Les mousses fragiles font aujourd'hui partie des nouveaux matériaux très performants dont le procédé de fabrication permet un contrôle précis de la microstructure finale. De nouveaux débouchés apparaissent dans des applications structurales (absorption de choc, allègement des structures) en raison de leur excellente tenue mécanique alliée à une grande légèreté. Dans les travaux réalisés dans le cadre de cette thèse, une mousse carbone à cellules ouvertes a été étudiée dans le but d'être utilisée pour assurer la protection des capots de protection d'emballages. Le comportement mécanique en compression a été caractérisé sous des sollicitations uniaxiales et multiaxiales. La surface de charge de la mousse ainsi que son évolution au cours du chargement ont été identifiés. Les principales propriétés mécaniques ont été évaluées et certaines d'entre elles ont été corrélées avec celles prédites par le modèle micro-mécanique de Gibson et Ashby développé pour les mousses fragiles. Grâce aux observations post-mortem sous microscope électronique à balayage et en micro-tomographie aux rayons X, les mécanismes de déformation et d'absorption d'énergie ont été également caractérisés. Pour modéliser le comportement multiaxial en compression de la mousse carbone, considérée comme un milieu continu homogène et isotrope, le modèle de Deshpande et Fleck (DF) a été adopté et adapté. Ce modèle a été implanté dans le code éléments finis LS-DYNA. Il a été identifié et validé sur l'ensemble des essais triaxiaux disponibles ainsi que sur des essais d'écrasement de mini-structure. Le comportement macroscopique global, obtenu à l'aide de simulations numériques, est prédit de manière satisfaisante. Il sera amélioré par la suite pour prendre en compte certains aspects non décrits actuellement. / Due to improvements in the manufacturing process that allow a better control of their microstructure, brittle foams are now part of the new efficient materials. New markets in the field of structural applications open up thanks to their excellent mechanical properties combined with light weight.In this study, a carbon foam with open cells has been studied in order to be used as shock absorber in packagings. Its compressive mechanical behavior has been characterized under various uniaxial and multiaxial loadings. The carbon foam yield surface and its evolution during loading have been identified. The main mechanical properties have been evaluated and some of them have been correlated with those predicted by the Gibson and Ashby micromechanical model. The mechanisms of deformation and the energy absorption have been studied using post-mortem observations by scanning electron microscopy (SEM) and X-Ray microtomography.The Deshpande and Fleck model (DF) has been adopted and slightly modified to model the compressive multiaxial behavior of the carbon foam. The latter is considered as an homogeneous continuum medium. The constitutive equations have been implemented in the finite element code LS-DYNA via a Umat routine. The model parameters have been identified and the model estimations validated on available triaxial tests as well as on crushing tests made on micro-structures. Numerical simulations are relevant on predicting the global macroscopic behavior. Nevertheless, the mechanical model needs to be improved to better account for some phenomena not currently described.

No description available.

No description available.

[pt] A proposta dessa dissertação é analisar a existência ou não de um discurso alternativo por parte do governo brasileiro frente ao discurso tradicional sobre Estados falidos. Para realizar esse trabalho partimos de uma análise do discurso tradicionalmente usado, para entender como ele é constituído, quais as palavras chaves que o formam e as implicações que ele traz inerente ao seu conteúdo. Na tentativa de observar a existência ou não de um discurso alternativo por parte do Estado brasileiro, analisaremos a posição brasileira perante dois casos com os quais o Brasil teve amplo envolvimento: Haiti e Guiné Bissau. A partir de tais casos buscaremos entender como esse discurso alternativo é constituído, como e onde ele se diferencia do discurso tradicional. Por fim tentaremos observar quais as consequências esse discurso alternativo pode prover aos ditos Estados falidos. / [en] The purpose of this dissertation is to analyze the existence or not of an alternative discourse by the Brazilian government against the traditional discourse on failed States. To accomplish this work we start from an analysis of the traditionally used discourse to understand how it is made, what are the key words that form it and the implications it brings inherent to its content. In an attempt to observe the existence or nor of an alternative discourse by the Brazilian State, we will analyze the Brazilian position relative to two cases which Brazil had an extensive involvement: Haiti and Guinea Bissau. Starting from these two cases we will try to understand how this alternative discourse is constituted, how and where it differs from the traditional discourse. Finally we will try to observe what consequences this alternative discourse can provide to the so called failed States.

