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71.
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
72.
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
73.
Maria Chiara Gallotta Valerio Bonavolontà Gian Pietro Emerenziani Emanuele Franciosi Alessandro Tito Laura Guidetti 《Journal of sports sciences》2015,33(11):1173-1181
The aim of the study was to evaluate the dorsal and lumbar spine of expert and recreational tennis players before (pre) and after (post) two different training sessions. The sample consisted of 17 male tennis players, nine expert and eight recreational males (age 21.2 ± 1.6 years). We assessed the back surface by rasterstereography pre and post two different training sessions both lasting 1.5 h: a standard training and a specific over-shoulder shots training session, respectively. Lordotic and kyphotic angle, length, imbalance, inclination for trunk, pelvic torsion, left and right lateral deviation and surface rotation were measured. Tennis expertise (expert versus recreational) significantly affected the surface rotation and right lateral deviation (P < 0.05). Trunk length was affected by intervention (pre versus post) (P < 0.05). Left lateral deviation differed both for type of session (session 1 versus session 2) and intervention (P < 0.001, P < 0.05). Expert tennis players had higher values on surface rotation and right lateral deviation, around or just above physiological values (0–5° and 0–5 mm, respectively). Type of session significantly affected left lateral deviation, indicating that over-shoulder shots lead to a higher stress for the spine; the workload produced by both single sessions led to a shortening effect on trunk length. A single training session can induce acute modifications in some parameters of dorsal and lumbar spine of players. 相似文献
74.
Matteo Vidali Enrica Verzotti Nicole Cabraz Francesca Santi Alessia Puma Giorgio Bellomo Alessandro Lupi Giuseppe Lippi Gian Carlo Avanzi 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2015,25(3):421-429
Introduction
The aim of this study was to identify clinical variables which may be independently associated with positivity of a cardiac troponin I (cTnI) assay in a large population of patients admitted to the emergency department (ED).Materials and methods
3166 subjects, with at least two troponin I tests ordered within 6 hours in the ED, were studied. Patient data were statistically analyzed to identify clinical associations with increased values of Troponin I.Results
Although patients with diagnosis of acute coronary syndrome displayed troponin I values significantly higher than those of other groups, positivity to troponin I (> 40 ng/L) was also observed in patients with other clinical conditions. In multivariate analysis, age, elevated heart rate and electrocardiographyc changes were independently associated with troponin I positivity at admission. In the whole study population troponin I positivity exhibited high sensitivity and negative predictive value, counterbalanced by low specificity and limited positive predictive value.Conclusions
Troponin I positivity should be combined with history and clinical evaluation and cautiously interpreted in the ED, especially in patients exhibiting factors associated with higher troponin I levels such as older age, elevated heart rate or ECG changes.Key words: troponin I, acute coronary syndrome, emergency service, hospital, chest pain 相似文献75.
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
76.
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
77.
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
78.
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
79.
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
80.