H. A##t-Kaci and R. Nasr. LOGIN: A logic programming language with built-in inheritance. Journal of Logic Programming, 3:185#215, 1986.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....of the knowledge base. Third,the resulting system provides a form of integration between objects and logic within the framework of databases. Recently, there has been muchinterest in investigating database systems providing both deductive and object oriented capabilities, see for example #A##t Kaci and Nasr, 1986, Abiteboul and Kanellakis, 1989, Abiteboul, 1990,Kifer et al., 1995,Ling et al., 1995#. Compared with most of the proposals of this kind,AL log is more expressive in the structural component, and provides more sophisticated reasoning mechanisms on such component. Indeed, one of the main features ....

H. A##t-Kaci and R. Nasr. LOGIN: A logic programming language with built-in inheritance. Journal of Logic Programming, 3:185#215, 1986.

.... Shapiro, 1986] Examples of such languages are G odel a language which provides, among others, special language facilities for better control over reasoning [Hill Lloyd, 1994] and Login and Life which are Prolog like languages with built in inheritance relationships among terms [A t Kaci Nasser, 1986; A t Kaci Podelski, 1993] New programming paradigms have also been introduced in the realm of logic programming, such as logic object oriented programming in the language L O, McCabe, 1992] which allows programs to be organized into classes, and to reason over expressed relationships ....

At-Kaci, H and Nasser, R, 1986. \LOGIN: A logic programming language with built-in inheritance", J. Logic Programming 3 185-215.

....17] We go one step further and employ feature terms, instances of record like types organized in a subsumption based taxonomy. The unification of feature terms restricts the terms to their greatest common subtype, and their features to the corresponding subtypes specified in the type definition ([1, 5, 13, 16, 18, 19, 21, 25], cf [14] for a discussion of PROLOG based implementations of conceptual graphs) We note that feature term unification is equally well suited to enforce grammatical agreement rules and the subsumption principles of concepts systems. Rewritten, the grammar could have the following form: types ....

....or meaning, however, is represented in a different form. According to the notation of conceptual structures [20] the de facto standard for medical concept representation, the content of sentence (1) could be represented by: uptake] existence) certain] form) area] occurrences) [1], quantification) increased] location) lumbosacral junction] relative position) at] Dependency Parsing for Medical Language and Concept Representation 24.04.97 (side) right] which is the textual equivalent of Fig. 1b. It corresponds to the following dependency tree: ....

H. Aït-Kaci and R. Nasr, LOGIN: A logic programming language with built-in inheritance, The Journal of Logic Programming 3 (1986) 186--215.

....natural language [25, 27, 49] In programming languages, attribute value combinations are used in record structures. A t Kaci was the first to study such structures mathematically, calling them # terms [2] The resulting # term calculus is the formal foundation of the programming languages LOGIN [3] and LIFE [4] which are similar to PROLOG, but use feature unification [51] instead of syntactic unification. In contrast to several description logics, attributes in # terms are functional : they can have only one value. This is convenient, since objects can be identified by some unique ....

Aït-Kaci, H., and Nasr, R. Login: A logic programming language with built-in inheritance. Journal of Logic Programming 1986, 3 (1986), 186--215.

....for subtype supertype (i.e. isa) relation, ordersorted logics have been developed (for overview, see [Obe89] In those, a partial ordering on sorts is assumed which basically is a subsort supersort relation. A good example of an order sorted logic programming language is EPOS [HV87] The LOGIN [AN86] language (which served as a starting point for the ALF [Mel88] merger of OO and logic) can also be regarded as relying on a variant of order sorted logic (feature types) its peculiarity being that there are no sorts there, and individuals are ordered instead. The ordering itself, thereby, is ....

H. Aït-Kaci and R. Nasr. LOGIN: A logic programming language with built-in inheritance. J. Logic Programming, 3(3):185-215, 1986.

....for convenient database access, depending on one s point of view. Since Congress is implemented as a library of classes, any C program can use Congress as a higher level alternative to or enhancement of the raw C term interface. As a logic programming language, Congress is a dialect of LOGIN [1], an extension of Prolog that supports cyclic terms. It provides transparent persistence, and has an identity based rather than valuebased semantics. The following paragraphs briefly describe the syntax and semantics of Congress. The reader who is familiar with logic programming may skim this ....

....original call succeeds, or until all alternatives have been exhausted, in which case it fails . Adams and Solomon CAPITL Page 5 The heart of this process is the definition of matching between terms, called unification. 3 Congress uses a variant of unification that supports cyclic terms [1]. The goal of unification is to determine if two terms are isomorphic, or can be made isomorphic by substituting terms for variables. Two terms unify if their roots match (have the same functor) and corresponding successors (recursively) unify. That is, if both roots have arcs with the same ....