Grâce aux progrès de la génétique moléculaire qui ont permis d’identifier de nouveaux gènes de déficience intellectuelle liée à l’X, il nous a été possible de travailler sur des groupes homogènes de malades présentant une mutation dans le même gène. Nous avons d’une part, pu mettre en évidence un dysfonctionnement du circuit cérébello-thalamo-préfrontal grâce à une étude en IRM morphométrique réalisée chez des patients ayant une mutation dans le gène Rab-GDI. D’autre part, nous avons identifié un phénotype tout à fait spécifique lié aux mutations du gène ARX, tant clinique que neuropsychologique, et cinématique, associant une atteinte très particulière de la motricité distale des membres supérieurs et du langage. La préhension des patients est pathognomonique, avec une préférence pour la pince pouce-majeur, une difficulté accrue pour l’utilisation du bord cubital de la main, et un trouble de la pronosupination. Sur le plan neuroanatomique, il existe une diminution de volume des noyaux gris centraux et des épaisseurs corticales des régions contrôlant la motricité, bien corrélées au paramètres de cinématique. Enfin, nous avons exploré les stratégies de raisonnement des patients déficients intellectuels atteints du syndrome de l’X fragile, d’une mutation du gène ARX ou de trisomie 21 en élaborant un paradigme de raisonnement visuel analogique issu des matrices de Raven. Nous en avons établi la trajectoire développementale. Les stratégies utilisées par les patients (étude en eyetracking) sont différentes de celles des contrôles y compris de même âge mental, avec un défaut d’inhibition majeur, encore plus franc chez les patients X fragiles que ceux porteurs de trisomie 21 / Thanks to progress in molecular genetics, that allowed identification of new genes responsible for X linked intellectual disability, we studied on homogeneous groups of patients presenting with a mutation in one or the other gene. In the first section, we showed dysfunction of cerebello-thalamo-prefrontal networks, thanks to morphological MRI study performed on patients with a mutation in the Rab-GDI gene. In the second section, we highlighted a very specific phenotype related to ARX gene mutations, clinically, neuropsychologically, and kinematically, with a very peculiar impairment of upper limbs distal motricity, and language disorder. Patients hand-grip is pathognomonic, with a preference for the middle finger instead of the index for the grip of object, major impairment of fourth finger use, and lack of pronation movements. Neuroimaging study showed decreased volume of basal ganglia, and cortical thickness of motor regions, well correlated to kinematic parameters. In the third section, we explored reasoning strategies in three groups of patients with intellectual deficiency: fragile X, ARX mutated and Down syndrome patients and controls (both chronological and mental age-matched subjects). We notably elaborated a visual analogical reasoning paradigm, inspired from Raven’s matrices. We established a developmental trajectory of this paradigm. The strategy used by patients (eyetracking study) was different from the one used by controls, with a huge lack of inhibition, even greater for fragile X patients than for Down syndrome patients

