertfordshire, 2016. http://hdl.handle.net/2299/16572.
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The research presented in this thesis is an explorative study into the basic concepts and the effects of dance movement psychotherapy (DMP) intervention on the attunement behaviours of children and adolescents with autism spectrum disorders (ASD). From a retrospective analysis of positively evaluated single cases of DMP with ASD participants, movement markers of interpersonal relating behaviours have been formulated in terms of Social Engagement and Attunement Movement (SEAM) behaviours. These were organised into an observation scale, and used subsequently to generate nominal observation data on the behaviours of a small sample of children with ASD. Evaluation with the SEAM observation scale yielded a significant increase of SEAM behaviours in the course of the dance therapy. Retrospective analysis of the actions of the therapist throughout four single cases of DMP with ASD participants yielded a specific approach that was described as Shared Movement Approach (SMA). SMA has been specified as an improvisation based method of DMP that takes the child's interpersonal attunement and engagement behaviours as cues for the therapist to accommodate her interventions, so that the child's interpersonal relating behaviours are facilitated and supported. Through her kinaesthetically informed interventions the DMP therapist contributes to an increase of interpersonal engagement and attunement by the ASD participant from within the shared movement actions. The SEAM observation scale was explored on conceptual clarity and consistency in a group of independent movement analysts, and interrater agreement was used as an indication of its contents validity. An interval rating procedure with the SEAM scale yielded the best results on interrater agreement as expressed in Cohen's kappa. The Shared Movement Approach and the SEAM observation scale were then tested for replication of outcome on SEAM behaviours within four repeated single subject cases in a pilot study in a Dutch outpatient clinical setting. The outcome monitoring yielded the replication of increase of interpersonal relating behaviours as measured with the SEAM observation scale. Within subject therapy outcomes, although diverse in their individual profiles, were found to be significant when analysed with non-parametric tests. Group averages showed a significant increase of SEAM behaviours. The effects beyond therapy were evaluated with the somatic and social sub-scales of the Child Behaviour Checklist (CBCL) and the Social Responsiveness Scale (SRS), showing individual differences and a significant problem reduction on average. The outcomes as experienced by the juvenile participants were evaluated with the somatic and social sub-scales of the Youth Self Report (YSR), which on average showed a significant decrease of experienced social and somatic problems. The results obtained are discussed in view of current theories on experiential approaches and concepts for psychotherapy with an ASD population.
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Putrino, David. "Single unit and correlated neural activity observed in the cat motor cortex during a reaching movement." University of Western Australia. School of Medicine and Pharmacology, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0124.
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[Truncated abstract] The goal of this research was to investigate some of the ways that neurons located in the primary motor cortex (MI) code for skilled movement. The task-related and temporally correlated spike activity that occurred during the performance of a goal-directed reaching and retrieval task invloving multiple motion elements and limbs was evaluated in cats. The contributions made by different neuronal subtypes loctaed in MI (which were identified based upon extracellular spiking features0 to the coding of movement was also investigated. Spike activity was simulateously recorded from microelectrodes that were chronically implanted into the motor cortex of both cerebral hemispheres. Task-related neurons modulated their activity during the reaching and retrieval movements of one forelimb, or the postural reactions of the contralateral forelimb and ipsilateral hindlimb. Spike durations and baseline firing rates of neurons were used to distinguish between putative excitatory (Regular Spiking; RS) and inhibitory (Fast Spiking; FS) neurons in the cortex. Frame by frame video analysis of the task was used to subdivide each task trial into stages (e.g. premovement, reach, withdraw and feed) and relate modulations in neural activity to the individual task stages. Task-related neurons were classified as either narrowly tuned or broadly tuned depending on whether their activity modulated during a single task stage or more than one stage respectively. Recordings were made from 163 task-related neurons, and temporal correlations in the spike activity of simultaneously recorded neurons were identified using shuffle corrected cross-correlograms on 662 different neuronal pairs.... The results of this research suggest that temporally correlated activity may reflect the activation of intracortical and callosal connections between a variety of efferent zones involved in task performance, playing a role in the coordination of muscles and limbs during motor tasks. The differences in the patterns of task-related activity, and in the incidence of significant neuronal interactions that were observed between the RS and FS neuronal populations implies that they make different contributions to the coding of movement in MI.
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Corcoran, Briana Christine. "Duration and distance of hyoid bone movement as observed by ultrasound: The influences of flavor and nectar-thick consistency." Miami University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=miami1303160299.
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Harjung, Anna Joy. "The Effects of the Evangelical Reformation Movement on Jane Austen and Charlotte Bronte as Observed in Mansfield Park and Jane Eyre." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/93256.
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This thesis attempts to clarify how the authors incorporated their theological beliefs in their writing to more clearly discover, although modern audiences often enjoy both authors, why Charlotte Bronte was unimpressed with Jane Austen. The thesis is an examination of the ways in which Jane Austen and Charlotte Bronte interact with the Evangelical Reformation within the Anglican Church in their novels Mansfield Park and Jane Eyre, respectively. Both authors, as daughters of Anglican clergymen, were aware of and influenced by the movement, but at varying degrees. This project begins with a brief explanation of the state of the Anglian Church and beginnings of the Evangelical Reformation. The thesis then examines George Austen's influence on his daughter and the characters and text of Mansfield Park to observe the ways in which traditional Anglicanism and tenets of Evangelicalism are discussed in the novel, revealing more clearly where Austen's personal beliefs aligned. Similarly, the project then analyzes Patrick Bronte's influence on Charlotte Bronte and evaluates the characters and text of Jane Eyre to mark the significance of the Evangelical movement on Charlotte Bronte. After studying these works and religious components of their lives, the thesis argues that Austen's traditionally Anglican subtlety with the subject of religion did not appeal to Bronte's passion for the subject, clearly inspired by the Evangelical Reformation.Master of Arts
Charlotte Brontë was unimpressed with the writing of Jane Austen, which is surprising as the audience for one author usually also enjoys the other author as well. Although the specific reason for Brontë’s distaste for Austen is unknown, this thesis proposes that Brontë disagreed with how Austen portrayed Evangelicalism. Both Brontë and Austen were Anglican clergymen’s daughters, and they both grew up with an awareness of the Evangelical Reformation occurring in the Anglican Church. Brontë was influenced by the movement more, which this thesis shows after first outlining the Evangelical Reformation, exploring Austen’s relationship with it and how it appears in Mansfield Park, and then examining Brontë’s relationship with the Reformation and how it appears in Jane Eyre as well. This thesis contains brief historical and biographical sketches of the authors and their families, literary examinations of the novels Mansfield Park and Jane Eyre to study how the authors interacted with the Evangelical ideals, and an analysis that looks at faith in these two novels in a comparative way to explain why Brontë might have disagreed with and therefore disliked Austen’s writing.
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Ruston, Sally A. "Movements of the cervical spine observed by diagnostic ultrasound." Thesis, University of Strathclyde, 1988. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21326.
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An investigation was undertaken to ascertain if standard diagnostic ultrasound equipment was capable of imaging the cervical spine and observing intersegmental motion. Cervical spine anatomy was reviewed with particular attention paid to the location and structure of the ligaments, fascia and articular structures of the region. A real-time B-scanner and 5MHz probe was selected for the project. Using a model spine within a waterbath, experience in image collection and interpretation was gained. The axial and lateral resolution of the scanner was tested. The ability of the scanner to measure a known distance using its caliper function was tested against other methods of measurement. Peripheral joints were scanned with ultrasound and were X-rayed. A set distance on both of the images was measured to see if the two methods were comparable. In vivo scanning of the neck revealed two positions for the probe which were the most useful. The body type of the patient was important to the quality of the scan achieved. Muscular or necks with much adipose tissue would produce poor quality scans. It was possible to image the laminae and the vertebra in transverse section. The motion between laminae and the motion of the vertebra as seen in the transverse view was possible to observe. The quantification of motion still requires attention.
