This work proposes an agent-based system for supporting dynamic scheduling in manufacturing. The ability of dynamic scheduling allows manufacturing production systems to promptly react to on-line demand variations, or in general to unexpected events, as required by the modern "agile" manufacturing paradigm. Multi-agent systems (MASs) have been indicated as a possible enabling factor for agility in manufacturing. This paper considers a class of dynamic scheduling problems characterized by a just-in-time objective and devises an on-line scheduling heuristic based on a multi-agent architecture. An experimental analysis is performed to compare different heuristic configurations with other non-agent-based ones. The results obtained show the effectiveness of the approach.

The aim of this paper is that of defining a protocol for interaction among agents. Such a protocol has been developed within an agent programming framework, including a model of agent and a communication system among agents, implementing that protocol. Moreover a new technological approach is proposed, different with respect to traditional agent programming frameworks which fully exploit benefits coming from object-oriented programming techniques, yet they suffer from some limitations imposed by such an implementation choice. Contrary to the widely adopted use of the Java platform in most agent-based solutions and related research activity, the present work has been entirely carried on in the novel NET framework (Microsoft Corp.) which offers technological solutions able to cope with common problems which often arise when relying on different enterprise platforms (both J2EE and Microsoft DNA). In particular this work strongly benefits from the use of the C# language in the Common Language Infrastructure (CLI).

The aim of this paper is,that of describing the software architecture designed for the implementation of an agent programming framework. Contrary to the widely adopted use of the Java platform. in most agent-based solutions and related research activity, the present work has been entirely carried on in the novel NET framework (Microsoft Corp.) which offers technological solutions able to cope with common problems which often arise when working in other enterprise platforms (both J2EE and Microsoft DNA). In particular this work is based on the C# language and the Common Language Infrastructure. One solution is described to make management of agents easier from a programmer's point of view. As result an agent,programming framework is presented, fully exploiting the above concepts.

In the last decades, a significant growth of agent oriented systems has been observed, which has stimulated a more precise formalism for the definition of both agent and multi-agent systems, as well as the release of a huge number of agent development environment. In this work a new programming paradigm is proposed, that is agent oriented programming instead of object oriented programming. The guidelines for the realization of a suited agent programming language, that is an agent oriented language, can be derived according to the basic characteristics that software agents must have. As well as object oriented programming fully exploits the structured programming basic concepts, agent oriented programming will strongly benefit of both the object oriented model and logic programming theoretical basis. A project for the development of a novel architecture has been presented for software agents’ development in an agent based system that is an Agent Programming Framework based on the Microsoft Common Language Runtime (CLR).

This work concerns the use of multi-agent system models as a paradigm to support dynamic scheduling decisions. A dynamic class of scheduling problems has been considered, and a just-in-time manufacturing production has been assumed. In particular, the problem of scheduling independent jobs on identical parallel machines, to optimise a non-regular objective, including both job earliness and tardiness penalties, has been faced. Different classes of agents compose the multi-agent scheduling system, and a schedule is progressively defined by a negotiation protocol among the agents associated with the jobs and the machines.

The kinetics of global changes in transcription patterns during competence development in Streptococcus pneumoniae was analysed with high-density arrays. Four thousand three hundred and one clones of a S. pneumoniae library, covering almost the entire genome, were amplified by PCR and gridded at high density onto nylon membranes. Competence was induced by the addition of CSP (competence stimulating peptide) to S. pneumoniae cultures grown to the early exponential phase. RNA was extracted from samples at 5 min intervals (for a period of 30 min) after the addition of CSP. Radiolabelled cDNA was generated from isolated total RNA by random priming and the probes were hybridized to identical high-density arrays. Genes whose transcription was induced or repressed during competence were identified. Most of the genes previously known to be competence induced were detected together with several novel genes that all displayed the characteristic transient kinetics of competence-induced genes. Among the newly identified genes many have suggested functions compatible with roles in genetic transformation. Some of them may represent new members of the early or late competence regulons showing competence specific consensus sequences in their promoter regions. Northern experiments and mutational analysis were used to confirm some of the results.