City Of Berlin Research Articles

Explorative analysis of potential MaaS customers: an agent-based scenario

Abstract Mobility-as-a-Service (MaaS) is a user-centered service that combines different mobility services offered to the users by means of different packages. The users fulfil their daily mobility needs using a subscription-based smartphone application, which gives them access to the services within their mobility budget. Various surveys on MaaS have been run in the last years to capture which transport mode can be more suitable within a package and the user’s willingness to pay. Moreover, pilot projects have been employed to figure out potential MaaS users’ characteristics and inclination. Results among stated preference scenarios differ due to the different characteristics of the demand and supply. Hence, there is not a general consensus around the potential of MaaS membership choice. This study embraces an agent-based modeling approach which allows to maximize the user’s utility of performing activities and account for travel costs to simulate two scenarios. The first one considers carsharing systems and public transport as a basic MaaS package. We further employ an economic approach which assumes MaaS services costs to be perceived as fixed costs by the customers. We assume the same MaaS package to be accessible to the generated population of the city of Berlin. The second is a Pay-as-you-go (NoMaaS) scenario where users pay the service experiencing trip-based costs. Evaluating the differential of users’ utility when comparing the two scenarios this study aims to explore the characteristics of the potential MaaS customers. The results indicate a higher propension to subscribe among public transport and two-way car-sharers, whereas MaaS seems to capture new free-floating customers. The potential users employ both carsharing services longer in their daily trip chain in the MaaS scenario, because the new mobility system allows users to do not consider marginal cost in their daily travel pattern. Outcomes also indicate that MaaS will not be a direct substitute to private car, and it’s likely to extend rental time of car sharing systems.

(Non)curating the Creative City: From 100 Grad to Performing Arts Festival Berlin

The independent performing arts in Berlin, counterpart to the established city and state theatre system, have undergone fundamental change over the last decades. As part of this change, the 100 Grad Festival, a crucial event for the scene for over twelve years, ended in 2015 and was replaced by the Performing Arts Festival (PAF), which addresses the city of Berlin as a whole. This paper will trace the institutional transition from 100 Grad to PAF by highlighting organizational continuity and differences, and by analyzing the discourse accompanying the shift in the field of Berlin’s independent performing arts. The point of departure for the paper are questions of curation, which both festivals reject, yet re-employ in different strategies, especially towards emergent artists. However, contextualizing the festivals within broader tendencies in city development – the governmentality of the ‘creative city’– shows that opposing strategies may equally fall in line with aesthetic capitalism, leading to a paradoxical outcome.

Assessing Two-way and One-way Carsharing: an Agent-Based Simulation Approach

Carsharing companies can customize their service by adopting different pricing schemes and offers with the aim of increasing fleet use and profits. Different business models have been developed such as round-trip and one-way. It is clear that, even though many aspects of the business model and operations are the same, the different way in which these services are supplied leads to a diverse response from the users. In this work, we analyze how a fixed pricing scheme affects the behavior of the members of two different carsharing systems: two-way and one-way, explicitly considering their different income distributions to analyze social equity aspects. The dynamic pricing policy is simulated in MATSim, an agent-based simulator able to generate realistic mode choices based on individual activity-travel behavior. Scenarios with a synthetic population of carsharing members for the city of Berlin are analyzed. We aim to provide an experimental analysis that addresses the different behavior of different demand sectors, categorized by income, in function of the supply distributed on the territory. Simulation results show that the two services are not in competition between each other: the two-way service is used as a substitute for private cars while the one-way system is preferred from agents who choose to use multiple types of modes during the day. The response from the different income classes tends to be similar for both services since all the users within the same purchase power have the same degree of acceptance for both systems.

(Non)curating the Creative City: From 100 Grad to Performing Arts Festival Berlin

The independent performing arts in Berlin, counterpart to the established city and state theatre system, have undergone fundamental change over the last decades. As part of this change, the 100 Grad Festival, a crucial event for the scene for over twelve years, ended in 2015 and was replaced by the Performing Arts Festival (PAF), which addresses the city of Berlin as a whole. This paper will trace the institutional transition from 100 Grad to PAF by highlighting organizational continuity and differences, and by analyzing the discourse accompanying the shift in the field of Berlin’s independent performing arts. The point of departure for the paper are questions of curation, which both festivals reject, yet re-employ in different strategies, especially towards emergent artists. However, contextualizing the festivals within broader tendencies in city development – the governmentality of the ‘creative city’ – shows that opposing strategies may equally fall in line with aesthetic capitalism, leading to a paradoxical outcome.

