Back to first pageBack to first page Centre for Artificial Intelligence of UNL
Browse our site
You are here:

Publication details

Go back
Publication details
Main information
Layered Models Top-Down Querying of Normal Logic Programs
January 2009
LMs
Use of top-down query-driven proof procedures is essential for an efficient use and computation of answers using Logic Programs as KBs. Current standard 2-valued semantics for Normal Logic Programs (NLPs), Stable Models (SMs), does not allow top-down query-solving because it does not enjoy the relevance property, and moreover does not guarantee existence of a model for every NLP. To overcome these limitations we introduce a 2-valued semantics for NLPs—Layered Models (LM)— that conservatively extends the SMs, enjoys relevance and guarantees model existence. Moreover, for existential query answering there is no need to compute total models, but just the partial models that sustain the answer to the query. A first implementation of a query-solving engine based on LM is presented. It uses the XSB-Prolog engine and its XASP interface to Smodels, providing a useful tool built as a hybrid of the two systems, taking advantage of the best of each.
In proceedings
Luís Moniz Pereira, Alexandre Miguel Pinto
Proceedings of the Practical Aspects of Declarative Languages (PADL'09)
LNCS
Springer
-
-
-
-
-
-
http://centria.di.fct.unl.pt/~lmp/publications/online-papers/LMTDQ.pdf
Publication files
- click here to download - pdf 862 KB
Export formats
Luís Moniz Pereira and Alexandre Miguel Pinto, Layered Models Top-Down Querying of Normal Logic Programs, , Proceedings of the Practical Aspects of Declarative Languages (PADL'09), LNCS, Springer, (http://centria.di.fct.unl.pt/~lmp/publications/online-papers/LMTDQ.pdf), January 2009.
<a href="/people/members/view.php?code=6175f826202ff877fba2ad77784cb9cb" class="author">Luís Moniz Pereira</a> and <a href="/people/members/view.php?code=76dee43781430d064f62dee3fbdf47a8" class="author">Alexandre Miguel Pinto</a>, <b>Layered Models Top-Down Querying of Normal Logic Programs</b>, <u>Proceedings of the Practical Aspects of Declarative Languages (PADL'09)</u>, LNCS, <a href="http://www.springer.com" title="Link to external entity..." target="_blank" class="publisher">Springer</a>, (<a href="http://centria.di.fct.unl.pt/~lmp/publications/online-papers/LMTDQ.pdf" target="_blank">url</a>), January 2009.
@inproceedings {LMs, author = {Lu\'{\i}s Moniz Pereira and Alexandre Miguel Pinto}, title = {Layered Models Top-Down Querying of Normal Logic Programs}, booktitle = {Proceedings of the Practical Aspects of Declarative Languages (PADL'09)}, series = {LNCS}, publisher = {Springer}, url = {http://centria.di.fct.unl.pt/~lmp/publications/online-papers/LMTDQ.pdf}, abstract = {Use of top-down query-driven proof procedures is essential for an efficient use and computation of answers using Logic Programs as KBs. Current standard 2-valued semantics for Normal Logic Programs (NLPs), Stable Models (SMs), does not allow top-down query-solving because it does not enjoy the relevance property, and moreover does not guarantee existence of a model for every NLP. To overcome these limitations we introduce a 2-valued semantics for NLPs—Layered Models (LM)— that conservatively extends the SMs, enjoys relevance and guarantees model existence. Moreover, for existential query answering there is no need to compute total models, but just the partial models that sustain the answer to the query. A first implementation of a query-solving engine based on LM is presented. It uses the XSB-Prolog engine and its XASP interface to Smodels, providing a useful tool built as a hybrid of the two systems, taking advantage of the best of each.}, month = {January}, year = {2009}, }
Publication's urls
/publications/view.php?code=b7a39f681228d1d218158cd9fa8cc4b1
/publications/view.php?code=LMs
Go back
Centre for Artificial Intelligence of UNL
Departamento de Informática, FCT/UNL
Quinta da Torre 2829-516 CAPARICA - Portugal
Tel. (+351) 21 294 8536 FAX (+351) 21 294 8541

Fundacao_FCT