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Sandra Sandri - One of the best experts on this subject based on the ideXlab platform.

  • on the semantics and automated deduction for plfc a logic of possibilistic uncertainty and fuzziness
    arXiv: Artificial Intelligence, 2013
    Co-Authors: Teresa Alsinet, Lluis Godo, Sandra Sandri
    Abstract:

    Possibilistic logic is a well-known graded logic of uncertainty suitable to reason under incomplete information and partially inconsistent knowledge, which is built upon classical first order logic. There exists for Possibilistic logic a proof procedure based on a refutation complete Resolution-style calculus. Recently, a syntactical extension of first order Possibilistic logic (called PLFC) dealing with fuzzy constants and fuzzily restricted quantifiers has been proposed. Our aim is to present Steps towards both the formalization of PLFC itself and an automated deduction system for it by (i) providing a formal semantics; (ii) defining a sound Resolution-style calculus by refutation; and (iii) describing a first-order proof procedure for PLFC clauses based on (ii) and on a novel notion of most general substitution of two literals in a Resolution Step. In contrast to standard Possibilistic logic semantics, truth-evaluation of formulas with fuzzy constants are many-valued instead of boolean, and consequently an extended notion of possibilistic uncertainty is also needed.

  • on the semantics and automated deduction for plfc a logic of possibilistic uncertainty and fuzziness
    Uncertainty in Artificial Intelligence, 1999
    Co-Authors: Teresa Alsinet, Lluis Godo, Sandra Sandri
    Abstract:

    inconsistent Recently, a syntactical extension of first order Possibilistic logic (called PLFC) dealing with fuzzy constants and fuzzily restricted quantifiers has been proposed. In this paper we present Steps towards both the formalization of PLFC itself and an automated deduction system for it by (i) providing a formal semantics; (ii) defining a sound Resolution-style calculus by refutation; and (iii) describing a first-order proof procedure for PLFC clauses based on (ii) and on a novel notion of most general substitution of two literals in a Resolution Step.

Teresa Alsinet - One of the best experts on this subject based on the ideXlab platform.

  • on the semantics and automated deduction for plfc a logic of possibilistic uncertainty and fuzziness
    arXiv: Artificial Intelligence, 2013
    Co-Authors: Teresa Alsinet, Lluis Godo, Sandra Sandri
    Abstract:

    Possibilistic logic is a well-known graded logic of uncertainty suitable to reason under incomplete information and partially inconsistent knowledge, which is built upon classical first order logic. There exists for Possibilistic logic a proof procedure based on a refutation complete Resolution-style calculus. Recently, a syntactical extension of first order Possibilistic logic (called PLFC) dealing with fuzzy constants and fuzzily restricted quantifiers has been proposed. Our aim is to present Steps towards both the formalization of PLFC itself and an automated deduction system for it by (i) providing a formal semantics; (ii) defining a sound Resolution-style calculus by refutation; and (iii) describing a first-order proof procedure for PLFC clauses based on (ii) and on a novel notion of most general substitution of two literals in a Resolution Step. In contrast to standard Possibilistic logic semantics, truth-evaluation of formulas with fuzzy constants are many-valued instead of boolean, and consequently an extended notion of possibilistic uncertainty is also needed.

  • on the semantics and automated deduction for plfc a logic of possibilistic uncertainty and fuzziness
    Uncertainty in Artificial Intelligence, 1999
    Co-Authors: Teresa Alsinet, Lluis Godo, Sandra Sandri
    Abstract:

    inconsistent Recently, a syntactical extension of first order Possibilistic logic (called PLFC) dealing with fuzzy constants and fuzzily restricted quantifiers has been proposed. In this paper we present Steps towards both the formalization of PLFC itself and an automated deduction system for it by (i) providing a formal semantics; (ii) defining a sound Resolution-style calculus by refutation; and (iii) describing a first-order proof procedure for PLFC clauses based on (ii) and on a novel notion of most general substitution of two literals in a Resolution Step.

Lluis Godo - One of the best experts on this subject based on the ideXlab platform.

