Effects of mat characteristics on plantar pressure patterns and perceived mat properties during landing in gymnastics     

Pedro Pérez-Soriano  Salvador Llana-Belloch  Gaspar Morey-Klapsing  Jose Antonio Perez-Turpin  Juan Manuel Cortell-Tormo 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(4):245-257

Shock absorption and stability during landings is provided by both, gymnast ability and mat properties. The aims of this study were to determine the influence of different mat constructions on their energy absorption and stability capabilities, and to analyse how these properties affect gymnast's plantar pressures as well as subjective mat perception during landing. Six mats were tested using a standard mechanical drop test. In addition, plantar pressures and subjective perception during landing were obtained from 15 expert gymnasts. The different mats influenced plantar pressures and gymnasts' subjective perception during landing of gymnasts. Significant correlations between plantar pressures at the medial metatarsal and lateral metatarsal zones of the gymnasts' feet with the different shock absorption characteristics of the mats were found. However, subjective perception tests were not able to discriminate mat functionality between the six mats as no significant correlations between the mechanical mat properties with the subjective perception of these properties were found. This study demonstrated that plantar pressures are a useful tool for discriminating different landing mats. Using similar approaches, ideally including kinematics as well, could help us in our understanding about the influences of different mats upon gymnast-mat interaction.  相似文献   

Teaching Modern Chemistry through ‘Recurrent Historical Teaching Models’     

José Antonio Chamizo 《Science & Education》2007,16(2):197-216

Today there are little more of 3 million chemist all over the world producing about 800,000 papers a year. They produce new substances – from some hundreds in 1800 to about 20 million now – the vast majority artificial. This rate is growing quite fast. Once the majority of chemistry teachers all over the world used textbooks as the main (sometimes the only) source of information, we became, without wanting to... history teachers! If ‘scientific literacy’ is the aim of science lessons in school, it is much more than the literacy now developed in science classrooms. It must include an understanding of the nature and process by which scientific activities are carried out. Recognition of the exponentially chemistry knowledge growth and the incompleteness of the current chemistry textbooks are thus intimately related to recognition of the need for recurrent historical teaching models.  相似文献   

Primary pre-service teachers’ skills in planning a guided scientific inquiry     

Antonio García-Carmona  Ana M. Criado  Marta Cruz-Guzmán 《Research in Science Education》2017,47(5):989-1010

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Perceptual learning transfer in an appetitive Pavlovian task     

Antonio A. Artigas  Jose Prados 《Learning & behavior》2017,45(2):115-123

In two experiments, rats were given intermixed or blocked preexposure to two similar compound stimuli, AX and BX. Following preexposure, conditioning trials took place in which AX (Experiment 1) or a novel compound stimulus NX (Experiment 2) was paired with a food-unconditioned stimulus in an appetitive Pavlovian preparation. Animals that were given alternated preexposure showed lower generalization from AX to BX (Experiment 1) and from NX to a new compound, ZX (Experiment 2), than animals that were given blocked preexposure, a perceptual learning and a perceptual learning transfer effect, respectively.  相似文献   

Multi-objective optimization design of bridge piers with hybrid heuristic algorithms     

Francisco J. Martinez-Martin  Fernando Gonzalez-Vidosa  Antonio Hospitaler  Víctor Yepes 《浙江大学学报(A卷英文版)》2012,13(6):420-432

This paper describes one approach to the design of reinforced concrete (RC) bridge piers, using a three-hybrid multi-objective simulated annealing (SA) algorithm with a neighborhood move based on the mutation operator from the genetic algorithms (GAs), namely MOSAMO1, MOSAMO2 and MOSAMO3. The procedure is applied to three objective functions: the economic cost, the reinforcing steel congestion and the embedded CO₂ emissions. Additional results for a random walk and a descent local search multi-objective algorithm are presented. The evaluation of solutions follows the Spanish Code for structural concrete. The methodology was applied to a typical bridge pier of 23.97 m in height. This example involved 110 design variables. Results indicate that algorithm MOSAMO2 outperforms other algorithms regarding the definition of Pareto fronts. Further, the proposed procedure will help structural engineers to enhance their bridge pier designs.  相似文献   

A survey of approaches for ranking on the web of data     

Antonio J. Roa-Valverde  Miguel-Angel Sicilia 《Information Retrieval》2014,17(4):295-325

