M. A. Orgun, W. W. Wadge, and W. Du. Chronolog(Z): Linear-time logic programming. In O. Abou-Rabia, C. K. Chang, and W. W. Koczkodaj, editors, Proc. of the fifth International Conference on Computing and Information, pages 545--549. IEEE Computer Society Press, 1993.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....lucid way. In this paper we introduce and present the semantics of Disjunctive Chronolog, a temporal disjunctive logic programming language. Our starting point is the temporal language Chronolog, introduced by W. W. Wadge[Wad88] whose semantics have been systematically developed by M. Orgun[Org91, OW92, OWD93]. The proposed formalism, Disjunctive Chronolog, is capable of expressing time related uncertainty of different forms: Event uncertainty. Consider for example the curriculum of a computer science department, which requires from students to have taken Discrete Mathematics before they register to ....

....need the notion of a canonical temporal atom[Org91] A canonical temporal atom is a formula of the form A for some n 0, where A is an atomic formula. A canonical disjunctive temporal clause is a disjunctive temporal clause whose temporal atoms are canonical temporal atoms. As in Chronolog [Org91, OWD93], every disjunctive temporal clause can be transformed into a (possibly infinite) set of canonical disjunctive temporal clauses. This can be done by applying where n 0, to the clause, and then using the axioms of TL to distribute the temporal reference so as to be applied to each individual ....

M. A. Orgun, W. W. Wadge, and W. Du. Chronolog(Z): Linear-time logic programming. In O. Abou-Rabia, C. K. Chang, and W. W. Koczkodaj, editors, Proc. of the fifth International Conference on Computing and Information, pages 545--549. IEEE Computer Society Press, 1993.

....systems. For example, consider the following Chronolog [4] program simulating the operation of the traffic lights: first light(green) next light(amber) light(green) next light(red) light(amber) next light(green) light(red) However, Chronolog as well as most temporal languages [1, 5, 6, 7, 8, 9, 10] are based on linear flow of time, a fact that makes them unsuitable for certain types of applications. For example, as M. Ben Ari, A. Pnueli and Z. Manna indicate [11] branching time logics are necessary in order to express certain properties of non deterministic programs. Moreover, as it is ....

....Intuitively, a canonical temporal instance of a clause is an instance in time of the corresponding temporal clause. Notice that the notion of canonical temporal atoms clauses instances have been initially introduced in the context of the linear time temporal logic programming language Chronolog [3, 6]. Notice that a canonical temporal instance of a clause can also be obtained by the following procedure: apply a canonical temporal reference to the clause itself; use the temporal operator distribution axioms to distribute the temporal reference so as to be applied to each individual temporal ....

M. A. Orgun, W. W. Wadge, and W. Du. Chronolog(Z): Linear-time logic programming. In O. Abou-Rabia, C. K. Chang, and W. W. Koczkodaj, editors, Proc. of the Fifth International Conference on Computing and Information, pages 545--549. IEEE Computer Society Press, 1993.

....from each moment, there exist 3 many possible alternative futures. 3 Temporal Logic Programming 3.1 Linear Time Temporal Logic Programming The logic programming languages presented in this section are based on linear time temporal logics. 3.1. 1 Chronolog Chronolog [Org91, OW92a, OW92b, OW93, OWD93] is a temporal logic programming language based on a simple temporal logic in which time is linear and discrete. Chronolog has two temporal operators: The operator first, which refers to the first moment in time, and the operator next, which refers to the next moment in time. Chronolog uses the ....

....goal. The substitution in this matching is the empty substitution 1 = fg. The answer computed in this derivation is the composition of the substitutions 0 and 1 which gives L = amber. TiSLD resolution is a sound and complete proof procedure. Extensions of Chronolog have been introduced in [OWD93, OW94] In particular, in [OWD93] Chronolog(Z) is introduced, which is based on a linear time temporal logic with unbounded past and future with the set Z of integers as the collection of moments in time. Besides the temporal operators first and next of Chronolog, Chronolog(Z) has also an ....

[Article contains additional citation context not shown here]

M. A. Orgun, W. W. Wadge, and W. Du. Chronolog(Z): Linear-time logic programming. In O. Abou-Rabia, C. K. Chang, and W. W. Koczkodaj, editors, Proc. of the Fifth International Conference on Computing and Information, pages 545--549. IEEE Computer Society Press, 1993.

....systems. For example, consider the following Chronolog [Wad88] program simulating the operation of the traffic lights: first light(green) next light(amber) light(green) next light(red) light(amber) next light(green) light(red) However, Cronolog as well as most temporal languages [OM94, Hry93, OWD93, Bau93, OW92, Brz91, Brz93, GRP96] are based on linear flow of time, a fact that This work has been funded by the Greek General Secretariat of Research and Technology under the project TimeLogic of PiENE Delta 0 95, contract no 1134. This paper appears in the Proceedings of the First International Joint Conference on ....

....BSLDresolution. Definition3. A canonical temporal atom is a formula first next i 1 Delta Delta Delta next i n A, where i 1 ; i n 2 S and n 0, and A is an atom. A canonical temporal clause is a temporal clause whose temporal atoms are canonical temporal atoms. As in Chronolog [Org91, OWD93], every temporal clause can be transformed into a (possibly infinite) set of canonical temporal clauses. This can be done by applying first next i 1 Delta Delta Delta next i n , where i 1 ; i n 2 S and n 0, to the clause and then using the axioms of BTL, presented in section 4.2, to ....

