abstract: In many applications, measured sensor data is meaningful only when the location of sensors is accurately known. Therefore, the localization accuracy is crucial. In this dissertation, both location estimation and location detection problems are considered. In location estimation problems, sensor nodes at known locations, called anchors, transmit signals to sensor nodes at unknown locations, called nodes, and use these transmissions to estimate the location of the nodes. Specifically, the location estimation in the presence of fading channels using time of arrival (TOA) measurements with narrowband communication signals is considered. Meanwhile, the Cramer-Rao lower bound (CRLB) for localization error under different assumptions is derived. Also, maximum likelihood estimators (MLEs) under these assumptions are derived. In large WSNs, distributed location estimation algorithms are more efficient than centralized algorithms. A sequential localization scheme, which is one of distributed location estimation algorithms, is considered. Also, different localization methods, such as TOA, received signal strength (RSS), time difference of arrival (TDOA), direction of arrival (DOA), and large aperture array (LAA) are compared under different signal-to-noise ratio (SNR) conditions. Simulation results show that DOA is the preferred scheme at the low SNR regime and the LAA localization algorithm provides better performance for network discovery at high SNRs. Meanwhile, the CRLB for the localization error using the TOA method is also derived. A distributed location detection scheme, which allows each anchor to make a decision as to whether a node is active or not is proposed. Once an anchor makes a decision, a bit is transmitted to a fusion center (FC). The fusion center combines all the decisions and uses a design parameter $K$ to make the final decision. Three scenarios are considered in this dissertation. Firstly, location detection at a known location is considered. Secondly, detecting a node in a known region is considered. Thirdly, location detection in the presence of fading is considered. The optimal thresholds are derived and the total probability of false alarm and detection under different scenarios are derived. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2016

Orientadores: Milton Mori, Henry França Meier, Udo Fritsching / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-10T10:03:01Z (GMT). No. of bitstreams: 1 Decker_RodrigoKoerich_D.pdf: 3679156 bytes, checksum: 9c914896fd9d31753adf9c1bed158cac (MD5) Previous issue date: 2008 / Resumo: Este trabalho propõe o estudo de estruturas coerentes de larga escala por meio da utilização da metodologia ¿Interparticle Arrival Time¿ (IAT) no escoamento de um jato bifásico. Experimentos foram desenvolvidos em relação a diferentes condições de velocidade inicial com diâmetro médio de partícula igual a 50 µm, e para duas diferentes misturas de partículas, 50 µm e 90 µm, em diferentes proporções, e comparados em relação a perfis de velocidade média, intensidade de turbulência e velocidade RMS. Medidas relacionadas à distribuição IAT foram também adquiridas para todas as condições analisadas. Os experimentos foram desenvolvidos para diferentes posições axiais e radiais a partir da saída do orifício de formação do jato. Perfis radiais de velocidade média, flutuação de velocidade (velocidade RMS), intensidade de turbulência e ¿interparticle arrival time¿ (em termos de distribuição Chi2 e número de desvios) foram obtidos pelo sistema de ¿Phase Doppler Anemometry¿, atravessando o sistema de medição ponto a ponto na direção desejada. Além disto, as variações das condições de velocidade inicial, distribuição de partículas e razão de carga permitem a obtenção de importantes informações em relação às estruturas locais do escoamento e seus efeitos sobre o transporte macroscópico e turbulento de partículas entre o centro do jato e as regiões de contorno do mesmo. Assim é possível identificar que no centro do jato não existe a formação de Estruturas Coerentes de Larga Escala (ECLE), ou seja, o escoamento é dominado por estruturas incoerentes. Existem também fortes indícios de formação de ECLE em uma região radial entre o centro e a região de contorno, sendo estas dependentes da condição inicial de velocidade da fase gás. Além disto, partículas com maior diâmetro suprimem a formação de ECLE. A distribuição IAT prova ser uma ferramenta importante na identificação dos locais onde ECLEs vêm a influenciar a distribuição de partículas, formando ¿clusters¿. A investigação extensiva de dados experimentais em relação ao comportamento da fase dispersa no escoamento gás sólido em um jato pode ser