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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Statistical Analysis of Geolocation Fundamentals Using Stochastic Geometry

O'Lone, Christopher Edward 22 January 2021 (has links)
The past two decades have seen a surge in the number of applications requiring precise positioning data. Modern cellular networks offer many services based on the user's location, such as emergency services (e.g., E911), and emerging wireless sensor networks are being used in applications spanning environmental monitoring, precision agriculture, warehouse and manufacturing logistics, and traffic monitoring, just to name a few. In these sensor networks in particular, obtaining precise positioning data of the sensors gives vital context to the measurements being reported. While the Global Positioning System (GPS) has traditionally been used to obtain this positioning data, the deployment locations of these cellular and sensor networks in GPS-constrained environments (e.g., cities, indoors, etc.), along with the need for reliable positioning, requires a localization scheme that does not rely solely on GPS. This has lead to localization being performed entirely by the network infrastructure itself, or by the network infrastructure aided, in part, by GPS. In the literature, benchmarking localization performance in these networks has traditionally been done in a deterministic manner. That is, for a fixed setup of anchors (nodes with known location) and a target (a node with unknown location) a commonly used benchmark for localization error, such as the Cramer-Rao lower bound (CRLB), can be calculated for a given localization strategy, e.g., time-of-arrival (TOA), angle-of-arrival (AOA), etc. While this CRLB calculation provides excellent insight into expected localization performance, its traditional treatment as a deterministic value for a specific setup is limited. Rather than trying to gain insight into a specific setup, network designers are more often interested in aggregate localization error statistics within the network as a whole. Questions such as: "What percentage of the time is localization error less than x meters in the network?" are commonplace. In order to answer these types of questions, network designers often turn to simulations; however, these come with many drawbacks, such as lengthy execution times and the inability to provide fundamental insights due to their inherent ``block box'' nature. Thus, this dissertation presents the first analytical solution with which to answer these questions. By leveraging tools from stochastic geometry, anchor positions and potential target positions can be modeled by Poisson point processes (PPPs). This allows for the CRLB of position error to be characterized over all setups of anchor positions and potential target positions realizable within the network. This leads to a distribution of the CRLB, which can completely characterize localization error experienced by a target within the network, and can consequently be used to answer questions regarding network-wide localization performance. The particular CRLB distribution derived in this dissertation is for fourth-generation (4G) and fifth-generation (5G) sub-6GHz networks employing a TOA localization strategy. Recognizing the tremendous potential that stochastic geometry has in gaining new insight into localization, this dissertation continues by further exploring the union of these two fields. First, the concept of localizability, which is the probability that a mobile is able to obtain an unambiguous position estimate, is explored in a 5G, millimeter wave (mm-wave) framework. In this framework, unambiguous single-anchor localization is possible with either a line-of-sight (LOS) path between the anchor and mobile or, if blocked, then via at least two NLOS paths. Thus, for a single anchor-mobile pair in a 5G, mm-wave network, this dissertation derives the mobile's localizability over all environmental realizations this anchor-mobile pair is likely to experience in the network. This is done by: (1) utilizing the Boolean model from stochastic geometry, which statistically characterizes the random positions, sizes, and orientations of reflectors (e.g., buildings) in the environment, (2) considering the availability of first-order (i.e., single-bounce) reflections as well as the LOS path, and (3) considering the possibility that reflectors can either facilitate or block reflections. In addition to the derivation of the mobile's localizability, this analysis also reveals that unambiguous localization, via reflected NLOS signals exclusively, is a relatively small contributor to the mobile's overall localizability. Lastly, using this first-order reflection framework developed under the Boolean model, this dissertation then statistically characterizes the NLOS bias present on range measurements. This NLOS bias is a common phenomenon that arises when trying to measure the distance between two nodes via the time delay of a transmitted signal. If the LOS path is blocked, then the extra distance that the signal must travel to the receiver, in excess of the LOS path, is termed the NLOS bias. Due to the random nature of the propagation environment, the NLOS bias is a random variable, and as such, its distribution is sought. As before, assuming NLOS propagation is due to first-order reflections, and that reflectors can either facilitate or block reflections, the distribution of the path length (i.e., absolute time delay) of the first-arriving multipath component (MPC) is derived. This result is then used to obtain the first NLOS bias distribution in the localization literature that is based on the absolute delay of the first-arriving MPC for outdoor time-of-flight (TOF) range measurements. This distribution is shown to match exceptionally well with commonly assumed gamma and exponential NLOS bias models in the literature, which were only attained previously through heuristic or indirect methods. Finally, the flexibility of this analytical framework is utilized by further deriving the angle-of-arrival (AOA) distribution of the first-arriving MPC at the mobile. This distribution gives novel insight into how environmental obstacles affect the AOA and also represents the first AOA distribution, of any kind, derived under the Boolean model. In summary, this dissertation uses the analytical tools offered by stochastic geometry to gain new insights into localization metrics by performing analyses over the entire ensemble of infrastructure or environmental realizations that a target is likely to experience in a network. / Doctor of Philosophy / The past two decades