The current work has as its general theme the solutions-locations found by the poorest part of the population of Brazilian cities in terms of housing. It specifically addresses the appropriation of environmentally sensitive areas in urban locations for that purpose, (more precisely, the edges of urban water bodies), and the conflicts (social, environmental and, consequently, political) that surround such situations. The research is a case study which has as its empirical focus the situation of the human settlements on the banks of the Mundaú Lagoon in Maceió, capital of Alagoas, and takes as its starting point the hypothesis that "the urban environmental issue is primarily a housing problem and a problem of the adoption of policies that will facilitate the access of the majority of the population to adequate housing". (Martins 2002, p.126) The discussion focuses initially on the relationship between the process of urbanization and poverty in Brazil, contextualizing the settlements of the poorest part of the population of Brazilian cities and specifically of the city of Maceió. This is followed by a discussion of the socio-environmental dimension of human settlements in environmentally sensitive areas, especially those located on the shores of Mundaú Lagoon. Later, we discuss public policies for the promotion of housing for the poorest in Brazilian cities, with emphasis on those policies which are related to the human settlements on the banks of Mundaú Lagoon, and point out the conflicts of interest that permeate the decisions of public authorities, especially those with respect to the use and occupation of environmentally fragile areas in the urban space. The work leads us to understand that the phenomenon of precarious human settlements in environmentally fragile areas is the result of the reproductive processes of the socio-spatial inequalities inherent in the reproduction of urban space in Brazil. In this manner we come to see the urban environmental issue as a problem that stems from the difficulties of access to adequate housing of most of the population. While this access is determined by the income of the population the place of the poor will be a place ever more excluded from the benefits of the city. / Fundação de Amparo a Pesquisa do Estado de Alagoas / O presente trabalho tem por tema geral as soluções-localizações encontradas pela população mais pobre nas cidades brasileiras para moradia. Aborda-se especificamente a apropriação de áreas ambientalmente frágeis em meios urbanos para aquele fim, mais precisamente, as margens de corpos d água urbanas, bem como os conflitos (sociais, ambientais e, conseqüentemente, políticos) que envolvem tais situações. A pesquisa consiste em um estudo de caso, que tem por objeto empírico a situação dos assentamentos humanos às margens da lagoa Mundaú, em Maceió, capital de Alagoas e parte da hipótese de que a questão ambiental urbana é antes de tudo um problema de moradia e de adoção de políticas que possibilite o acesso da maioria da população a uma moradia adequada. (MARTINS 2002, p.126) A discussão trata inicialmente da relação entre o processo de urbanização e a pobreza no Brasil, contextualizando os assentamentos da população mais pobres nas cidades brasileiras e especificamente na cidade de Maceió. Em seguida, discute-se a dimensão socioambiental dos assentamentos humanos em áreas ambientalmente frágeis, mas especificamente, daqueles localizados às margens da Lagoa Mundaú. Posteriormente, abordam-se as políticas públicas de promoção de habitação para os mais pobres nas cidades brasileiras, enfatizando-se aquelas referentes aos assentamentos humanos às margens da lagoa Mundaú e aponta-se para os conflitos de interesse que permeiam as decisões do poder público, especialmente, quando se referem ao uso e ocupação de áreas ambientalmente frágeis no espaço urbano. O trabalho leva a compreensão de que o fenômeno dos assentamentos humanos precários em áreas ambientalmente frágeis é fruto dos processos de reprodução das desigualdades sócioespaciais inerente à reprodução do espaço urbano no Brasil. Desse modo, a questão ambiental urbana aparece como um problema decorrente das dificuldades de acesso à moradia adequada da maior parte da população. Enquanto esse acesso estiver condicionado à renda da população, cada vez mais, a localização dos pobres consistirá em locais excluídos dos benefícios da cidade.

Face à l'uniformisation marchande du monde, aux épreuves de synthèses technologiques et industrielles, aux discrédits de la nature méthodiquement consentis, à l'asservissement machinique de notre sensibilité, l'homme apparaît, comme les artefacts qu'il a créés, semblable à une entité idéalisée et artificielle, inadaptée à son milieu. Comment ré-envisager alors nos modalités de créativité et de générativité au-delà du paradigme humaniste finissant, par-delà cette crise multiple de la pensée et de l'identité, de l'espace et de la représentation ? La conversion des principes métaphysiques et substantialistes nous oriente auprès de sentirs transindividuels, vers un devenir non humain de l'être-par-delà-le-sujet. Penser les valences entre intelligibilité et sensibilité, les médiances entre être technique et naturel, les transjections entre entendement et imagination suppose de reconsidérer la nature de l'être au-delà de ses forces de détermination, dans la puissance de sa vulnérabilité. Cet essai d'esthétique sur la créativité spatiale contemporaine s'attache à établir à l'aune de la révolution numérique une poïétique géosensible, transverse et trilogique, qui questionne conjointement les processus actuels de création artistique, de conception architecturale et de conceptualisation philosophique. Il s'accorde à penser l'acte créatif à partir du concept de dispositif géosensible, application spatiale du devenir-frémissant et de ses modalités que sont les fragmentations, les micro-hétérogénéisations et les fluences. / Faced with the mercantile globalisation of the world, the processes of technological and industrial syntheses, the discreditation of nature which has been methodologically consented to, and the mechanical subservience of our sensibilities, human beings appear, like the artefacts they have created, like idealised and artificial entities, ill-adapted to their surrounding world.How can we then re-envisage our creative and generative modalities beyond the humanist paradigm which is drawing to an end, outside this multiple crisis of identity and thought, and of space and representation. The conversion of metaphysical and substantialist principles orients us towards transindividual feelings for a post-human becoming of the being-outside-the-subject. Thinking the valencies between intelligibility and sensibility, the mediancies between technical and natural being, the transjections between comprehension and imagination, postulates reconsidering the nature of the being beyond its powers of determination, in the strength of its vulnerability.This essay on the aesthetics of contemporary spatial creativity seeks to establish, in light of the digital revolution, a geosensible poïetics, transversal and trilogical, which conjointly questions the current processes of artistic creation, architectural conception, and philosophical conceptualisation. It seeks to think the creative act from the point of view of the concept of the geosensible device, a spatial application of a becoming-trembling, and of its modalities which are fragmentations, micro-heterogenisations, and fluences.

