UCLP in flow state router platforms

Actualment, els serveis òptics són essencialment estàtics, en els que els usuaris sol•liciten als proveïdors o ISPs l’ample de banda que necessiten durant un cert període de temps. Aquest serveis s’aprovisionen de forma manual, la qual cosa pot suposar un treball llarg i costós. Els usuaris o les mateixes aplicacions necessiten flexibilitat per controlar els seus serveis al llarg de diferents dominis independents, ja que estan en millor posició que els proveïdors per escollir i gestionar camins òptics adaptats a les seves necessitats. Aquesta idea ha donat lloc a un nou paradigma en el mon de les xarxes anomenat “xarxes controlades per usuaris”. Amb el patrocini de Canarie, s’està duent a terme una investigació per tal d’aconseguir les xarxes controlades pels usuaris. D’aquesta investigació ha sorgit un sistema anomenat "User-Controlled Lightpath Provisioning" (UCLP) (Provisió de camins òptics controlats per usuaris) que permet als usuaris establir canals òptics d’extrem a extrem a través de diferents Sistemes Autònoms. Aquest software s’està desenvolupant al CRC (Communications Research Centre, Canada) amb la col•laboració de la Fundació i2Cat. UCLP es un sistema de gestió distribuït que utilitza la idea de OON (Objecte Orientat a Xarxa) i que es pot explicar com una eina de partició i configuració que representa cada recurs d’una xarxa física (fibres, targetes) com un servei o objecte. Aquest servei/objecte es pot posar sota el control de diversos usuaris de la xarxa per tal que puguin crear les seves pròpies topologies de xarxa IP. Fins ara, UCLP treballava amb equips de capa 1 i 2. El principal objectiu d’aquest projecte és trobar una solució per integrar equips de capa 3 al sistema. Concretament, es vol introduir un router basat en una nova tecnologia anomenada “estat de flux” (flow-state). Aquesta tecnologia, que permet reconèixer fluxos basats en determinades funcions de hash, realitza un extens procés al primer paquet d’un flux, associa aquest flux amb un estat i aplica el resultat d’aquest procés als següents paquets del flux, amb els quals, enlloc de realitzar enrutament, simplement els reenviarà sense mirar les taules d’enrutament

Comparison between two estimation methods of the complex gain of an optimal Wiener filter

This paper deals with the adoptive estimation of a linear and stationary filter in noise cancelling . The optimal Wiener filter is solution of the minimization of a quadratic criterion . It needs.the estimation of the power spectra af the observed signais. Filtering operation in the frequency-domain may produce estimation 'errors if we take no precaution . We compare in this paper two methods called « Overlap-add-method » and « Overlap-save-method » which aim is to reduce these errors .Cet article traite de l'estimation adaptative du gain complexe d'un filtre linéaire et stationnaire appliqué à la soustraction de bruit . Le filtre optimal est déterminé au sens de la minimisation d'un critère quadratique statistique : son gain complexe est solution de l'équation de Wiener-Hopf . En pratique, il est nécessaire d'estimer les densités spectrales des signaux observés à l'aide, par exemple, de périodogrammes moyennés . La mise en ouvre du soustracteur de bruit, réalisée sans précaution, peut entraîner des erreurs d'estimations importantes liées à l'opération de filtrage linéaire dans le domaine fréquentiel . Deux techniques, connues sous les noms d'« Overlap-addmethod » et « Overlap-save-method », ont pour but de diminuer ces erreurs . Celles-ci conduisent à deux estimateurs différents du gain complexe du filtre . Nous les comparons en étudiant les propriétés statistiques au second ordre des estimateurs . Les résultats obtenus sont validés par des simulations

Confocal Raman-in-SEM Imaging: a New Method for 3D Morphology of Asbestos- like Fibers in a Mineral Matrix -Complementarity with SEM-FIB

