Highway Capacity Estimation: International Regulation and Neurostructural Remodeling Approach

Increasing number of personal vehicles and cargo transportation requires the development of a well-planned transport policy within states and states associations. The existing normative acts give different directions in the field of regulation of transportation processes. One of the most important aspects in assessing the existing state transport arteries and planning new ones is the analysis of their capacity, which could be performed in various ways. The classical approach defines capacity as a certain value that is constant for the entire period under consideration. However, this value is changing at any given point in time depending on various factors (weather, psychological, accidental), and this fact determines the stochastic nature of this indicator. The paper presents an overview of existing approaches and a perspective approach that defines capacity as a random variable. The paper also presents the method to model highway capacity, which delivers greater accuracy compared to traditional approaches used in Russia and Germany. Using the proposed approach it is possible to obtain adequate values of highway capacity, which is important in assessing the quality of the functioning of existing highways and planning new ones

Polluter group specific emission optimisation for regional air quality analyses using four-dimensional variational data assimilation

Pollutants in the atmosphere, such as nitrogen oxides and particulate matter, pose a threat to the environment and human health. In addition to natural sources, anthropogenic emissions contribute significantly to air pollution. Since emission rates cannot be measured directly, their estimates provided by research institutes and national environmental agencies are subject to considerable uncertainty. However, for accurate air quality forecasts using atmospheric chemical transport models such as the regional European Air pollution Dispersion - Inverse Model (EURAD-IM), reliable emission data are crucial. To correct the emission data of inventories based on observations of trace gas and aerosol concentrations in the atmosphere, the EURAD-IM comprises a four dimensional variational data assimilation system (4D-Var) that allows for simultaneous optimisation of initial concentrations and species-dependent emission corrections. In order to improve the knowledge about the sources of air pollution, in this work, a new approach is developed and implemented in the data assimilation system of the EURAD-IM to correct emissions individually for source categories such as road transport, industry and agriculture. For the distinction between the emissions of different source categories, the new approach exploits the spatial separation of emission sources of different categories as well as their characteristic diurnal emission profiles and chemical compositions. Assuming a fixed chemical composition of the emissions of the source categories within the grid cells, a full correlation between the emission corrections of the different chemical species is introduced. Furthermore, an anisotropic diffusion operator is implemented that increases the spatial correlation between the road traffic emission corrections of the grid cells along roads. To investigate the ability of the new development to distinguish between emissions of different sectors, two different types of simulations are performed. In identical twin experiments based on synthetic observations, scenarios with increased industrial and agricultural emissions and a simultaneous decrease in road transport emissions are simulated. The data assimilation system based on the new approach is able to reproduce the emission changes in the experiments for large parts of the model domain through the determined sector specific emission corrections. Furthermore, a study is performed in which the emissions within a two-week period in North Rhine-Westphalia are analysed using real observation data. It is shown that in this scenario a distinction of industrial and power plant emissions versus road transport emissions is possible through the sector specific emission optimisation. Moreover, changes in agricultural emissions can be specified due to their high NH3 fraction. For all observed species, i.e. O3, NO2, SO2, PM10 and PM2.5, the agreement of the simulated with the observed concentrations is comparable to that of a reference simulation using the current EURAD-IM data assimilation system. An improvement of the results is expected through additional observation data, especially of CO and CO2 concentrations

Response functions as a new concept to study local dynamics in traffic networks

Vehicle velocities in neighbouring road sections are correlated with memory effects. We explore the response of the velocities in the sequence of sections to a congestion in a given section and its dynamic characteristics. To this end, we transfer the concept of response functions from previous applications in finance to traffic systems. The dynamical characteristics are of particular interest. We identify two phases, a phase of transient response and a phase of long-term response. The transient response is pronounced when considering the backward propagation of heavy congestions but almost vanishes for forward propagation. For each response phase, we find a linear relation between the velocity response and the congestion correlator, implying that the correlation of congestion is most likely the cause for the velocity response. We also construct a susceptible-decelerated-withdrawing model mathematically inspired by the susceptible-infectious-recovered (SIR) model in epidemiology to describe the transient response. We find that the heavy congestion on a section propagates forward and backward at a similar rate, but the forward sections are more likely to recover from the effect of heavy congestion than the backward sections

On Cells and Agents : Geosimulation of Urban Sprawl in Western Germany by Integrating Spatial and Non-Spatial Dynamics

