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The emerging GNSS : Galileo, the European alternative to the Global Positioning SystemRey-Ubago, Beatriz del January 2002 (has links)
The Global Satellite Navigation System (GNSS), the core of the International Civil Aviation Organization (ICAO) Communication, Navigation, Surveillance/Air Traffic Management concept is capable of supporting future aviation needs. The implementation of this revolutionary technology however remains overshadowed by a series of complex institutional and legal issues. The extraterritorial control and ownership of existing GNSS systems coupled with the dual character of this technology poses a serious threat to the concept of national sovereignty as traditionally understood. This is further aggravated by the fact that there exists only one de facto GNSS signal provider, thus placed in a position to impose its own conditions without reference to the requirements of the rest of the world. / In an attempt to secure both European political independence and a fair share in the global GNSS market Europe has decided to play an active role by launching Galileo, an autonomous global constellation under the control of civil authorities scheduled to be operational by 2008. / The present thesis analyses the desirability of a suitable legal and institutional GNSS framework to achieve universal acceptance of the GNSS. However, in the context of the present status quo it is unrealistic to expect that the only GNSS signal provider surrender its nationally procured system under the umbrella of an international instrument. National security concerns and industrial policy goals underlie this tendency. The present situation may turn different when the incumbent GPS faces the competition of Galileo, an alternative civil system willing to offer firm legal guarantees of service performance albeit in exchange for a fee. The entire viability of this theory remains however dependent upon the European capability of defining a successful business case for Galileo.
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An Efficient Wi-Fi RSS Indoor Positioning System and Its Client-server ImplementationYu, Yibo 12 December 2013 (has links)
The demand of Indoor Location Based Services LBS has increased over the past years as smart phone market expands. As a result, there's a growing interest in developing efficient and reliable indoor positioning systems for mobile devices. Wi-Fi signal strength fingerprint-based approaches attract more and more attention due to the wide deployment of Wi-Fi access points. Indoor positioning problem using Wi-Fi signal fingerprints can be viewed as a machine learning task to be solved mathematically. This thesis proposes an efficient and reliable Wi-Fi real-time indoor positioning system using machine learning algorithms. The proposed positioning system, together with a location server equipped with the same algorithms, are tested and evaluated in several indoor scenarios. Simulation and testing results show that the proposed system is a feasible LBS solution.
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Investigation on kinematic determination of highway geometric characteristics by attitude GPSAwuah-Baffour, Robert 08 1900 (has links)
No description available.
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The velocity field of the South Island of New Zealand derived from GPS and terrestrial measurementsHenderson, Christopher Mark, n/a January 2006 (has links)
The measurements from eighteen GPS (Global Positioning System) surveys and four terrestrial surveys were used to calculate the velocities of 406 survey stations throughout the South Island, Stewart Island and the southernmost North Island. Repeated GPS measurements are available at 350 stations. The calculation of the velocities for the remaining stations is made possible through the use of terrestrial measurements.
The velocity was modelled under the assumption that the displacements of the stations are either linear with time or linear punctuated by discontinuities. The discontinuous model was used to estimate the coseismic displacements of stations in the vicinity of the 1994 Arthur�s Pass earthquake (M 6.7). The maximum station displacement was estimated to be ca. 40 cm, and significant displacements are seen to a range of ca. 70 km from the earthquake epicentre. Station displacements were also calculated for two later earthquakes in the vicinity of the Arthur�s Pass earthquake, but it was not possible to separate these from the postseismic displacements due to the earlier earthquake.
A continuous velocity field was estimated from the discrete station velocity measurements through a stochastic model based on the concept of minimum curvature. The selection of the basic stochastic model was effectively arbitrary; however, the model was refined to better suit the velocity field in the South Island. This was achieved through estimating the correlation between the velocity components (east and north) and the anisotropy of the velocity field. The stochastic model has the advantage over other models (e.g. polynomials or splines) in that only the probable shape of the velocity field is assumed. Therefore, the shape of the velocity field is not restricted by a priori model assumptions.
The measurement of the differential velocity across the South Island plate boundary between Christchurch and Cape Farewell is less than 85% of the interplate velocity calculated from NUVEL-1A. One possibility is that the NUVEL-1A model may not be an accurate representation of the motion at this plate boundary. Alternatively, deformation (occurring during the period of survey measurements) may extend a total distance of 150 km or more (assuming that the spatial velocity differential is less than 5x10⁻⁷/year) offshore from Christchurch and Cape Farewell. In the southern South Island there is evidence for as much as 22 mm/year of east directed motion being accommodated between Fiordland�s west coast and the stable interior of the Australian Plate. An accretionary wedge has been imaged west of Fiordland (Davey and Smith, 1983; Delteil et al., 1996); therefore, some of this deformation may be related to slip on the subduction interface.