utilizada como uma importante fonte de dados para uma validação detalhada, por meio de simulação numérica, do escoamento disperso bifásico, incluindo as fortes interações entre as fases gás e particulada / Abstract: A study of large scale coherent structures by Interparticle Arrival Time (IAT) of a two phase jet flow is proposed. Measurements were carried out for different initial velocities with 50 µm particle mean diameter, and for two different particle mixtures with mean particle diameter of 50 µm and 90 µm, in different proportions, and analyzed in relation to different variables. Measurements related to IAT were also acquired for all analysis conditions. The experiments were developed for different axial and radial distances from the nozzle outlet. Radial profiles of mean velocity, RMS velocity, turbulence intensity and the IAT (in terms of Chi2 and number of deviation) were measured by a Phase Doppler Anemometry system, traversing the measuring device stepwise in the desired direction. Furthermore, the variation of the initial velocity conditions, particle diameter distributions, and particle loadings yield important information about the local flow structures and its effect on the macroscopic as well as the turbulent particle transport between the jet centre and the outer shear layer. Thus, it is possible to identify that in the centre line of the jet there is no formation of large scale coherent structures (ECLE), i. e., the flow is dominated by incoherent structures. There is also strong evidence of ECLE formation in a radial position between the centre and the outer shear layer of the jet, which are dependent on the gas initial velocity. Furthermore, particles with large diameter suppress ECLE formation. The IAT distribution proofs to be an important tool to identify regions where large scale coherent structures influence the particle distribution and tend to form particle clusters. The derived extensive experimental data set for the particle behaviour at the two-phase jet may serve as a basis for the detailed validation of numerical simulations of dispersed two phase flow behaviour including strong phase interactions between gaseous and particulate phases / Doutorado / Desenvolvimento de Processos Químicos / Doutor em Engenharia Química

O presente estudo teve por objetivo examinar alguns indicadores de regressão e de crescimento do primogênito, longitudinalmente, da gestação aos dois anos de vida do irmão. Foi realizado estudo de caso coletivo, do qual participaram três primogênitos e seus respectivos genitores, em três momentos de análise dos dados (no terceiro trimestre de gestação, aos doze e aos vinte e quatro meses do bebê). Os participantes pertenciam à amostra de um projeto longitudinal maior. Com as crianças, foi aplicado um teste projetivo e as mães e os pais responderam, separadamente, a entrevistas semi-dirigidas. Análise de conteúdo revelou um predomínio de indicadores de regressão do primogênito no período gestacional, tanto a partir do ponto de vista da criança quanto da mãe e do pai. Aos vinte e quatro meses, o teste projetivo revelou indicadores tanto de regressão quanto de crescimento, enquanto para os genitores continuou predominando a regressão. No que tange aos sentimentos maternos e paternos, percebeu-se culpa, preocupação e receio provocados pela regressão do primogênito, durante a gestação e aos vinte e quatro meses. Os genitores parecem ter acolhido mais facilmente a regressão durante a gestação. Ainda que tenham acolhido a regressão aos doze e aos vinte e quatro meses, também estimularam comportamento “de adulto” no primogênito. Aos vinte e quatro meses, predominaram estresse, cansaço, incômodo, impaciência frente à regressão, e orgulho, contentamento e surpresa diante do crescimento. Os resultados revelaram que a regressão foi um meio que o primogênito encontrou para enfrentar o contexto de chegada de um irmão, enquanto que o crescimento revelou a capacidade para novas conquistas ou ainda os custos de assumir novas responsabilidades e o papel de filho mais velho. Assim, tanto as manifestações regressivas quanto as de crescimento oportunizaram um ir e vir saudável e a possibilidade de amadurecimento ou de desenvolvimento rumo à independência. As implicações desses achados que envolvem o processo de tornar-se irmão são destacadas no âmbito da pesquisa e clínico. / The present study aimed to examine longitudinally, from pregnancy to the second child’s second year, some indicators of regression and growth in the firstborn. A collective-case study was carried out, in which three firstborn and their parents took part. The data were collected in three different moments: third trimester of pregnancy, at