68,884 research outputs found

    An Agent-Based Algorithm exploiting Multiple Local Dissimilarities for Clusters Mining and Knowledge Discovery

    Full text link
    We propose a multi-agent algorithm able to automatically discover relevant regularities in a given dataset, determining at the same time the set of configurations of the adopted parametric dissimilarity measure yielding compact and separated clusters. Each agent operates independently by performing a Markovian random walk on a suitable weighted graph representation of the input dataset. Such a weighted graph representation is induced by the specific parameter configuration of the dissimilarity measure adopted by the agent, which searches and takes decisions autonomously for one cluster at a time. Results show that the algorithm is able to discover parameter configurations that yield a consistent and interpretable collection of clusters. Moreover, we demonstrate that our algorithm shows comparable performances with other similar state-of-the-art algorithms when facing specific clustering problems

    Simulation of complex environments:the Fuzzy Cognitive Agent

    Get PDF
    The world is becoming increasingly competitive by the action of liberalised national and global markets. In parallel these markets have become increasingly complex making it difficult for participants to optimise their trading actions. In response, many differing computer simulation techniques have been investigated to develop either a deeper understanding of these evolving markets or to create effective system support tools. In this paper we report our efforts to develop a novel simulation platform using fuzzy cognitive agents (FCA). Our approach encapsulates fuzzy cognitive maps (FCM) generated on the Matlab Simulink platform within commercially available agent software. We firstly present our implementation of Matlab Simulink FCMs and then show how such FCMs can be integrated within a conceptual FCA architecture. Finally we report on our efforts to realise an FCA by the integration of a Matlab Simulink based FCM with the Jack Intelligent Agent Toolkit

    Web Service Testing and Usability for Mobile Learning

    Get PDF
    Based on the summary of recent renowned publications, Mobile Learning (ML) has become an emerging technology, as well as a new technique that can enhance the quality of learning. Due to the increasing importance of ML, the investigation of such impacts on the e-Science community is amongst the hot topics, which also relate to part of these research areas: Grid Infrastructure, Wireless Communication, Virtual Research Organization and Semantic Web. The above examples contribute to the demonstrations of how Mobile Learning can be applied into e-Science applications, including usability. However, there are few papers addressing testing and quality engineering issues – the core component for software engineering. Therefore, the major purpose of this paper is to present how Web Service Testing for Mobile Learning can be carried out, in addition to re-investigating the influences of the usability issue with both quantitative and qualitative research methods. Out of many mobile technologies available, the Pocket PC and Tablet PC have been chosen as the equipment; and the OMII Web Service, the 64-bit .NET e-portal and the GPS-PDA are the software tools to be used for Web Service testing

    Representing Conversations for Scalable Overhearing

    Full text link
    Open distributed multi-agent systems are gaining interest in the academic community and in industry. In such open settings, agents are often coordinated using standardized agent conversation protocols. The representation of such protocols (for analysis, validation, monitoring, etc) is an important aspect of multi-agent applications. Recently, Petri nets have been shown to be an interesting approach to such representation, and radically different approaches using Petri nets have been proposed. However, their relative strengths and weaknesses have not been examined. Moreover, their scalability and suitability for different tasks have not been addressed. This paper addresses both these challenges. First, we analyze existing Petri net representations in terms of their scalability and appropriateness for overhearing, an important task in monitoring open multi-agent systems. Then, building on the insights gained, we introduce a novel representation using Colored Petri nets that explicitly represent legal joint conversation states and messages. This representation approach offers significant improvements in scalability and is particularly suitable for overhearing. Furthermore, we show that this new representation offers a comprehensive coverage of all conversation features of FIPA conversation standards. We also present a procedure for transforming AUML conversation protocol diagrams (a standard human-readable representation), to our Colored Petri net representation

    Conceiving God: Literal and Figurative Prompt for a More Tectonic Distinction

    Get PDF
    John Sanders’ Theology in the Flesh, the first comprehensive overview of the toolkit that contemporary cognitive linguistics offers for theological appropriation, despite its remarkable success, gives rather minimal attention to blending theory, one of the discipline’s most formidable tools. This paper draws on blending theory to offer an alternative to Sanders’ chapter on conceiving God. Central to the proposal is claim that God-talk, like many of the advances in science, technology, and art, entails a kind of tectonic understanding and conceptual mapping that is neither literal nor figurative

    Empirical exploration of air traffic and human dynamics in terminal airspaces

    Full text link
    Air traffic is widely known as a complex, task-critical techno-social system, with numerous interactions between airspace, procedures, aircraft and air traffic controllers. In order to develop and deploy high-level operational concepts and automation systems scientifically and effectively, it is essential to conduct an in-depth investigation on the intrinsic traffic-human dynamics and characteristics, which is not widely seen in the literature. To fill this gap, we propose a multi-layer network to model and analyze air traffic systems. A Route-based Airspace Network (RAN) and Flight Trajectory Network (FTN) encapsulate critical physical and operational characteristics; an Integrated Flow-Driven Network (IFDN) and Interrelated Conflict-Communication Network (ICCN) are formulated to represent air traffic flow transmissions and intervention from air traffic controllers, respectively. Furthermore, a set of analytical metrics including network variables, complex network attributes, controllers' cognitive complexity, and chaotic metrics are introduced and applied in a case study of Guangzhou terminal airspace. Empirical results show the existence of fundamental diagram and macroscopic fundamental diagram at the route, sector and terminal levels. Moreover, the dynamics and underlying mechanisms of "ATCOs-flow" interactions are revealed and interpreted by adaptive meta-cognition strategies based on network analysis of the ICCN. Finally, at the system level, chaos is identified in conflict system and human behavioral system when traffic switch to the semi-stable or congested phase. This study offers analytical tools for understanding the complex human-flow interactions at potentially a broad range of air traffic systems, and underpins future developments and automation of intelligent air traffic management systems.Comment: 30 pages, 28 figures, currently under revie
    • 

    corecore