Address-based computation of intra-cell distances for travel demand models

Abstract Intra-cell travel is a difficult topic in zone-based travel demand models. In the past, different strategies were applied to approximate the average intra-cell distances by using zone size, diameter, distances to neighbors and other techniques. In this work we examine a new approach which uses address coordinates and a high performance routing program to achieve more accurate results. We apply our method to three different zoning schemes for the city of Berlin, Germany. The result consists of average travel distances for each zone based on all potential destinations. Surprisingly, the ratio of network distance and beeline distance is independent from the three different zoning schemes tested. This detour-factors depend only on the street network. For beeline distances larger than 400 m, we identify a simple transfer function between beeline and travel distance, which extends the classic transfer functions between different zones to intra-zone distances. We show that many distances below 100 m belong to a second class of intra-cell routes, which corresponds to the routing in a Manhattan-block grid. These two classes describe the intra-cell distances in our example quite well and we expect this approach to be helpful to examine other areas.

Unexpected Gene-Flow in Urban Environments: The Example of the European Hedgehog.

Simple SummaryAn urban environment holds many barriers for mammals with limited mobility such as hedgehogs. These barriers appear often unsurmountable (e.g., rivers, highways, fences) and thus hinder contact between hedgehogs, leading to genetic isolation. In our study we tested whether these barriers affect the hedgehog population of urban Berlin, Germany. As Berlin has many of these barriers, we were expecting a strong genetic differentiation among hedgehog populations. However, when we looked at unrelated individuals, we did not see genetic differentiation among populations. The latter was only detected when we included related individuals too, a ‘family clan’ structure that is referred to as gamodemes. We conclude that the high percentage of greenery in Berlin provides sufficient habitat for hedgehogs to maintain connectivity across the city.We use the European hedgehog (Erinaceus europaeus), a mammal with limited mobility, as a model species to study whether the structural matrix of the urban environment has an influence on population genetic structure of such species in the city of Berlin (Germany). Using ten established microsatellite loci we genotyped 143 hedgehogs from numerous sites throughout Berlin. Inclusion of all individuals in the cluster analysis yielded three genetic clusters, likely reflecting spatial associations of kin (larger family groups, known as gamodemes). To examine the potential bias in the cluster analysis caused by closely related individuals, we determined all pairwise relationships and excluded close relatives before repeating the cluster analysis. For this data subset (N = 65) both clustering algorithms applied (Structure, Baps) indicated the presence of a single genetic cluster. These results suggest that the high proportion of green patches in the city of Berlin provides numerous steppingstone habitats potentially linking local subpopulations. Alternatively, translocation of individuals across the city by hedgehog rescue facilities may also explain the existence of only a single cluster. We therefore propose that information about management activities such as releases by animal rescue centres should include location data (as exactly as possible) regarding both the collection and the release site, which can then be used in population genetic studies.

Assessment of the regionalised demand response potential in Germany using an open source tool and dataset

With the expansion of renewable energies in Germany, imminent grid congestion events occur more often. One approach for avoiding curtailment of renewable energies is to cover excess feed-in by demand response. As curtailment is often a local phenomenon, in this work we determine the regional demand response potential for the 401 German administrative districts with a temporal resolution of 15 min, including technical, socio-technical and economic restrictions. Our analysis yields that power-to-heat technologies provide the highest potentials, followed by residential appliances, commercial and industrial loads. For the considered 2030 scenario, power-to-gas and e-mobility also contribute a significant potential. The median value of the cumulated load increase potential of all technologies is 25MW per administrative district. Using such a load increase potential to cover regional excess feed-in would suffice to avoid the curtailment of 8 classical wind turbines. Further, we calculated load shifting cost-potential curves for each district. Industrial processes and power-to-heat in district heating have the lowest load shifting investment cost, due to the largest installed capacities per facility. We distinguished between different size classes of the installed capacity of heat pumps, yielding 23% lower average investment cost for heat pump flexibilisation in the city of Berlin compared to a rural district. The variable costs of most considered load shifting technologies remain under the average compensation costs for curtailment of renewable energies of 110 € /MWh. As all results and the developed code are published under open source licenses, they can be used to integrate load shifting dispatch into energy system models.