International audienceAsbestos consists of natural mineral fibers crystallized in a specific way with specific properties including flexibility, high tensile strength, resistance to heat and chemical degradation. The term asbestos refers to one fibrous serpentine, and five asbestiform varieties of amphiboles [1][2]. Asbestos is considered a Category 1 human carcinogen (e.g. [1][3][4][5][6]), as inhalation of asbestos fibers causes respiratory diseases, in particular asbestosis, lung cancers and malignant mesothelioma. Due to the pathogenicity of asbestos fibers, their use has been banned in most countries around the world. The classification as "asbestos" comprises three main characteristics: sub-micrometric fibrous morphology (so-called asbestiform), chemistry and crystallography (i.e. mineralogy). The ban applies to natural materials, which are quarried and used for public works projects. Compliance with existing rules requires accurate diagnosis of the asbestos or non-asbestos nature of the materials likely to be exploited in a quarry or involved in the opening of a construction site. Conventional methods for asbestos diagnosis, mainly based on the use of TEM, are hard to apply to massive materials as the sample preparation protocol is complex, it is likely to release artifacts like cleavage fragments, or sample-piece thinning is costly and hard to achieve and thus not applicable in routine analysis. The use of a LV-FE-SEM-EDS (Low vacuum field emission gun scannning electron microscope equiped with energy dispersive spectroscopy) coupled to confocal Raman-in-SEM imaging (RISE) is a new and efficient method for identifying the mineral nature of sub-micrometer fibers or fibrous bundles. SEM coupled to EDS provides a qualitative or semi-quantitative composition of the fiber. The crystal structure is determined by confocal Raman spectroscopy (with lateral resolution down to 360 nm [7]). Thus the combination of these two kinds of information allows for accurate identification of both the nature and the morphology of the mineral. The combination of SEM, EDS and confocal Raman imaging in a unique analytical system (RISE) allows precise location of the same area / fiber and identification of its mineral nature. In addition, RISE allows the acquisition of 3D data, which is able to provide morphological information of the mineral distribution in the sample volume and leading to the determination of the aspect ratio, a critical parameter for asbestos (i.e. asbestiform or non-asbestiform). Moreover, this combination of techniques is not destructive. The coupling of SEM-EDS with RISE is a powerful analytical system that simplifies and reinforces existing analytical procedures. For highest resolution studies of fibers in the sample volume (3 D imaging), the RISE can be connected to a FIB-SEM [7]. Although FIB volume reconstruction is a destructive method, the resolution of the voxel can be extended to below 100 nm [8] – a resolution sufficient for visualizing even the thinnest fibers. Furthermore, Raman 3D view is an efficient tool for sampling TEM slices using the FIB

“Angular resolution expected from iCHORD orientation maps through a revisited ion channeling model”

International audienceCrystalline orientation maps are obtained in a Focused Ion Beam (FIB) microscope using the ion CHanneling ORientation Determination (iCHORD) method, which relies on the channeling phenomenon observed in ion-induced secondary electron images. The current paper focuses on the angular resolution that can be expected from such orientation maps, obtained using a revisited ion channeling model. A specific procedure was developed to evaluate the angular resolution, based on the distribution of orientation errors when evaluating controlled sample disorientation. The main advantage is that no external reference is required. An angular resolution of 1° is obtained on a nickel based sample using standard acquisition conditions. This value fulfills most of the needs in terms of microstructural characterization usually carried out by Electron Back Scattered Diffraction

Influence of step structure on preferred orientation relationships of Ag deposited on Ni(111)

Previous studies have shown that the orientation relationships which develop in hetero-epitaxy are strongly influenced by the alignment of steps in the deposit with the pre-existing steps of the substrate. In this paper we use a combination of experiments with computer simulations to identify the important influence of substrate step structure on the eventual orientation relationships that develop in the deposit. We have made use of Ag deposited on Ni as it has been used extensively as a model system for the study of hetero-epitaxy. This system displays a large lattice mismatch of 16%. It is shown that on any surface vicinal to Ni(111), which has two possible kinds of steps (A-steps with {100} ledges and B-steps with {111} ledges), a Ag deposit adopts a single orientation relationship because only A-steps remain stable in the presence of Ag.Comment: Acta Materialia, Elsevier, In pres

Insomnia among patients with advanced disease during admission in a Palliative Care Unit : a prospective observational study on its frequency and association with psychological, physical and environmental factors

The aims of this study were: 1) to assess the frequency of insomnia among patients during admission in a Palliative Care Unit (PCU); 2) to study the association between emotional distress and insomnia, taking physical, environmental and other psychological factors into account. Prospective observational study including patients consecutively admitted to a PCU during eight months, excluding those with severe cognitive problems or too low performance status. Insomnia was assessed by asking a single question and by using the Sleep Disturbance Scale (SDS), and emotional distress using the Hospital Anxiety and Depression Scale (HADS). Physical, environmental and other psychological factors potentially interfering with sleep quality were evaluated. Association between insomnia and the factors evaluated was studied using univariate and multivariate regression analyses. 61 patients were included (mean age 71.5 years; 95% with oncological disease); 38 (62%) answered "yes" to the insomnia single question and 29 (47%) showed moderate to severe insomnia according to the SDS. 65% showed clinically significant emotional distress and 79% had nocturnal rumination. The physical symptoms most often mentioned as interfering with sleep quality were pain (69%) and dyspnoea (36%). 77% reported at least one environmental disturbance. In the univariate analysis, answering "yes" to the insomnia single question was significantly associated with higher HADS score, anxiety, nocturnal rumination, clear knowledge of the diagnosis, higher performance status and dyspnoea; moderate to severe insomnia was significantly associated with nocturnal rumination, higher performance status, environmental disturbances and daytime sleepiness. In the multivariate regression analysis, answering "yes" to the single question was associated with dyspnoea (OR 7.2 [1.65-31.27]; p = 0.009), nocturnal rumination (OR 5.5 [1.05-28.49]; p = 0.04) and higher performance status (OR 14.3 [1.62-125.43]; p = 0.017), and moderate to severe insomnia with nocturnal rumination (OR 5.6 [1.1-29.1]; p = 0.041), and inversely associated with daytime sleepiness (OR 0.25 [0.07-0.9]; p = 0.043). Insomnia was highly frequent. Several physical, psychological and environmental factors seemed to influence insomnia. Within the multimodal management of insomnia, the assessment of nocturnal rumination may be of particular interest, irrespective of emotional distress. Further studies with larger sample sizes could confirm this result

