Techniques for improving reliability of computers

Modular design techniques improve methods of error detection, diagnosis, and recovery. Theoretical computer (MARCS (Modular Architecture for Reliable Computer Systems)) study deals with postulated and modeled technology indigenous to 1975-1980. Study developments are discussed

Dyke architecture, mineral layering, and magmatic convection; new perspectives from the Younger Giant Dyke Complex, S Greenland

The expedition was funded by the Mining Institute of Scotland Trust, the Institute of Materials, Minerals and Mining, the Society of Economic Geologists Hickok-Radford Fund, the Edinburgh Geological Society, the Augustine Courtauld trust and the Scott Polar Research Institute.Igneous sheet intrusions are a fundamental component of volcano plumbing systems. Identifying how sheet intrusion emplacement and geometry controls later magmatic processes is critical to understanding the distribution of volcanic eruptions and magma-related ore deposits. Using the Younger Giant Dyke Complex, a Mesoproterozoic suite of large (< 800 m wide) mafic dykes in southern Greenland, we assess the influence sheet of emplacement and geometry on subsequent magma flow and mush evolution. Through structural mapping, petrographic observations, and anisotropy of magnetic susceptibility fabric analyses, we show that the Younger Giant Dyke Complex was emplaced as a series of individual dyke segments, which following coalescence into a sheet intrusion remained largely isolated during their magmatic evolution. Through petrographic evidence for liquid-rich growth of cumulus phases, concentric magnetic fabrics, and the detailed study layered zones within the Younger Giant Dyke Complex, we infer magma convection occurred within the cores of each dyke element. We particularly relate layering to hydrodynamic sorting processes at a magma-mush boundary towards the base of each convection cell. Overall, our work demonstrates that the initial geometry of sheet intrusions can constrain magma flow patterns and affect the distribution of crystallisation regimes.Publisher PDFPeer reviewe

Buoyancy waves in Pluto's high atmosphere: Implications for stellar occultations

We apply scintillation theory to stellar signal fluctuations in the high-resolution, high signal/noise, dual-wavelength data from the MMT observation of the 2007 March 18 occultation of P445.3 by Pluto. A well-defined high wavenumber cutoff in the fluctuations is consistent with viscous-thermal dissipation of buoyancy waves (internal gravity waves) in Pluto's high atmosphere, and provides strong evidence that the underlying density fluctuations are governed by the gravity-wave dispersion relation.Comment: Accepted 18 June 2009 for publication in Icaru

Processing plant location studies II: Policy alternatives for New Zealand wool selling centres

The nature of the general facility location problem has been discussed previously by McCarthy, Rodgers & Higham and a method of solution outlined. The present paper aims to extend the solution technique so that a number of low cost solutions with differing spatial characteristics are generated. This permits entrepreneurs or policy makers to choose among the alternatives. The facility location problem can be stated as the determination of the number, size and location of a certain type of facility in order to satisfy the demand for the services provided; the "goodness" of any solution, relative to others, is measured in terms of some effectiveness criterion. For example one problem reported extensively in the agricultural economics literature is the determination of the number, size and location of agricultural commodity processing plants (freezing works, wool selling centres, grain storage depots), so that the sum of total transport (assembly plus distribution) costs and total processing costs are minimised. Another general type of problem receiving attention in applied operations research relates to the number, size and location of public emergency services (for example ambulance and hospital services). Here, some measure of cost effectiveness is optimised Empirical studies include those of Fitzsimmons, Savas and Volz. This paper is concerned primarily with processing and has two major sections. The first section outlines methodology and discusses Monte Carlo and "forcing" extensions of standard solutions. The second section applies such procedures to the New Zealand wool selling centres' location problem

An Eccentric Hot Jupiter Orbiting the Subgiant HD 185269

We report the detection of a Jupiter-mass planet in a 6.838 day orbit around the 1.28 solar mass subgiant HD 185269. The eccentricity of HD 185269b (e = 0.30) is unusually large compared to other planets within 0.1 AU of their stars. Photometric observations demonstrate that the star is constant to +/-0.0001 mag on the radial velocity period, strengthening our interpretation of a planetary companion. This planet was detected as part of our radial velocity survey of evolved stars located on the subgiant branch of the H-R diagram--also known as the Hertzsprung Gap. These stars, which have masses between 1.2 and 2.5 solar masses, play an important role in the investigation of the frequency of extrasolar planets as a function of stellar mass.Comment: 18 pages, 4 figures, 3 tables, ApJ in press (scheduled for Dec 2006, v652n2

Emerging Areas of Science: Recommendations for Nursing Science Education from the Council for the Advancement of Nursing Science Idea Festival

The Council for the Advancement of Nursing Science aims to “facilitate and recognize life-long nursing science career development” as an important part of its mission. In light of fast-paced advances in science and technology that are inspiring new questions and methods of investigation in the health sciences, the Council for the Advancement of Nursing Science convened the Idea Festival for Nursing Science Education and appointed the Idea Festival Advisory Committee (IFAC) to stimulate dialogue about linking PhD education with a renewed vision for preparation of the next generation of nursing scientists. Building on the 2005 National Research Council report Advancing The Nation\u27s Health Needs and the 2010 American Association of Colleges of Nursing Position Statement on the Research-Focused Doctorate Pathways to Excellence, the IFAC specifically addressed the capacity of PhD programs to prepare nursing scientists to conduct cutting-edge research in the following key emerging and priority areas of health sciences research: omics and the microbiome; health behavior, behavior change, and biobehavioral science; patient-reported outcomes; big data, e-science, and informatics; quantitative sciences; translation science; and health economics. The purpose of this article is to (a) describe IFAC activities, (b) summarize 2014 discussions hosted as part of the Idea Festival, and (c) present IFAC recommendations for incorporating these emerging areas of science and technology into research-focused doctoral programs committed to preparing graduates for lifelong, competitive careers in nursing science. The recommendations address clearer articulation of program focus areas; inclusion of foundational knowledge in emerging areas of science in core courses on nursing science and research methods; faculty composition; prerequisite student knowledge and skills; and in-depth, interdisciplinary training in supporting area of science content and methods

