972 resultados para Graph unification


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Valtion rajat ylittävät terveyspalvelut Euroopan unionissa sekä Euroopan unionin säädösten merkitys ja vaikutus erityisesti lääkejakeluun ja verenluovuttajille jaettavaan tiedotusaineistoon Valtion rajat ylittävä terveydenhuolto on suuren kiinnostuksen kohteena Euroopan unionissa. Resurssien hyödyntäminen parhaalla mahdollisella tavalla ja tiedon keskittäminen ovat tarpeen terveydenhuollon kustannusten alati noustessa. Terveydenhuoltopalvelut kuuluvat Euroopan sisämarkkinoiden vapaan liikkuvuuden piiriin. Euroopan unionilla ei ole kuitenkaan toimivaltaa säädellä terveydenhuoltojärjestelmiä, vaan sen mahdollisuudet ovat enimmäkseen kansanterveyden edistämisessä ja suojelussa, myös muilla toimialueilla kuin terveydenhuollossa. Tutkimuksen tavoitteena oli tutkia Euroopan unionin säädösten vaikutusta terveydenhuoltosektoriin, erityisesti valtion rajat ylittäviin terveydenhuoltopalveluihin. Erityiskohteena olivat lääkemääräyksen toimittaminen toisen Euroopan unionin jäsenmaan apteekista, resepti-lääkkeiden maahantuonti omaan henkilökohtaiseen käyttöön, sähköisen lääkemääräyksen käyttö kansallisesti ja mahdollisuudet sen käyttöön eri jäsenmaiden välillä, online-apteekkien soveltuvuus Euroopan unionin sisämarkkinoille sekä verenluovuttajille jaettavan tiedotusaineiston yhtenäistämistarve Euroopan unionin alueella. Tutkimuksen osa-alueiden aineisto koottiin vuosina 1999–2003, jolloin Euroopan unioniin kuului 15 jäsenmaata. Apteekit toimittivat useimmiten myös ei-kansalliset, toisessa Euroopan unionin jäsenmaassa annetut lääkemääräykset. Kaikki jäsenmaat rajoittivat lääkemääräyksen vaativien lääkkeiden maahantuontia. Rajoituksia oli maahantuontimäärissä ja -tavoissa. Lisäksi sairasvakuutuskorvausten saaminen ulkomailla lunastetuista reseptilääkkeistä oli hankalaa. Sähköiset lääkemääräykset olivat käytössä vain kahdessa maassa, mutta useissa maissa suunniteltiin niiden kokeilua. Standardit ja käyttöjärjestelmät olivat erilaisia eri maissa. Euroopan unionin alueelle on perustettu online-apteekkeja, joiden toiminta on kuitenkin vaatimatonta. Verenluovuttajille annettava tiedotusaineisto ei missään maassa täyttänyt veridirektiivin vaatimuksia. Tutkimuksen tulokset osoittivat kansallisten käytäntöjen eroavaisuuksien rajoittavan valtion rajat ylittäviä terveydenhuoltopalveluita. Vaikka Euroopan unionin tavoitteena ei ole yhtenäistää terveydenhuoltojärjestelmiä, on tarpeen arvioida uudelleen unionin ja jäsenmaiden välistä työnjakoa. Kansalliset terveydenhuoltojärjestelmät eivät ole erillään Euroopan sisämarkkinoista, jotka merkittävästi vaikuttavat terveydenhuoltoon.

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El 1736, Leonhard Euler va ser pioner en l'estudi de la teoria de grafs, i des de llavorsmúltiples autors com Kirchoff, Seymour, etc. continuaren amb l'estudi de la teoria i topologiade grafs. La teoria de xarxes, part de la teoria de grafs, també ha estat estudiada abastament.D'altra banda, la dinàmica de xarxes fou popularitzada per Dan Gillespie el 1977, en el qual proposà un algorisme que permet la simulació discreta i estocàstica d'un sistema de partícules, el qual és la base del treball ja que serveix per dur a terme les simulacions de processos sobre les xarxes complexes. El camp de l'anàlisi de la dinàmica de xarxes, de fet, és un campemergent en l'actualitat; comprèn tant l'anàlisi estadística com la utilització de simulacions persolucionar problemes de la mateixa dinàmica.Les xarxes complexes (xarxes de característiques complexes, sovint xarxes reals) també sónobjecte d'estudi de l'actualitat, sobretot a causa de l'aparició de les xarxes socials. S'han convertiten un paradigma per l'estudi de processos dinàmics en sistemes formats per molts componentsque interactuen entre si de manera molt homogèniaL'objectiu del treball és triple:1. Estudiar i entendre els conceptes bàsics i la topologia de les xarxes complexes, així comdiferents tipus de dinàmiques de processos sobre elles.2. Programar un simulador estocàstic en llenguatge C++ capaç de generar trajectòries mitjantçant l'algorisme de Gillespie tant pel model epidèmic com pel model de dinàmicad'enllaços amb reconnexió.3. Utilitzar el simulador tant per estudiar casos que ja han estat tractats en la literatura comcasos nous que no han estat tractats i que poden ser assimilables a xarxes reals com, perexemple, xarxes socials