Ranking information resources is a task that usually happens within more complex workflows and that typically occurs in any form of information retrieval, being commonly implemented by Web search engines. By filtering and rating data, ranking strategies guide the navigation of users when exploring large volumes of information items. There exist a considerable number of ranking algorithms that follow different approaches focusing on different aspects of the complex nature of the problem, and reflecting the variety of strategies that are possible to apply. With the growth of the web of linked data, a new problem space for ranking algorithms has emerged, as the nature of the information items to be ranked is very different from the case of Web pages. As a consequence, existing ranking algorithms have been adapted to the case of Linked Data and some specific strategies have started to be proposed and implemented. Researchers and organizations deploying Linked Data solutions thus require an understanding of the applicability, characteristics and state of evaluation of ranking strategies and algorithms as applied to Linked Data. We present a classification that formalizes and contextualizes under a common terminology the problem of ranking Linked Data. In addition, an analysis and contrast of the similarities, differences and applicability of the different approaches is provided. We aim this work to be useful when comparing different approaches to ranking Linked Data and when implementing new algorithms.  相似文献   

Telenovela reception in rural Brazil: gendered readings and sexual mores     

Antonio C. La Pastina 《Critical Studies in Media Communication》2013,30(2):162-181

In The Cattle King, a Brazilian telenovela, melodramatic elements of class ascension, love and betrayal, adultery, and pre‐marital sex played a central role in the lives of the main characters. This ethnographic study of viewers in Macambira, a small rural community in the backlands of northeast Brazil, discusses how these rural viewers appropriated telenovelas in their daily lives and how the meanings assigned to the texts were interpreted according to their own values and beliefs about gender roles, relationships, and sexuality. I argue that the geographical isolation and the local patriarchal culture mediated the process of reception, interpretation, and appropriation of telenovelas. The isolation in which Macambira is located in relation to the urban representations in the telenovela narratives intensified the perceived gap between the local patriarchal culture and the urban reality constructed in the television text.  相似文献   

Second Chance Programmes: a response to educational needs in compulsory education     

Antonio Sánchez Asín  José Luís Boix Peinado 《欧洲特需教育杂志》2013,28(3):179-188

This paper asks whether the integrated training provision currently offered through the different Spanish Second Chance Programmes (SCPs) constitutes a valid response to the educational needs and deficits known to exist among those young people who do not satisfactorily complete the Compulsory Secondary Education stage (ESO). The objectives of the current Social Guarantee Programmes (SGPs) are examined, as are the characteristics of the young people who participate in them. The Programmes of Initial Vocational Qualification (PCPI) envisaged in the most recent educational legislation are also discussed. Having identified the key factors which the empirical studies suggest influence the effectiveness of these programmes in addressing the educational needs and training deficiencies of the young people involved, a number of proposals are presented in connection with the training needs of teaching staff. The paper concludes with a number of proposals for improving the educational response to the challenges that the new perspectives and expectations raise for the development of a system of inclusive education to overcome the education deficits of the young people concerned.  相似文献   

Spanish Secondary-School Science Teachers’ Beliefs About Science-Technology-Society (STS) Issues     

Ángel Vázquez-Alonso  Antonio García-Carmona  María Antonia Manassero-Mas  Antoni Bennàssar-Roig 《Science & Education》2013,22(5):1191-1218

This study analyzes the beliefs about science-technology-society, and other Nature of Science (NOS) themes, of a large sample (613) of Spanish pre- and in-service secondary education teachers through their responses to 30 items of the Questionnaire of Opinions on Science, Technology and Society. The data were processed by means of a multiple response model to generate the belief indices used as the bases for subsequent quantitative and qualitative analyses. Other studies have reported a negative profile of teachers’ understanding in this area, but the diagnosis emerging from the present work is more complex. There was a mix of appropriate beliefs coexisting with others that are inappropriate on the topics analyzed. The overall assessment, however, is negative since clearly teachers need to have a better understanding of these questions. There were scant differences between the pre- and in-service teachers, and hence no decisive evidence that the practice of teaching contributes to improving the in-service teachers’ understanding. These results suggest there is an urgent need to bring the initial and continuing education of science teachers up to date to improve their understanding of these topics of science curricula, and thus improve the teaching of science.  相似文献   

Data-Division–Specific Robustness and Power of Randomization Tests for ABAB Designs     

Rumen Manolov  Antonio Solanas  Isis Bulté  Patrick Onghena 《Journal of Experimental Education》2013,81(2):191-214

This study deals with the statistical properties of a randomization test applied to an ABAB design in cases where the desirable random assignment of the points of change in phase is not possible. To obtain information about each possible data division, the authors carried out a conditional Monte Carlo simulation with 100,000 samples for each systematically chosen triplet. The authors studied robustness and power under several experimental conditions—different autocorrelation levels and different effect sizes as well as different phase lengths determined by the points of change. Type I error rates were distorted by the presence of autocorrelation for the majority of data divisions. The authors obtained satisfactory Type II error rates only for large treatment effects. The relation between the lengths of the four phases appeared to be an important factor for the robustness and power of the randomization test.  相似文献