have seen a surge in the number of applications requiring precise positioning data. Modern cellular networks offer many services based on the user's location, such as emergency services (e.g., E911), and emerging wireless sensor networks are being used in applications spanning environmental monitoring, precision agriculture, warehouse and manufacturing logistics, and traffic monitoring, just to name a few. In these sensor networks in particular, obtaining precise positioning data of the sensors gives vital context to the measurements being reported. While the Global Positioning System (GPS) has traditionally been used to obtain this positioning data, the deployment locations of these cellular and sensor networks in GPS-constrained environments (e.g., cities, indoors, etc.), along with the need for reliable positioning, requires a localization scheme that does not rely solely on GPS. This has lead to localization being performed entirely by the network infrastructure itself, or by the network infrastructure aided, in part, by GPS. When speaking in terms of localization, the network infrastructure consists of what are called anchors, which are simply nodes (points) with a known location. These can be base stations, WiFi access points, or designated sensor nodes, depending on the network. In trying to determine the position of a target (i.e., a user, or a mobile), various measurements can be made between this target and the anchor nodes in close proximity. These measurements are typically distance (range) measurements or angle (bearing) measurements. Localization algorithms then process these measurements to obtain an estimate of the target position. The performance of a given localization algorithm (i.e., estimator) is typically evaluated by examining the distance, in meters, between the position estimates it produces vs. the actual (true) target position. This is called the positioning error of the estimator. There are various benchmarks that bound the best (lowest) error that these algorithms can hope to achieve; however, these benchmarks depend on the particular setup of anchors and the target. The benchmark of localization error considered in this dissertation is the Cramer-Rao lower bound (CRLB). To determine how this benchmark of localization error behaves over the entire network, all of the various setups of anchors and the target that would arise in the network must be considered. Thus, this dissertation uses a field of statistics called stochastic geometry} to model all of these random placements of anchors and the target, which represent all the setups that can be experienced in the network. Under this model, the probability distribution of this localization error benchmark across the entirety of the network is then derived. This distribution allows network designers to examine localization performance in the network as a whole, rather than just for a specific setup, and allows one to obtain answers to questions such as: "What percentage of the time is localization error less than x meters in the network?" Next, this dissertation examines a concept called localizability, which is the probability that a target can obtain a unique position estimate. Oftentimes localization algorithms can produce position estimates that congregate around different potential target positions, and thus, it is important to know when algorithms will produce estimates that congregate around a unique (single) potential target position; hence the importance of localizability. In fifth generation (5G), millimeter wave (mm-wave) networks, only one anchor is needed to produce a unique target position estimate if the line-of-sight (LOS) path between the anchor and the target is unimpeded. If the LOS path is impeded, then a unique target position can still be obtained if two or more non-line-of-sight (NLOS) paths are available. Thus, over all possible environmental realizations likely to be experienced in the network by this single anchor-mobile pair, this dissertation derives the mobile's localizability, or in this case, the probability the LOS path or at least two NLOS paths are available. This is done by utilizing another analytical tool from stochastic geometry known as the Boolean model, which statistically characterizes the random positions, sizes, and orientations of reflectors (e.g., buildings) in the environment. Under this model, considering the availability of first-order (i.e., single-bounce) reflections as well as the LOS path, and considering the possibility that reflectors can either facilitate or block reflections, the mobile's localizability is derived. This result reveals the roles that the LOS path and the NLOS paths play in obtaining a unique position estimate of the target. Using this first-order reflection framework developed under the Boolean model, this dissertation then statistically characterizes the NLOS bias present on range measurements. This NLOS bias is a common phenomenon that arises when trying to measure the distance between two nodes via the time-of-flight (TOF) of a transmitted signal. If the LOS path is blocked, then the extra distance that the signal must travel to the receiver, in excess of the LOS path, is termed the NLOS bias. As before, assuming NLOS propagation is due to first-order reflections and that reflectors can either facilitate or block reflections, the distribution of the path length (i.e., absolute time delay) of the first-arriving multipath component (MPC) (or first-arriving ``reflection path'') is derived. This result is then used to obtain the first NLOS bias distribution in the localization literature that is based on the absolute delay of the first-arriving MPC for outdoor TOF range measurements. This distribution is shown to match exceptionally well with commonly assumed NLOS bias distributions in the literature, which were only attained previously through heuristic or indirect methods. Finally, the flexibility of this analytical framework is utilized by further deriving angle-of-arrival (AOA) distribution of the first-arriving MPC at the mobile. This distribution yields the probability that, for a specific angle, the first-arriving reflection path arrives at the mobile at this angle. This distribution gives novel insight into how environmental obstacles affect the AOA and also represents the first AOA distribution, of any kind, derived under the Boolean model. In summary, this dissertation uses the analytical tools offered by stochastic geometry to gain new insights into localization metrics by performing analyses over all of the possible infrastructure or environmental realizations that a target is likely to experience in a network.
242

