Search results for "Paris"

Performance Comparison of SSMF and UltraWave Fibers for Ultra-Long-Haul 40-Gb/s WDM Transmission

2007

International audience; We experimentally compare the performance of standard single-mode fiber (SSMF) and UltraWave fiber (UWF) for ultra-long-haul (ULH) 40-Gb/s wavelength-division-multiplexing transmissions. We used the carrier-suppressed return-to-zero amplitude-shift-keying (CSRZ-ASK) and the carrier-suppressed return-to-zero differential-phase-shift-keying (CSRZ-DPSK) formats, which are particularly well-adapted to 40-Gb/s pulse-overlapped propagation. We demonstrate that transmission distance well beyond 2000 km can be reached on UWF with both the CSRZ-ASK and CSRZ-DPSK formats, or on SSMF with the CSRZ-DPSK format only, thus indicating that SSMF-based infrastructure of incumbent car…

About the link between the detailed description of transitions in an ion and the average-ion models

2009

We study the link which exists between microscopic (detailed) models for the evolution of the electronic configurations in a population of ions and the macroscopic (average ion) models. Rigorous asymptotics are presented in situations where they exist (large temperature; almost empty or almost full shells), and numerical simulations are presented.

Models and solution methods for the uncapacitatedr-allocationp-hub equitable center problem

2017

Hub networks are commonly used in telecommunications and logistics to connect origins to destinations in situations where a direct connection between each origin–destination (o-d) pair is impractical or too costly. Hubs serve as switching points to consolidate and route traffic in order to realize economies of scale. The main decisions associated with hub-network problems include (1) determining the number of hubs (p), (2) selecting the p-nodes in the network that will serve as hubs, (3) allocating non-hub nodes (terminals) to up to r-hubs, and (4) routing the pairwise o-d traffic. Typically, hub location problems include all four decisions while hub allocation problems assume that the valu…

Memorandum on Latvia: addressed to the Peace Conference

1919

Capparis kebarensis, a new species of Capparaceae from Papua Barat, Indonesia

2012

The new species Capparis kebarensis Fici (Capparaceae) is here described and illustrated. Its affinities are discussed.

Establishing the relative importance of sympatric definitive hosts in the transmission of the sealworm, Pseudoterranova decipiens: a host-community a…

2001

The importance of a given host to a particular parasite can be determined according to three different criteria: host preference, host physiological suitability and host contribution to transmission. Most studies on the sealworm Pseudoterranova decipiens have focussed on the latter factor, but few attempts have been made to develop a quantitative transmission model evaluating the relative importance of each host. The purpose of this study was to propose a flow-chart model to study sealworm transmission within a seal community. The model was applied to hypothetical data of four seal species acting as definitive hosts of P. decipiens sensu stricto in eastern Canada: harp seal Phoca groenlandi…

Empirical and theoretical study of atelostomate (Echinoidea, Echinodermata) plate architecture: using graph analysis to reveal structural constraints.

2015

AbstractDescribing patterns of connectivity among organs is essential for identifying anatomical homologies among taxa. It is also critical for revealing morphogenetic processes and the associated constraints that control the morphological diversification of clades. This is particularly relevant for studies of organisms with skeletons made of discrete elements such as arthropods, vertebrates, and echinoderms. Nonetheless, relatively few studies devoted to morphological disparity have considered connectivity patterns as a level of morphological organization or developed comparative frameworks with proper tools. Here, we analyze connectivity patterns among apical plates in Atelostomata, the m…

Absorption of Structural Funds – International Comparisons and Correlations

2013

Abstract Structural Funds represent one of the main instruments which The European Union uses to sustain regional development and to eliminate disparities between members. Specialized literature is relatively poor when it comes to approaching this subject. In the period 2002-2006, several papers were written, which identified the absorption process's influence factors, but all these materials represented ex-ante analysis, the empirical testing of theories being virtually impossible. The present paper, based on available statistical data related to the absorption process, aims at testing these factors, trying to elucidate the great differences obtained by the EU members within Central and Ea…

Eco‐tourism Certification – Does it Make a Difference? A Comparison of Systems from Australia, Costa Rica and Sweden

2010

Abstract In the current context of climate change, discussions about tourism sustainability are gaining increased momentum. Over the past decade, some operators worldwide have started to certify their products and services as ecotourism or sustainable tourism. A certification or approval is considered to be a sign of general high product quality as well as an indication of environmentally and socially sound products. In this research note, we examine three different ecotourism certification and approval systems – from Sweden, Costa Rica and Australia. The note is based on a literature review of three different approval systems, conducted parallel to the planning of the Norwegian approval sy…

L'éducation en Afrique sub-saharienne. Les indicateurs d'efficience et leur utilisation politique

2005

05047; National audience; Cet article examine l'idée selon laquelle les systèmes éducatifs africains ne souffriraient pas tant d'un manque de ressources que d'une mauvaise utilisation de celles-ci. Deux arguments soutiennent cette idée. Le premier relève d'une comparaison internationale de l'efficience fondée sur un indicateur -part des dépenses d'éducation dans le PIB / durée moyenne de scolarisation- défectueux. Le second rrelève de l'estimation des fonctions de production scolaire dont l'interprétation commune des résultats est incorrrecte. Cette double argumentation, discutable, dissuade une forte augmentation de l'aide et encourage l'expansion de systèmes dont la médiocrité, conforme à…