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Diplomityön tavoitteena oli selvittää tandem-MAG-hitsausmenetelmän soveltuvuus isojen levylakanoiden valmistamiseen. Päätavoitteena oli selvittää suurimmat saavutettavat hitsausnopeudet sekä railonvalmistukselle asetettavat vaatimukset kahdella laivanrakennusteräksellä. Tutkimuksessa käytettiin omia hitsauskokeita ja liitokset testattiin luokitusseurojen vaatimusten mukaisesti. Selvitettiin myös syntyvät hitsausmuodonmuutokset sekä edut ja rajoitukset verrattuna laserhitsaukseen. Lisäksi laadittiin ei-synergiselle pulssihitsauslaitteistolle suuntaa-antava synergiakäyrä tätä sovellusta varten hitsauskokeiden perusteella. Tandem-MAG-hitsaus osoittautui erittäin kilpailukykyiseksi hitsausmenetelmäksi sovelluksessa. Magneettisen puhalluksen havaittiin olevan merkittävä häiriötekijä tällä menetelmällä hitsattaessa.

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Two graphs with adjacency matrices $\mathbf{A}$ and $\mathbf{B}$ are isomorphic if there exists a permutation matrix $\mathbf{P}$ for which the identity $\mathbf{P}^{\mathrm{T}} \mathbf{A} \mathbf{P} = \mathbf{B}$ holds. Multiplying through by $\mathbf{P}$ and relaxing the permutation matrix to a doubly stochastic matrix leads to the linear programming relaxation known as fractional isomorphism. We show that the levels of the Sherali--Adams (SA) hierarchy of linear programming relaxations applied to fractional isomorphism interleave in power with the levels of a well-known color-refinement heuristic for graph isomorphism called the Weisfeiler--Lehman algorithm, or, equivalently, with the levels of indistinguishability in a logic with counting quantifiers and a bounded number of variables. This tight connection has quite striking consequences. For example, it follows immediately from a deep result of Grohe in the context of logics with counting quantifiers that a fixed number of levels of SA suffice to determine isomorphism of planar and minor-free graphs. We also offer applications in both finite model theory and polyhedral combinatorics. First, we show that certain properties of graphs, such as that of having a flow circulation of a prescribed value, are definable in the infinitary logic with counting with a bounded number of variables. Second, we exploit a lower bound construction due to Cai, Fürer, and Immerman in the context of counting logics to give simple explicit instances that show that the SA relaxations of the vertex-cover and cut polytopes do not reach their integer hulls for up to $\Omega(n)$ levels, where $n$ is the number of vertices in the graph.

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Viimeisten vuosien aikana laajakaistaoperaattoreiden laajakaistaverkot ovat nopeiden ja kiinteähintaisten laajakaistaliittymien johdosta kasvaneet suuriksi kokonaisuuksiksi. Kokonaisuuksia hallitaan erilaisilla verkonhallintatyökaluilla. Verkonhallintatyökalut sisältävät suuren määrän eri tasoista tietoa laitteista ja laitteiden välisistä suhteista. Kokonaisuuksien hahmottaminen ilman tiedoista rakennettua kuvaa on vaikeaa ja hidasta. Laajakaistaverkon topologian visualisoinnissa muodostetaan kuva laitteista ja niiden välisistä suhteista. Visualisoitua kuvaa voidaan käyttää osana verkonhallintatyökalua, jolloin käyttäjälle muodostuu nopeasti näkymä verkon laitteista ja rakenteesta eli topologiasta. Visualisoinnissa kuvan piirto-ongelma täytyy muuttaa graafin piirto-ongelmaksi. Graafin piirto-ongelmassa verkon rakennetta käsitellään graafina, joka mahdollistaa kuvan muodostamisen automaattisia piirtomenetelmiä hyväksikäyttäen. Halutunlainen ulkoasu kuvalle muodostetaan automaattisilla piirtomenetelmillä, joilla laitteiden ja laitteiden välisten suhteiden esitystapoja voidaan muuttaa. Esitystavoilla voidaan muuttaa esimerkiksi laitteiden muotoa, väriä ja kokoa. Esitystapojen lisäksi piirtomenetelmien tärkein tehtävä on laskea laitteiden sijaintien koordinaattien arvot, jotka loppujen lopuksi määräävät koko kuvan rakenteen. Koordinaattien arvot lasketaan piirtoalgoritmeilla, joista voimiin perustuvat algoritmit sopivat parhaiten laajakaistaverkkojen laitteiden sijaintien laskemiseen. Tämän diplomityön käytännön työssä toteutettiin laajakaistaverkon topologian visualisointityökalu.