An Experiment to Show the Efficiency with Which Children of the Intermediate Grades of the Public Schools Use Their Sight-Reading Vocabularies in Their Written Self-Expression

Grant, Bessie May 08 1900 (has links)
The purposes of the study are to find ways of improving children's written self-expression and to consider the economy of a more effective use of the transitional stage of learning when words recognized are becoming words used in self-expression.
243

Исследование жизнестойкости лиц с нарушениями зрения : магистерская диссертация / The resilience research of people with sight disabilities

Решетникова, А. В., Reshetnikova, A. V. January 2018 (has links)
Объектом исследования явилась жизнестойкость лиц с нарушениями зрения. Предметом исследования стали предикторы жизнестойкости лиц с нарушениями зрения. Магистерская диссертация состоит из введения, трех глав, заключения, списка литературы (134 источника) и 6 приложений, включающих в себя описание применявшихся методик и компонентов жизнестойкости, информационное письмо для родителей испытуемых, бланк для выбора шрифта, комфортного для чтения, таблицы с основными качественными и статистическими результатами исследования. Объем магистерской диссертации составляет 124 страницы, на которых размещены 15 рисунков-диаграмм и 11 таблиц. Во введении раскрывается актуальность проблемы исследования, разработанность проблематики, ставятся цель и задачи исследования, определяются объект и предмет исследования, формулируются гипотезы, указываются методы и эмпирическая база. Первая и вторая главы включают в себя обзор иностранной и отечественной литературы по теме исследования. Первая глава включает в себя описание представлений о понятии «жизнестойкость» (филологический, философский, психологический, социологический, педагогический аспекты жизнестойкости); рассматриваются этапы становления жизнестойкости лиц с ОВЗ в историческом контексте. Вторая глава включает в себя описание жизнестойкости лиц с ОВЗ в общем, и нарушениями зрения, в частности; жизнестойкость родителей, воспитывающих детей с нарушениями зрения. Выводы по первой и второй главам представляют собой итоги по изучению теоретического материала. Третья глава посвящена эмпирической части исследования. В ней представлено описание организации, процедуры и выборки испытуемых, методов, методик проведенного исследования и результатов, полученных по всем использованным методикам: Тест жизнестойкости С. Мадди (в адаптации Д. А. Леонтьева, Е. И. Рассказовой); Шкала оптимизма и активности (Шкала AOS) (Н. Водопьянова, М. Штейн); Тест-опросник самоотношения (В. В. Столин, С. Р. Пантелеев); Опросник копинг-стратегий СОРЕ Ч. Карвера и др. (в адаптации Гордеевой, Е. Н. Осина, Е. И. Рассказовой и др. (2010)); Опросник «Стиль саморегуляции поведения» (ССП-98); Методика Ш. Шварца (Ценностный опросник (ЦО) Шварца). Также в главе представлены качественный и корреляционный анализ результатов исследования. Выводы по главе 3 включают в себя основные результаты эмпирического исследования. В заключении в обобщенном виде изложены результаты теоретической и эмпирической частей работы, а также выводы по выдвинутым гипотезам, обоснована практическая значимость исследования и описаны возможные перспективы дальнейшей разработки данной проблематики. / The object of the research is resilience of people with sight disabilities. The subject of the research is predictors of people’s resilience with sight disabilities. The master’s thesis consists of an introduction, three chapters, a conclusion, a list of references (134 sources) and 6 appendixes. The appendixes include the description of resilience components and techniques applied in our research, a letter of information addressed to parents of children who have taken part in our research, a type list designed for choosing its appropriate size, charts contained main qualitative and statistic research results. The master’s thesis contains 124 pages and includes 15 diagrams and 11 charts. The introduction reveals the relevance of the research problem, the scientific development of the problem, the aim and the objectives of the research. The introduction also highlights the object and the subject of our research, the hypothesis of the research, the used methods and the empirical base. Foreign and Russian literature on our research problem is reviewed in the first and the second chapters. The Chapter 1 describes a concept of resilience (its philological, philosophical, psychological, sociological and pedagogic aspects) and reveals the stages of resilience formation of people with disabilities in the historical context. The Chapter 2 describes the resilience of people with disabilities in general and the resilience of people with sight disabilities in particular. The second chapter also highlights the resilience of parents who bring up children with sight disabilities. Conclusions on the first and second chapters are the results of the study of theoretical material. The Chapter 3 is devoted to the empiric part of the research. It presents descriptions of the organization, the sample group of people, the methods and techniques used in the research and the results obtained on Hardiness Test by S. Maddi (adapted by D. Leontjev, E. Rasskasova); AOS by N. Vodopyanova, M. Stein; Self-relation Test by V. Stolin, S. Panteleev; Cope Inventory by C. Carver (adapted by T. Gordeeva, E. Osin, E. Rasskasova and others); Behavioral Self-regulation Style questionnaire; Value Survey by S. Schwartz. The third chapter also demonstrates qualitative and correlation analyses of the research results. The conclusions of Chapter 3 include the main results of the empirical research. The conclusion of master’s thesis generally presents the results of the theoretical and empirical parts of the work. It also describes the conclusions on the developed hypotheses, practical importance of the study and possible prospects for further development of this problem.
244

