0000000000090888
AUTHOR
Alessandro Scordo
Use of drones as complement to safety tests on the structures. Study on the chimney stacks of the brownfields
Our cities are rich in historical testimonies of a productive past, many industrial areas that years ago have been a source of income and work are now totally abandoned. Chimneys stacks are an interesting constructive historical episode, because of their representativeness and their materic characteristics. Their size and location, often inside the city centers, sometimes makes them potentially dangerous to safety, so it is necessary to study their conservation status and their resistance to time and stress. The difficulty of finding designs and reliefs and their height and position often make the approach to knowledge difficult, so putting together traditional methods of study with tools u…
Estimation of the time lag occurring between vegetation indices and aridity indices in a Sicilian semi-arid catchment
The evolution of drought phenomena in a Sicilian semi-arid catchment has been analyzed processing both remote sensing images and climatic data for the period 1985-2000. The remote sensing dataset includes Landsat TM and ETM+ multispectral images, while the climatic dataset includes monthly rainfall and air temperature. The results have been specifically discussed for areas where it is possible to neglect agricultural activities and vegetation growth is only influenced by natural forcing. The main outcome of this study is the quantification of the time lag between the remote sensing retrieved vegetation indices and the aridity indices (AIs) calculated from climatic data. Moreover the obtaine…
Monitoring marine water quality of Sicily by means of remotely sensed imagery
Within the framework of the GEOGRID research project, a semi-automatic computational chain has been implemented in order to map the time evolution of marine water quality, around Sicily island, by means of satellite images. To this aim a set of MODIS (TERRA and AQUA) multispectral images has been acquired. An automatic system to georeference and calibrate the images has been implemented. All the procedures to map clorophill-a, total suspended solids and turbidity come from the literature, whereas models parameters have been calibrated by means of in situ measurements.
COMPARISON BETWEEN VEHICLE SPEED PROFILES ACQUIRED BY DIFFERENTIAL GPS AND UAV
Traffic microscopic simulation models are able to represent traffic conditions and their evolution over time. They take into account the geometrical aspects of transport infrastructures, driver behavior and, step by step, the vehicles’ movements on the road network. The most widespread applications of these models are referred to accident management, route guidance problems (possibility of evaluating control strategies in real time), adaptive control of traffic-light and ramp metering (management and control of the ramps and flow). To accomplish this goal observational data of vehicles’ kinematic characteristics have to be acquired. These elements are not always easily available. In scienti…
Gap acceptance analysis in an urban intersection through a video acquired by an UAV
Purpose of this paper is to apply a methodology previously developed to achieve an accurate measurements of the real traffic condition thought the use of a video acquired by an UAV (Unmanned Aerial Vehicle) and a probe vehicle equipped with a differential GPS. The used methodology is not invasive and thus, it doesn't influence the driver behavior. The used equipment must not be compared to the traditional techniques of traffic flow but it can be used for particular situations in which the installation of fixed detectors is not economic. In particular, we have analyzed the gap acceptance for an urban intersection between a main road with dual carriageway and two lanes in one direction, that …
Traffic data acquirement by unmanned aerial vehicle
This paper presents a methodology aimed to acquire traffic flow data through the employment of unmanned aerial vehicles (UAVs). The study is focused on the determination of driving behavior parameters of road users and on the reconstruction of traffic flow Origin/Destination matrix. The methodology integrates UAV flights with video image processing technique, and the capability of geographic information systems, to represent spatiotemporal phenomena. In particular, analyzing different intersections, the attention of the authors is focused on users’ gap acceptance in a naturalistic drivers’ behavior condition (drivers are not influenced by the presence of instruments and operators on the roa…
Pathways and pedestrian crossings: indicators of quality and safety
Pedestrian mobility can be considered an important feature in a new model of town organization. Enhancing pedestrian mobility could bring new life and activities in the old and historic parts of the town reviving their original identities. The planning of new quarters is often performed considering a wide use of private cars, this resulting in urban highways and long and winding local roads hindering pedestrian mobility and safe-ty. Town social features and mobility purpose, related to pedestrian age, are important elements to define the Pedestrian Safety Indicators. Using a GIS software, an evaluation of risk was carried out along a main urban road in order to study and develop measures to…
Urban Traffic Analysis through an UAV
Abstract In order to realize a precise and accurate traffic study, a method to evaluate the real traffic flow conditions in urban areas based on videos acquired by an UAV, Unmanned Aerial Vehicle, is proposed. In this way it does not require additional equipment to earth and, not being invasive, does not influence the driver behavior. This paper presents the results obtained in terms of vehicular traffic flow along a way in the city of Palermo. The results have been compared to experiments using macroscopic simulation models and the eventually differences have been discussed.