629 research outputs found

    Azione e cognizione: uno studio sull'effetto del movimento nella percezione del tempo

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    A feature of temporal cognition is that it is built on properties linked to action (i.e., duration, speed and rhythm). It is therefore plausible to assume that temporal perception and representation are affected by motor experience. The present study investigated the influence of movement in a time-estimation task (i.e., to beat a drum concurrently with a rhythmic sound acoustically perceived) in the presence (i.e., experimental group) or in the absence (i.e., control group) of a movement performed between two subsequent beats. Findings showed that experimental group is more accurate than control group probably because it benefited of more information: those from the soundtrack and those from the proprioceptive sensors involved in the movement of the arm

    Towards a Framework for Automatic Firewalls Configuration via Argumentation Reasoning

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    Firewalls have been widely used to protect not only small and local networks but also large enterprise networks. The configuration of firewalls is mainly done by network administrators, thus, it suffers from human errors. This paper aims to solve the network administrators' problem by introducing a formal approach that helps to configure centralized and distributed firewalls and automatically generate conflict-free firewall rules. We propose a novel framework, called ArgoFiCo, which is based on argumentation reasoning. Our framework automatically populates the firewalls of a network, given the network topology and the high-level requirements that represent how the network should behave. ArgoFiCo provides two strategies for firewall rules distribution

    Inhomogeneous point-process entropy: an instantaneous measure of complexity in discrete systems

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    Measures of entropy have been widely used to characterize complexity, particularly in physiological dynamical systems modeled in discrete time. Current approaches associate these measures to finite single values within an observation window, thus not being able to characterize the system evolution at each moment in time. Here, we propose a new definition of approximate and sample entropy based on the inhomogeneous point-process theory. The discrete time series is modeled through probability density functions, which characterize and predict the time until the next event occurs as a function of the past history. Laguerre expansions of the Wiener-Volterra autoregressive terms account for the long-term nonlinear information. As the proposed measures of entropy are instantaneously defined through probability functions, the novel indices are able to provide instantaneous tracking of the system complexity. The new measures are tested on synthetic data, as well as on real data gathered from heartbeat dynamics of healthy subjects and patients with cardiac heart failure and gait recordings from short walks of young and elderly subjects. Results show that instantaneous complexity is able to effectively track the system dynamics and is not affected by statistical noise properties

    Heart rate variability in marketing research: A systematic review and methodological perspectives

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    Heart rate variability is a promising physiological measurement that accesses psychophysiological variations in response to a marketing stimulus. While its application spans diverse fields, there is a limited understanding of the usability and interpretation of heart rate variability in marketing research. Therefore, this hybrid literature review provides an overview of the emerging use of heart rate variability in marketing research, along with essential methodological considerations. In this context, we blend marketing mix framework with stimulus-organism-response theory, segregating the use of heart rate variability in various marketing research contexts. We follow the preferred reporting items for systematic reviews and meta-analyses (PRISMA) framework to reflect on 33 records obtained from six databases. Our findings suggest that 42% of studies used heart rate variability to investigate promotion-related topics. Overall, heart rate variability is mostly used in combination with Galvanic skin response (48%). Further, 39% of studies used non-portable systems for data collection. Last, using the theory characteristics methodology (TCM) framework, we identified six research avenues: (1) affective, cognitive, and sensorial constructs; (2) personality, thinking style, and demographics; (3) product experience; (4) advertising and branding; (5) correlation with immersive technologies; and (6) triangulation with other neurophysiological tools