A ROBUST DIGITAL WIRELESS LINK FOR TACTICAL UAV’S

Takacs, Edward, Durso, Christopher M., Dirdo, David 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / A conventionally designed radio frequency amplifier operated in its linear region exhibits low DC to RF conversion efficiency. Typically, for a power amplifier designed for digital modulation applications, the amplifier is operated “backed-off” from its P1dB point by a factor of 10 or -10 dB. The typical linear amplifier is biased for either Class A or Class A/B operation depending on the acceptable design trade-offs between efficiency and linearity between these two methods. A novel design approach to increasing the efficiency of a linear RF power amplifier using a modified Odd-Way Doherty technique is presented in this paper. The design was simulated, built and then tested. The design yields improvements in efficiency and linearity.
245

Geometric Model for Tracker-Target Look Angles and Line of Sight Distance

Laird, Daniel T. 10 1900 (has links)
ITC/USA 2015 Conference Proceedings / The Fifty-First Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2015 / Bally's Hotel & Convention Center, Las Vegas, NV / To determine the tracking abilities of a Telemetry (TM) antenna control unit (ACU) requires 'truth data' to analyze the accuracy of measured, or observed tracking angles. This requires we know the actual angle, i.e., that we know where the target is above the earth. The positional truth is generated from target time-space position information (TSPI), which implicitly places the target's global positioning system (GPS) as the source of observational accuracy. In this paper we present a model to generate local look-angles (LA) and line-of-sight (LoS) distance with respect to (w.r.t.) target global GPS. We ignore inertial navigation system (INS) data in generating relative position at time T; thus we model the target as a global point in time relative to the local tracker's global fixed position in time. This is the first of three companion papers on tracking This is the first of three companion papers on tracking analyses employing Statistically Defensible Test & Evaluation (SDT&E) methods.
246

A historic overview of oriental solmisation systems followed by an inquiry into the current use of solmisation in aural training at South African universities

