891 research outputs found
Schema architecture and their relationships to transaction processing in distributed database systems
We discuss the different types of schema architectures which could be supported by distributed database systems, making a clear distinction between logical, physical, and federated distribution. We elaborate on the additional mapping information required in architecture based on logical distribution in order to support retrieval as well as update operations. We illustrate the problems in schema integration and data integration in multidatabase systems and discuss their impact on query processing. Finally, we discuss different issues relevant to the cooperation (or noncooperation) of local database systems in a heterogeneous multidatabase system and their relationship to the schema architecture and transaction processing
Wind flow through shrouded wind turbines
Wall pressure distributions and cross section flow distribution on wind turbine shroud designs, determined through static pressure measurements, were quantified in order to determine the most ideal design that could increase power output and reduce the radar cross section. Engineering and Expeditionary Warfare Center (EXWC) Port Hueneme provided four shroud designs in a 1:160 scale for analysis, including a model with a free-spinning wind turbine incorporated. These models were studied in the Naval Postgraduate School MAE wind tunnel. Tunnel velocity and model angle were varied. Additionally, static wall pressures and cross section flow were studied with the addition of a screen. The pressure measurements were collected by a Scanivalve pressure scanner from up to 90 taps drilled into the models at various locations as well as through an Aeroflow 5-hole probe, which took various measurements at multiple planes of each model. Flow visualization tests, including oil and tufts, were also conducted to help determine the aerodynamic efficiency of each model and identify any sign of flow separation. These studies provided a good evaluation of the efficiency of these models from a fluid flow perspective. While none of the models proved ideal, certain attributes, most importantly the geometry of a wind lens or flange on the shroud and a gradually diverging shape, proved to accelerate the flow through the duct.http://archive.org/details/windflowthroughs1094553045Lieutenant, United States NavyApproved for public release; distribution is unlimited
Effects of post-discharge counseling and medication utilization on short and long-term smoking cessation among hospitalized patients
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.Numerous studies have tested the effect of multicomponent post-discharge smoking cessation interventions on post-discharge smoking cessation, and many are effective. However, little is known regarding the relative efficacy of the different intervention components on short or long-term cessation. The present study is a secondary analysis (nâŻ=âŻ984) of a randomized controlled trial for hospitalized smokers that took place at two large hospitals in Kansas from 2011 to 2014. All study participants were offered post-discharge quitline services. Pharmacotherapy was recommended during bedside tobacco treatment. The study outcomes were self-reported cessation at 1-month and biochemically verified cessation at 6-months post-randomization. During the post-discharge period, 69% of participants completed at least one quitline call and 28% of participants reported using cessation pharmacotherapy. After controlling for known predictors of cessation among hospitalized smokers, both the number of total quitline calls completed post-discharge and use of cessation pharmacotherapy post-discharge were predictive of cessation at 1-month. After accounting for predictors of cessation and quitting at 1-month, total post-discharge quitline calls was associated with cessation at 6-months (OR [95% CI]âŻ=âŻ1.23 [1.12, 1.35], pâŻ<âŻ0.001) while post-discharge cessation pharmacotherapy use was not. The results suggest that both engagement in quitline services and use pharmacotherapy independently facilitate cessation beyond the influence of known clinical characteristics associated with cessation. Over the longer term, the effect of engaging in quitline services persists while the effect of pharmacotherapy diminishes. To optimize outcomes, future research should investigate methods to increase utilization of medications and promote sustained counseling engagement in order to sustain the effects of treatment during the post-discharge period.NIH National Heart, Lung, and Blood Institute (U01 HL105232
Ovo: um alimento nutritivo, saudĂĄvel e delicioso.
bitstream/item/166224/1/final8684.pdf1 Folder
Estimativa da emissão de gases de efeito estufa na produção de frangos de corte nos sistemas convencional e dark house.
bitstream/item/78905/1/Comunicado-504.pdfProjeto/Plano de Ação: 01.10.06.001
Sonho, desafio e tecnologia: 35 anos de contribuiçÔes da Embrapa SuĂnos e Aves.
