4,218 research outputs found
NodeTrix: Hybrid Representation for Analyzing Social Networks
The need to visualize large social networks is growing as hardware
capabilities make analyzing large networks feasible and many new data sets
become available. Unfortunately, the visualizations in existing systems do not
satisfactorily answer the basic dilemma of being readable both for the global
structure of the network and also for detailed analysis of local communities.
To address this problem, we present NodeTrix, a hybrid representation for
networks that combines the advantages of two traditional representations:
node-link diagrams are used to show the global structure of a network, while
arbitrary portions of the network can be shown as adjacency matrices to better
support the analysis of communities. A key contribution is a set of interaction
techniques. These allow analysts to create a NodeTrix visualization by dragging
selections from either a node-link or a matrix, flexibly manipulate the
NodeTrix representation to explore the dataset, and create meaningful summary
visualizations of their findings. Finally, we present a case study applying
NodeTrix to the analysis of the InfoVis 2004 coauthorship dataset to illustrate
the capabilities of NodeTrix as both an exploration tool and an effective means
of communicating results
Numerical Model for Oxide Scale Growth with Explicit Treatment of Vacancy Fluxes
In the framework of research on behaviour of nuclear waste containers, to evaluate the effects of possible evolution of experimental conditions, as well as evolution of parameters controlling oxidation rate during long-term interim storage, a numerical model has been developed in order to take into account non-stationary states. To anticipate effects like cold working of the metal on the scale growth kinetics and risks of scale detachment by over saturation of vacancies at the metal/oxide interface in the course of scale growth, the model is based on the calculation of chemical species, but also vacancies profiles evolution in the oxide and the metal following a simple time integration. An original numerical treatment is proposed to easily describe elimination of vacancies by introducing sink strength in the metal. The first calculations are presented and discussed
Low Temperature Oxidation of pure Iron : Growth kinetics and scale Morphologies
Isothermal oxidation of pure iron has been performed in air at atmospheric pressure between 260°C and 500°C. Growth kinetics are accurately analysed and scale morphologies are investigated by SEM and TEM observations. The calculation of the variations of the parabolic rate constant kp with scale thickness allows a better understanding of scale growth mechanisms involved at this intermediate temperature range, which have been poorly investigated up to now. These results are discussed with the objective of long term behaviour for long term interim storage of some nuclear waste containers
Market Power in Direct Marketing of Fresh Produce: Community Supported Agriculture Farms
CSA farms establish a loyal customer base and, potentially, market power. A new empirical industrial organization (NEIO) approach and survey data from Northeast CSA farms are used to determine whether CSA farms have market power and the extent to which they exercise their market power. Results suggest CSA farms exert about two percent of their potential monopoly power.Community Supported Agriculture; New Empirical Industrial Organization; Market Power; Fresh Produce; Organic Agriculture
Chemical Evolution in the Substrate due to oxidation: A Numerical Model with Explicit Treatment of Vacancy Fluxes
To get a better understanding of oxidation behavior of Ni-base alloys in PWR primary water, a numerical model for oxide scale growth has been developed. The final aim of the model is to estimate the effects of possible changes of experimental conditions. Hence, our model has not been restricted by the classical hypothesis of quasi-steady state and can consider transient stages. The model calculates the chemical species concentration profiles, but also the vacancy concentration profiles evolution in the oxide and in the metal as a function of time. It treats the elimination of the possible supersaturated vacancies formed at the metal/oxide interface by introducing a dislocation density at the interface and in the metal bulk. This latter density can be related to the cold-working state. Its effect on the vacancy profile evolution is studied in the case of a pure metal. Eventually an extension of the present model to the oxidation of Ni-base alloys is discussed regarding a recent vacancy diffusion model adjusted on Ni-base alloys
JEAN·LOUlS BAUDOUIN, La responsabilitĂ© civile dĂ©lictuelle, 3e Ă©dition, Cowansville, Les Ăditions Yvon Blais Inc., 1990, 838 pages, ISBN 2·89073·735·7
Subjective social class has a bad name, but predicts life chances well
Over the last decades, the study of subjective class has been eclipsed by research on objective class. The recurrent mismatch between subjective and objective class has led to the common wisdom that self-reported class is a poor measure of peopleâs life chances. This article questions this common wisdom. Based on ISSP 2009 and 2019, it shows for 55 country surveys that a pre-coded question on subjective class accounts for more variance in life chances â income and wealth â than various measures of objective class. Subjective class predicts individual income equally well as does objective class, but is a much better predictor of household income and wealth. It takes the two measures of respondentsâ and partnersâ objective class to match the variance explained in household income by a single measure of subjective class. In contexts of limited survey space and interview time, subjective class is an excellent indicator of peopleâs material situation
Secuestro corneal felino : estudio retrospectivo de 17 casos (1994-2004)
Se describe la incidencia y manejo clĂnico de 17 casos de secuestro corneal en una poblaciĂłn de 197 gatos atendidos. Se utilizaron diferentes tratamientos mĂ©dicos en casi la mitad de los casos, y cirugĂa en el resto. La mayorĂa de los casos quirĂșrgicos evolucionaron de manera aceptables.
