167 resultados para Daunou, P. C. F. (Pierre Claude François), 1761-1840.


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This study examined the impact of perceived high-involvement work practices on job demands (role conflict, role overload and role ambiguity) and burnout (emotional exhaustion and depersonalisation). The study was conducted in a Canadian general hospital. Findings from structural equation modelling (N = 545) revealed that perceived HIWPs were significantly and negatively related to job demands and burnout. Role conflict and role overload have a significant positive association with emotional exhaustion and depersonalisation. Finally, role conflict and role overload partially mediate the relationship between perceived HIWPs and burnout. We discuss the theoretical and managerial implications of these findings for our understanding of how HIWPs influence the job demands and burnout of employees.

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This paper investigates the characteristics of the shadowed fading observed in off-body communications channels at 5.8 GHz. This is realized with the aid of the $\kappa-\mu$ / gamma composite fading model which assumes that the transmitted signal undergoes $\kappa-\mu$ fading which is subject to \emph{multiplicative} shadowing. Based on this, the total power of the multipath components, including both the dominant and scattered components, is subject to non-negligible variations that follow the gamma distribution. For this model, we present an integral form of the probability density function (PDF) as well as important analytic expressions for the PDF, cumulative distribution function, moments and moment generating function. In the case of indoor off-body communications, the corresponding measurements were carried out in the context of four explicit individual scenarios namely: line of sight (LOS) and non-LOS (NLOS) walking, rotational and random movements. The measurements were repeated within three different indoor environments and considered three different hypothetical body worn node locations. With the aid of these results, the parameters for the $\kappa-\mu$ / gamma composite fading model were estimated and analyzed extensively. Interestingly, for the majority of the indoor environments and movement scenarios, the parameter estimates suggested that dominant signal components existed even when the direct signal path was obscured by the test subject's body. Additionally, it is shown that the $\kappa-\mu$ / gamma composite fading model provides an adequate fit to the fading effects involved in off-body communications channels. Using the Kullback-Leibler divergence, we have also compared our results with another recently proposed shadowed fading model, namely the $\kappa-\mu$ / lognormal LOS shadowed fading model. It was found that the $\kappa-\mu$ / gamma composite fading model provided a better fit for the majority of the scenarios considered in this study.