Basic avionics module design for general aviation aircraft

The design of an advanced digital avionics system (basic avionics module) for general aviation aircraft operated with a single pilot under IFR conditions is described. The microprocessor based system provided all avionic functions, including flight management, navigation, and lateral flight control. The mode selection was interactive with the pilot. The system used a navigation map data base to provide operation in the current and planned air traffic control environment. The system design included software design listings for some of the required modules. The distributed microcomputer uses the IEEE 488 bus for interconnecting the microcomputer and sensors

The effects of inflation on growth and fluctuations in dynamic macroeconomic models

Economic Growth;Macroeconomic Models;Inflation;Monetary Models

Continued evaluation of potential for geologic storage of carbon dioxide in the southeastern United States

Southern States Energy Board Duke Energy Santee Cooper Power Southern CompanyBureau of Economic Geolog

Hubble Space Telescope Ultraviolet Imaging and High-Resolution Spectroscopy of Water Photodissociation Products in Comet Hyakutake (C/1996 B2)

Comet Hyakutake (C/1996 B2) provided a target of opportunity for performing a systematic study of water photodissociation products in which we obtained data from three instruments on the Hubble Space Telescope (HST). The HST Goddard High Resolution Spectrograph (GHRS) was used to measure the line profile of hydrogen Lyα (H Lyα) at six locations around the coma of the comet, ranging from the nucleus to a displacement of 100,000 km, and covering different directions compared with the comet-sun line. GHRS yielded line profiles with a spectral resolution (FWHM ~4 km s^(-1)) that was a factor of 2-3 better than any previous H Lyα or Hα ground-based measurements. The Wide Field Planetary Camera 2 (WFPC2) and the Woods filter were used to obtain H Lyα images of the inner coma. The faint object spectrograph (FOS) was used to determine the OH production rate and monitor its variation throughout the HST observing sequence. The GHRS H Lyα line profiles show the behavior of a line profile that is optically thick in the core for positions near the nucleus (<5000 km) and gradually becoming more optically thin at larger displacements and lower column abundances. A composite H Lyα image constructed from four separate WFPC2 exposures is consistent with the relative fluxes seen in GHRS observations and clearly shows the dayside enhancement of a solar illuminated optically thick coma. These data were analyzed self-consistently to test our understanding of the detailed physics and chemistry of the expanding coma and our ability to obtain accurate water production rates from remote observations of gaseous hydrogen (H) and hydroxyl (OH), the major water dissociation products. Our hybrid kinetic/hydrodynamic model of the coma combined with a spherical radiative transfer calculation is able to account for (1) the velocity distribution of H atoms, (2) the spatial distribution of the H Lyα emission in the inner coma, and (3) the absolute intensities of H and OH emissions, giving a water production rate of (2.6 ± 0.4) × 10^(29) s^(-1) on 1996 April 4

On the role of the corpus callosum in interhemispheric functional connectivity in humans

Resting state functional connectivity is defined in terms of temporal correlations between physiologic signals, most commonly studied using functional magnetic resonance imaging. Major features of functional connectivity correspond to structural (axonal) connectivity. However, this relation is not one-to-one. Interhemispheric functional connectivity in relation to the corpus callosum presents a case in point. Specifically, several reports have documented nearly intact interhemispheric functional connectivity in individuals in whom the corpus callosum (the major commissure between the hemispheres) never develops. To investigate this question, we assessed functional connectivity before and after surgical section of the corpus callosum in 22 patients with medically refractory epilepsy. Section of the corpus callosum markedly reduced interhemispheric functional connectivity. This effect was more profound in multimodal associative areas in the frontal and parietal lobe than primary regions of sensorimotor and visual function. Moreover, no evidence of recovery was observed in a limited sample in which multiyear, longitudinal follow-up was obtained. Comparison of partial vs. complete callosotomy revealed several effects implying the existence of polysynaptic functional connectivity between remote brain regions. Thus, our results demonstrate that callosal as well as extracallosal anatomical connections play a role in the maintenance of interhemispheric functional connectivity

The self-assessed literacy index: Reliability and validity

Literacy is associated with many outcomes of research interest as well as with respondents’ ability to even participate in surveys, yet very few surveys attempt to measure it because doing so is often complex, requiring extensive tests. The central goal of this paper is to develop a parsimonious measure of respondents’ reading ability that does not require a complex literacy test. We use data from the 2003 National Assessment of Adult Literacy to identify correlates of reading ability to form a literacy index. These correlates include self-assessments of one’s ability to understand, read and write English, and literacy practices at home. Our literacy index reliably discerns literacy test scores above educational attainment, and the index shows high internal consistency (coefficient alpha = 0.78) and validity. The paper concludes with implications of these findings for survey research practitioners and suggestions for future research

The self-assessed literacy index: Reliability and validity

Literacy is associated with many outcomes of research interest as well as with respondents’ ability to even participate in surveys, yet very few surveys attempt to measure it because doing so is often complex, requiring extensive tests. The central goal of this paper is to develop a parsimonious measure of respondents’ reading ability that does not require a complex literacy test. We use data from the 2003 National Assessment of Adult Literacy to identify correlates of reading ability to form a literacy index. These correlates include self-assessments of one’s ability to understand, read and write English, and literacy practices at home. Our literacy index reliably discerns literacy test scores above educational attainment, and the index shows high internal consistency (coefficient alpha = 0.78) and validity. The paper concludes with implications of these findings for survey research practitioners and suggestions for future research