La trisomie 21 (T21), le Syndrome X Fragile (SXF), la Sclérose tubéreuse de Bourneville (STB) et les mutations SYNGAP1 sont causés par des dysfonctionnements des voies moléculaires qui entraînent notamment un déséquilibre dans l’excitation et l’inhibition de l’activité neuronale qui aurait des impacts sur le développement et le fonctionnement du cerveau. Toutefois, il est difficile de faire le pont entre les déséquilibres moléculaires observés dans les modèles animaux et les particularités structurelles, fonctionnelles et cognitives observées dans ces syndromes chez l’humain. À notre connaissance, peu d’études ont comparé différents syndromes génétiques sur les processus sensoriels, l’apprentissage de base ou encore leurs caractéristiques comportementales en utilisant des paradigmes similaires et translationnels, permettant de mieux comprendre leurs particularités. Le premier volet de cette thèse vise à identifier si l’activité électroencéphalographique serait un biomarqueur adéquat représentant les altérations neurobiologiques tant des processus sensoriels que d’apprentissage chez les humains présentant ces syndromes. L’étude #1 avait comme objectif de décrire le traitement sensoriel auditif, comme il s’agit d’un processus élémentaire, et ce, chez les mutations SYNGAP1 qui représentent une condition génétique encore peu étudiée chez l’humain. Les résultats ont d’ailleurs permis d’identifier une diminution de la synchronisation de phase et une augmentation de la puissance dans la bande gamma qui distinguent cette condition génétique tant des participants sans DI que de la T21. Toujours dans l’esprit d’identifier des biomarqueurs électroencéphalographiques, mais cette fois au niveau d’un processus cognitif de base, l’étude #2 avait pour objectif de comparer tous ces syndromes dans un paradigme de suppression neuronale (SN) afin de vérifier la présence de SN et de comparer l’apprentissage de base chez ces populations. Les résultats ont identifiés que la T21 et le SXF présentaient tous les deux un patron de SN et que le SXF présentait relativement une plus forte habituation indiquant des particularités spécifiques selon les syndromes. Le deuxième volet, davantage clinique, permet de comparer les profils comportementaux associés au fonctionnement adaptatif entre les syndromes et à décrire les pistes d’intervention existantes. L’étude #3 a notamment mis en évidence que le QI et les symptômes de TDAH sont associés au fonctionnement adaptatif auprès de ces différents syndromes dont le SXF et la STB. Cet article a aussi permis de décrire les profils comportementaux de ces mêmes conditions en révélant davantage de difficultés rapportées chez les individus présentant un SXF, alors que la T21 présentait moins de particularités cliniques au niveau comportemental. Enfin, l’article #4 a mis en lumière diverses interventions utilisées auprès de la population présentant une DI notamment des stratégies cognitivo-comportementales et compensatoires. Cette thèse permet donc de dresser un portrait spécifique de ces syndromes génétiques concernant leur signature électrophysiologique lors du traitement sensoriel et de l’apprentissage ainsi que sur le plan des comorbidités comportementales et de leur relation avec le fonctionnement adaptatif, pour ensuite aborder les interventions actuelles en DI. Les diverses particularités identifiées à plusieurs niveaux ont permis de générer des suggestions pouvant guider certaines interventions futures. / Down syndrome (DS), Fragile X syndrome (FXS), Tuberous sclerosis complex (TSC) and SYNGAP1 mutations are caused by dysfunctions of the molecular pathways which lead among others to an imbalance in excitation and inhibition of the neuronal activity that would impact the brain development and its functioning. However, it is difficult to directly bridge the gap between the molecular imbalances observed in animal models with the structural, functional and cognitive characteristics observed in human with these syndromes. To our knowledge, few studies have compared those different genetic syndromes on sensory processing, basic learning or on their behavioural issues using similar and translational paradigms then allowing a better understanding of their specificities. The first part of this thesis aims to identify whether electroencephalographic activity would be an adequate biomarker representing neurobiological alterations both in sensory processing and learning in humans with these syndromes. The goal of study #1 was to describe auditory sensory processing, as a very first basic process, in SYNGAP1 mutations being a genetic condition still little studied in humans. Results showed a decrease in phase synchronization and an increase in the power of gamma band which distinguish this genetic condition both from participants without ID and from DS. Still in order to identify electroencephalographic biomarkers, but this time at a basic cognitive level, study #2 aimed to compare all these syndromes in a repetition suppression (RS) paradigm in order to observe the presence of RS and compare basic learning in these populations. The results identified a RS pattern in both DS and FXS. FXS also exhibited relatively higher habituation then indicating specific features according to the syndrome. The second part, addressing clinical aspects, permits to compare the behavioural profiles associated with adaptive functioning between syndromes and to describe existing interventions on ID population. Study #3 notably highlighted that IQ and ADHD symptoms are associated with adaptive functioning especially in FXS and TSC. This article also made it possible to describe the behavioural profiles of these syndromes, revealing more difficulties reported in individuals with FXS, while DS presented fewer behavioural issues. Finally, article #4 highlighted various interventions used with ID population, notably cognitive-behavioural and compensatory strategies. This thesis therefore makes it possible to gain a better understanding of these genetic syndromes concerning their electrophysiological signature during sensory processing and learning as well as in terms of behavioural comorbidities and their relationship with adaptive functioning, to then address current ID interventions. These different syndromic particularities identified at several levels made it possible to generate suggestions that could guide future interventions in this field.