Lâintervention syndicale : facteur de preÌvention des ineÌgaliteÌs dâacceÌs aÌ lâemploi ?
Si lâaction des confeÌdeÌrations syndicales a contribueÌ aÌ la concreÌtisation conventionnelle et eÌtatique du principe de non-discrimination, en revanche, les syndicats ne font du processus de recrutement que rarement un objet de revendication et de neÌgociation. Lâobservation de la deÌfinition et des pratiques de recrutement que nous avons opeÌreÌe sur vingt sites, les entretiens individuels conduits aupreÌs de sept syndicalistes et lâentretien collectif avec un groupe intersyndical teÌmoignent sans ambiguiÌteÌs de lâeÌloignement des syndicalistes de la probleÌmatique du recrutement. Les criteÌres ou les pratiques de recrutement ne font gueÌre lâobjet dâune attention particulieÌre des militants. Ils ne sont quâexceptionnellement aÌ lâordre du jour des reÌunions des sections dâentreprise. Or comment preÌvenir les discriminations aÌ lâembauche sans intervenir sur la deÌfinition des pratiques et des criteÌres de recrutement ? Lâintervention syndicale dans la pratique et la deÌfinition des criteÌres de recrutement renvoie donc aÌ la question de la deÌfinition de la preÌvention des ineÌgaliteÌs dâacceÌs aÌ lâemploi comme un des objectifs prioritaires de lâaction syndicale. Il nâappartient pas au chercheur de porter une reÌponse aÌ cette question meÌme si, aÌ titre personnel, il peut avoir un avis. In fine, cette deÌcision releÌve de la strateÌgie de lâorganisation syndicale. Le roÌle du chercheur est plus humblement dâen eÌclairer les enjeux en proposant cinq criteÌres dâanalyse du contexte : [1] la graviteÌ des discriminations aÌ lâembauche, [2] leur freÌquence, [3] leur impact socio-eÌconomique, [4] leur perception sociale et [5] lâexistence de possibiliteÌs dâintervenir (3)
Observation des pratiques et des critĂšres de recrutement. Le recrutement : un objet flou ?
Alors quâil est un des principaux opeÌrateurs de mobilisation de la main dâĆuvre pour les entreprises ainsi quâun des facteurs deÌterminants des parcours professionnels et personnels, le processus de recrutement reste un objet relativement meÌconnu.Si une abondante litteÌrature propose de « bonnes » meÌthodes, les investigations scientifiques sont plus rares. Dans le cadre dâun travail preÌparatoire aÌ lâenqueÌte Offre dâemploi et recrutement, HeÌleÌne Garner en conclusion de la survey des eÌtudes et recherches reÌaliseÌes sur le theÌme du recrutement souligne un reÌel besoin en termes de connaissances sur ce quâest un recrutement, son deÌroulement, ses modaliteÌs (1). De lâexamen attentif des recherches en cours, se deÌgagent neÌanmoins quatre hypotheÌses robustes aÌ meÌme de constituer le point de deÌpart de ce travail :âą le recrutement est un processus diffeÌrencieÌ en fonction du contexte eÌconomique, du secteur professionnel, de la taille de lâentreprise, du niveau de qualification et du statut juridique du poste aÌ pourvoir ;âą comme deÌcision, le recrutement est un processus caracteÌriseÌ par des rationaliteÌs multiples et contradictoires. AÌ ce titre, lâembauche est une deÌcision multicriteÌre, mais une deÌcision sensible aux effets dâimpression, de perception et dâinteractions entre le recruteur et le recruteÌ ;âą comme deÌcision, le recrutement est un objet flou. Câest-aÌ-dire un objet dont les contours et les frontieÌres [le poids des criteÌres de seÌlection par exemple] varient dâun contributeur aÌ lâautre en fonction de sa place et de son roÌle dans le processus en actes ;âą les ineÌgaliteÌs dâacceÌs aÌ lâemploi ne sont pas seulement le produit de strateÌgies deÌlibeÌreÌes [discrimination intentionnelle], mais aussi celui de logiques floues et partiellement inconscientes.Dans le cadre du questionnement geÌneÌral de la recherche prĂ©sentĂ©e ici, lâobjectif est de circonscrire le processus de recrutement en tirant toutes les conseÌquences formelles et meÌthodologiques de sa deÌfinition comme objet flou.(1) Garner H. (2004), Survey des eÌtudes et recherches reÌaliseÌes sur le theÌme du recrutement : travail preÌparatoire aÌ l'enqueÌte Offre d'emploi et recrutement, Convention Dares-Cergor
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