Urban Hedgehog Behavioural Responses to Temporary Habitat Disturbance versus Permanent Fragmentation.

Simple SummaryWildlife is exposed to environmental disturbances. Some are limited to a short period and pass by, others are of a permanent nature. Often these two kinds of disturbances occur simultaneously. This makes it difficult to disentangle the specific behavioural response to each disturbance. As species may respond to different disturbances in different ways, it is important to know the species-specific and disturbance-specific responses to develop effective species conservation action. We investigated the behavioural responses of European hedgehogs (Erinaceus europaeus) in Berlin to temporary disturbance (in the form of an open-air music festival) and permanent disturbance (in the form of habitat fragmentation). We show that a music festival is a major stressor that strongly influences all investigated behaviours. Urban hedgehogs in a highly fragmented area showed subtle behavioural changes compared to those in low-fragmented areas, suggesting that fragmentation was a moderate challenge which they could cope with. Thus, the temporary disturbance by a music festival had a more serious impact on hedgehog behaviour than permanent disturbance caused by fragmentation. Moreover, we show that males responded stronger to the transient disturbance and females responded stronger to habitat fragmentation.Anthropogenic activities can result in both transient and permanent changes in the environment. We studied spatial and temporal behavioural responses of European hedgehogs (Erinaceus europaeus) to a transient (open-air music festival) and a permanent (highly fragmented area) disturbance in the city of Berlin, Germany. Activity, foraging and movement patterns were observed in two distinct areas in 2016 and 2017 using a “Before & After“ and “Control & Impact“ study design. Confronted with a music festival, hedgehogs substantially changed their movement behaviour and nesting patterns and decreased the rhythmic synchronization (DFC) of their activity patterns with the environment. These findings suggest that a music festival is a substantial stressor influencing the trade-off between foraging and risk avoidance. Hedgehogs in a highly fragmented area used larger home ranges and moved faster than in low-fragmented and low-disturbed areas. They also showed behaviours and high DFCs similar to individuals in low-fragmented, low disturbed environment, suggesting that fragmentation posed a moderate challenge which they could accommodate. The acute but transient disturbance of a music festival, therefore, had more substantial and severe behavioural effects than the permanent disturbance through fragmentation. Our results are relevant for the welfare and conservation measure of urban wildlife and highlight the importance of allowing wildlife to avoid urban music festivals by facilitating avoidance behaviours.

On the combination of water emergency wells and mobile treatment systems: a case study of the city of Berlin

A shortage of water leads to severe consequences for populations. Recent examples like the ongoing water shortage in Kapstadt or in Gloucestershire in 2007 highlight both the challenges authorities face to restore the water supply and the importance of installing efficient preparedness measures and plans. This study develops a proactive planning approach of emergency measures for possible impairments of water supply systems and validates this with a case study on water contamination in the city of Berlin. We formulate a capacitated maximal covering problem as a mixed-integer optimization model where we combine existing emergency infrastructure with the deployment of mobile water treatment systems. The model selects locations for mobile water treatment systems to maximize the public water supply within defined constraints. With the extension to a multi-objective decision making model, possible trade-offs between the water supply coverage and costs, and between the coverage of differently prioritized demand points are investigated. Therefore, decision makers benefit from a significantly increased transparency regarding potential outcomes of their decisions, leading to improved decisions before and during a crisis.

