SAQA All qualifications and part qualifications registered on the National Qualifications Framework are public property. Thus the only payment that can be made for them is for service and reproduction. It is illegal to sell this material for profit. If the material is reproduced or quoted, the South African Qualifications Authority (SAQA) should be acknowledged as the source.
SOUTH AFRICAN QUALIFICATIONS AUTHORITY 
REGISTERED UNIT STANDARD: 

Demonstrate an understanding of topology for storing spatial data 
SAQA US ID UNIT STANDARD TITLE
258649  Demonstrate an understanding of topology for storing spatial data 
ORIGINATOR
SGB Geographical Information Sciences 
PRIMARY OR DELEGATED QUALITY ASSURANCE FUNCTIONARY
-  
FIELD SUBFIELD
Field 12 - Physical Planning and Construction Physical Planning, Design and Management 
ABET BAND UNIT STANDARD TYPE PRE-2009 NQF LEVEL NQF LEVEL CREDITS
Undefined  Regular  Level 6  Level TBA: Pre-2009 was L6 
REGISTRATION STATUS REGISTRATION START DATE REGISTRATION END DATE SAQA DECISION NUMBER
Reregistered  2015-07-01  2018-06-30  SAQA 10105/14 
LAST DATE FOR ENROLMENT LAST DATE FOR ACHIEVEMENT
2019-06-30   2022-06-30  

In all of the tables in this document, both the pre-2009 NQF Level and the NQF Level is shown. In the text (purpose statements, qualification rules, etc), any references to NQF Levels are to the pre-2009 levels unless specifically stated otherwise.  

This unit standard does not replace any other unit standard and is not replaced by any other unit standard. 

PURPOSE OF THE UNIT STANDARD 
This unit standard has been developed for the GIS occupational area and is intended for persons who aim to achieve career advancement by gaining GIS skills leading to qualification based on unit standards. A person who has successfully completed this unit standard will be able to understand the theory and application of topology in relation to storage of spatial data.

A person credited with this unit standard is able to:
  • Demonstrate an understanding of components of the topology model.
  • Explain different topological characteristics.
  • Demonstrate an understanding of the advantages of storing topology for spatial data.

    Specific range statements are provided in the body of the unit standard where they apply to particular specific outcomes or assessment criteria. 

  • LEARNING ASSUMED TO BE IN PLACE AND RECOGNITION OF PRIOR LEARNING 
    The credit calculation is based on the assumption that learners are already competent in terms of the following outcomes or areas of learning when starting to learn towards this unit standard:
  • Understanding of the context of GI Science.
  • Understanding of the basic principles of spatial data.
  • Communication at NQF Level 5.
  • Mathematical Literacy at NQF Level 5. 

  • UNIT STANDARD RANGE 
    Range statements are included with specific outcomes as necessary. 

    Specific Outcomes and Assessment Criteria: 

    SPECIFIC OUTCOME 1 
    Demonstrate an understanding of components of the topology model. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    Different historical topology spatial data models are explained to illustrate the components of the topology model. 
    ASSESSMENT CRITERION RANGE 
    Including but not limited to GBF/DIME, PolyVrt, TIGER and Freeman-Huffman chain codes.
     

    ASSESSMENT CRITERION 2 
    The OGIS Simple Feature Classification topology model is described with relation to the topology model. 

    ASSESSMENT CRITERION 3 
    The spaghetti spatial data model is described with relation to the topology model. 

    SPECIFIC OUTCOME 2 
    Explain different topological characteristics. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    The topological characteristics of network structures are explained with regard to topological characteristics. 

    ASSESSMENT CRITERION 2 
    The application of tree structures is explained with regard to topological characteristics. 

    ASSESSMENT CRITERION 3 
    The application of network structures is explained with regard to topological characteristics. 

    ASSESSMENT CRITERION 4 
    The topological characteristics of tree structures are explained with regard to topological characteristics. 

    SPECIFIC OUTCOME 3 
    Demonstrate an understanding of the advantages of storing topology for spatial data. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    The advantages of each data structure are understood and explained. 
    ASSESSMENT CRITERION RANGE 
    Including but not limited to GBF/DIME, PolyVrt, TIGER.
     

    ASSESSMENT CRITERION 2 
    The disadvantages of each data structure are understood and explained in terms of storing topology for spatial data. 

    ASSESSMENT CRITERION 3 
    Describe the advantages and disadvantages of Freeman-Huffman chain codes in relation to raster data. 


