The Changing Spatial Concentration of America’s Rural Poor Population

This paper documents changing patterns of concentrated poverty in nonmetro areas. Data from the 1970 through 2000 U.S. Census Summary Files reveal the changing shares of poor people and children living in rural counties with disproportionately poor populations. Nonmetro poverty rates – both overall and for children – declined more rapidly than metro rates in the 1990s. The 1990s also brought large reductions in the number of high-poverty nonmetro counties, and declines in the share of rural people, including rural poor people, who were living in them. In particular, the number and percentage of rural people living in extremely poor counties (i.e., over 40 percent) declined dramatically. This suggests a “drying up” of America’s rural pockets of poverty and indicates a decline in spatial inequality in nonmetro America, at least at the county level. On a less optimistic note, concentrated poverty among rural minorities remains exceptionally high (e.g., almost one-half of rural blacks live in poor counties). Moreover, the recent transformation of concentrated rural poverty may be short-lived. Rural children – especially rural minority children -- have poverty rates well above national and nonmetro rates, the concentration of rural minority children is often extreme (i.e., over 90 percent lived in high-poverty counties), and the number of nonmetro counties with high levels of persistent child poverty remains high. Rural children may be more disadvantaged than ever, if measured by their lack of exposure to middle-class role models, and their economic divergence with the rest of the nation’s children

The changing faces of America\u27s children and youth

The U.S. Census Bureau estimates indicate that between July 2008 and July 2009, 48.6 percent of the 4 million children born in the United States were minorities. In contrast, nearly 60 percent of the children born ten years ago were non-Hispanic white. This rapid change demonstrates that America\u27s youth are at the forefront of the country\u27s rapidly shifting demographic makeup. This brief reveals the factors causing this increase in the proportion of minority births

Population growth in new Hispanic destinations

Natural increase—more births than deaths—is now the major engine of Hispanic population growth in many large metro areas and their suburbs, as well as numerous smaller metropolitan areas and rural communities. Hispanics now account for half of U.S. population growth, and Hispanic population growth is the reason many communities grew instead of declined

The Changing Faces of America’s Children and Youth

Recent U.S. Census Bureau projections indicate that by the middle of this century, non-Hispanic whites will cease to be a majority of the American population. In this article we document how for America’s youngest residents, the future is already here. America’s rapidly changing racial and ethnic composition has important implications for intergroup relations, ethnic identities, and electoral politics

The Changing Spatial Concentration of America\u27s Rural Poor Population

This paper documents changing patterns of concentrated poverty in nonmetro areas. Data from the Decennial U.S. Census Summary Files show that poverty rates—both overall and for children—declined more rapidly in nonmetro than metro counties in the 1990s. The 1990s also brought large reductions in the number of high-poverty nonmetro counties and declines in the share of rural people, including rural poor people, who were living in them. This suggests that America\u27s rural pockets of poverty may be “drying up” and that spatial inequality in nonmetro America declined over the 1990s, at least at the county level. On a less optimistic note, concentrated poverty among rural minorities remains exceptionally high. Roughly one-half of all rural blacks and one-third of rural Hispanics live in poor counties. Poor minorities are even more highly concentrated in poor areas. Rural children—especially rural minority children—have poverty rates well above national and nonmetro rates, the concentration of rural minority children is often extreme (i.e., over 80% lived in high-poverty counties), and the number of nonmetro counties with high levels of persistent child poverty remains high (over 600 counties). Rural poor children may be more disadvantaged than ever, especially if measured by their lack of access to opportunities and divergence with children living elsewhere. Patterns of poverty among rural children—who often grow up to be poor adults— suggest that recent declines in concentrated rural poverty may be short-lived

Wave propagation in fiber composite laminates, part 2

An experimental investigation was conducted to determine the wave propagation characteristics, transient strains and residual properties in unidirectional and angle-ply boron/epoxy and graphite/epoxy laminates impacted with silicone rubber projectiles at velocities up to 250 MS-1. The predominant wave is flexural, propagating at different velocities in different directions. In general, measured wave velocities were higher than theoretically predicted values. The amplitude of the in-plane wave is less than ten percent of that of the flexural wave. Peak strains and strain rates in the transverse to the (outer) fiber direction are much higher than those in the direction of the fibers. The dynamics of impact were also studied with high speed photography

Lamination residual stresses in hybrid composites, part 1

An experimental investigation was conducted to study lamination residual stresses for various material and loading parameters. The effects of hybridization on residual stresses and residual properties after thermal cycling under load were determined in angle-ply graphite/Kevlar/epoxy and graphite/S-glass/epoxy laminates. Residual strains in the graphite plies are not appreciably affected by the type and number of hybridizing plies. Computed residual stresses at room temperature in the S-glass plies reach values up to seventy-five percent of the transverse strength of the material. Computed residual stresses in the graphite plies exceed the static strength by approximately ten percent. In the case of Kevlar plies, computed residual stresses far exceed the static strength indicating possible early failure of these plies. Static testing of the hybrids above indicates that failure is governed by the ultimate strain of the graphite plies. In thermally cycled hybrids, in general, residual moduli were somewhat lower and residual strengths were higher than initial values

Lamination residual stresses in fiber composites

An experimental investigation was conducted to determine the magnitude of lamination residual stresses in angle-ply composites and to evaluate their effects on composite structural integrity. The materials investigated were boron/epoxy, boron/polyimide, graphite/low modulus epoxy, graphite/high modulus epoxy, graphite/polyimide and s-glass/epoxy. These materials were fully characterized. Static properties of laminates were also determined. Experimental techniques using embedded strain gages were developed and used to measure residual strains during curing. The extent of relaxation of lamination residual stresses was investigated. It was concluded that the degree of such relaxation is low. The behavior of angle-ply laminates subjected to thermal cycling, tensile load cycling, and combined thermal cycling with tensile load was investigated. In most cases these cycling programs did not have any measurable influence on residual strength and stiffness of the laminates. In the tensile load cycling tests, the graphite/polyimide shows the highest endurance with 10 million cycle runouts at loads up to 90 percent of the static strength