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861.
By using the self-developed triaxial servo-controlled seepage equipment for thermo-fluid-solid coupling of coal containing gas and the self-developed coal and gas outburst simulation test device, experiments to study the influence mechanism of gas seepage on coal and gas outburst disasters. The results show that: (i) gas seepage decreases the strength of coal containing gas and accelerates its failure process; (ii) under the same gas pressure, the confining pressure is larger, the more difficult the gas flows and the greater the intensity of coal containing gas is; (iii) in the process of coal and gas outburst, the greater the vertical ground stress is, the more powerful the outburst will be; (iv) the influence mechanism of gas seepage on coal and gas outburst disasters is as follows: firstly, gas seepage weakens the mechanical properties of coal body, which makes it much easier for coal and gas outburst to occur; secondly, on the same effect of external force, it will be easy to form a high gas pressure zone in the coal body under the difficult condition of gas seepage, and accumulate more gas compression energy, which is the energy source for coal and gas outburst, and it is also the main dynamic source to throw and grind the coal.  相似文献   
862.
This paper presents the design and the implementation of a methodology for measuring and improving safety culture at a nuclear power plant (NPP). The study has involved the completion of a pilot project aimed at seeing how to make use of the RADAR logic (Results, Approach, Deployment, Assessment and Review) of the EFQM model as a tool for the self assessment of safety culture in a nuclear power plant. The work was aimed at finding evidence of the safety culture that was in place at the plant and at identifying both the strengths of that culture and any areas in which it could be improved. The score obtained from an analysis of those strengths and areas for improvement has made it possible to prioritise the actions to be taken. The identification of perceptions and evidence, the agreement on the strong points and areas for improvement and the quantification of the safety culture have been performed by groups comprising volunteers who work at the NPP. The advantages of this methodology are assessed in the paper.  相似文献   
863.
PurposeThis study compared the healthcare utilization and costs for specific types of medical services among older adult women who currently drive and those who no longer drive.MethodsThis study included 347 women aged 65 or older who were either former (had stopped driving) or current drivers, randomly sampled from a large U.S. health plan to participate in a telephone survey, and who had automated health records with healthcare utilization and cost data. Bivariate analyses and generalized linear modeling were used to examine associations between driving status and healthcare utilization and costs.ResultsAdjusting for age, income, and marital status, former drivers were more likely than current drivers to use mental health care services (RR = 3.37; 95% CI: 1.03, 10.98). Former drivers also tended to use more inpatient (RR = 1.85; 95% CI: 0.88, 3.87) and emergency services (RR = 1.89; 95% CI: 0.96, 3.70), but results did not reach statistical significance. Total annual healthcare costs in 2005 were almost twice as high for former drivers compared with current drivers ($13,046 vs. $7,054; mean difference = $5,992; 95% CI: -$360, $12,344), although this relationship was not statistically significant (CR = 1.61; 95% CI: 0.88, 2.96).Impact on IndustryFormer drivers were more than three times as likely as current drivers to use mental health services, and tended to use more emergency and inpatient services. Further research on factors that potentially mediate the relationship between driving status and health service use is warranted.  相似文献   
864.
865.
This paper summarizes data from ten studies examining the relationship between organizational and workplace factors and injury rates. The studies were identified from a systematic literature search, as well as from other sources, and were included if they reported comparisons among at least 20 workplaces. Factors that were examined in at least two studies were identified. Their relationship with injury rates was determined. It was not possible to make quantitative comparisons between studies. We looked for ‘consistency’ or ‘contradiction’ in the relationships. Among the variables ‘consistency’ associated with lower injury rates were: empowerment of the workforce (in general matters); delegation of safety activities; and an active role (in health and safety) of top management. Among the ‘contradictory’ variables were the level and use of discipline for safety violations; and several others that were contradictory only in subgroups of the same study. We discuss the limitations of synthesizing results from the diverse studies.  相似文献   
866.
Various models of fireball diameter have been evaluated by statistical techniques. The model of Gayle for fireball diameter estimation showed good agreement between the predicted and experimental data. The models relating to fireball duration, transmissivity and view factor have been selected based on their relative merits. A user interactive computer program has been developed to predict thermal hazards from fireballs in chemical process industries.  相似文献   
867.
868.
869.
The workplace has become the locus of many stress management and stress reduction interventions. However, little attention has focused on how worksite factors affect the implementation and impact of such interventions. In this paper, we investigate the effect of new versus traditional industrial relations practices on the impact of a worksite stress reduction program in a manufacturing setting. More specifically, a participatory action research (PAR) stress project is described and evaluated in two different labor–management relations contexts. One organization is characterized by the emerging ’new‘ industrial relations system where labor–management relations incorporate elements of joint problem-solving. The other organization has a more traditional approach where labor–management relations are formally adversarial. Results indicate that the labor–management relations context did influence the impact of the stress project. Involvement in the PAR stress project enhanced employee participation in decision-making in both contexts. However, involvement in the stress project enhanced employees' perceptions of the climate for participation only in the organization with more cooperative industrial relations. Increases in coworker support and decreases in depressive symptoms were associated with involvement in the PAR stress project in the organization with more adversarial industrial relations.  相似文献   
870.
Physical therapists engage in work tasks that expose them to occupational risk factors related to musculoskeletal disorders. Due to the gap in the literature on instruments focused on those workers, this study adapted a job factors questionnaire to physical therapists, and assessed its psychometric properties. The questionnaire was adapted and its content validity was established. The psychometric properties were evaluated among 142 physical therapists. Reliability was verified using the temporal-stability design and internal consistency. Construct validity was assessed with the known-groups technique. Test-retest results demonstrated intraclass correlation coefficients between .82 and .90 (p < .001). Cronbach's α of .91 verified the reliability of the questionnaire. The known-groups technique demonstrated a statistically significant difference on the scores of the items when physical therapists were compared to office workers. The results indicated that the adapted questionnaire had acceptable psychometric properties for assessing problematic job factors among physical therapists working in hospitals.  相似文献   
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