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Olsen, Gunnhild Konstanse Hoff. "Nonlinear Observers for Parametric Roll." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for teknisk kybernetikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18915.
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Parametric roll resonance is a dangerous resonance phenomenon affecting several kinds of ships, such as cruise ships, fishing vessels and container ships. In a worst case scenario parametric roll resonance may lead to roll angles of up to 50 degrees, capsizing of the vessel, or damage of goods and ship for tens of millions of dollars, citep{Ginsberg1998}.Accurate equations in the model for the ship motion are important because they are directly related to the observer design. There has been done allot of mathematical investigations on the problem. In this work, we use a standard model for parametric roll, and express it in state-space form. We establish an augmented state-space model by adding wave-induced forces to the nonlinear state-space model.We revise Lie Derivatives, and use an observability check for nonlinear systems, to derive conditions for nonlinear observability of our system.A Matlab/Simulink model is implemented, and shows that the state space modelis good for simulation of a ship exhibiting parametric roll.The main goal of this thesis has been to investigate different observers for state estimation of a ship exhibiting parametric roll. The wave encounter frequency is estimated by implementing an extended Kalman filter, and in turn an unscented Kalman filter. By comparing the two filters, we conclude that the unscented Kalman filter has better empirical results for estimation of the states of a ship in parametric roll resonance condition. Also attention has been paid to estimation of the direction of the incoming waves.In this thesis the wave direction has been estimated by implementing an extended Kalman filter, and consequently by implementing speed and heading controllers.
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Henningsson, Johan. "Fund managers as cultured observers /." Västerås : School of Sustainable Development of Society and Technology, Mälarddalen University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-1580.
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Haskara, Ibrahim. "Sliding mode controllers and observers." Connect to resource, 1996. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1157562285.
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Brody, Ross Paul. "On The Stochastic Behavior of Brownian Particles in Potential Wells, as Observed with Optical Traps." Fogler Library, University of Maine, 2008. http://www.library.umaine.edu/theses/pdf/BrodyRP2008.pdf.
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Cooper, Lindsey. "Observer performance and eye movements in CT and MR multisectional imagery of stroke." Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/8371.
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Worldwide, radiology continues to evolve. Not only do imaging techniques advance and become more sophisticated, but factors affecting human health change with every decade. The continued advancement of medical images (their acquisition and interpretation) puts a strain on medical specialists, even before individual patient needs are considered. Factors that influence the ability of the reader to deliver patient needs depend on not only the image, but also the readers' level of experience and expertise. Medical image acquisition, accuracy and interpretation have a hugely important role to play in patient safety. In neurology, referred patients are most frequently sent for computed tomography (CT) and magnetic resonance (MR) imaging of the brain to shed light on the origin and impact of disease. Whilst most observer performance studies focus on screening and detection of a few abnormalities in a non-diseased population, the diseases of 'older-age' are often neglected and treated reactively i.e. when a multitude of signs and symptoms appear, not necessarily as a preventive measure. Owing to the difficulty of measuring performance and the nature of expert interpretation when the technology itself is changing; neuroradiology has not been considered extensively from an observer performance perspective and studies concerning visual search in this area are very thin on the ground. Stroke is the focus of inquiry here for many reasons, but predominantly because urgent imaging of patients with quick feedback of image findings can reduce disability and save lives. If a further 10% of acute stroke patients received thrombolytic therapy within 3 hours of onset, over 1,000 people would regain independence per annum rather than rapidly deteriorate (DoH, 2006). Once treatment is administered and followed up effectively, patients can benefit from a further 5-10 years of life (Indredavik, 1999; DoH, 2007). The benefits of further treatment within this population are known. What isn't known is whether experts make errors of judgement within this clinical area, even if access to healthcare is increased.
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Ajzenman, Heather. "Binocular vision skills in human observers /." South Hadley, Mass. : [s.n.],, 2008. http://ada.mtholyoke.edu/setr/websrc/pdfs/www/2008/293.pdf.
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Saunders, Aidan Cyril Giles. "Process monitoring and non-linear observers." Thesis, University of Newcastle Upon Tyne, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308921.
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Babaali, Mohamed. "Switched Linear Systems: Observability and Observers." Diss., Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-04122004-073020/unrestricted/babaali%5Fmohamed%5F200405%5Fphd.pdf.
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Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2004.Verriest, Erik, Committee Member ; Wardi, Yorai, Committee Member ; Yezzi, Anthony, Committee Member ; Wang, Yang, Committee Member ; Egerstedt, Magnus, Committee Chair. Vita. Includes bibliographical references (leaves 80-85).
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Kuhn, Robin Merritt Rosales-Ruiz Jesus. "Assessing the stimulus control of observers." [Denton, Tex.] : University of North Texas, 2009. http://digital.library.unt.edu/ark:/67531/metadc12146.
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Misawa, Eduardo Akira. "Nonlinear state estimation using sliding observers." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/14549.
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Ifqir, Sara. "Interval observers for switched dynamical systems." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLE034.
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Les systèmes dynamiques à commutation sont particulièrement adaptés pour la représentation de la dynamique de nombreux processus et systèmes réels. De fait, la synthèse d'observateurs d'état pour cette classe de systèmes a suscité un intérêt croissant, auprès des chercheurs, au cours des dernières décennies. Cette thèse a pour objectif le développement de méthodologies générales d'estimation d'état robuste pour les systèmes dynamiques à commutation présentant des incertitudes paramétriques, des perturbations externes et/ou des bruits de mesure. Les méthodologies proposées sont fondées sur les approches dites ensemblistes où seules les bornes supérieures et inférieures des variables incertaines sont requises. La présente thèse contribue et résout le problème de l'estimation par intervalle pour les systèmes à commutation en utilisant deux paradigmes : i) Les observateurs par intervalle basés sur la théorie des systèmes coopératifs : où de nouvelles structures d'observateurs par intervalle sont introduites et démontrent certains avantages par rapport aux observateurs classiques. Les conditions suffisantes de stabilité et de coopérativité de l'erreur d'estimation sont fournies sous forme d'inégalités matricielles linéaires (LMI) obtenues en combinant la théorie de Lyapunov et le concept de stabilité entrée-état. Afin d'améliorer la robustesse de l'estimation, une borne supérieure sur l'erreur est garantie et optimisée pour une meilleure précision. ii) Les observateurs par intervalle basés sur la théorie des ensembles : Dans un premier temps, les observateurs par commutation basés sur une caractérisation des bornes de l'erreur d'estimation sont proposés. Ensuite, une nouvelle approche d'estimation d'état zonotopique basée sur la minimisation du rayon du zonotope est développée. Cette méthode repose sur la résolution d'un problème d'optimisation sous contraintes LMIs. Les contributions susmentionnées ont été appliquées à l'estimation d'état et à la détection de défauts dans la dynamique latérale des véhicules. Les algorithmes proposés sont testés sur des données acquises avec des véhicules instrumentés afin de démontrer leur pertinence et leur efficacitéConsidering that many processes and systems in real world applications can be modeled as switched systems, observers synthesis for this class of systems has received a growing interest in the last decades. This thesis intends to provide some contributions to the state-of-the-art in the field of robust state estimation for Switched Dynamical Systems subject to unknown parameters, external disturbances and/or measurement noise. One of the main feature of this dissertation regarding the available literature is that, no statistical evaluation of uncertainties is needed, only the knowledge of the interval boundaries to which these latter belong is required. The proposed methodologies are based on the so-called set-based approaches which provide an estimate of the set of admissible values of the state vector at each time-instant. The present thesis contributes and solves the problem of robust state bounding estimation using two paradigms which are: i) Interval Observer techniques based on cooperative system theory: where new interval observer structures are introduced and shown to have certain advantages over the classical interval observers when studying robustness and cooperativity issues. Sufficient conditions for proving the stability and cooperativity of the interval observer estimation error are provided in terms of Linear Matrix Inequalities (LMIs) constraints obtained using a combination of Lyapunov theory and Input-to-State Stability concept. In order to enhance the estimation accuracy and robustness, an explicit bound of the interval error is guaranteed and optimized for better estimation precision. ii) Set-membership observer techniques based on set theory: where switched observers based on interval characterization of the estimation error are proposed first. Next, new zonotopic state estimation approach based on minimizing the radius of the zonotope is developed. In this spirit, new method leading to the resolution of an optimization problem in the form of LMIs has been proposed. The above-mentioned contributions have been applied to state estimation and Fault Detection in Vehicle Lateral Dynamics. Application to real data recorded with a prototype equipped vehicle demonstrates the relevance and efficiency of the proposed approaches
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Chen, De-Shiou. "Sliding mode observers for automotive alternator." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1384448652.
