1,552 research outputs found
Metro systems : Construction, operation and impacts
Peer reviewedPublisher PD
The ecology of outdoor rape: The case of Stockholm, Sweden
The objective of this article is to report the results of an ecological study into the geography of rape in Stockholm, Sweden, using small area data. In order to test the importance of factors indicating opportunity, accessibility and anonymity to the understanding of the geography of rape, a two-stage modelling approach is implemented. First, the overall risk factors associated with the occurrence of rape are identified using a standard Poisson regression, then a local analysis using profile regression is performed. Findings from the whole-map analysis show that accessibility, opportunity and anonymity are all, to different degrees, important in explaining the overall geography of rape - examples of these risk factors are the presence of subway stations or whether a basområde is close to the city centre. The local analysis reveals two groupings of high risk of rape areas associated with a variety of risk factors: city centre areas with a concentration of alcohol outlets, high residential population turnover and high counts of robbery; and poor suburban areas with schools and large female residential populations where subway stations are located and where people express a high fear of crime. The article concludes by reflecting upon the importance of these results for future research as well as indicating the implications of these results for policy
Hazards threatening underground transport systems
The final publication is available at Springer via http://dx.doi.org/10.1007/s11069-020-03860-wMetro systems perform a significant function for millions of ridership worldwide as urban passengers rely on a secure, reliable, and accessible underground transportation way for their regular conveyance. However, hazards can restrict normal metro service and plans to develop or improve metro systems set aside some way to cope with these hazards. This paper presents a summary of the potential hazards to underground transportation systems worldwide, identifying a knowledge gap on the understanding of water-related impacts on metro networks. This is due to the frequency and scope of geotechnical and air quality hazards, which exceed in extreme magnitude the extreme precipitation events that can influence underground transportation systems. Thus, we emphasize the importance of studying the water-related hazards in metro systems to fill the gaps in this topic.Peer ReviewedPostprint (author's final draft
System importance measures: A new approach to resilient systems-of-systems
Resilience is the ability to withstand and recover rapidly from disruptions. While this attribute has been the focus of research in several fields, in the case of system-of-systems (SoSs), addressing resilience is particularly interesting and challenging. As infrastructure SoSs, such as power, transportation, and communication networks, grow in complexity and interconnectivity, measuring and improving the resilience of these SoSs is vital in terms of safety and providing uninterrupted services. ^ The characteristics of systems-of-systems make analysis and design of resilience challenging. However, these features also offer opportunities to make SoSs resilient using unconventional methods. In this research, we present a new approach to the process of resilience design. The core idea behind the proposed design process is a set of system importance measures (SIMs) that identify systems crucial to overall resilience. Using the results from the SIMs, we determine appropriate strategies from a list of design principles to improve SoS resilience. The main contribution of this research is the development of an aid to design that provides specific guidance on where and how resources need to be targeted. Based on the needs of an SoS, decision-makers can iterate through the design process to identify a set of practical and effective design improvements. ^ We use two case studies to demonstrate how the SIM-based design process can inform decision-making in the context of SoS resilience. The first case study focuses on a naval warfare SoS and describes how the resilience framework can leverage existing simulation models to support end-to-end design. We proceed through stages of the design approach using an agent-based model (ABM) that enables us to demonstrate how simulation tools and analytical models help determine the necessary inputs for the design process and, subsequently, inform decision-making regarding SoS resilience. ^ The second case study considers the urban transportation network in Boston. This case study focuses on interpreting the results of the resilience framework and on describing how they can be used to guide design choices in large infrastructure networks. We use different resilience maps to highlight the range of design-related information that can be obtained from the framework. ^ Specific advantages of the SIM-based resilience design include: (1) incorporates SoS- specific features within existing risk-based design processes - the SIMs determine the relative importance of different systems based on their impacts on SoS-level performance, and suggestions for resilience improvement draw from design options that leverage SoS- specific characteristics, such as the ability to adapt quickly (such as add new systems or re-task existing ones) and to provide partial recovery of performance in the aftermath of a disruption; (2) allows rapid understanding of different areas of concern within the SoS - the visual nature of the resilience map (a key outcome of the SIM analysis) provides a useful way to summarize the current resilience of the SoS as well as point to key systems of concern; and (3) provides a platform for multiple analysts and decision- makers to study, modify, discuss and documentoptions for SoS
The role of road safety in a sustainable urban mobility: An econometric assessment of the Spanish cities
There has been a structural change in mobility in major Spanish cities in recent decades, with a switch to the pattern followed in other countries in the area. A shift has taken place from a traditional Mediterranean model to a North American city stereotype, with uncontrolled motorization and major implications for public health. This article specifically analyzes negative road safety-related externalities that result from this process, given that the trend seems to show a steady decline in road safety accidents on urban roads in Spain, with major differences among NUTS-3 provinces. The objective is to evaluate the factors that empirically explain these differences for the 2003-2013 period using a panel data analysis. (...