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Social interactions are a very important component in people"s lives. Social network analysis has become a common technique used to model and quantify the properties of social interactions. In this paper, we propose an integrated framework to explore the characteristics of a social network extracted from multimodal dyadic interactions. For our study, we used a set of videos belonging to New York Times" Blogging Heads opinion blog. The Social Network is represented as an oriented graph, whose directed links are determined by the Influence Model. The links" weights are a measure of the"influence" a person has over the other. The states of the Influence Model encode automatically extracted audio/visual features from our videos using state-of-the art algorithms. Our results are reported in terms of accuracy of audio/visual data fusion for speaker segmentation and centrality measures used to characterize the extracted social network.

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Les traités scientifiques ne font que depuis peu d'années l'objet d'études en histoire des sciences. Pourtant, ces traités ont énormément à apporter car ils renseignent sur la manière de raisonner des auteurs, ainsi que sur le développement d'une discipline. Dans ce travail de doctorat, différents traités des maladies du système nerveux ont été dépouillés, notamment le traité de Sémiologie des affections du système nerveux (1914) de Jules Dejerine (1849-1917). Ce traité a été analysé de trois manières différentes. Il a tout d'abord été comparé à une édition précédente publiée sous forme de chapitre (1901), révélant un large remodelage du contenu du traité, suggérant une évolution rapide de la discipline neurologique en l'espace de quelques années. Deuxièmement, l'analyse de la Sémiologie a permis de recréer un réseau de professionnels avec qui Jules Dejerine était en contact et, en parcourant les livres publiés par ces auteurs, il a été possible de décrire de quelle manière ces auteurs se citent mutuellement. Finalement, ces livres contiennent de nombreuses illustrations, qui sont associées à la notion de « preuve » : les auteurs utilisent des images sous forme de dessins, de photographies ou de schémas qui illustrent des patients ou des pièces anatomiques pour « montrer » la maladie ou la lésion. Chaque illustration a un rôle à jouer pour décrire la lésion, montrer la progression de la maladie et elle aide le médecin à poser le diagnostic. Grâce à ces trois axes de recherche, un traité devient un outil de travail dynamique, qui évolue au fil des rééditions, influencé par les critiques et commentaires retrouvés dans d'autres traités et articles, et par les progrès accomplis dans la discipline traitée. Des, passages et certaines images de l'ouvrage circulent également de traité en traité et véhiculent l'autorité de l'auteur de ces passages et images qui en viennent à représenter la maladie. Ce transfert d'images joue également un rôle dans la standardisation du diagnostic et dans l'unification de la neurologie à travers le monde occidental au début du XXe siècle, une période charnière pour l'histoire de la médecine. -- Au début du XXe siècle, la neurologie est une jeune spécialité médicale qui se développe rapidement. Les différents médecins publient des traités, communiquent entre eux et échangent leurs données. Un traité scientifique est un outil de travail dynamique qui évolue avec les rééditions et le développement d'une discipline. Ces ouvrages recèlent toutes sortes d'informations et leur analyse ne fait que depuis peu de temps l'objet d'études en histoire des sciences. Ces traités regorgent notamment d'illustrations qui sont associées à la notion de « preuve » : les auteurs utilisent des images sous forme de dessins, de photographies ou de schémas qui représentent des patients ou des pièces anatomiques afin de « montrer » la maladie ou la lésion. Chaque illustration a un rôle à jouer pour décrire la pathologie, montrer la progression de la maladie et elle aide le médecin à poser le diagnostic. Les auteurs des traités, qui viennent d'Europe et d'Amérique du Nord, se citent mutuellement, permettant au lecteur de recréer leur réseau de professionnels au niveau international. De plus, comme ces auteurs réutilisent les observations et les illustrations des autres, celles-ci circulent de traité en traité et en viennent à représenter la maladie. Ce transfert d'images joue également un rôle dans la standardisation du diagnostic et dans l'unification de la neurologie à travers le monde occidental au début du XXe siècle, une période charnière pour l'histoire de la médecine. -- Until recently, the study of textbooks has been neglected in the history of the sciences. However, textbooks can provide fruitful sources of information regarding the way authors work and the development of a particular discipline. This dissertation reviews editions of a single textbook, the Sémiologie des affections du système nerveux (1914) by Jules Dejerine (1849-1917). This textbook enabled the description of three axes of research. Firstly, by comparing the book to a first edition published as a chapter, one can acknowledge an extensive remodeling of the content of the book, suggesting a vast increase in knowledge over time. Secondly, by looking at the authors that Dejerine quotes repeatedly, it becomes possible to recreate his professional network, to review the works of these authors and to determine how they cross-reference each other. Thirdly, these textbooks contain numerous medical illustrations, which are linked with the concept of "proof;" the authors demonstrate a willingness to "show" the lesion or the pathology by publishing an image. Drawings, schematic representations, radiographies, or photographs of patients or of anatomical preparations all have their own purpose in describing the lesion and the progression of the disease. They assist in the diagnosis of the pathology. By looking at all of these aspects, it is therefore possible to conclude that a neurological textbook is a dynamic object that evolves through re-editions, comments and references found in other textbooks and by the circulations of parts of these books, such as the images. The illustrations also carry the author's authority, since their ongoing use claims that the work by the owner of the image has been endorsed by others. At the same time, it validates the borrowers' arguments. By using medical illustrations from different authors worldwide, the authors are also making a claim to a common language, to a similar way of examining patients, and about how much they depend on medical imagery to prove their points. In that sense, by focusing upon these textbooks, one can affirm that neurology already existed as a worldwide specialty at the turn of the twentieth century. Much more than mere accompaniments to the text, images were of paramount importance to the unification of neurology.