Real-world insights on public charging demand and infrastructure use from electric vehicles

The city of Berlin has significantly expanded public charging infrastructure for electric vehicles. As a result of this investment, real-world charging data for the city of Berlin are available for the first time. In addition to other metrics, this dataset contains specific information about carsharing vehicles. This research letter offers numerous insights into public charging demand and infrastructure. The results are only now available due to a sufficient fleet size of electric vehicles.The analysis shows that the distribution of charging stations is very unequal in Berlin. The data also show that the infrastructure network is much denser in the city center. While there is an unequal distribution of infrastructure, we see that the utilization of infrastructure is relatively equal. This reflects unequal charging demand, as can be expected based on the location of the infrastructure. We also determine that the majority of public charging events come from free-floating carsharing vehicles. The analysis of infrastructure use shows that the edge of the city center has the highest rates of stations occupied by vehicles after completing charging. Carsharing users occupy infrastructure after charging significantly more than individual private and commercial users. However, if the pricing scheme allows, individual users also occupy infrastructure after completing charging.The research letter provides several policy recommendations for the build-up and operation of charging infrastructure. These focus on charging demand from individual users, infrastructure efficiency, and carsharing operators and their business models. The results are timely as decisions on public charging infrastructure must be made now to meet electric vehicle demand.

Visualizing crash data patterns

This paper demonstrates an approach that makes it easy to find patterns in traffic crash data-bases, and to specify their statistical significance. The detected patterns might help to prevent traffic crashes from happening, since they may be used to tailor campaigns to the community at hand. Unfortunately, the approach described here comes at a cost: it identifies a considerable amount of patterns, not all of them are being useful. The second disadvantage is that is needs a certain size of the data-base: here it has been applied to a data-base of the city of Berlin that contains about 1.6 Million (M) crashes from the years 2001 to 2016, of which about 0.9M had been used in the analysis.

Still in the shadow of the wall? The case of the Berlin biotechnology cluster

The evolution of knowledge networks has recently received a lot of attention from researchers. Empirical studies have shown that different types of proximities and network structural properties play a decisive role in tie formation. The present paper contributes to this literature by arguing that while these are crucial, they do not capture the full range of localities’ influence on the evolution of knowledge networks. We support our argument with an empirical study on the development of the biotechnology knowledge network of Berlin from the early 1990s till 2016. The network was created by combining data on co-patenting, co-authorship and joint R&D projects. Forces driving the evolution of the network were identified with separable temporal exponential random graph models (STERGM). In addition to the ‘usual suspects’ (main proximity dimensions and structural factors), we found that the network is still developing in the ‘shadow of the wall’. The different social contexts in the different parts of the city of Berlin still hamper the establishment of collaborative ties between the former East and the former West Germany even 30 years after reunification.

Zooming Into the Ecosystem: Agency and Politics Around Open Data Platforms in Lyon and Berlin

Open data platforms provide free access to datasets in key areas of urban development. Often provided by the local state, open data platforms constitute a part of smart city strategies worldwide, serving different, potentially contradictory aims, i.e. fostering economic development, enhancing transparency of urban governance and reshaping the relation between citizens and the state. While benefits of open data are often highlighted, recent research has pointed out to open data initiatives failing to account for and include the ecosystem of urban actors and their interests. Instead, open data platforms are embedded in complex networks of actors and institutions, and consequently form both an object and an instrument of urban governance. Our interest lies in understanding how open data platforms are coproduced by different actors based on their conception of open data. Thus, we theorise the development of open data initiatives through a dynamic approach to agency focussing on the strategies of different actor groups shaping open data initiatives and platforms, in specific governance contexts that define barriers and windows of opportunity. Empirically, our paper will analyse the development and governance of open data initiatives and platforms in the cities of Lyon and Berlin. Departing from the initial steps for setting open data on the agenda, we will provide a process-based perspective unpacking actor strategies and agency to shape open data policies, concrete initiatives and platform design. The analysis is based on tracing the development processes and on interviews with representatives of the administration, open data initiatives and civil society. Our analysis identified a narrowing down of open data initiatives to objectives of economic development and efficient administration, despite the existence of broader visions on open data among other actors. This can be traced back to the impact of shifts in the urban governance contexts and high salience of personnel, financial and technical resources for defining the dominant conception of open data.

Suspension: disabling the city of refuge?