HERRAMIENTAS INTELIGENTES PARA LA GESTIÓN DE PROYECTOS
[EN] The application of Artificial Intelligence (AI) in Project Management (PM) is a current
research field with a growing demand from companies and organizations, interested in
applying these technologies to get the most out of their data and expertise. Many
organizations use software tools that allow automating the status of projects (situation
analysis). These tools also provide predictions on the evolution of projects, using
classic techniques such as Earned Value Management (EVM). However, the standard
tools do not have many advanced functionalities, based on AI, which would allow to
take much better advantage of the knowledge acquired by the organization. This fact is
especially important in Risk Management (RM), which is one of the most complex
aspects of PM. The objective of this work is to propose a methodology for research and
development of tools based on AI technologies that allow organizations to analyze
information from projects already developed (historical information) and to use it to
improve RM in the planning of future projects.[ES] La aplicación de la Inteligencia Artificial (IA) en la Gestión de Proyectos (GP) es un
campo de investigación actual y además existe una demanda creciente por parte de
empresas y organizaciones para aplicar estas tecnologías. Muchas organizaciones
utilizan herramientas de software que permiten automatizar el estado de los proyectos
(análisis de situación). Estas herramientas también proporcionan predicciones sobre la
evolución de los proyectos, utilizando técnicas clásicas como la Gestión del Valor
Ganado (EVM). Sin embargo, estas herramientas, en general, no disponen de muchas
funcionalidades avanzadas, basadas en la IA, que permitirían aprovechar mucho mejor
los conocimientos adquiridos por la organización. Este hecho es especialmente
importante en la Gestión de Riesgos (GR), que es uno de los aspectos más complejos
de la GP. El objetivo de este trabajo es proponer una metodología para la investigación
y el desarrollo de herramientas basadas en las tecnologías de la IA que permitan a las
organizaciones analizar la información histórica de los proyectos ya ejecutados
(información histórica) y utilizarla para poder mejorar la GR en la planificación de los
proyectos futuros.Palomares Chust, A.; Heras, S.; Gil Pérez, A. (2020). Intelligent Project Management Tools. Asociación Española de Dirección e Ingeniería de Proyectos (AIEPRO). 1860-1870. http://hdl.handle.net/10251/177493S1860187
The role of road safety in a sustainable urban mobility: An econometric assessment of the Spanish cities
There has been a structural change in mobility in major Spanish cities in recent decades, with a switch to the pattern followed in other countries in the area. A shift has taken place from a traditional Mediterranean model to a North American city stereotype, with uncontrolled motorization and major implications for public health. This article specifically analyzes negative road safety related externalities that result from this process, given that the trend seems to show a steady decline in road safety accidents on urban roads in Spain, with major differences among NUTS-3 provinces. The objective is to evaluate the factors that empirically explain these differences for the 2003-2013 period using a panel data analysis. Results show that a key role is played by urban development variables, such as population density and improvements in health services, with advances linked to more accessible and sustainable urban transportation, such as the Smart City concept. Not only does this article close a gap in the literature, but the findings can also serve as a practical guide for the development and implementation of urban mobility and road safety plans, and reveals the special needs of the most vulnerable groups
A Real-Time Comparison of Four Particulate Matter Size Fractions in the Personal Breathing Zone of Paris Subway Workers: A Six-Week Prospective Study.
We developed a Bayesian spline model for real-time mass concentrations of particulate matter (PM10, PM2.5, PM1, and PM0.3) measured simultaneously in the personal breathing zone of Parisian subway workers. The measurements were performed by GRIMM, a gravimetric method, and DiSCmini during the workers' work shifts over two consecutive weeks. The measured PM concentrations were analyzed with respect to the working environment, the underground station, and any specific events that occurred during the work shift. Overall, PM0.3 concentrations were more than an order of magnitude lower compared to the other PM concentrations and showed the highest temporal variation. The PM2.5 levels raised the highest exposure concern: 15 stations out of 37 had higher mass concentrations compared to the reference. Station PM levels were not correlated with the annual number of passengers entering the station, the year of station opening or renovation, or the number of platforms and tracks. The correlation with the number of station entrances was consistently negative for all PM sizes, whereas the number of correspondence concourses was negatively correlated with PM0.3 and PM10 levels and positively correlated with PM1 and PM2.5 levels. The highest PM10 exposure was observed for the station platform, followed by the subway cabin and train, while ticket counters had the highest PM0.3, PM1, and PM2.5 mass concentrations. We further found that compared to gravimetric and DiSCmini measurements, GRIMM results showed some discrepancies, with an underestimation of exposure levels. Therefore, we suggest using GRIMM, calibrated by gravimetric methods, for PM sizes above 1μm, and DiSCmini for sizes below 700 nm
- …