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Made available in DSpace on 2014-06-12T16:29:37Z (GMT). No. of bitstreams: 2 arquivo4899_1.pdf: 1436492 bytes, checksum: 12dbd06b3e062a6e1bc78107378d7aef (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2004 / O cadastro tem se consolidado como um sistema de informações territoriais fundamental para o desenvolvimento econômico dos países, utilizado pelos setores público e privado para o planejamento urbano e rural, aperfeiçoamento de sistemas tributários, gerenciamento territorial e monitoramento ambiental. Em 2001, foi sancionada a Lei 10.267/2001, que estabeleceu a exigência de georreferenciamento dos imóveis rurais, o estabelecimento de um intercâmbio sistemático de informações entre o cadastro e o registro de imóveis e a criação do Cadastro Nacional de Imóveis Rurais CNIR. Nessa pesquisa avaliou-se a qualidade da determinação das coordenadas de pontos limites de propriedades, obtidas através da integração de métodos de levantamento, para atender às exigências da Lei 10.267/01, considerando-se a realidade atual no Brasil. Os métodos de levantamento cadastral foram detalhados e experimentos realizados, com ênfase na aplicação de métodos combinados, taqueometria eletrônica e posicionamento com GPS. Analisou-se, ainda, a adequação do Sistema Geodésico Brasileiro - SGB, para o georreferenciamento dos imóveis rurais com a precisão posicional definida após a lei. Com respeito à qualidade da medição dos limites de propriedade, o estudo propõe e detalha a aplicação do Método dos Mínimos Quadrados MMQ e da lei de propagação de erros. Esses procedimentos são necessários para o atendimento ao princípio da vizinhança, exigido em levantamentos cadastrais, e para a obtenção de indicadores da incerteza posicional na determinação das coordenadas dos pontos que caracterizam geometricamente os limites das parcelas. Os resultados demonstram a urgência da densificação do SGB e a adequação da utilização de receptores GPS de uma freqüência para a obtenção de coordenadas de limites com precisão melhor que 50cm

Die Nutzung verfügbarer Radverkehrsdaten auf GPS-Basis stellt eine preisgünstige Möglichkeit für Kommunen dar, einen Überblick über das Nutzungsverhalten ihrer Radfahrenden zu erhalten. Mit den vorliegenden Ergebnissen soll eine Lücke bei der Interpretation von GPS-basierten Daten geschlossen werden. Die Radfahrtypologie auf Basis des geäußerten Verhaltens kann dabei helfen, GPS-Daten auch ohne detaillierte Kenntnisse der zugrundeliegenden Nutzergruppen zielgenauer zu interpretieren. Damit können zukünftig Kommunen die Potenziale entstehender oder bereits vorhandener Angebote an GPS-Radverkehrsdaten zielführender nutzen und ihre Radverkehrsinfrastruktur besser darauf abstimmen. In einem ersten Schritt wurde auf Basis einer Befragung eine empirisch belegte und wissenschaftlich hergeleitete multidimensionale Typologisierung von Radfahrenden erstellt. Anschließend wurde eine umfangreiche heterogene Probandengruppe mit unterschiedlichen soziodemografischen Ausprägungen mit Geräten für die Aufzeichnung ihrer Radrouten ausgestattet. Das auf diesem Weg erhobene Radverkehrsverhalten wurde, gestützt durch kontinuierliche begleitende Befragungen, ausgewertet und anhand unterschiedlicher Indikatoren beschrieben. Damit wurden Präferenzen einzelner Gruppen, z. B. im Hinblick auf Geschwindigkeit, Streckenlänge, Typ der Radverkehrsinfrastruktur, Fahrtzweck oder Routenwahl identifiziert. Auf Basis einer Onlineumfrage konnten vier unterschiedliche Typen von Radfahrenden beschrieben werden, die