17 research outputs found

    VHDL-AMS modeling and simulation of a direct sequence spread spectrum (DS-SS) transmitter

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    Many recent standards in telecommunications field are based on CDMA spread spectrum transmissions. In this paper, we describe a methodology for top-down design, modeling, and simulation of CDMA transmitter system using hardware description language VHDL-AMS. Details of VHDL-AMS implementation for each elementary block are shown. This paper together with the developed library of CDMA transmitter blocks are targeted towards engineers who work on behavioral modeling and simulation of complete CDMA systems using hardware description languages

    ModĂ©lisation (VHDL), simulation et optimisation de l’architecture du rĂ©cepteurCDMA « Poursuite et Synchronisation »

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    Cet article prĂ©sente une amĂ©lioration des Ă©tages de synchronisation et de poursuite d’un systĂšme de communication utilisant l’étalement de spectre par sĂ©quence directe, dans le but de rĂ©duire le temps d’acquisition et d’augmenter le gain en traitement qui dĂ©pend de la longueur de la sĂ©quence et des performances de la poursuite. Le travail consiste alors Ă  dĂ©velopper une DLL spĂ©cifique cohĂ©rente permettant de gĂ©nĂ©rer un code de dĂ©sĂ©talement synchronisĂ© indĂ©pendamment du dĂ©phasage de la porteuse.Nous proposons un modĂšle VHDL complet du rĂ©cepteur CDMA oĂč l'accent est mis sur les organes de synchronisation numĂ©riques synthĂ©tisables en vue d’une implĂ©mentation sur FPGA

    Stratégie de Coopération entre les réseaux LTE-Radio cognitif en utilisant les technologies MIMO

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    Dans le rĂ©seau LTE avec la large bande, le dĂ©bit est Ă©levĂ© et le nombre d’utilisateurs est important, mais avec un risque accru d'interfĂ©rence et de surcharge au niveau du EnodeB [2]. Pour rĂ©pondre Ă  la demande croissante de spectre radioĂ©lectrique [5], on va prĂ©senter dans ce travail un scĂ©nario de coopĂ©ration entre le EnodeB et un systĂšme cognitif (RC).En utilisant un algorithme coopĂ©ratif de gestion de spectre au niveau du RC, on a menĂ© une Ă©tude comparative au terme de la capacitĂ© du EnodeB avec et sans coopĂ©ration. Les simulations rĂ©alisĂ©es donnent des rĂ©sultats satisfaisants

    Global survey of the roles, satisfaction, and barriers of home healthcare nurses on the provision of palliative care

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    Background: the World Health Assembly urges members to build palliative care (PC) capacity as an ethical imperative. Nurses provide PC services in a variety of settings, including the home and may be the only health care professional able to access some disparate populations. Identifying current nursing services, resources, and satisfaction and barriers to nursing practice are essential to build global PC capacity. Objective: to globally examine home health care nurses' practice, satisfaction, and barriers, regarding existing palliative home care provision. Design: needs assessment survey. Setting/Subjects: five hundred thirty-two home health care nurses in 29 countries. Measurements: a needs assessment, developed through literature review and cognitive interviewing. Results: nurses from developing countries performed more duties compared with those from high-income countries, suggesting a lack of resources in developing countries. Significant barriers to providing home care exist: personnel shortages, lack of funding and policies, poor access to end-of-life or hospice services, and decreased community awareness of services provided. Respondents identified lack of time, funding, and coverages as primary educational barriers. In-person local meetings and online courses were suggested as strategies to promote learning. Conclusions: it is imperative that home health care nurses have adequate resources to build PC capacity globally, which is so desperately needed. Nurses must be up to date on current evidence and practice within an evidence-based PC framework. Health care policy to increase necessary resources and the development of a multifaceted intervention to facilitate education about PC is indicated to build global capacity

    Age and date for early arrival of the Acheulian in Europe (Barranc de la Boella, la Canonja, Spain)

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    The first arrivals of hominin populations into Eurasia during the Early Pleistocene are currently considered to have occurred as short and poorly dated biological dispersions. Questions as to the tempo and mode of these early prehistoric settlements have given rise to debates concerning the taxonomic significance of the lithic assemblages, as trace fossils, and the geographical distribution of the technological traditions found in the Lower Palaeolithic record. Here, we report on the Barranc de la Boella site which has yielded a lithic assemblage dating to ,1 million years ago that includes large cutting tools (LCT). We argue that distinct technological traditions coexisted in the Iberian archaeological repertoires of the late Early Pleistocene age in a similar way to the earliest sub-Saharan African artefact assemblages. These differences between stone tool assemblages may be attributed to the different chronologies of hominin dispersal events. The archaeological record of Barranc de la Boella completes the geographical distribution of LCT assemblages across southern Eurasia during the EMPT (Early-Middle Pleistocene Transition, circa 942 to 641 kyr). Up to now, chronology of the earliest European LCT assemblages is based on the abundant Palaeolithic record found in terrace river sequences which have been dated to the end of the EMPT and later. However, the findings at Barranc de la Boella suggest that early LCT lithic assemblages appeared in the SW of Europe during earlier hominin dispersal episodes before the definitive colonization of temperate Eurasia took place.The research at Barranc de la Boella has been carried out with the financial support of the Spanish Ministerio de EconomıŽa y Competitividad (CGL2012- 36682; CGL2012-38358, CGL2012-38434-C03-03 and CGL2010-15326; MICINN project HAR2009-7223/HIST), Generalitat de Catalunya, AGAUR agence (projects 2014SGR-901; 2014SGR-899; 2009SGR-324, 2009PBR-0033 and 2009SGR-188) and Junta de Castilla y LeoÂŽn BU1004A09. Financial support for Barranc de la Boella field work and archaeological excavations is provided by the Ajuntament de la Canonja and Departament de Cultura (Servei d’Arqueologia i Paleontologia) de la Generalitat de Catalunya. A. Carrancho’s research was funded by the International Excellence Programme, Reinforcement subprogramme of the Spanish Ministry of Education. I. Lozano-FernaÂŽndez acknowledges the pre-doctoral grant from the FundacioÂŽn Atapuerca. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Evolution of GPR regulation in the control of spindle positioning for two Caenorhabditis species embryos

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    International audienceno abstrac

    Le pneumocytome sclérosant : une tumeur rare et apparemment bénigne

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    International audienceIntroduction: Sclerosing pneumocytoma is a benign and rare lung tumor affecting epithelial cells. In most cases, patients are asymptomatic and the diagnosis is made on an X ray or a CT scan performed for other enquiry. Sex ratio favors women. Epidemiological studies report that middle-aged Asian women are more frequently affected. Radiological investigations find a solitary nodule or a mass with peripheric localization. When performed, histological analysis shows a tumor composed of at least two of the four following architectures: papillary, sclerosing, hemangiomatous and solid, with two types of cells that can be round or cubic cells.Cases report: We report two cases of multiple sclerosing pneumocytoma in two caucasien men. The first patient was asymptomatic, the second complain from moderate dyspnea. A wedge resection was performed in both, allowing diagnosis. Anatomopathology revealed respectively a predominant sclerosing and solid architecture and a sclerosing and papillary architecture. There was no progression of the other concomitant nodules after three years follow-up.Conclusion: Pneumocytoma is a benign, slow-growing tumor with good prognosis
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