Playing with population protocols

Abstract. Population protocols have been introduced as a model of sensor networks consisting of very limited mobile agents with no control over their own movement: A collection of anonymous agents, modeled by finite automata, interact in pairs according to some rules. Predicates on the initial configurations that can be computed by such protocols have been characterized under several hypotheses. We discuss here whether and when the rules of interactions between agents can be seen as a game from game theory. We do so by discussing several basic protocols.

Outil de prise de décision pour différentes options technologiques émergentes en bioraffinage forestier liées à la production de bioéthanol

RÉSUMÉ L’accès à de nouvelles sources d’énergie renouvelable est un élément clé en ce début de XXIème siècle. L’indépendance vis-à-vis des combustibles fossiles semble difficile à court terme mais de nombreux autres secteurs tels que les énergies solaires, éoliennes ou encore l’apparition de nouveaux biocarburants verts tendent à augmenter la part des énergies renouvelables sur le marché de l’énergie. Dans cette optique le développement du bioraffinage forestier (BRF) - dont l’objectif est de maximiser l’utilisation de la biomasse et de la valoriser via le développement de nouveaux bioproduits - s’est considérablement accru au cours des quinze dernières années et plus particulièrement en Amérique du Nord et en Europe par l’intermédiaire de nombreux investissements publics et privés. Au Canada, le BRF trouve une opportunité particulièrement intéressante dans le secteur des pâtes et papiers (P&P), en grande difficulté financière depuis le début des années 1990. En effet, le BRF offre une opportunité considérable pour cette industrie d’améliorer voire de transformer ses plans d’affaires en ajoutant de nouveaux produits à leurs familles traditionnelles pour ainsi diversifier leurs revenus et améliorer leur compétitivité sur le marché. La palette de bioproduits accessibles est considérable: des produits chimiques de commodité (acides, alcool, etc.), divers biocarburants jusqu’à des produits de haute valeur ajoutée (nutraceutiques et pharmaceutiques). En Amérique du Nord, les biocarburants jouissent d’une demande sur le marché en constante augmentation en particulier le bioéthanol de deuxième génération cible de nombreux développeurs de technologies qui veulent assurer sa production à grande échelle dans les années à venir (e.g. premières échelles de production de 40 à 60 Millions de gallons) en bénéficiant de nombreuses aides d’organismes gouvernementaux sous diverses formes (subventions, prêts, possibilités de bénéficier des crédits carbone). Ainsi le bioéthanol représente une cible d’intérêt à court terme pour les sociétés du secteur des P&P pour leur permettre de considérer l’implantation et la possible intégration de diverses technologies émergentes dans leur contexte d’usines par l’intermédiaire de projets de conception et d’ingénierie usuels. Néanmoins, la grande variabilité dans les échelles de développement de ces technologies, le manque d’informations et l’incertitude liée à leur utilisation rend l’évaluation et la comparaison de ces technologies difficiles. Ainsi, le risque que prend une société papetière à considérer l’intégration de technologies BRF est important. En effet, du fait de l’investissement majeur demandé pour leur implantation, ces compagnies ne peuvent se permettre des choix stratégiques non calculés. Afin de soutenir une stratégie de diversification des revenus, les procédés sélectionnés doivent donc assurer un bon Retour sur Investissement (ROI) et un certain niveau de maturité technologiques. Pour permettre à ces sociétés de minimiser les risques lors de leur prise de décision, il est donc nécessaire de pouvoir trier ces technologies émergentes très tôt afin d’identifier les plus prometteuses avant d’entreprendre toute étude de conception et d’ingénierie détaillée reliée à leur intégration aux usines considérées.----------ABSTRACT Having access to new renewable sources of energy is a key issue today in the beginning of the XXIst century. Being independent from fossil energy sources seems impossible in the short term but new sources of renewable energy are being developed in the market as solar and wind energy systems. As an example, the development of the forest biorefinery (FBR) to maximize the use of lignocellulosic feedstocks to produce new bioproducts dramatically evolved over the last fifteen years, especially in North America and Europe. In Canada, the biorefinery has an interesting application in the forest sector and especially in pulp & paper companies facing a difficult financial situation since the beginning of 1990. Indeed, the FBR offers a unique opportunity for this industry sector to improve and transform their way of doing business and add new products to their existing P&P portfolio in order to increase their revenue and gain competitiveness. A huge diversity of products could be reached thanks to biorefinery technologies: from commodity chemicals (acids, alcohols, etc.) to biofuels or even added-value chemicals (nutraceuticals and pharmaceuticals). Biofuels currently have a huge demand on the North American market and especially second-generation ethanol. Numerous technology providers are willing to develop its production in the upcoming years (e.g. development scales between 40 and 60 Million gallons.) thanks to potential federal support (grants, loans, carbon credits). Ethanol would then represent a good opportunity in the short term for these P&P companies to consider the integration of various FBR technologies in their mills. Nevertheless, the discrepancy among scales of development between all these technologies and the scarcity and uncertainty of information needed to evaluate them make technology assessments even more difficult. Thus, investing in the FBR sector for integrating new technologies implies risk taking from P&P companies: not choosing a mature technology with economic and technological guarantees could potentially deteriorate the already dramatic economic situation. To minimize risk taking and allow efficient decision, previous to any early stage design study, it is important to be able to critically evaluate the future potential of proven as well as emerging FBR technologies and triage them before any more detailed design study is done regarding their integration in mill contexts

