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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.
291

Results for Precise GPS Trajectography Computation without Base Station

Morán, Guillermo Martinez 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 / The use of differential GPS post-procesing for precise trajectography computation has been widely used since early 90s. Up to recent dates, installation of a GPS receiver in a well known position (base station) has been mandatory. Operating range from this base station varies from 50 km up to 100 km, depending on the accuracy required, which impose single or dual frequency GPS technique. Nowadays, the huge amount of GPS base stations continuous logging data worldwide have allowed to improve the error models a lot. Using these precise models, it is possible to achieve centimeter accuracy in GPS trajectography by using only one GPS receiver without range to a base station restrictions. This technique is called Precise Point Positioning (PPP). The performance results for PPP obtained after a real 10 flights campaign will be presented.
292

Localization in wireless sensor networks

Cheng, King-yip., 鄭勁業. January 2006 (has links)
published_or_final_version / abstract / Electrical and Electronic Engineering / Master / Master of Philosophy
293

A DAY IN THE LIFE: THE RELATIONSHIPS AMONG NEGATIVE AFFECT, COVITALITY, AND SPATIAL BEHAVIOR MEASURED BY SELF REPORTED SPATIAL BEHAVIOR, AND BY GLOBAL POSITIONING SYSTEM (GPS) TECHNOLOGY

Wolf, Pedro Sofio Abril January 2011 (has links)
The focus of this validation study is to develop and use Global Positioning System (GPS) technology as a tool for psychological research. GPS technology was used to estimate the number of places participants visited over a four day period. To test the convergent validity of this method, this estimate was compared to two self-report methods of measuring the same behavior over the same time frame. All three of these methods were significantly correlated with each other. Results of the split-plot GLM further validated the convergent validity of the GPS method. The test of construct validity was successful when it comes to covitality, however, negative affect did not predict NPV.
294

Exploitation of signal information for mobile speed estimation and anomaly detection

Afgani, Mostafa Z. January 2011 (has links)
Although the primary purpose of the signal received by amobile handset or smartphone is to enable wireless communication, the information extracted can be reused to provide a number of additional services. Two such services discussed in this thesis are: mobile speed estimation and signal anomaly detection. The proposed algorithms exploit the propagation environment specific information that is already imprinted on the received signal and therefore do not incur any additional signalling overhead. Speed estimation is useful for providing navigation and location based services in areas where global navigation satellite systems (GNSS) based devices are unusable while the proposed anomaly detection algorithms can be used to locate signal faults and aid spectrum sensing in cognitive radio systems. The speed estimation algorithms described within this thesis require a receiver with at least two antenna elements and a wideband radio frequency (RF) signal source. The channel transfer function observed at the antenna elements are compared to yield an estimate of the device speed. The basic algorithm is a one-dimensional and unidirectional two-antenna solution. The speed of the mobile receiver is estimated from a knowledge of the fixed inter-antenna distance and the time it takes for the trailing antenna to sense similar channel conditions previously observed at the leading antenna. A by-product of the algorithm is an environment specific spatial correlation function which may be combined with theoretical models of spatial correlation to extend and improve the accuracy of the algorithm. Results obtained via computer simulations are provided. The anomaly detection algorithms proposed in this thesis highlight unusual signal features while ignoring events that are nominal. When the test signal possesses a periodic frame structure, Kullback-Leibler divergence (KLD) analysis is employed to statistically compare successive signal frames. A method of automatically extracting the required frame period information from the signal is also provided. When the signal under test lacks a periodic frame structure, information content analysis of signal events can be used instead. Clean training data is required by this algorithm to initialise the reference event probabilities. In addition to the results obtained from extensive computer simulations, an architecture for field-programmable gate array (FPGA) based hardware implementations of the KLD based algorithm is provided. Results showing the performance of the algorithms against real test signals captured over the air are also presented. Both sets of algorithms are simple, effective and have low computational complexity – implying that real-time implementations on platforms with limited processing power and energy are feasible. This is an important quality since location based services are expected to be an integral part of next generation cognitive radio handsets.
295

