Special Theory of Relativity,Conceptual Change and History of Science     

Villani  Alberto  Arruda  Sergio M. 《Science & Education》1998,7(1):85-100

The problem of the learning of Special Theory of Relativity by secondary and college students is analysed. It is stressed that the results of the studies which attempted to evaluate students' learning are ambiguous and intriguing. Also the history of the emergence and acceptance of the theory by the scientific community itself at the beginning of the 20th century is analysed. Three fundamental steps are described: a) the publication of Lorentz's Transformation Equations, their interpretation in the context of the Electron Theory and their consequent acceptance by the scientific community; b) the presentation by Einstein of two postulates, namely the Relativity Principle and Einstein's Principle of the Invariance of the Speed of Light, and their partial acceptance; c) the rejection of the Electron Theory and the final acceptance of the Theory of Relativity simultaneously with the development of the General Theory of Relativity. The analogy between historical and learning processes provides some suggestions to improve the teaching of the theory.  相似文献   

The impact of individual consultation on the teaching of younger versus older faculty     

Sergio Piccinin  John-Patrick Moore 《International Journal for Academic Development》2013,18(2):123-134

This study examines the effect of age of instructor on student ratings of teaching performance after individual consultation. Instructors self-presented over an 11-year period at a large Canadian university teaching service, where each received one of three interventions. End of term student ratings of the teaching of younger and older instructors are compared before consultation, immediately post consultation, and 1–3 years after year of consultation. Younger faculty obtained significantly improved ratings immediately after consultation, while older faculty achieved significant rating increases 1–3 years post consultation. Results from an earlier study on the impact of individual consultation on teacher ratings are reevaluated using this larger sample of faculty. Generally, results in this analysis parallel the original research. Consultation produced changes in student ratings both immediately after consultation as well as longitudinally, thus confirming the utility of intervention in producing enduring pedagogical improvements. Control analyses ensured that improvements were a result of the interventions and not an artefact of time.  相似文献   

Irlen Colored Filters in the Classroom: A 1‐Year Follow‐Up     

Stuart J. Ritchie  Sergio Della Sala  Robert D. McIntosh 《Mind, Brain, and Education》2012,6(2):74-80

Colored filters are used to treat Irlen syndrome (IS), a controversial disorder posited to be the cause of a substantial proportion of reading difficulties. Previously, we found that Irlen colored filters do not produce any short‐term alleviation of reading difficulties in schoolchildren aged 7–12. Here, we tested whether colored filters show benefits with longer‐term use, in a subset of the original sample. We measured reading rate with and without filters in 18 children diagnosed with IS, who had been using the filters for 1 year, and compared the progression of their reading ability across the year against 10 poor‐reader control children. The Irlen‐treatment group did not read any faster when using their colored filter, and showed no disproportionate gain in reading progress across the year compared to controls. We conclude that Irlen filters do not benefit reading, even after 1 year of use.  相似文献   

Peer and neighborhood effects: Citation analysis using a spatial autoregressive model and pseudo-spatial data     

Sergio Copiello 《Journal of Informetrics》2019,13(1):238-254

Spatial analysis approaches have been long since adopted in citation studies. For instance, already in the early eighties, two works relied on input-output matrices to delve into citation transactions among journals (Noma, 1982; Price, 1981). However, the techniques meant to analyze spatial data have evolved since then, experiencing a major step change starting from the turn of the century or so. Here I aim to show that citation analysis may benefit from the development and latest improvements of spatial data analysis, primarily by borrowing the spatial autoregressive models commonly used to identify the occurrence of the so-called peer and neighborhood effects. I discuss features and potentialities of the suggested method using an Italian narrow academic sector as a test bed. The approach proves itself useful for identifying possible citation behavior and patterns. Especially, I delve into the relationships between citation frequency at author level and years of activity, references, references used by the closest peers, self-citations, number of co-authors, conference papers, and conference papers authored by the nearby researchers.  相似文献   

Is strength-training frequency a key factor to develop performance adaptations in young elite soccer players?     

Carlos Otero-Esquina  Óliver Gonzalo-Skok  Sergio Domínguez-Cobo  Hugo Sánchez 《European Journal of Sport Science》2017,17(10):1241-1251

The aim of this study was to analyse the effects of a combined strength-training programme (full-back squat, YoYo^TM leg curl, plyometrics and sled towing exercises) on performance in elite young soccer players and to examine the effects when this training programme was performed one or two days per week. Thirty-six male soccer players (U-17 to U-19) were recruited and assigned to experimental groups (EXP1: 1?s?w^?1; EXP2: 2?s?w^?1) or a control group (CON). Performance was assessed through a countermovement jump (CMJ) test (relative peak power [CMJ_PP] and CMJ height [CMJ_H]), a 20-m linear sprint test with split-times at 10-m, and a change of direction test (V-cut test) 1 week before starting the training programme and also 1 week after performing such training programme. Within-group analysis showed substantial improvements in CMJ variables (ES: 0.39–0.81) and COD (ES: 0.70 and 0.76) in EXP1 and EXP2, while EXP2 also showed substantial enhancements in all linear sprinting tests (ES: 0.43–0.52). Between-group analysis showed substantially greater improvements in CMJ variables (ES: 0.39–0.68) in experimental groups in comparison to CON. Furthermore, EXP2 achieved a substantial better performance in 20-m (ES: 0.48–0.64) than EXP1 and CON. Finally, EXP2 also showed greater enhancements in 10-m (ES: 0.50) and V-cut test (ES: 0.52) than EXP1. In conclusion, the combined strength-training programme improved jumping ability, independently of training frequency, though the achievement of two sessions per week also enhanced sprinting abilities (linear and COD) in young soccer players.  相似文献   