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Kuhn, Robin Merritt. "Assessing the Stimulus Control of Observers." Thesis, University of North Texas, 2009. https://digital.library.unt.edu/ark:/67531/metadc12146/.
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The science of behavior analysis relies heavily on direct observation. Human observers are typically used to measure behavior in applied settings. Although the use of human observers is beneficial in many regards, it also presents challenges. Of primary concern is the extent to which the data generated by observers actually corresponds to the behavioral events of interest, and the implications this may have in terms of replication. This study assessed the effects that labels, definitions, and examples and non-examples of two different modalities had on observer accuracy, consistency, and agreement. Results showed that current practices in observer training may require refinement to ensure high observer accuracy, consistency, and agreement. Suggestions for how to improve the desired stimulus control of observers are provided.
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Brand, Jonathan Frieman. "Staging Liver Fibrosis with Statistical Observers." Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/612941.
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Chronic liver disease is a worldwide health problem, and hepatic fibrosis (HF) is one of the hallmarks of the disease. Pathology diagnosis of HF is based on textural change in the liver as a lobular collagen network that develops within portal triads. The scale of collagen lobules is characteristically on order of 1mm, which close to the resolution limit of in vivo Gd-enhanced MRI. In this work the methods to collect training and testing images for a Hotelling observer are covered. An observer based on local texture analysis is trained and tested using wet-tissue phantoms. The technique is used to optimize the MRI sequence based on task performance. The final method developed is a two stage model observer to classify fibrotic and healthy tissue in both phantoms and in vivo MRI images. The first stage observer tests for the presence of local texture. Test statistics from the first observer are used to train the second stage observer to globally sample the local observer results. A decision of the disease class is made for an entire MRI image slice using test statistics collected from the second observer. The techniques are tested on wet-tissue phantoms and in vivo clinical patient data.
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Sundt, Tine Charlotte. "Speed Observers for Mechanical Systems and Vehicles." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for teknisk kybernetikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18771.
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The velocity observer in Wondergem et al. [2011] ("the Wondergem Observer") and the velocity observer in Stamnes et al. [2011] ("the Stamnes Observer") are evaluated and compared for a ship model given in Wondergem et al. [2011]. The former observer has shown to be uniformly semi-globally exponentially stable. The latter observer has proven to be uniformly globally asymptotically stable and semi-globally exponentially stable when certain requirements are satisfied. However, due to a non-linear damping term in the ship model, the Stamnes Observer only meets the conditions for uniformly semi-globally exponentially stability.The two observers have shown different convergence properties. The Wondergem Observer has a large overshoot during the settling period, then follows the reference robustly. The Stamnes Observer has a first order system behaviour and can become underdamped in the position convergence. Both observers show similar behaviour when considering a bias in the system equations. However, the run time for the Stamnes observer when simulating on a desktop computer is one to two orders of magnitude longer than for the Wondergem Observer.From the evaluations in this thesis, the Wondergem Observer has shown to be the best choice for the given ship model. It is more robust than the Stamnes Observer, it does not have a lower degree of stability as first implied, and it has a much simpler structure.
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Regoli, Manuel. "Analysis of Flux Observers for Brushless Machines." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
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In this thesis the observation of magnetic fluxes of brushless machines is investigated. Given the time varying nature of the equations that describe the brushless machines electrical behaviour, the stability of time varying systems is studied adopting Lyapunov theory. Three observers are proposed for the estimation of the fluxes: the Luenberger Observer, the Kalman Filter and the Extended Kalman Filter. These algorithms are implemented in Simulink. The solutions found are tested and verified using a full Model in the Loop available at the LEMAD (Laboratory for Electric Machine and Drives) of the University of Bologna.
The observers are tested also with uncertainties in the resistance and inductances parameters, which is a common scenario in practice. A stability band for a diagonal observer gain, in discrete time, has been successfully found. In both the simulations with the known parameters and with variation of the statoric resistance, the estimated fluxes converge to the actual fluxes, but the RMS value of the error is better for the Extended Kalman Filter. For the simulations with the variations of the inductances, the estimation of the fluxes have worsened with more similar RMS error value among the three. In conclusion it was found that the Extended Kalman Filter has a better behaviour all around but it does not perform significantly better in the more realistic case. For this reason the proposed simpler Luenberger observer, designed using Lyapunov theory, can be a valid alternative.
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Colby, M. Amanda Earl Weaver Charles A. "Do actors or observers make better eyewitnesses?" Waco, Tex. : Baylor University, 2005. http://hdl.handle.net/2104/2683.
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Zhao, Yong 1980. "Discrete-time observers for inertial navigation systems." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/17956.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.Includes bibliographical references (p. 65-66).
In this thesis, we derive an exact deterministic nonlinear observer to compute the continuous-time states of inertial navigation system based on partial discrete measurements, the so-called strapdown problem. Nonlinear contraction theory is used as the main analysis tool. The hierarchical structure of the system physics is sytematically exploited and the use of nonlinear measurements, such as distances to time-varying reference points, is discussed. Effects of bounded errors on model and measurements are quantified, and can be used for active measurement selection. Work on vehicle state computation is carried out by using a similar observer design method. Finally, the approach is used to compute the head orientation of a simulated planar hopping robot, where the information provided by the observer is used for head stabilization and obstacle jump.
by Yong Zhao.
S.M.
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Jenkins, Benjamin Michael. "Fast adaptive observers for battery management systems." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111732.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2017.Cataloged from PDF version of thesis. Page 145 blank.
Includes bibliographical references (pages 139-144).
