A fault-tolerant multiprocessor architecture for aircraft, volume 1

A fault-tolerant multiprocessor architecture is reported. This architecture, together with a comprehensive information system architecture, has important potential for future aircraft applications. A preliminary definition and assessment of a suitable multiprocessor architecture for such applications is developed

Exploring psychosocial predictors of STI testing in University students

Peer reviewedPublisher PD

Bio-Security Proficiencies Project for Beginning Producers in 4-H

Improving bio-security practices among 4-H members who raise and show project animals is important. Bio-security measures can reduce the risk of disease spread and mitigate potential health and economic risks of disease outbreaks involving animal and zoonotic pathogens. Survey data provided statistical evidence that the Bio-Security Proficiencies Project for Beginning Producers in 4-H advanced youth participants\u27 knowledge and skills related to bio-security and financial risk management. Furthermore, the project provided youth with opportunities to apply their understanding and abilities to authentic settings and extend their learning to their communities

The Weak Clustering of Gas-Rich Galaxies

We examine the clustering properties of HI-selected galaxies through an analysis of the HI Parkes All-Sky Survey Catalogue (HICAT) two-point correlation function. Various sub-samples are extracted from this catalogue to study the overall clustering of HI-rich galaxies and its dependence on luminosity, HI gas mass and rotational velocity. These samples cover the entire southern sky Dec < 0 deg, containing up to 4,174 galaxies over the radial velocity range 300-12,700 km/s. A scale length of r_0 = 3.45 +/- 0.25 Mpc/h and slope of gamma = 1.47 +/- 0.08 is obtained for the HI-rich galaxy real-space correlation function, making gas-rich galaxies among the most weakly clustered objects known. HI-selected galaxies also exhibit weaker clustering than optically selected galaxies of comparable luminosities. Good agreement is found between our results and those of synthetic HI-rich galaxy catalogues generated from the Millennium Run CDM simulation. Bisecting HICAT using different parameter cuts, clustering is found to depend most strongly on rotational velocity and luminosity, while the dependency on HI mass is marginal. Splitting the sample around v_rot = 108 km/s, a scale length of r_0 = 2.86 +/- 0.46 Mpc/h is found for galaxies with low rotational velocities compared to r_0 = 3.96 +/- 0.33 Mpc/h for the high rotational velocity sample.Comment: Accepted for publication in the Astrophysical Journa

System data communication structures for active-control transport aircraft, volume 2

The application of communication structures to advanced transport aircraft are addressed. First, a set of avionic functional requirements is established, and a baseline set of avionics equipment is defined that will meet the requirements. Three alternative configurations for this equipment are then identified that represent the evolution toward more dispersed systems. Candidate communication structures are proposed for each system configuration, and these are compared using trade off analyses; these analyses emphasize reliability but also address complexity. Multiplex buses are recognized as the likely near term choice with mesh networks being desirable for advanced, highly dispersed systems

System data communication structures for active-control transport aircraft, volume 1

Candidate data communication techniques are identified, including dedicated links, local buses, broadcast buses, multiplex buses, and mesh networks. The design methodology for mesh networks is then discussed, including network topology and node architecture. Several concepts of power distribution are reviewed, including current limiting and mesh networks for power. The technology issues of packaging, transmission media, and lightning are addressed, and, finally, the analysis tools developed to aid in the communication design process are described. There are special tools to analyze the reliability and connectivity of networks and more general reliability analysis tools for all types of systems

Evidence for Fermi surface reconstruction in the static stripe phase of La1.8−x_{1.8-x}Eu0.2_{0.2}Srx_xCuO4_{4}, x=1/8x=1/8

We present a photoemission study of La$_{0.8-x}$Eu$_{0.2}$Sr$_x$CuO$_{4}$ with doping level $x$=1/8, where the charge carriers are expected to order forming static stripes. Though the local probes in direct space seem to be consistent with this idea, there has been little evidence found for such ordering in quasiparticle dispersions. We show that the Fermi surface topology of the 1/8 compound develops notable deviations from that observed for La$_{2- x}$Sr$_x$CuO$_{4}$ in a way consistent with the FS reconstruction expected for the scattering on the antiphase stripe order

Choosing more mathematics : happiness through work?

This paper examines how A-level students construct relationships between work and happiness in their accounts of choosing mathematics and further mathematics A-level. I develop a theoretical framework that positions work and happiness as opposed, managed and working on the self and use this to examine students' dual engagement with individual practices of the self and institutional practices of school mathematics. Interviews with students acknowledge four imperatives that they use as discursive resources to position themselves as successful/unsuccessful students: you have to work, you have to not work, you have to be happy, you have to work at being happy. Tensions in these positions lead students to rework their identities or drop further mathematics. I then identify the practices of mathematics teaching that students use to explain un/happiness in work, and show how dependable mathematics and working together are constructed as 'happy objects' for students, who develop strategies for claiming control over these shapers of happiness. © 2010 British Society for Research into Learning Mathematics

Eta Carinae -- Physics of the Inner Ejecta

Eta Carinae's inner ejecta are dominated observationally by the bright Weigelt blobs and their famously rich spectra of nebular emission and absorption lines. They are dense (n_e ~ 10^7 to 10^8 cm^-3), warm (T_e ~ 6000 to 7000 K) and slow moving (~40 km/s) condensations of mostly neutral (H^0) gas. Located within 1000 AU of the central star, they contain heavily CNO-processed material that was ejected from the star about a century ago. Outside the blobs, the inner ejecta include absorption-line clouds with similar conditions, plus emission-line gas that has generally lower densities and a wider range of speeds (reaching a few hundred km/s) compared to the blobs. The blobs appear to contain a negligible amount of dust and have a nearly dust-free view of the central source, but our view across the inner ejecta is severely affected by uncertain amounts of dust having a patchy distribution in the foreground. Emission lines from the inner ejecta are powered by photoionization and fluorescent processes. The variable nature of this emission, occurring in a 5.54 yr event cycle, requires specific changes to the incident flux that hold important clues to the nature of the central object.Comment: This is Chapter 5 in a book entitled: Eta Carinae and the Supernova Impostors, Kris Davidson and Roberta M. Humphreys, editors Springe

Compared to high and low cannabis use, moderate use is associated with fewer cognitive deficits in psychosis

AbstractLiterature on the relationship of cannabis use and cognition in schizophrenia provides the paradoxical view that cannabis use is sometimes linked with less severe impairment in neurocognition. This paper explored the possibility that this is a reflection of a dose related response between lifetime cannabis use and two forms of cognition, neurocognition and metacognition, in schizophrenia. It was hypothesized that three groups of patients could be differentiated, those with (1) little to no cannabis use with poor levels of cognition, (2) moderate cannabis use and relatively better levels of cognition and (3) high cannabis use with relatively poorer levels of cognition. Sixty-six adults with schizophrenia completed assessments of neurocognition, metacognition and months of lifetime cannabis use. Ak-means cluster analysis yielded three distinct groups based on these assessments. The clusters included: (1) low cannabis/poor cognition (n=34); (2) heavy cannabis/moderately impaired cognition (n=10); and (3) moderate cannabis/higher cognition (n=22). Consistent with our hypothesis, participants with high and moderate lifetime cannabis use had lesser impairment of neurocognition and metacognition compared to low lifetime cannabis use. Participants with moderate lifetime cannabis use also had lesser impairment of metacognition compared to low and heavy use. These findings suggest that a dose related relationship exists between cannabis use and cognition. Results could be due to an influence of pre-existing cognitive level on likelihood of lifetime cannabis use, or to an interaction between use and cognitive function