the baby’s twelfth and twenty-first month. The participants were sellected from a larger longitudinal project. A projective test was used in order to acess the children’s point of view whilst the parents’ point of view was examined through an individual semi-structured interview with each parent. Content analysis revealed a predominance of indicators of regression in the firstborn during pregnancy, both from the children’s and the parents’ point of view. When the firstborn was 24 months old, the projective test revealed indicators of both regression and growth, while from the parents’ perspective, there was still predominance of regression. As far as maternal and paternal feelings are concerned, parents reported guilt, concern and fear, provoked by the firstborn’s regression, during pregnancy and when the second child was 24 months old. The parents seem to have accepted these feelings more easily during pregnancy. Even though they seem to have accepted regression when the second child was 24 months old, they also stimulated “adult-like” behaviour in the firstborn. When the firstborn was twenty-four months, parents reported stress, tiredness, uneasiness, impatience in response to regression in the firstborn, and pride, hapiness and surprise in response to growth. The results revealed that regression was used as a means to cope with the context of a sibling’s arrival whereas growth revealed the firstborn’s capacity for new achievements or the costs involved in assuming new responsibilities and the role of an older child. Therefore, both regressive and growth manifestations enabled a healthy to and fro and the possibility of maturation or development towards independence. The research and clinical implications of these findings that involve the process of becoming a sibling are highlighted.

As wireless devices become more common, the ability to position a wireless device has become a topic of importance. Accurate positioning through technologies such as the Global Positioning System is possible for outdoor environments. Indoor environments pose a different challenge, and research continues to position users indoors. Due to the prevalence of wireless local area networks (WLANs) in many indoor spaces, it is prudent to determine their capabilities for the purposes of positioning. Signal strength and time based positioning systems have been studied for WLANs. Direction or angle of arrival (AOA) based positioning will be possible with multiple antenna arrays, such as those included with upcoming devices based on the IEEE 802.11n standard. The potential performance of such a system is evaluated. The positioning performance of such a system depends on the accuracy of the AOA estimation as well as the positioning algorithm. Two different maximum-likelihood (ML) derived algorithms are used to determine the AOA of the mobile user: a specialized simple ML algorithm, and the space- alternating generalized expectation-maximization (SAGE) channel parameter estimation algorithm. The algorithms are used to determine the error in estimating AOAs through the use of real wireless signals captured in an indoor office environment. The statistics of the AOA error are used in a positioning simulation to predict the positioning performance. A least squares (LS) technique as well as the popular extended Kalman filter (EKF) are used to combine the AOAs to determine position. The position simulation shows that AOA- based positioning using WLANs indoors has the potential to position a wireless user with an accuracy of about 2 m. This is comparable to other positioning systems previously developed for WLANs. / Applied Science, Faculty of / Engineering, School of (Okanagan) / Graduate

[pt] Este trabalho de tese trata do emprego de arranjos de antenas em ambientes de comunicação móvel,dando-se ênfase ao canal de dados reverso do Sistema IS-95. Propõe-se dois estimadores: um para a direção de chegada dos sinais e outro para outros dados. Inicialmente é apresentado um estudo sobre arranjos de antenas e dos principais detalhes do sistema IS-95,especialmente a multiplicidade de acesso via divisão por códigos (CDMA).Aborda-se em seguida o problema da estimação da direção da chegada(DOA), onde se constata que os algoritmos mais conhecidos na literarura especializada, tais como Atraso-e-Soma, Capon, MUSIC e ESPRIT, não apresentam desempenho satisfatório quando empregados em ambiente CDMA. Por isso, propõe-se uma versão do método de estimação de máxima verossimilhança (ML) que utiliza a técnica denominada de EM (-Expectation Maximization-).Seu emprego permitir fracionar o problema de otimização multidimensional gerado pelo estimador ML, em últimas estimações de