NAVSTAR: Global positioning system an evolutionary research and development program

A description is given of NAVSTAR and the conception validation program for the system. System compatibility and performance projections are discussed

Tank Tests of Model 11-G Flying-boat Hull

The NACA model 11-G flying-boat hull, a modification of NACA model 11-A was tested over a range of loadings. The planing bottom of model 11-G has a variable-radius flare, or concavity, at the chines in contrast to the straight V planing bottom of model 11-A. The results are given as curves of resistance and trimming moment plotted against speed for various angles of trim. The characteristics of the form at the optimum angles of trim are given in non-dimensional form as curves of resistance coefficient, best trim angle, and trimming-moment coefficient plotted against speed coefficient. As compared with the original form, model 11-G is shown to have higher resistance at all loads and speeds and higher maximum trimming moments at heavy loads. The spray pattern, however, is generally more favorable, indicating that the service performance of model 11-A would be improved by some form of chime flare

Knowledge of Infant/Toddler Development Among Low-Income Families

Pretest data from a two-year project entitled An Early Intervention Program for Parents of Young Children at-Risk were collected and analyzed, in a sample of 2,191 low-income parents, for Head Start participation and baseline information. Respondents participating in the sample were from the states of California, Delaware, Nevada, South Carolina, and Utah. For their participation in the study, respondents received a free subscription to age-paced newsletters, which contained information about appropriate growth expectancies, nutrition, and guidance for their child of 36 months or younger. Newsletters were mailed monthly to parents who had children 12 months and younger and every other month to parents with children older than 12 months. Knowledge of infant/toddler development among Head Start and non-Head Start parents was measured by i-test comparisons. Univariate analysis of demographic influences on developmental knowledge was computed by a oneway ANOVA and Pearson correlation coefficients. Demographic variables measured were state of residence, race, educational level, marital status, employment status, attitude, income level, number of children, supplemental programs, and age of parent. Findings revealed that Head start parents did not have a significantly greater knowledge of infant/toddler development than non-Head start parents who had more than one child. Developmental knowledge scores were higher for Head start parents than non-Head start first-time parents. All participating Head start parents had at least two children, one in the Head start program and one other child 25 months or younger. There were differences in developmental knowledge scores by state of residence, race, educational level, marital status, and employment status. Demographic variables found to have a positive correlation with developmental knowledge scores were attitude, income level, number of children, and age of parents. There was a negative correlation with the effect of supplemental programs. Programs tested for this effect were AFDC, Food stamps, Medicaid, WIC, Social Security, and Head Start. A greater proportion of Head Start parents participated in these income-assistance programs, which may have influenced their scores for child development knowledge

Considering consumer choice in the economic evaluation of mandatory health programmes: A review

Objective: Governments are increasing their focus on mandatory public health programmes following positive economic evaluations of their impact. This review aims to examine whether loss of consumer choice should be included in economic evaluations of mandatory health programmes (MHP). Method: A systematic literature review was conducted to identify economic evaluations of MHP, whether they discuss the impact on consumer choice and any methodological limitations. Results: Overall 39 economic evaluations were identified, of which 10 discussed the loss of consumer choice and 6 attempted to place a value on the loss of consumer choice. Methodological limitations included: measuring the marginal cost of compliance, unavailability of price elasticity estimates, the impact of income effects, double counting health impacts, biased willingness-to-pay responses, and "protest" responses. Overall it was found that the inclusion of the loss of consumer choice rarely impacted on the final outcome of the study. Conclusion: The impact of MHP on the loss of consumer choice has largely been ignored in economic evaluations. Its importance remains uncertain due to its infrequent inclusion and significant methodological limitations. Further research regarding which methodology is best for valuing the loss of consumer choice and whether it is important to the final implementation decision is warranted. © 2010 Elsevier Ireland Ltd