With the proliferation of batteries in transportation, mobile devices and, more recently, large scale energy storage, the demand for new efficient and safe algorithms for battery management has surged. More complex chemistry cells, such as lithium-ion batteries, with their sensitivity to mishandling, misuse and defects as is evident with recent device recalls due to fires, have historically been treated more conservatively. Maximizing performance of these cells safely requires knowledge of internal variables of interest which are not directly measurable. Therefore, accurate models which estimate these variables are needed. The focus of this thesis will be on a modified Single Particle Model (SPM), specifically its internal state estimates. Unfortunately, while the model structure is known, internal parameters which specify it are not, hence, state estimation alone is not enough. This motivates simultaneous state estimation and parameter identification of the electrochemical model. Existing solutions to this task are minimal in the literature. Hence this thesis. This thesis enumerates multiple developments in electrochemical modeling and adaptive observers in general. The first and fundamental component is a modification of the SPM with attractive features such as the encapsulation of lithium diffusion as a linear dynamical system independent of nonlinearities and decoupling of the nonlinear relationships defining the kinetic properties of lithium ion transfer and open circuit potential respectively. A second development defines a set of guidelines reducing the design parameters for adaptive observers to a single tuning parameter, enabling rapid implementation and prototyping. Third, a new variant of adaptive observer, using multiple simultaneous equivalent system representations, is derived for fast parameter convergence. A novel selection of observer design variables and augmentation of the underlying equivalent system with nonlinear basis functions constitutes a fourth development extensively validated through numerical simulation and theory. This adaptive observer combined with an independent offline algorithm to update effective electrode capacity and available lithium adapts every parameter of the modified SP model to account for aging or manufacturing differences. Validation of this observer in hardware using commercially available Panasonic 18650 cells completes the goals originally set forth for this research. The developments presented pave the way for fast, computationally efficient, advanced battery management systems with the potential to increase the effective capacity of a battery or alternatively reduce the size, and therefore cost, of batteries in various applications.
by Benjamin Michael Jenkins.
Ph. D.
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Lördal, Tigerström Gabriel. "Automated decision support for placing terrain observers." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264487.
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Access to reliable information is key for military decision-making. Reconnaissance assets are used to gather information about the Operational Environment. These assets need to be placed within the terrain so that they can see as much of the area of interest as possible. The manual task of placing assets within the terrain is a time-consuming task. This thesis examines the design for a system that could be used to generate candidate placement positions to aid the decision-maker. The system’s task is to find positions that maximize visual cover, while keeping the assets as safe as possible. The problem was formalized and reformulated into a multi-objective optimization problem. Three different optimization algorithms were evaluated: Simulated annealing, Tabu Search and the genetic algorithm NSGA-II. The optimization algorithms were tested in three different scenarios to reduce bias. The evaluation showed that NSGA-II had consistent gains over the other two algorithms.Militär beslutsfattning kräver pålitlig information rörande den operationella miljön. Ett sätt att inhämta information är genom rekognosering. För att rekognoseringsförband ska kunna utföra sitt arbete krävs det att de blir placerade så att de kan övervaka så stor del som möjligt av intresseområdet. Det manuella sättet att hitta och jämföra placeringspunkter är svårt och tidskrävande. Detta examensarbete utforskar utformningen av ett automatiserat system för att stötta beslutsfattaren. Systemet genererar förslag av lämpliga placeringspunkter som kan presenteras till beslutsfattaren. Dessa placeringspunkter är punkter som maximerar det som observatören ser, utan att försämra observatörens säkerhet. Problemet formaliserades och formulerades som ett optimeringsproblem med flera mål. Tre olika algoritmer implementerades och testades mot varandra. Algoritmerna testades i tre olika scenarion som skapades för att minska risken av partiska resultat.
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Kanakova, A. "Ordinary observers : London fiction of the 1930s." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1400117/.
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This thesis examines the London novel of the 1930s, with a focus on texts that made the ordinary, or typical, Londoner’s visual experience of the city their subject. While the main emphasis is on works by Patrick Hamilton, Jean Rhys, Storm Jameson, and George Orwell, several less-known and neglected London writers of the period are also considered. While the curiosity about the inner lives of ordinary city dwellers was not new in the 1930s, the rendering of Londoners’ interiorities through their visual perceptions became a prominent trend in the London novel during the decade. Importantly, visual experiences of the city in the novels under discussion are no longer the exclusive property of a sensitive, omniscient narrator. Rather, London is increasingly seen from the unexceptional, typically lower-middle-class observer’s point of view. The London novels discussed here were set in the city's spaces of leisure - cinemas, teashops, café bars, and the brightly lit streets of the West End. For the writers under discussion, these were much more than just settings. The spatial organisation of London’s public sphere between the Wars shaped not only the external appearance of the city, but also modes of being within it. In this thesis, then, the cultural history of 1930s London informs readings of the period’s writing. Readings of 1930s photographs form an integral part of the thesis. Literature and photography, insofar as the ordinary Londoner was concerned, occupied similar fields of enquiry. As the art form that was not only itself visual, but that frequently made others’ looking its subject, photography is closer to the 1930s London novel than any other mode of expression, and photographs both illustrate and illuminate the literary works under discussion.
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Ringstad, Randy. "Application of robust observers to time-series forecasting." abstract and full text PDF (UNR users only), 2009. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1472973.
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Ingallina, Alessandro. "Adaptive High-Gain Observers via Discete time Identifier." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
Find full textAbstract:
The system's state observation is one of the most important problem in control theory, and it becomes extremely challenging when the system model is not entirely known. For linear systems the problem is solved by using Luenberger observer in a deterministic framework and by Kalman filter in a stochastic framework, while for nonlinear systems, the observation problem is still a research topic. The aim of this thesis is to give a framework, in which the adaptation problem, relative to the model unknowns, can be performed by system identification techniques. In particular, in this thesis we develop and implement adaptive observers design, that uses "universal approximator" to perform the adaptation problem. Moreover, we present simulations on the performance of the proposed observer.
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Root, Philip J. "Persistent patrolling in the presence of adversarial observers." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/90728.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 205-217).
The majority of persistent patrolling strategies seek to minimize the time between visits or "idleness" of any target or location within an environment in an attempt to locate a hidden adversary as quickly as possible. Such strategies generally fail, however, to consider the game theoretic impacts of the adversary seeking to avoid the patroller's detection. The field of patrolling security games that addresses this two-player game is maturing with several authors posing the patrolling scenario as a leader-follower Stackelberg game where the adversary chooses to attack at a location and time as a best response to the patroller's policy. The state of the art grants the adversary complete global information regarding the patroller's location so as to choose the optimal time and location to attack, and this global information creates a considerable advantage for the adversary. We propose a significant improvement to this patrolling game state of the art by restricting the adversary access to only local information. We model the adversary as capable of collecting a sequence of local observations who must use this information to determine the optimal time to attack. This work proposes to find the optimal patrolling policy in different environments given this adversary model. We extensively study this patrolling game set on a perimeter with extensions to other environments. Teams of patrolling agents following this optimal policy achieve a higher capture probability, and we can determine the marginal improvement for each additional patroller. We pose several novel patrolling techniques inspired by a combination of discrete and continuous random walks, Markov processes, and random walks on Cayley graphs to ultimately model the game equilibrium when the team of patrollers execute so-called "presence patrols." Police and military forces commonly execute this type of patrolling to project their presence across an environment in an effort to deter crime or aggression, and we provide a rigorous analysis of the trade-off between increased patrolling speed and decreased probability of detection.
by Philip J. Root.
Ph. D.
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Astolfi, Daniele <1987>. "Observers and Robust Output Regulation for Nonlinear Systems." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7509/.
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The objective of this thesis is twofold: on one hand, the design of nonliner observers, on the other, the design of internal-model regulators to solve the robust output regulation problem.
In the observer theory a key role is played by the so called high-gain observers. The purpose of the first part of the thesis is to propose novel techniques which allow to overcome or at least to mitigate some of the main drawbacks characterizing this class of observers. Firstly, we study the possibility of writing an observer for multi-input multi-output observable systems in the original coordinates. Then, we propose a novel class of high-gain observers, denoted as ``low-power'', which allows to overcome numerical problems, to avoid the peaking phenomenon and to improve the sensitivity properties to high-frequency measurement noise.