Integrating stakeholder requirements across generations of technology

Perz, Michael Robert. 09 1900 (has links)
Complex defense acquisition programs, such as the Global Positioning System program, have many requirements engineering challenges to overcome in order to deliver capabilities to customers and satisfy other stakeholders. To meet these challenges and stay within cost and schedule constraints, engineers and managers need system requirements information organized in a clear, complete, and efficient manner to support decision making. An effective methodology tailored to the needs of the program decision makers will ensure that important information is correct, organized, and readily accessible. The GPS program is implementing a methodology that includes standardized processes across its segments. However, the GPS program refrained from implementing a better requirements engineering approach and using its current requirements engineering tool to take advantage of this approach.
296

Scoring with your Brand : the Case of the Brand Positioning of Brynäs IF

de Greef, Douwe, Kapiteijn, Jesse January 2016 (has links)
Aim: The aim of this study is to identify how a professional ice hockey club with fans nationwide can position its brand successfully and to discover if this is in line with what the consumers think is important in the branding of the club. Method: A mixed method has been used for this case study, in the forms of interviews and a questionnaire. The interviews have been written out in essay form for presentation and analysis of the qualitative data. The quantitative data has been collected and processed with a questionnaire using APSIS and analysed with Microsoft Excel. Results / conclusions: This research has identified a framework containing all factors that influence the perception of the brand by consumers. Evidence was found for all these factors in this research. Furthermore, the most important factors of the branding of a professional ice hockey club with fans nationwide have been highlighted. Consequently, this research shows that the marketers of such an ice hockey club can position their brand by developing clear points-of-difference that stand out from the competition. Suggestions future research: Research into the perception of the sports branding by the younger target group is suggested, as well from people outside Gävle. Furthermore, the research could be conducted in other (ice hockey) clubs. Finally, the research could be conducted again in a few years. Contribution of thesis: This research fills the gap in the literature about the development of a successful brand of a professional ice hockey club with fans nationwide. The main contribution for managers is that brands can only be used to maintain fans, not to attract them.
297

Extending the capabilities of existing Remote Laboratory for Active Noise Control

Konopka, Piotr, Żmuda, Maciej January 2017 (has links)
The aim of the thesis is to upgrade an existing Remote Laboratory for Active Noise Control (ANC) and acoustics experiments providing users with a more authentic real life experience. This is done by designing a solution that allows remote position control of microphones inside a ventilation duct for ANC experiments. The suggested features to be implemented substantially improve the flexibility of the existing remote laboratory, based on the Virtual Instrument System in Reality (VISIR) platform, as well as providing more control over the system as a whole. The work in the project may be divided into the following steps: theoretical design of mechanical and electrical parts of the system along with control algorithms which include a study of similar solutions and related work, implementation of designed system, subsequent testing of the system, connecting the implemented system to the equipment for remote communication and adding the appropriate features to the remote control interface.
298

Standing, being and positioning: A qualitative study of the academic, social and cultural experiences of graduates of a college preparation program during their first year of college

Young, Lydia Rose Lea January 2011 (has links)
Thesis advisor: Audrey Friedman / Evidence suggests that college preparation programs successfully support students through college preparation and application process. However, most research into college preparation programs does not attend to students' collegiate experiences once they leave college preparation programs. This dissertation explored the long-term influence of Small College's College Preparation Program (CPP) on students' collegiate academic, cultural, and social experiences, following college preparation program graduation. This research is a multiple-case study that used phenomenologically oriented interviews. The source of participants was students who completed CPP in 2006 and 2007 and who were enrolled in a university. Using purposeful sampling to achieve maximum variation among CPP graduates, I conducted three tape-recorded interviews of seven participants. Interactive interviews followed Seidman's (1998) recommendations for interview content. Positioning theory was used, in conjunction with social and cultural capital, to analyze data throughout data collection. Positioning theory served as a useful lens for examining the first year college experiences of CPP graduates because it allowed the researcher to explore participant experiences with their agency in mind. Much of the literature on university outreach college preparation programs places students at the center of the research. Often, though, within the research, students are positioned as passive recipients of college preparation services. Viewing the college admissions process as a discourse, participants reflexively self-positioned, but they were also engaged in interactive positioning. In either role, participants assumed an active role, rather than the passive role that most research positions assigns to students. This dissertation finds that participants actively self-positioned as they applied both dominant and non-dominant social and cultural capital during their college preparation and after matriculation. The ability to navigate complex and exclusionary contexts speaks to participants' strengths, perseverance, and motivation. Supportive relationships mitigated the impact of stereotype threat, interpersonal and institutional microaggressions. Moreover, participants self-positioned in ways that built on participants' wealth of insights, experiences, relationships, and capital, leading to academic success. / Thesis (PhD) — Boston College, 2011. / Submitted to: Boston College. Lynch School of Education. / Discipline: Teacher Education, Special Education, Curriculum and Instruction.
299