The Serendipitous Discovery of a Group or Cluster of young Galaxies at z=2.40 in Deep Hubble Space Telescope WFPC2 Images

We report the serendipitous discovery of a group or cluster of young galaxies at $z\simeq$2.40 in a 24-orbit HST/WFPC2 exposure of the field around the weak radio galaxy 53W002. Potential cluster members were identified on ground-based narrow-band redshifted Ly$\alpha$ images and confirmed via spectroscopy. In addition to the known weak radio galaxy 53W002 at z=2.390, two other objects were found to have excess narrow-band Ly$\alpha$ emission at $z\simeq$2.40. Both have been spectroscopically confirmed, and one clearly contains a weak AGN. They are located within one arcminute of 53W002, or $\sim0.23h_{100}^{-1}$Mpc ($q_o$=0.5) at $z\simeq$2.40, which is the physical scale of a group or small cluster of galaxies. Profile fitting of the WFPC2 images shows that the objects are very compact, with scale lengths $\simeq$0\farcs 1 ($\simeq0.39h_{100}^{-1}$kpc), and are rather faint (luminosities < L*), implying that they may be sub-galactic sized objects. We discuss these results in the context of galaxy and cluster evolution and the role that weak AGN may play in the formation of young galaxies.Comment: Accepted for publication in The Astrophysical Journal (Letters). 13 pages of gzip compressed and uuencoded PS. Figures are available at http://www.phys.unsw.edu.au/~spd/bib.htm

Sex and the Cinema: What American Pie Teaches the Young

This paper focuses upon the wildly successful blockbuster American Pie teenpics, especially American Pie 3 – the Wedding. I argue that these films, which are sited so securely within the visual and pedagogical machinery of Hollywood culture, are specifically designed to appeal to teenage male audiences, and to provide lessons in sex and romance. Movies like this are especially important as they are experienced by far more teenagers than, for example, instructional films or other classroom materials; indeed, as Henry Giroux has observed, "teens and youth learn how to define themselves outside of the traditional sites of instruction, such as the home and the school… Learning in the postmodern age is located elsewhere – in popular spheres that shape their identities, through forms of knowledge and desires that appear absent from what is taught in schools" (Giroux, 1997, p.49). In this paper I discuss whether the American Pie series is actually a "new age" effort which, via insubordinate performances of gender, contests the hegemonic field of signification which regulates the production of sex, gender and desire, or whether it is more accurately described as a retrogressive hetero-conservative opus with a veneer of sexual radicalism. In short, I intend to probe whether this filmic vector for sex education is all about the shaping of responsible, caring, vulnerable men, or is it guiding them to become just like their heterosexual, middle-class fathers? And whether, despite its riotous and raunchy advertising, American Pie really dishes up something spicy or something terribly wholesome instead

High eccentricity planets from the Anglo-Australian Planet Search

We report Doppler measurements of the stars HD187085 and HD20782 which indicate two high eccentricity low-mass companions to the stars. We find HD187085 has a Jupiter-mass companion with a ~1000d orbit. Our formal `best fit' solution suggests an eccentricity of 0.47, however, it does not sample the periastron passage of the companion and we find that orbital solutions with eccentricities between 0.1 and 0.8 give only slightly poorer fits (based on RMS and chi^2) and are thus plausible. Observations made during periastron passage in 2007 June should allow for the reliable determination of the orbital eccentricity for the companion to HD187085. Our dataset for HD20782 does sample periastron and so the orbit for its companion can be more reliably determined. We find the companion to HD20782 has M sin i=1.77+/-0.22M_JUP, an orbital period of 595.86+/-0.03d and an orbit with an eccentricity of 0.92+/-0.03. The detection of such high-eccentricity (and relatively low velocity amplitude) exoplanets appears to be facilitated by the long-term precision of the Anglo-Australian Planet Search. Looking at exoplanet detections as a whole, we find that those with higher eccentricity seem to have relatively higher velocity amplitudes indicating higher mass planets and/or an observational bias against the detection of high eccentricity systems.Comment: to appear in MNRA

Trend in ice moistening the stratosphere – constraints from isotope data of water and methane

Water plays a major role in the chemistry and radiative budget of the stratosphere. Air enters the stratosphere predominantly in the tropics, where the very low temperatures around the tropopause constrain water vapour mixing ratios to a few parts per million. Observations of stratospheric water vapour show a large positive long-term trend, which can not be explained by change in tropopause temperatures. Trends in the partitioning between vapour and ice of water entering the stratosphere have been suggested to resolve this conundrum. We present measurements of stratospheric H_(2)O, HDO, CH_4 and CH_(3)D in the period 1991–2007 to evaluate this hypothesis. Because of fractionation processes during phase changes, the hydrogen isotopic composition of H_(2)O is a sensitive indicator of changes in the partitioning of vapour and ice. We find that the seasonal variations of H_(2)O are mirrored in the variation of the ratio of HDO to H_(2)O with a slope of the correlation consistent with water entering the stratosphere mainly as vapour. The variability in the fractionation over the entire observation period is well explained by variations in H_(2)O. The isotopic data allow concluding that the trend in ice arising from particulate water is no more than (0.01±0.13) ppmv/decade in the observation period. Our observations suggest that between 1991 and 2007 the contribution from changes in particulate water transported through the tropopause plays only a minor role in altering in the amount of water entering the stratosphere