ACT Geographic Data Directory
| ACT Geographic Data Directory |
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Note: This dataset description is metadata (data about data) which describes the actual dataset in accordance with the ANZLIC (Australia New Zealand Land Information Council) Core Metadata Guidelines
ANZLIC unique identifier: ANZAC0236001049
Title: DUS Corporate Geographic Database - Built Environment Kerbs
Custodian: ACT Government, Department of Urban Services, Customer Service and Information, Information Management Branch
Jurisdiction: Australian Capital Territory
Abstract:
Roads ACT, a business unit within DUS is the custodian of the source data for road kerbs. The data set is managed on behalf of Roads ACT by ACTLIC through their Spatial Data Management System (SDMS). This layer is a modified version of the Roads ACT Kerb data. It has been created to the specification agreed to as a part of the GIM Strategy and included in the Corporate Geographic Database (CGD) created under that strategy. The CGD creates a fully homogeneous and integrated set of core geographic information which uses Oracle SDO. The CGD is a read only Oracle spatial database hosted within the ACT Government's production computing environment and is capable of being directly read by most GIS software. The CGD stores data in both the ACT Stromlo Projection and MGA94 projection for Zone55. This data set includes the following attributes: Kerb_ID, ANZLIC_ID, Source_ANZLIC_ID, Feature_Type_Code, Create_Date, Length and Feature_Instance_Metadata_ID.
ANZLIC search words:
Spatial domain:
Geographic extent name: AUSTRALIAN CAPITAL TERRITORY - ACT - State or Territory - Australia
Note: The format for each Geographic extent name is: Name - Identifier - Category - Jurisdiction (as appropriate) See GEN Register
Beginning date: 2003-07-27
Ending date: Current
Progress: Complete
Maintenance and update frequency: Irregular
Access constraints:
The Corporate Geographic Database has been compiled as a part of the DUS Geographic Information Management Strategy. Community access data sets in the database are available for internal use by agencies in the ACT Government, including presentation through ACT Government web sites. Use outside of this should be approved by the supplier of the source data (ACTLIC). This data set is classified as Community Access.
Lineage:
The Kerb table has been created from the ROAD_KERBS table in the ACTPLA Spatial Data Management System (SDMS). The original data was exported from SDMS (Oracle 8.1.6) with a selection on the attribute Current_Lifecycle_Stage to eliminate unwanted historic data. The lifecycle types which were preserved were Entered. This was then imported into a translation table to enable some of the original attributes to be removed and verification checks to be performed. To ensure that the data was logically consistent, this table was converted through FME to a Shape file. This processes converted circular curves to a series of small chords, significantly increasing the number of vertices. This coverage was cleaned using a tolerance of 5mm and then generalised using the Douglas-Poiker algorithm with a 2mm tolerance to reduce the number of vertices and ensure alignment with the original data at a scale of 1:10 or better. The result was then converted back to Oracle Spatial using an Arc Coverage import to FME. Further verification was performed at this stage. Subsequently a similar process is used to introduce incremental changes with retired instances transferred to a second version of the database. Contact the DUS IM Branch for further information on these processes.
Positional accuracy:
A prospective user should contact the supplier of the source data set (ACTLIC) for details of the horizontal accuracy. The errors introduced through the conversion process to this data set are less than 0.1m. The Z value is not stored.
Attribute accuracy:
There are no attributes other than the ID and standard Corporate Geographic Database attributes recorded.
Logical Consistency:
The source data is managed in a way which largely eliminates logical inconsistencies. Some minor variations may be introduced in the transfer process, however all geometry is then cleaned using ArcInfo software prior to transfer to the final Oracle Spatial format. The clean tolerance used is 5mm.
Completeness:
The data provided by the source custodian is managed in a rigorous manner and is in a constant state of update. The latest version of this data is used for each update. NOTE: The attributes of Source_ANZLIC_ID, Feature_Type_Code and Feature_Instance_Metadata_ID have not been populated.
Metadata date: 2007-11-30
Metadata reference: http://indexgeo.net/asdd/act/ANZAC0236001049.html
This dataset description can be discovered via the Australian Spatial Data Directory (ASDD)