The WorkPlace distributed processing environment

Real time control problems require robust, high performance solutions. Distributed computing can offer high performance through parallelism and robustness through redundancy. Unfortunately, implementing distributed systems with these characteristics places a significant burden on the applications programmers. Goddard Code 522 has developed WorkPlace to alleviate this burden. WorkPlace is a small, portable, embeddable network interface which automates message routing, failure detection, and re-configuration in response to failures in distributed systems. This paper describes the design and use of WorkPlace, and its application in the construction of a distributed blackboard system

Knowledge-Based Support for Management of Concurrent, Multidisciplinary Design

Artificial intelligence (AI) applications to design have tended to focus on modeling and automating aspects of single discipline design tasks. Relatively little attention has thus far been devoted to representing the kinds of design \u27metaknowledge\u27 needed to manage the important interface issues that arise in concurrent design, that is, multidisciplinary design decision-making. This paper provides a view of the process and management of concurrent design and evaluates the potential of two AI approaches—blackboard architectures and co-operative distributed problem-solving (CDPS)—to model and support the concurrent design of complex artifacts. A discussion of the process of multidisciplinary design highlights elements of both sequential and concurrent design decision-making. We identify several kinds of design metaknowledge used by expert managers to: partition the design task for efficient execution by specialists; set appropriate levels of design conservatism for key subsystem specifications; evaluate, limit and selectively communicate design changes across discipline boundaries; and control the sequence and timing of the key (highly constrained and constraining) design decisions for a given type of artifact. We explore the extent to which blackboard and CDPS architectures can provide valid models of and potential decision support for concurrent design by (1) representing design management metaknowledge, and (2) using it to enhance both horizontal (interdisciplinary) and vertical (project life cycle) integration among product design, manufacturing and operations specialists

Proceedings ICPW'07: 2nd International Conference on the Pragmatic Web, 22-23 Oct. 2007, Tilburg: NL

Proceedings ICPW'07: 2nd International Conference on the Pragmatic Web, 22-23 Oct. 2007, Tilburg: N

Multi Agent Systems in Logistics: A Literature and State-of-the-art Review

Based on a literature survey, we aim to answer our main question: “How should we plan and execute logistics in supply chains that aim to meet today’s requirements, and how can we support such planning and execution using IT?†Today’s requirements in supply chains include inter-organizational collaboration and more responsive and tailored supply to meet specific demand. Enterprise systems fall short in meeting these requirements The focus of planning and execution systems should move towards an inter-enterprise and event-driven mode. Inter-organizational systems may support planning going from supporting information exchange and henceforth enable synchronized planning within the organizations towards the capability to do network planning based on available information throughout the network. We provide a framework for planning systems, constituting a rich landscape of possible configurations, where the centralized and fully decentralized approaches are two extremes. We define and discuss agent based systems and in particular multi agent systems (MAS). We emphasize the issue of the role of MAS coordination architectures, and then explain that transportation is, next to production, an important domain in which MAS can and actually are applied. However, implementation is not widespread and some implementation issues are explored. In this manner, we conclude that planning problems in transportation have characteristics that comply with the specific capabilities of agent systems. In particular, these systems are capable to deal with inter-organizational and event-driven planning settings, hence meeting today’s requirements in supply chain planning and execution.supply chain;MAS;multi agent systems

MULTIPLE AGENT FORMALISMS FOR COORDINATION IN ORGANIZATIONAL PROBLEMS

Many organizational problems are ill-structured where the structure of a problem is not apparent at the outset of the problem solving process. Agents responsible for these problems often decompose them into subproblems the solution of which is the responsibility of other agents. These problems are only nearly independent in the sense that temporal and technical dependencies exist between the different subproblems. Since the problems are interdependent, coordinating the activities of the different agents is important for ensuring that the partial solutions discovered by these different agents are not conflicting in terms of global consistency. Usual mechanisms for coordination include communication and negotiation between agents of interrelated problems. In this paper we describe a formalism for coordination in multiple agent ill-structured problems based on four properties of tasks, atomicity, serializability, completeness and soundness. We examine how these properties are essential for handling conflict resolution. We also outline some requirements for control.Information Systems Working Papers Serie

Approaches to case analyses in synchronous and asynchronous environments

Computer-mediated communication (CMC) tools can be used to integrate time-intensive tasks, such as case study analyses, more easily into the teacher education curriculum. How students talk together online for learning purposes in CMC environments is an area that has not yet been thoroughly investigated. This paper extends findings from a previous study by comparing two groups of four preservice teachers analyzing cases in a synchronous and asynchronous environment. A case study and computer-mediated discourse analysis approach was taken to make sense of the discussion transcripts and participant reflections. Booth and Hulten’s (2003) taxonomy of learning contributions is used as an analysis framework. Asymmetrical participation patterns were found in both modes, with more participatory contributions to establish presence made in the asynchronous mode. More interactive moves were contributed in the synchronous mode. Reflective contributions, mainly to agree, were present in both modes. One group chose the asynchronous and the other the synchronous environment to analyze the final case of the course. Implications for the design and analysis of case discussion tasks in CMC environments are discussed