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  • Radio-loud quasars at high redshift (z ≥ 4) are rare objects in the universe and rarely observed with Very Long Baseline Interferometry (VLBI). But some of them have flux density sufficiently high for monitoring of their apparent position. The instability of the astrometric positions could be linked to the astrophysical process in the jetted active galactic nuclei in the early universe. Regular observations of the high-redshift quasars are used for estimating their apparent proper motion over several years. We have undertaken regular VLBI observations of several high-redshift quasars at 2.3 GHz (S band) and 8.4 GHz (X band) with a network of five radio telescopes: 40 m Yebes (Spain), 25 m Sheshan (China), and three 32 m telescopes of the Quasar VLBI Network (Russia)—Svetloe, Zelenchukskaya, and Badary. Additional facilities joined this network occasionally. The sources have also been observed in three sessions with the European VLBI Network in 2018–2019 and one Long Baseline Array experiment in 2018. In addition, several experiments conducted with the Very Long Baseline Array in 2017–2018 were used to improve the time sampling and the statistics. Based on these 37 astrometric VLBI experiments between 2017 and 2021, we estimated the apparent proper motions of four quasars: 0901+697, 1428+422, 1508+572, and 2101+600. Citation: Oleg Titov <i>et al </i>2023 <i>AJ</i><b> 165</b> 69

  • The Foundation Facility Point product contains five facility types, Private Hospitals, Public Hospitals, Aged Care Facilities, Educational Facilities and Emergency Management Facilities. The Foundation Facility Point Database presents the spatial location; in point format, of publicly available data. Facility Points are derived from various sources and consistency is mixed across Australia.

  • <div>Land Parcels are a spatial representation of cadastral parcels defined by the State and Territory governments of Australia. Land Parcels aggregates the complex representations unique to each jurisdiction into a consistent, seamless representation of the cadastral fabric of Australia.</div><div>Australian cadastral parcels represent the smallest legal area of land capable of sale without further approval to subdivide. These parcels can be referenced by a Land Title which offers the opportunity to link to jurisdictional information that can include: the certificate of title or crown lease, valuation information, land descriptions and more, through the State’s or Territory’s Land Registry.</div> National Base Land Parcels (the <b>Data</b>) is available to Commonwealth Government users of the Digital Atlas of Australia. Contact <a href = "mailto: DigitalAtlas@ga.gov.au">DigitalAtlas@ga.gov.au</a> for access.

  • <div>National Exposure Information System (NEXIS) Residential Dwelling Density is a set of four raster layers representing the density of residential dwellings across Australia at different scales and resolutions. A dwelling is defined as self-contained suites of rooms including cooking and bathing facilities and intended for long-term residential use. Such dwelling units include houses-detached buildings used for long-term residential purposes-and other dwellings including flats. NEXIS collates the best publicly-available information, statistics, spatial and survey data into comprehensive and nationally-consistent exposure information datasets. Where data is limited, models are used to apply statistics based on similar areas. Exposure Information products are created at the national, state or local level to understand the elements at risk during an event or as a key input for analysis in risk assessments. NEXIS products are not intended for operational purposes at the building or individual feature level. Its strength is to provide consistent aggregated exposure information for individual event footprints or at standard community, local, state and national geographies such as the Australian Bureau of Statistics (ABS) Statistical Areas (SA) or Local Government Areas (LGA). NEXIS Building exposure information consists of Residential, Commercial and Industrial buildings. This information can be used to understand the type, use, age and structural characteristics such as number of storeys, roof type and wall type of the building stock nationally. Building exposure information can also be used to estimate population attributes such as the number of occupants, household income and other demographic indicators, as well as economic impacts based on building construction and replacement costs. The NEXIS Residential Dwelling Density is a national grid-based representation derived from the number and distribution of dwellings produced from the NEXIS residential buildings data. </div><div><br></div><div>Dwelling density is available as a web service displaying the aggregate number of dwellings, at four different raster scales and resolutions, to show the distribution and density of residential dwellings across Australia. Resolutions include 100m, 500m, 1km and 2km rasters.</div><div><br></div><div>Resolutions:</div><div>1. Number of residential dwellings per 100sqm. Visible at zoom scales 1:250,000 minimum with no maximum. </div><div>2. Number of residential dwellings per 500sqm. Visible at zoom scales 1:700,000 minimum with 1:250,001 maximum.</div><div>3. Number of residential dwellings per 1km square. Visible at zoom scales 1:3,000,000 minimum with 1:700,001 maximum. </div><div>4. Number of residential dwellings per 2km square. Visible at zoom scales with no minimum and 1:3,000,001 maximum</div><div>&nbsp;</div><div>This product is based on NEXIS version 15 (2024) data.</div><div><br></div>