Louw, Theunis Gabriël 12 1900 (has links)
Thesis (MMus (Music)) -- Stellenbosch University, 2010. / ENGLISH ABSTRACT: The purpose of the present study is twofold: I. In the first instance, it is aimed at promoting a better acquaintance with and a deeper understanding of the generally less well-known solmisation systems that have emerged within the oriental music sphere. In this regard a general definition of solmisation is provided, followed by a historic overview of indigenous solmisation systems that have been developed in China, Korea, Japan, India, Indonesia and the Arab world, thereby also confirming the status of solmisation as a truly global phenomenon. II. The second objective of the study was to investigate the current use of solmisation, and the Tonic Sol-fa system in particular, in aural training at South African universities. In order to achieve this, an inquiry was conducted by means of a survey which consisted of (a) a survey questionnaire that was sent to designers/instructors/coordinators of aural training modules at relevant South African universities and (b) additional correspondence that was subsequently undertaken with some of these respondents. This was done with the aim of obtaining information regarding the following: (1) the extent to which solmisation is still being employed in this context; (2) which solmisation systems or alternative approaches to solmisation are being used; (3) what the respondents’ personal motivations are for employing or not employing solmisation; (4) what instruction material is being utilised in either regard; and (5) what the respondents’ personal views are regarding the use of solmisation in aural training. The outcome of the survey confirmed that solmisation, and the Tonic Sol-fa system in particular, is still actively being used in aural training at South African universities, while at the same time providing some insight into the general application thereof in this context. On the whole, the survey also affirmed the continued relevance of solmisation, and the Tonic Sol-fa system in particular, both in the broader South African context and specifically within the context of aural training at South African universities, showing that solmisation continues to be regarded as a valuable aid in the instruction of aural training by the majority of the designers/instructors/coordinators of aural training modules that participated in the survey. / AFRIKAANSE OPSOMMING: Die doel van die onderhawige studie is tweeledig van aard: I. In die eerste plek is dit gemik op die bevordering van beter vertroudheid met en ’n grondiger begrip van die oor die algemeen minder bekende solmisasiestelsels wat binne die konteks van oosterse musiek na vore getree het. In hierdie verband word daar ’n algemene omskrywing van solmisasie voorsien, gevolg deur ’n historiese oorsig oor inheemse solmisasiestelsels wat ontwikkel is in China, Korea, Japan, Indië, Indonesië en die Arabiese wêreld, en word die status van solmisasie as ’n wesenlik wêreldwye verskynsel dan ook daardeur bevestig. II. Die tweede doelwit van die studie was om ondersoek in te stel na die huidige gebruik van solmisasie, en die Tonic Sol-fa stelsel in besonder, in gehooropleiding aan Suid-Afrikaanse universiteite. Om dit te bewerkstellig, is ’n ondersoek uitgevoer deur middel van ’n opname wat bestaan het uit (a) ’n opnamevraelys wat gestuur is aan opstellers/dosente/koördineerders van gehoorlopleidingsmodules aan relevante Suid-Afrikaanse universiteite en (b) bykomende korrespondensie wat daaropvolgend onderneem is met van hierdie respondente. Dit is gedoen met die doel om inligting te bekom rakende die volgende: (1) die mate waarin solmisasie nog binne hierdie konteks gebruik word; (2) watter solmisasiestelsels of alternatiewe benaderings vir solmisasie gebruik word; (3) wat die respondente se persoonlike motiverings is vir die gebruik van solmisasie al dan nie; (4) watter onderrigmateriaal daar in beide gevalle gebruik word; en (5) wat die respondente se persoonlike sieninge is ten opsigte van die gebruik van solmisasie in gehooropleiding. Die uitslag van die opname het bevestig dat solmisasie, en die Tonic Sol-fa stelsel in besonder, steeds aktief gebruik word in gehooropleiding aan Suid-Afrikaanse universiteite, en het terselfdertyd insig gebied in die algemene aanwending daarvan binne hierdie konteks. In sy geheel het die uitslag van die opname dan ook die voortgesette relevansie van solmisasie, en die Tonic Sol-fa stelsel in besonder, in die breër Suid-Afrikaanse konteks sowel as spesifiek binne die konteks van gehooropleiding aan Suid-Afrikaanse universiteite bevestig, en het dit aangetoon dat solmisasie steeds as ’n waardevolle hulpmiddel in die onderrig van gehooropleiding beskou word deur die meeste van die opstellers/dosente/koördineerders van gehoorlopleidingsmodules wat aan die opname deelgeneem het.
247

Three-dimensional scene recovery for measuring sighting distances of rail track assets from monocular forward facing videos

