Vehicle collision mitigation, cooperative driving, and vehicle-to-vehicle (V2V) and/or vehicle-to-infrastructure (V2I) communication constitute a broad multidisciplinary research field that focuses on improving road safety. Statistics indicate that the primary cause of most road accidents is vehicles' excessive speed and delayed drivers reaction. Thus, road safety can be improved by early warning based on V2V communication. An innovative system called wireless local danger warning (WILLWARN), which is based on recent and future trends of cooperative driving, enables an electronic safety horizon for foresighted driving by implementing onboard vehicle-hazard detection and V2V communication. One of the key innovative features of the proposed system is the focus on low penetration levels in rural traffic by a new message-management strategy that is based on storing warning information in the vehicle and distributing warnings through communication, particularly with oncoming traffic. The system timely warns the driver about a dangerous situation ahead by decentralized distribution of warnings and incident messages via ad hoc intervehicle communication. The WILLWARN system is based on a modular object-oriented architecture consisting of the V2V communication module (VVC), the warning message-management module (WMM), the hazard-detection-management module (HDM), the hazard-warning-management module (HWM), a Global Positioning System (GPS) receiver, and various onboard sensors. In this paper, all system modules, as well as their interoperability, are presented in detail.

A mobile ad hoc network (MANET) is a kind of self-configuring ad hoc network of mobile routers connected by wireless links. Vehicular Ad Hoc Networks (VANETs) are MANETs used for communication among vehicles, and between vehicles and roadside equipment. In order to create a new routing protocol applied to car-to-car networks, we define some parameters to evaluate the efficiency of some of the existing routing protocols. The 802.11p technology designed for VANET was also used, applying the overhaul implementation, which improves the physical and medium access control layer. Our aim is to obtain routing evaluation parameters to be used in a platform between Simulation of Urban Mobility and Network Simulator. We will use these simulations for the implementation and testing of our own geocast routing protocol meant to send information to other vehicles situated in a given geographical position.

We present the age determination of 13 globular clusters that are dynamically associated with the Gaia-Sausage-Enceladus (GSE) merger event, as part of the CARMA project’s effort to trace the Milky Way assembly history. We used deep and homogeneous archival Hubble Space Telescope data, and applied isochrone fitting to derive homogeneous age estimates. We find that the majority of the selected clusters form a well-defined age-metallicity relation, with a few outliers. Among these, NGC 288 and NGC 6205 are more than 2 Gyr older than the other GSE globular clusters at a similar metallicity, and are therefore interpreted as probably having originated in situ. Moreover, NGC 7099 is somewhat younger than the average GSE trend, which suggests a possible alternative dwarf galaxy progenitor, while NGC 5286 is slightly older, as if its progenitor was characterised by greater star-formation efficiency. Another remarkable feature of the resulting age-metallicity relation is the presence of two epochs of globular cluster formation, with a duration of ∼0.3 Gyr each and separated by ∼2 Gyr. These findings are in excellent agreement with the age-metallicity relation recently found for halo field stars, which clearly hints at episodic star-formation in GSE. The age of the two formation epochs is similar to the mean age of the two groups of in-situ globular clusters previously studied by CARMA. These epochs might therefore precisely pinpoint two important dynamical events that Gaia-Sausage-Enceladus had with the Milky Way during its evolutionary history. Finally, we discuss the correlation between the recent spectroscopic determination of Si and Eu, and the clusters age and origin.