40,809 research outputs found
The NASA digital VGH program, early results
Data from airline digital flight data recorders provides relevant statistical data for estimating fatigue life consumption of the current airliner fleet and for design criteria updating for future designs. The data indicates real operating effects due to the autopilot, i.e., gust response frequency peak increase by 2 or 3 times, and the existence of the low frequency low amplitude limit cycle motion in altitude hold. The extension of more data types for ground operations is considered. Onboard processing of simple data types is also considered
How Much Care Do the Aged Receive from Their Children? A Bimodal Picture of Contact and Assistance
This paper presents some preliminary findings about contact between the aged and their children based on a new survey of the aged and their children, entitled The Hebrew Rehabilitation Center for the Aged-NBER (HRC-NBER) Child Survey. Data on extended families is quite limited. The HRC-NBER Child Survey represents one of the few attempts to collect economic and demographic data on the elderly and their children. While these data will be used in future,research to test structural models of the living arrangements, the purposes of the current paper are to describe the survey and to examine contact between the elderly and their children. While our findings are preliminary and will be updated and expanded as we receive more data, it appears that a significant minority of the elderly, many of whom need assistance with the activities of daily living, have either no children or have only limited contact with their children. Contact between children and the vulnerable elderly appears to be less than that between children and the nonvulnerable elderly, and the amount of contact between children and the institutionalized elderly seems the least of all. In addition, although many of the parents in our data are very poor, financial support from children to parents, other than in the form of shared housing, is uncommon. The impression given by these data is that many of the elderly are very well cared for by their children, while a significant minority either have no children or have no children who provide significant time or care. Some of the findings for this sample are striking: (1) over a fifth of the elderly have no children. (2) over one half of the elderly either do not have a daughter or do not have a daughter who lives within an hour of them. (3) over half of single elderly males and females and over two fifths of vulnerable single elderly males and females live completely alone. (4) of the elderly who have children, fewer than a quarter live with their children. (5) a small fraction of elderly with children hear from them at most on a yearly basis. (6) almost 10 percent of the children of the elderly have at most yearly contact. (7) financial assistance from children to the elderly, even in cases where the elderly are quite poor, is extremely rare. (8) in a typical month over a quarter of elderly who have children do not physically spend time with their children.
Development and Psychometric Properties of an Assessment for Persons With Intellectual Disability—The interRAI ID
This paper describes the development of the interRAI-Intellectual Disability (interRAI ID), a comprehensive instrument that assesses all key domains of interest to service providers relative to a person with an intellectual disability (ID). The authors report on the reliability and validity of embedded scales for cognition, self-care, aggression, and depression. Four provider agencies volunteered to participate and assessed a total of 160 community-dwelling adults with ID using the interRAI ID, Dementia Questionnaire for Persons with Mental Retardation, and Reiss Screen for Maladaptive Behavior. All scales had acceptable levels of internal consistency (Cronbach’s alpha 0.74–0.93) and good relationships with the criterion measures ( r  = 0.50–0.93, p  < 0.0001). The development of the interRAI ID represents an important and successful first step toward an integrated, comprehensive, and standardized assessment of adults with ID. Use of this instrument may lead to more appropriate support planning, enhanced communication between various professionals supporting persons with ID, and a more seamless approach to supports across the health and social service systems.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75618/1/j.1741-1130.2006.00094.x.pd
Flexible conformable hydrophobized surfaces for turbulent flow drag reduction
In recent years extensive work has been focused onto using superhydrophobic surfaces for drag reduction applications. Superhydrophobic surfaces retain a gas layer, called a plastron, when submerged underwater in the Cassie-Baxter state with water in contact with the tops of surface roughness features. In this state the plastron allows slip to occur across the surface which results in a drag reduction. In this work we report flexible and relatively large area superhydrophobic surfaces produced using two different methods: Large roughness features were created by electrodeposition on copper meshes; Small roughness features were created by embedding carbon nanoparticles (soot) into Polydimethylsiloxane (PDMS). Both samples were made into cylinders with a diameter under 12 mm. To characterize the samples, scanning electron microscope (SEM) images and confocal microscope images were taken. The confocal microscope images were taken with each sample submerged in water to show the extent of the plastron. The hydrophobized electrodeposited copper mesh cylinders showed drag reductions of up to 32% when comparing the superhydrophobic state with a wetted out state. The soot covered cylinders achieved a 30% drag reduction when comparing the superhydrophobic state to a plain cylinder. These results were obtained for turbulent flows with Reynolds numbers 10,000 to 32,500
Growth to early adulthood following extremely preterm birth: the EPICure study.
OBJECTIVE: To investigate growth trajectories from age 2.5 to 19 years in individuals born before 26 weeks of gestation (extremely preterm; EP) compared with term-born controls. METHODS: Multilevel modelling of growth data from the EPICure study, a prospective 1995 birth cohort of 315 EP participants born in the UK and Ireland and 160 term-born controls recruited at school age. Height, weight, head circumference and body mass index (BMI) z-scores were derived from UK standards at ages 2.5, 6, 11 and 19 years. RESULTS: 129 (42%) EP children were assessed at 19 years. EP individuals were on average 4.0 cm shorter and 6.8 kg lighter with a 1.5 cm smaller head circumference relative to controls at 19 years. Relative to controls, EP participants grew faster in weight by 0.06 SD per year (95% CI 0.05 to 0.07), in head circumference by 0.04 SD (95% CI 0.03 to 0.05), but with no catch-up in height. For the EP group, because of weight catch-up between 6 and 19 years, BMI was significantly elevated at 19 years to +0.32 SD; 23.4% had BMI >25 kg/m2 and 6.3% >30 kg/m2 but these proportions were similar to those in control subjects. EP and control participants showed similar pubertal development in early adolescence, which was not associated with height at 19 years in either study group. Growth through childhood was related to birth characteristics and to neonatal feeding practices. CONCLUSIONS: EP participants remained shorter and lighter and had smaller head circumferences than reference data or controls in adulthood but had elevated BMI
Renormalization of composite operators
The blocked composite operators are defined in the one-component Euclidean
scalar field theory, and shown to generate a linear transformation of the
operators, the operator mixing. This transformation allows us to introduce the
parallel transport of the operators along the RG trajectory. The connection on
this one-dimensional manifold governs the scale evolution of the operator
mixing. It is shown that the solution of the eigenvalue problem of the
connection gives the various scaling regimes and the relevant operators there.
The relation to perturbative renormalization is also discussed in the framework
of the theory in dimension .Comment: 24 pages, revtex (accepted by Phys. Rev. D), changes in introduction
and summar
Scramjet sidewall burning: Preliminary shock tunnel results
Experiments performed with a two dimensional model scramjet with particular emphasis on the effect of fuel injection from a wall are reported. Air low with a nominal Mach number of 3.5 and varied enthalpies was produced. It was found that neither hydrogen injection angle nor combustor divergence angle had any appreciable effect on thrust values while increased combustor length appeared to increase thrust levels. Specific impulse was observed to peak when hydrogen was injected at an equivalence ratio of about 2. Lowering the Mach number of the injected hydrogen at low equivalence ratios, less than 4, appeared to benefit specific impulse while hydrogen Mach number had little effect at higher equivalence ratios. When a 1:1 mixture by volume of nitrogen and oxygen is used instead of air as a test gas, it is found that hydrogen combustion is enhanced but only at high enthalpies
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An Apparent Relation between ELM Occurrence Times and the Prior Evolution of Divertor Flux Loop Measurements in JET
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