Search results for "11. Sustainability"
showing 10 items of 257 documents
District heating networks: enhancement of the efficiency
2019
International audience; During the decades the district heating's (DH) advantages (more cost-efficient heat generation and reduced air pollution) overcompensated the additional costs of transmission and distribution of the centrally produced thermal energy to consumers. Rapid increase in the efficiency of low-power heaters, development of separated low heat density areas in cities reduce the competitiveness of the large centralized DH systems in comparison with the distributed cluster-size networks and even local heating. Reduction of transmission costs, enhancement of the network efficiency by optimization of the design of the DH networks become a critical issue. The methodology for determ…
Rotation estimation and vanishing point extraction by omnidirectional vision in urban environment
2012
International audience; Rotation estimation is a fundamental step for various robotic applications such as automatic control of ground/aerial vehicles, motion estimation and 3D reconstruction. However it is now well established that traditional navigation equipments, such as global positioning systems (GPSs) or inertial measurement units (IMUs), suffer from several disadvantages. Hence, some vision-based works have been proposed recently. Whereas interesting results can be obtained, the existing methods have non-negligible limitations such as a difficult feature matching (e.g. repeated textures, blur or illumination changes) and a high computational cost (e.g. analyze in the frequency domai…
Modeling of an active torsion bar automotive suspension for ride comfort and energy analysis in standard road profiles
2019
Abstract Chassis technology is evolving towards active suspension, in which actuators can provide forces to each wheel individually. This overcomes the traditional trade-off between comfort and handling, at the expense of increased complexity and electric consumption. To reduce power demand, regenerative solutions capable of harvesting a certain amount of energy otherwise dissipated in vehicle suspensions and to enhance vehicle dynamics for improving ride comfort and road safety at the same time have been researched. In this paper, an active suspension based on a torsion bar is modeled and analyzed under the excitation from standardized road profiles according to the ISO 8608 norm. A skyhoo…
Omnidirectional vision for UAV: applications to attitude, motion and altitude estimation for day and night conditions
2012
International audience; This paper presents the combined applications of omnidirectional vision featuring on its application to aerial robotics. Omnidirectional vision is first used to compute the attitude, altitude and motion not only in rural environment but also in the urban space. Secondly, a combination of omnidirectional and perspective cameras permits to estimate the altitude. Finally we present a stereo system consisting of an omnidirectional camera with a laser pattern projector enables to calculate the altitude and attitude during the improperly illuminated conditions to dark environments. We demonstrate that omnidirectional camera in conjunction with other sensors is suitable cho…
A Meta-Model for Intelligent Engineering Design of Complex City
2019
A city is a complex system, requiring the input of multiple disciplines for its (re)design. It shares some properties of two kinds of objects: empirical objects as well as theoretical objects. As city emerges as a complex object for multi-disciplinary studies, it is of the highest importance to adopt a systemic and global approach in order to bring new knowledge to this field. To master the growing complexity of cities and to consider in the same spot heterogeneous ways of thinking of city, we need intellectual tools and models. The goal of this paper is to propose a model for describing engineering modelling knowledge with relationships and transformations between four domains: (1) citizen…
Global, regional, and national levels of maternal mortality, 1990–2015: a systematic analysis for the Global Burden of Disease Study 2015
2016
BACKGROUND: In transitioning from the Millennium Development Goal to the Sustainable Development Goal era, it is imperative to comprehensively assess progress toward reducing maternal mortality to identify areas of success, remaining challenges, and frame policy discussions. We aimed to quantify maternal mortality throughout the world by underlying cause and age from 1990 to 2015.METHODS: We estimated maternal mortality at the global, regional, and national levels from 1990 to 2015 for ages 10-54 years by systematically compiling and processing all available data sources from 186 of 195 countries and territories, 11 of which were analysed at the subnational level. We quantified eight underl…
Statistical characterization of deviations from planned flight trajectories in air traffic management
2016
Understanding the relation between planned and realized flight trajectories and the determinants of flight deviations is of great importance in air traffic management. In this paper we perform an in depth investigation of the statistical properties of planned and realized air traffic on the German airspace during a 28 day periods, corresponding to an AIRAC cycle. We find that realized trajectories are on average shorter than planned ones and this effect is stronger during night-time than daytime. Flights are more frequently deviated close to the departure airport and at a relatively large angle to destination. Moreover, the probability of a deviation is higher in low traffic phases. All the…
Pursuing softer urban mobility behaviors through game-based apps
2020
Cities are currently engaged through their urban policies in pushing people towards less environmentally impacting mobility modalities: therefore, cycling and walking are strongly promoted, especially by means of new and wider limited traffic and no-cars zones. In this paper, the effectiveness of the new smartphones and apps-based technologies in modifying the mobility behaviors of citizens towards more sustainable choices has been investigated. Specifically, the potential of a smartphone app, directly involving citizens by means of a game rewarding the most sustainable trips, has been tested on a university commuters' group. These latter, starting from their current mobility situation, wer…
Charitable food aid in Finland: from a social issue to an environmental solution
2019
Since the establishment of the first food bank in 1995, charitable food aid (CFA) has become entrenched in Finland as a seemingly irreplaceable solution to food poverty. Further, it has recently been suggested that the focus of food aid activities is shifting from food poverty and temporary hunger alleviation towards environmental sustainability through addressing food waste via organized re-distribution of expiring food from retail to charitable organizations. This potentially creates a mechanism that (1) solidifies food poverty and (2) fortifies the paradoxical situation where charitable organizations delivering food aid are dependent on food waste rather than trying to reduce it. To unde…
Dimensions fractales et réalités périurbaines. L'exemple du Sud de Bruxelles
2004
This exploratory paper aims at showing how the fractal dimension can be used to characterise the spatial structure of built-up areas within the periurban fringe. The southern periphery of Brussels is considered here. Two estimation techniques (correlation and dilation) are applied to surface areas, and one (correlation after dilation) to the borders of built-up areas. They are applied to windows of fixed size. Fractal dimensions are then compared with traditional socio-economic and morphological indicators. The results are interpreted in the context of urban sprawl and polycentric development of the peripheries. These analyses confirm the usefulness of the fractal approach for describing bu…