No description available.

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 174-186).

Originally presented as the author's thesis (doctoral)--Delft University of Technology. / Includes bibliographical references (p. [185]-194) and index.

No description available.

Not available / text

This thesis develops a Bayesian inversion algorithm for autonomous underwater vehicle localization, and carries out a study of several factors contributing to localization accuracy in an underwater acoustic positioning system. Specifically, a ray-based algorithm is described that estimates target position through the linearized inversion of transmission arrival time differences, and provides linearized uncertainty estimates for model parameters. Factors contributing to source localization uncertainty considered here included: (1) modelling transmission paths accounting for refraction due to a depth-varying SSP instead of using a constant sound-speed approximation and straight-line propagation, (2) inverting for a potential bias in the measured sound-speed profile, (3) accounting for errors in hydrophone position by including these positions as unknown parameters in the inversion, and (4) applying path-dependent timing correction factors to account for lateral variability in the sound-speed profile. In each case, nonlinear Monte Carlo analysis is applied in which a large number of noisy data sets are considered, to obtain statistical measures of the localization improvement that results by addressing these factors. / Graduate

Thesis (PhD)--University of South Australia, 2002.

This Thesis covers the development of an alternative Global Navigation Satellite System (GNSS) augmentation technology that has become known as the Ground-based Regional Augmentation System (GRAS). GNSS augmentation technologies in support of aviation have largely been developed by countries with large economies such as the USA and members of the European Union. These technologies have focussed on solutions to the specific problems of the host nations, based on the demographics, political and economic factors relevant to them. Outside these countries, the role of GNSS augmentation has largely been ignored, specifically when considering wide area augmentation utilising Satellite Based Augmentation Systems (SBAS). SBAS technologies are expensive, and cannot be justified for nations like Australia with a relatively small number of aircraft, operated in a focussed geographic area. Utilising SBAS services provided by another country introduces cultural, legal and institutional issues that are not always easily addressed. GRAS was derived to provide a cost-effective wide area augmentation capability to nations that lacked the economic ability to field SBAS technologies. This work covers the evolution of the GRAS concept, the construction and testing of the GRAS test bed and its associated test avionics, as well as the development of standards needed to support GRAS as an internationally accepted aviation standard. The major outcome from this work was the confirmation that GRAS could meet the Required Navigation Performance (RNP) standards for Approaches with Vertical Guidance Level 2 (APV-II) as well as all less demanding modes of flight. Results from numerous ground and flight tests conducted under this research program have been reviewed by the International Civil Aviation Organisation (ICAO) GNSS Panel (GNSSP), and been instrumental in the development and validation of Standards and Recommended Practices (SARPs) which promulgate how ICAO standardised systems should perform. The final component of this work describes the project management and technology approval processes needed to get an internationally standardised system into operational use, and the particular problems that a small country like Australia has in progressing these tasks on the World stage.

Thesis (Ph. D.)--Ohio University, June, 1992. / Title from PDF t.p.

Thesis (Ph. D.)--University of Nevada, Reno, 2005. / "May, 2005." Includes bibliographical references. Online version available on the World Wide Web.