71 research outputs found
Spatial modelling of air pollution in urban areas with GIS: a case study on integrated database development
International audienceA wide range of data collected by monitoring systems and by mathematical and physical modelling can be managed in the frame of spatial models developed in GIS. In addition to data management and standard environmental analysis of air pollution, data from remote sensing (aerial and satellite images) can ehance all data sets. In spite of the fact that simulation of air pollutant distribution is carried out by standalone computer systems, the spatial database in the framework of the GIS is used to support decision-making processes in a more efficient way. Mostly, data are included in the map layers as attributes. Other map layers are carried out by the methods of spatial interpolation, raster algebra, and case oriented analysis. A series of extensions is built into the GIS to adapt its functionality. As examples, the spatial models of a flat urban area and a street canyon with extensive traffic polluted with NOx are constructed. Different scales of the spatial models require variable methods of construction, data management, and spatial data sources. The measurement of NOx and O3 by an automatic monitoring system and data from the differential absorption LIDAR are used for investigation of air pollution. Spatial data contain digital maps of both areas, complemented by digital elevation models. Environmental analyses represent spatial interpolations of air pollution that are displayed in horizontal and vertical planes. Case oriented analyses are mostly focused on risk assessment methods. Finally, the LIDAR monitoring results and the results obtained by modelling and spatial analyses are discussed in the context of environmental management of the urban areas. The spatial models and their extensions are developed in the framework of the ESRI's ArcGIS and ArcView programming tools. Aerial and satellite images preprocessed by the ERDAS Imagine represent areas of Prague
Size-dependent stability of ultra-small α-/β-phase tin nanocrystals synthesized by microplasma
Key features of tin, including electronic band structure and opto-electronic properties, are influenced by the crystal structure. Here the authors report a microplasma process for the synthesis of ultra-small tin nanocrystals in which the crystal structure is dependent on crystallite size
Multicriteria analysis for sources of renewable energy using data from remote sensing
Renewable energy sources are major components of the strategy to reduce harmful emissions and to replace depleting fossil energy
resources. Data from remote sensing can provide information for multicriteria analysis for sources of renewable energy. Advanced
land cover quantification makes it possible to search for suitable sites. Multicriteria analysis, together with other data, is used to
determine the energy potential and socially acceptability of suggested locations. The described case study is focused on an area of
surface coal mines in the northwestern region of the Czech Republic, where the impacts of surface mining and reclamation constitute
a dominant force in land cover changes. High resolution satellite images represent the main input datasets for identification of
suitable sites. Solar mapping, wind predictions, the location of weirs in watersheds, road maps and demographic information
complement the data from remote sensing for multicriteria analysis, which is implemented in a geographic information system (GIS).
The input spatial datasets for multicriteria analysis in GIS are reclassified to a common scale and processed with raster algebra tools
to identify suitable sites for sources of renewable energy. The selection of suitable sites is limited by the CORINE land cover
database to mining and agricultural areas. The case study is focused on long term land cover changes in the 1985-2015 period.
Multicriteria analysis based on CORINE data shows moderate changes in mapping of suitable sites for utilization of selected sources
of renewable energy in 1990, 2000, 2006 and 2012. The results represent map layers showing the energy potential on a scale of a few
preference classes (1-7), where the first class is linked to minimum preference and the last class to maximum preference. The
attached histograms show the moderate variability of preference classes due to land cover changes caused by mining activities. The
results also show a slight increase in the more preferred classes for utilization of sources of renewable energy due to an increase area
of reclaimed sites. Using data from remote sensing, such as the multispectral images and the CORINE land cover datasets, can
reduce the financial resources currently required for finding and assessing suitable areas
Nano-hardness, EBSD analysis and mechanical behavior of ultra-fine grain tungsten for fusion applications as plasma facing material
Tungsten and its alloys have been extensively studied in order to be used in plasma facing components for future fusion nuclear reactors such as ITER and DEMO. In this work, an evaluation of nano-hardness, microstructure/texture and mechanical behavior using nano-indentation, electron backscatter diffraction (EBSD) and tensile test was performed. The investigated materials were ultra-fine grain lab-scale tungsten and ITER-specification commercial tungsten products, taken as reference in the as-received and annealed (at 1300 °C for 1 h) conditions. Three ultra-fine grain (UFG) tungsten grades were produced under different spark plasma sintering conditions, namely at 2000 °C and 70 MPa, at 1700 °C and 80 MPa and, finally, at 1800 °C and 80 MPa. EBSD analysis provides very relevant data as it is known that the crystallographic orientation affects some features of the surface damage caused by fusion-relevant plasma exposure. The present results will serve as a reference for future studies that will be carried out using plasma-exposed samples in order to correlate the observed damage with the microstructural characteristics and mechanical behavior
A preliminary catalogue of the Coleoptera (Hexapoda: Insecta) of the Monte Netto Regional Park (Lombardy NE Italy)
The Po Plain (Northern Italy) is one of the most urbanized areas in Europe. In such a territory, where ecosystem degradation reached critical levels and the agricultural matrix is prevailingly intensive, small fragments of hilly oak-hornbeam forests still persist. Examples of well preserved forests of the Po Plain are those of the Monte Netto Regional Park that represents irreplaceable refuges for both sedentary and migratory species. In this paper we present a preliminary list of Coleoptera inhabiting the Park collected during 10 years of field surveys using several sampling techniques (hand netting, beating tray, sight-collecting and collecting under bark; water nets; litter reducers, light traps; aerial sweet-bait trap; cross-vane panel trap, pitfall traps, Malaise traps, window traps, and walking transects). Specific samplings were also made in tree hollows and by car-netting. To date we have identified 834 species belonging to 531 genera and 71 families (several specimens and some families are still undetermined). Among all the species identified, 31 were non-native while 202 were included in the Red List of Italian saproxylic beetles, 12 of which were in threatened category. The high beetle richness and the presence of many endangered species recorded during this survey, emphasises the conservation value of Monte Netto. Moreover, the discovery of species linked to old and stable forest systems, such as Osmoderma eremita, Oxylaemus cylindricus, Pycnomerus terebrans or Xylotrechus antilope suggests how, despite their small size and the fact that they are surrounded by agricultural land, the remaining forest patches of Monte Netto still possess a fair level of naturalness, especially in the internal areas of the larger plots. Future targeted research, also intended to cover other parts of Monte Netto, could increase our present knowledge; however, and at least in the number of families, we do not expect a substantial increase in species richness
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