Warsop, Thomas E. January 2011 (has links)
Rail track asset sighting distance must be checked regularly to ensure the continued and safe operation of rolling stock. Methods currently used to check asset line-of-sight involve manual labour or laser systems. Video cameras and computer vision techniques provide one possible route for cheaper, automated systems. Three categories of computer vision method are identified for possible application: two-dimensional object recognition, two-dimensional object tracking and three-dimensional scene recovery. However, presented experimentation shows recognition and tracking methods produce less accurate asset line-of-sight results for increasing asset-camera distance. Regarding three-dimensional scene recovery, evidence is presented suggesting a relationship between image feature and recovered scene information. A novel framework which learns these relationships is proposed. Learnt relationships from recovered image features probabilistically limit the search space of future features, improving efficiency. This framework is applied to several scene recovery methods and is shown (on average) to decrease computation by two-thirds for a possible, small decrease in accuracy of recovered scenes. Asset line-of-sight results computed from recovered three-dimensional terrain data are shown to be more accurate than two-dimensional methods, not effected by increasing asset-camera distance. Finally, the analysis of terrain in terms of effect on asset line-of-sight is considered. Terrain elements, segmented using semantic information, are ranked with a metric combining a minimum line-of-sight blocking distance and the growth required to achieve this minimum distance. Since this ranking measure is relative, it is shown how an approximation of the terrain data can be applied, decreasing computation time. Further efficiency increases are found by decomposing the problem into a set of two-dimensional problems and applying binary search techniques. The combination of the research elements presented in this thesis provide efficient methods for automatically analysing asset line-of-sight and the impact of the surrounding terrain, from captured monocular video.
248

An adaptive autopilot design for an uninhabited surface vehicle

Annamalai, Andy S. K. January 2014 (has links)
An adaptive autopilot design for an uninhabited surface vehicle Andy SK Annamalai The work described herein concerns the development of an innovative approach to the design of autopilot for uninhabited surface vehicles. In order to fulfil the requirements of autonomous missions, uninhabited surface vehicles must be able to operate with a minimum of external intervention. Existing strategies are limited by their dependence on a fixed model of the vessel. Thus, any change in plant dynamics has a non-trivial, deleterious effect on performance. This thesis presents an approach based on an adaptive model predictive control that is capable of retaining full functionality even in the face of sudden changes in dynamics. In the first part of this work recent developments in the field of uninhabited surface vehicles and trends in marine control are discussed. Historical developments and different strategies for model predictive control as applicable to surface vehicles are also explored. This thesis also presents innovative work done to improve the hardware on existing Springer uninhabited surface vehicle to serve as an effective test and research platform. Advanced controllers such as a model predictive controller are reliant on the accuracy of the model to accomplish the missions successfully. Hence, different techniques to obtain the model of Springer are investigated. Data obtained from experiments at Roadford Reservoir, United Kingdom are utilised to derive a generalised model of Springer by employing an innovative hybrid modelling technique that incorporates the different forward speeds and variable payload on-board the vehicle. Waypoint line of sight guidance provides the reference trajectory essential to complete missions successfully. The performances of traditional autopilots such as proportional integral and derivative controllers when applied to Springer are analysed. Autopilots based on modern controllers such as linear quadratic Gaussian and its innovative variants are integrated with the navigation and guidance systems on-board Springer. The modified linear quadratic Gaussian is obtained by combining various state estimators based on the Interval Kalman filter and the weighted Interval Kalman filter. Change in system dynamics is a challenge faced by uninhabited surface vehicles that result in erroneous autopilot behaviour. To overcome this challenge different adaptive algorithms are analysed and an innovative, adaptive autopilot based on model predictive control is designed. The acronym ‘aMPC’ is coined to refer to adaptive model predictive control that is obtained by combining the advances made to weighted least squares during this research and is used in conjunction with model predictive control. Successful experimentation is undertaken to validate the performance and autonomous mission capabilities of the adaptive autopilot despite change in system dynamics.
249

Lär trummisar som de blivit lärda vad avser noter och gehörsspel?