sich hinsichtlich der Nutzungshäufigkeit, zurückgelegter Entfernungen, Fahrverhalten, Sicherheitsempfinden, Identifikation als Radfahrerende, Wetterabhängigkeit und in motivationalen Aspekten unterscheiden. Anhand der unterschiedlichen Ausprägungen in diesen Merkmalen werden sie als die ambitionierten, die funktionellen, die pragmatischen und die passionierten Radfahrenden bezeichnet. Bezogen auf das Verkehrsverhalten steigt die Nutzungshäufigkeit von ambitionierten über passionierte und pragmatische Radfahrende an. Funktionelle Radfahrende geben die mit Abstand geringste Fahrradnutzung unter allen vier Typen an. Hinsichtlich der angegebenen Distanzen, die zurückgelegt werden, liegen passionierte, pragmatische und funktionelle Radfahrende dicht beieinander. Ambitionierte Radfahrende gaben dagegen an, deutlich größere Distanzen zurückzulegen. Die Ergebnisse aus der Umfrage zeigten sich in einer anschließenden Felduntersuchung in abgeschwächter Form. Insbesondere der ambitionierte Radfahrtyp lässt sich durch höhere Tageskilometerwerte, Geschwindigkeiten und Beschleunigungen von den anderen Typen abgrenzen. Bei den anderen Typen ist eine Unterscheidung weniger ausgeprägt. Hier zeigte sich, dass vor allem die Zugehörigkeit zu einer bestimmten Altersgruppe einen Einfluss auf das Fahrverhalten hat. In Übereinstimmung mit bisherigen Erkenntnissen zeigte sich, dass mit zunehmendem Alter tendenziell etwas langsamer und stetiger gefahren wird. Ebenso radeln auch weibliche Personen etwas langsamer und stetiger als männliche Radfahrer. In der Nutzerbefragung zeigten sich geringe Unterschiede für die Präferenz bei der Infrastrukturnutzung zwischen den Typen, z.B. bei funktionellen Radfahrenden, die eine getrennte Führung im Seitenraum bevorzugen. In der Feldstudie wurde dies ebenfalls untersucht. Auch hier zeigten sich nur geringe Unterschiede. Die Ergebnisse werden auch vor dem Hintergrund eines, eventuell durch die Versuchssituation veränderten Fahrverhaltens der teilnehmenden Radfahrenden, diskutiert. Es konnte vor allem eine hohe Nutzungsfrequenz und Häufigkeit beobachtet werden, die die angegebenen Werte aus der Typenbefragung übertrafen. Für die Nutzung von GPS-Daten für die Radverkehrsplanung wird aus den Ergebnissen abgeleitet, dass eine mögliche Skalierung beziehungsweise Wichtung von Daten entlang soziodemografischer Faktoren die größten Potenziale bietet.

Indiana University-Purdue University Indianapolis (IUPUI) / The use of Global Positioning Systems (GPS) and/or accelerometers to identify trips and transportation modes such as walking, running, bicycling or motorized transportation has been an active goal in multiple disciplines such as Transportation Engineering, Computer Science, Informatics and Public Health. The purpose of this study was to review existing methods that determined trip and travel mode from raw Global Positioning System (GPS) and accelerometer data, and test a select group of these methods. The study had three specific aims: (1) Create a systematic review of existing literature that explored various methods for determining trip and travel mode from GPS and/or accelerometer data, (2) Collect a convenience sample of subjects who were assigned a GPS and accelerometer unit to wear while performing and logging travel bouts consisting of walking, running, bicycling and driving, (3) Replicate selected method designs extracted from the systematic review (aim 1) and use subject data (aim 2) to compare the methods. The results were be used to examine which methods are effective for various modes of travel.

