Marcus Gerstenberger’s scientific contributions

Network management systems (German: Netzbeeinflussungsanlagen - NBA) are one possibility to manage traffic in the road network optimally in accordance with the existing traffic loads and travel times, especially in the event of disturbances in the traffic flow. The methods currently used for impact assessment of NBA based on the guideline “Hinweise zur Wirksamkeitsschätzung und Wirksamkeitsberechnung von Verkehrsbeeinflussungsanlagen” (FGSV Issue 311) calculate the effects on traffic flow using time costs. However, the parameters included in the procedures are empirically difficult to determine and are based on assumptions, especially for the compliance rate and for the travel times on normal and alternative routes. The aim of the research project was to develop an assessment analysis method that supports proof of the traffic effect of NBA in a more transparent and practical way. Based on a literature review of procedures for assessment analysis and control strategies of NBA as well as expert interviews with representatives of the road administration, relevant impact components were identified and their actual options for calculation evaluated. The use cases “traffic disturbance information” (use case S) and “alternative route recommendation” (use case A) for NBA were established in a new analysis method for ex-ante and ex-post investigations because of these findings. Information from Floating Car Data (FCD) is used to assess the relevance of disturbances and the estimation of travel times in undisturbed and disturbed situations, time losses due to the disturbances and resulting time advantages. The transmission of the traffic disturbance information at the decision point (use case S), whether with or without additional recommendation of an alternative route, also has an influence on the behavior of road users. For use case S the number of road users informed about the disturbance is used to assess the effectiveness of an NBA. If, in addition to the traffic disturbance information, an alternative route recommendation is shown, the use case A for the relevant time range is also considered. The procedure in use case A assumes that a recommendation of an alternative route results in time advantages for the road users following the recommendation compared to continuing the drive on the normal route with the disturbance. To assess the traffic impact of NBA for use case A, the sum of these time advantages for all relevant road users in passenger car and truck traffic is used. For this purpose, the characteristics of the network of normal route and alternative route are analysed. From this analysis, indications of the relevance of disturbances on the normal route for use cases S and A can be derived. A further distinction is made between the traffic volume of road users entering the normal route and the traffic volume of those passing through the entire normal route to the end point (usually in an undisturbed situation). Furthermore, information about the number of road users who are switching to the alternative route is required. Additionally, data on disturbances and in the case of ex-post investigations also data on display contents of the NBA are needed as input data. On the alternative route, the network element that has the lowest capacity must be located. With the analysis method, the traffic effects of an NBA can be calculated. In use case A, the time advantages for the influenced road users (passenger cars and trucks) are shown. The benefits of the NBA can be determined based on time advantages using time cost rates. In addition to the procedures for effectiveness analysis, a methodological approach to the strategy definition for NBA is developed, which is based on the same principles as the assessment of traffic disturbances. In the context of an exemplary practical application, it was shown that the processing steps described in the procedure and the necessary data are suitable and the method is usable for an impact assessment of NBA. Finally, recommendations are formulated for the integration of the project results into the FGSV guidelines. In addition, information is given on how to improve the application of the method. Necessary data should be available in standardized data formats and in a continuous data storage. To simplify the application, a software tool should be implemented and the knowledge gained from process applications should be collected in a knowledge repository.

Due to the increasing amount of freight traffic on German motorways there is an increasing demand for parking facilities for trucks at motorways. In addition to the long-term expansion of the capacity of parking facilities, potentials for improving the situation for truck parking are seen in using telematic parking guidance systems. A requirement for such a parking guidance system is an effective and reliable detection of the occupancy of the parking facilities. So far, there is no testing procedure for systems for the area-wide detection of parking occupancy uniformly and in a comparable manner. For this purpose, functional criteria for a detection system with areawide detection have been compiled in the working group “Lkw-PLS” consisting of representatives of national and federal road authorities. As part of the Research and Development project “Scientific monitoring of the digital test field on the A 9 between Munich and Nuremberg”, a uniform procedure for functional and suitability testing of these criteria was developed at the Federal Test Field PWC Gelbelsee-West. This testing procedure shall be used as a basis for future tenders for parking detection systems on parking facilities at motorways. The procedure has been subjected to a practical test and has been released for use in official testing.

This paper presents a methodology to forecast the changes of NO2 immissions due to changes in fleet composition of passenger vehicles and emission classes. Within this scope, possible changes in vehicle technologies (e.g. lower emission of diesel engines) are considered in different scenarios using the example of Munich. In line with this purpose, the traffic volumes and origin-destination data are obtained from a macroscopic traffic model, local registration statistics of vehicles are used to estimate fleet compositions. In addition, for immission modelling data on characteristic roadside structure as well as weather conditions of the investigation area are considered. For different scenarios with adapted passenger vehicle fleet compositions, the reductions of NO2 immissions levels as well as the special distribution in the road network is calculated. Additionally, the remaining length of the road network, where the legal threshold of daily average of 40 µg/m³ NO2 in Germany is exceeded, is shown for each scenario. Moreover, the contribution of the sub-fleet of commercial cars to these changes in emission is calculated. The results show that the higher share of low emission classes (e.g. Euro 6 RDE for diesel engines) lead to continues reductions of NO2 immissions. The highest decrease of NO2 immission in the main road network of Munich is calculated for use of petrol cars with emission class Euro 6 for all passenger vehicles. To achieve the goal that the predominant part of the road network is fulfilling the legal threshold for NO2 immissions, a high share of electric vehicles is needed.