24,166 research outputs found

    Claim your space: re-placing spaces to better meet the needs of the net generation

    Get PDF
    The challenge for the Reid Library at The University of Western Australia was the transformation of a 1960s building into a welcoming space with services and facilities appropriate for a more technologically demanding generation. A key issue was how to balance the continuing need for access to physical collections with the rapidly expanding demand for new kinds of learning spaces and facilities oriented towards on-line and collaborative learning and research. This paper outlines the approach taken to identify client needs (both physical and virtual), define and propose new service models, and transform learning spaces while maintaining access to physical collections

    Solar cell radiation response near the interface of different atomic number materials

    Get PDF
    The response of cobalt 60 irradiated N/P silicon solar cells was measured as a function of the atomic number of the medium adjacent to the cell and the direction of the gamma ray beam. The interpositioning of various thicknesses of aluminum between the adjacent material and the cell had the effect of moving the cell to various locations in an approximate monatomic numbered medium. Using this technique the solar cell response was determined at various distances from the interface for gold and beryllium. The results were compared with predictions based upon ionization chamber measurements of dose perturbations in aluminum and found to agree within five percent. Ionization chamber data was then used to estimate the influence of various base contact materials

    From Women’s Rights Lawyer in Pakistan to a Precarious Life in Australia: Learning From Lived Experience

    Get PDF
    Internationally the number of people displaced is at an historical high. The United Nations High Commissioner for Refugees (UNHCR) estimated that there were more than 79.5 million people displaced by conflict or persecution at the end of 2019 (UNHCR 2019). Australia is one of a relatively small number of countries that annually resettles refugees from overseas. In accordance with its international obligations under the UN Convention Relating to the Status of Refugees, Australia also provides protection to people who arrive in Australia seeking asylum. Historically, however, Australia’s policy response to people seeking asylum has been particularly punitive, including the re-introduction of temporary forms of protection for those found to be refugees. The choice to participate in higher education is an important factor for many people seeking asylum in Australia (Hartley, Fleay, Baker, Burke, & Field, 2018). Further education can provide asylum seekers with important opportunities to develop and enhance capacities and knowledge to sustain their livelihoods; aiding resettlement, social inclusion, and personal life fulfilment (Fleay, Lumbus & Hartley, 2016). Despite this, access to Australian higher education remains a persistently difficult problem for people seeking asylum who are effectively locked out because of the temporary nature of their visas (Burke, Fleay, Baker, Hartley, & Field, 2020). Because of their visa status, people seeking asylum and refugees living on temporary visas are classified as international students and are therefore pushed to pay full fees. Further, these people lose the only welfare payment they are eligible to collect if they enrol in a program of study of over 12 months duration. This has created a subclass of asylum seekers and refugees who are effectively denied access further education in Australia, unless they are able to access one of the few fee-waiver scholarships offered by some Australian universities (Hartley et al., 2018). While the gendered issues that women refugees face in accessing education have been documented (Hatoss & Huijser, 2010; Harris, Chi & Spark; 2013; Watkins, Razee & Richters, 2012), there is little known about how women from asylum seeking backgrounds access, or participate in, higher education in Australia

    Global tectonic studies: Hotspots and anomalous topography

    Get PDF
    Volcanic activity on Earth and its secular variations are compared with that on other terrestrial planets. Activity at divergent, transform, and convergent plate margins is described with particular emphasis on hot spots and flood basalts. The timing and causing of uplifting above 500 meters, which in not associated with either plate boundaries or the normal nonplate margin edges of continents is considered with particular focus on the Guyana Highlands in southern Venezuela and western British Guiana, and the Brazilian Highlands in the central, eastern, and southern parts of the country. The mode and mechanism of plateau uplifting and the re-elevation of old mountain belts and subsidence of intra-continental basins are also discussed

    A Search for Distant Galactic Cepheids Toward l=60

    Get PDF
    We present results of a survey of a 6-square-degree region near l=60, b=0 to search for distant Milky Way Cepheids. Few MW Cepheids are known at distances >~ R_0, limiting large-scale MW disk models derived from Cepheid kinematics; this work was designed to find a sample of distant Cepheids for use in such models. The survey was conducted in the V and I bands over 8 epochs, to a limiting I~=18, with a total of ~ 5 million photometric observations of ~ 1 million stars. We present a catalog of 578 high-amplitude variables discovered in this field. Cepheid candidates were selected from this catalog on the basis of variability and color change, and observed again the following season. We confirm 10 of these candidates as Cepheids with periods from 4 to 8 days, most at distances > 3 kpc. Many of the Cepheids are heavily reddened by intervening dust, some with implied extinction A_V > 10 mag. With a future addition of infrared photometry and radial velocities, these stars alone can provide a constraint on R_0 to 8%, and in conjunction with other known Cepheids should provide good estimates of the global disk potential ellipticity.Comment: 18 pages, 4 tables, 13 figures (LaTeX / AASTeX

