736 research outputs found

    Investigating the impact of additive manufacturing data exchange standards for re-distributed manufacturing

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    This is a post-peer-review, pre-copy edit version of an article published in Progress in Additive Manufacturing. The final authenticated version is available online at: https://link.springer.com/article/10.1007%2Fs40964-019-00085-7The paradigm shift towards a decentralised approach of cloud manufacturing requires tighter standardisation and efficient interfaces between additive manufacturing (AM) data and production. In parallel with technology advancements, it is important to consider the digital chain of information. Although a plethora of AM formats exist, only some are commonly used for data transfer. None of these AM data transfer standards specifically addresses the needs of the re-distributed manufacturing (RDM) landscape. The purpose of this study is to identify the required features for AM data transfer standards to support a RDM landscape. The study examined the data flow from CAD to AM and reviewed established shortcomings of existing data exchange standards such as STL. After identifying the data exchange standards for AMF, 3MF, STEP and STEP-NC as promising replacements for STL, their premises, objectives, contributions and advantages were reviewed. The role of AM to support RDM by overcoming tooling costs and the associated need for economies of scale was also reviewed. Focus group interviews and surveys were conducted with AM and RDM experts from industry and academia and the participants’ accounts were analysed for common themes and narratives. Finally, the suitability of existing data transfer formats was examined by compiling existing and expected standard features and having them rated by AM experts. The study showed that STEP-NC and AMF standards are ahead in implementing the most highly valued data transfer features. Open standards are also expected to further facilitate innovation in AM. The survey also identified that the top five features deemed most important by the participants for data exchange formats for RDM were regular internal structures/lattices, manufacturing tolerances, geometric representation, curvature representation, and surface structures. This study has contributed towards evaluating existing standards and their future development and adoption. It is hoped that the results will benefit policy makers and industry leaders to be aware of the importance of data exchange standards for AM so as to pave a clear roadmap for the Digital Economy in a RDM landscape

    Measuring Coverage in MNCH:A Validation Study Linking Population Survey Derived Coverage to Maternal, Newborn, and Child Health Care Records in Rural China

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    Accurate data on coverage of key maternal, newborn, and child health (MNCH) interventions are crucial for monitoring progress toward the Millennium Development Goals 4 and 5. Coverage estimates are primarily obtained from routine population surveys through self-reporting, the validity of which is not well understood. We aimed to examine the validity of the coverage of selected MNCH interventions in Gongcheng County, China.We conducted a validation study by comparing women's self-reported coverage of MNCH interventions relating to antenatal and postnatal care, mode of delivery, and child vaccinations in a community survey with their paper- and electronic-based health care records, treating the health care records as the reference standard. Of 936 women recruited, 914 (97.6%) completed the survey. Results show that self-reported coverage of these interventions had moderate to high sensitivity (0.57 [95% confidence interval (CI): 0.50-0.63] to 0.99 [95% CI: 0.98-1.00]) and low to high specificity (0 to 0.83 [95% CI: 0.80-0.86]). Despite varying overall validity, with the area under the receiver operating characteristic curve (AUC) ranging between 0.49 [95% CI: 0.39-0.57] and 0.90 [95% CI: 0.88-0.92], bias in the coverage estimates at the population level was small to moderate, with the test to actual positive (TAP) ratio ranging between 0.8 and 1.5 for 24 of the 28 indicators examined. Our ability to accurately estimate validity was affected by several caveats associated with the reference standard. Caution should be exercised when generalizing the results to other settings.The overall validity of self-reported coverage was moderate across selected MNCH indicators. However, at the population level, self-reported coverage appears to have small to moderate degree of bias. Accuracy of the coverage was particularly high for indicators with high recorded coverage or low recorded coverage but high specificity. The study provides insights into the accuracy of self-reports based on a population survey in low- and middle-income countries. Similar studies applying an improved reference standard are warranted in the future

    Educational outreach to general practitioners reduces children's asthma symptoms: a cluster randomised controlled trial