M. A. Orgun, W. W. Wadge, and W. Du. Chronolog(Z): Linear-time logic programming. In O. Abou-Rabia, C. K. Chang, and W. W. Koczkodaj, editors, Proc. of the fifth International Conference on Computing and Information, pages 545--549. IEEE Computer Society Press, 1993.

.... for describing dynamic systems, and have been widely used in many application areas such as program specification and verification [LO97] in modelling temporal databases [Org96] as well as in knowledge representation [LO96] and temporal reasoning [Vil94] However, most temporal languages [Wad88, OM94, Hry93, OWD93, Bau93, Brz91, GRP96] are based on linear flow of time, a fact that makes them unsuitable for certain types of applications. For example, as M. Ben Ari, A. Pnueli and Z. Manna have pointed out in [BAPM83] branching time logics are necessary in order to express certain properties of non deterministic programs. In ....

....of the goal clause. Moreover, program clauses can be directly used in a refutation, without the need to consider their canonical instances. In this sense, CSLD resolution generalizes previously introduced proof procedures for linear time logic languages, such as Chronolog and Chronolog(Z) [Org91, OWD93] as well as for multidimensional logic programming languages [OD94] It is easy to see that CSLD resolution can directly apply to Chronolog programs, which can be seen as programs in Cactus(1) Moreover, CSLD resolution can be easily extended for the case of multidimensional logic programs. The ....

M. A. Orgun, W. W. Wadge, and W. Du. Chronolog(Z): Linear-time logic programming. In O. Abou-Rabia, C. K. Chang, and W. W. Koczkodaj, editors, Proc. of the fifth International Conference on Computing and Information, pages 545--549. IEEE Computer Society Press, 1993.

....Greek General Secretariat of Research and Technology under the project iTimeLogicj of PiENE Delta 0 95, contract no 1134. M. Gergatsoulis, P. Rondogiannis, T. Panayiotopoulos, Disjunctive Chronolog introduced by W. W. Wadge[Wad88] whose semantics have been systematically developed by M. Orgun[Org91, OW92, OWD93]. The proposed formalism, Disjunctive Chronolog, is capable of expressing time related uncertainty of dioeerent forms: Event uncertainty. Consider for example the curriculum of a computer science department, which requires from students to have taken Discrete Mathematics before they register to ....

....of a canonical temporal atom[Org91] A canonical temporal atom is a formula of the form 1 first next n A for some n 0, where A is an atomic formula. A canonical disjunctive temporal clause is a disjunctive temporal clause whose temporal atoms are canonical temporal atoms. As in Chronolog [Org91, OWD93], every disjunctive temporal clause can be transformed into a (possibly in nite) set of canonical disjunctive temporal clauses. This can be done by applying first next n where n 0, to the clause, and then using the axioms of TL to distribute the temporal reference so as to be applied to each ....

M. A. Orgun, W. W. Wadge, and W. Du. Chronolog(Z): Linear-time logic programming. In O. Abou-Rabia, C. K. Chang, and W. W. Koczkodaj, editors, Proc. of the øfth International Conference on Computing and Information, pages 545549. IEEE Computer Society Press, 1993.

.... have been proposed [Org94] A temporal logic programming language that was influenced by the style of Lucid, is Chronolog [Wad88] The theory behind Chronolog is very well understood and developed [Org91, OW92] Many extensions of basic Chronolog have been proposed (to handle integer time [OWD93], to provide multiple dimensions in the style of GLU [OD97] to use choice predicates that support a dataflow style of computations [OW94] to provide branching time [RGP97] to allow uncertainty to be expressed using rules with disjunction in the heads [GRP96] and so on) However, despite its ....

M. A. Orgun, W. W. Wadge, and W. Du. Chronolog(Z): Linear-time logic programming. In O. Abou-Rabia, C. K. Chang, and W. W. Koczkodaj, editors, Proc. of the Fifth International Conference on Computing and Information, pages 545--549. IEEE Computer Society Press, 1993.

....fg. C 0 is a canonical instance of the second program clause, and C 1 is the same as the first clause in the program. Thus we obtain that first next light(Color) is true of the program under the substitution 0 = fColor amberg. Chronolog(Z) is an extension of Chronolog with an unbounded past [78, 80], in which the set of integers Z is the collection of moments in time. The only extra operator in Chronolog(Z) is prev (the previous moment in time) which is the complete inverse of next. It is shown in [78] that TiSLD resolution extended with rules for prev is a sound and complete proof ....

M. A. Orgun, W. W. Wadge, and W. Du. Chronolog(Z): Linear-time logic programming. In Proceedings of ICCI'93: The Fifth International Conference on Computing and Information, Laurentian University, Sudbury, Ontario, Canada, May 27--29 1993. IEEE Computer Society Press.

Online articles have much greater impact   More about CiteSeer.IST   Add search form to your site   Submit documents   Feedback  

CiteSeer.IST - Copyright Penn State and NEC