The dissertation investigates the issues of image authentication and tamper localization after general image processing operations – blurring, sharpening, rotation and JPEG compression. The dissertation consists of four parts including Introduction, 4 chapters, Conclusions, References. The introduction reveals the investigated problem, importance of the thesis and the object of research and describes the purpose and tasks of the paper, research methodology, scientific novelty, the practical significance of results examined in the paper and defended statements. The introduction ends in presenting the author’s publications on the subject of the defended dissertation, offering the material of made presentations in conferences and defining the structure of the dissertation. Chapter 1 revises used literature, analyzes competitive methods. The devastating effect of blur/sharpen methods on digital image matrices is shown. General pixel-wise tamper localization methods are completely inefficient after such casual processing. Block-wise methods demonstrate some resistance against blurring/sharpening, but no tamper localization with the resolution of up to one pixel is possible. There is clearly a need for a method, able to locate damaged pixels despite general image processing operations such as blurring or sharpening. Chapter 2 defines theoretical foundation for the proposed method. It is shown that phase of Fourier transform demonstrates invariance against blurring or sharpening... [to full text] / Disertacijoje nagrinėjamos atvaizdų apsaugos – autentiškumo užtikrinimo ir pažeidimų radimo, po bendrųjų vaizdo apdorojimo procedūrų – blukinimo, ryškinimo, pasukimo ar JPEG suspaudimo – problemos. Disertaciją sudaro įvadas, keturi skyriai, rezultatų apibendrinimas, naudotos literatūros ir autoriaus publikacijų disertacijos tema sąrašai. Įvadiniame skyriuje aptariama tiriamoji problema, darbo aktualumas, aprašomas tyrimų objektas, formuluojamas darbo tikslas bei uždaviniai, aprašoma tyrimų metodika, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, ginamieji teiginiai. Įvado pabaigoje pristatomos disertacijos tema autoriaus paskelbtos publikacijos ir pranešimai konferencijose bei disertacijos struktūra. Pirmasis skyrius skirtas literatūros apžvalgai. Jame pateikta konkuruojančių metodų apžvalga. Parodomas globalus blukinimo/ryškinimo operacijų poveikis atvaizdo skaitmeninėms matricoms. Išsiaiškinama kodėl pikselių tikslumo metodai nėra atsparūs tokiam poveikiui. Kodėl blokiniai metodai demonstruoja dalinį atsparumą – bet jie nėra pajėgūs surasti vieno pažeisto pikselio. Parodomas aiškus poreikis metodo, tiek galinčio rasti pažeistus pikselius, tiek atsparaus bendroms vaizdo apdorojimo procedūroms, tokioms kaip blukinimas ar aštrinimas. Antrajame skyriuje pateiktas sukurto metodo teorinis pagrindimas. Įrodoma, kad Furjė fazė pasižymi atsparumu blukinimui ir ryškinimui. Tačiau iškyla sekanti problema dėl to, kad Furjė fazėje neįmanoma rasti konkretaus pikselio –... [toliau žr. visą tekstą]

Companies adopt codes of conduct to set minimum standards on ethical issues, minimums that suppliers must keep. Problems has been found by other researchers regarding suppliers motivation to comply to the code. This study develops a conceptual model for how motivation can be adjusted to different countries, depending on economic situation, politic stability and culture of the country.   Country-Adjusted Motivation is made  by shaping motivating in relation to the human need that dominates in the country and by using the national culture to colour motivation. The model is applied in the context of how to motivate suppliers to a code of conduct in different countries. The model Country-Adjusted Motivation could as well be applied to other multinational contexts, where strong motivation is needed.