ABSTRACT This article focuses on suspension: a process and a politics in migration governance that disables subjects and destabilises the state. Drawing on migrant, civic actor and policy-maker insights and experiences in the cities of Athens, Berlin and London, the discussion reveals how suspension is operationalised and enacted. As recorded across three cities, suspension has become a way to govern migration as an unequal and racialised system by obscuring, prolonging and deferring state responsibilities and migrants’ access to resources and rights. By focusing on who is most likely to be suspended, and how the urban convenes both everyday bordering and new solidarities, we aim to understand the politics of migration in a volatile political and economic conjuncture. Invoking the city of refuge as an actually existing but fragile ethico-political project, we critically reflect on the currency of urban politics of sanctuary cities as redemptive spaces detached from the punitive functioning of the state. We explore how suspension is operationalised in the city through three core processes: the fracturing of legalities; the devolution of care; and the spatialising of uncertainty. We further reflect on the precarious practices care and solidarity which engage our shared humanity as opposed to enforced differences.

Carbon Pools of Berlin, Germany: Organic Carbon in Soils and Aboveground in Trees

The emission of climate-relevant gases, especially carbon dioxide, is often associated with urban areas. However, cities have accumulated organic carbon in their soils and vegetation over centuries and offer important ecosystem services for the city through carbon storage. The aim of this study is to estimate the total carbon storage of the central European city of Berlin by combining the organic carbon (Corg) stored in soils and the carbon found in aboveground biomass. We used 432 soil samples that were taken across 18 different land uses in order to estimate the carbon content for each land use based on the laboratory findings of each sample. This large amount of data, which is excellent for such a study, provides an important basis for the evaluation and analysis of the carbon storage potential. Taking into account the degree of soil sealing, the carbon calculations for each individual land use were then transferred to the total area of Berlin in order to produce a spatially explicit carbon map. Soil carbon stocks are reported as units of carbon either as kg/m² or in t/ha for each block. The carbon storage was estimated for both topsoil and subsoil. In addition, we estimated the carbon stored in 596,975 street trees and park trees according to the biomass equations for each tree species. The results show that more than two-thirds of the carbon present is accounted for by soils, which makes them the largest carbon reservoir of the city. Park trees store the most carbon in urban trees apart from urban forest trees. The total carbon stock of Berlin was estimated to be 24,087,344 tons, which corresponds to an approximate quantity of 270 t/ha. The distribution of carbon storage across the city shows the highest values towards the city boundaries. This holds true for the soil as well as the vegetation. The greatest quantities of total carbon are stored in the subsoils of the city’s suburbs. This study is the first of its kind to combine the carbon stocks of the soil and the vegetation in a city in order to estimate its carbon storage potential. It provides detailed soil carbon maps and biomass estimations, which can contribute to carbon storage investigations in other cities with similar climatic and ecological conditions.

The Voices of Berlin: Busking in a ‘Creative’ City

The city of Berlin is often advertised as one of the most prominent creative cities today. In the past two decades, its marketing agencies have constructed a carefully crafted urban image designed to attract the young, mobile and creative workers that move the contemporary economy. To do that, they rely on cultural temporary uses that enable selected urban spaces to have the desired ‘cool’ and authentic ambiance that distinguishes this city from others within the competitive global network. This paper investigates the phenomenon of abundant street performers in the German capital to find out if and how these artists perceive their role and instrumentalisation within these creative policies. The field research carried out through the method of ethnography reveals that their understanding of their art as small resistances in urban space often clashes with their use in broader placemaking schemes that have negative consequences. The article begins with a discussion of creative policies in Berlin from an Urban Planning point of view, highlighting how it encourages the migration of young artists and creative professionals. It then analyses the definitions of busking in the existing literature in the Social Sciences to understand its potential as a builder of sociability. Moreover, it draws on theories that speak of the “looseness” of space and the idea of tactically appropriating a place through art to build an interdisciplinary approach between the different fields. Lastly, it presents the case study, using the performers’ own testimonials to draw conclusions about the temporary uses of urban space within a broader urban context.

