Applying complexity science to air traffic management

Complexity science is the multidisciplinary study of complex systems. Its marked network orientation lends itself well to transport contexts. Key features of complexity science are introduced and defined, with a specific focus on the application to air traffic management. An overview of complex network theory is presented, with examples of its corresponding metrics and multiple scales. Complexity science is starting to make important contributions to performance assessment and system design: selected, applied air traffic management case studies are explored. The important contexts of uncertainty, resilience and emergent behaviour are discussed, with future research priorities summarised

Simulating infrastructure networks in the Yangtze River Delta (China) using generative urban network models

This paper explores the urban-geographical potential of simulation approaches combining spatial and topological processes. Drawing on Vértes et al.'s (2012) economical clustering model, we propose a generative network model integrating factors captured in traditional spatial models (e.g., gravity models) and more recently developed topological models (e.g., actor-oriented stochastic models) into a single framework. In our urban network-implementation of the generative network model, it is assumed that the emergence of inter-city linkages can be approximated through probabilistic processes that speak to a series of contradictory forces. Our exploratory study focuses on the outline of the infrastructure networks connecting prefecture-level cities in the highly urbanized Yangtze River Delta (China). Possible hampering factors in the emergence of these networks include distance and administrative boundaries, while stimulating factors include a measure of city size (population, gross domestic product) and a topological rule stating that the formation of connections between cities sharing nearest neighbors is more likely (i.e., a transitive effect). Based on our results, two wider implications of our research are discussed: (1) it confirms the potential of the proposed method in urban network simulation in that the inclusion of a topological factor alongside geographical factors generates an urban network that better approximates the observed network; (2) it allows exploring the differential extent to which driving forces influence the structure of different urban networks. For instance, in the Yangtze River Delta, transitivity plays a less important role in the Internet-network formation; GDP and boundaries more strongly affect the rail network; and distance decay effects play a more prominent role in the road network

Incorporating geographic interdependencies into the resilience assessment of multimodal public transport networks

Severe weather events, such as snowfall, flooding and storms, may affect wide geographical areas and adversely impact discrete transport infrastructure networks (e.g. road, rail) at the same time, thus revealing the existence of geographic interdependencies between these networks. In this paper, we develop two accessibility-based measures to assess the impact of geographic interdependency on resilience based on the concepts of redundancy and substitutability, respectively. These measures are applied to the railway and long-distance bus networks in Scotland. Results reveal that the combined effect of redundancy and substitutability on the accessibility of locations offered by these discrete modes is reduced due to geographic interdependencies, with the extent of losses being positively associated with the spatial footprint of potential events. The results can be used to identify parts of the network where the potential impacts of geographic interdependencies are greatest, and thus require more in-depth scrutiny by network managers

From Social Simulation to Integrative System Design

As the recent financial crisis showed, today there is a strong need to gain "ecological perspective" of all relevant interactions in socio-economic-techno-environmental systems. For this, we suggested to set-up a network of Centers for integrative systems design, which shall be able to run all potentially relevant scenarios, identify causality chains, explore feedback and cascading effects for a number of model variants, and determine the reliability of their implications (given the validity of the underlying models). They will be able to detect possible negative side effect of policy decisions, before they occur. The Centers belonging to this network of Integrative Systems Design Centers would be focused on a particular field, but they would be part of an attempt to eventually cover all relevant areas of society and economy and integrate them within a "Living Earth Simulator". The results of all research activities of such Centers would be turned into informative input for political Decision Arenas. For example, Crisis Observatories (for financial instabilities, shortages of resources, environmental change, conflict, spreading of diseases, etc.) would be connected with such Decision Arenas for the purpose of visualization, in order to make complex interdependencies understandable to scientists, decision-makers, and the general public.Comment: 34 pages, Visioneer White Paper, see http://www.visioneer.ethz.c

Designing and Operating Safe and Secure Transit Systems: Assessing Current Practices in the United States and Abroad, MTI Report 04-05

Public transit systems around the world have for decades served as a principal venue for terrorist acts. Today, transit security is widely viewed as an important public policy issue and is a high priority at most large transit systems and at smaller systems operating in large metropolitan areas. Research on transit security in the United States has mushroomed since 9/11; this study is part of that new wave of research. This study contributes to our understanding of transit security by (1) reviewing and synthesizing nearly all previously published research on transit terrorism; (2) conducting detailed case studies of transit systems in London, Madrid, New York, Paris, Tokyo, and Washington, D.C.; (3) interviewing federal officials here in the United States responsible for overseeing transit security and transit industry representatives both here and abroad to learn about efforts to coordinate and finance transit security planning; and (4) surveying 113 of the largest transit operators in the United States. Our major findings include: (1) the threat of transit terrorism is probably not universal—most major attacks in the developed world have been on the largest systems in the largest cities; (2) this asymmetry of risk does not square with fiscal politics that seek to spread security funding among many jurisdictions; (3) transit managers are struggling to balance the costs and (uncertain) benefits of increased security against the costs and (certain) benefits of attracting passengers; (4) coordination and cooperation between security and transit agencies is improving, but far from complete; (5) enlisting passengers in surveillance has benefits, but fearful passengers may stop using public transit; (6) the role of crime prevention through environmental design in security planning is waxing; and (7) given the uncertain effectiveness of antitransit terrorism efforts, the most tangible benefits of increased attention to and spending on transit security may be a reduction in transit-related person and property crimes