The second part of the thesis addresses the output regulation problem, solved for linear systems during the 70's by Francis and Wonham who coined the celebrated ``internal model principle''. Constructive solutions have also been proposed in the nonlinear framework but under restrictive assumptions that reduce the class of systems to which this methodology can be applied. In this thesis we focus on the output regulation problem in presence of periodic disturbances and we propose a novel approach which allows to consider a broader class of nonlinear systems. With the proposed design the stabilization problem and the regulation problem are substantially decoupled and output regulation is achieved in presence of uncertainties or disturbances, as long as the trajectories of the resulting closed-loop system are bounded.
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Johansson, Andreas. "Nonlinear observers with applications in the steel industry." Doctoral thesis, Luleå tekniska universitet, Signaler och system, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18167.
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Access to measurements is a necessity in most technical applications, in order to detect faults, monitor performance, or exercise control. In some cases, however, installing measurement equipment is very expensive or even impossible. In such a case, estimates can be produced instead. In an observer, this is done by combining process knowledge, in the form of an analytical process model, with information, in the form of indirect measurements. If the process model is in the form of a system of linear differential equations, then the problem of constructing an observer is essentially solved by the Kalman filter and the Luenberger observer. For a system of nonlinear differential equations, however, there is no generic solution, which is the reason for extensive research in this area for the past decades. This thesis treats the development and analysis of nonlinear observers for three applications in the steel industry. The first application is the detection of gas leakages in a pulverized coal injection plant. An observer whose residual is sensitive to the gas leakage flow, has been designed for a nonlinear process model. A Generalized Likelihood Ratio test was applied to the residual to distinguish between different types of leakages. The method has been implemented in the plant and tested successfully with actual leakages. Furthermore, a Laguerre spectrum representation of the residual was utilized, to reduce disturbances and computational effort. The second application is the detection of clogging in pulverized coal injection lines. An observer, with a state variable that represents clogging, has been designed for a time-varying process model. An adaptive threshold for the estimated clogging variable was calculated. In experiments with data from the plant, the method was shown to detect clogging successfully, without producing false alarms. The third application is the estimation of metal analysis in the steel converter process. A nonlinear, physical process model was utilized and an observer was proposed, whose feedback is weighted by the sensitivity of the output with respect to the state. Experiments with data from a converter plant show that this strategy provides accurate estimates of the carbon content in the converter. Furthermore, a generalization of the proposed observer structure has been analyzed in terms of asymptotic stability and region of attraction.Godkänd; 2001; 20061113 (haneit)
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Tan, Chee Pin. "Sliding mode observers for fault detection and isolation." Thesis, University of Leicester, 2002. http://hdl.handle.net/2381/30204.
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This thesis describes the use of a class of sliding mode observers for fault detection and isolation purposes. Existing work has shown that the equivalent output error injection term associated with the sliding mode observer, which represents the average value of the nonlinear switched term (which induces and maintains the sliding motion), if properly scaled, yields accurate reconstructions of actuator faults. Existing observer design methods generate a certain class of observer gains, but do not utilise all degrees of freedom. In this thesis, a new method, exploiting this freedom is presented. The method uses Linear Matrix Inequalities and is easily implementable using standard software packages. New methods for accurately reconstructing sensor faults are also presented where appropriate filtering of certain measurable signals yields a fictitious system in which the original sensor faults are treated as actuator faults. Using the principles of actuator fault reconstruction in the existing work, sliding mode observers can be designed for the fictitious system to accurately reconstruct the sensor faults. This improves on the previous work where effectively only the steady state components of the sensor faults could be reconstructed. A new method using Linear Matrix Inequalities is presented, to synthesise observers which can robustly reconstruct faults in the presence of a class system of uncertainty, minimising the effect of the uncertainty on the fault reconstruction in an L2 sense. The robust fault reconstruction scheme is demonstrated by means of a case study, which is a nonlinear model of an aero-engine. System identification is used to obtain a linear model of the engine. An uncertainty representation is also obtained about which the observer is designed. The results from the case study show that the robust fault reconstruction scheme works and is effective.
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Mudford, Oliver Charles. "Assessment of the quality of observers' records of behaviour." Thesis, University of Auckland, 1990. http://hdl.handle.net/2292/1990.
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The measurement of behaviour by direct observation may be improved when observers have been provided with equipment which enables real-time recording. There are no data available concerning the quality of this type of measurement. Indeed, there is no consensus among researchers as to appropriate methods of quality assessment. In the present series of studies, observers were provided with hand-held computers programmed to act as real-time recorders. The quality of their records was assessed by three "traditional" methods, representative of those which have been used most frequently in previous behavioural research: interobserver agreement, observer/criterion agreement, and relative error. An instrument calibration procedure, the standard method for measurement accuracy analysis in the natural sciences and engineering, was demonstrated for comparison with traditional methods. The traditional methods were found to be unsatisfactory for theoretical and empirical reasons. The calibration procedure was shown to have some considerable potential advantages for applied behaviour analysis. Disadvantages, both statistical and practical, were also discussed.
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Exposito, Garcia Adrian. "Investigation on Model Based Observers for SpaceStructure Load Characterization." Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-60732.
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The experimental determination of dynamic characteristics of elastic structures, in particularof space flight related structures typically is performed by experimental modal analysis(EMA) or output-only modal analysis (OMA). This document is focused on the OMA methodsand state-space modelling, the motivation for this approach is the possibility to monitorthe real loading of a structure in order to provide a loading history which may be used foran assessment of safe remaining life once the dynamic characteristics has been determined. Previous work has demonstrated that Extened Kalman Filter is not sufficient in thecase when the forces are unkown and the only resource available are the responses of thestructure. In this research a new method called Unscented Kalman Filter is investigated andimplemented, proving its capability to obtain a better approximation of the elastic structurebehaviour and a correction of the modal parameters.
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Yamalova, Diana. "Hybrid observers for systems with intrinsic pulse-modulated feedback." Licentiate thesis, Uppsala universitet, Avdelningen för systemteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-316058.
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This licentiate thesis deals with a special class of hybrid systems, where the continuous linear part is controlled by an intrinsic impulsive feedback that contributes discrete dynamics. The impacting pulsatile feedback signal is not available for measurement and, therefore, has to be reconstructed. To estimate all the elements of the hybrid state vector, an observation problem is considered. The motivation for the research performed in this thesis comes from mathematical modelling of pulsatile endocrine regulation, where one of the hormones (a releasing hormone) is secreted in pulses from neurons in the hypothalamus of the brain. Thus a direct measurement of the concentration of this hormone in the human is not possible for ethical reasons and has to be estimated. Several hybrid observer structures are proposed and evaluated. The observer design is reduced to a problem of synchronizing the impulsive sequence produced by the observer with that of the plant. It utilizes a local approach of assigning, through the output error feedback in both the discrete and continuous parts of the plant model, a guaranteed convergence rate to the local dynamics of a synchronous mode. Performance of the proposed observer schemes is analyzed by means of pointwise discrete (Poincaré) maps. The first two papers of the thesis address the effects of observer design degrees of freedom on the convergence of the hybrid state estimation error. A generalization of the proposed observation scheme to hybrid impulsive systems with a time delay in continuous part of the plant is investigated in Paper III and Paper IV.
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Nezvalová, Kristýna. "Monitoring pohybů skalních bloků." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226214.