Dahlstedt, Ludvig January 2017 (has links)
Syftet med denna uppsats är att belysa i vilken mån trumsetslärares tendenser att främja notläsningsbaserade verksamheter kontra gehörsspelsbaserade dito, samt det sätt som dessa olika moment utförs på, är ett resultat av hur de själva blivit undervisade. Tidigare forskning på bland annat spegelneuroner ger vid handen att olika handlingsprogram lärs in omedvetet hos en person vid kontakten med andra människor, för att vid ett senare tillfälle kunna manifesteras i handlingar likartade den som personen iakttagit. Uppsatsen bygger på kvalitativa intervjuer med fyra trumsetslärare från kulturskolor i Storstockholmsområdet. Resultatet visar att respondenterna med viss variation visar relativt stora likheter med sina respektivelärare särskilt med avseende på proportionerna i vilka de använder notspel respektive gehörsspel. Flera av respondenterna utför vidare undervisningsmoment på ett sätt som nästan är identiskt med hur de utförde det som elever. I de fall då respondenterna avviker från sin lärares didaktiska stil, har de snarast lagt till olika moment i undervisningen som inte förekom under deras elevtid.
250

Leitura musical à primeira vista : um estudo com guias de auxílio para estudantes universitários de órgão e piano

Rocha, Alexandre Fritzen da January 2017 (has links)
Leitura musical à primeira vista é uma tarefa complexa que envolve a sobreposição de processos cognitivos, de execução motora, de memória e perceptuais. A habilidade demanda do músico uma ampla base de conhecimento em repertório, estilos e compreensão de códigos musicais. O desenvolvimento da habilidade de ler à primeira vista pode promover o melhoramento de muitas habilidades musicais, incluindo o aumento da consciência musical global. O objetivo deste trabalho é testar o uso de guias para o auxílio no desenvolvimento da tarefa de ler música à primeira vista com estudantes universitários, utilizando a análise musical como ferramenta de auxílio. Esta pesquisa contou com 23 participantes, organistas e pianistas, divididos em dois grupos (experimental e controle), os quais foram submetidos à performance de três trechos musicais inéditos. Os participantes do grupo experimental realizaram a interpretação do segundo trecho com interferência de guias de auxílio para a execução. A maioria dos estudantes demonstrou interesse em desenvolver estudos em leitura à primeira vista. A média de andamento dos sujeitos nos trechos da pesquisa foi 63,5% mais baixa do que o andamento sugerido na partitura A média de erros foi de 8,78 erros por trecho, e os tipos de erros mais cometidos foram os da voz do baixo. As melhores avaliações foram dadas aos estudantes de pós-graduação. 81,82% dos participantes do grupo experimental consideraram que os guias auxiliaram suas execuções. Os resultados mostram que o melhoramento em leitura à primeira vista possivelmente é mais efetivo em um estudo a longo prazo, envolvendo conhecimentos de análise musical, aspectos motores e conhecimento de repertório. Concluímos que o uso dos guias promoveu o melhoramento do andamento da execução dos trechos dos estudantes do grupo experimental e estes sujeitos obtiveram médias menores de erros e as melhores avaliações de juízes externos, além de cometerem menos erros na melodia e na voz do baixo depois de serem submetidos aos guias. / Sight-reading is a complex task that involves overlap of cognitive processes, motor execution, memory and perceptual process. This skill demands broad knowledge in repertory skills, styles and comprehension of musical codes. The development of sight-reading ability can improve several musical skills, including the increase of musical consciousness. The aim of this work is to test the use of musical guides in the development of sight-reading skills with undergraduate students, using musical analysis as a support tool. Twenty-three students participated in this research, among them organists and pianists, from undergraduate, graduate, and extension courses of Federal University of Rio Grande do Sul. The participants were included in two groups, experimental and control, and were asked to perform three unpublished musical excerpts. Those included in the experimental group performed the second excerpt with the use of musical guides. The majority of the students demonstrated interest in developing studies in sight-reading. The average overall tempo of the subjects in the excerpts was 63.5% lower than that suggested in the score The average of errors was 8.78%, and the most frequent errors occurred in the bass voice. The best evaluations were awarded to postgraduate students. 81.82% of the participants considered that the guides helped their performances. Results show that improvement in sight-reading is more likely to occur in a long term study involving, in addition to knowledge of musical analysis, motor aspects and repertory background. The use of guides improved the musical tempo in the students‟ performance in the experimental group. Moreover, the subjects in the experimental group obtained a lower error average and a better rate from the external evaluators. They also made fewer mistakes in the melodic line and the bass voice after using the musical guides.

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