14,813 research outputs found
Child support enforcement for teenage fathers: Problems and prospects
The NLSY data indicate that about 7.3 percent of teenage males become fathers and that very few of these fathers live with their children. Father absence and the concurrent increase in female-headed households are closely associated with the impoverishment of children. Most absent teen fathers never come into contact with the child support enforcement program, and the extent to which they financially support their children informally is not well understood. While the income of absent teen fathers is low in the teen years, it increases over time, as does the potential for collecting child support. Nevertheless, men who were absent teen fathers earn less in early adulthood than men who deferred parenting until age twenty or later and teen fathers who lived with their children. Early establishment of paternity and greater standardization in the treatment of adolescent fathers by the child support enforcement program are recommended. Further, the substantial and persistent income deficit experienced by adolescent fathers who live apart from their children raises an interesting dilemma. While children may benefit financially and psychosocially from living with two parents, the lower income of men who were absent teenage fathers may make them poor marital prospects. This raises doubts about the recent recommendations of some scholars that we should bring back the shotgun wedding.
Aperture synthesis for microwave radiometers in space
A technique is described for obtaining passive microwave measurements from space with high spatial resolution for remote sensing applications. The technique involves measuring the product of the signal from pairs of antennas at many different antenna spacings, thereby mapping the correlation function of antenna voltage. The intensity of radiation at the source can be obtained from the Fourier transform of this correlation function. Theory is presented to show how the technique can be applied to large extended sources such as the Earth when observed from space. Details are presented for a system with uniformly spaced measurements
Sensitivity of a climatologically-driven sea ice model to the ocean heat flux
Ocean heat flux sensitivity was studied on a numerical model of sea ice covering the Weddell Sea region of the southern ocean. The model is driven by mean monthly climatological atmospheric variables. For each model run, the ocean heat flux is uniform in both space and time. Ocean heat fluxes below 20 W m to the minus 2 power do not provide sufficient energy to allow the ice to melt to its summertime thicknesses and concentrations by the end of the 14 month simulation, whereas ocean heat fluxes of 30 W m to the minus 2 power and above result in too much ice melt, producing the almost total disappearance of ice in the Weddell Sea by the end of the 14 months. These results are dependent on the atmospheric forcing fields
Bridging the gap between social tagging and semantic annotation: E.D. the Entity Describer
Semantic annotation enables the development of efficient computational methods for analyzing and interacting with information, thus maximizing its value. With the already substantial and constantly expanding data generation capacity of the life sciences as well as the concomitant increase in the knowledge distributed in scientific articles, new ways to produce semantic annotations of this information are crucial. While automated techniques certainly facilitate the process, manual annotation remains the gold standard in most domains. In this manuscript, we describe a prototype mass-collaborative semantic annotation system that, by distributing the annotation workload across the broad community of biomedical researchers, may help to produce the volume of meaningful annotations needed by modern biomedical science. We present E.D., the Entity Describer, a mashup of the Connotea social tagging system, an index of semantic web-accessible controlled vocabularies, and a new public RDF database for storing social semantic annotations
Another factor to consider in choosing a child support guideline: Errors in child support calculations
In an effort to standardize the calculation of monthly child support awards, the federal government requires states to use preestablished formulas to determine the amount of awards. However, because of human error, differences in the experience and training of the officials making the calculations, and the extent to which computers are used to calculate the awards, the formulas do not always yield the same result. In fact, the discrepancy between the amount calculated by an individual child support official and the approved amount as calculated by the state in which that official works can be quite large, on the order of several hundred dollars. Adopting simpler formulas will reduce errors; this should be a priority even if child support officials use computers to calculate award amounts (computers can reduce errors but will not eliminate them, particularly in the case of complex formulas). Efforts to further the training and education of personnel who calculate awards would also help, and child support offices should revise their formulas to cover high-income cases.
Ion Beams in Multi-Species Plasma
Argon and xenon ion velocity distribution functions are measured in Ar-He, Ar-Xe, and Xe-He expanding helicon plasmas to determine if ion beam velocity is enhanced by the presence of lighter ions. Contrary to observations in mixed gas sheath experiments, we find that adding a lighter ion does not increase the ion beam speed. The predominant effect is a reduction of ion beam velocity consistent with increased drag arising from increased gas pressure under all conditions: constant total gas pressure, equal plasma densities of different ions, and very different plasma densities of different ions. These results suggest that the physics responsible for the acceleration of multiple ion species in simple sheaths is not responsible for the ion acceleration observed in expanding helicon plasmas
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