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141.
Stefan Vogt Yorck Olaf Schumacher Andreas Blum Kai Roecker Hans-Hermann Dickhuth Andreas Schmid 《Journal of sports sciences》2013,31(12):1299-1305
Abstract Until recently, the physiological demands of cycling competitions were mostly reflected by the measurement of heart rate and the indirect estimation of exercise intensity. The purpose of this case study was to illustrate the varying power output of a professional cyclist during flat and mountain stages of a Grand Tour (Giro d'Italia). Nine stage recordings of a cyclist of the 2005 Giro d'Italia were monitored using a mobile power measurement device (SRM Trainingssystem, Julich, Germany), which recorded direct power output and heart rate. Stages were categorized into flat (n = 5) and mountain stages (n = 4). Data were processed electronically, and the overall mean power in flat and mountain stages and maximal mean power for various durations were calculated. Mean power output was 132 W ± 26 (2.0 W · kg?1 ± 0.4) for the flat and 235 W ± 10 (3.5 W · kg?1 ± 0.1) for the mountain stages. Mountain stages showed higher maximal mean power (367 W) for longer durations (1800 s) than flat stages (239 W). Flat stages are characterized by a large variability of power output with short bursts of high power and long periods with reduced intensity of exercise, whereas mountain stages mostly require submaximal, constant power output over longer periods. 相似文献
142.
Giuseppe Bruno Emilio Esposito Andrea Genovese Kholekile L. Gwebu 《The Information Society》2013,29(1):16-28
Several composite indexes grouping several variables into a single figure have been proposed for measuring the digital divide. In this article, the authors analyze shortcomings of extant indexes. Using multivariate analysis tools, they show that in the definition of composite indexes it is possible to individuate a limited set of more influencing and significant variables. This finding suggests the possibility of replacing some redundant variables with other dimensions that include other aspects of the digital divide that are not considered in extant measures. 相似文献
143.
Rachel Duffy Andrew Fearne Sue Hornibrook Karise Hutchinson Andrea Reid 《International Journal of Information Management》2013
Given the crucial role of suppliers in collaborative supply chains, it is surprising that little attention has been paid to the nature and management of supplier relationships in the implementation of a retailer's Customer Relationship Management (CRM) strategy. To address this gap in the extant literature, the theory of organizational justice is used to explore the extent to which perceived fairness in buyer–supplier relationships supports or inhibits supplier engagement with the CRM process. The rationale is that suppliers who feel fairly treated by key retail customers are more likely to invest resources in the acquisition and use of data central to the retailer's CRM strategy. By empirically testing a conceptual model linking downstream CRM to upstream SRM, the results provide evidence to indicate that customer data use is significantly influenced by perceptions of fairness, particularly with respect to the distribution of rewards, and the transparency of decision-making processes. As a key criticism of CRM centers upon the failure of organizations to exploit the full potential of customer data, the results highlight the usefulness of understanding the relational linkages between buyers and suppliers and the consequential behavior of suppliers in terms of engagement with customer data vital to the success of retailers’ CRM strategies. 相似文献
144.
This paper examines how the relationship between firm value and patent-based indicators of inventive activity has changed over time. We use data from more than 33,000 mergers and acquisitions deals between 1985 and 2007, and distinguish between American (USPTO) and European (EPO) patents. Our results indicate that over time EPO patents have become the dominant indicator of innovative activity, while USPTO patents have no effect on firm value near the end of the sample period. The results are robust to controlling for citations and are especially strong for small firms, for firms operating in the drug and chemical industries, and when target and acquiring firms operate in different industries or countries. 相似文献
145.
Andrea Klindworth 《Research in Science Education》1993,23(1):156-164
Emotional responses from local community groups to the establishment of new industrial activities, involving toxic chemicals,
are common. The need for more public education about chemical hazards has often been stated. In the eastern suburbs of Melbourne,
PCBs have been stored since 1985, pending their destruction. Council approval for the siting of a pilot plant for their treatment
recently caused controversy. This paper presents an analysis of the situation, defines the knowledge needed by ordinary people
to participate effectively and rationally in decision making and discusses the acquisition of that knowledge in a community
setting. It is not the intention of the author to discuss the contribution that could be made through formal secondary education.
Specializations: primary science teacher education, computers in education, environmental education, social responsibility in science. 相似文献
146.
147.
Academic Functioning and Peer Influences: A Short‐Term Longitudinal Study of Network–Behavior Dynamics in Middle Adolescence 下载免费PDF全文
J. Ashwin Rambaran Andrea Hopmeyer David Schwartz Christian Steglich Daryaneh Badaly René Veenstra 《Child development》2017,88(2):523-543
In this study, the associations between peer effects and academic functioning in middle adolescence (N = 342; 14–15 years old; 48% male) were investigated longitudinally. Similarity in achievement (grade point averages) and unexplained absences (truancy) was explained by both peer selection and peer influence, net of acceptance, and connectedness. Friendships were formed and maintained when adolescents had low levels of achievement or high levels of truancy. Friends influenced one another to increase rather than decrease in achievement and truancy. Moreover, friends’ popularity moderated peer influences in truancy in reciprocal friendships but not in unilateral friendships, whereas friends’ acceptance moderated peer influences in achievement in both unilateral and reciprocal friendships. The findings illustrate the dynamic interplay between peer effects and academic functioning. 相似文献
148.
Martin Nekola Andrea Principi Michal Švarc Markéta Nekolová Deborah Smeaton 《Educational gerontology》2018,44(7):403-415
Adopting a longitudinal approach, this article examines downward occupational mobility (DOM) later in working life and its effects on job satisfaction and perceptions of working conditions of older workers in Europe. The main aim was to test whether the risk that workers will be negatively impacted and marginalized in the labor market due to demotion into lower quality jobs is offset by benefits. Based on an ordinal logistic regression of merged Survey of Health, Ageing and Retirement in Europe and English Longitudinal Study of Ageing datasets, the study found a positive significant impact of DOM on overall job satisfaction. Moreover, DOM was associated with a statistically significant reduction in workload pressure, although it did increase physical work demand. This article adds to the literature on marginalization of workers with indications that the lower income and status associated with DOM at older ages may have offsetting benefits. 相似文献
149.
Poetry 总被引:1,自引:0,他引:1
150.
Jean-Luc Gurtner Alida Gulfi Philippe A. Genoud Bernardo de Rocha Trindade Jér?me Schumacher 《European Journal of Psychology of Education - EJPE》2012,27(2):213-225
In Germany, Austria and Switzerland, the majority of 15?C19-year olds follow vocational education programmes within a dual-track system, spending most of their time in a company and going to school only 1?day each week. With their separate aims, content and sociological organisation, the company and the school can be considered as two distinct contexts within which apprentices have to acquire the various skills and competencies of their future occupation. In this paper, the development of apprentices?? learning intentions and motivation to learn, subjective competence, perceived utility of what is learned and estimated learning place attractiveness (study 1) as well as their readiness to seek help in these different contexts over the year of training (study 2) is analysed using both longitudinal and cross-sectional data. The findings show significant differences in apprentices?? motivation, their beliefs and their readiness to seek help in the different contexts throughout the training. Moderate (cross-different contexts, same time) as well as transcontextual (different contexts, different times) influences can also be seen. These results emphasise the importance of a careful delimitation of contexts when studying the impact of contextual factors on learners?? motivation and behaviours; they also suggest that motivation within one of these contexts can indirectly affect the learner??s motivation within another of these contexts. It is therefore likely that, by using these various dynamics appropriately, educators might temporarily sustain learners?? motivation in an unappreciated context by having recourse to a better accepted one. 相似文献