    UNIT STANDARD ACCREDITATION AND MODERATION OPTIONS 
  • Anyone assessing a learner against this unit standard must be registered as an assessor with the relevant ETQA.
  • Any institution offering learning that will enable achievement of this unit standard must be accredited as a provider through the relevant ETQA by SAQA.
  • Moderation of assessment will be overseen by the relevant ETQA according to the moderation guidelines and the agreed ETQA procedures. 

  • UNIT STANDARD ESSENTIAL EMBEDDED KNOWLEDGE 
    Essential embedded knowledge will be assessed through assessment of the specific outcomes in terms of the stipulated assessment criteria. Candidates are unlikely to achieve all the specific outcomes, to the standards described in the assessment criteria, without knowledge of the listed embedded knowledge. This means that for the most part, the possession or lack of the knowledge can be directly inferred from the quality of the candidate's performance. Where direct assessment of knowledge is required, assessment criteria have been included in the body of the unit standard. 

    UNIT STANDARD DEVELOPMENTAL OUTCOME 
    N/A 

    UNIT STANDARD LINKAGES 
    N/A 


    Critical Cross-field Outcomes (CCFO): 

    UNIT STANDARD CCFO IDENTIFYING 
    Solve problems. 

    UNIT STANDARD CCFO WORKING 
    Work effectively with others as a member of a team/group/organisation or community. 

    UNIT STANDARD CCFO ORGANISING 
    Organise and manage oneself and one's activities responsibly and effectively. 

    UNIT STANDARD CCFO COLLECTING 
    Collect, organise and critically evaluate information. 

    UNIT STANDARD CCFO COMMUNICATING 
    Communicate effectively using visual, mathematics and language skills in the modes of oral and written presentations. 

    UNIT STANDARD CCFO SCIENCE 
    Use science and technology effectively and critically (showing responsibility towards the environment and health of others). 

    UNIT STANDARD CCFO DEMONSTRATING 
    Display an understanding of the world as a set of related systems. 

    UNIT STANDARD CCFO CONTRIBUTING 
    Contribute to the full development of each learner and the social and economic development of society at large. 

    UNIT STANDARD ASSESSOR CRITERIA 
    N/A 

    REREGISTRATION HISTORY 
    As per the SAQA Board decision/s at that time, this unit standard was Reregistered in 2012; 2015. 

    UNIT STANDARD NOTES 
    Terminology:

    Node:
  • Any co-ordinate point shared between two or more features.

    Chain:
  • Any series of points, shared between two or more features. Chains have direction, starts and ends in nodes and are often defined by the polygons to the left and right of the chain. Chains are also referred to as Arcs.

    Notes to Assessors:
  • Take care not to impose the terminology of particular vendors onto learners. Rather focus on the conceptual understanding of the topic. 

  • QUALIFICATIONS UTILISING THIS UNIT STANDARD: 
      ID QUALIFICATION TITLE PRE-2009 NQF LEVEL NQF LEVEL STATUS END DATE PRIMARY OR DELEGATED QA FUNCTIONARY
    Elective  63589   National Diploma: Geographical Information Science  Level 5  NQF Level 05  Reregistered  2018-06-30  CETA 
    Elective  63689   Bachelor of Arts: Geographical Information Science  Level 6  Level TBA: Pre-2009 was L6  Reregistered  2018-06-30   
    Elective  63711   Bachelor of Geographical Information Science (GISc)  Level 7  NQF Level 07  Reregistered  2018-06-30   


    PROVIDERS CURRENTLY ACCREDITED TO OFFER THIS UNIT STANDARD: 
    This information shows the current accreditations (i.e. those not past their accreditation end dates), and is the most complete record available to SAQA as of today. Some Primary or Delegated Quality Assurance Functionaries have a lag in their recording systems for provider accreditation, in turn leading to a lag in notifying SAQA of all the providers that they have accredited to offer qualifications and unit standards, as well as any extensions to accreditation end dates. The relevant Primary or Delegated Quality Assurance Functionary should be notified if a record appears to be missing from here.
     
    NONE 



    All qualifications and part qualifications registered on the National Qualifications Framework are public property. Thus the only payment that can be made for them is for service and reproduction. It is illegal to sell this material for profit. If the material is reproduced or quoted, the South African Qualifications Authority (SAQA) should be acknowledged as the source.