Urban sprawl is one of the most challenging land-use and land-cover changes in Germany implicating numerous consequences for the anthropogenic and geobiophysical spheres. While the population and job growth rates of most urban areas stagnate or even decrease, the morphological growth of cities is ubiquitous. Against this backdrop, the quantitative and qualitative modeling of urban dynamics proves to be of central importance. Geosimulation models like cellular automata (CA) and multi-agent systems (MAS) treat cities as complex urban systems. While CA focus on their spatial dynamics, MAS are well-suited for capturing autonomous individual decision making. Yet both models are complementary in terms of their focus, status change, mobility, and representations. Hence, the coupling of CA and MAS is a useful way of integrating spatial pattern and non-spatial processes into one modeling infrastructure. The thesis at hand aims at a holistic geosimulation of the future urban sprawl in the Ruhr. This region is particularly challenging as it is characterized by two seemingly antagonistic processes: urban growth and urban shrinkage. Accordingly, a hybrid modeling approach is to be developed as a means of integrating the simulation power of CA and MAS. A modified version of SLEUTH (short for Slope, Land-use, Exclusion, Urban, Transport, and Hillshade) will function as the CA component. SLEUTH makes use of historic urban land-use data sets and growth coefficients for the purpose of modeling physical urban expansion. In order to enhance the simulation performance of the CA and to incorporate important driving forces of urban sprawl, SLEUTH is for the first time combined with support vector machines (SVM). The supported CA will be coupled with ReHoSh (Residential Mobility and the Housing Market of Shrinking City Systems). This MAS models population patterns, housing prices, and housing demand in shrinking regions. All dynamics are based on multiple interactions between different household groups as well as stakeholders of the housing market. Moreover, this thesis will elaborate on the most important driving factors, rates, and most probable locations of urban sprawl in the Ruhr as well as on the future migration tendencies of different household types and the price development in the housing market of a polycentric shrinking region. The results of SLEUTH and ReHoSh are loosely coupled for a spatial analysis in which the municipal differences that have emerged during the simulations are disaggregated. Subsequently, a concept is developed in order to integrate the CA and the MAS into one geosimulation approach. The thesis introduces semi-explicit urban weights as a possibility of assessing settlement-pattern dynamics and the regional housing market dynamics at the same time. The model combination of SLEUTH-SVM and ReHoSh is finally calibrated, validated, and implemented for simulating three different scenarios of individual housing preferences and their effects on the future urban pattern in the Ruhr. Applied to a digital petri dish, the generic urban growth elements of the Ruhr are being detected

Speed Limit Induced CO2 Reduction on Motorways: Enhancing Discussion Transparency through Data Enrichment of Road Networks

Considering climate change, recent political debates often focus on measures to reduce CO2 emissions. One key component is the reduction of emissions produced by motorized vehicles. Since the amount of emission directly correlates to the velocity of a vehicle via energy consumption factors, a general speed limit is often proposed. This article presents a methodology to combine openly available topology data of road networks from OpenStreetMap (OSM) with pay-per-use API traffic data from TomTom to evaluate such measures transparently by analyzing historical real-world circumstances. From our exemplary case study of the German motorway network, we derive that most parts of the motorway network on average do not reach their maximum allowed speed throughout the day due to traffic, construction sites and general road utilization by network participants. Nonetheless our findings prove that the introduction of a speed limit of 120 km per hour on the German autobahn would restrict 50.74% of network flow kilometers for a CO2 reduction of 7.43% compared to the unrestricted state

Metropolitan Research

Metropolitan research requires multidisciplinary perspectives in order to do justice to the complexities of metropolitan regions. This volume provides a scholarly and accessible overview of key methods and approaches in metropolitan research from a uniquely broad range of disciplines including architectural history, art history, heritage conservation, literary and cultural studies, spatial planning and planning theory, geoinformatics, urban sociology, economic geography, operations research, technology studies, transport planning, aquatic ecosystems research and urban epidemiology. It is this scope of disciplinary - and increasingly also interdisciplinary - approaches that allows metropolitan research to address recent societal challenges of urban life, such as mobility, health, diversity or sustainability

Metropolitan Research: Methods and Approaches

Metropolitan research requires multidisciplinary perspectives in order to do justice to the complexities of metropolitan regions. This volume provides a scholarly and accessible overview of key methods and approaches in metropolitan research from a uniquely broad range of disciplines including architectural history, art history, heritage conservation, literary and cultural studies, spatial planning and planning theory, geoinformatics, urban sociology, economic geography, operations research, technology studies, transport planning, aquatic ecosystems research and urban epidemiology. It is this scope of disciplinary - and increasingly also interdisciplinary - approaches that allows metropolitan research to address recent societal challenges of urban life, such as mobility, health, diversity or sustainability

Realistic Cellular Automaton Model for Synchronized Two-Lane Traffic - Simulation, Validation, and Applications