bitstream/item/105259/1/publicacao-1z33f2s.pdfProjeto: 11.11.11.111
Persistent and Consistent Underpromotion of Women in Academic Medicine: It's Time to Make Some Waves
Barium isotopes in mid-ocean ridge hydrothermal vent fluids : a source of isotopically heavy Ba to the ocean
Funding: These field and related experimental studies were supported through US NSF grants: 0549547, 0751771, 0813861, 0961188 and 1736679 (WES).Mid-ocean ridge (MOR) hydrothermal vent fluids are enriched with dissolved barium, but due to barite (BaSO4) precipitation during mixing between Ba-bearing vent fluids and SO4-bearing seawater, the magnitude of hydrothermal Ba input to the ocean remains uncertain. Deep-ocean Ba isotopes show evidence for non-conservative behavior, which might be explained by input of isotopically heavy hydrothermal Ba. In this study we present the first Ba isotope data in mid-ocean ridge hydrothermal vent fluids and particles from systems on the Mid-Atlantic Ridge (Rainbow 36°N and TAG 26°N), the East Pacific Rise (EPR9â10°N and 13°N) and the Juan de Fuca Ridge (MEF and ASHES). The vent fluids display a wide range of dissolved Ba concentrations from 0.43 to 97.9âŻÎŒmol/kg and ÎŽ138/134Ba values from â0.26 to +0.91â°, but are modified relative to initial composition due to precipitation of barite. Calculated endmember vent fluid ÎŽ138/134Ba values, prior to barite precipitation, are between â0.17 and +0.09â°, consistent with the values observed in oceanic basalts and pelagic sediments. Water-rock interaction at depth in the oceanic crust appears to occur without Ba isotope fractionation. During subsequent venting and mixing with seawater, barite precipitation preferentially removes isotopically light Ba from vent fluids with a fractionation factor of Î138/134Bahyd-barite-fluidâŻ=âŻâ0.35âŻÂ±âŻ0.10â° (2SE, nâŻ=âŻ2). Based on knowledge of barite saturation and isotope fractionation during precipitation, the effective hydrothermal Ba component that mixes with seawater after barite precipitation has completed can be calculated: ÎŽ138/134BahydâŻ=âŻ+1.7âŻÂ±âŻ0.7â° (2SD). This value is isotopically heavier than deep ocean waters and may explain the observed non-conservative of Ba isotopes in deep waters. These new constraints on hydrothermal Ba compositions enable the hydrothermal input of Ba to Atlantic deep waters to be assessed at â3â9% of the observed Ba. Barium isotopes might be used as a tracer to reconstruct the history of hydrothermal Ba inputs and seawater SO4 concentrations in the past.PostprintPeer reviewe
Switching between dynamic states in intermediate-length Josephson junctions
The appearance of zero-field steps (ZFSâs) in the current-voltage characteristics of intermediate-length overlap-geometry Josephson tunnel junctions described by a perturbed sine-Gordon equation (PSGE) is associated with the growth of parametrically excited instabilities of the McCumber background curve (MCB). A linear stability analysis of a McCumber solution of the PSGE in the asymptotic linear region of the MCB and in the absence of magnetic field yields a Hillâs equation which predicts how the number, locations, and widths of the instability regions depend on the junction parameters. A numerical integration of the PSGE in terms of truncated series of time-dependent Fourier spatial modes verifies that the parametrically excited instabilities of the MCB evolve into the fluxon oscillations characteristic of the ZFSâs. An approximate analysis of the Fourier mode equations in the presence of a small magnetic field yields a field-dependent Hillâs equation which predicts that the major effect of such a field is to reduce the widths of the instability regions. Experimental measurements on Nb-NbxOy-Pb junctions of intermediate length, performed at different operating temperatures in order to vary the junction parameters and for various magnetic field values, verify the physical existence of switching from the MCB to the ZFSâs. Good qualitative, and in many cases quantitative, agreement between analytic, numerical, and experimental results is obtained
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