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In recent years, the rapid decrease in size of personal communication devices has lead to the need for more compact antennas. At the same time, expansion of wireless systems has increased the applications for multi-functional antennas that operate over broad frequency bands or multiple independent bands. The civilian GPS system is quickly becoming the standard for personal and commercial navigation and position location. The difficulty with GPS is that there is no return link. That is, a GPS terminal determines its position, but that position is known only to the terminal user. A return link enables positional information derived from GPS to be communicated to a remote location. This is especially desirable for unmanned terminals. The next wide scale technology area for GPS is the integration of a GPS receiver with some type of wireless service to provide communication of the GPS - derived position as well as messaging. One of the most popular uses for this service is tracking of mobile cargo. This paper presents a design for a compact, low-profile antenna that operates at both the conventional cellular telephone band of 824 to 894 MHz and the civilian GPS L1 frequency of 1575 MHz. The combined antenna unit has a lateral diameter of less than 4 inches (10 cm) and its height is less than 2 inches (5 cm). The integrated unit is a hybrid design of two collocated antennas that operate at the two different bands. The planar inverted F antenna, PIFA, meets the specifications which are required in a reduced size environment. The PIFA is capable of achieving a bandwidth of 8% in the cellular band. The GPS portion of the hybrid unit consists of a dielectrically loaded patch located in a "piggyback" configuration on top of the top PIFA element. Computer simulation and design were performed using a combination of IE3D, a 2.5 dimensional commercial moment method code, and Fidelity, a commercial full 3D finite difference time domain code. Results will be presented from these calculations along with measurements on prototype antennas using both the Virginia Tech outdoor antenna range and the Virginia Tech near-field antenna range. / Master of Science

The Federal Communications Commission (FCC) has adopted regulations requiring wireless communication service providers to provide position location (PL) information for a user requesting E-911 service. The Time Difference of Arrival (TDOA) technique is one of the most promising position location techniques for cellular-type wireless communication systems. The IS-95 Code Division Multiple Access (CDMA) system is a popular choice for the companies deploying new cellular and PCS systems in North America. Hence, the feasibility of TDOA techniques in CDMA systems is an important issue for position location in the wireless systems of the future. This thesis analyzes the performance of TDOA techniques in the CDMA systems. A comparison and assessment of different algorithms for finding the time difference estimates and for solving the hyperbolic equations generated by those estimates has been made. This research also considers a measure of accuracy for TDOA position location method which is shown to be more suitable for CDMA systems and more closely matches to the FCC requirements. Among the other contributions is a proposed method to perform cross-correlations to identify only the desired user's TDOA in a multiuser environment. This thesis also evaluates the feasibility and accuracy of TDOA techniques under varying system conditions that might be encountered in real situations. This includes varying conditions of Additive White Gaussian Noise (AWGN), Multiple Access Interference (MAI), power control and loading. The effect of the mobile position and of different arrangement of base stations on TDOA accuracy is also studied. Performance comparison in AWGN and Rayleigh fading channels is made. The feasibility of using increased power levels for the 911 user in combination with interference cancellation is also studied. The effect of using a single stage of parallel interference cancellation at neighboring cell sites has also been explored. Non-ideal situations such as imperfect power control in CDMA operation has also been investigated in the context of position location. This thesis also suggests amethod to correct TDOA estimation errors in CDMA. It is shown that this improvement can give greatly improved performance even under worst-case situations. Performance comparison of results with and without that modification has also been made under various conditions. / Master of Science

A 12 channel real-time GPS L1 C/A-code software receiver has been implemented on a Desktop with 1.84GHz Intel CPU. The software receiver has the capability to acquire new satellites coming in, keep tracking of satellites in view and give a user solution accuracy of 30 meters. This study also explores a real-time correlator for the GLONASS L1 signals. This software receiver is going to be used for scientific research and education. This work is a part of the ongoing effort to develop a low-cost, flexible, and capable GNSS receiver for use as a scientific instrument and for GNSS receiver technology development. The software receiver developed here makes use of a reconfigurable RF front end called the Universal Software Radio Peripheral (USRP) with a maximum real sampling frequency of 8MHz of complex samples. The USRP uses