31,532 research outputs found

    Optimizing genetic algorithm strategies for evolving networks

    Full text link
    This paper explores the use of genetic algorithms for the design of networks, where the demands on the network fluctuate in time. For varying network constraints, we find the best network using the standard genetic algorithm operators such as inversion, mutation and crossover. We also examine how the choice of genetic algorithm operators affects the quality of the best network found. Such networks typically contain redundancy in servers, where several servers perform the same task and pleiotropy, where servers perform multiple tasks. We explore this trade-off between pleiotropy versus redundancy on the cost versus reliability as a measure of the quality of the network.Comment: 9 pages, 5 figure

    Evolving hierarchical visually guided neural network agents to investigate complex interactions.

    Get PDF
    A complex system is a system with a large number of interacting components without any mechanism for central control that displays self organisation. Understanding how these interactions affect the overall behaviour of a system is of great interest to science. Indeed, researchers use a wide variety of models to investigate complex systems. The problem with most models is that they disregard the hierarchical nature of complex systems: they ignore the fact that components of real world systems tend to be complex systems as well. This prevents researchers from investigating the interactions taking place between the lower and the higher levels of the model which may be crucial in order to gain a full understanding of the examined phenomena and of complex systems in general. Therefore, this thesis introduces Mosaic World, a multi-agent model for the purpose of investigating interactions (focusing on 'complex' multilevel interactions) within a hierarchical complex system, in addition to other computational and biological hypotheses. Mosaic World comprises a population of evolving neural network agents that inhabit a changing visual environment. By analysing the interactions that occur within Mosaic World, this thesis demonstrates the importance of incorporating hierarchical complexity into a model, and contributes to our understanding of hierarchical complex systems by showing how selective pressures cause differentiation across levels. Additionally, the study of multilevel interactions is used to probe several hypotheses and provides the following contributions among others: Analysis of agent evolvability as affected by the usage of different types of structural mutations in the evolutionary process. Demonstration that agents controlled by modular neural networks are fitter than agents that are controlled by non-modular neural networks the improvement in fitness occurs through specialisation of modules. Empirical support for a biological theory suggesting that colour vision evolved as a method of dealing with ambiguous stimuli

    Seven HCI Grand Challenges

    Get PDF
    This article aims to investigate the Grand Challenges which arise in the current and emerging landscape of rapid technological evolution towards more intelligent interactive technologies, coupled with increased and widened societal needs, as well as individual and collective expectations that HCI, as a discipline, is called upon to address. A perspective oriented to humane and social values is adopted, formulating the challenges in terms of the impact of emerging intelligent interactive technologies on human life both at the individual and societal levels. Seven Grand Challenges are identified and presented in this article: Human-Technology Symbiosis; Human-Environment Interactions; Ethics, Privacy and Security; Well-being, Health and Eudaimonia; Accessibility and Universal Access; Learning and Creativity; and Social Organization and Democracy. Although not exhaustive, they summarize the views and research priorities of an international interdisciplinary group of experts, reflecting different scientific perspectives, methodological approaches and application domains. Each identified Grand Challenge is analyzed in terms of: concept and problem definition; main research issues involved and state of the art; and associated emerging requirements

    Towards an ABM-Based Framework for Investigating Consumer Behaviour in the Insurance Industry

    Get PDF
    This paper presents a framework that builds upon agent-based modelling for investigating the behaviour of consumers in the insurance industry. Consumers are modelled as agents and clustered in groups reflecting their income levels. Agents that model consumers are characterised by their socio-demographic features and interact with other insurance consumer-agents by means of local and global social networks. Furthermore, the environment in which they evolve models the impact of external factors such as mortality, disease and other accident rates as well as insurance culture. This makes that consumer-agents accumulate experience, improve their understanding and knowledge of financial products, and thus develop their perception of need for security and consider the usefulness of insurance services. In turn, the framework enables to model the construction of the customers’ insurance product purchase decision.p

    Meme transmission in artificial proto-cultures

    Get PDF
    corecore