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H. At-Kaci and R. Nasr, LOGIN: A Logic Programming Language with Built-In Inheritance, Journal of Logic Programming, Mar. 1986, 181-215.

....CCP or KAP mentioned at the beginning of this section. The indepence property means among other things that negative constraints can essentially be handled through entailment simplification. One origin of FT is At Kaci s term calculus [1] which is at the heart of the programming language LOGIN [2] and further extended in the language LIFE [4] with functions over feature structures thanks to a generalization of the concept of residuation of Le Fun [3] Other precursors of FT are the feature descriptions found in so called unification grammars [12, 11] developed for natural language ....

H. At-Kaci and R. Nasr. LOGIN:A logic programming language with built-in inheritance. The Journal of Logic Programming, 3:185--215, 1986.

.... root are the unification grammar formalisms FUG [21] and LFG [20] developed for applications in computational linguistics (see [11] for a more recent paper in this area) Another, independent root is Ait Kaci s term calculus [1, 2] which is the basis of several constraint programming languages [4, 5, 6]. Smolka [29] gives a unified logical view of most earlier feature formalisms and studies an expressive feature constraint logic. Feature trees appeared only recently with the work on FT [9, 7] To our knowledge the notion of an arity constraint is new. Carpenter s [11] extensional types are ....

.... The resulting constraint system CFT is a conservative extension of both Prolog II s rational tree system [12, 13] and the feature tree system FT [9, 7] Thus CFT brings together the work on classical tree constraints (e.g. 17, 12, 13, 23, 26] and the work on feature descriptions (e.g. [21, 20, 1, 2, 4, 5, 6, 29, 9, 7, 11]) two lines of research that seemed to be rather far apart in the past. The declarative semantics of CFT was specified both algebraicly (the feature tree structure T ) and logically (the first order theory CFT given by five axiom schemes) For the constraint problems considered in the paper the ....

H. Ait-Kaci and R. Nasr. LOGIN: A logic programming language with built-in inheritance. Journal of Logic Programming, 3:185--215, 1986.

....that the long denied need to manipulate structured data is currently and fashionably finding some satisfaction in object oriented databases which lack valuable RDBMS properties such as referential transparency, declarativity, optimisability etc. Data abstraction and inheritance are not at odds [AitK86] with the logic programming concepts with which we propose to generalise the relational model. 3.6 Recursive queries In the history of PL development, recursive procedure execution was originally regarded as an abstruse feature of purely academic interest, unnecessary and inefficient in ....

H. Ait-Kaci and R. Nasr, "LOGIN: A Logic Programming Language with Builtin Inheritance", J. Logic Programming, vol. 3, no. 3, pp. 185-215 (1986).

....is used in this paper is new but similar data models exist in the literature. In particular, the notions of alternation and construction appear as classification and aggregation in both Hull and Yap s Format Model [HY84] and Kuper and Vardi s LDM [KV84] Ait Kaci s feature structures [AKN86] are also related to the Demeter kernel model. Our abstraction algorithms can be adapted to abstract feature structures from examples (this was actually the starting point of our investigation) Other related work in the data base field is described in: AH88, BMW86, TL82] Winston s work [Win70] ....

H. Ait-Kaci and R. Nasr. Login: A logic programming language with built-in inheritance. Journal of Logic Programming, 3:185--215, 1986.

....into account the so called concept description logics, also known as terminological logics, that are abstractions for several languages in Computer Science and Artificial Intelligence. The importance of concept languages in data modeling [7] object oriented data bases [3] and logic programming [1] has been stressed by several authors. The computational complexity of concept languages has been extensively studied by many researchers (see [24, 26, 58, 67] In particular, it has been shown that reasoning is polynomially intractable in many interesting cases, and that tractability depends on ....

H. Ait-Kaci and R. Nasr. Login: a logic programming language with built-in inheritance. Journal of Logic Programming, 3:185--215, 1986.

....Properties The organization of large bodies of knowledge, with complex relationships and interdependencies among its components, has been the target of both artificial intelligence and database research. The particular results that contributed to the ideas in this thesis are the work of A it Kaci [1] and its formalization in order sorted equational logic by Smolka and A it Kaci [47] 22 A it Kaci introduced the notion of inheritance hierarchies built up from feature types. Feature types are ordered by subtyping and the elements of a feature type are records. The features of a feature type ....

....are relevant similarities as well. The original terms introduced by A it Kaci ( Gammaterms) were conceived as organizing and defining inheritance hierarchies that represented the subset structure of information. The hierarchy could then be incorporated into a logic query language such as LOGIN [1]. The information in these kinds of hierarchies is typically set descriptions, such as the description of a set of students by describing the characteristics of what is a student; the description of the set of parttime students similarly (a subset of students) the description of the set of ....