The shear strain rates are clearly influenced by the dominant fault elements in the South Island, i.e. the southern and central Alpine Fault, and the eastern Hope Fault. The maximum measured shear strain rate in the South Island, 6(±1) x10⁻⁷/year, occurs adjacent to the Alpine Fault at (1 70.5°E, 43.3°S), ca. 40 km northeast of Mt Cook, and is coincident with a local dilatational strain rate minimum, -7 (±4.5) x 10⁻⁸/year. This is the only location where the measured strain rate is compatible with strike-slip and dip-slip motion on the Alpine Fault. Shear strain rates decrease eastwards along the Hope Fault: from 5(±0.7) x10⁻⁷/year at the Alpine Fault, to 3(±0.8) x10⁻⁷/year close to the Jordan Thrust. The zone of deformation broadens with a concomitant decrease in shear strain rate, such that within the northeast South Island there is no distinct maximum over any particular fault.
A band of contraction and shear has been imaged at a distance of 100 km southeast of, and parallel to, the Alpine Fault. The deformation at this location may be related to a frontal thrust zone similar to that described in the two-sided wedge models. The band of deformation continues north of Christchurch, intersecting the Porters Pass Fault Zone.
Significant contraction rates are seen in the measurements from four other zones. The first of these is situated towards the northeast (on land) ends of the Clarence, Awatere and Hope Faults. Some of this signal is presumably related to the uplift of the Seaward and Inland Kaikoura Ranges. The three remaining zones of significant negative dilatational strain rate are located north of the Wairau Fault, close to Jackson Bay and within central Otago.
A zone of significant shear strain rate is measured along the eastern side of, and within southern Fiordland. The deformation measurements probably partially reflect the existence of an important fault running through Lake Te Anau, which accommodates the motion of the Fiordland block relative to the Pacific Plate. The remainder may be due to internal deformation of the Fiordland block.
A new velocity differential measurement has been introduced, the rotational excess. This function of the shear strain rate, vorticity and dilatational strain rate should be sensitive to tectonic rotation (as measured by paleomagnetic data). Point estimates of the rotational excess are insignificant throughout the South Island. Also, there are no easily defined regions in which spatially averaged measurements are significant. If the rotational excess is assumed to be a direct measurement of tectonic rotation then the measurements place a bound on the size of the region and the rate at which it rotates. For example, the rate of tectonic rotation within a square region with side lengths of 50 km located adjacent to Cape Campbell is unlikely to be greater than 4°/Ma. However, greater tectonic rotation rates are possible within smaller regions.
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Determination of the geodetic reference frame for Taiwan using GPS observations /Tseng, Ching-Liang. Unknown Date (has links)
Thesis (PhDGeoinformatics)--University of South Australia, 2001.
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Geodetic levelling with the Global Positioning System /Jaksa, Daniel S. Unknown Date (has links)
Thesis (MAppSc (Surveying)) -- University of South Australia, 1993
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802.11 positioning using signal strength fingerprintingSalter, James William, Computer Science & Engineering, Faculty of Engineering, UNSW January 2008 (has links)
The effectiveness of location aware applications is dependent on the accuracy of the supporting positioning system. This work evaluates the accuracy of an indoors 802.11 positioning system based on signal strength fingerprinting. The system relies on an empirical survey of signal strength prior to positioning. During this survey, signal strength recordings are made at a set of positions across the environment. These recordings are used as training data for the system during positioning. In this thesis, two surveying methods, five positioning algorithms, and two spatial output averaging methods are trialled. Accuracy is determined by empirical testing in two separate environments: a 100m square domestic house and the 1,333m square third floor of the University of New South Wales Computer Science and Engineering building. In the two environments, the lowest mean distance errors are 1.25m and 2.86m respectively.
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Moving base INS/GPS vector gravimetry on a land vehicleLi, Xiaopeng , January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 162-170).
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Averaging correlation for weak Global Positioning System signal processingZhu, Zhen. January 2002 (has links)
Thesis (M.S.)--Ohio University, 2002. / Title from PDF t.p.
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The effects of continuous wave interference on Global Positioning System software radio processingGopalan, Kavitha. January 2001 (has links)
Thesis (M.S.)--Ohio University, August, 2001. / Title from PDF t.p.
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