menor dimensão,simplificando sobremaneira a solução. O estimador proposto além da DOA,permite ainda estimar a atenuação e a defasagem dos sinais incidentes. Através de simulações, constata-se que este estimador EM apresenta um desempenho bastante satisfatório.Para tornar mais completa a análise, faz-se ainda uma comparação da variância do erro na estimação da DOA comolimitante de Cramér-Rao. Em presença de multipercursos, propõe-se quatro versões de um estimador de dados, sendo que uma delas utiliza a estrutura de treliça e objetiva a decisão sequencial dos dados. O desenvolvimento de tais estimadores faz uso de bases de espaços vetoriais para representar as funções de walsh, sendo que as operações aritméticas convencionais . Através de simulações constata-se que essas versões apresentam diferentes relações entre de desempenho e custo computacional, o que permite flexibilidade na adequação do seu emprego. / [en] This thesis deals with antenna arrays when used in mobile communication environment, but the emphasis is on the reverse data link of IS-95. Two estimators are proposed: one for the direction-of-arrival (DOA) and other for the data. Initially, study of the antenna arrays is presented together with the main details of the IS-95 System, especially the details related to the code division multiple access (CDMA). After that, the problem of dirction- of-arrival estimation is discussed. It is shown that mostly of the known estimators, such as Delay-and-Sum, Capon, MUSIC and ESPRIT, do not offer reasonable performance when used in CDMA environment. Therefore, a new Maximum- Likelihood (ML) method is proposed using the so-called Expectation Maximization (EM) algorithm. The main advantage of using such approach is due to the fact that multidimensional optimization required by ML estimation can be split into several problems of lower dimension, thus simplifying the solution. The proposed estimator, besides the DOA estimation, also allows the estimation of attenuation and phase shift of the arriving signals. Simulations show that EM-estimator offers a fair performance when compared to other methods. In order to properly access the statistical significance of this study, the of DOA-estimation erro´s variance is compared with the Cramér-Rao Lower Bound (CRLB). Under a multipath environment, four versions of a data estimator are proposed, and one of them do employ trellis. In the development of such estimators, vector basis are used to represent the Walsh functions and the module-2 operations are replaced by convenient ordinary arithmetic operations. By means of simulation, it is shown that these versions present different levels of performance and computational cost thus allowing to choose the method according to the environmentn conditions. / [es] Este trabajo de tese trata del empleo de arreglos de antenas en ambientes de comunicación móvil, con énfasis en el canal de datos reverso del Sistema IS-95. Se proponen dos estimadores: uno para la dirección de llegada de las señales y otro para el resto de los datos. Inicialmente se presenta un estudio sobre arreglos de antenas y los principales detalles del sistema IS-95,especialmente la multiplicidad de acceso vía división por códigos (CDMA). Se aborda el problema de la estimación de la dirección de llegada(DOA), donde se constata que los algoritmos más conocidos en la literarura especializada, tales como Atraso-y-Suma, Capon, MUSIC y ESPRIT, no tiene un desempeño satisfactorio cuando son utilizados en ambiente CDMA. Por eso, se propone una versión del método de estimación de máxima verosimilitud(ML) que utiliza la técnica denominada de EM (-Expectation Maximization-).Su empleo permite fraccionar el problema de optimización multidimensional generado por el estimador ML, en estimaciones de menor dimensión,simplificando la solución. El estimador propuesto, además de la DOA, permite estimar la atenuación y el defasaje de las señales incidentes. A través de simulaciones, se constata que el estimador EM tiene un desempeño bastante satisfactorio. Para un análisis más completo se comparan las varianza del error en la estimación de la DOA como límite de Cramér-Rao. En presencia de multitrayectoria, se proponen cuatro versiones de un estimador de datos, donde una de ellas utiliza la extructura de celosía y objetiva la decisión secuencial de los datos. El desarrollo de tales estimadores utiliza bases de espacios vectoriales para representar las funciones de walsh, con las operaciones aritméticas convencionales . A través de simulaciones se observa que esas versiones presentan diferentes relaciones entre de desempeño y el costo computacional, que permite flexibilidad en la adecuación de su empleo.

