14,479 research outputs found

    Mars: Seasonally variable radar reflectivity

    Get PDF
    The 1971/1973 Mars data set acquired by the Goldstone Solar System Radar was analyzed. It was established that the seasonal variations in radar reflectivity thought to occur in only one locality on the planet (the Solis Lacus radar anomaly) occur, in fact, over the entire subequatorial belt observed by the Goldstone radar. Since liquid water appears to be the most likely cause of the reflectivity excursions, a permanent, year-round presence of subsurface water (frozen or thawed) in the Martian tropics can be inferred

    Best practice fox management in Australia

    Get PDF
    Saunders, G., McLeod, L

    Negative oxygen vacancies in HfO2_2 as charge traps in high-k stacks

    Full text link
    We calculated the optical excitation and thermal ionization energies of oxygen vacancies in m-HfO2_2 using atomic basis sets, a non-local density functional and periodic supercell. The thermal ionization energies of negatively charged V^- and V2^{2-} centres are consistent with values obtained by the electrical measurements. The results suggest that negative oxygen vacancies are the likely candidates for intrinsic electron traps in the hafnum-based gate stack devices.Comment: 3 pages, 2 figure

    Operating experience with four 200 kW Mod-0A wind turbine generators

    Get PDF
    The windpowered generator, Mod-0A, and its advantages and disadvantages, particularly as it affects reliability, are discussed. The machine performance with regard to power availability and power output is discussed

    Two new topologically ordered glass phases of smectics confined in anisotropic random media

    Get PDF
    We show that smectic liquid crystals confined in_anisotropic_ porous structures such as e.g.,_strained_ aerogel or aerosil exhibit two new glassy phases. The strain both ensures the stability of these phases and determines their nature. One type of strain induces an ``XY Bragg glass'', while the other creates a novel, triaxially anisotropic ``m=1 Bragg glass''. The latter exhibits anomalous elasticity, characterized by exponents that we calculate to high precision. We predict the phase diagram for the system, and numerous other experimental observables.Comment: 4 RevTeX pgs, 2 eps figures, submitted to Phys. Rev. Let

    Indicators of Woman Abuse Based on a Chart Review at a Family Practice Center

    Full text link
    Objective: To identify demographic and health indicators of domestic violence. Design: Anonymous questionnaire survey of patients regarding violence and a chart review regarding symptoms and diagnoses. Setting: Community-based family practice residency training center in a midwestern city. Participants: Women 18 years of age or older visiting the center over a 2-month period in 1990. Of 476 eligible participants, 394 (82.7%) consented to complete the survey. Measures: A detailed, standardized measure of violence was used. Physical and psychological problems were given codes from the International Classification of Diseases, Ninth Revision (ICD-9). Results: Younger women and those separated or divorced from their partners were more likely to have been victims. Never-married women also had substantially high rates of victimization. Depression was the strongest indicator of victimization, even when controlling for demographic factors. Back pain, ulcers, headaches, and anxiety were not strong indicators of abuse. A classification analysis showed that a combination of all variables could predict lifetime injury only about half the time and violence in the past year only about 20% of the time. Conclusions: Since neither demographic nor health factors could accurately predict who had been victimized, all women need to be asked about abuse. Physicians should also keep in mind that divorced and unmarried women are often affected by abuse, either immediately or by its long term aftereffects.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/89971/1/Saunders-Hamberger-Hovey-1993-Indicators of woman abuse based on a chart review at a family practice center AFM-AMA.pd

    The IRAS 1-Jy Survey of Ultraluminous Infrared Galaxies: I. The sample and Luminosity Function

    Full text link
    A complete flux-limited sample of 118 ultraluminous infrared galaxies (ULIGs) has been identified from the IRAS Faint Source Catalog (FSC). The selection criteria were a 60 micron flux density greater than 1 Jy in a region of the sky delta > -40 deg, |b| > 30 deg. All sources were subsequently reprocessed using coadded IRAS maps in order to obtain the best available flux estimates in all four IRAS wavelength bands. The maximum observed infrared luminosity is L_ir = 10^{12.90} L_{sun}, and the maximum redshift is z = 0.268. The luminosity function for ULIGs over the decade luminosity range L_ir = 10^{12} - 10^{13} L_{sun} can be approximated by a power law Phi (L) ~= L^{-2.35} Mpc^{-3} mag^{-1}. In the local Universe z < 0.1, the space density of ULIGs appears to be comparable to or slightly larger than that of optically selected QSOs at comparable bolometric luminosities. A maximum likelihood test suggests strong evolution for our sample; assuming density evolution proportional to (1+z)^{alpha} we find alpha = 7.6+/-3.2. Examination of the two-point correlation function shows a barely significant level of clustering, xi (r) = 1.6 +/- 1.2, on size scales r ~= 22 h^{-1} Mpc.Comment: 18 pages of text, 10 pages of figures 1 to 6, 6 pages of tables 1 to 3, ApJS accepte
    corecore