The study aimed to examine the cognitive mechanisms underlying ecstasy consumer’s impaired performance on verbal list learning tasks [1-5]. This was achieved by comparing levels of forgetting across a related and a nonrelated word list. Forgetting a word that was previously recalled once indicated forgetting at level one, forgetting a word that had been recalled twice is forgetting at level 2, ...

Forgetting is an important tool for reducing ontologies by eliminating some concepts and roles while preserving sound and complete reasoning. Attempts have previously been made to address the problem of forgetting in relatively simple description logics (DLs) such as DL-Lite and extended EL . The ontologies used in these attempts were mostly restricted to TBoxes rather than general knowledge ba...

Forgetting irrelevant/problematic actions in a domain description can be useful in solving reasoning problems, such as query answering, planning, conflict resolution, prediction, postdiction, etc.. Motivated by such applications, we study what forgetting is, how forgetting can be done, and for which applications forgetting can be useful and how, in the context of reasoning about actions. We stu...

A novel declarative approach of forgetting in answer set programming (ASP) has been proposed recently. In this paper we report a system prototype of forgetting in ASP, called LPForget. It consists of two modules: (1) Forgetting: computing the result of forgetting about certain literals in logic program under the answer set semantics; (2) CRS: application of forgetting in resolving conflict (or ...

A new semantic forgetting for answer set programs (ASP), called SM-forgetting, is proposed in the paper. It distinguishes itself from the others in that it preserves not only skeptical and credulous consequences on unforgotten variables, but also strong equivalence – forgetting same variables in strongly equivalent logic programs has strongly equivalent results. The forgetting presents a positi...

The result of forgetting some predicates in a first-order sentence may not exist in the sense that it might not be captured by any first-order sentences. This, indeed, severely restricts the usage of forgetting in applications. To address this issue, we propose a notion called k-forgetting, also called bounded forgetting in general, for any fixed number k. We present several equivalent characte...

In this paper we develop a general framework that allows for both knowledge acquisition and forgetting in the Situation Calculus. Based on the Scherl and Levesque (Scherl and Levesque 1993) possible worlds approach to knowledge in the Situation Calculus, we allow for both sensing as well as explicit forgetting actions. This model of forgetting is then compared to existing frameworks. In particu...

In this paper, we propose a semantic forgetting for arbitrary logic programs (or propositional theories) under answer set semantics, called HT-forgetting. The HTforgetting preserves strong equivalence in the sense that strongly equivalent logic programs will remain strongly equivalent after forgetting the same set of atoms. The result of an HT-forgetting is always expressible by a logic program...