Presidential Wives: The Unacknowledged Legislators of the Race     

Sergio Rizzo 《Journal of American culture (Malden, Mass. : 2003)》1991,14(4):23-27

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Control of clock signals     

Marcello Farina  Sergio Bittanti  Lorenzo Galleani 《Journal of The Franklin Institute》2009,346(5):449-469

Precision and reliability of timescales are of importance in many situations, in particular in satellite navigation systems (i.e., Galileo system). Motivated by the necessity to improve the precision and the reliability of such clock signals, we have explored the possibility to exploit control theory in clock steering methods. First of all we provide a more robust theoretical framework for the analysis of the process. Two novel control algorithms are here proposed aiming to meet metrological specifications. Numerical simulations have been performed in order to evaluate the performances of the new control systems.  相似文献   

Addressing ontology-based question answering with collections of user queries     

Óscar Ferrández  Rubén Izquierdo  Sergio Ferrández  José Luis Vicedo 《Information processing & management》2009

This paper presents QACID an ontology-based Question Answering system applied to the CInema Domain. This system allows users to retrieve information from formal ontologies by using as input queries formulated in natural language. The original characteristic of QACID is the strategy used to fill the gap between users’ expressiveness and formal knowledge representation. This approach is based on collections of user queries and offers a simple adaptability to deal with multilingual capabilities, inter-domain portability and changes in user information requirements. All these capabilities permit developing Question Answering applications for actual users. This system has been developed and tested on the Spanish language and using an ontology modelling the cinema domain. The performance level achieved enables the use of the system in real environments.  相似文献   

The influence of serve characteristics on performance in men's and women's high-standard beach volleyball     

Buscà B  Moras G  Peña J  Rodríguez-Jiménez S 《Journal of sports sciences》2012,30(3):269-276

The precise influence of serve type and serve ball speed on beach volleyball performance is unclear. We examined the relationship between serve type and speed and their effectiveness during the 2008 Men's and Women's Open World Tour Tournament. Three hundred and seventy-eight and 375 serves performed by men and women respectively from the main draw tournament were analysed. Serve speed was recorded using a radar gun. Two expert observers recorded serve speed, serve mode, serve effectiveness and rally outcome. There was no relationship between serve speed and its effectiveness for men (r = -0.047, P > 0.05) and for women (r = -0.048, P > 0.05). However, there was a relationship between serve ball speed and its effectiveness both for men and women, when speed was categorised into three groups. There was a better balance between negative and positive outcomes at medium speeds for men and at low and high speeds for women. There was a relationship between ranking and serve ball speed only for women and between ranking and type of serve for both genders. There was no relationship between rally outcome and serve effectiveness. The combination of high ball speed and jump serve is characteristic of high ranking women but not of men.  相似文献   

Validity and reliability of a novel iPhone app for the measurement of barbell velocity and 1RM on the bench-press exercise     

Carlos Balsalobre-Fernández  David Marchante  Mario Muñoz-López  Sergio L. Jiménez 《Journal of sports sciences》2018,36(1):64-70

The purpose of this study was to analyse the validity and reliability of a novel iPhone app (named: PowerLift) for the measurement of mean velocity on the bench-press exercise. Additionally, the accuracy of the estimation of the 1-Repetition maximum (1RM) using the load–velocity relationship was tested. To do this, 10 powerlifters (Mean (SD): age = 26.5 ± 6.5 years; bench press 1RM · kg^?1 = 1.34 ± 0.25) completed an incremental test on the bench-press exercise with 5 different loads (75–100% 1RM), while the mean velocity of the barbell was registered using a linear transducer (LT) and Powerlift. Results showed a very high correlation between the LT and the app (r = 0.94, SEE = 0.028 m · s^?1) for the measurement of mean velocity. Bland–Altman plots (R² = 0.011) and intraclass correlation coefficient (ICC = 0.965) revealed a very high agreement between both devices. A systematic bias by which the app registered slightly higher values than the LT (P < 0.05; mean difference (SD) between instruments = 0.008 ± 0.03 m · s^?1). Finally, actual and estimated 1RM using the app were highly correlated (r = 0.98, mean difference (SD) = 5.5 ± 9.6 kg, P < 0.05). The app was found to be highly valid and reliable in comparison with a LT. These findings could have valuable practical applications for strength and conditioning coaches who wish to measure barbell velocity in the bench-press exercise.  相似文献