  • on the semantics and automated deduction for plfc a logic of possibilistic uncertainty and fuzziness
    arXiv: Artificial Intelligence, 2013
    Co-Authors: Teresa Alsinet, Lluis Godo, Sandra Sandri
    Abstract:

    Possibilistic logic is a well-known graded logic of uncertainty suitable to reason under incomplete information and partially inconsistent knowledge, which is built upon classical first order logic. There exists for Possibilistic logic a proof procedure based on a refutation complete Resolution-style calculus. Recently, a syntactical extension of first order Possibilistic logic (called PLFC) dealing with fuzzy constants and fuzzily restricted quantifiers has been proposed. Our aim is to present Steps towards both the formalization of PLFC itself and an automated deduction system for it by (i) providing a formal semantics; (ii) defining a sound Resolution-style calculus by refutation; and (iii) describing a first-order proof procedure for PLFC clauses based on (ii) and on a novel notion of most general substitution of two literals in a Resolution Step. In contrast to standard Possibilistic logic semantics, truth-evaluation of formulas with fuzzy constants are many-valued instead of boolean, and consequently an extended notion of possibilistic uncertainty is also needed.

  • on the semantics and automated deduction for plfc a logic of possibilistic uncertainty and fuzziness
    Uncertainty in Artificial Intelligence, 1999
    Co-Authors: Teresa Alsinet, Lluis Godo, Sandra Sandri
    Abstract:

    inconsistent Recently, a syntactical extension of first order Possibilistic logic (called PLFC) dealing with fuzzy constants and fuzzily restricted quantifiers has been proposed. In this paper we present Steps towards both the formalization of PLFC itself and an automated deduction system for it by (i) providing a formal semantics; (ii) defining a sound Resolution-style calculus by refutation; and (iii) describing a first-order proof procedure for PLFC clauses based on (ii) and on a novel notion of most general substitution of two literals in a Resolution Step.

Jacques Cohen - One of the best experts on this subject based on the ideXlab platform.

  • logic programming and constraint logic programming
    ACM Computing Surveys, 1996
    Co-Authors: Jacques Cohen
    Abstract:

    Logic programming is a language paradigm based on logic, more specifically on Resolution theorem proving in the predicate calculus as proposed in Robinson [1965]. Robinson had the foresight to distinguish the importance of two components in automatic theorem proving: a single inference rule called Resolution and the testing for equality of trees called unification. Resolution is an inference Step used to prove the validity of predicate calculus formulas expressed as clauses. In its simplest version: P ~ Q and -P ~ R imply Q ~ R, which is called the resolvant. Unification is the matching of terms used in a Resolution Step. It consists of testing the satisfiability of the equality of terms (i.e., labeled trees) whose leaves may contain variables. For example, the unification of the terms p(X, q(Z, a)) and p(b, q(a, Y)) succeeds, yielding the bindings X 5 b, Z 5 a, and Y 5 a. Prolog, the main representative of LP, consists of a sequence of Horn clauses. A Horn clause is one containing (at most) one positive literal. The term definite clause is used to denote a clause with exactly one positive literal. Prolog programs can be viewed as a set of definite clauses in which the positive literal is the head of the rule and the negative literals constitute the body or tail of the rule. From a procedural point of view, a head corresponds to the definition of a Boolean function whose body consists of conjunctions of calls to the Boolean functions representing the tail [Kowalski 1979]. A quintessential example of a Prolog program is that of append. It consists of two Horn clauses specifying that list L3 is the concatenation of two lists, L1 and L2:

Stefano Curti - One of the best experts on this subject based on the ideXlab platform.

  • synthesis of the nk1 receptor antagonist gw597599 part 1 development of a scalable route to a key chirally pure arylpiperazine
    Organic Process Research & Development, 2008
    Co-Authors: Giuseppe Guercio, Sergio Bacchi, Michael Goodyear, Antonella Carangio, Francesco Tinazzi, Stefano Curti
    Abstract:

    GW597599 1 is a novel NK-1 antagonist currently under investigation for the treatment of CNS disorders and emesis. The initial synthetic route devised from the medicinal chemistry one, used several hazardous reagents, gave low yields, and produced high levels of wastes. By targeted process of research and development, application of novel techniques, and extensive route scouting, a novel synthetic route for GW597599 has been developed. This paper reports the optimisation work of the first stage in the chemical synthesis of GW597599: the development of a pilot-plant suitable process for the synthesis of the arylpiperazine derivative 7 in an optically pure fashion. In particular, the process definition allowed eliminating the initial need for cryogenic conditions and copper catalysis in Grignard chemistry. It also allowed replacing a classical Resolution Step with a more efficient dynamic kinetic Resolution, substantially enhancing the overall yield and throughput.