A norm-regulated Deontic Action-Logic Multi-Agent System (DALMAS) is regulated by a normative system consisting of norms, which are expressed in an algebraic notation based on the Kanger-Lindahl theory of normative positions. A general-level Prolog implementation of the abstract DALMAS architecture makes it possible to implement specific systems in Prolog. This work describes jDALMAS, a Java library that may be used to create DALMAS applications in Java. A jDALMAS application has a client/server architecture, where a Prolog implementation of a specific system acts as a logic server. Together, the general-level Prolog implementation and the jDALMAS packages offer a framework for implementation of specific systems. Two examples of such implementations are presented here.

Many multi-agent systems (MAS) and other kinds of dynamic systems may be modeled as transition systems, in which actions are associated with transitions between different system states. This paper presents an approach to normative systems in this context, in which the permission or prohibition of actions is related to the permission or prohibition of different types of state transitions with respect to some condition d on a number of agents x₁, ... , x_n in a state. It introduces the notion of a norm-regulated transition system situation, which is intended to represent a single step in the run of a (norm-regulated) transition system. The normative framework uses an algebraic representation of conditional norms and is based on a systematic exploration of the possible types of state transitions with respect to d(x₁, ... , x_n). A general-level Java/Prolog framework for norm-regulated transition system situations is currently being developed.

An approach to normative systems in the context of multiagent systems (MAS) modeled as transition systems, in which actions are associated with transitions between different system states, is presented. The approach is based on relating the permission or prohibition of actions to the permission or prohibition of different types of state transitions with respect to some condition d on a number of agents x(1), ... , x(nu) in a state. It introduces the notion of a norm-regulated transition system situation, which is intended to represent a single step in the run of a (norm-regulated) transition system. The normative framework uses an algebraic representation of conditional norms and is based on a systematic exploration of the possible types of state transitions with respect to d(x(1), ... , x(nu)). A general-level Java/Prolog framework for norm-regulated transition system situations has been developed, and this implementation together with a simple example system is presented and discussed.

The Kanger-Lindahl theory of normative positions has great potential of serving as a logical foundation for normative systems for MAS, and its generality allows for great freedom when interpreting the theory. As a first step towards a typology of interpretations of the theory, we study the application of normative positions in the context of a class of transition systems in which transitions are deterministic and associated with a single agent performing an act. By an interpretation of different types of normative positions in terms of permitting or prohibiting different state transition types in this context, lexicons for two different systems of types of normative positions are suggested and discussed. It is demonstrated that both interpretations areuseful foundations for normative systems semantics in a MAS context.

An approach to the pre-runtime design of normative systems for a class of problem-solving norm-regulated multi-agent systems is suggested. The basic idea is to employ evolutionary mechanisms to evolve efficient normative systems for so-called norm-regulated Dalmases, as part of the design process. The Dalmas architecture uses an algebraic approach to normative systems, in which normative consequences are based on an extended set of one-agent types of normative positions, which is given a semantics in terms of prohibition of certain types of state transitions. To illustrate the approach, a genetic algorithm is used to evolve norms for an example system. Furthermore, some approaches to reducing the algorithm’'s search space, including to employ a notion of ‘operational equivalence’ of norms, are discussed. It is demonstrated that an evolutionary algorithm may be a useful tool when designing norms for problem-solving multi-agent systems.