286 research outputs found

    Assessment of energy and cost effectiveness in retrofitting existing buildings

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    The construction of buildings and their operation contribute to a large proportion of total energy end-use worldwide; indeed, buildings account for 40% of the total energy consumption and for 36% of CO2 emissions in the European Union. The sector is expanding, which is bound to increase its energy consumption. In order to reduce the growing energy expenditure, the European Directive imposes the adoption of measures to improve the energy efficiency in buildings. The recast of the Directive on the Energy Performance of Buildings defined all new buildings will be nearly zero-energy buildings by the end of 2020. However, the transformation of the EU's building stock will not be completed until well after 2020 and this target can only constitute an intermediate step. Indeed, the recent Commission Roadmap for moving towards a competitive, low-carbon economy showed that emissions in the building sector could be reduced by around 90% by 2050. While new buildings should be designed as intelligent low or zero-energy buildings, refurbishment of existing building stock has many challenges and opportunities because, in the building sector, most energy is consumed by existing buildings. Since the replacement rate of existing buildings by the new-build is only around 1-3% per annum, a rapid enhancement of taking up retrofit measures on a large scale is essential for a timely reduction in global energy use and promotion of environmental sustainability. Consequently, defining minimum energy performance requirements for new and, in particular, for existing buildings represent a key element in European building codes. For this reason, EPBD recast has set out Member States must ensure that minimum energy performance requirements are set with a view to achieve cost-optimal levels for buildings, building units and buildings elements. A cost-optimal level is defined as the energy performance level which leads to the lowest cost during the estimated economic lifecycle. It must be calculated in accordance with a comparative methodology framework that is based on the global cost method. To apply this methodology Member States are expected to define a series of Reference Buildings as baseline and representative models of the national building stock. Additionally, they must define energy efficiency measures to be applied to Reference Building; these ones can be a single measure or constitute a package of measures. Reference Buildings can be exploited as a basis for analysing national building stock and the potential impacts of energy efficiency measures in order to select effective strategies for upgrading existing buildings. Finally, once estimated the Reference Building energy consumptions and the impact of the different energy efficiency measures, the costs of the different packages are estimated in order to establish which of them has the lowest global cost and, consequently, represents the cost-optimal level. Global cost method considers the initial investment, the sum of the annual costs for every year and the final value, all with reference to the starting year of the calculation period. A measure or package of measures is cost-effective when the cost of implementation is lower than the value of the benefits that result, taken over the expected life of the measure. The cost-optimal result represents that retrofit action or combination of actions that minimized the global cost. From the variety of specific results, a cost curve can be derived; the lowest part of this curve represents the economic optimum for the specific set of the analyzed energy efficiency measures. This PhD study deals with complex scenario above described. Its main objective is to examine cost-optimal analysis in order to establish if this methodology can be an appropriate tool to guide and support decisions related with buildings energy performances. In detail, a critical review of the methodology has been developed and some sensitivity analyses have been exploited in order to testing the robustness of the cost-optimal analysis results. Considering the influence that similar outcomes could have on the European energy policies and on the roadmap towards 2050, it is fundamental to evaluate, even before the same outcomes, how these are reliable. Cost-optimality as a theoretical concept is well and clearly established. However, its application is far from easy and straightforward. Indeed, cost-optimal analysis is a complex methodology characterized by an inherent degree of uncertainty in the final outputs; choices of methodology, procedural decision and complexity of much of the input data significantly affect outcomes. In addition, the research highlights that often although a cost-optimal calculation is being developed and some energy efficiency retrofit measures are individualized, there are no effective instruments, in term of energy policies and financial tools, to drive the market to increase the rate of deep renovation

    Visuomotor resonance in autism spectrum disorders

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    When we observe the actions performed by others, our motor system “resonates” along with that of the observed agent. Is a similar visuomotor resonant response observed in autism spectrum disorders (ASD)? Studies investigating action observation in ASD have yielded inconsistent findings. In this perspective article we examine behavioral and neuroscientific evidence in favor of visuomotor resonance in ASD, and consider the possible role of action-perception coupling in social cognition. We distinguish between different aspects of visuomotor resonance and conclude that while some aspects may be preserved in ASD, abnormalities exist in the way individuals with ASD convert visual information from observed actions into a program for motor execution. Such abnormalities, we surmise, may contribute to but also depend on the difficulties that individuals with ASD encounter during social interaction

    Object temporal connotation

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    Time and neglect: Abnormal temporal dynamics in unilateral spatial neglect

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    The ontology of neglect. Consciousness and Cognition

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    When seeing is more than looking:Intentional gaze modulates object desirability

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    Objects in the environment have a perceived value that can be changed through social influence. A subtle way to influence object evaluation is through eye gaze: Objects looked at by others are perceived as more likable than objects that are not looked at. In 3 experiments, we directly tested the hypothesis that this liking effect depends on the processing of the intentional relation between other's eye gaze and the object being looked at. To this end, we used a novel paradigm in which participants observed a face looking left or right behind an opaque barrier. Under all tested conditions, we found a gaze cueing effect on attention: Looked-at objects were categorized faster than looked-away objects. In contrast, observed gaze only led to a boost in affective evaluation for the target object when observers had the impression that the face could see the object behind the barrier, but not when observers had the impression that the face could not see the object. These findings indicate that observers make a sophisticated use of social gaze cues in the affective evaluation of objects: Objects looked at by others are liked more than objects looked away but only when others can see the objects

    Modulation of corticospinal output during goal-directed actions: Evidence for a contingent coding hypothesis.

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    Abstract Seeing a person perform an action activates the observer's motor system. The present study aimed at investigating the temporal relationship between execution and observation of goal-directed actions. One possibility is that the corticospinal excitability (CSE) follows the dynamic evolution of the pattern of muscle activity in the executed action. Alternatively, CSE may anticipate the future course of the observed action, prospectively extrapolating future states. Our study was designed to test these alternative hypotheses by directly comparing the time course of muscle recruitment during the execution and observation of reach-to-grasp movements. We found that the time course of CSE during action observation followed the time course of the EMG signal during action execution. This contingent coding was observed despite the outcome of the observed motor act being predictable from the earliest phases of the movement. These findings challenge the view that CSE serves to predict the target of an observed action

    What Will I Do Next? The Intention from Motion Experiment

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    In computer vision, video-based approaches have been widely explored for the early classification and the prediction of actions or activities. However, it remains unclear whether this modality (as compared to 3D kinematics) can still be reliable for the prediction of human intentions, defined as the overarching goal embedded in an action sequence. Since the same action can be performed with different intentions, this problem is more challenging but yet affordable as proved by quantitative cognitive studies which exploit the 3D kinematics acquired through motion capture systems. In this paper, we bridge cognitive and computer vision studies, by demonstrating the effectiveness of video-based approaches for the prediction of human intentions. Precisely, we propose Intention from Motion, a new paradigm where, without using any contextual information, we consider instantaneous grasping motor acts involving a bottle in order to forecast why the bottle itself has been reached (to pass it or to place in a box, or to pour or to drink the liquid inside). We process only the grasping onsets casting intention prediction as a classification framework. Leveraging on our multimodal acquisition (3D motion capture data and 2D optical videos), we compare the most commonly used 3D descriptors from cognitive studies with state-of-the-art video-based techniques. Since the two analyses achieve an equivalent performance, we demonstrate that computer vision tools are effective in capturing the kinematics and facing the cognitive problem of human intention prediction.Comment: 2017 IEEE Conference on Computer Vision and Pattern Recognition Workshop
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