Study of risky situations using experimental data coming from an instrumented bicycle

The aim of this master’s thesis is to study the risky situations of the cyclist when they interact with road infrastructure and other road users as well as the influence of speed on safety. This research activity is linked with the SAFERUP (Sustainable, Accessible, Resilient, and Smart Urban Pavement) European funded project where one of the doctoral candidate has performed experiments on the bicycle simulation at the Gustave Eiffel university in the PICS-L laboratory (Paris) and instrumented bicycle at the Stockholm (Sweden). The approach of the experiment was to hire a number of people who have participated in the riding of the Instrumented bicycle (Stockholm) and bicycle simulator (PICS-L) which were developed by attaching different sensors and devices to measure important parameters of the bicycle riding and their data was collected to analysis in order to understand the behavior of the cyclist to improve the safety. In addition, a mobile eye tracker wore by participants to record the real experiment scenario, and after the end of the trip, each participant shared their remarks regarding their experience of bicycle riding according to different portions of the road infrastructure. In this research main focus is to analyze the relevant data such as speed profiles, video recordings and questionnaire surveys from the instrumented bicycle experiment. In fact, critical situations, where there was a higher probability, were compared with the subjective evaluation of the participant to be conscious of the issues related to the safety and comfort of the cyclist in different road characteristics.

A first survey on the status of the Posidonia oceanica meadow in Calpe Bay (Alicante, Spain).

Posidonia oceanica, endemic seagrass of the Mediterranean Sea, forms extensive meadows. It is included among the Mediterranean protected habitats by the Habitat Directive (92/43/EEC). P. oceanica meadows are exposed to anthropogenic impacts that are more evident in areas close to cities, ports or areas with a large coastal tourism development. Mean exponential decline rate of 5 % yr-1 is estimated for the Spanish meadows. If this trend is maintained, most of the meadows are predicted to halve in shoot density over the next 20 years. The meadows regression can give way to a new regime, which supposes the loss of the multiple services that the meadows provided. It is necessary to recognize situations of stress in time, before irreversible damages and changes towards alternative regimes are evident. This study has been carried out in Calpe Bay, Alicante (Spain), during May and June 2017, with the aim of assessing, for the first time, the status of the P. oceanica meadows providing a baseline data for the future monitoring scheme. The features and status of the seagrass beds have been assessed by physical, physiographical, structural and functional descriptors. The results showed that the health status classification of P. oceanica meadows in Calpe Bay vary between “equilibrium” and “disturbed”. The “disturbed” conditions were observed in a shaded area where it is probably due to the low solar radiance. In a lower limit in a shallow meadow, where it could be due to the combined effect of substrate structure and hydrodynamic regime. Finally in a touristic area where patchy impacts could be attributed to direct human disturbance (e.g. anchoring). Overall the status of P. oceanica meadows in Calpe bay is not worrying. However, it is important to develop monitoring plans to assess the dynamics of the seagrass detecting any early decline symptom in order to act, as soon as possible because, when a regression of a meadow is produced, it could not be recovered at human scales.