AI 2 Exam (September Resit) Date : 17.09.86 Time : 14.00-17.00 Examiners : Chairman : J A M Howe External : Alan Turing : Charles Babbage : ELIZA 1. Candidates in the 3rd or later year of the degrees MA(General), LLB, MSC, LBW or GCHQ should write : "I've got this far, just try and stop me now." after their names in the script book. 2. Answer four questions. Do not attempt to answer more than two questions simultaneously. 3. All questions carry equal marks. 25 marks will be awarded for each question attempted. PhDs will be awarded for any question correctly completed. ------------------------------------------------------------------------- 1) Natural Language. (a) Construct an RTN for the English language, including subordinate clauses, relative pronouns, passive sentences and all possible regional and dialect variations, including fragmentary utterances. Indicate how each sentence could be converted into 5th-order predicate calculus, with mechanisms to represent time and causality. (b) Convert the RTN above to an ATN, and add a speech-understanding mechanism of your own design. The ATN should generate as well as parse all possible sentences which could be understood by an English speaker. 2) Natural Language (a) Describe 'War & Peace' in terms of predicate calculus, explaining the meaning of each predicate that you introduce. (b) Translate Proust's 'A la recherche du temps perdu' into Schank's conceptual dependency notation. 3) Expert Systems Implement an expert system in PROLOG to diagnose all possible diseases of the higher primates. The system should be capable of conversing in English with the user, and after identifying the disease, should explain its reasoning in terms which could be understood by a naive user, and recommend appropriate therapy. The system should be aware of all drugs currently listed in the British National Formulary, and should have the option of recommending surgery if necessary. 4) Expert Systems The major problem in expert systems design is knowledge acquisition. Design a system to acquire knowledge from an expert telepathically, formalise this knowledge, and implement it as an expert system based on production rules. 5) Planning & Search (a) Represent the politics of the Middle East as a state space, taking into account the affect of Reagan, political assassination and the value of the shekel, together with any other factors you feel may be relevant. An example format for operators is given below : Operator Preconditions Delete List Add List ---------------------------------------------------------------------- bomb_libya crazy(reagan) tripoli a huge crater Search this state space to find a formula for peace. (b) Repeat the above question using problem reduction. 6) Planning & Search The monkey and bananas problem has been complicated by the following additional factors : (i) The bananas will not be ripe for two weeks. (ii) The monkey is blind. (iii) The bananas are locked in a safe. (iv) There are no suitable boxes present. (v) The monkey is afraid of heights. (vi) The floor of the room has been electrified. (vii) The monkey doesn't like bananas anyway. Describe how STRIPS could be used to solve the problem given these conditions, noting any operators you introduce. 7) Vision (a) Implement a complete vision system. You should give attention to both the low-level and high-level aspects of this system, as follows : Low-level : - resolution should be sufficient to read the small print on Insurance Policies, and the system should represent a full range of colours. High-level :- the system should be capable of analysing a scene in terms of edges, vertices, faces, regions, bodies and support relations. It should also identify any humans present in the scene by name, age and sex, and provide a reasonable guess at their shoe size and waist measurement. (b) Extend the system to make use of information from beyond the normal visual spectrum, paying special attention to the Far Ultra-Violet, and Extremely Low Frequency radio transmissions. With respect to the latter, the system should be screened against possible interference from passing nuclear submarines. 8) Vision Apply Waltz's line-labelling technique to the 'Mona Lisa', and produce a list of all bodies present. Why does it fail ? How could it be extended to take into account features present in this scene, such as the smile ?