Search results for "RAV"

Real Line Arrangements and Surfaces with Many Real Nodes

2008

A long standing question is if the maximum number μ(d) of nodes on a surface of degree d in P( ) can be achieved by a surface defined over the reals which has only real singularities. The currently best known asymptotic lower bound, μ(d) 5 12 d, is provided by Chmutov’s construction from 1992 which gives surfaces whose nodes have non-real coordinates. Using explicit constructions of certain real line arrangements we show that Chmutov’s construction can be adapted to give only real singularities. All currently best known constructions which exceed Chmutov’s lower bound (i.e., for d = 3, 4, . . . , 8, 10, 12) can also be realized with only real singularities. Thus, our result shows that, up t…

The Spanning Tree based Approach for Solving the Shortest Path Problem in Social Graphs

2016

Nowadays there are many social media sites with a very large number of users. Users of social media sites and relationships between them can be modelled as a graph. Such graphs can be analysed using methods from social network analysis (SNA). Many measures used in SNA rely on computation of shortest paths between nodes of a graph. There are many shortest path algorithms, but the majority of them suits only for small graphs, or work only with road network graphs that are fundamentally different from social graphs. This paper describes an efficient shortest path searching algorithm suitable for large social graphs. The described algorithm extends the Atlas algorithm. The proposed algorithm so…

Developing and Integrating Advanced Movement Features Improves Automated Classification of Ciliate Species

2015

Recent advances in tracking technologies such as GPS or video tracking systems describe the movement paths of individuals in unprecedented details and are increasingly used in different fields, including ecology. However, extracting information from raw movement data requires advanced analysis techniques, for instance to infer behaviors expressed during a certain period of the recorded trajectory, or gender or species identity in case data is obtained from remote tracking. In this paper, we address how different movement features affect the ability to automatically classify the species identity, using a dataset of unicellular microbes (i.e., ciliates). Previously, morphological attributes a…

The indirect force method

1990

Abstract It is known that the matrix force method shows some advantages over the displacement method for certain classes of problems, particularly in optimization and in the stress concentration analysis. Notwithstanding this, few efforts have been made to employ this method in engineering problems. In this paper, within the elastic analysis of frames and trusses, the indirect force method, utilizing beam-node type finite elements, is proposed. This method is based on the kinematical and mechanical study of nodes and of beams, the latter connected with the nodes by their first extremes according to a preliminary arrangement. In this formulation kinematical singularities are included, in the…

Synthesis and Spectroscopic Properties of Silica−Dye−Semiconductor Nanocrystal Hybrid Particles

2010

We prepared silica-dye-nanocrystal hybrid particles and studied the energy transfer from semiconductor nanocrystals (= donor) to organic dye molecules (= acceptor). Multishell CdSe/CdS/ZnS semiconductor nanocrystals were adsorbed onto monodisperse Stöber silica particles with an outer silica shell of thickness 2-23 nm containing organic dye molecules (Texas Red). The thickness of this dye layer has a strong effect on the energy transfer efficiency, which is explained by the increase in the number of dye molecules homogeneously distributed within the silica shell, in combination with an enhanced surface adsorption of nanocrystals with increasing dye amount. Our conclusions were underlined by…

Regards croisés sur les conditions de réussite dans l'enseignement supérieur français : rapport pour le CNESCO

2018

Regards croisés sur les conditions de réussite dans l'enseignement supérieur français

2019

Référence interne : 19046http://www.cnesco.fr/wp-content/uploads/2019/08/190801_Cnesco_Post-baccalaureat_Giret_Morlaix-_dir.pdf

Stratégies et trajectoires des jeunes sans diplôme: Éléments d'évaluation du dispositif de formation et d'insertion des jeunes de 16 à 18 ans en Bour…

1985

International audience; Étude des stratégies et des trajectoires des jeunes sortis sans diplôme du système scolaire et évaluation de l'impact du passage par le "dispositif 16-18" sur ces trajectoires. Enquêtes par interviews auprès de jeunes urbains et ruraux, un sous-groupe de jeunes étant passé par le dispositif, l'autre n'y étant pas passé, de façon à pouvoir comparer les trajectoires.

Disseminated Intravascular Coagulation

1985

During the past decade, diffuse intravascular coagulation (DIC) has been one of the most intensively studied subjects in hematology. DIC is a dynamic pathologic process caused by the entrance of foreign material into the circulation, or by exposure to abnormal surfaces. The intravascular coagulation is triggered by activation of the clotting cascade with resultant generation of excess thrombin within the vascular system that leads to further activation of the coagulation system, shortened survival of certain hemostatic elements, deposition of fibrin in the microcirculation, and activation of the fibrinolytic system. Decreased levels of hemostatic factors, secondary fibrinolysis, and exhaust…

Successful management of heparin-induced thrombocytopenia using argatroban in a very old woman: a case report.

2012

Thrombosis due to heparin-induced thrombocytopenia (HIT) is rare but has a severe prognosis. Its management is not always easy, particularly in old patients with renal insufficiency. A 95-year-old woman was hospitalized for dyspnea. Curative treatment with unfractionated heparin was started because pulmonary embolism was suspected. Disseminated intravascular coagulation was then suspected because of thrombocytopenia, hypoprothrombinemia, hypofibrinogenemia, and a positive ethanol gelation test. The first immunoassay for HIT was negative. On the 12th day of hospitalization, bilateral cyanosis of the toes occurred associated with recent deep bilateral venous and arterial thrombosis at duplex …