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The human auditory cortex comprises the supratemporal plane and large parts of the temporal and parietal convexities. We have investigated the relevant intrahemispheric cortico-cortical connections using in vivo DSI tractography combined with landmark-based registration, automatic cortical parcellation and whole-brain structural connection matrices in 20 right-handed male subjects. On the supratemporal plane, the pattern of connectivity was related to the architectonically defined early-stage auditory areas. It revealed a three-tier architecture characterized by a cascade of connections from the primary auditory cortex to six adjacent non-primary areas and from there to the superior temporal gyrus. Graph theory-driven analysis confirmed the cascade-like connectivity pattern and demonstrated a strong degree of segregation and hierarchy within early-stage auditory areas. Putative higher-order areas on the temporal and parietal convexities had more widely spread local connectivity and long-range connections with the prefrontal cortex; analysis of optimal community structure revealed five distinct modules in each hemisphere. The pattern of temporo-parieto-frontal connectivity was partially asymmetrical. In conclusion, the human early-stage auditory cortical connectivity, as revealed by in vivo DSI tractography, has strong similarities with that of non-human primates. The modular architecture and hemispheric asymmetry in higher-order regions is compatible with segregated processing streams and lateralization of cognitive functions.

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One of the more challenging tasks in the understanding of dynamical properties of models on top of complex networks is to capture the precise role of multiplex topologies. In a recent paper, Gómez et al. [ Phys. Rev. Lett. 110 028701 (2013)], some of the authors proposed a framework for the study of diffusion processes in such networks. Here, we extend the previous framework to deal with general configurations in several layers of networks and analyze the behavior of the spectrum of the Laplacian of the full multiplex. We derive an interesting decoupling of the problem that allow us to unravel the role played by the interconnections of the multiplex in the dynamical processes on top of them. Capitalizing on this decoupling we perform an asymptotic analysis that allow us to derive analytical expressions for the full spectrum of eigenvalues. This spectrum is used to gain insight into physical phenomena on top of multiplex, specifically, diffusion processes and synchronizability.

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Within the special geometry of the simplex, the sample space of compositional data, compositional orthonormal coordinates allow the application of any multivariate statistical approach. The search for meaningful coordinates has suggested balances (between two groups of parts)—based on a sequential binary partition of a D-part composition—and a representation in form of a CoDa-dendrogram. Projected samples are represented in a dendrogram-like graph showing: (a) the way of grouping parts; (b) the explanatory role of subcompositions generated in the partition process; (c) the decomposition of the variance; (d) the center and quantiles of each balance. The representation is useful for the interpretation of balances and to describe the sample in a single diagram independently of the number of parts. Also, samples of two or more populations, as well as several samples from the same population, can be represented in the same graph, as long as they have the same parts registered. The approach is illustrated with an example of food consumption in Europe

