COM362 Knowledge Engineering Exam Revision 1 John MacIntyre

COM362 Knowledge Engineering Exam Revision 2 Exam Structure Answer any 5 from 8 questions All questions worth 20 marks Questions divided into parts: First part easy, bullet point answers Second part a little more detailed, but could still be answered with bullet points Third part requires demonstration of critical understanding of theory and how it can be applied

COM362 Knowledge Engineering Exam Revision 3 Points to Remember Use illustrations to help your answers! Look at how the marks are divided and allocate time accordingly, eg: Three hours = 180 mins Subtract 15 mins for reading paper, 15 mins for review at end = 150 mins = 30 mins per question Generally three parts, say 6, 6, 8 marks Perhaps 8, 8, 14 mins?

COM362 Knowledge Engineering Exam Revision 4 Example Q1: Part (a) Explain the difference between data, information, and knowledge. Use examples to illustrate your answer. (6 marks)

COM362 Knowledge Engineering Exam Revision 5 Q1a: Issues to Address Give a definition of knowledge! Stress that data are the raw values; information is the processed data; knowledge is the deeper understanding of the information Use examples! Eg data - 5 deg C, information - it is cold, knowledge - because it is cold need to wear warm clothes.

COM362 Knowledge Engineering Exam Revision 6 Q1a: Issues to Address Therefore knowledge includes both data and information Mention different types of knowledge Answers have to be brief - don’t write an essay for 6 marks!

COM362 Knowledge Engineering Exam Revision 7 Example Q1: Part (b) Explain what the term “Ontology” means in terms of Knowledge Engineering. Use examples to illustrate your answer. (6 marks)

COM362 Knowledge Engineering Exam Revision 8 Q1b: Issues to Address Defines vocabulary (set of standard terms), structure of statements, and semantic interpretation of terms. Mention different types of ontology, eg: Terminological Ontology, Information Ontology, Knowledge Modelling Ontology, Domain Ontology etc Use examples: ship design ontology, enterprise ontology, electrical network ontology etc

COM362 Knowledge Engineering Exam Revision 9 Example Q1: Part (c) You have been asked to head a team of knowledge engineers developing a large knowledge-based system to assist ship designers. You must minimise the amount of time taken to develop the system. Discuss the approach you would take to knowledge modelling, with specific reference to standardisation, compatability and software re-use. (8 marks)

COM362 Knowledge Engineering Exam Revision 10 Q1c: Issues to Address  Discussion of the problems of working with large teams of engineers and need for standardisation of design and modelling approach  Development of Knowledge Level Model, and the use of Knowledge Modelling Ontologies for standardisation of design  Discussion of different types of Ontologies, such as Domain and Problem Solving, and the fact that these are re-usable components

COM362 Knowledge Engineering Exam Revision 11 Q1c: Issues to Address  Use of existing components from an appropriate ontology to shorten development time and give compatability where a team of engineers are developing code.  Additional marks for discussion of Knowledge Level Representation Languages, and how they are used to express both Knowledge Level Models and Knowledge Modelling Components.

COM362 Knowledge Engineering Exam Revision 12 Example Q2: Part (a) Describe the processes of forward and backward chaining. Use examples to illustrate your answer. (6 marks)

COM362 Knowledge Engineering Exam Revision 13 Q2a: Issues to Address  FC: enter data, fire FC rules, infer new values from rule actions, add new values to knowledge base, fire all rules which can now be fired, repeat until all rules which can fire have been fired. Therefore DATA driven.  BC: state primary goal to be satisfied, find rules to satisfy it, fire rules and source sub-goals needed to satisfy those rules, get data at run- time if needed to resolve goals, repeat until all sub-goals and consequently primary goal are satisfied. Therefore GOAL driven.

COM362 Knowledge Engineering Exam Revision 14 Example Q2: Part (b) Discuss the advantages and disadvantages of a backward chaining approach to the problem of fault diagnosis for automobiles. (6 marks)

COM362 Knowledge Engineering Exam Revision 15 Q2b: Issues to Address  Advantages: goal driven problem (specify fault), allows interaction with the user at run-time to get necessary information; will produce a specific outcome.  Disadvantages: does not produce all possible outcomes.

COM362 Knowledge Engineering Exam Revision 16 Example Q2: Part (c) You are designing a knowledge-based system for decision support in a nuclear power station The plant operators wish to know everything possible about the state of the plant at any given time. Which inference mechanism would you use? Explain your choice. Discuss any other important issues for the knowledge engineer in designing safety critical systems.(8 marks)

COM362 Knowledge Engineering Exam Revision 17 Q2c: Issues to Address Best choice should be forward chaining, with justification on the need to know everything possible from the given data at any time Some latitude if backward chaining chosen on the basis of the need for specific fault information

COM362 Knowledge Engineering Exam Revision 18 Q2c: Issues to Address Safety critical issues: auditability and traceability need for high accuracy and reliability problems with testing and validating large knowledge-bases possible conflicts human issues such as interface

COM362 Knowledge Engineering Exam Revision 19 General Exam Technique READ THE QUESTION!! Allocate sufficient time Bullet points for shorter parts More thoughtful discussion for longer parts Review answers if you have time left Use illustrations Use examples If you struggle for time - put SOMETHING down - you WILL pick up marks for this!