Absolute and Relative Deprivation and the Measurement of Poverty

This paper develops the link between poverty and inequality by focussing on a class of poverty indices (some of them well-known) which aggregate normative concerns for absolute and relative deprivation. The indices are distinguished by a parameter that captures the ethical sensitivity of poverty measurement to ``exclusion'' or ``relative-deprivation'' aversion. We also show how the indices can be readily used to predict the impact of growth on poverty. An illustration using LIS data finds that he United States show more relative deprivation than Denmark and Belgium whatever the percentiles considered, but that overall deprivation comparisons of the four countries considered will generally necessarily depend on the intensity of the ethical concern for relative deprivation. The impact of growth on poverty is also seen to depend on the presence of and on the attention granted to concerns over relative deprivation. }Poverty, relative deprivation, inequality, poverty alleviation

Priority-based intersection management with kinodynamic constraints

We consider the problem of coordinating a collection of robots at an intersection area taking into account dynamical constraints due to actuator limitations. We adopt the coordination space approach, which is standard in multiple robot motion planning. Assuming the priorities between robots are assigned in advance and the existence of a collision-free trajectory respecting those priorities, we propose a provably safe trajectory planner satisfying kinodynamic constraints. The algorithm is shown to run in real time and to return safe (collision-free) trajectories. Simulation results on synthetic data illustrate the benefits of the approach.Comment: to be presented at ECC2014; 6 page

Asymptotic analysis of the Poisson-Boltzmann equation describing electrokinetics in porous media

We consider the Poisson-Boltzmann equation in a periodic cell, representative of a porous medium. It is a model for the electrostatic distribution of $N$ chemical species diluted in a liquid at rest, occupying the pore space with charged solid boundaries. We study the asymptotic behavior of its solution depending on a parameter $\beta$ which is the square of the ratio between a characteristic pore length and the Debye length. For small $\beta$ we identify the limit problem which is still a nonlinear Poisson equation involving only one species with maximal valence, opposite to the average of the given surface charge density. This result justifies the {\it Donnan effect}, observing that the ions for which the charge is the one of the solid phase are expelled from the pores. For large $\beta$ we prove that the solution behaves like a boundary layer near the pore walls and is constant far away in the bulk. Our analysis is valid for Neumann boundary conditions (namely for imposed surface charge densities) and establishes rigorously that solid interfaces are uncoupled from the bulk fluid, so that the simplified additive theories, such as the one of the popular Derjaguin, Landau, Verwey and Overbeek (DLVO) approach, can be used. We show that the asymptotic behavior is completely different in the case of Dirichlet boundary conditions (namely for imposed surface potential)

Back-pressure traffic signal control with unknown routing rates

The control of a network of signalized intersections is considered. Previous works proposed a feedback control belonging to the family of the so-called back-pressure controls that ensures provably maximum stability given pre-specified routing probabilities. However, this optimal back-pressure controller (BP*) requires routing rates and a measure of the number of vehicles queuing at a node for each possible routing decision. It is an idealistic assumption for our application since vehicles (going straight, turning left/right) are all gathered in the same lane apart from the proximity of the intersection and cameras can only give estimations of the aggregated queue length. In this paper, we present a back-pressure traffic signal controller (BP) that does not require routing rates, it requires only aggregated queue lengths estimation (without direction information) and loop detectors at the stop line for each possible direction. A theoretical result on the Lyapunov drift in heavy load conditions under BP control is provided and tends to indicate that BP should have good stability properties. Simulations confirm this and show that BP stabilizes the queuing network in a significant part of the capacity region.Comment: accepted for presentation at IFAC 2014, 6 pages. arXiv admin note: text overlap with arXiv:1309.648

Efficiency in the multinational federal republic

The paper is divided in three sections. In the first section, I question the use of the statist redistributive paradigm in federalism. In the second section, I argue that efficiency is a moral principle and that it has a strong normative appeal, especially in contexts of diversity. I show that adopting efficiency as a guiding principle to think of the role of the state, especially in contexts of pluralism, as in MNF, allows us to consider the division of competences in a way that is yet unexplored in political philosophy. Furthermore, I argue that embracing efficiency allows us to avoid the moral problems that other moral approaches encounter, especially as I will defend a non-utilitarian conception of efficiency. That also allows me to show that if one opts for the view that pictures federalism as an efficiency maximizing enterprise, it does not lead to a libertarian conception of federalism. Finally, I try to briefly sketch a possible connection between the principle of efficiency and republican ideal of ‘non-domination’ (Pettit 2012). More specifically I suggest that the pursuit of ‘non-domination’ is totally compatible with the pursuit of efficiency in MNF. In other words, the federal government can interfere to resolve government failures at the sub-unit level, for instance externalities, without being or becoming a dominating agent. The ideal of non-domination supports the sort of strong government interventions defended by egalitarians without having to compromise on the autonomy of federated entities. The combination of efficiency and non-domination ends with a defense of asymmetrical federal arrangements, without sacrificing the equality that states ought to preserve

Role of non-ideality for the ion transport in porous media: derivation of the macroscopic equations using upscaling

