1,721,442 research outputs found
Boredom makes me ‘nervous’: fidgeting as a strategy for contrasting the lack of variety
Full text linkVigilance decrement is a relevant problem in critical contexts requiring occasional response after a prolonged period of inactivity. Although many studies describe boredom as the leading cause in depleting attentional resources, the understanding of its relationship with human performance has been limited by the unavailability of objective measures. This study attempts to overcome this limitation by focusing on fidgeting (namely, repetitive and involuntary body movements) as a behavioural correlate of boredom. A laboratory study was devised for comparing the individuals’ performance to two versions of the same task characterised by two boredom levels. Movements were detected using accelerometers controlled by an Arduino board. Results showed that participants fidgeted more in the condition operationalised as less boring than in the more boring one. Result of this study are interpreted as supporting the idea that an increase in fidgeting may have a functional role, and that it might be used by individuals for introducing variability where it lacks. Overall, fidgeting appears to be promising candidate measure for that could be used in many operational settings for the assessment of the operator functional state
Physics-based Demand Model and Fragility Functions of Industrial Tanks under Blast Loading
Full text linkBlast hazards represent a serious threat to industrial facilities. Past explosion incidents highlight the severe consequences of such events. A probabilistic approach can help industries and designers mitigate the consequences of blast loading by better organizing industrial plants. In this paper, we propose a physics-based probabilistic demand model and formulate the reliability problem for industrial steel tanks under blast loading. Starting from a deterministic Single-Degree-of-Freedom (SDOF) model based on Donnell shallow-shell theory, we develop a correction term that improves the model accuracy due to the simplified representation of the SDOF model. We use Bayesian inference to estimate the unknown model parameters in the correction term and model error, combining predictions from the SDOF model with experimental data and any prior information. To illustrate, we estimate the reliability of an example cylindrical steel tanks subject to blast loading considering three damage levels. The reliability analysis yields a set of fragility curves that represent the conditional probability of the bending failure of the tank given a scaled distance, as the load intensity measure. Then, as an example, we use the developed fragility functions to estimate the reliability of a chemical industrial facility considering different explosion scenarios
Time-Dependent Probability of Exceeding a Target Level of Recovery
Full text linkThe resilience of a system is generally defined in terms of its ability to withstand external perturbations, adapt, and rapidly recover. This paper introduces a probabilistic formulation to predict the recovery process of a system given past recovery data and to estimate the probability of reaching or exceeding a target value of functionality at any time. A Bayesian inference is used to capture the changes over time of model parameters as recovery data become available during the work progress. The proposed formulation is general and can be applied to continuous recovery processes such as those of economic or natural systems, as well as to discrete recovery processes typical of engineering systems. As an illustration of the proposed formulation, two examples are provided. The paper models the recovery of a reinforced concrete bridge following seismic damage, as well as the population relocation after the occurrence of a seismic event when no data on the duration of the recovery are available a priori
Memory for positional movements as a component of the visuospatial working memory
No full textThough the Corsi block-tapping task (CBT) is widely used for assessing visuospatial memory, information about what exactly it measures is still debated. We investigated such issue by observing how motor, visual, and spatial secondary tasks affect the performance on three versions of the CBT. Results showed a double dissociation pattern, wherein two motor secondary tasks had larger effects when the CBT was administered by the examiner tapping on the blocks. A spatial secondary task had larger effects when the CBT was administered by automatically illuminating the blocks. Finally, a visual secondary task had larger effects on a two-dimensional, computerized version of the CBT. These findings suggest that memory for movements plays a relevant role in the CBT, and are especially relevant due to their implications for assessment of brain-damaged patients, besides providing further evidence of a fractionation of visuospatial memory into multiple subcomponent
Study on the Role of the Cardiovascular Aging Factors on the Development of the Extrapyramidal Syndrome of Tardive Dyskinesia
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
- …
