Search

Urban growth originates multiscale spatial patterns, such as those of transportation networks. Here, the public transportation network (PTN) of the city of Lisbon is analysed from 1901 to 2015, employing several mathematical tools. In a first stage, the fractal dimension and the fractional entropy are used to quantify the evolution of the structure of the PTN in space and time. In a second stage, the PTN is analysed adopting additional information, namely considering different levels of the network based on transportation schedule and passenger capacity, and studying the significance of the distance between stops. Both the fractal dimension and the fractional entropy reveal time patterns compatible with known historical events, showing them to be appropriate for quantifying the growth of the PTN. When the routes' schedules are used to stratify the PTN, not only the fractal behaviour is observed at different levels, but also the evolution of the network in respect to the homogenization of the capacity of different routes. Finally, when the distance between consecutive stops is analysed, a power law behaviour is revealed, as expected from the fractal geometry of the network. This result is then confirmed using the ht-index. [ABSTRACT FROM AUTHOR]

This paper describes a study conducted by the National Laboratory for Civil Engineering of Portugal (LNEC), in cooperation with the Defense University Center at the Spanish Naval Academy and “La Sapienza,” University of Rome, to assess the health and safety conditions of the Noble Hall floor in the São Carlos National Theater (Lisbon, Portugal). In a multidisciplinary approach, extensive fieldwork was carried out. The survey included the location and characterization of beams in the various areas of the floor by using two ground penetrating radar (GPR) systems equipped with two different ground- or air-coupled antennas, local inspection openings to visually assess the geometry, timber species and conservation state of structural members, and an assessment of the conservation state of the timber beam ends using drilling equipment. All the tests performed and the results obtained are presented. The potential of using non-destructive tests for the inspection of timber cultural heritage structures, particularly GPR, is discussed, and some practical recommendations are made. [ABSTRACT FROM AUTHOR]