99 research outputs found

    Communication: Studies of the Lennard-Jones fluid in 2, 3, and 4 dimensions highlight the need for a liquid-state 1/d expansion

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    The recent theoretical prediction by Maimbourg and Kurchan [arXiv:1603.05023] that for regular pair-potential systems the virial potential-energy correlation coefficient increases towards unity as the dimension dd goes to infinity is investigated for the standard 12-6 Lennard-Jones fluid. This is done by computer simulations for d=2,3,4d=2,3,4 going from the critical point along the critical isotherm/isochore to higher density/temperature. In all cases the virial potential-energy correlation coefficient increases significantly. For a given density and temperature relative to the critical point, with increasing number of dimension the Lennard-Jones system conforms better to the hidden-scale-invariance property characterized by high virial potential-energy correlations (a property that leads to the existence of isomorphs in the thermodynamic phase diagram, implying that it becomes effectively one-dimensional in regard to structure and dynamics). The present paper also gives the first numerical demonstration of isomorph invariance of structure and dynamics in four dimensions. Our findings emphasize the need for a universally applicable 1/d1/d expansion in liquid-state theory; we conjecture that the systems known to obey hidden scale invariance in three dimensions are those for which the yet-to-be-developed 1/d1/d expansion converges rapidly

    Integration of industrial IoT architectures for dynamic scheduling

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    Technology advancement in smart sensors, cloud computing, and decision support systems is pressuring the industry to adopt more flexible data-based solutions. One of the areas that can benefit from this progress is dynamic scheduling, which can improve production efficiency by tracking resource availability, job changes, and user commands. Challenges include setting triggers through the simultaneous integration of information from cloud-based enterprise databases and operational sources in the Industrial Internet of Things (IIoT). This paper proposes an integrated Information Technology - Operational Technology solution to support dynamic scheduling and rescheduling operations in a personalized production environment. It presents an implementation to a real-world application: an analytical quality control laboratory in the pharmaceutical industry. The resulting integration of intelligent sensors and business events in a fog computing architecture allows the generation of rescheduling triggers to specific online events. This paper focus on the definition of the online events affecting the operations and the cloud-fog-edge IIoT architecture used to support the implementation, and on the rescheduling triggers. The optimized reschedule of the use case shows that moving the computation closer to the cloud improves the CPU run time for larger instances. However, the combined CPU run time with the data exchange and querying introduces a non-negligible communication delay for smaller instances. In situations where fast scheduling solutions are required, fog computing near the edge is the best approach. On the other hand, for larger-size instances, moving the computation closer to the cloud is the recommended approach

    Excess-entropy scaling in supercooled binary mixtures

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    Supercooled liquids near the glass transition show remarkable non-Arrhenius transport phenomena, whose origin is yet to be clarified. Here, the authors use GPU molecular dynamics simulations for various binary mixtures in the supercooled regime to show the validity of a quasiuniversal excess-entropy scaling relation for viscosity and diffusion

    Pandemic influenza preparedness: The critical role of the syringe

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    In the face of an almost unprecedented threat of a global pandemic of influenza it is imperative that stockpiling of appropriate drugs and devices begin now. One vital device is an appropriate syringe for delivering vaccine. With the potential for millions to be infected and the vaccine supply severely stretched it is imperative that the syringe used to vaccinate waste as little vaccine as possible and thus allow for a maximum number of persons to be vaccinated. Our study tested seven leading candidate vaccine syringes for dosing accuracy, dose-capacity per vial, medication wastage and a battery of ergonomic features. One device, the Flu+(TM) syringe, proved superior to the others in all important categories, possibly due to its low dead-space volume and its dosing accuracy. The data suggest that switching to this device from any of the others tested would provide between 2 and 19% additional vaccine doses per vial if the current 10-dose vials are used. Extrapolations from this data suggest that many thousands to millions of additional persons could be vaccinated in mass campaigns. Use of a syringe of this type, and the vaccine savings that would accrue, would likely be important in reducing morbidity and mortality in the event of a pandemic of influenza. (c) 2006 Elsevier Ltd. All rights reserved

    Abdominal adiposity is an early marker of pulmonary function impairment: Findings from a Mediterranean Italian female cohort

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    Background and aims: Abdominal adiposity may influence the respiratory function, especially in women. The aim of this prospective study is to evaluate the predictive role of body mass index (BMI) and waist circumference (WC) on lung function in healthy women. Methods and results: In 600 women randomly selected from the cohort of the "Progetto ATENA," anthropometric measures such as BMI, WC, and weight gain were recorded at baseline, and the spirometric parameters were measured 10 years later. The percentage values of forced expiratory volume in 1 s (FEV1%) and forced vital capacity (FVC%) and the ratio of FEV1/FVC were compared with the anthropometric measures after adjustment for several variables measured at baseline such as age, height, socioeconomic status, smoking habits, and history of respiratory allergies grouped in a basal model.WC is significantly associated with a decreased FVC (p = 0.008) and an increased ratio of FEV1/FVC (p = 0.031) after adjustment for the covariates of the basal model. The association between BMI and spirometric parameters reaches borderline significance only with the ratio of FEV1/FVC (p = 0.052). Conclusions: We suggest measuring both BMI and WC to assess the risk of future respiratory impairment
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