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The thesis deals with monitoring of rock blocks movements near sinking stream Bílá voda situated near the village Holštejn in Moravian Karst. The thesis follows up results, which were gained in years 2004-2011. The aim of thesis is survey of the 16th stage in summer 2012 and 17th stage in autumn 2012, following processing of surveying data and evaluation of space movements. Achieved results are compared mutually and they are analysed towards results of previous periods. The final results are documented numerically and graphicallyl.
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Smolinka, Martin. "Stanovení pohybů skalních bloků." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-390204.
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The subject of the diploma thesis is monitoring of rocks blocks movements near sinking stream Bílá voda situated near the village Holštejn in Moravian Karst. The aim of thesis is to measure of the 21th stage and 22th stage in year 2017. The thesis follows on the results obtained in years 2004-2015. Achieved results are mutually compared and analysed towards the results of previous stages. The final results are shown numerically and graphically
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Sebsadji, Yazid. "Numérisation et reconstruction 3D de la géométrie de la route par observateurs et stéréovision embarquée." Thesis, Evry-Val d'Essonne, 2009. http://www.theses.fr/2009EVRY0025/document.
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La connaissance du profil et des attributs de la route est un élément critique dans le développement des assistances à la conduite. Ceci est notamment le cas pour les applications d’alerte et d’aide au maintien de voie. Les résultats des travaux de perception, vidéo notamment, permettent uniquement une localisation relative du véhicule par rapport à la route. Ce type de localisation ne permet pas l’accès au positionnement absolu de la route. A ce titre, il est impossible d’avoir accès au devers de la route via une seule caméra vidéo montée en vision frontale. Pour surmonter cette difficulté, nous proposons dans cette thèse une approche de numérisation et de reconstruction 3D de la géométrie de la route (pente, devers et courbure) dans un repère absolu supposé galiléen. L’idée générale de la numérisation 3D de la route, consiste à localiser le véhicule en 3D, faire le recalage pour obtenir celui du centre de la voie et d’associer à chaque positionnement les valeurs numériques des différents attributs de la route. L’approche développée consiste en la fusion d’informations provenant d’une part de capteurs proprioceptifs et extéroceptifs et d’autre part d’observateurs. On y distingue trois phases principales : La première a pour objet l’estimation des attributs de la route à l’aide d’observateurs. La deuxième est dédiée au positionnement relatif de la route par rapport au véhicule à partir de capteurs de vision embarqués sur le véhicule. La dernière phase aboutit à la reconstruction 3D de la route par fusion des informations provenant des deux premières phases. Techniquement les états des véhicules et les attributs de la route sont reconstruit à l’aide de filtres de Kalman étendus et d’observateurs à entrées inconnues. Par la suite, la géométrie 3D de la route, dans le repère absolu, est obtenue en calculant la matrice de passage du repère relatif, lié aux capteurs embarqués, au repère absolu. On utilise pour cela un schéma de fusion avec les données issues du capteur vidéo et les données GPS en utilisant les techniques IMM (Interacting Multiple Models)The knowledge of the profile and the road attributes is a critical item in the development of driving assistances. This is specially the case for alert applications and lateral control. The results of the perception studies, specially the video, only allow a relative localization of the vehicle on the road. This kind of localization does not allow the access to absolute positioning of the road. For this reason, it is impossible to have access to the road bank via only one video camera fixed in frontal view. To overcome this difficulty, we propose in this thesis an approach of digitalization and 3Dreconstruction of the geometry of the road (slope, road bank and curvature) in an absolute frame, supposed Galilean. The general idea of 3D-digitalization of the road consist in localizing the vehicle in 3D, doing the correction to obtain the one of the road center and to associate, to each positioning, the numerical values of the different attributes of the road. The developed approach consists in the fusion of information coming from proprioceptive and exteroceptive sensors on one hand and observers on the other. We find in it three principal cases: The first one has for object the estimation of the road attributes via observers. The second one is dedicated to the relative positioning of the road beside the vehicle via embedded video sensors in the vehicle. The last stage leads to the 3D-reconstruction of the road via fusion of information coming from the two first stages. Technically, the states of the vehicles and the road attributes are reconstructed by application of the extended Kalman filters and proportional integral observers with unknown inputs. Afterwards, the 3D-geometry of the road, in the absolute landmark, is obtained by calculating the transfer matrix from the relative frame, linked to embedded sensors, to the absolute frame. For that, we use a fusion scheme with the video sensors and GPS data by using the IMM techniques
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Wilkerson, James Michael. "An attribution-centered model of observers' reactions to workplace aggression." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/29988.
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Meseguer, Amela Jordi. "Integration Techniques of Fault Detection and Isolation Using Interval Observers." Doctoral thesis, Universitat Politècnica de Catalunya, 2009. http://hdl.handle.net/10803/52812.
Full textAbstract:
An interval observer has been illustrated to be a suitable approach to detect and isolate faults affecting complex dynamical industrial systems.
Concerning fault detection, interval observation is an appropriate passive robust strategy to generate an adaptive threshold to be used in residual
evaluation when model uncertainty is located in parameters (interval model). In such approach, the observer gain is a key parameter since it determines
the time evolution of the residual sensitivity to a fault and the minimum detectable fault. This thesis illustrates that the whole fault detection process is
ruled by the dynamics of the fault residual sensitivity functions and by the time evolution of the adaptive threshold related to the interval observer.
Besides, it must be taken into account that these two observer fault detection properties depend on the used observer gain. As a consequence, the
observer gain becomes a tuning parameter which allows enhancing the observer fault detection performance while avoiding some drawbacks related to
the analytical models, as the wrapping effect. In this thesis, the effect of the observer gain on fault detection and how this parameter can avoid some
observer drawbacks (i.e. wrapping effect) are deeply analyzed. One of the results of this analysis is the determination of the minimum detectable fault
function related to a given fault type. This function allows introducing a fault classification according to the fault detectability time evolution:
permanently (strongly) detected, non-permanently (weakly) detected or just non-detected. In this fault detection part of this thesis, two examples
have been used to illustrate the derived results: a mineral grinding-classification process and an industrial servo actuator.
Concerning the interface between fault detection and fault isolation, this thesis shows that both modules can not be considered separately since the
fault detection process has an important influence on the fault isolation result. This influence is not only due to the time evolution of the fault signals
generated by the fault detection module but also to the fact that the fault residual sensitivity functions determines the faults which are affecting a given
fault signal and the dynamics of this fault signal for each fault. This thesis illustrates this point suggesting that the interface between fault detection and
fault isolation must consider a set of fault signals properties: binary property, sign property, fault residual sensitivity property, occurrence order property
and occurrence time instant property. Moreover, as a result of the influence of the observer gain on the fault detection stage and on the fault residual
sensitivity functions, this thesis demonstrates that the observer gain has also a key role in the fault isolation module which might allow enhancing its
performance when this parameter is tuned properly (i.e. fault distinguishability may be increased). As a last point, this thesis analyzes the timed
discrete-event nature of the fault signals generated by the fault detection module. As a consequence, it suggests using timed discrete-event models to
model the fault isolation module. This thesis illustrates that this kind of models allow enhancing the fault isolation result. Moreover, as the monitored
system is modelled using an interval observer, this thesis shows as this qualitative fault isolation model can be built up on the grounds of this system
analytical model. Finally, the proposed fault isolation method is applied to detect and isolate faults of the Barcelona’s urban sewer system limnimeters.
