La part de la doctrine dans la création du droit constitutionnel

A la réflexion, la part de la doctrine dans la création du droit constitutionnel est nulle ou quasi nulle. Mais on peut se demander si la doctrine sert à quelque chose d'autre qu'enseigner le droit constitutionnel que créent ceux qui en ont effectivement le pouvoir. La réponse est alors doublement positive : d'une part, la doctrine peut être utilisée comme un bazar institutionnel et, d'autre part, elle peut aussi faire office de précepteur de principes prétendument rationnels

The Tolerability of Risk

peer reviewe

Policies and Deployment for Fuel Cell Electric Vehicles An Assessment of the Normandy Project

The paper provides a cost benefit analysis of one of the most prominent deployment project in France of fuel cell electric vehicles, taking place in Normandy. The project builds on the substitution of a diesel Renault Kangoo by an electric Renault Kangoo ZE with afuel cell range extender for public fleets. The analysis points out potential weaknesses of the project as it is envisioned today using a decomposition of the value-chain. To achieve sustainability in 2025 a much stronger deployment should take place. This would allow for a sharp decrease in the total cost of ownership thanks to a close coordination between hydrogen production and its delivery through refilling stations to take advantage of the expected increasing volume of hydrogen consumption along the deployment path. Thissuggests that a high level in public funds at this early deployment phase can be critical for the success of the project

Universality of Tip Singularity Formation in Freezing Water Drops

A drop of water deposited on a cold plate freezes into an ice drop with a pointy tip. While this phenomenon clearly finds its origin in the expansion of water upon freezing, a quantitative description of the tip singularity has remained elusive. Here we demonstrate how the geometry of the freezing front, determined by heat transfer considerations, is crucial for the tip formation. We perform systematic measurements of the angles of the conical tip, and reveal the dynamics of the solidification front in a Hele-Shaw geometry. It is found that the cone angle is independent of substrate temperature and wetting angle, suggesting a universal, self-similar mechanism that does not depend on the rate of solidification. We propose a model for the freezing front and derive resulting tip angles analytically, in good agreement with observations.Comment: Letter format, 5 pages, 3 figures. Note: authors AGM and ORE contributed equally to the pape

La perception sociale des risques: étude de cas sur les champs électromagnétiques en Belgique

Dans le cadre de cette étude, nous avons voulu mesurer la perception sociale du risque relatif à l’exposition aux champs électromagnétiques. Notre objectif était d’identifier les modes de connaissances auxquels se référent des individus qui font face à un risque empreint d’un niveau élevé d’incertitude scientifique. Comment ce public, mobilisé autour d’une problématique complexe, acquiert-il un niveau d’expertise suffisant pour comprendre les enjeux multiples (sociaux, économiques, éthiques, politiques et environnementaux) d’une technologie sur la société et ses modes d’organisation ? Quelle vision a-t-il des acteurs politiques et subpolitiques (Beck, 2001) qui prennent part aux débats ? Quel niveau de confiance accorde-t-il à un monde politique qui, en cas de risque majeur, pourrait invoquer une démarche précautionneuse et récupérer une partie du pouvoir décisionnel qui semblait lui échapper (Brunet, Delvenne & Joris, 2007) ? En situation de haute incertitude scientifique, qui sont les experts ? Quelle relation entretiennent les différents stakeholders 1 avec les autorités publiques? Le risque électromagnétique constitue un exemple éclairant de nouveau risque technologique, qui suscite une mobilisation sociale particulière et met en évidence les défis technologiques, sociaux, éthiques et politiques que nos sociétés occidentales doivent affronter à l’aube du XXIe siècle

