112 research outputs found

    BIRD - A Microsatellite for Hot Spot Detection

    Get PDF
    The BIRD mission of the German Aerospace Centre shall demonstrate the scientific and technological value and the technical and programmatic feasibility of a remote sensing small satellite mission under low budget constraints. The payload -a new generation of cooled infrared detectors- is adapted to the mission objective - the investigation of hot spots caused by forest fires or volcanic activities completed by the diagnosis of vegetation conditions and changes. BIRD -the Bispectral Infra-Red Detector- is a three-axis stabilised spacecraft within a volume of 0.21 m3 and a mass of 88 kg. In flight configuration with one fixed and two deployed solar panels, providing 40 W average and 200 W peak power, the spacecraft dimensions are 620x 1600x 620 mm3 • Although compatible to several launchers due to the highly compact design, the launch is scheduled for mid 2000 as a piggy-back payload. To fit in this time scale a modular design was chosen for parallel development, manufacturing and integration of all functional segments. The article gives an overview of the mission objectives and some of the main design aspects as well as shows the status of work of the space segment

    International home economics

    Get PDF
    The conference was planned to serve the interests of those who wish to work in home economics programs abroad and those who are concerned with the education of international students in the universities and colleges of the United States. Approximately 165 home economists from other states and from foreign countries I including the African and Latin American countries I participated in the conference.https://lib.dr.iastate.edu/card_reports/1026/thumbnail.jp

    Circular 30

    No full text
    Modern hybrid lilies are among the showiest perennials that can be grown by the interior Alaska gardener. There are several groups, or classes, of lilies available, not all of which are hardy here. Within a given group, there are many cultivars, which may or may not be hardy. We will, therefore, describe for you in this circular a number of lily cultivars which have proven to be hardy at the Agricultural Experiment Station at Fairbanks, and indicate those groups of lilies in which the adventurous gardener would be most likely to find additional hardy varieties

    Tensile properties of concrete at very early ages

    No full text
    Proper knowledge of tensile properties of concrete from very early ages is essential for effective control of not only early-age cracking but also of residual stress due to restrained early-age deformation as well as for demolding and handling of young concrete members in the precast industry. Despite significant past research, such knowledge is currently inadequate and based on experimental data with questionable reliability, due mainly to the considerable challenges in testing early-age concrete. This paper first highlights the challenge and importance of collecting reliable test data on full tensile stress-deformation curves for very early-age concrete. Through identifying and effectively addressing critical drawbacks in previous test setups, an improved direct tensile testing system that can reliably capture simultaneously stress and deformation of concrete from the age of several hours after mixing has been successfully developed. Key features of the improved setup, including the air-bearing box for friction minimisation and digital image correlation for non-contact full-field deformation capturing, are then reported in the paper. Based on the newly collected data, fundamental tensile properties of concrete at very early ages are re-assessed and presented. Such properties include tensile strength, Young’s modulus, strain at peak stress, fracture energy, performance under cyclic loading and tensile relaxation

    The DLR Small Satellite Mission BIRD

    No full text
    For hot spot events as forest and vegetation fires, volcanic activity or burning oil spills and coal seam a dedicated space instrumentation does not exist. Sensors are used now for the observation of these events have some drawbacks because they are not designed for the hot spot investigation. For the near future missions with a new generation of cooled infrared array sensors are planned. The BIRD (Bispectral Infrared Detection) mission will answer a lot of technological questions related to the operations of the infrared sensors in space. An other primary mission objective consists in the investigation of vegetation fires from space by means of these infrared sensors. New concepts of operations and new methods of the data evaluation of hot spots will be demonstrated by the BIRD mission. Last but not least new methods and knowledge in the remote sensing and evaluation of vegetation condition and changes from space will be developed within the BIRD mission. The BIRD mission is a small satellite mission with technological and scientific objectives
    • …
    corecore