    Design of an Automated Ultrasonic Scanning System for In-Situ Composite Cure Monitoring and Defect Detection

    Get PDF
    The preliminary design and development of an automated ultrasonic scanning system for in-situ composite cure monitoring and defect detection in the high temperature environment of an oven was completed. This preliminary design is a stepping stone to deployment in the high temperature and high pressure environment of an autoclave, the primary cure method of aerospace grade thermoset composites. Cure monitoring with real-time defect detection during the process could determine when defects form and how they move. In addition, real-time defect detection during cure could assist validating physics-based process models for predicting defects at all stages of the cure cycle. A physics-based process model for predicting porosity and fiber waviness originating during cure is currently under development by the NASA Advanced Composites Project (ACP). For the design, an ultrasonic contact scanner is enclosed in an insulating box that is placed inside an oven during cure. Throughout the cure cycle, the box is nitrogen-cooled to approximately room temperature to maintain a standard operating environment for the scanner. The composite part is mounted on the outside of the box in a vacuum bag on the build/tool plate. The build plate is attached to the bottom surface of the box. The scanner inspects the composite panel through the build plate, tracking the movement of defects introduced during layup and searching for new defects that may form during cure. The focus of this paper is the evaluation and selection of the build plate material and thickness. The selection was based on the required operating temperature of the scanner, the cure temperature of the composite material, thermal conductivity models of the candidate build plates, and a series of ultrasonic attenuation tests. This analysis led to the determination that a 63.5 mm thick build plate of borosilicate glass would be utilized for the system. The borosilicate glass plate was selected as the build plate material due to the low ultrasonic attenuation it demonstrated, its ability to efficiently insulate the scanner while supporting an elevated temperature on the part side of the plate, and the availability of a 63.5 mm thick plate without the need for lamination

    An evaluation of the spatial resolution of soil moisture information

    Get PDF
    Rainfall-amount patterns in the central regions of the U.S. were assessed. The spatial scales of surface features and their corresponding microwave responses in the mid western U.S. were investigated. The usefulness for U.S. government agencies of soil moisture information at scales of 10 km and 1 km. was ascertained. From an investigation of 494 storms, it was found that the rainfall resulting from the passage of most types of storms produces patterns which can be resolved on a 10 km scale. The land features causing the greatest problem in the sensing of soil moisture over large agricultural areas with a radiometer are bodies of water. Over the mid-western portions of the U.S., water occupies less than 2% of the total area, the consequently, the water bodies will not have a significant impact on the mapping of soil moisture. Over most of the areas, measurements at a 10-km resolution would adequately define the distribution of soil moisture. Crop yield models and hydrological models would give improved results if soil moisture information at scales of 10 km was available

    Services within a busy period of an M/M/1 queue and Dyck paths

    Get PDF
    We analyze the service times of customers in a stable M/M/1 queue in equilibrium depending on their position in a busy period. We give the law of the service of a customer at the beginning, at the end, or in the middle of the busy period. It enables as a by-product to prove that the process of instants of beginning of services is not Poisson. We then proceed to a more precise analysis. We consider a family of polynomial generating series associated with Dyck paths of length 2n and we show that they provide the correlation function of the successive services in a busy period with (n+1) customers

    Design, fabrication, and delivery of a charge injection device as a stellar tracking device

    Get PDF
    Six 128 x 128 CID imagers fabricated on bulk silicon and with thin polysilicon upper-level electrodes were tested in a star tracking mode. Noise and spectral response were measured as a function of temperature over the range of +25 C to -40 C. Noise at 0 C and below was less than 40 rms carriers/pixel for all devices at an effective noise bandwidth of 150 Hz. Quantum yield for all devices averaged 40% from 0.4 to 1.0 microns with no measurable temperature dependence. Extrapolating from these performance parameters to those of a large (400 x 400) array and accounting for design and processing improvements, indicates that the larger array would show a further improvement in noise performance -- on the order of 25 carriers. A preliminary evaluation of the projected performance of the 400 x 400 array and a representative set of star sensor requirements indicates that the CID has excellent potential as a stellar tracking device
    • …
    corecore