A it-Kaci, H., and Nasr, R. LOGIN: A logic-programming language with built-in inheritance. Journal of Logic Programming 3 (1986), 185--215.

....Vol. 16, No. 4, July, 1994, Pages 1 40. Functions as Passive Constraints in LIFE Delta 3 [At Kaci and Nasr 1989] This simple idea turns out invaluable in practice. Here are a few benefits. Such nondeclarative heresies as the is predicate in Prolog and the freeze metapredicate in some of its extensions [Colmerauer 1982b; Naish 1986] are not needed. Functional computations are determinate and do not incur the overhead of the search strategy needed by logic programming. Higher order functions are easy to return or pass as arguments since functional variables can be bound to partially applied functions. Functions can ....

A it-Kaci, H. and Nasr, R. 1986. LOGIN: A logic programming language with built-in inheritance.

....and ML. This gives the more flexible feature trees an interesting potential. More precisely, feature trees model extensible record structures. They form the semantics of record calculi like [1] which are used in symbolic programming languages [5] and in computational linguistics (for example, see [3, 24] and the book [8] Generally, these extensible record structures allow hierarchical representation of partial knowledge. They lend themselves to object oriented programming techniques [3] Let us suppose that we want to say that x is a wine whose grape is riesling and whose color is white. To do ....

....which are used in symbolic programming languages [5] and in computational linguistics (for example, see [3, 24] and the book [8] Generally, these extensible record structures allow hierarchical representation of partial knowledge. They lend themselves to object oriented programming techniques [3]. Let us suppose that we want to say that x is a wine whose grape is riesling and whose color is white. To do this in Herbrand, one may write the equation: x = wine(riesling; white; y 1 ; y n ) with the implicit assumption that the first argument of the constructor wine carries the ....

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H. At-Kaci and R. Nasr. LOGIN:A logic programminglanguage with built-in inheritance. The Journal of Logic Programming, 3:185--215, 1986.

....and ML. This gives the more flexible feature trees an interesting potential. More precisely, feature trees model extensible record structures. They form the semantics of record calculi like [1] which are used in symbolic programming languages [5] and in computational linguistics (for example, see [3, 24] and the book [8] Generally, these extensible record structures allow hierarchical representation of partial knowledge. They lend themselves to object oriented programming techniques [3] Let us suppose that we want to say that x is a wine whose grape is riesling and whose color is white. To do ....

....which are used in symbolic programming languages [5] and in computational linguistics (for example, see [3, 24] and the book [8] Generally, these extensible record structures allow hierarchical representation of partial knowledge. They lend themselves to object oriented programming techniques [3]. Let us suppose that we want to say that x is a wine whose grape is riesling and whose color is white. To do this in Herbrand, one may write the equation: x = wine(riesling; white; y 1 ; y n ) with the implicit assumption that the first argument of the constructor wine carries the ....

[Article contains additional citation context not shown here]

H. At-Kaci and R. Nasr. LOGIN: A logic programming language with built-in inheritance. The Journal of Logic Programming, 3:185--215, 1986.

....to tailor programming languages, typically logic programming, for linguistic analysis. As has been pointed out in [12] order sorted logic is quite convenient for parsing. Among those known to us CIL [17, 18] is one that comes close to LIFE s spirit in that it combines partial features of Log In [3] (see Section 2.2.2) with delayed evaluation handled with an explicit freeze meta predicate borrowed from Prolog II [11] CIL s constructs are called Partially Specified Terms (PST s) which are exactly the same as feature matrices used in Unification Grammars [23] and are a strict particular case ....

....to logic programming is the presence of first order constructor terms as well as unification. 2.1.3 Calculus: Computing with Types The calculus consists of a syntax of structured types called terms together with subtyping and type intersection operations. Intuitively, as expounded in [3], the calculus is an attempt at obtaining a convenience for representing record like data structures in logic and functional programming more adequate than first order terms without loss of the well appreciated instantiation ordering and unification operation. The natural interpretation of a ....

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At-Kaci, H. and Nasr, R., "LOGIN: A Logic Programming Language with Built-in Inheritance." Journal of Logic Programming 3(3), pp. 187--215. 1986.

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H. At-Kaci & R. Nasr, "LOGIN: A Logic Programming Language with Built-in Inheritance," Journal of Logic Programming 1986, 185--215.

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H. Ait-Kaci and R. Nasr. Login: A logic programming language with built-in inheritance. Journal of Logic Programming, 3:185--215, 1986.

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