Alan Lomax en Louisiane : les hauts et les bas d’un chercheur de terrain

Cet article ne prétend pas repenser ici le travail considérable de ceux qui ont récemment étudié la vie et l’oeuvre de John et d’Alan Lomax sur les plans national et international. Il se limite plutôt à l’impact des Lomax en Louisiane française, surtout d’Alan, personnage qui se montrait à la fois inspirant et intimidant, frustrant et fascinant. Pendant les années 1930, John et Alan Lomax ont parcouru ce pays dans le but de réaliser des enregistrements de musique traditionnelle pour la Library of Congress. Leurs enregistrements sont devenus la base de l’Archive of Folk Song à la Library of Congress, véritable bijou de la musique traditionnelle des États-Unis. On dit d’Alan Lomax que ses observations étaient brillantes, tandis que ses interprétations passaient quelquefois à côté de la question. L’exposé ne cherche ni à glorifier ni à avilir, mais à reconnaître dûment le mérite et la critique dans la mesure où ils s’appliquent.This article does not presume to reconsider the extensive efforts of those who have recently studied the lives and work of John and Alan Lomax on the national and international scenes. Rather, it is limited to the impact of the Lomaxes in French Louisiana, especially that of Alan, who was variantly inspiring and intimidating, frustrating and fascinating. During the 1930s, John and Alan Lomax traveled across this country recording traditional music for the Library of Congress. Their recordings became the basis for the Library’s Archive of Folk Song, a veritable treasure of America’s traditional music. It could be said of Alan that his observations were brilliant, while his interpretations were sometimes off the mark. This article seeks neither to glorify nor to vilify, only to give credit and critique where they are due

Calibrating mars orbiter laser altimeter pulse widths at mars science laboratory candidate landing sites

Accurate estimates of surface roughness allow quantitative comparisons between planetary terrains. These comparisons enable us to improve our understanding of commonly occurring surface processes, and develop a more complete analysis of candidate landing and roving sites. A (secondary) science goal of the Mars Orbiter Laser Altimeter was to map surface roughness within the laser footprint using the backscatter pulse-widths of individual pulses, at finer scales than can be derived from the elevation profiles. On arrival at the surface, these pulses are thought to have diverged to between 70 and 170 m, corresponding to surface roughness estimates at 35 and 70 m baselines respectively; however, the true baseline and relationship remains unknown. This work compares the Mars Orbiter Laser Altimeter pulse-widths to surface roughness estimates at various baselines from high-resolution digital terrain models at the final four candidate landing sites of Mars Science Laboratory. The objective was to determine the true baseline at which surface roughness can be estimated, and the relationship between surface roughness and the pulse-widths, to improve the reliability of current global surface roughness estimates from pulse-width maps. The results seem to indicate that pulse-widths from individual shots are an unreliable indicator of surface roughness, and instead, the pulse-widths should be downsampled to indicate regional roughness, with the Slope-Corrected pulse-width dataset performing best. Where Rough Patches are spatially large compared to the footprint of the pulse, pulse-widths can be used as an indicator of surface roughness at baselines of 150 to 300 m; where these patches are spatially small, as observed at Mawrth Vallis, pulse-widths show no correlation to surface roughness. This suggests that a more complex relationship exists, with varying correlations observed, which appear dependent on the distribution of roughness across the sites

Le plateau de Brie à Fontaine-le-Port : géologie, géomorphologie, hydrologie et aménagement du territoire.

Guide géologique pour une excursion sur la vallée de la Seine. sortie géologique du dimanche 21 novembre 2010.Guide géologique pour une excursion sur la vallée de la Seine

Miocene siliciclastic deposits of Naxos Island: Geodynamic and environmental implications for the evolution of the southern Aegean Sea (Greece)

An interdisciplinary study has been carried out on Naxos Island, located in the southern Aegean Sea (Greece), which shows Miocene geodynamic and environmental changes in a classic example of a collapsing orogen. Early to Mid-Miocene siliciclastic deposits on Naxos have been shed from an uplifting mountainous realm in the south, which included a patchwork of at least four source terrains of different thermal histories.Petrography of pebbles suggests that the source units formed part of a passivecontinental margin succession (external Pelagonian unit), and an ophiolite succession mainly of deep-water cherts and limestones deposited on basalt substratum (Pindos unit). The continental margin source contributed rounded zircon crystals of Late Jurassic to Early Cretaceous age and broadly scattering Paleozoic zircon fission-track cooling ages. A distal pebble assemblage of Paleogene shallow-water carbonates passing into flysch-like, mixed calcarenitic and siliciclastic components with volcanic arc components is subordinately present. High-grade metamorphic components from the nearby metamorphic core complex are not present. The depositional evolution reflects increasing relief and, in some parts, a fluvial succession with rhythmic channel deposition, possibly due to runoff variability forced by orbital cyclicity. Upsection, the depositional trend indicates increasing seasonality and decreasing humidity in the source region. The Miocene sedimentary succession has been deposited on an ophiolite nappe. Juxtaposition of this ophiolite nappe occurred as an extensional allochthon during large-scale extension in the Aegean region at the margins of an exhuming metamorphic core complex

