pdf 820Kb - INSEAD CALT

More documents

Recommendations

Info

Evaluation report of the use of Onto-Logging platform in the user site Deliverable ID: D8b Page : 58 of 110 Version: 1.0 Date: 27 january 2004 Status: Final Confid.: Public the users would need, or which concepts may be interesting for them. These allow us to add those concept missed in the original ontology. Once a first draft of the new ontology has been sketched, it is better to work directly with the Ontologging system tools, which provide a richer environment to redesign ontologies, even if the new ontology is not totally defined. Step 2 – From paper to Ontologging: ‘rough’ migration The ‘sketched’ ontology was transferred to the system using KAON. The original ontology was used as a reference, since some of the concepts were the same. Once the first version was introduced in the system with KAON, the next task was defining the mappings or translations required to move the already existing data from the original ontology to the new one. This process was ma de using the ORA (Ontologging Reconciliation Agent), programming in XML the required mappings. This tool allowed avoiding the loss of a huge amount of data, already introduced in the original ontology. However, this migration process does not allow to map all the instances to their corresponding concept, because when a concept from the original ontology is mapped to different concepts in the new ontology, it may be difficult to establish a way to distinguish the to which concept the instances must be assigned. Therefore, it will be necessary an additional work to separate this instances in a later stage. Step 3 – Polishing the ontology – ‘sharp’ migration Although ORA allowed moving an important amount of data, the result still required some additional work of adjustment and tuning. The DUI was used at this stage for completing the work. The DUI was used: • To check if its design is correct from the point of view of the final users • To complete the data population with some instances that were not present in the original Ontology. Indeed the new Ontology had also introduced new concepts and new relations, for which associated instances and relationships had to be created. At this final stage, the work was an iterative cycle between KAON (the Ontology editor) the DUI, and sometime the ORA (with was used to move some data not included in the ‘gross’ migration). Following is the iteration cycle:
Evaluation report of the use of Onto-Logging platform in the user site Deliverable ID: D8b Page : 59 of 110 Version: 1.0 Date: 27 january 2004 Status: Final Confid.: Public • The DUI was used to review a part of the ontology and to see which instances were required to complete the attributes or relationships that are important and have not been included in the new ontology. o We had to check if those required instances or values where present in the original ontology and their links had been destroyed in the migration process. For this purpose , the KAON was used to navigate the original ontology to check the old values of these properties or attributes. This procedure allowed us to locate those instances that in the migration process were moved to a wrong concept, so we can take note of them to change the parent concept later with the KAON. • We created a lot of instances to complete the empty attributes or relationships, using the DUI. These instances were new, and were not present in the original ontology. • We modified the instances already existing in the original ontology but moved to a wrong concept in the new one. Using the KAON, we changed their parent concept to the correct one. Later, again with the DUI, we relate appropriately these instances to others. • Sometimes, it was easier to re-create the instance from scratch, just using the instance in the original ontology as a reference to copy its attributes and to re -link its relationships. This is so because sometimes we want also to change the tag that identifies the instance, perhaps because the original was wrong according to the nomenclature established. Therefore, in the iteration we kept going over the instances of a concept, checking if all the key relations were established, filling the pending values. This process implied the creation of new instance, which again meant reviewing all their properties and perhaps creating new instances. This process was repeated over the instances of other concept. Once all the data was complete, the ontology was again ready to be used for all the users. 5.2.2.2 Analysis of the redesign process The Ontology resulting from the re-engineering was considered of an adequate level of quality, and in particular made the final system usable by the end users. This re-engineering represented a major effort, and took several weeks to be completed. This redesign was very useful in that it provided the setting for investigating deeply and concretely the issues related to Ontology design, one of the most critical element in the design of an ontology-based system. Indeed, we can consider that reengineering represents a facet inherent to the Ontology design process, and not only an operation that we had to carry out in this project because we would been to hasty in design of the initial ontology. Ontologies are in any case subject to evolutions (this flexibility is actually one of the main reason of using ontology-based system) during the lifecycle of a knowledge management system. Ontology building is also inherently
Page 1 and 2:
The ONTO-LOGGING Consortium consist
Page 3 and 4:
Evaluation report of the use of Ont
Page 5 and 6:
Executive Summary Evaluation report
Page 7 and 8: Evaluation report of the use of Ont
Page 53 and 54: • List of connected users to the
Page 57: Evaluation report of the use of Ont
Page 67 and 68: 5.5.1 Description of the evaluation
Page 69 and 70: 6 Discussion and Conclusions Evalua
Page 75 and 76: 8 Annex Evaluation report of the us
Page 93 and 94: esolver consultas. C42 Existen axio
Page 103 and 104: 1 The functionalities provided by D
Page 109 and 110:
Evaluation report of the use of Ont
show all

pdf 820Kb - INSEAD CALT

Create successful ePaper yourself

Delete template?

Save as template?