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The relationship between alcohol consumption patterns and car, work, sports and home accidents for different age groups 总被引:5,自引:0,他引:5
The purpose of this study was to examine the relationship between alcohol consumption patterns and car, work, sports and home accidents for different age groups. A secondary analysis of data from a randomized household survey of 10385 Canadians was conducted. Overall, alcohol consumption patterns were significantly associated with car collisions, work and sports accidents for younger age groups (i.e. 15-24 and 25-34), but this relationship was not significant for the older age groups. 相似文献
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Nomination sampling is a sampling process in which every observation is the maximum of a random sample from some distribution. If all samples are taken from a single underlying CDF, F , data can be viewed as consisting of pairs (X i,K i) where K i is the size of sample i and, given K i=k i, X i is distributed according to CDF F ki. R.A. Boyles and F.J. Samaniego (1986) developed a nonparametric maximum-likelihood estimator of F . In the present work, their approach is extended to obtain estimates of the quantiles of F and to study the limit theory and consistency properties of these estimates. These results generalize the results of T.R. Willemain (1980), who discussed the estimation of the median of F based on nomination samples 相似文献
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In this study the desizing, scouring, bleaching and slack mercerising of cotton fabric by a one–step process at different sodium hydroxide concentrations, impregnation temperatures and curing times were examined. The results indicate that when the fabrics are mercerised at lower temperature, the strength retention and colour strength are enhanced. When the sodium hydroxide concentration is increased, these properties also increase. When cotton fabrics are mercerised for 3 min at 40C and cured for 30 s at 120C, their physical properties are similar to those obtained using a conventional two–step approach. 相似文献
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G. N. Wells L. J. Sluys R. de Borst 《International journal for numerical methods in engineering》2002,53(5):1235-1256
A numerical model is developed which allows the inclusion of displacement discontinuities in a strain‐softening medium, independent of the finite element mesh structure. Inelastic deformations develop in the continuum and, when a critical threshold of inelastic deformation is reached, a displacement discontinuity is inserted. Discontinuities are introduced using the partition of unity concept which allows discontinuous functions to be added to the standard finite element basis. It is shown that the introduction of displacement discontinuities at the later stages of the failure process can lead to a failure mode that is fundamentally different than that using a continuum model only. This combined continuum‐discontinuous model is better able to describe the entire failure process than a continuum or a discrete model alone and treats mode‐I and mode‐II failure in a unified fashion. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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