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Validating MODIS and Sentinel-2 NDVI Products at a Temperate Deciduous Forest Site Using Two Independent Ground-Based Sensors
No full textQuantifying the accuracy of remote sensing products is a timely endeavor given the rapid increase in Earth observation missions. A validation site for Sentinel-2 products was hence established in central Germany. Automatic multispectral and hyperspectral sensor systems were installed in parallel with an existing eddy covariance flux tower, providing spectral information of the vegetation present at high temporal resolution. Normalized Difference Vegetation Index (NDVI) values from ground-based hyperspectral and multispectral sensors were compared with NDVI products derived from Sentinel-2A and Moderate-resolution Imaging Spectroradiometer (MODIS). The influence of different spatial and temporal resolutions was assessed. High correlations and similar phenological patterns between in situ and satellite-based NDVI time series demonstrated the reliability of satellite-based phenological metrics. Sentinel-2-derived metrics showed better agreement with in situ measurements than MODIS-derived metrics. Dynamic filtering with the best index slope extraction algorithm was nevertheless beneficial for Sentinel-2 NDVI time series despite the availability of quality information from the atmospheric correction procedure
BOTDA sensing system employing a tunable low-cost Brillouin fiber ring laser pump-probe source
No full textIn this paper we show a Brillouin optical time-domain analysis (BOTDA) sensing system experiment employing a tunable narrow-linewidth dual pump-probe source based on modified Brillouin ring laser technology. The developed cost-effective source generates a tunable pump-locked probe light, with suitable wavelength shift, large tuning range (~200 MHz), narrow linewidth (<2.5 MHz) and adequate power (~0.5 mW). The developed source was hence employed in BOTDA system experiments providing distributed sensing over ~10 km single mode optical fiber, and attaining strain and temperature resolutions of ~10me and ~0.5 ?C respectively, indicating the pump-probe source as an efficient and cost-effective solution for BOTDA avoiding high-frequency signal generators or complex locking technique
Experiencing Diversity: Complexity, Education, and Peace Construction
No full textThe relationship with diversity is at the core of human experience. In the present contribution, a broad definition of diversity is proposed, which includes, but is not limited to, cultural diversity. The analysis of the experience of diversity is especially focused on youths\u27 attitudes and behaviour. The role of education is also highlighted. Though education is generally considered by the author in its broad sense, namely as the sum of all the elements of reality that in one way or other affect human development, a special emphasis is here given to school. Complexity is a particularly useful epistemological tool in this context, in that, among other things, it indicates the necessity of addressing human issues through newly created and multiple perspectives, as also studies on complex thinking have suggested. Indeed, the main assumption of the presentation is that complexity, diversity, education, and peace building are intimately interrelated. Diversity is one of the essential components of complexity, and considerations regarding the reality of complexity should be the prerequisite of any educational programme and of any effort towards peace building. These reflections partly draw on a number of studies (especially through the use of anonymous open-ended essays) we conducted in Italian secondary schools in the last few years on youth\u27s (aged 9-18) attitudes towards multiculturalism. Some suggestions are also prompted by a brief analysis of a scene from the Italian movie "Al? blue eyes." The scene is located in a secondary school in the outskirts of Rome
Analisi della variabilit? regionale e temporale di Glycaspis brimblecombei in Sardegna
No full textThe red gum lerp psyllid Glycaspis brimblecombei is considered an invasive insect species worldwide. In Italy, after the first recorded in Campania in 2010 on Eucaliptus camaldulensis trees, it spread quickly onto all surrounding Central-Southern regions. In Sardinia, G. brimblecombei was first recorded in 2011, and actually is present all over the regional territory. Prolonged attacks of red gum lerp psyllid can cause both direct and indirect damage on eucalyptus trees, such as plant weakening, developmental reductions and filloptosis, resulting in death within 2-3 years. This aspect is particularly important in Sardinia, where eucalyptus is considered one of the mainly floral resources ensuring approximately 50% of the entire regional honey production. From 2013 to 2015 a monitoring program was carried out at 11 stations located throughout the territory of Sardinia in order to estimate both the dynamics and the population density of preimaginal stages and adults, as well as the general trend of G. brimblecombei over the years. Preliminary results of the three-years monitoring program are reporte
Differences in action style recognition in children with autism spectrum disorders
No full textVitality form is a term, originally introduced by Stern (2010), to describe "how" an action is performed. The capacity to perceive the vitality form of others\u27 actions is a fundamental element of social interactions and a basic way of relating to and understanding others\u27 behaviors. Although vitality forms characterize all human interactions, few studies have addressed their role in social and communicative disorders such as autism. The aim of the present study is to evaluate the ability to recognize different vitality forms during the observation of different motor actions in a group of children with autism spectrum disorders (ASD) compared to typically developing controls (TD). Results show a significant difference between children with ASD and TD in vitality forms recognition. This finding sheds new light on how children with ASD understand others\u27 actions providing new ideas on overall social understanding as well as useful insights for professionals and caregivers alike
Remote sensing in the reflective spectrum: - A powerful and applied technology for terrestrial ecosystem science
No full textNo abstract availabl
Indagini limnologiche recenti sul Lago Maggiore: criticit? emergenti, nuovi approcci di studio e possibili implicazioni gestionali
No full textNot availableI risultati delle ricerche limnologiche recenti sul Lago Maggiore confermano la condizione prossima all\u27oligotrofia e le tendenze evolutive generali. Tuttavia, le indagini indicano anche una sempre maggior rilevanza dei fattori meteo-climatici nel condizionare le dinamiche, a breve e a lungo termine, delle variabili fisiche, chimiche e biologiche nonch? dello stato complessivo dell\u27ecosistema. L\u27analisi delle relazioni tra parametri meteo-climatici e dinamiche termiche e di mescolamento del lago ha messo in evidenza come queste ultime siano influenzate soprattutto dalla variabilit? climatica a scala di bacino, mentre ? minore l\u27effetto delle oscillazioni climatiche a scala continentale (es. NAO): ci? dipende, essenzialmente, dalla posizione geografica del Lago Maggiore, a sud della catena alpina, che forma una sorta di barriera rispetto ai flussi delle masse d\u27aria provenienti dal Nord Europa
Workshop proposal ethical issues of open ended-learning in autonomous robots
No full textNo abstract availabl
BOTDA Sensing Employing a Modified Brillouin Fiber Laser Probe Source
No full textA theoretical and experimental study has been carried out on a tunable dual pump-probe optical source for distributed Brillouin optical time-domain analysis (BOTDA). The developed source exploits a modified Brillouin ring laser technology and is capable of a tuning range of ?200 MHz without using phase-locked loop or optical sideband generation techniques, and exhibits a linewidth smaller than 2.5 MHz and ?0.5 mW power. In BOTDA experiments, the proposed source has demonstrated to be an efficient solution enabling distributed sensing over 10 km single mode fiber with a spatial resolution of ?4 m, and a strain and temperature resolutions of ?10 ?? and ?0.5 ?C respectively