Estimation of Orientation in a Dual-Tag Ultra Wideband Indoor Positioning System

Johansson, Oscar, Wassénius, Lucas January 2019 (has links)
In this report the feasibility of using a dual-tag setup in an indoor positioning system was investigated. The reason for the dual-tag setup was to be able to estimate both position and orientation. The system was designed using UWB-technology, with an time of flight trilateration algorithm to calculate the position. The orientation was then estimated from the relative position between the two tags. The system was tested both with stationary tags, but also with the tags moving along two paths. These tests were conducted for different separation distance between the tags, namely 20 cm, 30 cm and 40 cm. The result was that the mean position error for stationary tags was less than 8 cm for all separations and the mean orientation error was less than 3$^\circ$ for all separations. For the moving tag tests a decrease of the error in orientation of about 30 \% could be observed for a separation of 30 and 40 cm compared to 20 cm. However this difference is small in absolute values so more tests are needed to draw any conclusion about whether 30 and 40 cm tag separation performs better than 20 cm tag separation. The performance of the system could also be increased further by optimizing the anchor placement as well as the calibration of the antenna delays of the UWB-modules.
300

Principais fatores do projeto de navios aliviadores com sistema de posicionamento dinâmico. / Main factors of ship design with dynamic positioning system.

Moratelli Junior, Lázaro 15 April 2010 (has links)
O presente trabalho discorre sobre os principais fatores que influenciam o projeto do sistema de posicionamento dinâmico (SPD) de um navio aliviador. Os fatores discutidos estão relacionados às questões de confiabilidade de sistemas e às características dos atuadores tipicamente utilizados em embarcações com SPD, tais como, dutos e azimutais. Em relação à confiabilidade de sistemas, os métodos de avaliação por diagramas de blocos e análise de modos de falha e efeitos (FMEA) são discutidos com a aplicação direcionada aos navios aliviadores com SPD. O uso de banco de dados de incidentes de operações com sistemas flutuantes com SPD também é comentado. As alternativas mais utilizadas de arranjo propulsivo para navios aliviadores são apresentadas e analisadas. As interações hidrodinâmicas entre casco-atuador, atuador-atuador e atuador-corrente são apresentadas e comentadas. Ensaios realizados em tanque de provas com propulsores em duto e azimutais instalados em modelos em escala reduzida são apresentados. O texto apresenta a execução de um projeto de dimensionamento propulsivo de um navio aliviador com SPD que opera em águas brasileiras. Para tanto, um procedimento de projeto é sugerido com as seguintes etapas: estudo dos pontos de operação, definição de requisitos de projeto, cálculo de estimativas iniciais, tomada de decisão para a escolha do arranjo propulsivo pelo método de análise hierárquica (AHP), análise de confiabilidade do SPD por FMEA e, por fim, avaliação de desempenho. A avaliação do desempenho do sistema propulsivo projetado é realizada por diagramas de capacidade e simulações dinâmicas. Uma breve comparação entre navios aliviadores com classificações diferentes é realizada e comentada. / This work discusses the main factors that influence the design of dynamic positioning system (DPS) of a shuttle tanker. The factors discussed are related to issues of reliability of systems and the characteristics of the thrusters typically used on DPS vessels, such as ducts and azimuth. Regarding the reliability of systems, methods of reliability evaluation by block diagrams and analysis of failure modes and effects (FMEA) are discussed in the application on DPS shuttle tankers. The utilization of incidents database of offshore vessels with DPS are discussed. The most used alternatives of propulsive arrangement for shuttle tankers are presented and analyzed. Hydrodynamic interactions between hull-thruster, thruster-thruster and thruster-current are presented and commented. Tests with duct and azimuth propellers installed in scale models are presented. This work presents the design of the propulsive subsystem of a DPS shuttle tanker which operates in Brazilian waters. Thus, a design procedure is suggested with the following steps: a study of the operation points, definition of the design requirement, initial estimates, choice the propulsive arrangement by Analytic Hierarchy Process (AHP), reliability analysis of DPS by FMEA and performance evaluation. The performance evaluation of propulsive subsystem is evaluated by wind and current capability plots and dynamical simulations. A brief comparison of shuttle tankers with different classifications is performed and discussed.

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