Introduction to the Special Issue: The AgentLink III Technical Forums

This article introduces the special issue of ACM Transactions on Autonomous and Adaptive Systems devoted to research papers arising from the three Technical Forum Group meetings held in 2004 and 2005 that were organized and sponsored by the European FP6 Coordination Action AgentLink III

Isomorphism Checking in GROOVE

In this paper we show how isomorphism checking can be used as an effective technique for symmetry reduction in graph-based state spaces, despite the inherent complexity of the isomorphism problem. In particular, we show how one can use element-based graph certificate mappings to help in recognising nonisomorphic graphs. These are mappings that assign to all elements (edges and nodes) of a given graph a number that is invariant under isomorphism, in the sense that any isomorphism between graphs is sure to preserve this number. The individual element certificates of a graph give rise to a certificate for the entire graph, which can be used as a hash key for the graph; hence, this yields a heuristic to decide whether a graph has an isomorphic representative in a previously computed set of graphs. We report some experiments that show the viability of this method. \u

Distributed graph-based state space generation

LTSMIN provides a framework in which state space generation can be distributed easily over many cores on a single compute node, as well as over multiple compute nodes. The tool works on the basis of a vector representation of the states; the individual cores are assigned the task of computing all successors of states that are sent to them. In this paper we show how this framework can be applied in the case where states are essentially graphs interpreted up to isomorphism, such as the ones we have been studying for GROOVE. This involves developing a suitable vector representation for a canonical form of those graphs. The canonical forms are computed using a third tool called BLISS. We combined the three tools to form a system for distributed state space generation based on graph grammars. We show that the time performance of the resulting system scales well (i.e., close to linear) with the number of cores. We also report surprising statistics on the memory\ud consumption, which imply that the vector representation used to store graphs in LTSMIN is more compact than the representation used in GROOVE

State-of-the-art in Power Line Communications: from the Applications to the Medium

In recent decades, power line communication has attracted considerable attention from the research community and industry, as well as from regulatory and standardization bodies. In this article we provide an overview of both narrowband and broadband systems, covering potential applications, regulatory and standardization efforts and recent research advancements in channel characterization, physical layer performance, medium access and higher layer specifications and evaluations. We also identify areas of current and further study that will enable the continued success of power line communication technology.Comment: 19 pages, 12 figures. Accepted for publication, IEEE Journal on Selected Areas in Communications. Special Issue on Power Line Communications and its Integration with the Networking Ecosystem. 201

Experimental and analytical performance investigation of air to air two phase closed thermosyphon based heat exchangers

In recent years, the use of wickless heat pipes (thermosyphons) in heat exchangers has been on the rise, particularly in gas to gas heat recovery applications due to their reliability and the level of contingency they offer compared to conventional heat exchangers. Recent technological advances in the manufacturing processes and production of gravity assisted heat pipes (thermosyphons) have resulted in significant improvements in both quality and cost of industrial heat pipe heat exchangers. This in turn has broadened the potential for their usage in industrial waste heat recovery applications. In this paper, a tool to predict the performance of an air to air thermosyphon based heat exchanger using the ε-NTU method is explored. This tool allows the predetermination of variables such as the overall heat transfer coefficient, effectiveness, pressure drop and heat exchanger duty according to the flow characteristics and the thermosyphons configuration within the heat exchanger. The new tool's predictions were validated experimentally and a good correlation between the theoretical predictions and the experimental data, was observed. © 2014 Elsevier Ltd. All rights reserved

Internationalisation of Innovation: Why Chip Design Moving to Asia

This paper will appear in International Journal of Innovation Management, special issue in honor of Keith Pavitt, (Peter Augsdoerfer, Jonathan Sapsed, and James Utterback, guest editors), forthcoming. Among Keith Pavitt's many contributions to the study of innovation is the proposition that physical proximity is advantageous for innovative activities that involve highly complex technological knowledge But chip design, a process that creates the greatest value in the electronics industry and that requires highly complex knowledge, is experiencing a massive dispersion to leading Asian electronics exporting countries. To explain why chip design is moving to Asia, the paper draws on interviews with 60 companies and 15 research institutions that are doing leading-edge chip design in Asia. I demonstrate that "pull" and "policy" factors explain what attracts design to particular locations. But to get to the root causes that shift the balance in favor of geographical decentralization, I examine "push" factors, i.e. changes in design methodology ("system-on-chip design") and organization ("vertical specialization" within global design networks). The resultant increase in knowledge mobility explains why chip design - that, in Pavitt's framework is not supposed to move - is moving from the traditional centers to a few new specialized design clusters in Asia. A completely revised and updated version has been published as: " Complexity and Internationalisation of Innovation: Why is Chip Design Moving to Asia?," in International Journal of Innovation Management, special issue in honour of Keith Pavitt, Vol. 9,1: 47-73.

Envisioning patient safety in Telehealth: a research perspective

This article explores the need for research into patient safety in large-scale Telehealth systems faced with the perspective of its development extended to healthcare systems. Telehealth systems give rise to significant advantages in improving the quality of healthcare services as well as bringing about the possibility of new types of risk. A theoretical framework is proposed for patient safety for its approach as an emerging property in complex socio-technical systems (CSTS) and their modelling in layers. As regards this framework, the differential characteristic Telehealth elements of the system have been identified, with a greater emphasis on the level of Telehealth system and its typical subsystems. The bases of the analysis are based on references in the literature and the experience accumulated by the researchers in the area. In particular, a case describing an example of Telehealth to control patients undergoing treatment with oral anticoagulants is used. As a result, a series of areas of research into and topics regarding Telehealth patient safety are proposed to cover the detectable gaps. Both the theoretical and practical implications of the study are discussed and future perspectives are reflected on.This research has been partially supported by grants FISPI09-90110 ‘Innovation Platform in new services based on telemedicine and e-health for chronic and dependent patients -PITES’ from the Ministry of Health & Consumer Affairs; and FISPI13-00508 ‘Innovation platform in new services based on Telemedicine and e- Health: definition, design and development of tools for interoperability, patient safety and support to decision (PITES-ISA)’ from the Ministry of Economy and Competitiveness (Secretary of State of Research, Development and Innovation). The funders had no role in the study, decision to publish, or drafting of the manuscript.S