1. FLUX

2. FLUX Predicates holds(X, Z) –Asserts X in Z knows(X, Z) –X is known to be true in Z knows_val(X, V, Z) – update(Z1, FAdd, FRemove, Z2) –Z2 = Z1 + FAdd – FRemove execute(A, Z1, Z2) –Z2 is the state after executing A in Z1

3. FLUX as a Modeling Language perform(+Action, -Perceptions). –Executes the action on the environment simulator –Returns the perception list state_update(Z1, Action, Z2, Perceptions) –Updates agent’s internal world model from Z1 to Z2, provided Action has been executed and Perceptions have been detected

4. Non FLUX modeling Action preconditions (the poss/2 or 3 predicate) –Some examples do not include it –The underlying code does not uses it –Each example models it in a different way... poss(Action, State) poss(Action, Perceptions, State) Model initialization Planing Environment simulator

5. CHR Operational Semantics in FLUX

6. Agent View World Model –Execution State –Program Rules Actions –Transitions Execution –While a final state has not been reached Apply transitions non-deterministically

7. World Model rule0 @ a, b \ c, d g0 | b0. rule1 @ x, y ==> g1 | b1. init(Z) :- holds(goal(g0), Z),..., holds(goal(gn), Z), holds(udstore(u0), Z),..., holds(udstore(un), Z), holds(bicstore(b0), Z),..., holds(bicstore(bn), Z), holds(rule(a, b \ c, d g0 | b0), Z), holds(rule(x, y ==> g1 | b1), Z).

8. Helper Predicates isBIC(true). isBIC(false). isBIC(_ == _). isUDC(X) :- not isBIC(X).

9. Helper Predicates getVars(Constraints, Variables) –getVars([p(X), q(Y,X)], W), W = [X,Y]. renameVars(HeadKeep0, HeadRemove0, Guard0, Body0, HeadKeep, HeadRemove, Guard, Body) findMatchingConstraints(Z, Constraints, Matching)

10. Helper Predicates generateMatchingEquations(Constraints, Matching, Equations) –generateMatchingEquations([c(X),d(Y)], [c(1), d(2)], W = [X == 1, Y == 2].

11. Helper Predicates entails(Z, V, C, Z1) –Z = –Z1 = –Z  Z1 –

12. Helper Predicates processBics(Z, _, [], Z). processBics(Z, LV, [B|R], Zf) :- entails(Z,LV,B, Z1), update(Z1,[bicstore(B)], [], Z2), processBics(Z2, LV, R,Zf).

13. Helper Predicates removeMatching(Z1, [], Z1). removeMatching(Z1, [C|R], Z2) :- removeMatching(Z1, R, Z12), update(Z12, [], [udstore(C)], Z2). addBody(Z1, [], Z1). addBody(Z1, [C|R], Z2) :- addBody(Z1, R, Z12), update(Z12, [goal(C)], [], Z2). addEquations(Z1, [], Z1). addEquations(Z1, [C|R], Z2) :- addEquations(Z1, R, Z12), update(Z12, [bicstore(C)], [], Z2).

14. state_update(Z1, introduce, Z2, []) :- (knows_val([X], goal(X), Z1), isUDC(X), update(Z1, [udstore(X)], [goal(X)], Z2)) ; Z1 = Z2.

15. state_update(Z1, solve, Z2, []) :- (knows_val([X], goal(X), Z1), isBIC(X), getVars([X], LV), entails(Z1, LV, X, Z2)) ; Z1 = Z2.

16. state_update(Z1, simplify, Zf, []) :- (knows_val([HeadRemove0, Guard0, Body0], rule(HeadRemove0 Guard0 : Body0), Z1), renameVars([], HeadRemove0, Guard0, Body0, _, HeadRemove, Guard, Body),...

17. findMatchingConstraints(Z1, HeadRemove,Matching), generateMatchingEquations(HeadRemove, Matching, Equations), getVars(HeadRemove, HeadVars), getVars(Guard, GuardVars), subtract(GuardVars, HeadVars, GuardLocalVars), processBics(Z1, HeadVars, Equations, Z2), processBics(Z2, GuardLocalVars, Guard, Z3),...

18. ... ((knows(bicstore(false), Z3), fail) ; (not knows(bicstore(false), Z3), removeMatching(Z3, Matching, Z4), addBody(Z4, Body, Z5), addEquations(Z5, Equations, Zf) ) ) ; Z1 = Zf.

19. CHOR Semantics in FLUX

20. CHR + O F-Atoms are syntax sugar for special UD constraints using Kifer’s codification –O:C  isa(O,C) –C::S  sub(C,S) –X[F->V]  fd(X,F,V) A new transition was added. It completes the current UD-store with information inherited by the means of inheritance Syntatic constraints: –O:C and C::S cannot appear on HeadRemove

21. Helper Predicates isFAtom(isa(_,_)). isFAtom(sub(_,_)). isFAtom(fd(_,_,_)).

22. Inherit Taxonomy Completion Taxonomy Validation Feature Inheritance validadeCycles/2 propagateSub/2 propagateIsa/2 computeInheritedFeatures/2 computeOverriding/3 cancelOverridenByCS/3

23. state_update(Z1, inherit, Zf, []) :- (not (knows_val([X], goal(X), Z1), isFAtom(X)), handleTypeInheritance(Z1, Z2), handleFeatureInheritance(Z2,Zf)) ; Z1 = Zf. handleTypeInheritance(Z1, Zf) :- propagateSub(Z1,Z2), propagateIsa(Z2,Z3), validateCycles(Z3,Zf).

24. handleFeatureInheritance(Z,Zf) :- computeInheritedFeatures(Z,Candidates), computeOverriding(Z,Candidates, CandidatesWithOutOverriden), cancelOverridenByCS(Z, CandidatesWithOutOverriden, CandidatesWithOutOverridenExt), computeSourceValue(Z,CandidatesWithOutOverridenExt, CandidatesFinal, Conflicts), transformCandidates(CandidatesFinal, NewFeatures), update(Z, NewFeatures, [], Z1), getVars(Conflicts, VarC), processBics(Z1, VarC, Conflicts, Zf).

25. Examples

26. Clyde rule1 @@ main clyde:royalElephant, royalElephant::elephant, elephant[color->gray], royalElephant[color->white) ].

27. Clyde (Results) clyde[color->white] clyde:elephant royalElephant[color->white] elephant[color->gray] royalElephant::elephant clyde:royalElephant

28. Nixon diamond rule1 @@ main quaker[policy->pacifist], republican[policy->hawk], nixon:quaker, nixon:republican.

29. Nixon Diamond (Results) Source Based Multiple Inheritance nixon : republican nixon : quaker republican[policy -> hawk] quaker[policy -> pacifist]

30. Nixon Diamond (Results) Value Based Multiple Inheritance nixon[policy->pacifist] nixon[policy->hawk] nixon:republican nixon:quaker Republican[policy->hawk] quaker[policy->pacifist] hawk==pacifist pacifist==hawk false

31. Example 2.5.1 (Adapt.) rule1 @@ main c1::c2, c2[m->a]. rule2 @@ c1[m->a] \ c2[m->a] c2[m->b].

32. Example 2.5.1 (Adapt.) (Results) c1[m->a] c2[m->b] c1::c2

33. Example 2.5.3 rule1 @@ main c1:c2, c3::c2, c2[m->a], c3[m->b]. rule2 @@ c1[m->a] ===> c1:c3.

34. Example 2.5.3 (Results) c1 : c3 c1[m-> a] c3[m->b] c2[m->a] c3 :: c2 c1 : c2