Keynote speech on the "9-Euro-Ticket" and its utility for of low-income people in Hamburg and surroundings. The "9-Euro-Ticket" allowed passengers to ride public transport in the whole of Germany from June to August 2022 for a monthly fee of 9 EUR. Outlook for the "Deutschlandticket", which is to be offered from spring 2023 and is to be valid throughout Germany.

PURPOSE In berth allocation planning, container vessels are to be assigned to berthing locations and times at the quay of a container terminal. Terminal operators often aim to provide the best possible service quality to the shipping companies, i.e. especially short waiting times. However, the actual arrival times of vessels are uncertain due to external influences, which impedes the planning and may lead to conflicts with respect to scheduled berths. METHODOLOGY Machine Learning techniques are applied to enable the determination of patterns in AIS data and hence to develop forecasts of the ships’ arrival times. With a robust optimization approach based on Dynamic Time Buffers, uncertainty is proactively considered in the planning phase, resulting in more robust berthing schedules. FINDINGS The results of this new approach are evaluated from an ex post perspective using real ship data and actual ship arrival times. It is shown by a numerical study that the average number of conflicts can be reduced significantly by this approach and that the new concept improves the schedules’ robustness. ORIGINALITY A novel concept of Dynamic Time Buffers is presented where the assigned buffer time depends on the level of uncertainty in the vessel’s arrival time and which leads to improved berthing plans.

Climate change and the ever increasing rate of urbanization are amongst the main causes of the growing impacts of floods on humans, animals and plants. The reduction of green areas in cities and the uneven distribution of precipitation have resulted in an increase in the number of flood events which exceed the capacities of drainage systems. Once the capacity of the designed system is exceeded, an uncontrolled overland flow occurs putting at risk whatever lies in its path. To reduce this uncontrolled flow a omprehensive plan for the management of rainwater in urban areas is required. In order to achieve this objective it is necessary 1 to promote infiltration of rainwater as close to the source as possible, and 2 to control the surface runoff. This is known as source and pathway control. Although in recent years detention structures and infiltration techniques have been regarded as promising measures of sustainable drainage systems, very little is known about measures to deal with the exceeding flow. In the present work, new possibilities for managing the rainwater in public areas will be investigated with particular focus on systems for the conveyance and temporary storage of the exceeding water for example in multifunctional spaces. A theoretical concept to define and to model this new approach will be developed to assess the potential of exceeding flow conveyance and storage systems as part of an urban rainwater management plan. This approach and study results of this work will be presented for the Wandse catchment in Hamburg for land use and climate change scenarios for 2050 in the scope of KLIMZUG-NORD project.

The energy system transformation towards decentralized and renewable energy resources (DERs) is inevitable in order to mitigate climate change. New operational concepts arise as a consequence of structural system changes and the ongoing digitization of energy systems. Research in the field of transactive energy gives increasing importance to energy markets, not only from an economic perspective, but also as part of an approach for efficiently and resiliently operating grids. Aggregators help to bring the DERs’ potential for flexibility to the market. However, an aggregator’s decision on how to employ a large number of different kinds of flexible resources, considering the respective technological properties and also economic conditions of the flexibility providers, is a complex problem. In this work, mixed-integer linear programming is used to develop and implement an optimization model for this problem. The model is applied in a case study consisting of a distribution grid with a large number of prosumer households with load and generation profiles and individual flexible assets. The new research contribution lies in the high level of detail and the combined consideration of different flexibility types such as heat pumps, electric vehicles, battery storages and time-shiftable loads. The integration of a flexibility framework which regulates the aggregators’ degrees of freedom in deploying their customers’ flexibility is a further innovation compared to existing literature. The numerical results from the case study give insights regarding the utility that the different types of flexibility provide to the aggregator, to the households and to the overall grid resilience. Further analyses validate the efficiency of the flexibility framework.