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    <p>Abstract</p> <p>Background</p> <p>Childhood asthma is common in Cape Town, a province of South Africa, but is underdiagnosed by general practitioners. Medications are often prescribed inappropriately, and care is episodic. The objective of this study is to assess the impact of educational outreach to general practitioners on asthma symptoms of children in their practice.</p> <p>Methods</p> <p>This is a cluster randomised trial with general practices as the unit of intervention, randomisation, and analysis. The setting is Mitchells Plain (population 300,000), a dormitory town near Cape Town. Solo general practitioners, without nurse support, operate from storefront practices. Caregiver-reported symptom data were collected for 318 eligible children (2 to 17 years) with moderate to severe asthma, who were attending general practitioners in Mitchells Plain. One year post-intervention follow-up data were collected for 271 (85%) of these children in all 43 practices.</p> <p>Practices randomised to intervention (21) received two 30-minute educational outreach visits by a trained pharmacist who left materials describing key interventions to improve asthma care. Intervention and control practices received the national childhood asthma guideline. Asthma severity was measured in a parent-completed survey administered through schools using a symptom frequency and severity scale. We compared intervention and control group children on the change in score from pre-to one-year post-intervention.</p> <p>Results</p> <p>Symptom scores declined an additional 0.84 points in the intervention vs. control group (on a nine-point scale. p = 0.03). For every 12 children with asthma exposed to a doctor allocated to the intervention, one extra child will have substantially reduced symptoms.</p> <p>Conclusion</p> <p>Educational outreach was accepted by general practitioners and was effective. It could be applied to other health care quality problems in this setting.</p

    Constraints on Automorphic Forms of Higher Derivative Terms from Compactification

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    By dimensionally reducing the higher derivative corrections of ten-dimensional IIB theory on a torus we deduce constraints on the E_{n+1} automorphic forms that occur in d=10-n dimensions. In particular we argue that these automorphic forms involve the representation of E_{n+1} with fundamental weight \lambda^{n+1}, which is also the representation to which the string charges in d dimensions belong. We also consider a similar calculation for the reduction of higher derivative terms in eleven-dimensional M-theory.Comment: Minor corrections, to appear in JHE

    Higher derivative type II string effective actions, automorphic forms and E11

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    By dimensionally reducing the ten-dimensional higher derivative type IIA string theory effective action we place constraints on the automorphic forms that appear in the effective action in lower dimensions. We propose a number of properties of such automorphic forms and consider the prospects that E11 can play a role in the formulation of the higher derivative string theory effective action.Comment: 34 page

    Long-lived neutral-kaon flux measurement for the KOTO experiment

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    The KOTO (K0K^0 at Tokai) experiment aims to observe the CP-violating rare decay KLπ0ννˉK_L \rightarrow \pi^0 \nu \bar{\nu} by using a long-lived neutral-kaon beam produced by the 30 GeV proton beam at the Japan Proton Accelerator Research Complex. The KLK_L flux is an essential parameter for the measurement of the branching fraction. Three KLK_L neutral decay modes, KL3π0K_L \rightarrow 3\pi^0, KL2π0K_L \rightarrow 2\pi^0, and KL2γK_L \rightarrow 2\gamma were used to measure the KLK_L flux in the beam line in the 2013 KOTO engineering run. A Monte Carlo simulation was used to estimate the detector acceptance for these decays. Agreement was found between the simulation model and the experimental data, and the remaining systematic uncertainty was estimated at the 1.4\% level. The KLK_L flux was measured as (4.183±0.017stat.±0.059sys.)×107(4.183 \pm 0.017_{\mathrm{stat.}} \pm 0.059_{\mathrm{sys.}}) \times 10^7 KLK_L per 2×10142\times 10^{14} protons on a 66-mm-long Au target.Comment: 27 pages, 16 figures. To be appeared in Progress of Theoretical and Experimental Physic

    Dental management considerations for the patient with an acquired coagulopathy. Part 1: Coagulopathies from systemic disease

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    Current teaching suggests that many patients are at risk for prolonged bleeding during and following invasive dental procedures, due to an acquired coagulopathy from systemic disease and/or from medications. However, treatment standards for these patients often are the result of long-standing dogma with little or no scientific basis. The medical history is critical for the identification of patients potentially at risk for prolonged bleeding from dental treatment. Some time-honoured laboratory tests have little or no use in community dental practice. Loss of functioning hepatic, renal, or bone marrow tissue predisposes to acquired coagulopathies through different mechanisms, but the relationship to oral haemostasis is poorly understood. Given the lack of established, science-based standards, proper dental management requires an understanding of certain principles of pathophysiology for these medical conditions and a few standard laboratory tests. Making changes in anticoagulant drug regimens are often unwarranted and/or expensive, and can put patients at far greater risk for morbidity and mortality than the unlikely outcome of postoperative bleeding. It should be recognised that prolonged bleeding is a rare event following invasive dental procedures, and therefore the vast majority of patients with suspected acquired coagulopathies are best managed in the community practice setting
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