4,389 research outputs found

    A stigmergy-based analysis of city hotspots to discover trends and anomalies in urban transportation usage

    Full text link
    A key aspect of a sustainable urban transportation system is the effectiveness of transportation policies. To be effective, a policy has to consider a broad range of elements, such as pollution emission, traffic flow, and human mobility. Due to the complexity and variability of these elements in the urban area, to produce effective policies remains a very challenging task. With the introduction of the smart city paradigm, a widely available amount of data can be generated in the urban spaces. Such data can be a fundamental source of knowledge to improve policies because they can reflect the sustainability issues underlying the city. In this context, we propose an approach to exploit urban positioning data based on stigmergy, a bio-inspired mechanism providing scalar and temporal aggregation of samples. By employing stigmergy, samples in proximity with each other are aggregated into a functional structure called trail. The trail summarizes relevant dynamics in data and allows matching them, providing a measure of their similarity. Moreover, this mechanism can be specialized to unfold specific dynamics. Specifically, we identify high-density urban areas (i.e hotspots), analyze their activity over time, and unfold anomalies. Moreover, by matching activity patterns, a continuous measure of the dissimilarity with respect to the typical activity pattern is provided. This measure can be used by policy makers to evaluate the effect of policies and change them dynamically. As a case study, we analyze taxi trip data gathered in Manhattan from 2013 to 2015.Comment: Preprin

    Integrated design of transport infrastructure and public spaces considering human behavior: A review of state-of-the-art methods and tools

    Get PDF
    In order to achieve holistic urban plans incorporating transport infrastructure, public space and the behavior of people in these spaces, integration of urban design and computer modeling is a promising way to provide both qualitative and quantitative support to decision-makers. This paper describes a systematic literature review following a four-part framework. Firstly, to understand the relationship of elements of transport, spaces, and humans, we review policy and urban design strategies for promoting positive interactions. Secondly, we present an overview of the integration methods and strategies used in urban design and policy discourses. Afterward, metrics and approaches for evaluating the effectiveness of integrated plan alternatives are reviewed. Finally, this paper gives a review of state-of-the-art tools with a focus on seven computer simulation paradigms. This article explores mechanisms underlying the complex system of transport, spaces, and humans from a multidisciplinary perspective to provide an integrated toolkit for designers, planners, modelers and decision-makers with the current methods and their challenges

    Modelling land use and transport policies to measure their contribution to urban challenges: the case of Madrid.

    Get PDF
    Urban areas play a key role in the development of European territories, and it is essential for them to be sustainable and efficient. However, the European cities are facing some challenges related to certain trends that are threatening their sustainable development and operational efficiency. In this paper, we compare the contribution of three policy measures—cordon toll accompanied by public transport improvements, teleworking and re-densification—to address different city challenges. The policy assessment requires a long term simulation tool, i.e., the MARS (Metropolitan Activity Relocation Simulator) model, which is able to consider interactions between land use and transport systems. The simulations of the different policy scenarios were carried out for the case of Madrid in the period 2012–2031. The contribution of the policy measures to address the city challenges was measured through different indicators. The results indicated that the three policy measures contributed to the time efficiency challenge, by saving time for the commute, reducing congestion and improving the traffic flows at peak hours. The most effective policy in this regard is the teleworking measure. Another challenge addressed by the three policies was the accessibility to PT. The three policy scenarios, when simulated, showed higher PT use, especially the cordon toll scenario. However, the only policy that really contributed to the energy, emissions and pollution city challenges was the re-densification measure, which reduced travel distances and encouraged a mobility that relies more on PT and slow modes

    Physics for secure and efficient societies

    Get PDF

    Combining multi-criteria and space syntax analysis to assess a pedestrian network: the case of Oporto

    Get PDF
    This paper describes a GIS-based integrated approach to assess a pedestrian network by combining multi-criteria and space syntax. The analysis combines pedestrian attributes with street connectivity and both factors were evaluated by a group of experts. The approach was adopted in the city of Oporto. Results show that the city centre offers various conditions; however, overall they are poor for pedestrians. Moreover, the streets which scored best are not integrated into the network. The described approach can potentially be replicated in other cities in terms of improving the walkability and promoting sustainable urban mobility.This research was funded by the CIVITAS CAPITAL (Ref. No. MOVE/FP7/604778/CAPITAL) and by the Centre for Territory, Environment and Construction of the School of Engineering of University of Minho.info:eu-repo/semantics/publishedVersio

    2020 NASA Technology Taxonomy

    Get PDF
    This document is an update (new photos used) of the PDF version of the 2020 NASA Technology Taxonomy that will be available to download on the OCT Public Website. The updated 2020 NASA Technology Taxonomy, or "technology dictionary", uses a technology discipline based approach that realigns like-technologies independent of their application within the NASA mission portfolio. This tool is meant to serve as a common technology discipline-based communication tool across the agency and with its partners in other government agencies, academia, industry, and across the world

    Modelling and Simulation of Human-Environment Interactions

    Get PDF
    Computational models provide intelligent environmental decision support systems to understand how human decisions are shaped by, and contribute to changes in, the environment. These models provide essential tools to tackle the important issues raised by climate change, including migrations and conflicts due to resource scarcity (e.g., water resources), while accounting for the necessity of co-managing ecosystems across a population of stakeholders with diverse goals. Such socio-environmental systems are characterized by their complexity, which is reflected by an abundance of open questions. This book explores several of these open questions, based on the contributions from over 50 authors. While several books account for methodological developments in modeling socio-environmental systems, our book is unique in combining case studies, methodological innovations, and a holistic approach to training the next generation of modelers. One chapter covers the ontological, epistemological, and ethical issues raised at the intersection of sustainability research and social simulation. In another chapter, we show that the benefits of simulations are not limited to managing complex eco-systems, as they can also serve an educational mission in teaching essential rules and thus improve systems thinking competencies in the broader population

    Technology for the Future: In-Space Technology Experiments Program, part 2

    Get PDF
    The purpose of the Office of Aeronautics and Space Technology (OAST) In-Space Technology Experiments Program In-STEP 1988 Workshop was to identify and prioritize technologies that are critical for future national space programs and require validation in the space environment, and review current NASA (In-Reach) and industry/ university (Out-Reach) experiments. A prioritized list of the critical technology needs was developed for the following eight disciplines: structures; environmental effects; power systems and thermal management; fluid management and propulsion systems; automation and robotics; sensors and information systems; in-space systems; and humans in space. This is part two of two parts and contains the critical technology presentations for the eight theme elements and a summary listing of critical space technology needs for each theme
    • …
    corecore