485 research outputs found
Géopolitique de la Turquie à partir du Grand échiquier de Zbignew Brzezinski
Cet essai prend comme point de départ l'ouvrage de Zbignew Brzezinski, LeGrand échiquier, L'Amérique et le reste du monde, pour faire une analyse géopolitique de la Turquie. Dans son livre, Zbignew Brzezinski qualifie successivement la Turquie de « pivot géopolitique de premier ordre » et « d'important acteur géostratégique dans la région des Balkans eurasiens ». Il s'agit d'illustrer ces deux caractéristiques et de les passer au crible de la réalité. Malgré la disparition de I'URSS, la Turquie demeure un important pivot géopolitique. Si son rôle de sentinelle du monde occidental face à la grande puissance septentrionale a quelque peu évolué, le redéploiement effectué vers le Moyen-Orient confère toujours à la Turquie une position-clé dans la région. Le qualificatif d'acteur géostratégique régional pose davantage problème. Certes, des Balkans à Chypre en passant par l'Asie centrale, la Turquie est en mesure de prouver ses capacités d'influence. Mais ne s'agit-il pas avant tout d'une influence ponctuelle, sur des espaces bien délimités, voire potentielle ? L'exemple de l'Asie centrale est ici révélateur, Ankara ayant bien été obligée de passer vis-à -vis du « monde turc », au début des années 1990, des illusions au réalisme. Par ailleurs, l'accumulation de difficultésinternes concernant notamment le problème kurde, la place de la mouvance islamique dans le système politique, le développement de la mafia, les disparités économiques et sociales, risque d'hypothéquer les capacités d'influence externe de la TurquieThis article is a geopolitical analysis ofTurkey taking Zbignew Brzezinski'sbook The Grand Chessboard : American Primacy and its Geostrategic Imperativesas a starting point. In his book, Zbignew Brzezinski successively characterizes Turkey as a «first-class geopolitical pivot » and an « important geostrategic actor in the Eurasian Balkans region ». Those two characterizations are illustrated and thoroughly analysed here. Despite the disappearance of the URSS, Turkey is still an important geopolitical pivot. If its role as a guard of the Western worldfacing the big Northern power has evolved quite a bit, the redeployment towards the Middle East still grants Turkey a key position in the region. The term regional geostrategic actor is more controversial. Indeed, from the Balkans to Cyprus to Central Asia, Turkey is able to demonstrate its influence. But is it only a sporadic influence, exerted over well-defined spaces, or even a potential influence ? The case of Central Asia is a telling one here; in the early 1990's, Ankara had to switch from illusions to realism vis-à -vis the « Turkish world ». In addition, growing domestic issues such as the Kurdish problem, the sphere of influence of Islam in thepolitical System, the development ofa mafia, and the social and economic disparities, may undermine Turkey's external influence
Numerical methods for meteorology and climatology
Efficient numerical methods for long term weather forecasting are developed. One implicit and one explicit scheme are compared as to accuracy
A Relation Extraction Approach for Clinical Decision Support
In this paper, we investigate how semantic relations between concepts
extracted from medical documents can be employed to improve the retrieval of
medical literature. Semantic relations explicitly represent relatedness between
concepts and carry high informative power that can be leveraged to improve the
effectiveness of retrieval functionalities of clinical decision support
systems. We present preliminary results and show how relations are able to
provide a sizable increase of the precision for several topics, albeit having
no impact on others. We then discuss some future directions to minimize the
impact of negative results while maximizing the impact of good results.Comment: 4 pages, 1 figure, DTMBio-KMH 2018, in conjunction with ACM 27th
Conference on Information and Knowledge Management (CIKM), October 22-26
2018, Lingotto, Turin, Ital
Eficiência de diferentes estratégias de controle para a pandemia da Covid-19 para a mesorregião do sul/sudoeste mineiro
Neste artigo buscamos analisar os efeitos das polÃticas de controle para a pandemia na mesorregião do sul/sudoeste de Minas Gerais. Usamos um modelo SEIR estruturado por idade com uma classe de quarentena e dois tipos de controle. O primeiro estuda a sensibilidade do número básico de reprodução, , em relação aos parâmetros e é calculado fazendo-se uso do método da nova geração. O segundo avalia diferentes estratégias de quarentena comparando o número total de mortos em cada caso. Analisaram-se diferentes estratégias de quarentena através dos dados coletados do recorte espacial estudade, assim foi possÃvel compreender as estratégias possÃveis de quarentena para a região popularmente chamada de Sul de Minas. Como resultado, dentre todas as observações indicadas, temos que o fator tempo é determinante na efetividade da estratégia de quarentena escolhida
DeFi composability as MEV non-interference
Complex DeFi services are usually constructed by composing a variety of
simpler smart contracts. The permissionless nature of the blockchains where
these smart contracts are executed makes DeFi services exposed to security
risks, since adversaries can target any of the underlying contracts to
economically damage the compound service. We introduce a new notion of secure
composability of smart contracts, which ensures that adversaries cannot
economically harm the compound contract by interfering with its dependencies
Steam injection into water-saturated porous rock
We formulate conservation laws governing steam injection in a linear porous medium containing water. Heat losses to the outside are neglected. We find a complete and systematic description of all solutions of the Riemann problem for the injection of a mixture of steam and water into a water-saturated porous medium. For ambient pressure, there are three kinds of solutions, depending on injection and reservoir conditions. We show that the solution is unique for each initial data
Nonlinear wave interactions in geochemical modeling
This paper is concerned with the study of the main wave interactions in a
system of conservation laws in geochemical modeling. We study the modeling of
the chemical complexes on the rock surface. The presence of stable surface
complexes affects the relative permeability. We add terms representing surface
complexes to the accumulation function in the model presented in
\cite{lambert2019nonlinear1}. This addition allows to take into account the
interaction of ions with the rock surface in the modeling of the oil recovery
by the injection of carbonated water. Compatibility hypotheses with the
modeling are made on the coefficients of the system to obtain meaningful
solutions. We developed a Riemann solver taking into account the complexity of
the interactions and bifurcations of nonlinear waves. Such bifurcations occur
at the inflection and resonance surfaces. We present the solution of a
generalized eigenvalue problem in a (n+1)-dimensional case, which allows the
construction of rarefaction curves. A method to find the discontinuous
solutions is also presented. We find the solution path for some examples
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