Participatory Democracy in Local Government: An Online Platform in the City of Madrid

In 2015, the local government of the city of Madrid (Spain) introduced an electronic participation system. This initiative stemmed mainly from the social movements that had occupied the squares of many Spanish cities since 2011. As a result of the local elections in 2015, many of those same activists gained institutional power, took citizens’ participation very seriously, and decided to use the possibilities offered by the internet for political and administrative participation. In this article, we seek to assess the impacts of the Madrid city government with the e-democracy experiment – based mainly on establishing an online platform to facilitate citizen participation in political and administrative decision processes. Drawing on qualitative and documental data, our research indicates that whereas the overall aim of the project was to give citizens a say in local policy and decision making, our case study shows that participation was very low since most of the population does not feel concerned by these processes. Indeed, one of our findings showed that citizens’ involvement offline surpassed in some cases their online participation. To identify who is politically active online and offline is a great challenge, to which the promoters of the project did not pay much attention. Although e-participation was meagre in relation to the electoral turnout, the case study also shows that many proposals from the public were incorporated into the local policies, indicating that from a qualitative point of view, e-participation influences decision-making processes. Perhaps local governments should use a more strategic and integrated approach towards the use of electronic technologies to foster and motivate citizens’ involvement in local politics and administration. This more integrated approach should be less dependent on ideological incentives, more institutionalized, and must incorporate citizens’ perceptions and inputs before the introduction of new technologies

The inception of Symplectic Geometry: the works of Lagrange and Poisson during the years 1808-1810

The concept of a symplectic structure first appeared in the works of Lagrange on the so-called "method of variation of the constants". These works are presented, together with those of Poisson, who first defined the composition law called today the "Poisson bracket". The method of variation of the constants is presented using today's mathematical concepts and notations.Comment: Presented at the meeting "Poisson 2008" in Lausanne, July 2008. Published in Letters in Mathematical Physics. 22 page

Biomimetic flow fields for proton exchange membrane fuel cells: A review of design trends

Bipolar Plate design is one of the most active research fields in Polymer Electrolyte Membrane Fuel Cells (PEMFCs) development. Bipolar Plates are key components for ensuring an appropriate water management within the cell, preventing flooding and enhancing the cell operation at high current densities. This work presents a literature review covering bipolar plate designs based on nature or biological structures such as fractals, leaves or lungs. Biological inspiration comes from the fact that fluid distribution systems found in plants and animals such as leaves, blood vessels, or lungs perform their functions (mostly the same functions that are required for bipolar plates) with a remarkable efficiency, after millions of years of natural evolution. Such biomimetic designs have been explored to date with success, but it is generally acknowledged that biomimetic designs have not yet achieved their full potential. Many biomimetic designs have been derived using computer simulation tools, in particular Computational Fluid Dynamics (CFD) so that the use of CFD is included in the review. A detailed review including performance benchmarking, time line evolution, challenges and proposals, as well as manufacturing issues is discussed.Ministerio de Ciencia, Innovación y Universidades ENE2017-91159-EXPMinisterio de Economía y Competitividad UNSE15-CE296

Magnetic Field scaling of Relaxation curves in Small Particle Systems

We study the effects of the magnetic field on the relaxation of the magnetization of small monodomain non-interacting particles with random orientations and distribution of anisotropy constants. Starting from a master equation, we build up an expression for the time dependence of the magnetization which takes into account thermal activation only over barriers separating energy minima, which, in our model, can be computed exactly from analytical expressions. Numerical calculations of the relaxation curves for different distribution widths, and under different magnetic fields H and temperatures T, have been performed. We show how a \svar scaling of the curves, at different T and for a given H, can be carried out after proper normalization of the data to the equilibrium magnetization. The resulting master curves are shown to be closely related to what we call effective energy barrier distributions, which, in our model, can be computed exactly from analytical expressions. The concept of effective distribution serves us as a basis for finding a scaling variable to scale relaxation curves at different H and a given T, thus showing that the field dependence of energy barriers can be also extracted from relaxation measurements.Comment: 12 pages, 9 figures, submitted to Phys. Rev.

Ge(113) reconstruction stabilized by subsurface interstitials: An x-ray diffraction structure analysis

The three-dimensional atomic coordinates of the Ge(113)-(3×1) surface have been determined by analyzing in-plane and out-of-plane x-ray intensity data. Besides dimer and adatom motifs, which reduce the number of dangling bonds, a random distribution of subsurface interstitials has been identified. Subsurface interstitials relieve elastic stress and lower the energy of the electronic system. Together with the delicate balance between the energy gain due to reduction of dangling bonds and the energy costs due to induced strain this determines the nature of the (3×1) reconstruction of Ge(113)