    A hybrid threat model for smart systems

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    Cyber-physical systems and their smart components have a pervasive presence in all our daily activities. Unfortunately, identifying the potential threats and issues in these systems and selecting enough protection is challenging given that such environments combine human, physical and cyber aspects to the system design and implementation. Current threat models and analysis do not take into consideration all three aspects of the analyzed system, how they can introduce new vulnerabilities or protection measures to each other. In this work, we introduce a novel threat model for cyber-physical systems that combines the cyber, physical, and human aspects. Our model represents the system's components relations and security properties by taking into consideration these three aspects. Together with the threat model we also propose a threat analysis method that allows understanding the security state of the system's components. The threat model and the threat analysis have been implemented into an automatic tool, called TAMELESS, that automatically analyzes threats to the system, verifies its security properties, and generates a graphical representation, useful for security architects to identify the proper prevention/mitigation solutions. We show and prove the use of our threat model and analysis with three cases studies from different sectors

    A hybrid threat model for smart systems

    Get PDF
    Cyber-physical systems and their smart components have a pervasive presence in all our daily activities. Unfortunately, identifying the potential threats and issues in these systems and selecting enough protection is challenging given that such environments combine human, physical and cyber aspects to the system design and implementation. Current threat models and analysis do not take into consideration all three aspects of the analyzed system, how they can introduce new vulnerabilities or protection measures to each other. In this work, we introduce a novel threat model for cyber-physical systems that combines the cyber, physical, and human aspects. Our model represents the system’s components relations and security properties by taking into consideration these three aspects. Together with the threat model we also propose a threat analysis method that allows understanding the security state of the system’s components. The threat model and the threat analysis have been implemented into an automatic tool, called TAMELESS, that automatically analyzes threats to the system, verifies its security properties, and generates a graphical representation, useful for security architects to identify the proper prevention/mitigation solutions. We show and prove the use of our threat model and analysis with three cases studies from different sector

    A topological weakening and softening map as simplified tool to assess the performances recovery of hybridized natural fiber reinforced composites subjected to alternate salt-fog/dry cycle

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    While receiving a growing attention in recent years, natural fibers cannot completely replace synthetic fibers as composite reinforcement for structural applications due to both their low durability in wet or humid environments and their limited and not homogenous overall performance. In this context, the purpose of this paper is to assess the impact of a humid/dry cycle on the mechanical stability of epoxy-based laminates reinforced with flax and glass fibers by using a topological weakening and softening map as simplified tool. The objective is, preliminarily, to evaluate the influence of glass fiber hybridization on the properties recovery of flax fiber reinforced composites subjected to alternate salt-fog/dry cycle. All laminates studied were subjected to salt spray for 15 or 30 days, and then stored in a dry controlled environment (50% relative humidity and 22 °C) for up to 21 days. The results evidenced that, compared to flax fiber reinforced composites, the glass hybridization of flax composite significantly reduce the mechanical performances degradation over time during the humid stage (about 28.0% better than flax one in stiffness). Furthermore, the mechanical performance recovery is promoted during the dry stage. A simplified topological map was lastly developed to graphically assess the decline and recovery of composites’ performances during the humid/dry cycle, amplifying the application and design effects of this approach

    In situ monitoring of moisture uptake of flax fiber reinforced composites under humid/dry conditions

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    The use of green materials such as natural fiber-reinforced composites represents an increasingly stringent prerogative in the future planning of industrial and non-industrial production. The optimization of these materials is the main aim of the current research, focused on the evaluation of the behavior of flax fiber reinforced composites exposed to isothermal adsorption and desorption cycles, at varying the partial pressure of water vapor (P/P0). For this purpose, the moisture uptake and the morphology changes of the composite material and their constituents were in situ monitored through a measurement protocol, by using a dynamic vapor sorption (DVS) analysis, coupled with an environmental scanning electron microscopy (ESEM) visual investigation. A dependence of moisture uptake and diffusivity on the composite morphology was clearly detected. In particular, no significant variation in the morphology of the specimen is noticed at low water vapor partial pressure (i.e., P/P0 up to 5.4%) due to the limited absorption capacity (i.e., lower than 1%). On the other hand, fibers morphology changes at increasing the partial pressure up to 25.1%, showing a sensitive increase in volume. This phenomenon becomes much more relevant for high relative humidity values (i.e., ~90%), reaching more than 6% of absorption capacity
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