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71.
Valeria Cirillo Arianna Martinelli Alessandro Nuvolari Matteo Tranchero 《Research Policy》2019,48(4):905-922
One of the most significant results of the qualitative literature on national systems of innovation (NSIs) is that different systemic arrangements (i.e. configurations of actors and institutions) can deliver similar levels of innovative performance. Using factor analysis on a novel dataset of 29 quantitative indicators of innovative activities we provide an empirical characterization of the structure of European NSIs over the last ten years. Our results cast doubt on the empirical significance of the “equifinality” of heterogeneous systemic arrangements in the context of NSI. Innovation systems show inherent complexity, which leads to a high level of complementarity among their constituent components and configuration. This result implies that successful innovation policies should be systemic, leaving little flexibility in policy design and scope. 相似文献
72.
Gianfranco Gagliardi Francesco Tedesco Alessandro Casavola 《Journal of The Franklin Institute》2018,355(14):6710-6745
This paper illustrates the derivation of a linear parameter varying (LPV) model approximation of a turbocharged Spark-Ignition (SI) automotive engine and its usage in designing a model-based fault detection and isolation (FDI) scheme. The LPV approximation is derived from a detailed nonlinear mathematical model of the engine on the basis of the well known Jacobian approach. The resulting LPV representation is then exploited for synthesizing a bank of LPV-FDI Luenberger observers. Each observer is in charge of detecting a particular class of fault and is designed for having low sensitivity to all other exogenous inputs so as to allow an effective fault isolation. The adopted FDI scheme is gain-scheduled and exploits a set of engine variables, assumed to be measurable on-line, as a scheduling parameters. The goodness of the LPV approximation of the engine model and the effectiveness of the LPV-FDI architecture are demonstrated by several numerical simulations. 相似文献
73.
Alessandro H. N. Ré Samuel W. Logan Maria T. Cattuzzo Rafael S. Henrique Mariana C. Tudela David F. Stodden 《Journal of sports sciences》2018,36(1):1-6
This study compared performances and motor delay classifications for the Test of Gross Motor Development-2nd edition (TGMD-2) and the Körperkoordinationstest Für Kinder (KTK) in a sample of 424 healthy children (47% girls) between 5 and 10 years of age. Low-to-moderate correlations (r range = 0.34–0.52) were found between assessments across age. In general, both boys and girls demonstrated higher raw scores across age groups. However, percentile scores indicated younger children outperformed older children, denoting a normative percentile-based decrease in motor competence (MC) in the older age groups. In total, the TGMD-2 and KTK classified 39.4% and 18.4% children, respectively, as demonstrating very low MC (percentile ≤5). In conclusion, the TGMD-2 classified significantly more children with motor delays than the KTK and the differences between children’s motor skill classification levels by these assessments became greater as the age groups increased. Therefore, the TGMD-2 may demonstrate more susceptibility to sociocultural influences and be more influenced by cumulative motor experiences throughout childhood. Low-to-moderate correlations between assessments also suggest the TGMD-2 and KTK may measure different aspects of MC. As such, it may be important to use multiple assessments to comprehensively assess motor competence. 相似文献
74.
Xinghua Liu Alessandro N. Vargas Xinghuo Yu Long Xu 《Journal of The Franklin Institute》2017,354(14):5813-5824
This paper presents a stabilizing control for two-dimensional stochastic differential equations. The stability concept in this study is the stability in probability. To ensure such a stability, the control is designed based on the sliding mode technique, and applied to account stochastic systems. This finding has a practical implication—the proposed control can be used to stabilize a real-time automotive electronic throttle valve. The proposed approach is verified by data collected from experiments. 相似文献
75.
The objective assessment of the prestige of an academic institution is a difficult and hotly debated task. In the last few years, different types of university rankings have been proposed to quantify it, yet the debate on what rankings are exactly measuring is enduring.To address the issue we have measured a quantitative and reliable proxy of the academic reputation of a given institution and compared our findings with well-established impact indicators and academic rankings. Specifically, we study citation patterns among universities in five different Web of Science Subject Categories and use the PageRank algorithm on the five resulting citation networks. The rationale behind our work is that scientific citations are driven by the reputation of the reference so that the PageRank algorithm is expected to yield a rank which reflects the reputation of an academic institution in a specific field. Given the volume of the data analysed, our findings are statistically sound and less prone to bias, than, for instance, ad–hoc surveys often employed by ranking bodies in order to attain similar outcomes. The approach proposed in our paper may contribute to enhance ranking methodologies, by reconciling the qualitative evaluation of academic prestige with its quantitative measurements via publication impact. 相似文献
76.