Playing With Population Protocols

Population protocols have been introduced as a model of sensor networks consisting of very limited mobile agents with no control over their own movement: A collection of anonymous agents, modeled by finite automata, interact in pairs according to some rules. Predicates on the initial configurations that can be computed by such protocols have been characterized under several hypotheses. We discuss here whether and when the rules of interactions between agents can be seen as a game from game theory. We do so by discussing several basic protocols

The proposed reform of the European Stability Mechanism must be postponed

Eurozone finance ministers reached a preliminary agreement on a reform of the European Stability Mechanism in June, but failed to conclude it last week. The reform is now set to be discussed during the European Council meeting on 12-13 December. Shahin Vallée, Jérémie Cohen-Setton, Paul De Grauwe and Sebastian Dullien write that the proposal should not be endorsed in its current form. They argue it would represent a missed opportunity to secure a broader and more ambitious reform package

Asia-Europe: The Third Link

Trade integration within Europe is significantly closer than within the other two regions; however trade integration within East Asia is growing very rapidly while it has stalled within the North American region. Vis-à-vis the rest of the world, East Asia's trade openness (not counting trade within the region) is twice higher than North America's. Europe's openness lies in between. Financial integration within Europe has increased dramatically in the last decade, with a near-tripling of the cross-border asset holdings-to-GD

Die Schuldenbremse und der europäische Fiskalkurs nach Covid-19

Eine übereilte Rückkehr zu den europäischen und deutschen Fiskalregeln wird den Aufschwung abwürgen und die Bemühungen um eine Erneuerung der transatlantischen Beziehungen in den Bereichen Handel und makroökonomische Zusammenarbeit untergraben. Dieser Policy Brief präsentiert Optionen, die mit einer Rückkehr zur Schuldenbremse verbundene fiskalische Belastung zu mindern

Separation Practices in Children and Adolescents Admitted for Suicidal Behavior: A National Survey of French Psychiatrists

ObjectivesTo assess practices of French psychiatrists regarding their management of children and adolescents with suicidal behaviors, focusing on the use of a separation protocol in which the youths are separated from their relatives.MethodsIn 2017, we conducted an online cross-sectional survey of French psychiatrists caring for children and adolescents. Participants were asked to describe their practice of a separation protocol in children and adolescents admitted for suicidal behavior. Our main analysis followed a descriptive approach. We also explored whether participant characteristics were associated with the use of a separation protocol.ResultsThe response rate was 218/2403 (9,1%); 57.9 % of respondents worked in a University hospital, and 60% of respondents reported routinely hospitalizing children. A separation protocol was set up by 91.1% of survey participants (systematically 39.6%, on a case-by-case basis 51.5%). The mean age from which a separation protocol was indicated was above 11 years; 64% of participants reported a separation period of ≤ 48 h. The most common (87%) criterion cited for establishing a separation period was family relationship difficulties. The most common (80.9%) reason to justify the use of a separation protocol was to allow a better clinical assessment. Exploratory analyses did not identify any participant characteristics associated with the use of a separation protocol (p > 0.2 for all).ConclusionThe use of a separation protocol in children and adolescents admitted for suicidal behavior is a widespread practice in France, despite the deprivation of liberty it implies. This raises the question of the relevance and usefulness of such a practice