Possible changes in the intensity of heavy precipitation events at the end of the twenty-first century over the Euro-Mediterranean region are investigated, using a subset of numerical climate simulations taking part to the fifth phase of the Coupled Model Intercomparison Project (CMIP5). As a measure of the intensity associated with heavy precipitation events, we use the difference between the 99th and the 90th percentiles. Despite a slight tendency to underestimate the observed heavy precipitation intensity during summer and to overestimate it during winter, the considered CMIP5 models well represent the observed patterns of the defined 99th–90th percentile metric during both seasons for the 1997–2005 period over the Euro-Mediterranean region. Over the investigated domain, an increase of the width of the right tail of the precipitation distribution is projected in a warmer climate, even over regions where nearly the entire precipitation distribution becomes dryer. This is the case of the European domain within the 45N–55N belt. 相似文献
Objective: The objective of this study was to estimate the safety benefits of in vehicle lane departure warning (LDW) and lane keeping aid (LKA) systems in reducing relevant real-world passenger car injury crashes.
Methods: The study used an induced exposure method, where LDW/LKA-sensitive and nonsensitive crashes were compared for Volvo passenger cars equipped with and without LDW/LKA systems. These crashes were matched by car make, model, model year, and technical equipment; that is, low-speed autonomous emergency braking (AEB) called City Safety (CS). The data were extracted from the Swedish Traffic Accident Data Acquisition database (STRADA) and consisted of 1,853 driver injury crashes that involved 146 LDW-equipped cars, 11 LKA-equipped cars, and 1,696 cars without LDW/LKA systems.
Results: The analysis showed a positive effect of the LDW/LKA systems in reducing lane departure crashes. The LDW/LKA systems were estimated to reduce head-on and single-vehicle injury crashes on Swedish roads with speed limits between 70 and 120 km/h and with dry or wet road surfaces (i.e., not covered by ice or snow) by 53% with a lower limit of 11% (95% confidence interval [CI]). This reduction corresponded to a reduction of 30% with a lower limit of 6% (95% CI) for all head-on and single-vehicle driver injury crashes (including all speed limits and all road surface conditions).
Conclusions: LDW/LKA systems were estimated to lower the driver injury risk in crash types that the systems are designed to prevent; that is, head-on and single-vehicle crashes. Though these are important findings, they were based on a small data set. Therefore, further research is desirable to evaluate the effectiveness of LDW/LKA systems under real-world conditions and to differentiate the effectiveness between technical solutions (i.e., LDW and LKA) proposed by different manufacturers. 相似文献
In last decades, numerous efforts have been carried out by the scientific community to assess the multifunctional role of forests in supporting the forest decision-making processes. Recently developed in Italy, the Forest Landscape Management Planning seems to be the most suitable tool to maintain the sustainability balance between forests and local populations. This research identifies and maps different forest ecosystem functions in a mountain Natura2000 Network site by performing a spatial estimation of forest inventory parameters, and implementing a multi-criteria and multi-level approach. Final results on mapping of forest functions show acceptable values of classification accuracy. 相似文献
Green composites obtained from biodegradable renewable resources have gained much attention due to environmental problems resulting from conventionally synthetic plastics and a global increasing demand for alternatives to fossil resources. In this work we used different cellulose fibers from used office paper and newspaper as reinforcement for thermoplastic starch (TPS) in order to improve their poor mechanical, thermal and water resistance properties. These composites were prepared by using tapioca starch plasticized by glycerol (30 % wt/wt of glycerol to starch) as matrix reinforced by the extracted cellulose fibers with the contents ranging from 0 to 8 % (wt/wt of fibers to matrix). Properties of composites were determined by mechanical tensile tests, differential scanning calorimetry, thermogravimetric analysis, water absorption measurements, scanning electron microscopy, and soil burial tests. The results showed that the introduction of either office paper or newspaper cellulose fibers caused the improvement of tensile strength and elastic modulus, thermal stability, and water resistance for composites when compared to the non-reinforced TPS. Scanning electron microscopy showed a good adhesion between matrix and fibers. Moreover, the composites biological degraded completely after 8 weeks but required a longer time compared to the non-reinforced TPS. The results indicated that these green composites could be utilized as commodity plastics being strong, inexpensive, plentiful and recyclable. 相似文献
Recent concerns about potential climate-change effects on coastal systems require the application of vulnerability assessment
tools in order to define suitable adaptation strategies and improve coastal zone management effectiveness. In fact, while
various research efforts were devoted to evaluate coastal vulnerability to climate change on a national to global level, fewer
applications were carried out so far to develop more comprehensive and site-specific vulnerability assessments suitable to
plan possible adaptation measures at the regional scale. In this respect, specific indicators are needed to address climate-change-related
issues for coastal zones and to identify vulnerable areas at the regional level. Two sets of coastal vulnerability indicators
were selected, one for regional and one for global studies, respectively, concerning the same features of coastal systems,
including topography and slope, geomorphological characteristics, presence and distribution of wetlands and vegetation cover,
density of coastal population and number of coastal inhabitants. The proposed set of indicators for the regional scale was
chosen taking into account the availability of environmental and territorial data for the whole coastal area of the Veneto
region and was based on site-specific datasets characterized by a spatial resolution appropriate for a regional analysis.
Moreover, a GIS-based segmentation procedure was applied to divide the coastline into linear segments, homogeneous in terms
of vulnerability to climate change and sea-level rise at the regional scale. This approach allowed to divide the Veneto shoreline
into 140 segments with an average length of about 1 km, while the global scale approach identified four coastal segments with
an average length of about 66 km. The performed comparison indicated how the more detailed approach adopted at the regional
scale is essential to understand and manage the complexities of the specific study area. In fact, the 25-m DEM employed at
the regional scale provided a more accurate differentiation of the coastal area's elevation and thus of coastal susceptibility
to the inundation risks, compared to the 1-km DEM used at the global level. Moreover, at the regional level the use of a 1:20,000
geomorphological map allowed to differentiate the unique landform class detected at the global level (e.g., fluvial plain)
in a variety of more detailed coastal typologies (e.g., open coast eroding sandy shores backed by bedrock) characterized by
a different sensitivity to climate change and sea-level rise. Accordingly, the information provided by regional indicators
can support decision-makers in improving the management of coastal resources by considering the potential impacts of climate
change and in the definition of appropriate actions to reduce inundation risks, to avoid the potential loss of valuable wetlands
and vegetation and to plan the nourishment of sandy beaches subject to erosion processes. 相似文献
This paper seeks to identify those areas that proved socially vulnerable to the earthquake that struck central Italy on 24 August 2016. The study involved four key steps. First, six relevant social vulnerability indicators were selected, based on previous conclusions in the literature. Second, the indicators were mapped using the inverse distance weighted interpolation method. Third, social vulnerability was assessed according to a spatial combination of the indicators. Fourth, in order to build a heterogeneity map, another approach was employed to represent the spatial variability of social vulnerability and to provide additional information on the synergistic contributions of the indicators. The results indicate that age and accessibility indicators affect the entire region under review, with highly vulnerable zones being close to small historical centres. These findings will be useful to governments, policymakers, and stakeholders with regard to implementing vulnerability mitigation strategies in Italian territories that are highly susceptible to earthquake hazards. 相似文献