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991.
992.
The relationship between domestic professional tournament structure in women's tennis and the subsequent professional ranking success of a nation's female players is examined. The 2003 women's professional tennis tournament calendar provided the distribution of events in 33 countries. Criteria used to classify nations' success in women's professional tennis were as follows: number of players with Women's Tennis Association (WTA) points, number of players with Top 200 rankings, and the combined WTA ranking of a nation's Top 5 female players. Pearson product - moment correlations were performed between the number of tournaments and the three criteria. Considerable variation was observed in the number of events organized between nations (USA, n = 56; Thailand, n = 3). All countries had internationally ranked female players, and 24 nations had players ranked in the Top 200. Results revealed relationships between a nation's number of women's professional events and both that nation's number of professionally ranked players (r = 0.60; P < 0.01) and Top 200 players (r = 0.60; P < 0.01), as well as the combined ranking of their Top 5 players (r = -0.52; P < 0.01). While a similar association was found between the number of professional events and players ranked in the men's game, there was no significant correlation between events held and the combined standing of nations' best five ranked players. Governing bodies and national associations in tennis should consider the provision of professional, domestic competition as key to the development of female tennis players. 相似文献
993.
The aims of the present study were (1) to analyse the physical demands of top-class referees and (2) to compare their official FIFA fitness test results with physical performance during a match. The work rate profiles of 11 international referees were assessed during 12 competitive matches at the 2003 FIFA Under-17 World Cup and then analysed using a bi-dimensional photogrammetric video analysis system based on direct lineal transformation (DLT) algorithms. In the first 15 min of matches, the referees were more active, performing more high-intensity exercise (P < 0.01) than in the first 15 min of the second half. During the second half of matches, the referees covered a shorter distance (P < 0.01), spent more time standing still (P < 0.05), and covered less ground cruising (P < 0.05), sprinting (P < 0.05), and moving backwards (P < 0.001) than in the first half. Also in the second 45 min, the distance of referees from infringements increased (P < 0.05) in the left attacking zone of the filed. There was also a decrease (P < 0.05) in performance in the period following the most high-intensity activity, compared with the mean for the 90 min. Time spent performing high-intensity activities during a match was not related to performance in the 12-min run (r(2) = 0.30; P < 0.05), the 200-m sprint (r(2) = 0.05; P < 0.05), or the 50-m sprint (r(2) = 0.001; P < 0.05). The results of this study show that: (1) top-class referees experienced fatigue at different stages of the match, and (2) the typical field tests used by FIFA (two 50-m and 200-m sprints, followed by a 12-min run) are not correlated with match activities. 相似文献
994.
Vega Prez-Gracia Francisco García Lluis G. Pujades Ramn Gonzlez Drigo Daniel Di Capua 《Journal of Cultural Heritage》2008,9(1):89-96
This paper describes the ground-penetrating radar (GPR) survey carried out on the Roman theatre of Sagunto (Valencia, Spain) following recent restoration work in 1991. The structure has been substantially altered a number of times: it was remodelled during the Roman and Moorish periods, partially destroyed during the Peninsular War (1808–1814) and the Carlist War (1833–1839), and extensively modified during the 1930s and 1950s. Major reconstruction work was carried out in 1991 to convert the building into a working theatre. The GPR survey was performed to detect the possible effects of the 1991 remodelling on the historical remains and to identify the point of contact between the present-day modifications and the Roman remains. We took several on-site measurements of the wave velocity in the different materials in known areas to determine as accurately as possible the depth of the contact point. The velocity was calculated by measuring the depth in these areas and the two-way travel time of the wave. The measurements were taken from the walls and the tiers as the thicknesses of the materials were known in these areas. The recorded values were compared with the velocities reported by other authors and with the information from diffraction hyperbolas recorded in the radar data, which are caused by small objects inserted in the medium. We used these velocities to determine the exact point of contact between the Roman remains and the materials used in later restorations. The contact points cause the reflections that can be seen in the GPR data. The results also reveal considerable variations in the surface of the Roman tiers, which can be attributed to partial erosion in these areas caused mainly by water. 相似文献
995.
996.
