Joint Conference on Declarative Programming

L'Aquila, 6-9 September 1999

Maria Chiara Meo

Background and Motivation

Following Appia-Gulp-Prode'98 in A Coruna (Spain) the last joint Appia-Gulp-Prode Conference was held in L'Aquila (Italy), on September 6-9, 1999.

The Conference was organized by the Department of Pure and Applied Mathematics of the University of L'Aquila and Gulp. Compulog-Net, the University of L'Aquila, the Fondazione Cassa di Risparmio di L'Aquila and the MURST 40% Project "Tecniche formali per la specifica, l'analisi, la verifica, la sintesi e la trasformazione di sistemi software" granted financial support to the organization of the Conference.

The technical programme of the Conference included 40 communications. All the papers were evaluated by at least two referees. The programme also included three invited lectures given by Remo Pareschi (Telecom Italia, Italy), Paul Tarau (U. North Texas, USA) and Mirek Truszczynski (U. of Kentucky, USA) as well as two tutorials given by Michele Bugliesi (U. Venezia, Italy) and Alberto Policriti (U. Udine). We thank them all for accepting our invitation. There were 60 participants representing 6 countries, speakers and tutorialists included. The aim of the Conference is to favour scientific excahnges amongst Italian, Portuguese and Spanish researchers, to show recent applications of declarative programming (through the invited talks), to enlighten the interactions between declarative programming and other areas of computer science (through the tutorials) and to discuss ongoing research on the many aspects of declarative programming (through the technical contributions).

The invited talks

Remo Pareschi presented a Work Force Management System developed at CSELT, called RAPID, which has a core part made of about 4 million code lines and makes extensive use of constraint propagation techniques in its scheduling module called ARCO. ARCO is capable of solving the task of dispatching activities to technicians in nearly constant time by narrowing the search space, by stopping after the first reasonable solution, and by heavily applying search heuristics. Thus, the optimal solution is not guaranteed, but the search process goes in any case much deeper than the search capabilities of a human supervisor.


Paul Tarau introduced a set of reusable design patterns and programming techniques for multi-threaded logic programming languages. He described some typical patterns for building reusable components, and showed how complexities of networking are incapsulated as mobile code. Finally, he presented (and demonstrate) components built in a declarative style with multi-threaded BinProlog and Jinni, exhibiting reusable patterns for distributed programming, event-driven visual programming and knowledge exchange protocols for cooperative agent systems.


Mirek Truszczynski reexamined the place and role of stable model semantics programming and contrasted it with a least Herband model approach to Horn programs. He demonstrated that the inherent features of stable model semantics naturally lead to a logic programming paradigm, called answer set programming, that offers an interesting alternative to more traditional logic programming. Finally he discussed recent advances in implementations of computational systems for answer set programming and discussed their performance.


The tutorials

Michele Bugliesi presented the main concepts and ideas behind the object calculi and their type systems, then he described existing work on functional interpretations. Moreover he reviewed recent proposals for logic interpretations of objects in linear logic languages.


Alberto Policriti described and discussed some of the main formalisms and instruments adopted to specify and reason about time in various context. To this end he presented some of the most popular temporal logics and some relationship between game theory and temporal logics.


The technical contributions

The technical contributions covered a wide range of topics, such as Theory and Foundations, Program Analysis, Program Transformation, Agent Systems, Functional and Logic Languages, Databases, Theorem Proving, Automated Reasoning, Constraints, Extensions and Implementations, Applications, Meta and Higher-order.

The conference venue and social events

The Conference was held in the Aula Magna "V. Rivera" of the University of L'Aquila, in the center of the town.

On Tuesday evening the participants were taken a guided tour of the Castello Cinquecentesco. This magnific fortress was built during the Spanish domination (16th century) and today is the site of the National Museum of Abruzzo.

On Wednesday afternoon the participants visited the Basilica of Santa Maria di Collemaggio, one of the main monuments of L'Aquila, with its splendid romanesque-gotic architecture. Afterwards an excursion was organized to the villages of Santa Maria di Bazzano and Bominaco and finally to the Grotte di Stiffe. A subterranean river, which originates from several natural sinks of the above karst-tableland, flows through the caves. Walking up along the river, one enjoys the sight of various small lakes, rapids and water-falls, which rise 20 meters high and whose flow varies according to the seasons, making an ever-changing underground landscape.

The social banquet was held in an old monastery, located in the village of Sirente. The excursion and the social banquet were appreciated very much by all the participants.

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