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Cette thèse appréhende les rapports au politique des artistes visuels yéménites dans un contexte de domination, recouvrant trois États (les deux républiques qui précédent l'unification du Yémen et la république actuelle créée en 1990, jusqu'en 2015). En étudiant la domination en acte à travers une démarche ethnographique, ce travail interroge les conditions de production et d'action des artistes en soutien ou en contestation au régime, comme au cours du moment révolutionnaire de 2011. On observe ainsi le processus de politisation des mondes de l'art au Yémen contemporain, processus compris en tant qu'acquisition d'une signification politique par la pratique artistique et par les réseaux de relations entretenus par les artistes visuels. Ces requalifications de leur travail ou de leurs actions se font dans un contexte traversé par des luttes concurrentielles pour la répartition du pouvoir, aussi bien internes et propres à leurs mondes d'activité, qu'externes et en relation à l'espace politique institutionnel. La politisation des mondes de l'art apparaît dès lors moins comme un instrument d'accès à cet espace qu'une voie pour accéder à plus de visibilité, à la reconnaissance, et à un meilleur positionnement dans les rapports agonistiques qui configurent ces mondes. -- This thesis focuses on the study of Yemeni visual artists' relation to politics in a context of domination, covering three States (the two republics that precede Yemen's unification and the current republic established in 1990, until 2015). Studying domination in action througli an ethnographic approach, this work questions artists' conditions of production and of action in support to or in contestation of the regime- as in the case of the revolutionary period of 2011. It observes the politicization of art worlds in contemporary Yemen, a process understood as the acquisition of a political significance as observed in the artistic practice and in the dynamic networks that artists maintain. The requalification and reclassification of their work and their actions that results from the politicization of art worlds, takes place in a context of competitive struggles over distribution and access to sites of power. Such conflict over power occurs within their own worlds of activity as well as outside them and in relation to the domain of institutional politics. This thesis contends that the politicization of art worlds is more of a means to access visibility and recognition than a resource to participate in the political field. Through the politicization of art, artists are able to better position themselves within the agonistic relations that exist within art worlds.

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Biomedical research is currently facing a new type of challenge: an excess of information, both in terms of raw data from experiments and in the number of scientific publications describing their results. Mirroring the focus on data mining techniques to address the issues of structured data, there has recently been great interest in the development and application of text mining techniques to make more effective use of the knowledge contained in biomedical scientific publications, accessible only in the form of natural human language. This thesis describes research done in the broader scope of projects aiming to develop methods, tools and techniques for text mining tasks in general and for the biomedical domain in particular. The work described here involves more specifically the goal of extracting information from statements concerning relations of biomedical entities, such as protein-protein interactions. The approach taken is one using full parsing—syntactic analysis of the entire structure of sentences—and machine learning, aiming to develop reliable methods that can further be generalized to apply also to other domains. The five papers at the core of this thesis describe research on a number of distinct but related topics in text mining. In the first of these studies, we assessed the applicability of two popular general English parsers to biomedical text mining and, finding their performance limited, identified several specific challenges to accurate parsing of domain text. In a follow-up study focusing on parsing issues related to specialized domain terminology, we evaluated three lexical adaptation methods. We found that the accurate resolution of unknown words can considerably improve parsing performance and introduced a domain-adapted parser that reduced the error rate of theoriginal by 10% while also roughly halving parsing time. To establish the relative merits of parsers that differ in the applied formalisms and the representation given to their syntactic analyses, we have also developed evaluation methodology, considering different approaches to establishing comparable dependency-based evaluation results. We introduced a methodology for creating highly accurate conversions between different parse representations, demonstrating the feasibility of unification of idiverse syntactic schemes under a shared, application-oriented representation. In addition to allowing formalism-neutral evaluation, we argue that such unification can also increase the value of parsers for domain text mining. As a further step in this direction, we analysed the characteristics of publicly available biomedical corpora annotated for protein-protein interactions and created tools for converting them into a shared form, thus contributing also to the unification of text mining resources. The introduced unified corpora allowed us to perform a task-oriented comparative evaluation of biomedical text mining corpora. This evaluation established clear limits on the comparability of results for text mining methods evaluated on different resources, prompting further efforts toward standardization. To support this and other research, we have also designed and annotated BioInfer, the first domain corpus of its size combining annotation of syntax and biomedical entities with a detailed annotation of their relationships. The corpus represents a major design and development effort of the research group, with manual annotation that identifies over 6000 entities, 2500 relationships and 28,000 syntactic dependencies in 1100 sentences. In addition to combining these key annotations for a single set of sentences, BioInfer was also the first domain resource to introduce a representation of entity relations that is supported by ontologies and able to capture complex, structured relationships. Part I of this thesis presents a summary of this research in the broader context of a text mining system, and Part II contains reprints of the five included publications.