Marco M. Carvalho

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To increase the assurance with which agents can be deployed in operational settings, we have been developing the KAoS policy and domain services. In conjunction with Nomads strong mobility and safe execution features, KAoS services and tools allow for the specification, management, conflict resolution, and enforcement of DAML-based policies within the(More)
Information visualization has been a research topic for many years, leading to a mature field where guidelines and practices are well established. Knowledge visualization, in contrast, is a relatively new area of research that has received more attention recently due to the interest from the business community in Knowledge Management. In this paper we(More)
The sociotechnical workplace is constantly changing, and constant change in environmental constraints may require constant adaptation in cognitive work, even if domain constraints remain constant. This rule is a consequence of the bounded ecology of macrocognitive work systems. 2 A work system can never match its environment completely; there are always(More)
Electronic concept mapping tools empower experts to play an active role in the knowledge capture process, and provide a medium for building richly connected multimedia <i>knowledge models---</i>sets of linked concept maps and resources about a particular domain. Knowledge models are intended to be used as a means for sharing knowledge among humans, not as(More)
Safety and efficiency are primary concerns in chemical processing facilities, though the complexity of many such systems often makes it difficult for operators to detect abnormal conditions before they compromise throughput or become hazardous. In this paper, we report initial results from the application of multi-agent systems to monitor complex chemical(More)
This paper describes an approach to runtime policy-based control over information exchange that allows a far more fine-grained control of these dynamically discovered agent interactions. The DARPA Agent Markup Language (DAML) is used to represent policies that may either filter messages based on their semantic content or transform the messages to make them(More)
This paper introduces the use of mobile agents as the mechanism for policy enforcement in multi-agent multi-domain systems. The focus is on the effective application of communication policies in the setup and maintenance of spanning data streams that cross multiple hosts in different domains. We have designed and implemented a mobile agent based framework(More)
Growing recognition of the benefits of mobile agents in distributed systems, such as military C4ISR, has led to a proliferation of mobile agent systems. However, incompatibilities between proprietary systems prevent the greater potential benefits of ubiquitous mobile agent computing. In particular, agents cannot migrate to a host that runs a different(More)
The construction of a concept map consists of enumerating a list of concepts and —a more difficult task— determining the linking phrases that should connect the concepts to form meaningful propositions. Appropriate word selection, both for concepts and linking phrases, is key for an accurate knowledge representation of the user's understanding of the(More)