352 research outputs found

    Industry 4.0 and the human factor : A systems framework and analysis methodology for successful development

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    The fourth industrial revolution we currently witness changes the role of humans in operations systems. Although automation and assistance technologies are becoming more prevalent in production and logistics, there is consensus that humans will remain an essential part of operations systems. Nevertheless, human factors are still underrepresented in this research stream resulting in an important research and application gap. This article first exposes this gap by presenting the results of a focused content analysis of earlier research on Industry 4.0. To contribute to closing this gap, it then develops a conceptual framework that integrates several key concepts from the human factors engineering discipline that are important in the context of Industry 4.0 and that should thus be considered in future research in this area. The framework can be used in research and development to systematically consider human factors in Industry 4.0 designs and implementations. This enables the analysis of changing demands for humans in Industry 4.0 environments and contributes towards a successful digital transformation that avoid the pitfalls of innovation performed without attention to human factors. The paper concludes with highlighting future research directions on human factors in Industry 4.0 as well as managerial implications for successful applications in practice

    The Optical-Near-IR Spectrum of the M87 Jet From HST Observations

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    We present 1998 HST observations of M87 which yield the first single-epoch optical and radio-optical spectral index images of the jet at 0.150.15'' resolution. We find 0.67 \approx 0.67, comparable to previous measurements, and 0.9 \approx 0.9 (FνναF_\nu \propto \nu^{-\alpha}), slightly flatter than previous workers. Reasons for this discrepancy are discussed. These observations reveal a large variety of spectral slopes. Bright knots exhibit flatter spectra than interknot regions. The flattest spectra (αo0.50.6\alpha_o \sim 0.5-0.6; comparable to or flatter than αro\alpha_{ro}) are found in two inner jet knots (D-East and HST-1) which contain the fastest superluminal components. In knots A, B and C, αo\alpha_o and αro\alpha_{ro} are essentially anti-correlated. Near the flux maxima of knots HST-1 and F, changes in αro\alpha_{ro} lag changes in αo\alpha_o, but in knots D and E, the opposite relationship is observed. This is further evidence that radio and optical emissions in the M87 jet come from substantially different physical regions. The delays observed in the inner jet are consistent with localized particle acceleration, with tacc<<tcoolt_{acc} << t_{cool} for optically emitting electrons in knots HST-1 and F, and tacctcoolt_{acc} \sim t_{cool} for optically emitting electrons in knots D and E. Synchrotron models yield \nu_B \gsim 10^{16} Hz for knots D, A and B, and somewhat lower values, νB10151016\nu_B \sim 10^{15}- 10^{16} Hz, in other regions. If X-ray emissions from knots A, B and D are co-spatial with optical and radio emission, we can strongly rule out the ``continuous injection'' model. Because of the short lifetimes of X-ray synchrotron emitting particles, the X-ray emission likely fills volumes much smaller than the optical emission regions.Comment: Text 17 pages, 3 Tables, 11 figures, accepted by Ap

    Methodological Issues in Evaluating Workplace Interventions to Reduce Work-related Musculoskeletal Disorders Through Mechanical Exposure Reduction

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    Researchers of work-related musculoskeletal disorders are increasingly asked about the evidentiary base for mechanical exposure reductions. Mixed messages can arise from the different disciplinary cultures of evidence, and these mixed messages make different sets of findings incommensurate. Interventions also operate at different levels within workplaces and result in different intensities of mechanical exposure reduction. Heterogeneity in reporting intervention processes and in measuring relevant outcomes makes the synthesis of research reports difficult. As a means of synthesizing the current understanding of measures, this paper describes a set of intervention and observation nodes for which relevant workplace indicators prior to, during, and after mechanical exposure reduction can provide useful information. On the basis of this path of impacts from exposure reduction, an approach to the evaluation of multilevel ergonomic interventions is described that can assist fellow researchers in producing evidence relevant to the challenges faced by workplace parties and policy makers

    Human mobility at Tell Atchana (Alalakh), Hatay, Turkey during the 2nd millennium BC: Integration of isotopic and genomic evidence

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    The Middle and Late Bronze Age, a period roughly spanning the 2nd millennium BC (ca. 2000–1200 BC) in the Near East, is frequently referred to as the first ‘international age’, characterized by intense and far-reaching contacts between different entities from the eastern Mediterranean to the Near East and beyond. In a large-scale tandem study of stable isotopes and ancient DNA of individuals excavated at Tell Atchana (Alalakh, located in Hatay, Turkey), we explored the role of mobility at the capital of a regional kingdom, named Mukish during the Late Bronze Age, which spanned the Amuq Valley and some areas beyond. We generated strontium and oxygen isotope data from dental enamel for 53 individuals and 77 individuals, respectively, and added ancient DNA data of 10 newly sequenced individuals to a dataset of 27 individuals published in 2020. Additionally, we improved the DNA coverage of one individual from this 2020 dataset. The DNA data revealed a very homogeneous gene pool. This picture of an overwhelmingly local ancestry was consistent with the evidence of local upbringing in most of the individuals indicated by the isotopic data, where only five were found to be non-local. High levels of contact, trade, and exchange of ideas and goods in the Middle and Late Bronze Ages, therefore, seem not to have translated into high levels of individual mobility detectable at Tell Atchana

    Diverse sediment microbiota shape methane emission temperature sensitivity in Arctic lakes

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    Northern post-glacial lakes are significant, increasing sources of atmospheric carbon through ebullition (bubbling) of microbially-produced methane (CH4) from sediments. Ebullitive CH4 flux correlates strongly with temperature, reflecting that solar radiation drives emissions. However, here we show that the slope of the temperature-CH4 flux relationship differs spatially across two post-glacial lakes in Sweden. We compared these CH4 emission patterns with sediment microbial (metagenomic and amplicon), isotopic, and geochemical data. The temperature-associated increase in CH4 emissions was greater in lake middles—where methanogens were more abundant—than edges, and sediment communities were distinct between edges and middles. Microbial abundances, including those of CH4-cycling microorganisms and syntrophs, were predictive of porewater CH4 concentrations. Results suggest that deeper lake regions, which currently emit less CH4 than shallower edges, could add substantially to CH4 emissions in a warmer Arctic and that CH4 emission predictions may be improved by accounting for spatial variations in sediment microbiota

    Structure and Evolution of the Lunar Procellarum Region as Revealed by GRAIL Gravity Data

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    The Procellarum region is a broad area on the nearside of the Moon that is characterized by low elevations, thin crust, and high surface concentrations of the heat-producing elements uranium, thorium, and potassium. The Procellarum region has been interpreted as an ancient impact basin approximately 3200 km in diameter, though supporting evidence at the surface would have been largely obscured as a result of the great antiquity and poor preservation of any diagnostic features. Here we use data from the Gravity Recovery and Interior Laboratory (GRAIL) mission to examine the subsurface structure of Procellarum. The Bouguer gravity anomalies and gravity gradients reveal a pattern of narrow linear anomalies that border the Procellarum region and are interpreted to be the frozen remnants of lava-filled rifts and the underlying feeder dikes that served as the magma plumbing system for much of the nearside mare volcanism. The discontinuous surface structures that were earlier interpreted as remnants of an impact basin rim are shown in GRAIL data to be a part of this continuous set of quasi-rectangular border structures with angular intersections, contrary to the expected circular or elliptical shape of an impact basin. The spatial pattern of magmatic-tectonic structures bounding Procellarum is consistent with their formation in response to thermal stresses produced by the differential cooling of the province relative to its surroundings, coupled with magmatic activity driven by the elevated heat flux in the region
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