Démarche d'analyse spectrale en vue d'une interprétation automatique, application à un signal d'engrenages

Cet article décrit une démarche complète d'analyse spectrale commune à des experts du signal et du domaine concerné (acoustique, mécanique vibratoire) dans le but d'estimer un contenu spectral. L'originalité réside dans le processus de décision qui est fondé sur une confrontation de méthodes (Fourier, Maximum de Vraisemblance, paramétriques, déflation) couplée à une interprétation spectrale. Une pré-analyse consiste à évaluer certaines propriétés du signal (stationnarité, hypothèse gaussienne) et à étudier son autocorrélation. Ensuite, une démarche est construite à partir d'une succession d'analyses spectrales, aboutissant à la détection et à l'identification des différents motifs spectraux. L'interprétation de chaque étape est facilitée par la mise en place de critères objectifs. Enfin des analyses complémentaires sont envisagées (cyclostationnarité, recherche d'harmoniques)

Cyclostationnarités d'ordre 1 et 2 : application à des signaux vibratoires d'engrenages

Le diagnostic précoce des pannes des engrenages fait, en particulier, appel aux caractéristiques cyclostationnaires du signal vibratoire. La cyclostationarité d'un signal se manifeste sur les propriétés moyennes (ordre 1) et sur les propriétés énergétiques (ordre 2) du signal. Nous montrons l'importance de la prise en compte de ces 2 ordres de cyclostationarité pour l'analyse du signal et pour l'estimation de la corrélation spectrale. Nous appliquons cette nouvelle méthode de caractérisation à un signal vibratoire d'engrenage. L'exploitation complète des propriétés cyclostationnaires d'ordre 1 et 2 apporte de nouveaux moyens de diagnostic

Clinical, biochemical and genetic spectrum of low alkaline phosphatase levels in adults

Background: Low serum levels of alkaline phosphatase (ALP) are a hallmark of hypophosphatasia. However, the clinical significance and the underlying genetics of low ALP in unselected populations are unclear. Methods: In order to clarify this issue, we performed a clinical, biochemical and genetic study of 42 individuals (age range 20–77 yr) with unexplained low ALP levels. Results: Nine hadmild hyperphosphatemia and three hadmild hypercalcemia. ALP levelswere inversely correlated with serum calcium (r = -0.38, p = 0.012), pyridoxal phosphate (PLP; r = -0.51, p = 0.001) and urine phosphoethanolamine (PEA; r = -0.49, p = 0.001). Although many subjects experienced minor complaints, such as mild musculoskeletal pain, none hadmajor health problems.Mutations in ALPL were found in 21 subjects (50%), including six novelmutations. All but one,were heterozygousmutations.Missensemutations were themost common (present in 18 subjects; 86%) and themajority were predicted to have a damaging effect on protein activity. The presence of amutated allelewas associated with tooth loss (48% versus 12%; p=0.04), slightly lower levels of serumALP (p=0.002), higher levels of PLP (p b 0.0001) and PEA (p b 0.0001), aswell asmildly increased serum phosphate (p=0.03). Ten individuals (24%) had PLP levels above the reference range; all carried a mutated allele. Conclusion: One-half of adult individuals with unexplained low serum ALP carried an ALPL mutation. Although the associated clinicalmanifestations are usuallymild, in approximately 50% of the cases, enzyme activity is lowenough to cause substrate accumulation and may predispose to defects in calcified tissues

SNP genotyping in melons: genetic variation, population structure, and linkage disequilibrium

Novel sequencing technologies were recently used to generate sequences from multiple melon (Cucumis melo L.) genotypes, enabling the in silico identification of large single nucleotide polymorphism (SNP) collections. In order to optimize the use of these markers, SNP validation and large-scale genotyping are necessary. In this paper, we present the first validated design for a genotyping array with 768 SNPs that are evenly distributed throughout the melon genome. This customized Illumina GoldenGate assay was used to genotype a collection of 74 accessions, representing most of the botanical groups of the species. Of the assayed loci, 91 % were successfully genotyped. The array provided a large number of polymorphic SNPs within and across accessions. This set of SNPs detected high levels of variation in accessions from this crop’s center of origin as well as from several other areas of melon diversification. Allele distribution throughout the genome revealed regions that distinguished between the two main groups of cultivated accessions (inodorus and cantalupensis). Population structure analysis showed a subdivision into five subpopulations, reflecting the history of the crop. A considerably low level of LD was detected, which decayed rapidly within a few kilobases. Our results show that the GoldenGate assay can be used successfully for high-throughput SNP genotyping in melon. Since many of the genotyped accessions are currently being used as the parents of breeding populations in various programs, this set of mapped markers could be used for future mapping and breeding efforts.This project was carried out in the frame of the MELONOMICS project (2009–2012) of the Fundación Genoma España and with the contributions of the PLAT KKBE project PIM2010PKB-00691.Peer reviewe