177,047 research outputs found
Tarjeta de G. R. Bonera a Pedro Dorado Montero
No full textTarjeta de D. G. R. Bonera, del Gran Hotel de Gênes [a Pedro Dorado Montero], ofreciéndole el hotel para el congreso de Sociología Italiana
MaccAgri.Soft : Database di macchine agricole e software per il calcolo dei costi di esercizio
No full textMeasuring Safety Performance in the extra-urban Road Network of Lombardy Region (Italy)
No full textRoad Network Screening (RNS) is a process to evaluate the safety performance of the whole road network and identify worst performing roads. Currently, literature provides many models and methods for RNS. Moreover, several frameworks of RNS were issued at the European National Level over time. However, even if sophisticated models and methods could be preferable for their computational accuracy, they may be far from the capabilities of practitioners. In addition, other issues such as availability of operative attributes and data quality and processing persist. For instance, accurate crash location, which is crucial for detailed analyses of high crash rates at some locations, is still an issue: many road administrations pointed out that coordinates miss or are inaccurate in many cases. Within this context, this paper proposes a straightforward operational framework to evaluate safety performance for RNS, using a flexible rationale that integrates crash, traffic, and road data, respectively. More precisely, this framework: (a) handles crash location data without using spatial coordinates; (b) computes the crash rate index at different administrative levels; (c) shows results by Geographic Information System (GIS) maps. This framework is applied to the whole extra-urban road network of the Lombardy Region (Northern Italy) using 30.000+ crash data provided by the Regional Institute for Lombardy Policy Support (PoliS). Road authorities could adopt this framework to perform an accurate safety screening on the road network aimed at rational planning of safety interventions
Collective road transport infrastructural characteristics and spaces in the urban road regulation
No full textSummary-The Road Regulation regulates the characteristics, uses and management of the several road elements for all the allowed traffic components. The collective transport is one of the priority components, especially for urban mobility, but it is generally neglected in the technical specifications of the current Italian Road Regulations. Starting from the critical issues that emerged from the analysis of existing Road Regulations and based on the international literature, professional experience and current legislation, the note provides technical standards about the infrastructural characteristics and the spaces to be allocated to the collective road transport. This is to be intended as a starting reference to develop the specific part of Road Regulation for urban areas. Although not completely exhaustive, the results obtained allow to frame the fundamental elements of the collective transport according to a systemic vision. Also, they recommend strong cooperation between the network managers and the technicians in charge of drafting the Road Regulations, to establish the most suitable standards for the urban area of reference
Evaluating the viability of a Tram-Train system. A case study from Salento (Italy)
No full textTram-Train (TT) combines features of railway and tramway systems by mean of tailored light railway vehicles. Although TT systems offer several benefits such as efficiency, effectiveness, and quality, they also incur some issues (e.g., rolling-stock design) that might discourage city administrations from implementation. Further, whilst this system is quite well-known, the related literature is still scarce and relegated to presenting qualitative descriptions of general features, technical issues, and experiments with some TT components. Detailed viability analyses of TT systems implementation in metropolitan areas and evaluation of their economic feasibility have been poorly investigated. This case study addresses previous gaps by a two-tier framework. The first - a context analysis - focuses on a city's features and applies an analytical hierarchy process resulting in a weighted global score to assess the suitability of the specific context for a TT system. If the city achieves a positive evaluation for implementation (according to the score), then the second tier brings a cost-benefit analysis (CBA) into play to assess the project's economic sustainability. Analysis of the Salento (Italy) metropolitan area proved to be a peculiar case study, as it presented uncommon features for TT system employment compared to ideal scenarios from the literature. Nevertheless, by the context analysis, the area resulted viable for such an innovative and interoperable transport system. Indeed, the results highlighted that resource availability and political strategies were far more relevant in the analysis than the spatial and technical features, as well as the need for improving connections. Next, two TT project alternatives were compared through the CBA, and both resulted in economically sustainable, being the net present value positive, the internal rate of return larger than the discount rate and the benefit-cost ratio larger than one. In addition, a sensitivity analysis was applied for the best alternative. It showed that TT investment costs, the marginal cost of accidents, and the demand shifted from the suburban bus and car, respectively, were reported as critical variables. Nonetheless, no switching values were registered that could realistically threaten the assessment of the economic profitability of the TT project. As far as the authors know, these results provide the first empirical evidence of the TT system's viability and its economic feasibility in a mid-sized city based on the development of previous literature recommendations. Hence, this case study may provide a benchmark tool for policymakers, transit experts and the scientific community to assess TT projects
Refining a crash risk framework for urban bus safety assessment: Evidence from Sardinia (Italy)
No full textAssessing the crash risk on bus routes would be pivotal to increasing the transit system safety. All past studies largely focused on the proposal of some crash risk indexes, and only one (recent) research has computed the bus crash risk in transit services by developing a bivariate (frequency and severity) risk model. Conversely, as far as the authors’ knowledge, no research attempted to quantify the probability of bus crash occurrence as a risk component and present results by geographic information systems. This study covers these gaps by refining an existing framework to better adhere to the original and well-accepted definition of risk. Specifically, it models the bus crash risk on (parts of) routes as a function of the probability of having a crash, the related severity, and exposure terms. Next, (parts of) routes are ranked according to the risk value and classified by a multilevel scale, to show those with the highest risk. Experiments highlight the viability of this framework using 3000+ raw bus crash data records. The results are synthesised by straightforward charts and maps. This framework helps support public transport companies in enhancing safety performance because it could be implemented in a transit safety managerial system for monitoring and certification purposes according to safety norms and EU directives
Estimating operating speed for county road segments – Evidence from Italy
No full textVehicle operating speed is a crucial factor for road safety, as it strictly affects occurrence and severity of crashes. Usually, 85th percentile of the operating speed distributions (i.e., V85) in free-flow traffic condition is widely accepted as a base value of consistency evaluation for homogenous portion of existing roads. Although the computation of V85 is simple, many road authorities cannot collect speed data for each road. Therefore, providing prediction models could be a useful tool to investigate the relationship between V85 and road characteristics. The literature proposed several models to account it. However, to the best of our knowledge, the effects of some road geometric characteristics, road markings and signs, traffic data, type of terrain and the simultaneous consideration of different road categories on the V85 prediction were not completely analyzed. This paper fills this gap by isolating key variables that mostly affect V85. In doing so, 60 000+ car spot speed data were collected along the county road network of the province of Brescia (Italy), and then processed by multiple regression models. The main findings show that V85 increases owing to the presence of a wider or paved shoulder, visible road median markings, a higher number of lanes and a higher percentage of cars with respect to the total traffic flow. Conversely, V85 decreases as the road axis curvature, the number of accesses and rate of forbidden overtaking increase. In addition, the presence of visible road external markings and the surrounding mountainous terrain contribute to decreasing V85. The overall findings may support road authorities to verify roads’ operating conditions and, possibly, adjust the speed limits, especially for existing roads
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