3,923 research outputs found

    Design approach for a microprocessor-based GPS time transfer receiver

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    The design concept and characteristics of a self-contained microprocessor-based Global Positioning System time transfer receiver is described. A prototype of this unit is currently in the test phase. It employs two-bit digital baseband correlation rather than analog IF correlation of the signals with the reference code. The correlator, numerically controlled oscillators and code generator are implemented in a special-purpose digital signal processor. The time is recovered in the digital code tracking loop, and final corrections are applied in the control processor. Other features of this design are: (1) drift-free digital mechanization; (2) high reliability of digital circuits; (3) flexible control capability of the microprocessor; and (4) potential for a high degree of digital VLSI chip development leading to compact, low-cost units

    Intervening with persons experiencing mental illness and substance use: Patient perceptions of helpful care during psychiatric hospitalization

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    Background30 - 50% of people with mental illness also experience a substance use problem or concurrent disorder (CD). This dual diagnosis is associated with complex health and social problems, high suicide risk and poor longterm outcomes. Persons with CD have unique needs which present significant challenges for health providers during psychiatric hospitalization. While hospital personnel play a significant role in promoting health and well-being, what “helpful care” means to persons with CD during psychiatric hospitalization remains unexplored, and the health benefits unknown. Research QuestionWhat actual and/or potential interventions, attitudes, actions, and behaviours are perceived as “helpful” by persons with CD during psychiatric hospitalization?MethodsQualitative-descriptive design; individual, semi-structured audio-recorded interviews with 12 inpatient adults diagnosed with CD.ResultsParticipants reported both beneficial and harmful practices.Examples of helpful interventions occurred within 3 distinct areas: 1) building a therapeutic relationship; 2) engaging in health-promoting activities within a healing environment; 3) managing substance use in tandem with mental illness. ImplicationsFindings highlight the importance of relational interventions for persons with CD. This includes actions aimed at tailoring care to fit each individual while offering interpersonal approaches, attitudes and behaviours that are collaborative, caring and respectful. Helpful activities include assisting with daily care, advocating for time outside, offering teaching and learning sessions and facilitating discharge. There is an urgent call to prevent harmful practices and to understand and promote interventions consistent with whole person care for hospitalized clients with CD

    The NorduGrid architecture and tools

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    The NorduGrid project designed a Grid architecture with the primary goal to meet the requirements of production tasks of the LHC experiments. While it is meant to be a rather generic Grid system, it puts emphasis on batch processing suitable for problems encountered in High Energy Physics. The NorduGrid architecture implementation uses the \globus{} as the foundation for various components, developed by the project. While introducing new services, the NorduGrid does not modify the Globus tools, such that the two can eventually co-exist. The NorduGrid topology is decentralized, avoiding a single point of failure. The NorduGrid architecture is thus a light-weight, non-invasive and dynamic one, while robust and scalable, capable of meeting most challenging tasks of High Energy Physics.Comment: Talk from the 2003 Computing in High Energy Physics and Nuclear Physics (CHEP03), La Jolla, Ca, USA, March 2003, 9 pages,LaTeX, 4 figures. PSN MOAT00

    Atlas Data-Challenge 1 on NorduGrid

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    The first LHC application ever to be executed in a computational Grid environment is the so-called ATLAS Data-Challenge 1, more specifically, the part assigned to the Scandinavian members of the ATLAS Collaboration. Taking advantage of the NorduGrid testbed and tools, physicists from Denmark, Norway and Sweden were able to participate in the overall exercise starting in July 2002 and continuing through the rest of 2002 and the first part of 2003 using solely the NorduGrid environment. This allowed to distribute input data over a wide area, and rely on the NorduGrid resource discovery mechanism to find an optimal cluster for job submission. During the whole Data-Challenge 1, more than 2 TB of input data was processed and more than 2.5 TB of output data was produced by more than 4750 Grid jobs.Comment: Talk from the 2003 Computing in High Energy Physics and Nuclear Physics (CHEP03), La Jolla, Ca, USA, March 2003, 7 pages, 3 ps figure