In this presentation, having been held on the occasion of the 72nd plenary assembly of departments of civil engineering, geodesy and environmental engineering (FTBGU), three questions are addressed: Why should active learning become an integral part of teaching concepts in technical sciences? Why should research-based learning be fostered alike? How can both approaches contribute to better learning results? As Freeman et al. (2014) point out with respect to their comprehensive meta study on active learning in engineering, failure rates in large-scale classes decrease significantly when teachers make use of methods to activate students in class. It is therefore not surprising that active learning is associated with central aspects of modern teaching and learning, often summed up by the generic concept „shift from teaching to learning” (Barr & Tagg, 1995): Instead of comprehensively covering the subject content by speaking out every detail by themselves during their lectures, which is still very common in STEM study programs, university teachers rather act as expert advisors or commentators to guide and inspire student learning activity, making use of educational methods like think-pair-share, peer instruction or variations of the innovation debate-format. For this, the teaching innovation project „hydrology” (part of 3rd semester curriculum of the bachelor program “civil and environmental engineering” at Hamburg University of Technology) can serve as good practice: A lecture was replaced by a series of expert presentations run by student groups, each and every session being complemented by student-driven panel discussions and additional peer feedback. What is more, active learning in university teaching can serve as a starting point to transform teaching concepts according to research-based learning. For many reasons, this educational format should be considered when it comes to the renewal of course or curriculum design. For example, institutions of higher education are obligated to enable their students to do a doctoral thesis by successfully fulfilling preceding master programs. Therefore, research-based learning can be applied to different phases of a study program and to various levels of difficulty. As a small-scale variation, it can be carried out as limited discussions on research theses or methodical questions, embedded within common lectures. On a large scale, this approach can also be implemented by long-term research projects carried out independently by students and being an integral part of the curriculum. At Hamburg University of Technology, 60 international students carry out a range of group-based research projects in environmental engineering within the module “water & wastewater systems” (Institute of Wastewater Management and Water Protection). In addition to the project work, scientific conversations take place in an idea workshop where students give milestone presentations and get peer feedback with respect to their work process status. The teaching concept also comprises a blog and a closing conference.

The range of battery electric vehicles (BEV) remains one of the central barriers against the adoption of the technology. Potential users often fear the relatively low range - compared to internal combustion engine vehicles (ICEV) - to limit the personal mobility behavior. This phenomenon is often referred to as “range anxiety” (Krishna 2021; Pevec et al., 2020). Additionally, the performance of BEV under varying conditions, such as winter temperatures, is perceived as unstable, which leads to a lack of trust (Krishna, 2021; Buhmann, 2023). The current WLTP (Worldwide Harmonized Light-Duty Vehicles Test Procedure) standard to calculate a vehicle’s range is measured in a test box at +23°C (European Union, 2018) and can therefore not serve as reference for the performance in winter or low-temperature periods. Still, buyers use the WLTP value as their main guidance and are disappointed when the BEV fails to meet expectations. Recent media coverage of the example on Tesla Inc. claimed that complaints on the range were the number one issue adopters have, which urged the company to install a service unit solely focused on suppressing such complaints (Stecklow, 2023). Another example is South Korea's antitrust regulator imposing a 2.2 billion dollars fine on Tesla Inc. for misleading promises of their vehicle's range under low temperatures (Reuters, 2023). This study aims to investigate the relation of actual BEV ranges to the ambient temperature and summer and winter seasons, as well as to the range given in the vehicle specifications. The findings seek to contribute to the understanding of BEV performances under real conditions. The underlying data set is one of the largest currently existing, consisting of 159 BEV and 5 different models which were used during the “Hamburg – Wirtschaft am Strom” project within three years by real companies. The results show the correlation between changes in BEV range and ambient temperatures as well as their significance. The study suggests an innovative approach for adjusting the WLTP. With regard to seasonal local conditions and the observed optimal operating point for BEV, meaningful range values for customers could be established.

Ein Vortrag und Diskussion zu notwendigen Maßnahmen resultierend aus dem automatisierten und fahrerlosen Fahren im ÖPNV mit Schwerpunkt Haltestellen im ländlichen Raum

Dynamic environmental conditions in industrial bioprocesses can lead to formation of population heterogeneities and thuslowered productivities. Since this phenomenon is poorly understood, an integrativeapproach of experimental exploitation andtheoretical prediction might improve comprehension. Population heterogeneity in L-phenylalanine production is experimentally studied in a fed-batch process with anEscherichia coliquadruple reporter strain.Industrial bioprocess conditions are simulated in a novel two-compartment setupcoupling a stirred-tank bioreactor to acoiled flow inverter as bypass. Fluorescence of the reporter strain revealed differences in single-cell physiology for homogeneous and dynamic cultivation conditions. The experimental data is further integrated into a theoretical description of aheterogeneous population. A coarse-grained approach is established with strictmass conservation for bacterial growthduring the fed-batch process. This iscoupled with an environmental model characterizing the bioprocess dynamics tocapture the interaction between the cellpopulation and the bioreactor.