The Phenomenology of Decision Making

It is becoming apparent in modern cognitive science that the lack of knowledge about human experiential landscape implies the loss of a very important element, perhaps the very essence. Consequently, a rather new area of research has emerged recently: an attempt at a systematic observation and study of experience. This is the so-called phenomenologically inspired research (or just phenomenological research). Part of this article aims to present this new area of research - it describes the common fundaments of the field and some of its characteristic methodological derivates, relating them to the possibility of studying decision making from the first-person point-of-view, i.e. decision making as an experiential phenomenon (and not as a neurological or behavioural process). The article also presents some of the findings phenomenological studies have led to and some theoretical reflexions encouraged by these insights.experience, experiencing, phenomenology, phenomenological research, reason, first-person

Surface networks

© Copyright CASA, UCL. The desire to understand and exploit the structure of continuous surfaces is common to researchers in a range of disciplines. Few examples of the varied surfaces forming an integral part of modern subjects include terrain, population density, surface atmospheric pressure, physico-chemical surfaces, computer graphics, and metrological surfaces. The focus of the work here is a group of data structures called Surface Networks, which abstract 2-dimensional surfaces by storing only the most important (also called fundamental, critical or surface-specific) points and lines in the surfaces. Surface networks are intelligent and “natural ” data structures because they store a surface as a framework of “surface ” elements unlike the DEM or TIN data structures. This report presents an overview of the previous works and the ideas being developed by the authors of this report. The research on surface networks has fou

Stories from the walking library

From August 17 to September 17, 2012, Deirdre Heddon and Misha Myers created and carried a Walking Library, made for the Sideways Arts Festival. Sideways, a festival ‘in the open' and 'on the go', aimed to connect ecology and culture through using the 'slow ways' or ‘slow paths’ of Flanders. The Walking Library was comprised of more than 90 books suggested as books ‘good to take for a walk’ and functioned as a mobile library for Sideways’ artists and public participants. In addition to carrying a curated stock, the Library offered a peripatetic reading and writing group. Drawing on the Library’s resources and the experience of reading, writing and walking one’s way across Belgium, Heddon and Myers consider how reading in situ affects the experience of the journey and the experience of walking; how journeying affects the experience of reading; how reading affects the experience of writing; and how a walk, as a space of knowledge production, is written and read

Les Barrios de Ranchos à Caracas: une image spatiale des inégalités

International audienceLes bidonvilles sont devenus une caractéristique essentielle de la crise globale de surpopulation. L’avenir des villes dans les pays en voie de développement comportera une croissance de la population. « Au moins un quart de l’explosion démographique du prochain tiers monde sera due aux communautés informelles. Deux milliards de personnes vivront dans les bidonvilles en 2030 ou 2040, chiffre colossal, presque incompréhensible (...). La pauvreté urbaine du monde pourrait atteindre 45 à 50 % de la population urbaine totale » (Mike Davis, 2006).Caracas a subi un rapide et dramatique processus d’urbanisation dans lequel la modernisation volontaire et la planification urbaine proposée ne sont pas parvenues à donner de la rationalité à sa croissance. Notre imaginaire la voit entourée de hautes montagnes, enveloppée par sa végétation luxuriante, laquelle masque bon nombre de ses problèmes sociaux et architectoniques (Imbesi et Vila, 1995).Comment développer la recherche sur les thématiques des barrios ou bidonvilles vénézuéliens ? La nécessité d'étudier ces espaces informels est de plus en plus importante, au regard de leur croissance exponentielle et incontrôlable. Comprendre les effets de cette prolifération et de cette expansion sur les êtres humains (ou sur les sociétés) et l'environnement est devenu essentiel. L'idée d'étudier l'espace public dans les « barrios » de Caracas est née lors d'une première mission dans les quartiers informels de Mathare à Nairobi, puis d’une seconde, dans la Cité des Morts au Caire. À ces occasions, j’ai pu « cartographier » les aspects informels présents dans les quartiers spontanés. Il n’existe pas de meilleur moyen de comprendre une ville que lorsque l’on vit en présence de l’absence. Ce n’est de loin pas une question de nostalgie, mais un pacte secret qui se crée avec celle-ci. La distance avec la ville où j’ai grandi m’a permis de comprendre et d’individualiser les logiques internes à la ville informelle. Tout cela s’accompagne de mes expériences de travail dans le cadre de la coopération pour le développement au Caire, à Nairobi et à Haïti. L’éloignement de Caracas m’a conduite à observer d’autres réalités qui m’ont permis de comprendre les dynamiques des barrios à Caracas.À cet égard il est important de concevoir une recherche multidisciplinaire qui ne comprend pas seulement les domaines purement urbains. La ville informelle est potentiellement une ressource qui peut être convertie en projet de développement, mais seulement si les techniques d'analyse utilisées abordent tous ces aspects. L'étude devrait alors comporter différents points de vue pour comprendre l'espace urbain et pour cela, s’appuyer sur des disciplines telles que la sociologie, l'anthropologie, l’ethnographie, la photographie et l'agriculture. Le « mapping » ou cartographie multicritères est important pour l’analyse des rapports et des aspects urbains de la ville informelle, parce qu'elle comprend la signalisation cartographique des réalités urbaines informelles (commerces, vergers, maisons, etc.) qui peuvent être relevées par l'examen physique (à travers de la marche), sensible (entretiens) et architecturale (cartographie). Les inégalités et les couches les plus pauvres de Caracas doivent être « cartographiés » en prenant en compte le component sensible de la ville informelle, les aspects subjectifs