Search results for " GPS"
showing 10 items of 60 documents
Spatial and Temporal Variability in Migration of a Soaring Raptor Across Three Continents
2019
Disentangling individual- and population-level variation in migratory movements is necessary for understanding migration at the species level. However, very few studies have analyzed these patterns across large portions of species' distributions. We compiled a large telemetry dataset on the globally endangered egyptian vulture neophron percnopterus (94 individuals, 188 completed migratory journeys), tracked across similar to 70% of the species' global range, to analyze spatial and temporal variability of migratory movements within and among individuals and populations. We found high migratory connectivity at large spatial scales (i.e., different subpopulations showed little overlap in winte…
Broad-front migration leads to strong migratory connectivity in the lesser kestrel (Falco naumanni)
2019
Aim: Migratory animals regularly move between often distant breeding and non‐breeding ranges. Knowledge about how these ranges are linked by movements of individuals from different populations is crucial for unravelling temporal variability in population spatial structuring and for identifying environmental drivers of population dynamics acting at different spatio‐temporal scales. We performed a large‐scale individual‐based migration tracking study of an Afro‐Palaearctic migratory raptor, to determine the patterns of migratory connectivity of European breeding populations. Location: Europe, Africa. Methods: Migration data were recorded using different devices (geolocators, satellite transmi…
Barrier crossings and winds shape daily travel schedules and speeds of a flight generalist
2021
External factors such as geography and weather strongly affect bird migration influencing daily travel schedules and flight speeds. For strictly thermal-soaring migrants, weather explains most seasonal and regional differences in speed. Flight generalists, which alternate between soaring and flapping flight, are expected to be less dependent on weather, and daily travel schedules are likely to be strongly influenced by geography and internal factors such as sex. We GPS-tracked the migration of 70 lesser kestrels (Falco naumanni) to estimate the relative importance of external factors (wind, geography), internal factors (sex) and season, and the extent to which they explain variation in trav…
A webGIS-based system for real time shelf life prediction
2016
Technologies to acquire and monitor changes in the product shelf life were described.Four different SL predictive models were considered.A simulated transport using a prototype of Smart Logistic Unit was analysed.Real time shelf life prediction system was implemented in a webGIS platform. Shelf-life (SL) prediction and Least Shelf-life First Out (LSFO) stock strategy are important factors in perishable food supply chain in order to reduce quality and economic losses.In particular, distribution represents one of the main critical phases in logistic chain management and only the introduction of monitoring procedure can allow a reduction in food losses. Literature shows several mathematical mo…
Accuracy assessment and position correction for low-cost non-differential GPS as applied on an industrial peat bog
1999
A low-cost, non-differentially corrected hand-held GPS receiver was tested on an industrial peat production bog. A correction procedure (‘pseudo-differential correction’) was derived that corrected data points to the nearest position on a line defining the centre of each 15-m wide field. The result was a corrected log of track points for each field for all points lying along the field. It was found that the mean orthogonal distance from a field centreline was linearly correlated with mean uncorrected GPS data error (r 2 0.99) such that as GPS error increased so the accuracy obtained by correction decreased. For a signal with a mean uncorrected error of 30 m it was possible to reduce the err…
Valutazione di sistemi GPS e DGPS combinati con metodi di correzione e sistemi non satellitari
2000
The aim of this work is assess the accuracy of three positiotining systems: a hand-held GPS receiver, tested on itself and together with a pseudo-differential method; a DGPS system; a dead reckoning system. Test results suggest that, for row crops, the "corrected" GPS, the DGPS and the dead reckoning systems satisfy the accuracy requirement for mapping in post-processing soil and crop parameters. It is possible to improve the reliability of position resolution, by using a combined DGPS-dead reckoning system that overcomes the problems of signal weakening and obstruction.
ANALISI DELLE SERIE TEMPORALI DI DATI PROVENIENTI DALLA RETE DI STAZIONI PERMANENTI DELL’UNIPA
2010
La sperimentazione è stata finalizzata all’analisi dei dati acquisiti dalle stazioni permanenti durante l’arco temporale compreso tra la GPS weeks 1490-1542 e corrispondente al periodo tra Luglio 2008 e Luglio 2009. L’analisi di serie temporali di coordinate provenienti da stazioni GNSS risulta un utile strumento da applicarsi, con diverse finalità, sia a monte che a valle del processo di trattamento dei dati misurati. L’analisi di serie temporali trova la sua principale applicazione, in ambito geodetico, nell’analisi delle deformazioni e nella definizione del datum, che, nella più moderna accezione è espresso a quattro dimensioni e considera anche la coordinata temporale. La SP di Alcamo n…
Sperimentazione di smart device equipaggiati con GPS per guide multimediali di siti archeologici
2009
In last years several methodologies have been developed for guided tours of cultural heritage supported by handheld computers (PocketPC). The instruments used for this purpose are pocketPC, possibly equipped with a GPS receiver, which offer contents related to the place where the visitor is at that moment. This paper concerns the design of an innovative multimedia guide running on handheld computers to support the visit of archaeological sites. To that end the performances of various mobile phones and pocketPCs, equipped with low-cost GPS, have been tested; an application software developed by the Palermo research Unit has been installed into these devices to locate in real time the positio…
Rilievo integrato presso Borgo Schirò (PA)
2013
Il lavoro presentato consiste in un rilievo integrato (Topografico/GPS statico/NRTK/Laser) di un piccolo contesto extraurbano siciliano noto per le vicende storiche che portarono alla sua costruzione. Il caso studio è quello di Borgo Schirò, un borgo rurale costruito nel territorio di Monreale (Palermo) a seguito dell’emanazione della legge n.1 del 2 gennaio 1940 che, nel tentativo di superare le politiche del latifondo, offriva ai contadini un luogo vicino ai campi di lavoro nel quale vivere. Il borgo, servito ed attraversato dalla Strada Provinciale n. 99 (di collegamento tra Camporeale, con Corleone e San Cipirrello), in provincia di Palermo, è costituito da sei corpi di fabbrica prospic…
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…