    Velocity autocorrelation function of a Brownian particle

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    In this article, we present molecular dynamics study of the velocity autocorrelation function (VACF) of a Brownian particle. We compare the results of the simulation with the exact analytic predictions for a compressible fluid from [6] and an approximate result combining the predictions from hydrodynamics at short and long times. The physical quantities which determine the decay were determined from separate bulk simulations of the Lennard-Jones fluid at the same thermodynamic state point.We observe that the long-time regime of the VACF compares well the predictions from the macroscopic hydrodynamics, but the intermediate decay is sensitive to the viscoelastic nature of the solvent.Comment: 7 pages, 6 figure

    Simulation numérique des grandes échelles dans la convection forcée d'un fluide d'Ostwald de Waele en conduite cylindrique : effet du nombre de Prandtl

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    National audienceLe transfert de chaleur dans la convection forcée turbulente d’un fluide d’Oswald de Waele s’écoulant dans une conduite cylindrique horizontale, chauffée par une densité de flux de chaleur uniforme imposée à la paroi, est analysé à l’aide de simulations numériques des grandes échelles. Le modèle sous-maille de Smagorinsky non-newtonien d’Ohta et Miyashita [J. Non-Newtonian Fluid Mech, 2014] est mis en oeuvre, pour un nombre de Reynolds Re=4000, et différentes valeurs de l’indice d’écoulement (0.75≤n≤1.2) et du nombre de Prandtl (1≤Pr≤100). L’influence de Pr sur diverses statistiques est plus particulièrement étudiée

    Supramolecular aggregation in dithia-arsoles: chlorides, cations and N-centred paddlewheels

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    The benzo-fused dithia-chloro-arsole derivative C6H4S2AsCl (1) is found to crystallise in the triclinic space group P[1 with combining macron] with 17 molecules in the asymmetric unit whereas the tolyl derivative, MeC6H3S2AsCl (2) is polymorphic with the α-phase crystallising in the monoclinic space group P21/c with a single molecule in the asymmetric unit and the β-phase adopting a triclinic structure with two molecules in the asymmetric unit. Reaction of these dithia-chloro-arsole derivatives with LiN(SiMe3)2 in a 3 : 1 mole ratio afforded the unique paddlewheel structure (MeC6H4S2As)3N (4)

    Using Resonances to Control Chaotic Mixing within a Translating and Rotating Droplet

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    Enhancing and controlling chaotic advection or chaotic mixing within liquid droplets is crucial for a variety of applications including digital microfluidic devices which use microscopic ``discrete'' fluid volumes (droplets) as microreactors. In this work, we consider the Stokes flow of a translating spherical liquid droplet which we perturb by imposing a time-periodic rigid-body rotation. Using the tools of dynamical systems, we have shown in previous work that the rotation not only leads to one or more three-dimensional chaotic mixing regions, in which mixing occurs through the stretching and folding of material lines, but also offers the possibility of controlling both the size and the location of chaotic mixing within the drop. Such a control was achieved through appropriate tuning of the amplitude and frequency of the rotation in order to use resonances between the natural frequencies of the system and those of the external forcing. In this paper, we study the influence of the orientation of the rotation axis on the chaotic mixing zones as a third parameter, as well as propose an experimental set up to implement the techniques discussed.Comment: 15 pages, 6 figure

    Internet-of-Things-Enabled Smart Bed Rail for Application in Hospital Beds

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    This article presents an atypical offline based LoRaWAN application for use in hospital settings, where the ability to maintain network connectivity during internet connection disruption is paramount. A prototype bed rail is demonstrated, providing advanced functionality compared to traditional bed rails. The manufactured prototype provides data to a nurses station reliably and operates under battery backup. The power consumption of the system under different transmission intervals was tested, allowing appropriate battery sizing for different applications to be specified accurately. It is expected that a single LoRaWAN gateway will be able to cover bed rails across an entire modern hospital, allowing minimal infrastructure cost to implement the device or application in a rapidly deployed field hospital.</jats:p
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