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171.
This special issue contains articles describing XML retrieval approaches developed and evaluated during the second year of INEX, the evaluation initiative for XML retrieval. 相似文献
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All traumatic and overuse injuries occurring during an average period of 4 years (2002/09) in a group of 51 currently active road top-level cyclists were retrospectively registered through clinical interviews. Average age was 25.8 years. Average training and competition period was 28.3 ± 2.4 h a week. Only 8 cyclists (15.6%) were completely free from lesions during the period of study. The remaining 43 cyclists suffered a total of 112 lesions; however, 9 out of these were unrelated to their cycling practice. These 103 cycling-related injuries include 50 (48.5%) traumatic and 53 (51.5%) overuse injuries. Twenty-eight fractures were reported, the clavicle being the most frequently affected bone (11 cases). The 68.5% of overuse injuries were located in the lower limbs. Most overuse injuries (89.6%) occurred during the training period. According to the injury abbreviated scale (AIS), severe lesions were only found in 4 cases (8% of traumatic injuries). Overall injury rates were 0.50 per racer/year, 2.02 per studied racer, and 0.007 per 1000 km of training and competition. Active professional top-level cyclists are exposed to a high injury risk. According to the scarce previously published data the current study provides relevant information on the injury occurrence of still active top-level road cycling. 相似文献
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Abstract In soccer, critical match events like goal attempts can be preceded by periods of instability in the balance between the two teams' behaviours. Therefore, we determined periods of high variability in the distance between the teams' centroid positions longitudinally and laterally in an international-standard soccer match and evaluated corresponding match events. Position data were collected with AMISCO Pro?. Inter-team distance variability was calculated over a 3-s moving window. Out of the 242 match periods that exceeded the variability criterion, 51 were dead-ball situations. Match events identified through longitudinal inter-team distance primarily related to defending players moving forward-backward after a longitudinal pass. Match events identified through lateral inter-team distance mainly corresponded with defending players moving laterally following sideways passing. One of two goals and two of fourteen goal-attempts were preceded by a period of high variability. Together, periods of highly variable inter-team distance were associated with collective defensive actions and team reorganisation in dead-ball moments rather than goals or goal attempts. Inter-team dynamics quantified (mutual) reorganisation of the teams and marked teams' collective defensive ability to respond to attacking explorations. 相似文献
175.
This study examined the influence of the regression model and initial intensity of an incremental test on the relationship between the lactate threshold estimated by the maximal-deviation method and the endurance performance. Sixteen non-competitive, recreational female runners performed a discontinuous incremental treadmill test. The initial speed was set at 7 km · h?1, and increased every 3 min by 1 km · h?1 with a 30-s rest between the stages used for earlobe capillary blood sample collection. Lactate-speed data were fitted by an exponential-plus-constant and a third-order polynomial equation. The lactate threshold was determined for both regression equations, using all the coordinates, excluding the first and excluding the first and second initial points. Mean speed of a 10-km road race was the performance index (3.04 ± 0.22 m · s?1). The exponentially-derived lactate threshold had a higher correlation (0.98 ≤ r ≤ 0.99) and smaller standard error of estimate (SEE) (0.04 ≤ SEE ≤ 0.05 m · s?1) with performance than the polynomially-derived equivalent (0.83 ≤ r ≤ 0.89; 0.10 ≤ SEE ≤ 0.13 m · s?1). The exponential lactate threshold was greater than the polynomial equivalent (P < 0.05). The results suggest that the exponential lactate threshold is a valid performance index that is independent of the initial intensity of the incremental test and better than the polynomial equivalent. 相似文献
176.
Amparo Núñez Andrés Felipe Buill Pozuelo Joaquín Regot Marimón Andrés de Mesa Gisbert 《Journal of Cultural Heritage》2012,13(1):103-106
Different techniques and tools currently exist to generate three-dimensional models of small elements, buildings and cities. Apart from being easier to interpret than two-dimensional drawings, these models facilitate data necessary for reconstruction projects, preservation or rehabilitation of the architectural or archaeological heritage. Traditional surveying only enables us to obtain discrete information of the characteristic lines that define each surface, edge, slope change etc. whereas work with massive capture techniques allows us to obtain continuous points of the surfaces. Photogrammetry or laser scanning combined with conventional photography provides information of the building in addition to its geometry. We carried out a review of the different techniques showing the advantages and disadvantages of each technique as well as the information that can be obtained by applying these techniques to the survey of the great Gate of Antioch in the town of Aleppo, declared a World Heritage Site by UNESCO in 1986, in Syria. 相似文献
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Demet Yazilitas Jörgen Svensson Geert de Vries Sawitri Saharso 《Educational Research and Evaluation》2013,19(6):525-545
This article presents an overview of the recent literature on gendered patterns of academic choice in mathematics, science, and technology. It distinguishes in this literature micro-level, macro-level, and institutional explanations. Micro-level explanations focus primarily on psychological constructs, that is, variables at the level of the individual students. Macro-level explanations focus primarily on socioeconomic conditions and cultural understandings of gender roles. Institutional explanations focus on design characteristics of (national) education systems. After a presentation of these perspectives and of recent research progress that has been made, the authors critically discuss the lacunae that still exist in explaining cross-national variety, and provide suggestions for designing future research in this field. 相似文献
180.
Ruurd Taconis Lesley G.M. de Putter-Smits Steven Henry Perry J. den Brok Douwe Beijaard 《Educational Research and Evaluation》2013,19(4):383-400
Forming a science-oriented identity is considered a process underlying both interest and achievement in science education. A questionnaire is developed for describing “identities as learners” and evaluating their science orientedness. The instrument (k = 65) focuses on cognitive aspects. An internal coherence of .88 was found. Five subscales were defined that proved interrelated yet distinguishable. A pilot amongst 40 students from Dutch general secondary education showed that preferring science over non-science subjects and relatively high grades for sciences subjects were strongly correlated to science orientedness of the learner identity (rs = .65; p < .001). The results support the reliability and validity of the questionnaire but also point to the importance of identity as a central concept in studying science education. It is concluded that we made a promising step in constructing an instrument for monitoring the development of cognitive aspects of science-oriented identities during (innovative) science education. 相似文献