Search results for "Arriva"
showing 10 items of 60 documents
Individual color variation and male quality in pied flycatchers (Ficedula hypoleuca): a role of ultraviolet reflectance
2002
Bright coloration of males in many animal species has inspired researchers for more than a century. In this field study, we investigated whether color variation between individuals is related to individual quality in pied flycatcher (Ficedula hypoleuca) males in terms of arrival time at the breeding sites. In addition to traditional visual color scoring, plumage color was measured using spectroradiometric measurements between 320 and 700 nm. This range includes the near-ultraviolet waveband from 320 to 400 nm. Males that arrived earlier at breeding sites had higher proportional UV reflectance in the crown and mantle. The proportional UV reflectance in the crown and mantle was not related to…
Tourism Activity of Member States and Romania's Place within the First Five Years after EU Accession
2013
Abstract This paper is a brief statistical analysis of the evolution of tourism in the EU-27 in the first five years after Romania's accession. The analysis was based on official data published by Eurostat regarding the tourist accommodation capacity by categories, the number of arrivals and overnight stays of tourists and non-residents. I highlighted each time Romania's place within Member States, preferring graphics that are more suggestive than synthetic data tables. In conclusions I have highlighted the changes occurred in Romania, far from those expected after five years as a member of the European Union.
Localization of Multi-Class On-Road and Aerial Targets Using mmWave FMCW Radar
2021
mmWave radars play a vital role in autonomous systems, such as unmanned aerial vehicles (UAVs), unmanned surface vehicles (USVs), ground station control and monitoring systems. The challenging task when using mmWave radars is to estimate the accurate angle of arrival (AoA) of the targets, due to the limited number of receivers. In this paper, we present a novel AoA estimation technique, using mmWave FMCW radars operating in the frequency range 77–81 GHz by utilizing the mechanical rotation. Rotating the radar also increases the field of view in both azimuth and elevation. The proposed method estimates the AoA of the targets, using only a single transmitter and receiver. The measurements are…
Classification of Targets Using Statistical Features from Range FFT of mmWave FMCW Radars
2021
Radars with mmWave frequency modulated continuous wave (FMCW) technology accurately estimate the range and velocity of targets in their field of view (FoV). The targeted angle of arrival (AoA) estimation can be improved by increasing receiving antennas or by using multiple-input multiple-output (MIMO). However, obtaining target features such as target type remains challenging. In this paper, we present a novel target classification method based on machine learning and features extracted from a range fast Fourier transform (FFT) profile by using mmWave FMCW radars operating in the frequency range of 77–81 GHz. The measurements are carried out in a variety of realistic situations, including p…
Multi-resolution anisotropy studies of ultrahigh-energy cosmic rays detected at the Pierre Auger Observatory
2017
We report a multi-resolution search for anisotropies in the arrival directions of cosmic rays detected at the Pierre Auger Observatory with local zenith angles up to $80^\circ$ and energies in excess of 4 EeV ($4 \times 10^{18}$ eV). This search is conducted by measuring the angular power spectrum and performing a needlet wavelet analysis in two independent energy ranges. Both analyses are complementary since the angular power spectrum achieves a better performance in identifying large-scale patterns while the needlet wavelet analysis, considering the parameters used in this work, presents a higher efficiency in detecting smaller-scale anisotropies, potentially providing directional informa…
Modeling foreign exchange market activity around macroeconomic news: Hawkes-process approach
2015
We present a Hawkes-model approach to the foreign exchange market in which the high-frequency price dynamics is affected by a self-exciting mechanism and an exogenous component, generated by the pre-announced arrival of macroeconomic news. By focusing on time windows around the news announcement, we find that the model is able to capture the increase of trading activity after the news, both when the news has a sizable effect on volatility and when this effect is negligible, either because the news in not important or because the announcement is in line with the forecast by analysts. We extend the model by considering noncausal effects, due to the fact that the existence of the news (but not…
Development of prediction models for container traffic
2010
The purpose of the work described in this paper is to construct and implement prediction models for optimizing container handling in particular at Cagliari’s Terminal Container. Prediction models are based on heuristic algorithms such as neural networks and classification and regression trees and evolutionary algorithms such as Genetic Algorithms (GA) and Ant Colony Optimization (ACO). These models form part of a Web Oriented Decision Support System, for real time external data acquisition (GPS information, weather information, etc.), providing operators with the information processed in real time. The most commonly used parameter for assessing terminal performance is productivity, namely t…
Trend of inter-arrival times of rainfall events for Italian Sub-Alpine and Mediterranean areas
2011
Visualising maritime vessel open data for better situational awareness in ice conditions
2018
Situational awareness of maritime vessels in ice conditions is important for the operation of supply chains. In the artic sea areas, the ice conditions pose a major challenge for maritime vessels getting stuck in the ice and being significantly delayed in arrival to harbor. Data science and open data provide new opportunities to overcome these challenges. This paper introduces available open data sources and data visualizations that can be used to develop applications, for example, for detecting maritime vessel collision, predicting estimated time of arrival to harbor, as well as maritime vessel route optimization in ice conditions. The paper begins by introducing available open data source…
A new picking algorithm based on the variance piecewise constant models
2022
AbstractIn this paper, we propose a novel picking algorithm for the automatic P- and S-waves onset time determination. Our algorithm is based on the variance piecewise constant models of the earthquake waveforms. The effectiveness and robustness of our picking algorithm are tested both on synthetic seismograms and real data. We simulate seismic events with different magnitudes (between 2 and 5) recorded at different epicentral distances (between 10 and 250 km). For the application to real data, we analyse waveforms from the seismic sequence of L’Aquila (Italy), in 2009. The obtained results are compared with those obtained by the application of the classic STA/LTA picking algorithm. Althoug…