Keywords: Fault Detection, Fault Diagnosis, Robustness, Observers, Intervals, Discrete-event Systems.En la presente tesis se demuestra que el uso de observadores intervalares para detectar y aislar fallos en sistemas dinámicos complejos constituye una estrategia apropiada. En la etapa de detección del fallo, dicha estrategia permite determinar el umbral adaptativo usado en la evaluación del residuo (robustez pasiva). Dicha metodología, responde a la consideración de modelos con parámetros inciertos (modelos intervalares). En dicho enfoque, la ganancia del observador es un parámetro clave que permite determinar la evolución temporal de la sensibilidad del residuo a un fallo y el mínimo fallo detectable para un tipo de fallo determinado. Esta tesis establece que todo el proceso de detección de fallos viene determinado por la dinámica de las funciones sensibilidad del residuo a los diferentes fallos considerados y por la evolución temporal del umbral adaptativo asociado al observador intervalar. Además, se debe tener en cuenta que estas dos propiedades del observador respecto la detección de fallos dependen de la ganancia del observador. En consecuencia, la ganancia del observador se convierte en el parámetro de diseño que permite mejorar las prestaciones de dicho modelo respecto la detección de fallos mientras que permite evitar algunos defectos asociados al uso de modelos intervalares, como el efecto wrapping. Uno de los resultados obtenidos es la determinación de la función fallo mínimo detectable para un tipo de fallo dado. Esta función permite introducir una clasificación de los fallos en función de la evolución temporal de su detectabilidad: fallos permanentemente detectados, fallos no permanentemente detectados y fallos no detectados. En la primera parte de la tesis centrada en la detección de fallos se utilizan dos ejemplos para ilustrar los resultados obtenidos: un proceso de trituración y separación de minerales y un servoactuador industrial. Respecto a la interfaz entre la etapa de detección de fallos y el proceso de aislamiento, esta tesis muestra que ambos módulos no pueden considerarse separadamente dado que el proceso de detección tiene una importante influencia en el resultado de la etapa de aislamiento. Esta influencia no es debida sólo a la evolución temporal de las señales de fallo generados por el módulo de detección sino también porque las funciones sensibilidad del residuo a los diferentes posibles fallos determinan los fallos que afectan a un determinado señal de fallo y la dinámica de éste para cada uno de los fallos. Esta tesis ilustra este punto sugiriendo que el interfaz entre detección y aislamiento del fallo debe considerar un conjunto de propiedades de dichos señales: propiedad binaria, propiedad del signo, propiedad de la sensibilidad del residuo a un fallo dado, propiedad del orden de aparición de las señales causados por los fallos y la propiedad del tiempo de aparición de estos. Además, como resultado de la influencia de la ganancia del observador en la etapa de detección y en las funciones sensibilidad asociadas a los residuos, esta tesis ilustra que la ganancia del observador tiene también un papel crucial en el módulo de aislamiento, el cual podría permitir mejorar el comportamiento de dicho módulo diseñando éste parámetro del observador de forma adecuada (Ej. Incrementar la distinción de los fallos para su mejor aislamiento). Como último punto, esta tesis analiza la naturaleza temporal de eventos discretos asociada a las señales de fallo generados por el módulo de detección. A consecuencia, se sugiere usar modelos de eventos discretos temporales para modelizar el módulo de aislamiento del fallo. Esta tesis muestra que este tipo de modelos permite mejorar el resultado de aislamiento del fallo. Además, dado que el sistema monitorizado es modelado usando un observador intervalar, esta tesis muestra como este modelo cualitativo de aislamiento puede ser construido usando dicho modelo analítico del sistema. Finalmente, el método propuesto de aislamiento del fallo es aplicado para detectar y aislar fallos en los limnimetros del sistema de alcantarillado de Barcelona. Palabras clave: Detección de Fallos, Diagnosis de Fallos, Robusteza, Observadores, Intervalos, Sistemas de Eventos Discretos.
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Björkman, Mårten. "Real-Time Motion and Stereo Cues for Active Visual Observers." Doctoral thesis, KTH, Numerical Analysis and Computer Science, NADA, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3382.
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Opsanger, Eirik Nyland. "A Comparison of Observers for Estimation of the Bottomhole Pressure." Thesis, Norwegian University of Science and Technology, Department of Engineering Cybernetics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-8970.
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New offshore oil recourses that are developed are more difficult to drill and increase the requirements to the technology in the offshore industry. A relatively new technology is Managed Pressure Drilling where a choke topside is used to control the bottom hole pressure. The bottom hole pressure measurement is unreliable, which motivates the need for an observer. Different methods for estimation will be presented and compared in this thesis. Proofs of convergence are outlined for the Stamnes observer, derived for the Grip observer and some stepping stones for further work are presented for the Optimal Polynomial Filter. Each observer is simulated with a simple step in the mud pump to verify the estimation laws. The results show that all observes estimated the bottom hole pressure correctly for this simple case. A more realistic case, a pipe connection, is also simulated for each observer. The case includes zero flow from the mud pump, which reveals that all observers miss the estimation convergence in this case, but that the estimate converges when there is flow from the mud pump. One of the states that affects the bottom hole pressure is the pressure loss due to friction in drill string and annulus. Earlier work modeled these losses as quadratic with respect to the flow through the bit, which are simplifications. To improve the estimate of the bottom hole pressure, new and better friction models are needed. Measurement data from Gullfaks C are analyzed to get new knowledge of friction loss in the drilling string and annulus. For the drill string the quadratic friction model is found to be good enough, catching the main behavior. On the other hand, the friction loss in the annulus is a more complicated function of flow. The annulus friction is approximated with sets of basis functions and the weighted sum of these functions gives an approximation to the friction curve. Each weight is estimated to get the friction loss estimate. The use of the weighted sum of four 1st-order b-spline functions give a good approximation to the real friction curve, and the weight for each basis function is estimated. This is tested in simulations both with a simple case and the pipe connection case. The simulations show that the annulus friction loss and the bit pressure are estimated correctly.
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Speranza, Filippo. "Binocular detection of masked signals in young and old observers." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq41044.pdf.
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Yao, Jie. "Model observers for predicting human performance on signal detection tasks." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186612.
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Various model observers have been applied to the objective assessment of medical image quality. However, the relevance of this application to clinical efficacy depends largely on how well model observers predict human performance. Attempting to answer this question, this dissertation focuses on the investigation of a linear observer known as the Hotelling observer and a modified version of the Hotelling observer, known as the channelized Hotelling observer. Performances of these observers for a signal-known-exactly detection task are calculated and compared to the performance of the human observer. Several psychophysical studies suggest that the Hotelling observer, formulated on the first- and second-order statistical properties of the images, could predict the human performance very well. To investigate the effect of certain higher-order statistical information on human performance, an experiment was designed in which the mean, variance, and covariance of three groups of images were kept the same, while the shapes of the image grey-level histogram were varied. The results showed little practical difference in the human performance among the three groups; thus the higher-order statistical information represented by the shape of the grey-level histogram did not influence the human observer's signal-detection performance for the task considered in this experiment. Another linear model observer, the nonprewhitening observer has been found in previous work to predict human performance better than the Hotelling observer for images with uniform backgrounds and correlated noise. When the images contain nonuniform background and uncorrelated noise, however, the Hotelling observer is found to be better in predicting human performance. To unify these results, a channelized Hotelling observer was proposed whose performance resembles that of a nonprewhitening observer for images with correlated noise, and that of a Hotelling observer for images with nonuniform background. Moreover, the channelized Hotelling observer is able to predict human performance when images have both the nonuniform background and correlated noise. A nonlinear version of the channelized Hotelling observer has also been found to predict human performance well.
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Anderson, Mary-Jane Charlotte. "Nonintentional behavioural responses to psi : hidden targets and hidden observers." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/7992.
