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981.
982.
Luciano Rossi Rafael J.P. Damaceno Igor L. Freire Etelvino J.H. Bechara Jesús P. Mena-Chalco 《Journal of Informetrics》2018,12(4):1042-1058
Academic genealogy aims to structure and analyze the mentoring relationships between advisor and advisee. The representation of this structure results in academic genealogy graphs. For the analysis and characterization of these graphs, we present a set of metrics and their corresponding mirror metrics that capture the characteristics of its topological structure and represent them as quantitative attributes. The metrics of fecundity, fertility, descendants, cousins, generations, and relationships consider the descendants of the academics represented in the graph. The mirror metric of these topological metrics considers the ascendancy of academics. Individually, the metrics have strong semantic intuition and define characteristics regarding the performance in the mentoring of an academic. Together, the metrics are useful for the identification, characterization, and classification of communities and their members. The genealogical data available through the platforms of the Mathematics Genealogy Project and the Academic Family Tree were used as case studies. Two hundred thirteen thousand and 675,000 academic records were obtained for each project. We analyze the capacity of characterization of the metrics using the structuring of a similarity graph and through the distribution of the nodes in principal components. We observed that the set of metrics is capable of capturing the configuration pattern existing in genealogy graphs independently of its scale. 相似文献
983.
Moisés Prieto 《Media History》2013,19(2):192-207
Between General Franco's agony (October/November 1975) and the constitution's approval (December 1978), European media reported intensively about the democratisation process in Spain. The present paper deals with its examination through the Radio della Svizzera di lingua italiana broadcasts. As the only Swiss Italian-speaking broadcaster, it tried to provide in-depth information and opinion on a country whose solid ties with Switzerland were based on economy, migration and tourism. The study of this non-commercial radio allows us to determine the way the democratisation was approached and portrayed for a Swiss audience and offers a genuine case for transnational historical research. 相似文献
984.
Ágnes Gulyás 《媒体管理杂志》2013,15(2):74-81
Abstract Entrepreneurship theory complements established approaches to media management research with an alternative frame for viewing media ownership and the media's capacity for content diversity. Established entrepreneurship metrics were applied to media industries in the United States. All media sectors experienced varying rates in the second half of the last century; by the turn of the new century, nearly all were more entrepreneurial than any other U.S. service or manufacturing industry. 相似文献
985.
986.
987.
Patricia Pérez-Hornero José Pablo Arias-Nicolás Antonio A. Pulgarín Antonio Pulgarín 《Journal of Informetrics》2013,7(1):1-9
Our aim deals with appraising the annual impact calculation of journals belonging to the JCR, in terms of the expected citation (with or without selfcitations) by published paper in a range of k-years. A Bayesian approach to the problem, should reflect not only the current prestige of a journal, but also taking into account its recent trajectory. In this wide context, credibility theory becomes an adequate mechanism deciding whether journal's impact factor calculation to be more or less plausible. Under prior belief that journal quality is determined by its impact factor, we model the citation-quality process by choosing a conjugated family of the exponential class in order to obtain a net impact credibility formula. Proposed weighting schema produces the effect of smoothing out any sudden increases or decreases in the year-by-year impact factor. 相似文献
988.
989.
LoI¨c Damm Daniel Low Andrea Richardson James Clarke Matt Carré Sharon Dixon 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(4):389-402
The interaction between footwear and surfaces influences the forces experienced by tennis players. The purpose of this study was to investigate traction demand and kinematic adaptation during tennis-specific movements with changes in traction characteristics of surfaces. We hypothesised that players would increase the utilised coefficient of friction (horizontal to vertical ground reaction force ratio) when the shoe surface combination had a high coefficient of friction and flex their knee after contact to facilitate braking. Eight participants performed two separate movements, side jump out of stance and running forehand. Ground reaction force was measured and three-dimensional kinematic data were recorded. Clay surface and cushioned acrylic hard court (low vs. high shoe–surface friction) were used. The peak utilised coefficient of friction was greater on clay than the hard court. The knee was less flexed at impact on clay ( ? 5.6 ± 10.2°) and at peak flexion ( ? 13.1 ± 12.0°) during the running forehand. Our results indicate that tennis players adapt the level of utilised friction according to the characteristics of the surface, and this adaptation favours sliding on the low friction surface. Less knee flexion facilitates sliding on clay, whereas greater knee flexion contributes to braking on the hard court. 相似文献
990.
Gautier Zunquin Denis Theunynck Bruno Sesboüé Pierre Arhan Dominique Bouglé 《Journal of sports sciences》2013,31(4):315-318
Abstract In this study, we examined fat oxidation rates during exercise in obese pubescent boys. Three groups of pubescent boys (16 pre-pubescent, Tanner's stage I; 16 pubescent, Tanner's stage III; and 14 post-pubescent, Tanner's stage V) performed a graded test on a leg cycle ergometer. The first step of the test was fixed at 30 W and power was gradually increased by 20 W every 3.5 min. Oxygen consumption ([Vdot]O2) and carbon dioxide production ([Vdot]CO2) were determined as the means of measurements during the last 30 s of each step, which allowed us to calculate fat oxidation rates versus exercise intensity. Between 20 and 50% of peak oxygen consumption ([Vdot]O2peak), fat oxidation rate in relative values (mg · min?1 · kg FFM?1) decreased continuously with pubertal development. In the same way, the maximum rate of fat oxidation occurred at a lower percentage of [Vdot]O2peak (pre-pubescent: 49.47 ± 1.62%; pubescent: 47.43 ± 1.26%; post-pubescent: 45.00 ± 0.97%). Our results confirm that puberty is responsible for a decrease in fat free mass capacities to use fat during exercise. The results suggest that post-pubescent obese boys need to practise physical activity at a lower intensity than pre-pubescent boys to enhance lipolysis and diminish adipose tissue and the consequences of obesity. 相似文献