13990575
A Methodology and Modelling Technique for Systems of BDI Agents
The construction of large-scale embedded software systems demands the use of design methodologies and modelling techniques that support abstraction, inheritance, modularity, and other mechanisms for reducing complexity and preventing error. If multi-agent systems are to become widely accepted as a basis for large-scale applications, adequate agent-oriented methodologies and modelling techniques will be essential. This is not just to ensure that systems are reliable, maintainable, and conformant, but to allow their design, implementation, and maintenance to be carried out by software analysts and engineers rather than researchers. In this paper we describe an agent-oriented methodology and modelling technique for systems of agents based upon the Belief-Desire-Intention (BDI) paradigm. Our models extend existing Object-Oriented (OO) models. By building upon and adapting existing, well-understood techniques, we take advantage of their maturity to produce an approach that can be easily learnt and understood by those familiar with the OO paradigm.
13363707
Teamwork via Team Plans in Intelligent Autonomous Agent Systems
Intelligent agent systems are developing into an important paradigm in Artificial Intelligence and in general computer science. An agent can be seen as an autonomous system that perceives and acts on its environment, performing tasks and pursuing goals independently of user control. Recently, there has been much research interest directed toward the design of multi-agent systems that act collaboratively on tasks that are too complex for any single agent to perform on its own. We discuss the design and implementation of teamwork amongst autonomous agent systems. In particular, we describe an approach, using team plans, that addresses a number of important issues, such as: balancing autonomous behaviour with commitment to team behaviour; team formation; distribution of tasks amongst team members; coordination and synchronisation of actions.
38878591
Social and Individual Commitment
Agents interacting in team environments make use of a social structure which, Castelfranchi has recently claimed, must be modelled by commitments which are external to any particular agent. Such social commitments are between agents, though usually with respect to some action or state which the committed agent is prepared to perform or achieve. We start with Castelfranchi's concept of social commitment and formalise aspects of it within the BDI agent framework. We use this formalisation to characterise different sorts of social behaviour in the interaction between agents.
15317926
Planned Team Activity
Agents situated in dynamic environments can be supplied in advance with a repertoire of plans that permit them to rapidly generate appropriate sequences of actions in response to important events. When agents can form teams, new problems emerge regarding the representation and execution of joint actions. In this paper we introduce a language for representing joint plans for teams of agents, we describe how agents can organize the formation of a suitably skilled team to achieve a joint goal, and we explain how such a team can execute these plans to generate complex, synchronized team activity. The formalism provides a framework for representing and reasoning about joint actions in which various approaches to co-ordination and commitment can be explored.
27820977
A Monotonic Formalism for Events and Systems of Events
The aim of this paper is to provide a basis for a theory of events and systems of events that can be used for reasoning about arbitrarily complex dynamic domains involving multiple agents. The approach is based on a model of events that explicitly represents the domain of influence of each event By restricting the scope of an event's domain of influence, most of the problems that have seriously troubled the more conventional state-transition models of events can be avoided. The effect of performing events, either in isolation or in parallel with other events, is described. A formalism is developed that allows reasoning about arbitrarily complex behaviours. It is shown how this formalism avoids the frame problem yet allows the ramifications of any given event occurrence to be modelled without the introduction of non-monotonic mechanisms. Finally, the notion of system is introduced to provide a compositional means for reasoning about complex
205124426
Computing Grasp Functions
Abstract The grasp function of a planar part, characterized by extrema in the part's width function, can be used to analyze grasp mechanics. In particular, it can predict the final orientation of the part when it is grasped with a parallel-jaw gripper. This information allows us to derive a sequence of grasp angles that will orient the part up to symmetry in the grasp function. In previous papers the grasp function was assumed given as input; in this paper we present a linear-time algorithm for computing the grasp function of a part bounded by n algebraic arcs given in parametric form. We also show that the algorithm can be extended to compute a related function that describes the outcome of first pushing and then grasping the part.
9505205
Mixed Mode XML Query Processing
Querying XML documents typically involves both tree-based navigation and pattern matching similar to that used in structured information retrieval domains. In this paper, we show that for good performance, a native XML query processing system should support query plans that mix these two processing paradigms. We describe our prototype native XML system, and report on experiments demonstrating that even for simple queries, there are a number of options for how to combine tree-based navigation and structural joins based on information retrieval-style inverted lists, and that these options can have widely varying performance. We present ways of transparently using both techniques in a single system, and provide a cost model for identifying efficient combinations of the techniques. Our preliminary experimental results prove the viability of our approach.
6556030
A pivoting gripper for feeding industrial parts
To be cost effective and highly precise, many industrial assembly robots have only four degrees of freedom (DOF) plus a binary pneumatic gripper. Such robots commonly permit parts to be rotated only about a vertical axis. However it is often necessary to reorient parts about other axes prior to assembly. In this paper the authors describe a way to orient parts about an arbitrary axis by introducing a rotating bearing between the jaws of a simple gripper. Based on this mechanism, the authors are developing a rapidly configurable vision-based system for feeding parts. In this system, a camera determines initial part pose; the robot then reorients the part to achieve a desired final pose. The authors have implemented a prototype version in their laboratory using a commercially-available robot system.<<ETX>>
205493040
Probabilities of therapeutic extinction of HIV
Using branching process principles and recent developments in HIV immunology, a methodology is demonstrated to compute the probability of extinction of HIV in the presence of protease inhibitors.
11388485
The number of reachable pairs in a digraph
For a digraph G, let R(G) (respectively, R^(^k^)(G)) be the number of ordered pairs (u,v) of vertices of G such that u v and v is reachable from u (respectively, reachable from u by a path of length ==k+(k+1)^0^.^5^7+2, for arbitrary k.