The CURRENT Platform: Building Conversational Agents in Oz

  • Torbjörn Lager
  • Fredrik Kronlid
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3389)


At the GU Dialogue Systems Lab in Göteborg we are embedding a conversational agent platform – the Current platform – in the Oz programming language. Current is based on a simple and intuitive characterization of conversational agents as interactive transducers, and on the fact that this characterization has a very direct implementation in Oz. Concurrency as offered by Oz allows our agents to ‘perceive’, ‘think’ and ‘act’ at the same time. Concurrency in combination with streams allow our agents to process input in an incremental manner, even when the original underlying algorithms are batch-oriented. Concurrency and streams in combination with ports allow us to specify the ‘toplevel’ transducer as a network of components – an interesting and highly modular architecture. We believe that software tools for specifying networks should have a strong visual aspect, and we have developed a ‘visual programming language’ and an IDE to support it. Also, we have found that if we specify the non-visual aspects of transducers and other components as class definitions that inherit the methods responsible for the interpretation of condition-action rules, regular expressions, grammars, dialogue management scripts, etc. from (abstract) classes provided by separate modules, we are able to hide most of the gory details involving threads, streams and ports from the agent developer.


Regular Expression Parse Tree Input Stream Output Stream Conversational Agent 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Torbjörn Lager
    • 1
  • Fredrik Kronlid
    • 1
  1. 1.Department of LinguisticsGU Dialogue Systems Laboratory, Göteborg University 

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