Alessandro Antonietti Chiara Rasi Ernesto Imperio Marco Sacco 《Education and Information Technologies》2000,5(4):317-327
Students' opinions about the opportunities and the implications of VR in instruction were investigated by administering a questionnaire to humanities and engineering undergraduates. The questionnaire invited participants to rate a series of statements concerning motivation and emotion, skills, cognitive styles, benefits and learning outcomes associated with the use of VR in education. The representation which emerged was internally consistent and articulated into specific dimensions. It was not affected by gender, by the previous use of VR software, or by the knowledge of the main topics concerning the introduction of IT in instruction. Also the direct participation in a training session based on an immersive VR experience did not influence such a representation, which was partially modulated by the kind of course attended by students. 相似文献
77.
Federico Y. Fontana Alessandro L. Colosio Daniel A. Keir Juan M. Murias 《Journal of sports sciences》2017,35(22):2191-2197
We tested the hypothesis that critical intensity in cycling can be determined from a single delta blood lactate in the third minute of a submaximal cycle ergometer trial. Fourteen healthy young men performed four to six constant-power-output trials on a cycle ergometer to the limit of tolerance. Critical intensity was calculated via a linear model and subsequently validated. Lactate was measured at baseline and at 3 min from exercise onset. Delta lactate was the difference between these measures. Based on individual trials, we obtained the delta lactate–% validated critical intensity relationship and thereafter an estimate of critical intensity was computed. Validated and estimated critical intensity were compared by effects sizes, paired-sample t-test and Bland–Altman analysis. Delta lactate was a linear function of the intensity of exercise, expressed as % validated critical intensity (R2 = 0.89). Estimated critical intensity was not different from (d = 0.03, P = 0.98) and highly correlated with (R2 = 0.88) validated critical intensity. The bias between measures was 0.03 W (≠0) with a precision of 7 W. The results suggest that critical intensity in cycling can be accurately and precisely determined from delta lactate during a sub-maximal trial and so provides a practical and valid alternative to direct determination. 相似文献
78.
Alessandro Russo 《Inter-Asia Cultural Studies》2013,14(4):673-682
Abstract In the Chinese Cultural Revolution – the epicenter of the last great political sequence at worldwide level in the 1960s and 1970s – the flashing of unprecedented possibilities of post‐party politics was entangled with the epochal closure of a network of political culture. The Cultural Revolution proves to be extremely refractory to historical investigation because it undoes the established conceptual bridges between history and politics, bridges that all other social sciences crossed for studying politics. Therefore, new theoretical perspectives and new protocols of investigation are required, and not only for those events, but in the last analysis for the study of all political situations. The author discusses three main points for finding a new perspective. First, a basic distinction should be stressed between the intermittent nature of politics – one of the rarest modes of subjectivity, which exist only in singular intellectually inventive sequences – and the structural invariance of the state, despite the incessant historical mutations of its particular forms. Moreover, the relationships between the present state of depoliticization and the previous political situations deserve close analysis. The hypothesis is that the concrete form of the state in a given moment is the hollow imprint of the last great political sequence, or that it is shaped by a reactive de‐politicization. Finally, the declarations and the related behaviors of the actors during the events are the major analytical elements in the study of politics. However, the Cultural Revolution was marked to an unprecedented degree by increasing dissonances and, finally, irremediable ruptures between the processes created by the subjective declarations and the same network of political culture within which they were formulated. 相似文献
79.
80.
Alessandro Piras Milena Raffi Monica Perazzolo Ivan Malagoli Lanzoni Salvatore Squatrito 《Journal of sports sciences》2019,37(9):980-987
Microsaccades are important fixation eye movements for visual scene perception. Compared to novices, athletes make fewer fixations of longer duration toward limited interest areas crucial for action prediction. Thus, our aim was to study the microsaccade features during those fixations. Gaze behaviour of expert and novice table tennis players was recorder during a task in which subjects were instructed to predict the direction of the ball after the opponent’s throw. Three interest areas from the opponent’s body and one from the ball trajectory were identified. We analysed correctness of predictions, fixations, microsaccades and saccades to estimate the relationship between eye movements toward interest areas and success in the task. Compared to novices, experts fixated more on hand-racket during forehand and on trunk during backhand drive technique. Longer fixations on hand-racket and trunk were associated with higher microsaccade rate with a narrower directional distribution of them. It probably means that athletes focused their gaze on these small areas, suggesting enhanced attention mainly to them, and fewer consideration for the surrounding regions. We can assume that microsaccade rate and average direction could be related to the salience of interest areas during performance. 相似文献