Search results for "GPS"
showing 10 items of 139 documents
Relativistic positioning: four-dimensional numerical approach in Minkowski space-time
2011
We simulate the satellite constellations of two Global Navigation Satellite Systems: Galileo (EU) and GPS (USA). Satellite motions are described in the Schwarzschild space-time produced by an idealized spherically symmetric non rotating Earth. The trajectories are then circumferences centered at the same point as Earth. Photon motions are described in Minkowski space-time, where there is a well known relation, Coll, Ferrando & Morales-Lladosa (2010), between the emission and inertial coordinates of any event. Here, this relation is implemented in a numerical code, which is tested and applied. The first application is a detailed numerical four-dimensional analysis of the so-called emissi…
Tomography Application to Complex Seismic Data of the Tjornes Fracture Zone (Iceland)
2014
The Tjornes Fracture Zone (TFZ) is an active seismic zone in Northeast Iceland. It plays a key role to understand the geodynamic movement and location of tectonic plates. However the seismic experiment can not be performed close to earthquake sources, because sources are mainly located in the Greenland Sea. The unusual geological structure of TFZ and the limited conditions of an experiment lead to significant deviations between real observations and the values that are calculated in accordance with theoretical models. Consequently, there is a loss of adequacy and stability of tomography systems. Outcomes of the method, which takes into account this problem, are analyzed in the present chapt…
Continuous Analysis of Running Mechanics by Means of an Integrated INS/GPS Device
2019
This paper describes a single body-mounted sensor that integrates accelerometers, gyroscopes, compasses, barometers, a GPS receiver, and a methodology to process the data for biomechanical studies. The sensor and its data processing system can accurately compute the speed, acceleration, angular velocity, and angular orientation at an output rate of 400 Hz and has the ability to collect large volumes of ecologically-valid data. The system also segments steps and computes metrics for each step. We analyzed the sensitivity of these metrics to changing the start time of the gait cycle. Along with traditional metrics, such as cadence, speed, step length, and vertical oscillation, this system est…
Timed up-and-go performance is associated with objectively measured life space in patients 3 months after ischemic stroke: a cross-sectional observat…
2023
Background Stroke is a common cause of mobility limitation, including a reduction in life space. Life space is defined as the spatial extent in which a person moves within a specified period of time. We aimed to analyze patients' objective and self-reported life space and clinical stroke characteristics. Methods MOBITEC-Stroke is a prospective observational cohort study addressing poststroke mobility. This cross-sectional analysis refers to 3-month data. Life space was assessed by a portable tracking device (7 consecutive days) and by self-report (Life-Space Assessment; LSA). We analysed the timed up-and-go (TUG) test, stroke severity (National Institutes of Health Stroke Scale; NIHSS), and…
RFI: a case study of the University of Palermo
2010
The work shows the results of testing conducted from last years with the GNNS CORS of University of Palermo, in term of radio frequency interference, by a team composed of researchers of Dipartimento di Rappresentazione (DIRAP), Faculty of Engineering of Palermo and to the Laboratory of Physics of the Agenzia Regionale per la Protezione dell’Ambiente (ARPA) of the Sicilian Region. The CORS is first installed inside a scientific network with 9 permanent station located in western Sicily with distance between 22 and 80 kilometres and carry out for real time positioning experience. The main goal of the work is to verify the radio frequency interference which has been subjected CORS in last yea…
Performance assessment of PPP surveys with open source software using the GNSS GPS-GLONASS-Galileo constellations
2020
In this work, the performance of the multi-GNSS (Global Navigation Satellite System) Precise Point Positioning (PPP) technique, in static mode, is analyzed. Specifically, GPS (Global Positioning System), GLONASS, and Galileo systems are considered, and quantifying the Galileo contribution is one of the main objectives. The open source software RTKLib is adopted to process the data, with precise satellite orbits and clocks from CNES (Centre National d&rsquo
Holidays? Not for all. Eagles have larger home ranges on holidays as a consequence of human disturbance
2019
Human-wildlife conflicts are the object of raising concern in conservation biology. People living in urban areas are rapidly increasing worldwide and consequently the temporal pattern of occupation of natural areas for recreation is changing as well, resulting in an ever-increasing concentration of people during weekends and holidays. This is particularly evident in affluent societies, where more recreationists visit natural areas on holidays and weekends, causing disturbance to wildlife in the so-called “weekend effect”. Here, we tested the response to disturbance of 30 Bonelli's eagles tracked by high-frequency GPS/GSM telemetry. We analysed daily home-range size, a measure of changing be…
Individual and Contextual Determinants of Cruise Passengers’ Behavior at Their Destination: A Survival Approach
2020
The proposed study will present an analysis of cruise passengers’ behavior at their destination. Mobility behavior will be analyzed in relation to socio-demographic characteristics through a survival modeling approach. Data collected through GPS devices on cruise passengers’ behavior in the ports of Palermo and Dubrovnik will be analyzed in order to determine similarities and differences among cruise passengers’ behaviors at their destination, according to socio-demographic characteristics. The authors of this chapter contend that the results of this research, involving the processing and the analysis of GPS data, will be of interest from methodological and destination management perspectiv…
Metodi integrati di rilievo per il monitoraggio di eventi franosi
2018
Il contributo riguarda il rilievo di un’area di circa 20 ettari interessata da una imponente frana e ubicata nei pressi del centro abitato di Caronia in Sicilia. La frana ha provocato il crollo e lo spostamento di diverse unità abitative, nonché la quasi totale distruzione delle vie carrabili. Il rilievo è stato condotto con metodi GPS, topografici e laser scanner al fine di verificare la morfologia dell’area successiva all’evento franoso. Il rilievo è stato commissionato dalla Protezione Civile Regionale di Messina ed è stato finalizzato alla programmazione degli interventi di consolidamento del terreno in particolare nelle aree prossime all’edificato. Dalla nuvola di punti generata dalle …
Radiometric and geometric evaluation of the capabilities of the new airborne digital photogrammetric sensors
2008
In this paper the theoretic and practical points of view about the applications of the modern digital airborne sensors in the photogrammetry and remote sensing fields are described. The first part of the paper describes the theoretic matter, the second one shows the first results regarding the carried out elaborations on an image of Palermo acquired by digital airborne sensor LH System ADS40. Besides the research has examined most of sides regarding the trilinear sensor and it has highlighted the capabilities and limitations respect to the traditional analogical system and the matricial CCD sensor.