Master of Arts / Department of Geography / John A. Harrington Jr / In late summer and fall, many migratory birds journey south from the North American Great Plains to spend the winter in locations with greater food availability. As spring returns, a combination of genetics and environmental cues trigger these birds to return north to their breeding grounds. Several bird migration phenology studies from Europe, Australia, and the eastern/northern United States have discovered that some bird species are returning earlier in the spring, a change that has often been correlated with a warming climate. This study aimed to be the first to analyze possible changes in both spring bird migration phenology and regional spring climate change in Kansas. First arrival dates (FADs) were collected for thirty bird species, resulting in a database with over 6,000 FAD entries. For northeast Kansas, 1997-2007 median arrival dates were calculated and compared to dates published by Dr. Richard Johnston in 1965. In southcentral Kansas, 1997-2007 and 1947-1967 median arrival dates were calculated and compared. Temperature data from spring (February through May) were also obtained from the National Climate Data Center's United States Historical Climatology Network for all stations within northeast and south central Kansas and temporal trends were analyzed with linear regression analysis. A comparison between median arrival dates in northeast Kansas found that eleven species had altered their arrival date by a potentially significant number of days. Nine of these had advanced their arrival and two showed a delay. In south central Kansas, nine species were shown to have statistically significant differences in median arrival dates between time periods. Six of these showed an advance and three showed a delay. Five species showed the same trend between both regions, with four arriving earlier by an average 9.4 days and one delaying by an average of 4.5 days. Temperature trends for both subregions in Kansas showed significant warming of 1.8-2.6°F (1.0-1.4°C) over the last century, with the largest warming observed in February and associated strongly with increasing minimum temperatures. The results from this study provide the first evidence that some bird species have recently altered the timing of their arrival in Kansas, with a greater shift toward earlier arrival dates. While the majority of these shifts were correlated with spring warming in Kansas, additional research is necessary to determine the precise cause(s) of these phenological shifts. Still, given existing literature and Intergovernmental Panel on Climate Change predictions for continued warming in the next century, continued alterations to bird migration phenology seem likely.

Moderne Experimente in der Kurzzeitphysik erfordern eine hochpräzise Synchronisation der beteiligten Strahlungsquellen, um dynamische Prozesse und atomare Strukturen aufzulösen. Die Komplexität und räumliche Ausdehnung einer linearbeschleuniger-getriebenen Strahlungsquelle wie ELBE verlangt nach neuen Konzepten, um die anspruchsvollen Anforderungen zu erfüllen. Kernbestandteile der vorliegenden Arbeit sind die Konzeption, der Aufbau und die Inbetriebnahme eines gepulsten optischen Synchronisationssystems zur Verteilung eines Phasenreferenzsignals. Dieses System bildet eine wesentliche Grundvoraussetzung für wissenschaftliche Experimente mit einer Auflösung im Bereich von wenigen zehn Femtosekunden. Darüber hinaus wurde der Prototyp eines Ankunftszeitmonitors am ELBE-Beschleuniger entwickelt und charakterisiert. Mit diesem Diagnoseelement wurden erstmals Messungen der Elektronenpulsankunftszeit mit einer Auflösung von wenigen Femtosekunden am ELBE-Strahl möglich. Die implementierte Datenanalyse erlaubt einzelpulsaufgelöste Messzyklen mit bisher unerreichter spektraler Bandbreite am kontinuierlichen (CW) Elektronenstrahl. Ferner wurde eine Methode zur Datenerfassung entwickelt, die unter Verwendung der Lockin-Technik besonders rauscharme Messungen hervorbringen kann. Abschließend wurde der ELBE-Beschleuniger hinsichtlich Ankunftszeit und Energiestabilität umfassend untersucht. Dabei wurden die erweiterten Möglichkeiten, die ELBE als CW-Beschleuniger bietet, ausgeschöpft. Der Fokus lag besonders auf der spektralen Analyse der Störungen bei verschiedenen Kompressionszuständen der Elektronenpulse. Diese methodische Untersuchung wurde sowohl für den thermionischen Injektor als auch für die supraleitende Fotoelektronenquelle durchgeführt. Die präsentierten Messergebnisse ermöglichen ein erweitertes Verständnis für die wirkenden Störmechanismen während der Elektronenpulspropagation und stellen den Ausgangspunkt für systematische Verbesserungen der Strahlqualität dar. Ein beschriebener Grundlagenversuch belegt, wie der ELBE-Elektronenstrahl in Zukunft aktiv stabilisiert werden kann, um die erforderliche Zeitauflösung zu erreichen. Intrinsische Strahlinstabilitäten können dadurch signifikant reduziert werden.

