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991.
Adults and teenagers were surveyed to determine their use and ownership of 32 consumer, business, and entertainment technology devices. Demographics, technology experience, and “technophobia” were examined as potential discriminators between Confident Users, Hesitant Users, and Nonusers of each technological device. Results indicated that older, technophobic adults with little computer training and lower income, black and Hispanic, technophobic teenagers did not use most technological devices. 相似文献
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The effects of consumer education and information treatments on choice of alternative products are described. Knowledge of upholstery serviceability and flammability before and after these treatments is measured as well as simulated purchase behavior of 448 Canadian consumers. Subjects show an increase in knowledge between pre- and posttests. The choice of fire resistant upholstery differs among consumer information treatments but not among education treatments. The policy implications of these findings are discussed. 相似文献
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A logistic regression analysis is used to assess the impact of the wife's income, wage rate, and hours worked on changing from rental tenure to home ownership among a subsample of husband-wife house-holds from the Panel Study of Income Dynamics. Age of the wife, education of the wife, family size, and residence in the Northeast are significant predictors of change in tenure status between 1979 and 1983; of the wife's employment variables tested, only the number of hours worked (a proxy for labor force commitment) is a significant predictor of the probability of changing from rental tenure to home ownership. 相似文献
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The present study supplements Canadian consumer expenditure survey data with unique time use data to analyze family life cycle decisions regarding allocation of full income to market purchased consumption goods, home production, and leisure time. Results confirm that young children's presence causes families to increase their shares of full income allocated to home production and to decrease the shares of full income allocated to leisure. As a share of full income, expenditures for market goods steadily increase while expenditures for women's home production diminish as children age. 相似文献
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Charles M. Sheppard 《Process Safety Progress》1992,11(4):229-237
The behavior of an open system is modeled. Thus, for special cases, the void fraction is predicted as a function of location and time. The open system may be an open vessel or a vessel with an open relief device. A single governing equation is derived based on combining the material and energy balances with the churn-turbulent drift flux relationship and assuming no radial gradients. This partial differential equation is not solved. It is, however, bounded by homogeneous and all vapor venting. These special cases are solved. In homogeneous venting the key variable is time. In all vapor venting under pseudo-steady-state conditions the key variable is location. The solution of the partial differential equation is also discussed. Under pseudo-steady-state and churn-turbulent conditions, the open system is modeled. The minimum void fractions (corresponding to a maximum liquid inventory) with all vapor venting, for vertical, horizontal, and spherical vessels are predicted and compared. Analytical expressions for the local and average void fractions in a vertical vessel and non-unity distribution parameters are presented. Void fraction profiles are compared for three cases: 1. vertical cylinders with distribution parameters (Co values) of unity and 1.5, 2. horizontal and vertical cylinders with varying L/D ratios, and 3. spheres with inscribed vertical cylinders having constant gas production to bubble rise ratio (Ψ′ value). The vertical cylinder average void fraction for non-unity distribution parameters can now be calculated analytically. The horizontal cylinder average void fraction predicted by turning it upright results in an over prediction of at most 4%. The sphere average void fraction predicted via an inscribed vertical cylinder, with the same Ψ′ value, is consistenly high by at most 8%. 相似文献