Open environments are characterized by their uncertainty and nondeterminism. This poses an inevitable challenge to construction of agents which need to operate in such environments. The agents need to adapt their processing to available resources, deadlines, the goal criteria speci ed by the clients as well their current problem solving context in order to survive. Our research focuses on constructing a framework for robust agent control, using a soft-real time scheduling approach which satis ces all aspects of problem solving. In this paper, we evaluate the performance of our heuristic-based approach using the performance of the policy generated by an optimal controller as the benchmark. Keywords: Selection and Planning, Real-time performance, Designing Agent Systems E ort sponsored by the Defense Advanced Research Projects Agency (DARPA) and Air Force Research Laboratory Air Force Materiel Command, USAF, under agreement number F30602-97-1-0249 and number F30602-99-2-0...

Design-to-Criteria builds custom schedules for agents that meet hard temporal constraints, hard resource constraints, and soft constraints stemming from soft task interactions or soft commitments made with other agents. Design-to-Criteria is designed specifically for online application -- it copes with exponential combinatorics to produce these custom schedules in a resource bounded fashion. This enables agents to respond to changes in problem solving or the environment as they arise. Introduction Complex autonomous agents operating in open, dynamic environments must be able to address deadlines and resource limitations in their problem solving. This is partly due to characteristics of the environment, and partly due to the complexity of the applications typically handled by software agents in our research. In open environments, requests for service can arrive at the local agent at any time, thus making it difficult to fully plan or predict the agent's future workload. In dyn...

. Commitments play a central role in multi-agent coordination. However, they are inherently uncertain and it is important to take these uncertainties into account during planning and scheduling. This paper addresses the problem of handling the uncertainty in commitments. We propose a new model of commitment that incorporates the uncertainty, the use of contingency analysis to reduce the uncertainty, and a negotiation framework for handling commitments with uncertainty. 1 Introduction In a multi-agent system, each agent can only have a partial view of other agents' behavior. Therefore, in order to coordinate the agents' activities, the agents need to have a mechanism to bridge their activities based on the partial knowledge. Commitments has emerged, among many research groups [1--3, 8], as the bridge for multi-agent coordination and planning. By definition, a commitment specifies a pledge to do a certain course of action [9]. A number of commitment semantics have been proposed, for ex...

Real-time control has become increasingly important as technologies are moved from the lab into real world . . .

Design-to-Criteria scheduling is the soft real-time process of custom building a schedule to meet real-time performance goals specified by dynamic client goal criteria (including real-time deadlines). Problem solving tasks are represented using a task model that lays out alternate ways to achieve tasks and subtasks. Recent extensions to this technology has spawned a postscheduling contingency analysis step that can be employed in deadline critical situations where the added computational cost is worth the expense. This is based on the evaluation of available schedules that can be used to recover from a situation in which partially executed schedules cannot be completed successfully. We describe how this analysis improves the schedule evaluation from the uncertainty perspective, and provide empirical evidence to support our claims. 1 Introduction Design-to-Criteria (DTC) scheduling[15] is the soft real-time process of finding an execution path through a hierarchical task ...

Commitments play a central role in multi-agent coordination. However, they are inherently uncertain and it is important to take these uncertainties into account during planning and scheduling. This paper addresses the problem of handling the uncertainty in commitments. We propose a new model of commitment that incorporates the uncertainty, the use of contingency analysis to reduce the uncertainty, and a negotiation framework for handling commitments with uncertainty. Keywords: Multi-agent coordination, Multi-agent planning, Decision making under uncertainty 1 Introduction Handling uncertainty is one of the major topics in artificial intelligence. In a multi-agent system, an agent needs to handle not only the uncertain aspects of its own activities, but also the uncertain perceptions about other agents' behaviors. In this paper we study the uncertainty associated with the commitments among the agents and techniques to reduce the uncertainty. In a multi-agent system, each agent can onl...

Some dynamic supply chain problems are instances of a class of distributed optimization problems that intelligent agents were made to address. Agents are thus a natural enabling technology for such problems. In this paper we describe the use of TÆMS agent technologies on a sterilized dynamic supply chain management problem.

Agent control involves reasoning about local problem solving activities, interacting with other agents, planning for a course of action and contingencies in the event of failure of the action and finally carrying out the actions with limited resources and uncertainty about agent outcomes and the actions of other agents. The growing complexity and dynamics of agents and the environments in which they interact requires robust agent control, where the chance of complete failure of an agent's plan to achieve the high-level goal is minimized. Design-toCriteria is a soft real-time agent control process where schedules are built to meet dynamic client goal criteria (including real-time deadlines) , using a task model that describes alternate ways to achieve tasks and subtasks. In this paper we describe a post-scheduling contingency analysis process that can be employed in deadline critical situations where the added computational cost is worth the expense. We describe the uncertainty represen...