5 research outputs found
Sulle strategie di risposta ai complimenti in un campione diatopicamente orientato
This research aims at exploring the pragmatic strategies of responding to compliments in a speech sample of 654 compliment/response sequences elicited by means of DCT. The corpus has a specific diatopic connotation, since all respondents come from Apulia. For the analysis, the pragmatic categorization proposed for Italian language by Castagneto and Ravetto in 2015 has been adopted. Within the sample, both mitigation and reinforcement strategies coexist, although they are not equally distributed among the informants. The results reveal the presence of cross-gender and cross-ages differences. In details, males tend to use more Limited Acceptance than female ones, while younger women show a strong preference for Direct Acceptance, especially by Thanking and Reassurance Request. Differently, older female informants present a greater degree of Limited Acceptance and a wider use of avoidance strategies, such as Deflection or Discredit.
How to evaluate the surface heat loss and closely follow the evolution of solphataric activity by integrating satellite data and ground measurements to the thermal monitoring of a closed conduit: The case of the active crater at La Fossa (Island of Vulcano, Italy)
The aim of volcanic surveillance is to interpret the observational data in order to highlight changes of activity
and possibly to define the risks for human health and activities. Current satellite missions, providing imagery
in the TIR region at high spatial resolution, offer to volcanic surveillance the possibility to estimate the surface
temperature and highlight surface changes, related to the buried energy sources. Actually the remote sensing
allows repeating the acquisitions in time, with a more convenient cost to benefit ratio, than the direct surveys could
do. Moreover, thanks to the widest areal coverage provided by satellite images, remote sensing dataare able to
identify the areal changes of thermal anomalies all over the volcanic system.. As regards the Island of Vulcano, the
acquisition from LANDSAT and from ASTER (NASA-TERRA), provide thermal data by IR channels, to monitor
the evolution of the surface temperatures on the cone.
The La Fossa cone of Vulcano (Aeolian Arc) has been monitored by the INGV observational network, since
the eighties. The geochemical network, includes, beside many other monitored parameters, also the output
temperature of high temperature fumaroles located on the summit crater. The historical thermal monitoring has
been based on contact sensor, either in the fumaroles (maximum measured temperature 670 C) and in the steam
heated areas (maximum measured temperature 100 C). Within the steam heated ground, the INGV monitoring
system consists in a data-logger storing the ground temperature at fixed time interval (1 h) on 4 points, lying along
the main direction of diffuse heat flux on a shallow vertical profile of soil.
In this work analysis and the comparison of about twenty years of nighttime satellite data and twenty-five years of
ground measurements are presented. The choice to process only nighttime satellite data is due to not presence of
the solar contamination and the obtained temperature has acceptable values in the normal ground surface heated
only by the sun radiation. This long term monitoring of high temperature fumaroles holds a good potential to
improve the interpretation of many surface phenomena occurring in any active volcanic area.
To improve the systematic use of satellite data in the monitor procedures of Volcanic Observatories a suitable
integration and validation strategy is needed, also considering that current satellite missions do not provide TIR
data with optimal characteristics to observe small thermal anomalies that may indicate changes in the volcanic activity. For example, to observe small thermal anomalies and also to detect the effect of different moisture contents on a short optical path (about 1m), proximal IR thermo-camera images of the fumarole fiels have been taken at different times (during daytime and nighttime), and the results have been compared. The analysis of data by proximal IR thermo-camera images could supply either an intermediate observational scale. Moreover they would provide also an intermediate instrumental resolution between the ground measurements by contact sensors and indirect remote sensing data by satellite monitoring, to get comparison of results and validation strategies, more easy.PublishedVienna, Austria4V. Processi pre-eruttiv
Analysis of Thermal Anomalies in Volcanic Areas Using Multiscale and Multitemporal Monitoring: Vulcano Island Test Case
Surface temperatures derived by 208 ASTER and L8 satellite imagery were analysed to test multiscale and multitemporal capability through available sets of thermal data to support the volcanic monitoring of Vulcano Island in Italy. The analysis of thermal historical series derived by ASTER and L8 shows that two are the main thermally active areas: La Fossa crater and the mud pool of Fangaia. In this work we aimed to assess the correlation between the satellite-retrieved temperatures with those measured during the daytime ground field campaign conducted within the same time period and, in particular cases, simultaneously. Moreover, nighttime data acquired by an airborne and field campaign were processed with the same methodology applied to satellite data for a multiscale approach verification. Historical meteorological data acquired from a weather station were also considered. Statistically significant correlations were observed between nighttime acquisitions and meteorological data. Correlations were also significant for temperature measured during the airborne campaign, while differences up to 50% with daytime acquisition during the ground field campaigns were observed. The analysis of the results suggests that within nighttime data acquisition, differences between satellite-derived temperatures and ground temperature measurements are considerably reduced; therefore nighttime data acquisition is recommended to detect thermal anomalies