interchangeable daughter boards to down-convert and digitize RF signals in the range of DC to 2.9GHz, where each daughterboard covers an overlapping subset of this range. This RF front end was chosen for its flexibility and ease of use. The output of the RF front end is 8-bit complex I/Q samples output via a USB cable. The software receiver processing of the RF front-end outputs is accomplished by using bit-wise parallelism, as described in References [1] and [2]. In order to process the incoming RF data in this manner, the 8-bit complex I/Q samples are quantized to two bits. This is performed in the software receiver prior to signal correlation. In-phase and quadrature accumulations are computed using bit-wise parallel techniques, and these accumulations are used to drive code tracking delay-lock loops (DLLs) and carrier tracking phase-lock loops(PLLs). The computation of accumulations and the implementation of DLLs and PLLs for the GNSS ranging signals are detailed in the thesis. The software receiver is developed by C++. It consists of two parts: the software receiver core program and a simple interface. The current software receiver runs under Ubuntu Linux systems, but it is convenient to implement on other Linux systems. The software prerequisites for the software receiver are GNUradio and QT4.0. GNUradio is an open source program which provides the driver for the USRP board. The current version used by the software receiver is GNUradio-3.1.3. The user interface program is developed by using the classes provided by QT4.0. The hardware of the whole system consists of computer with intel 1.84 GHz CPU and 2GHz RAM, GPS and GLONASS antenna, USRP, and analogue signal generator. One problem with the USRP is that its on-board oscillator is not particularly stable in terms of frequency and phase. One solution to this problem is to use a high-quality external oscillator. An Agilent N5181A MXG Analog Signal Generator configured to output a 64MHz signal has been used as an external input clock to the USRP. This oscillator has a stated frequency error of 1 ppm/yr, has decent short-term frequency stability, and has a reasonably low phase noise at 64MHz. The outputs of the USRP board are 8 bits complex data with 4MHz sampling frequency with an intermediate frequency of zero. The input data are re-quantized and pack into 32-bit of integers. The total CPU usage of the software receiver is about 30 ~ 40% of the 1.84GHz CPU. The software receiver is started with a FFT based acquisition. The acquisition results are then used to initialize the receiver. The background search of satellites is accomplished by a serial search of PRN code replicas. The novelty of the the software receiver developed in this study is as follows: first, a reconfigurable RF front end is used which makes the software receiver extendable.Second, The software is developed with C++ in the general Linux system; This will make the software receiver easy to maintain and update. Third, the current software receiver also explores the process of GLONASS L1 signals with bit-wise parallel correlation. / Master of Science

L’objectif principal de l’étude était la quantification de la performance de skieurs de fond à l’aide de données cinématiques obtenues à partir d’un GPS à fréquence d’acquisition de 4Hz (Ublox Xbee) et des enregistrements vidéo. Onze athlètes canadiens en ski de fond (8 hommes et 3 femmes, âge moyen de 22±4 ans) ont réalisés des contre-la-montres en style libre et en technique double poussée. Des analyses de la vitesse, de la fréquence de cycle, de l’amplitude de cycle, de la fréquence cardiaque et du choix technique furent réalisées afin de déterminer leur relation avec la performance (soit le temps total). L’analyse des patrons de vitesse nous permet d’observer des "signatures techniques" en style libre. Selon les résultats, la capacité à atteindre une vitesse maximale élevée et maintenir une vitesse moyenne élevée est un déterminant majeur de la performance, peu importe le choix technique ou la pente. L’utilisation prolongée de la technique G2 induit directement une diminution de la performance, spécialement dans les sections de montée abrupte. L’utilisation prolongée de la technique G3 améliore la performance, surtout en montée. Il existe une relation entre une bonne puissance/force du haut du corps, la performance en double poussée et l’utilisation de la technique G3. Il n’existe pas de relation entre l’amplitude de cycle et la fréquence de cycle et l’amplitude de cycle et la vitesse pour la technique G3. Au sprint final en technique G3, plus la vitesse est élevée, plus la fréquence de cycle l’est aussi. Un pourcentage élevé d’utilisation de la technique G3 correspond à un faible nombre de transitions et à une meilleure performance. De façon générale, on peut affirmer que les sections de montée ont le plus d’influence sur la performance globale. Finalement, en comparant le ski de fond (sur neige) et le ski à roulettes (sur asphalte) en technique G3 et G4, il existe une différence importante pour la fréquence et la durée des cycles; un athlète performant sur l’asphalte en ski à roulettes doit avoir une fréquence de cycle plus élevée pour parcourir la même distance que sur neige en ski de fond. L’analyse et l’interprétation des résultats de cette recherche ont permis d’établir un standard "médaille d’or" de performance, ainsi qu’un profil pour chacun des skieurs, et fût très pratique pour les entraineurs.