This paper is devoted to the homogenization (or upscaling) of a system of partial differential equations describing the non-ideal transport of a N-component electrolyte in a dilute Newtonian solvent through a rigid porous medium. Realistic non-ideal effects are taken into account by an approach based on the mean spherical approximation (MSA) model which takes into account finite size ions and screening effects. We first consider equilibrium solutions in the absence of external forces. In such a case, the velocity and diffusive fluxes vanish and the equilibrium electrostatic potential is the solution of a variant of Poisson-Boltzmann equation coupled with algebraic equations. Contrary to the ideal case, this nonlinear equation has no monotone structure. However, based on invariant region estimates for Poisson-Boltzmann equation and for small characteristic value of the solute packing fraction, we prove existence of at least one solution. To our knowledge this existence result is new at this level of generality. When the motion is governed by a small static electric field and a small hydrodynamic force, we generalize O'Brien's argument to deduce a linearized model. Our second main result is the rigorous homogenization of these linearized equations and the proof that the effective tensor satisfies Onsager properties, namely is symmetric positive definite. We eventually make numerical comparisons with the ideal case. Our numerical results show that the MSA model confirms qualitatively the conclusions obtained using the ideal model but there are quantitative differences arising that can be important at high charge or high concentrations.Comment: 46 page

Dynamique des Brûlis dans les Aires Protégées du Réseau SUN [Bénin, Burkina Faso, Niger et Sénégal] - Saison Sèche 2007-2008: Octobre 2007 - Mars 2008

Le CCR a effectué un suivi systématique des feux dans les 5 aires protégées du réseau SUN [forêt classées de Patako et de Boulon ; parcs nationaux du W-du-Bénin, W-du-Burkina et W-du-Niger] pendant la saison sèche 2007-2008, sur la base d¿images à moyenne résolution acquises par le capteur MODIS installé à bord des satellites Terra et Aqua. L¿élaboration de ces données a permis i)l¿inventaire hebdomadaire des épisodes de feu ; ii)la cartographie des surfaces brûlées, en moyenne deux fois par mois ; iii)l¿établissement d¿un Bulletin Hebdomadaire d¿Information sur les feux, à destination des membres du réseau et des équipes de gestion des aires protégées concernées. Par ailleurs il est montré comment le rapport entre la densité des feux [nombre de feux / 1000 ha] à l¿extérieur et à l¿intérieur d¿une aire protégée constitue un bon indicateur de différenciation de l¿aire par rapport à l¿espace environnant, en termes de disponibilité et d¿agencement spatial du combustible. C¿est une indication i) de la qualité de l¿habitat naturel dans l¿aire; ii) de son degré d¿isolement; iii) de son niveau de protection. Dénommé Indice de Spécificité dans ce document, ce rapport constitue un bon outil de suivi et de comparaison des aires protégées. Il a été utilisé pour comparer les situations observées dans les aires du réseau SUN avec celles prévalant dans les 33 autres parcs nationaux du domaine soudanien d¿Afrique sub-saharienne.JRC.DDG.H.3-Global environement monitorin

Fire Activity Inside and Outside Protected Areas in Sub-Saharan Africa: A Continental Analysis of Fire and its Implications for Biodiversity and Land Management

Fire is an important ecological factor in many natural ecosystems. Without doubt one of the biomes with the highest fire activity in the world is the African savannah. Savannahs have evolved with fires since climate in these regions is characterized by definite dry and wet seasons that create the conditions for burning. During the wet months the herbaceous vegetation shows a quick growth, followed by a long dry period during which the abundant build-up of fine materials becomes highly flammable and most of fires occur. Animals and plants are adapted to these conditions and their lives depend on recurrent fires. In this context fire becomes an essential element to promote biodiversity and nature conservation. Park managers are using programmed fires as a tool to maintain the habitats and favorable conditions to the animal communities. Satellite products like burned areas and active fire maps are a valuable mean to analyze the fire activity and provide support to experts working for conservation and natural resource management. In the framework of the Digital Observatory for Protected Areas (DOPA), the MONDE group (Monitoring Natural Resources for Development) of the Joint Research Centre of the European Commission is using satellite products to analyze the fire occurrence and its effects on protected areas located in sub-Saharan Africa. Information on the fire activity was derived from the MODIS fire products (active fires and burned areas) and allows the DOPA to provide support to park managers as well as to experts working for conservation and natural resource management. We assessed 741 protected areas classified by the IUCN (International Union for Conservation of Nature) with a level of protection between class I and IV. The MODIS datasets are available since the year 2000 and were used to characterize the spatio-temporal distribution of fires over a period of 10 years. Information on fire activity was extracted for the protected areas and a 25km buffer zone around each of them. The region outside the protected areas was used for comparison in order to identify differences or similarities between their fire activities. This also contributed to understand how management and conservation influence fire and assess the level of isolation of the protected areas. The long time series allowed the identification of trends and the interannual variability in the fire activity. The dry season length was determined using FEWS RFE rainfall data (implemented at NOAA's Climate Prediction Center). Within each dry season we identified three periods (early, middle and late) in order to characterize the climatic and environmental conditions at which fires occur and identify trends and patterns. Every period of the dry season lasts two months and shows different conditions of temperature and drought level. Fire activity was characterized combining the information on active fires and burned areas. For each year we determined the fire seasonality, the fire frequency, the main vegetation types affected, the extent and intensity of burning. This information was also used to distinguish management fires from those related to other human activities like transhumance, agriculture and poaching in order to identify possible sources of threat to the protected areas. Information on the road network, the location of villages and cultivated fields were also included. Future work will include a combined analysis of fire activity and land-cover, land-cover change information so that management plans adopted in protected areas can be evaluated in their effectiveness to promote biodiversity and nature conservation.JRC.DDG.H.3-Global environement monitorin