This thesis is related to the field of Sound Source Separation (SSS). It addresses the development and evaluation of these techniques for their application in the resynthesis of high-realism sound scenes by means of Wave Field Synthesis (WFS). Because the vast majority of audio recordings are preserved in twochannel stereo format, special up-converters are required to use advanced spatial audio reproduction formats, such as WFS. This is due to the fact that WFS needs the original source signals to be available, in order to accurately synthesize the acoustic field inside an extended listening area. Thus, an object-based mixing is required. Source separation problems in digital signal processing are those in which several signals have been mixed together and the objective is to find out what the original signals were. Therefore, SSS algorithms can be applied to existing two-channel mixtures to extract the different objects that compose the stereo scene. Unfortunately, most stereo mixtures are underdetermined, i.e., there are more sound sources than audio channels. This condition makes the SSS problem especially difficult and stronger assumptions have to be taken, often related to the sparsity of the sources under some signal transformation. This thesis is focused on the application of SSS techniques to the spatial sound reproduction field. As a result, its contributions can be categorized within these two areas. First, two underdetermined SSS methods are proposed to deal efficiently with the separation of stereo sound mixtures. These techniques are based on a multi-level thresholding segmentation approach, which enables to perform a fast and unsupervised separation of sound sources in the time-frequency domain. Although both techniques rely on the same clustering type, the features considered by each of them are related to different localization cues that enable to perform separation of either instantaneous or real mixtures.Additionally, two post-processing techniques aimed at improving the isolation of the separated sources are proposed. The performance achieved by several SSS methods in the resynthesis of WFS sound scenes is afterwards evaluated by means of listening tests, paying special attention to the change observed in the perceived spatial attributes. Although the estimated sources are distorted versions of the original ones, the masking effects involved in their spatial remixing make artifacts less perceptible, which improves the overall assessed quality. Finally, some novel developments related to the application of time-frequency processing to source localization and enhanced sound reproduction are presented. / Cobos Serrano, M. (2009). Application of sound source separation methods to advanced spatial audio systems [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/8969 / Palancia

The main content of this master’s thesis is design of RNAV SID and STAR routes for Brno Tuřany Airport. The study analyses usage of current conventional instrument arrivals and departures published for the aerodrome and describes its TMA. The new precision RNAV routes and the terminal area are designed based on the indentified information. A detailed construction of the chosen departure procedure is enclosed.

As cities grow, efficient public transport systems are becoming increasingly important. To offer a more efficient service, public transport providers use systems that predict arrival times of buses, trains and similar vehicles, and present this information to the general public. The accuracy and reliability of these predictions are paramount, since many people depend on them, and erroneous predictions reflect badly on the public transport provider. When public transport vehicles move throughout the cities, they create motion patterns, which describe how their positions change over time. This thesis proposes a way of modeling their motion patterns using Gaussian processes, and investigates whether it is possible to predict the arrival times of public transport buses in Linköping based on their motion patterns. The results are evaluated by comparing the accuracy of the model with a simple baseline model and a recurrent neural network (RNN), and the results show that the proposed model achieves superior performance to that of an RNN trained on the same amounts of data, with excellent explainability and quantifiable uncertainty. However, an RNN is capable of training on much more data than the proposed model in the same amount of time, so in a scenario with large amounts of data the RNN outperforms the proposed model.