An objective of current traffic-research is the realistic description of vehicular traffic by means of traffic modeling. Since no present traffic model is capable to reproduce all empirical characteristics, the development of such a model is of main interest. Thus, this thesis presents a realistic cellular automaton model for multi-lane traffic and validates it by means of empirical single-vehicle data. In contrast to present approaches a limited deceleration capability is assigned to the vehicles. Moreover, the velocity of the vehicles is determined on the basis of the local neighborhood. Therefore, the drivers are divided into optimistic or pessimistic drivers. The former may underestimate their safety distance if their neighborhood admits it. The latter always keep a safe distance. This results in a convincing reproduction of the microscopic and macroscopic features of synchronized traffic. The anticipation of the leader’s velocity is hereby essential for the reproduction of synchronized traffic. This thesis is divided into three main parts. The first one validates the single-lane model by Lee et al. by means of empirical data. This approach builds the basis for the further developments of this thesis. Then, the fundamental characteristics are summarized. This is followed by new results concerning the comparison with empirical findings that confirm the good reproduction of the reality. The analyses also show the important and fundamental property of synchronized traffic: its density dependent life-time. Nevertheless, accidents appear in the stationary state. Thus, the model approach has to be modified so that it is capable to model multi-lane traffic. The adapted model is enhanced in the next part by a realistic lane change algorithm. A multi-lane model is formulated that reproduces the empirical data even better than the single-lane approach. Moreover, specific two-lane characteristics like the density dependent lane change frequency are reproduced as well as the coupling of the lanes. Moreover, if the velocity difference between the two lanes is too high, the lanes may decouple, i.e., different traffic states emerge on the two lanes. This is a direct consequence of the limited deceleration capability of the vehicles. In the last part of the thesis the two-lane model is applied to open systems with bottlenecks like an on-ramp and a speed-limit. The empirically observed complex structures of the synchronized traffic are reproduced here in great detail. Thus, the approach discussed in this thesis exceeds the present in the degree of realism. Because of the reliability of the presented model it is supposed to be implemented to simulate the whole network of North Rhine-Westphalia.Ziel der aktuellen Verkehrsforschung ist es, den Straßenverkehr durch Verkehrsmodelle realitätsnah zu beschreiben. Da kein bisheriges Modell alle empirisch beobachteten Phänomene exakt nachbilden kann, ist dessen Entwicklung ein aktueller Forschungsschwerpunkt. Daher präsentiert die vorliegende Arbeit ein realitätsnahes Zellularautomaten-Modell für den mehrspurigen Straßenverkehr und validiert dieses anhand empirischer Einzelfahrzeug-Daten. Im Unterschied zu den bisherigen Modellansätzen wird ein begrenztes Bremsvermögen für die Fahrzeuge eingeführt. Darüber hinaus wird die Geschwindigkeit auf Basis der Umgebung des Fahrers bestimmt und die Fahrer in optimistische und pessimistische eingeteilt. Die ersteren können den Sicherheitsabstand unterschreiten, wenn die Umgebung dies zulässt, die letzteren halten dagegen einen sicheren Abstand ein. Im Ergebnis bildet das Modell die mikroskopischen und makroskopischen Eigenschaften des synchronisierten Verkehrs überzeugend nach. Die Antizipation der Geschwindigkeit des vorausfahrenden Fahrzeugs ist dabei für die Reproduktion des synchronisierten Verkehrs wesentlich. Die Arbeit besteht aus drei Teilen. Der erste Teil verifiziert das Einspur-Modell von Lee et al anhand von empirischen Daten, welcher das Basismodell für die weiteren Entwicklungen bildet und dessen grundlegende Eigenschaften zusammengefasst werden. Es folgen neue Ergebnisse aus dem Vergleich zu den empirischen Daten, welche die gute Übereinstimmung mit der Realität bestätigen. Die Analyse des synchronisierten Verkehrs offenbart eine wesentliche Eigenschaft: die Dichteabhängigkeit der Lebensdauer. Da im ursprünglichen Modellansatz Unfälle auftreten können, muss dieses für die Modellierung von Mehrspur-Verkehr auf größere Unfallfreiheit zugeschnitten werden. Das angepasste Modell wird im nächsten Teil um einen realitätsnahen Spurwechselalgorithmus erweitert. Es wird ein wirklichkeitsnahes Modell formuliert, dass die empirischen Daten eines zweispurigen Abschnitts besser reproduziert als das bisherige Einspur-Modell. Der Modellansatz bildet die für den Zweispur-Verkehr spezifischen Charakteristiken nach, insbesondere die dichteabhängige Spurwechselrate. Darüber hinaus sind nebeneinander liegende Fahrspuren bei großen Geschwindigkeitsunterschieden nicht gekoppelt, was eine direkte Konsequenz des beschränkten Bremsvermögens ist. Im letzten Teil dieser Arbeit wird das Zweispur-Modell auf offene Systeme mit Engpässen wie Zufahrten und Geschwindigkeitsbegrenzungen angewendet. Die in der Realität beobachteten komplexen Strukturen des synchronisierten Verkehrs werden hier sehr detailliert nachgebildet, so dass das vorgestellte Modell die bisherigen Ansätze an Realitätsnähe übertrifft. Aufgrund der Zuverlässigkeit des Modells wird in der weitergehenden Forschung der Ansatz auf das gesamte Autobahnnetz des Landes Nordrhein-Westfalen angewendet