The deployment of BEV and FCEV in 2015

In Europe the transport sector contributes about 25% of total GHG emissions, 75% of which come from road transport. Contrarily to industrial emissions road emissions have increased over the period 1990-2015 in OECD countries: California (+26%), Germany (0%), France (+12%), Japan (+2%), Denmark (+30%). The number of registered vehicles on road in these countries amounts respectively to: California (33 million), Germany (61.5 million), France (38 million), Japan (77 million), Denmark (4 million). Even if these numbers are not expected to grow in the future this calls for major programs to reduce the corresponding GHG emissions in order to achieve the global GHG targets for 2050. The benefits from these programs will spread out to non OECD countries in which road emissions are bound to increase. Programs to promote zero emissions vehicles (ZEV) effectively started in the 2000’s through public private partnerships involving government agencies, manufacturers, utilities and fuel companies. These partnerships provided subsidies for R&D, pilot programs and infrastructure. Moreover, technical norms for emissions, global requirements for the portfolio of sales for manufacturers, rebates on the purchasing price for customers as well as various perks (driving bus lanes, free parking, etc.) are now in place. These multiple policy instruments constitute powerful incentives to orient the strategies of manufacturers and to stimulate the demand for ZEV. The carbon tax on the distribution of fossil fuels, whenever it exists, remains low and, at this stage, cannot be considered as an important driving force. The cases studies reveal important differences for the deployment of battery electric vehicle (BEV) versus fuel cell electric vehicle (FCEV). BEV is leading the game with a cheaper infrastructure investment cost and a lower cost for vehicle. The relatively low autonomy makes BEV mostly suited for urban use, which is a large segment of the road market. The current level of BEV vehicles on roads starts to be significant with California (70,000), Germany (25,000), France (31,000), Japan (608,000) Denmark (3,000), but they remain very low relative to the targets for 2020: California (1.5 million), Germany (1 million), France (2 million), Japan (0.8-1.1 million for ZEV new registrations), Denmark (0.25 million). The developments and efficiency gains in battery technology along with subsidies for battery charging public stations are expected to facilitate the achievement of the growth. The relative rates of equipment (number of publicly available stations / number of BEV) provide indirect evidence on the effort made in the different countries: California (3%), Germany (12%), France (28%), Japan (11%), and Denmark (61%). In some countries public procurement plays a significant role. In France Autolib (publicly available cars in towns) represents a large share of the overall BEV deployment (12%), and the government recently announced a 50% target for low emissions in all public vehicles new equipment. FCEV is still in an early deployment stage due to a higher infrastructure investment cost and a higher cost for vehicle. The relatively high autonomy combined with speed refueling make FCEV mostly suited for long distance and interurban usage. At present there are only a very limited numbers of HRS deployed: California (28), Germany (15), France (6), Japan (31), Japan (7), Denmark (7), and only a few units of H2 vehicles on road: California (300), Germany (125), France (60), Japan (7), Denmark (21). However, a detailed analysis of the current road maps suggests that FCEV has a large potential. Targets for the 2025-2030 horizons are significant in particular in Germany (4% in 2030), Denmark (4.5% in 2025) and Japan (15-20% for ZEV new registrations in 2020). The California ARB has recently redefined its program (subsidies and mandates) to provide higher incentives for FCEV. France appears to focus on specialized regional submarkets to promote FCEV (such as the use of H2 range extending light utility vehicles). The financing of the H2 infrastructure appears as a bottleneck for FCEV deployment. Roadmaps address this issue through progressive geographical expansion (clusters) and a high level of public subsidies hydrogen refueling station (HRS) in particular in all countries except France. At this stage of BEV and FCEV do not appear as direct competitors; they address distinct market segments. Unexpected delays in the development of infrastructure in FCEV, possible breakthroughs in battery technology, and the promotion of national champions may change the nature of this competition, making it more intense in the future

Exact expressions for vector mode cutoff in three-layer step-index fibers

Two-layer step-index fibers have well-known cutoff solutions, while cutoff solutions for three-layer step-index fiber exist for only one geometry (ring fiber). We derive exact expressions for cutoff frequencies of both vector and scalar modes for all geometries of three-layer step-index fibers. While vector modes have been solved for these fibers, to the best of our knowledge, this is the first time cutoff expressions are reported. Expressions for cutoff help predict the number of supported modes for a given fiber profile. Using these cutoff expressions, we deduce characteristics of fiber modal content as a function of fiber profile

On the concept of political representation

URL del artículo en la web de la Revista: https://www.upo.es/revistas/index.php/ripp/article/view/3689En el presente texto se reflexiona acerca del concepto de representación política. Se plantean, en un primer momento, las dificultades que conlleva la tarea de elaborar una teoría de la representación, tanto desde el punto de vista jurídico como político. Posteriormente, se realiza un análisis del concepto en dos momentos históricos esenciales: la Revolución francesa y la de los Estados Unidos de América. Por último, se estudian las relaciones entre el concepto de representación y el parlamentarismo.In this work we reflect upon the concept of Political Representation. First, the dif fi culties involved in the task of developing a Theory of Representation are posed, both from the legal and political point of views. Next, we carry out an analysis of this notion in two key historical moments: namely, the French and American Revolutions. As a closure, we study the relationships between the concepts of Representation and Parliamentary system.Universidad Pablo de Olavid

ACERCA DEL CONCEPTO DE REPRESENTACIÓN POLÍTICA

En el presente texto se refl exiona acerca del concepto de representación política. Se plantean, en un primer momento, las difi cultades que conlleva la tarea de elaborar una teoría de la representación, tanto desde el punto de vista jurídico como político. Posteriormente, se realiza un análisis del concepto en dos momentos históricos esenciales: la Revolución francesa y la de los Estados Unidos de América. Por último, se estudian las relaciones entre el concepto de representación y el parlamentarismo