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81.
Computers are now widely used by children. Tablet computers are becoming widely available and promoted for use by school children. The primary objective of this study was to compare the posture and muscle activity of children using a tablet computer to the posture and muscle activity of children using a desktop computer and paper technology. Eighteen children (mean age 5.6 years) performed a colouring-in task in tablet, desktop and paper conditions. 3-D posture and muscle activity around the neck and shoulder was assessed. Tablet computer use was similar to paper use, with less neutral spinal posture, more elevated scapular posture and greater upper trapezius and cervical erector spinae activity. This was offset by greater variability of posture and muscle activity. Tablet computer use clearly results in different musculoskeletal stresses than desktop computer use. Computer use guidelines need to be appropriate to traditional and emerging technologies. Tablet computers are being promoted for use by adults and children. However, the physical impact of using this type of technology is not known. The findings of this study provide the first tablet-specific evidence to inform guidelines on wise use of tablet computers by children.  相似文献   
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Office workers perform tasks using different information and communication technologies (ICT) involving various postures. Adequate variation in postures and muscle activity is generally believed to protect against musculoskeletal complaints, but insufficient information exists regarding the effect on postural variation of using different ICT. Thus, this study among office workers aimed to determine and compare postures and postural variation associated with using distinct types of ICT. Upper arm, head and trunk postures of 24 office workers were measured with the Physiometer® over a whole day in their natural work and away-from-work environments. Postural variation was quantified using two indices: APDF(90-10) and EVA(sd). Various ICT had different postural means and variation. Paper-based tasks had more non-neutral, yet also more variable postures. Electronics-based tasks had more neutral postures, with less postural variability. Tasks simultaneously using paper- and electronics-based ICT had least neutral and least variable postures. Tasks without ICT usually had the most posture variability. Interspersing tasks involving different ICT could increase overall exposure variation among office workers and may thus contribute to musculoskeletal risk reduction.  相似文献   
84.
A participative ergonomics approach to reducing injuries associated with manual tasks is widely promoted; however only limited evidence from uncontrolled trials has been available to support the efficacy of such an approach. This paper reports on a randomized and controlled trial of PErforM, a participative ergonomics intervention designed to reduce the risks of injury associated with manual tasks. One hundred and seventeen small to medium sized food, construction, and health workplaces were audited by government inspectors using a manual tasks risk assessment tool (ManTRA). Forty-eight volunteer workplaces were then randomly assigned to Experimental and Control groups with the Experimental group receiving the PErforM program. Inspectors audited the workplaces again, 9 months following the intervention. The results showed a significant decrease in estimates of manual task risk and suggested better legal compliance in the Experimental group.  相似文献   
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This paper provides straightforward derivations of a wide variety of smoothing formulae which are associated with the Kalman filter. The smoothing operations are of perennial interest in the fields of communications engineering and signal processing. Recently they have begun to interest statisticians and economists. It is often asserted that it is tedious and difficult to derive the formulae. We show that this need not be so.  相似文献   
87.
This paper argues for the systematic development and presentation of evidence-based guidelines for appropriate use of computers by children. The currently available guidelines are characterised and a proposed conceptual model presented. Five principles are presented as a foundation to the guidelines. The paper concludes with a framework for the guidelines, key evidence for and against guidelines, and gaps in the available evidence, with the aim of facilitating further discussion.

Relevance to industry

The current generation of children in affluent countries will typically have over 10 years of computer experience before they enter the workforce. Consequently, the primary prevention of computer-related health disorders and the development of good productivity skills for the next generation of workers needs to occur during childhood.  相似文献   

88.
In their initial articulation of the direction of the CSCW field, scholars advanced an open-ended agenda. This continuing commitment to open-ness to different contexts and approaches is not, however, reflected in the contents of the major CSCW outlets. The field appears to privilege particular forms of cooperative work. We find many examples of what could be described as ‘localist studies’, restricted to particular settings and timeframes. This focus on the ‘here and now’ is particularly problematic when one considers the kinds of large-scale, integrated and interconnected workplace information technologies—or what we are calling Information Infrastructures—increasingly found within and across organisations today. CSCW appears unable (or unwilling) to grapple with these technologies—which were at the outset envisaged as falling within the scope of the field. Our paper hopes to facilitate greater CSCW attention to Information Infrastructures through offering a re-conceptualisation of the role and nature of ‘design’. Design within an Information Infrastructures perspective needs to accommodate non-local constraints. We discuss two such forms of constraint: standardisation (how local fitting entails unfitting at other sites) and embeddedness (the entanglement of one technology with other apparently unrelated ones). We illustrate these themes through introducing case material drawn on from a number of previous studies.  相似文献   
89.
Six hundred and seventeen isolates of Staphylococcus aureus from subclinical clinical mastitis cases in 63 dairy herds in Northern Ireland were typed using a set of 25 phages. Ninety-four per cent of the isolates were typable, with nine phages, predominantly from groups I and III, being responsible for almost all of the lysis. Although 68 phage patterns were found, six of them typed 47.2% of the isolates. One strain accounted for 14.7% of the isolates, but the largest number of strains (44) was restricted to individual farms. The epidemiological significance of these findings for on-farm mastitis control is discussed.  相似文献   
90.
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