A parental school choice misery: Middle class parents’ dilemma in choosing a primary school in Berlin’s multi-ethnic neighborhoods

Abstract To follow up on research conducted in several countries, in this paper, we look at the dilemmas middle-class parents face of being “good parents” by choosing the “best” school with a milieu-related environment for their child versus being “good citizens” by choosing a “local” public school with a large proportion of students from a working-class or migrant background. Analyzing semi-structured interviews with parents, the paper explores whether and how parents in Germany’s capital city of Berlin refer to this dilemma concerning primary school choice and how they resolve it and justify their decision. The parents interviewed applied strategies in deciding to be “good parents” or “good citizens” or at least to make it easier to solve the dilemma. All the strategies presented in other studies can be found in our sample as well. In addition, we identified two more parental strategies: the strategy of downward comparison and the strategy of choosing a private school. It is notable that the perceived proportion of children with a migrant background in the neighborhood played a major role in relation to the dilemma and the strategies chosen.

A dynamic analysis of a SAGSHP system coupled to solar thermal collectors and photovoltaic-thermal panels under different climate conditions

The use of multi-source energy systems is a promising technical solution for the reduction of greenhouse gases emissions and, at the meantime, for enhancing the exploitation of renewable energy sources.The present paper analyses a Solar Assisted Ground Source Heat Pump system and tries to fill the gap in the literature, where a direct comparison between the consolidated solar thermal technology and the emerging and widely discussed photovoltaic thermal technology is missing. Indeed, the two different devices for the exploitation of solar energy have been analysed through dynamic simulations carried out in TRNSYS environment. Through this approach, it is possible to investigate and predict in detail the thermal and electrical behaviour of the energy system, composed by a water-to-water heat pump, which withdraws from two thermal reservoirs that are connected to a solar loop, composed either of solar thermal collectors or of photovoltaic thermal panels and to a ground loop.The heat pump is used to provide space cooling and space heating to a residential building, through fan coil terminal units or radiant floor system. Furthermore, the heat pump system assists the solar field in the production of domestic hot water.This study looks at the development of a flexible system able to work in different operating conditions. The model’s boundary conditions can be changed for simulating a variety of case studies as the weather condition, the building load and the domestic hot water profile can be easily changed, together with specific components’ parameters. The control strategy makes it possible to vary the setpoint temperatures for simulating different operating conditions and management choices. In this way, the user can easily adapt the model functions to a specific plant system.The operating conditions of the two systems layouts have been compared and the energy performances evaluated for three case studies characterised by the weather conditions of the European cities of Berlin (mild-cold climate), Venice (mild climate) and Barcelona (mild-warm climate), and the corresponding thermal load profile of a two-storey building with a useful floor area of 170 m2.The study shows the possibility to directly exploit the solar energy for the domestic hot water production and as a heat source for the heat pump. The results from the comparison between the two systems’ configurations, with photovoltaic thermal panels and with solar thermal collectors, prove that there is the possibility to obtain a relevant improvement in the efficiency of the heat pump using photovoltaic thermal panels. The investigated multi-source energy system, moreover, allows an optimal employment of the available renewable heat sources and could easily be applied to case studies characterized by different boundary conditions.

How emergency departments prepare for virus disease outbreaks like COVID-19.

How emergency departments prepare for virus disease outbreaks like COVID-19.

The COST IRACON Geometry-Based Stochastic Channel Model for Vehicle-to-Vehicle Communication in Intersections

Vehicle-to-vehicle (V2V) wireless communications can improve traffic safety at road intersections and enable congestion avoidance. However, detailed knowledge about the wireless propagation channel is needed for the development and realistic assessment of V2V communication systems. We present a novel geometry-based stochastic MIMO channel model with support for frequencies in the band of 5.2–6.2 GHz. The model is based on extensive high-resolution measurements at different road intersections in the city of Berlin, Germany. We extend existing models, by including the effects of various obstructions, higher order interactions, and by introducing an angular gain function for the scatterers. Scatterer locations have been identified and mapped to measured multi-path trajectories using a measurement-based ray tracing method and a subsequent RANSAC algorithm. The developed model is parameterized, and using the measured propagation paths that have been mapped to scatterer locations, model parameters are estimated. The time variant power fading of individual multi-path components is found to be best modeled by a Gamma process with an exponential autocorrelation. The path coherence distance is estimated to be in the range of 0–2 m. The model is also validated against measurement data, showing that the developed model accurately captures the behavior of the measured channel gain, Doppler spread, and delay spread. This is also the case for intersections that have not been used when estimating model parameters.