  • <div>Major Roads is a subset of the National Roads by Geoscape dataset, filtered for highways, arterial and sub-arterial roads. National Roads by Geoscape is a digital representation of the road network of Australia. National Roads contains linear features to describe surfaces that have been improved to enable vehicular, pedestrian and bicycle transportation on land and ferry routes that enable vehicles to cross water bodies. National Roads does not include railways, tramways, driveways or passenger ferry routes.</div><div><br></div><div>This dataset provides an optimised aggregated national view of road geometry and attribution. The dataset is created from multiple sources including jurisdictional data which is revised regularly and supplied in varying formats and at different levels of quality.</div><div><br></div><div>The area covers the land mass of Australia, including offshore islands. Norfolk Island is currently not included.</div>

  • <div>A set of Foundation Spatial Data Framework (FSDF) datasets built as Linked-Data RDF triples. Includes Electrical Infrastructure, Emergency Facilities, and Placenames. (Sits alongside other Geoscience RDF data bases and their APIs). An API built over this RDF database supplies mapped detail of each individual feature along with metadata, geometry, alternate views and profiles. RDF provides a standardized schema for use with any other datasets based on RDF Triples. The API is human readable and machine readable. Machine readability allows web based APIs and dashboards to consume the data in a number of standardized formats, to value add and build specialized tools for a great variety of uses, including emergency use dashboards and higher level APIs.</div><div><br></div><div>The API conforms with the OGC LA API standard and uses VocPrez and SpacePrez technology.</div>

  • Linked Data refers to a collection of interrelated datasets on the Web expressed in a standard structure. These Linked Data and relationships among them can be reached and managed by Semantic Web tools. Linked Data enables large scale integration of and reasoning on data on the Web. This cookbook is to documents the processes and workflows required to create a Linked Data API for a dataset in the Foundation Base Project in Geoscience Australia (GA) and further publish it on the AWS.

  • The Foundation Rail Infrastructure feature dataset is part of the Foundation Spatial Data Framework theme for Transport. The Foundation Rail Infrastructure feature dataset is specifically made up of Rail line features (Railways, Rail Sidings and Tramline including Light Rail) and Rail points (Stations). This feature class represents a national aggregation of the spatial locations and attributes of line and point features, of publicly available data. Rail Infrastructure information has been derived from various sources provided by data custodians including Spatial Services (NSW), Department of Natural Resources, Mines and Energy (QLD), Department of Environment, Land, Water and Planning (VIC), Land Tasmania (TAS) and Department of Infrastructure and Transport (SA). The coverage is across all states and territories however due to restrictive licensing, Geoscience Australia data was used as the source data for Western Australia (lines and points), the Northern Territory (lines and points) and South Australia (points). Data published by Victoria falling within South Australia has been included (points). Further information on datasets provided by State and Territory custodians can be found under Source Information in the metadata statement.

  • This web service provides access to the Foundation Rail Infrastructure dataset. This contains the spatial locations and attributes of Railway lines and Railway Station points.

  • The Australian Electoral Commission (AEC), Commonwealth Electoral Divisions are federal electoral divisions. AEC electoral divisions are areas legally prescribed for the purpose of returning members to the House of Representatives. Commonwealth Electoral Divisions may change as the AEC revise their boundaries. Where this occurs, Commonwealth Electoral Divisions will be updated annually. The 2021 Commonwealth Electoral Divisions remain current at this time. There are 170 Commonwealth Electoral Divisions covering the whole of Australia without gaps or overlaps. Geoscience Australia to re-host the Commonwealth Electoral Division Boundaries for the purpose of the Digital Atlas of Australia Beta release in June 2023.