Risk-minimal routes for emergency cars

The computation of an optimal route for given start and destination in a static transportation network is used in many applications of private route planning. In this work we focus on route planning for emergency cars, such as for example police, fire brigade and ambulance. In case of private route planning typical quantities to be minimized are travel time or route length. However, the idea of this paper is to minimize the risk of a travel time exceeding a certain limit. This is inspired by the fact that the emergency cars have to reach the destination within a legal time. We consider mainly two approaches. The first approach takes into account relevant information to determine the weight, i.e. the desirability of certain edges of a graph during the minimization procedure. One possible risk factor to be aware of would be a suddenly jammed single-lane road on which the emergency car has no chance to make use of the benefits of the siren for instance. The same holds for full-closure situations and railroad crossings. We present a catalogue of risk factors along with an appropriate algorithm for practical route planning in emergency situations. The second one takes into account a weekly updated set of probe-vehicle data for each minute of the week along with data of current travel times. Comparing those travel-time data allows calculation of the associated risk for traveling certain edges of a route in a road network. We expect our algorithm to be a major advancement especially for destinations that lie outside the typical region travelled weekdays. In this case the automatic route planning naturally goes along with an additional gain of time

Report on 4th Workshop of Topic Working Groups

This deliverable contains a brief, concise summarization of the fourth cycle of Topic Working Group (TWG) Workshops in the DAREnet EU project. In this cycle the project aims to identify and discuss barriers as well as enablers in flood response and flood management together with practitioners with respect to "standards" and "procedures"

Bevorrechtigung von Einsatzfahrzeugen mittels einer dezentralen LSA-Steuerung

Neben der Bevorrechtigung von Einsatzfahrzeugen mit Blaulicht über den Kommunikationsweg der Verkehrsmanagementzentrale wurde in SIRENE ein dezentraler Ansatz über V2X und LTE umgesetzt und untersucht. Der Vortrag beinhaltet Informationen zur Methodik und Umsetzung. Die Ergebnisse befinden sich in einem separaten Vortrag

A smart data approach to traffic safety

This work demonstrates, how a large data-base of traffic crashes can be used to analyze ensemble data. It fused data from the German Unfallatlas (German Crash Database - GCDB) with Open Streetmap (OSM) data (both publicly available), and a database from the German Federal State Northrhine-Westfalia (NW) named NWSIB that provides additional information about each intersection, most importantly an estimate of the ADT-values and street view images. The results have to be taken with care, since the quality of the ADT's in the database is hard to control, and because this approach may have assignment errors. The results partially reproduce known findings; however, they allow in principle for a more detailed investigation of the relationship between crash-numbers and ADT-values than is possible with generalized linear models (glm). In line with the call, all the data, as well as the scripts that analyse the data are publicly available -- this text is entirely written in the Rmd format \citep{RStudio2022}, and most computations have been done in R \citep{R2021} and QGIS \citep{QGIS}

Action-points in human driving and in SUMO

When following a vehicle, drivers change their acceleration at so called action-points (AP), and keep it constant in between them. By investigating a large data-set of car-following data, the state- and time-distributions of the APs is analyzed. In the state-space spanned by speed-difference and distance to the lead vehicle, this distribution of APs is mostly proportional to the distribution of all data-points, with small deviations from this. Therefore, the APs are not concentrated around certain thresholds as is claimed by psycho-physical car-following models.Instead, small distances indicate a slightly higher probability of finding an AP than is the case for large distances. A SUMO simulation with SUMO's implementation of the Wiedemann model confirms this view: the AP's of the Wiedemann model follow a completely different distribution than the empirical ones

Bevorrechtigung von Einsatzfahrzeugen mittels einer dezentralen LSA-Steuerung via V2X-Kommunikation

Neben der Bevorrechtigung von Einsatzfahrzeugen mit Blaulicht über den Kommunikationsweg der Verkehrsmanagementzentrale wird in SIRENE ein dezentraler Ansatz über V2X umgesetzt und untersucht. Das Poster beinhaltet Informationen zur Methodik und Umsetzung

Analyse von Korrelationen zwischen Unfallzahlen und Merkmalen der Infrastruktur mit Hilfe der NWSIB

Übersicht über drei Fallstudien und Ergebniss

CALIBRATION OF CAR-FOLLOWING MODELS WITH SINGLE- AND MULTI-STEP APPROACHES

Microscopic traffic simulation models are applied in the analysis of transportation systems for years. Nevertheless, calibration (and validation) of microscopic sub-models such as car-following and gap-acceptance models is still a recent matter. The objective of the calibration is to adapt the simulation output to empirical data by adjusting the model's parameters. However, simulation results may vary from the underlying real-world data, despite the calibration. To analyze these deviations the present paper compares two different approaches of calibration using data from a single-lane car-following experiment on a Japanese test track. It is demonstrated that the results of the two methods differ significantly. A recommendation for the more appropriate method to use is given