Full textAbstract:
Psi is the phenomenon of apparently responding to or receiving information by means other than the recognised senses. Psi information may influence human behaviour, without the individual intending this or even being aware of it. This thesis seeks to investigate nonintentional behavioural responses to psi. We present five empirical studies that investigated nonintentional behavioural responses to psi information. In each study, the psi information was hidden from participants, in that the participants neither had sensory access to it, nor did they know that it existed. Two different combinations of psi information and a behavioural response were examined. The first was the influence of hidden psi information on psychological task performance. The second was the influence of covert, remote observation by hidden observers on the social facilitation effect. In all the studies, the effects of individual differences in participants’ personalities were also considered. In Experiment 1 we investigated whether hidden targets influenced participants’ judgements of the lengths of lines. There was no overall psi effect, but we found a replication of a response bias effect and a significant correlation between psi and participants’ extraversion. In Experiment 2 we investigated whether hidden targets influenced participants’ speed on a maths task. There was no overall psi effect and no correlations between personality and psi scores. We reviewed previous research literature on social facilitation from the novel angle of investigating whether being watched can, in and of itself, lead to the social facilitation effect. Experiments 3, 4, and 5 developed the paradigm of testing for a social facilitation effect from remote observation, investigating whether remote observation leads to the same behavioural changes as knowingly being observed by a physically present person. We compared participants’ performance on psychological tasks under different observation conditions: alone, remotely observed by a hidden observer, and observed by a physically present observer. The expected social facilitation effect was not found in these experiments, leading to a series of improvements to the sampling, methodology, and tasks over the course of these experiments. As the social facilitation effect from a physically present observer was not reliably replicated, these experiments were not conclusive tests of whether there is a social facilitation effect from remote observation. However, there was an indication in Experiment 3 that remote observation does not exert a significant behavioural effect. Considered together, our studies explored novel approaches to examining nonintentional behavioural responses to psi. The significant correlation between participants’ extraversion and psi is, to our knowledge, the first time this effect has been found in a nonintentional psi experiment. This, and the replication of the response bias effect, represent important advances in parapsychology. Our experiments are also the first to test the assumption, inherent in many research designs, that covert observation does not affect participants’ behaviour. Overall, our findings did not support the psi hypothesis.
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Heydari, Mahdi. "Adaptive distributed observers for a class of linear dynamical systems." Digital WPI, 2015. https://digitalcommons.wpi.edu/etd-dissertations/227.
Full textAbstract:
The problem of distributed state estimation over a sensor network in which a set of nodes collaboratively estimates the state of continuous-time linear systems is considered. Distributed estimation strategies improve estimation and robustness of the sensors to environmental obstacles and sensor failures in a sensor network. In particular, this dissertation focuses on the benefits of weight adaptation of the interconnection gains in distributed Kalman filters, distributed unknown input observers, and distributed functional observers. To this end, an adaptation strategy is proposed with the adaptive laws derived via a Lyapunov-redesign approach. The justification for the gain adaptation stems from a desire to adapt the pairwise difference of estimates as a function of their agreement, thereby enforcing an interconnection-dependent gain. In the proposed scheme, an adaptive gain for each pairwise difference of the interconnection terms is used in order to address edge-dependent differences in the estimates. Accounting for node-specific differences, a special case of the scheme is presented where it uses a single adaptive gain in each node estimate and which uniformly penalizes all pairwise differences of estimates in the interconnection term. In the case of distributed Kalman filters, the filter gains can be designed either by standard Kalman or Luenberger observers to construct the adaptive distributed Kalman filter or adaptive distributed Luenberger observer. Stability of the schemes has been shown and it is independent of the graph topology and therefore the schemes are applicable to both directed and undirected graphs. The proposed algorithms offer a significant reduction in communication costs associated with information flow by the nodes compared to other distributed Kalman filters. Finally, numerical studies are presented to illustrate the performance and effectiveness of the proposed adaptive distributed Kalman filters, adaptive distributed unknown input observers, and adaptive distributed functional observers.
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Sonthikorn, Paisarn 1977. "Design of observers for the swing dynamics of power networks." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/87837.
Full textAbstract:
Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002.Includes bibliographical references (leaf 53).
by Paisarn Sonthikorn.
M.Eng.
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Nagesh, Indira. "Fault diagnosis for a satellite system using sliding mode observers." Thesis, University of Leicester, 2014. http://hdl.handle.net/2381/31619.
Full textAbstract:
This thesis presents the theoretical development along with verification and validation campaign for fault detection and isolation (FDI) schemes applied to a satellite system. Specifically FDI schemes developed in the thesis are applied to the problems of actuator and sensor fault detection based on the nonlinear model of Mars Express Satellite (MEX). Model based FDI schemes are not implemented in the current health monitor schemes on board the MEX satellite, which is an over actuated system with the actuators and sensors having a specific tetrahedral configuration. A simple nonlinear sliding mode observers based on unit vector and super twisting methods developed in the thesis are verified on both rigid body and flexible mode models of the nonlinear MEX satellite. Faults for thrusters are applied during initial strong controller mode phase and also later stages of sun acquisition mode (SAM). Both dedicated observers and a bank of observers are designed to generate residuals which are used to detect and isolate faults. Unlike the reduced order systems typically obtained when using sliding modes in literature, this particular application produces no reduced order dynamics. All the schemes utilize the equivalent injection signal found in the sliding mode literature, which are then filtered using a simple integrator to generate threshold based residual analysis to detect faults or isolate faulty components. Verification and validation campaign consists initially with specific fault simulation and later with Monte Carlo simulations with uncertainties and noise are used to verify the performance of the designed schemes. A new multi-variable version of the super twisting algorithm is proposed along with a Lyapunov approach to analyze its stability. Existing super twisting schemes assumes a single control input structure. The proposed scheme demonstrates that it can be applicable to vector cases, where the decoupling of the control input between states is not possible. Finally a comparison between first order sliding mode observers based on unit vector methods and a second order super twisting observer is made using Monte Carlo simulations in the presence of noise and uncertainty for both the rigid body and flexible mode models of the satellite. The analysis establishes that both methods show good performance and robustness for fault diagnosis, which can be applied for all controller mode changes during several phases of SAM.
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Cignali, Giovanni <1981>. "Nonlinear Observers for Sensorless Control of Permanent Magnet Synchronous Motors." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5585/.
Full textAbstract:
In this thesis, the industrial application of control a Permanent Magnet Synchronous Motor in a sensorless configuration has been faced, and in particular the task of estimating the unknown “parameters” necessary for the application of standard motor control algorithms. In literature several techniques have been proposed to cope with this task, among them the technique based on model-based nonlinear observer has been followed.
The hypothesis of neglecting the mechanical dynamics from the motor model
has been applied due to practical and physical considerations, therefore only the electromagnetic dynamics has been used for the observers design.
First observer proposed is based on stator currents and Stator Flux dynamics described in a generic rotating reference frame. Stator flux dynamics are known apart their initial conditions which are estimated, with speed that is also unknown, through the use of the Adaptive Theory.
The second observer proposed is based on stator currents and Rotor Flux dynamics described in a self-aligning reference frame.
Rotor flux dynamics are described in the stationary reference frame exploiting polar coordinates instead of classical Cartesian coordinates, by means the estimation of amplitude and speed of the rotor flux. The stability proof is derived in a Singular Perturbation Framework, which allows
for the use the current estimation errors as a measure of rotor flux estimation errors. The stability properties has been derived using a specific theory for systems with time scale separation, which guarantees a semi-global practical stability.
For the two observer ideal simulations and real simulations have been performed to prove the effectiveness of the observers proposed, real simulations on which the effects of the Inverter nonlinearities have been introduced, showing the already known problems of the model-based observers for low speed applications.