Logistics management of the rail connections using graph theory: the case of a public transportation company on the example of Koleje Dolnośląskie S.A.

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Structural Analysis of the Pomeranian Metropolitan Railway Transport Network

Public transport is one of the most important elements in the development of the economy and the social space in which it is located. Therefore, it is very important for the area to properly organize and plan a smooth and fault-tolerant transport network that will facilitate transport in the area. The paper analyzes the structural - using graph theory - the railway network of the Pomorska Kolej Metropolitalna to assess its structure in terms of its organizational and functional application. This network is used inter alia to co-implement public transport within Tri-City and Kashubia

Comprehensive review on risk assessment methodologies for HAZMAT transportation between 1995-2015

Issue related to safety, health and environmental has become major priority to be concerned of in the transportation of hazardous materials (HAZMAT) worldwide. Due to the high risk that entailed in the operation of HAZMAT transportation, many accidents in this industry have been reported which include chemicals spillage, fire and explosion. In order to quantify the degree of hazards and risks of these accidents, various assessment methods have been introduced either by the academia, the industry as well as the authority. The methods present various approaches for the assessment, ranging from a simple to highly complicated ones depending on the purpose of the assessment and the available resources and constraints. To date there is yet any study conducted to review those available methods. This paper intends to present a comprehensive review of the existing methods for hazards and risks assessment of HAZMAT transportation between years 1995-2015 which considers road, marine, railway, air and pipeline system. Based on careful screening of the abundance of methods available, 151 of them were selected – that is those specifically meant for hazards and risks assessment of HAZMAT transportation only. The methods are reviewed in terms of the types of assessment; either qualitative, quantitative or hybrid techniques, as well as their specific application in different mode of transportation. Also, statistical analysis was performed to determine the trend of past publications regarding on the type of journal, year of publication and also financial support received in the context of hazard and risk assessment of HAZMAT transportation

Analiza strukturalna sieci transportowej Kolei Wielkopolskich

Public transport is one of the most important elements in the development of the economy and the social space in which it functions. It is therefore very important to properly organize and plan a smooth and resilient transport network that will meet the stated objectives of public transport, both economic and social. The article presents a structural analysis with the use of graph theory for the Koleje Wielkopolskie [Wielkopolskie Railways] railway network to assess its structure in terms of the organizational and functional aspects. The network is used, among others, in co-realization of the public transport within the Warsaw agglomeration and the surrounding areas.Transport publiczny stanowi jeden z najważniejszych elementów rozwoju gospodarki oraz przestrzeni społecznej, na której występuje. W związku z tym bardzo istotne jest prawidłowe zorganizowanie oraz zaplanowanie sprawnej i odpornej na zakłócenia sieci transportowej, która umożliwi uzyskanie zakładanych celów stawianych przed transportem publicznym, zarówno tych gospodarczych, jak i społecznych. W artykule dokonano analizy strukturalnej – z wykorzystaniem teorii grafów – sieci kolejowej Kolei Wielkopolskich celem oceny jej struktury pod kątem organizacyjnym i funkcjonalnym. Sieć ta wykorzystywana jest m.in. do współrealizacji transportu zbiorowego w obrębie Aglomeracji Poznańskiej oraz okolicznych terenów

Strategies for sustainable socio-economic development and mechanisms their implementation in the global dimension

The authors of the book have come to the conclusion that it is necessary to effectively use modern approaches to developing and implementation strategies of sustainable socio-economic development in order to increase efficiency and competitiveness of economic entities. Basic research focuses on economic diagnostics of socio-economic potential and financial results of economic entities, transition period in the economy of individual countries and ensuring their competitiveness, assessment of educational processes and knowledge management. The research results have been implemented in the different models and strategies of supply and logistics management, development of non-profit organizations, competitiveness of tourism and transport, financing strategies for small and medium-sized enterprises, cross-border cooperation. The results of the study can be used in decision-making at the level the economic entities in different areas of activity and organizational-legal forms of ownership, ministries and departments that promote of development the economic entities on the basis of models and strategies for sustainable socio-economic development. The results can also be used by students and young scientists in modern concepts and mechanisms for management of sustainable socio-economic development of economic entities in the condition of global economic transformations and challenges