Yu-Dong Zhang Suresh Chandra Satapathy David S. Guttery Juan Manuel Górriz Shui-Hua Wang 《Information processing & management》2021,58(2):102439
AimIn a pilot study to improve detection of malignant lesions in breast mammograms, we aimed to develop a new method called BDR-CNN-GCN, combining two advanced neural networks: (i) graph convolutional network (GCN); and (ii) convolutional neural network (CNN).MethodWe utilised a standard 8-layer CNN, then integrated two improvement techniques: (i) batch normalization (BN) and (ii) dropout (DO). Finally, we utilized rank-based stochastic pooling (RSP) to substitute the traditional max pooling. This resulted in BDR-CNN, which is a combination of CNN, BN, DO, and RSP. This BDR-CNN was hybridized with a two-layer GCN, and yielded our BDR-CNN-GCN model which was then utilized for analysis of breast mammograms as a 14-way data augmentation method.ResultsAs proof of concept, we ran our BDR-CNN-GCN algorithm 10 times on the breast mini-MIAS dataset (containing 322 mammographic images), achieving a sensitivity of 96.20±2.90%, a specificity of 96.00±2.31% and an accuracy of 96.10±1.60%.ConclusionOur BDR-CNN-GCN showed improved performance compared to five proposed neural network models and 15 state-of-the-art breast cancer detection approaches, proving to be an effective method for data augmentation and improved detection of malignant breast masses. 相似文献
997.
F. Javier Gómez-Patrocinio Camilla Mileto Lidia García-Soriano Fernando Vegas López-Manzanares 《文物保护研究》2020,65(8):450-464
ABSTRACT This article presents the study of the main phenomena of material weathering and structural damage that affect traditional architecture built in adobe, analysing the damage found in 553 case studies, representative of different technical varieties of adobe construction in Spain. The analysis methodology proposed in this text made it possible to quantify and identify the risks of damage appearing, establishing its impact and identifying its main mechanisms and causes. At the same time, the behaviour of adobe construction systems was further studied, observing how specific modifications in technique can promote or hinder deterioration and establishing the probable causes of the different responses to these phenomena. 相似文献
998.
Alberto Grao-Cruces David Sánchez-Oliva Carmen Padilla-Moledo Rocío Izquierdo-Gómez Verónica Cabanas-Sánchez Jose Castro-Piñero 《Journal of sports sciences》2020,38(7):780-786
ABSTRACTThe aims of this study were (i) to examine the sedentary time (ST) during different time periods [i.e., weekend, out-of-school weekdays hours, school hours, recess, physical education classes (PEC)] in children and adolescents; (ii) to identify 2-year longitudinal changes in the ST for these periods; and (iii) to examine if ST at baseline is associated with ST 2 years later. This was a 2-year follow-up study with 826 (51.9% boys) children and 678 (50.7% boys) adolescents. Accelerometers were used to assess ST. Students spent more than 60% of their weekend, out-of-school hours and school hours in ST. During these periods, girls and adolescents were more sedentary than boys and children, respectively (p < 0.05). Over 2-year follow-up, ST increased during the weekend, out-of-school hours, school hours and recess in all subgroups studied (p < 0.001). ST during PEC declined 2% per year in children (p < 0.001) but it increased in adolescents (p < 0.05). ST during the periods analysed at baseline was lowly associated with ST during these periods 2 years later (intraclass correlations from <0.001 to 0.364). Interventions in these settings may be adequate if the intention is to avoid ST increase in students. 相似文献
999.
F. Javier Núñez Carlos Galiano Alejandro Muñoz-López Pablo Floria 《Journal of sports sciences》2020,38(14):1624-1628
ABSTRACT The aims of this study were to compare the force profile of using a horizontal cylinder-shaped axis or a vertical cone-shaped axis to provide resistance in rotary inertia devices, and to report the evolution of kinetic and kinematic variables in experienced athletes during a half-squat exercise. Twenty-two healthy active men participated in the assessment of time, peak velocity, peak force, time to reach the peak force, average force, impulse, and range of movement, during a half-squat incremental test performed on conical inertial device (CP) and on cylinder inertial device (YY). The analysis showed that YY during CON-ECC phased generates substantial higher peak_force, mean_force, impulse, time, and a lower peak_velocity, than CP. We never obtained eccentric overload for peak_force or mean_force. CP offers less resistance to accelerate-decelerate the movement with respect to YY, we need checking whether eccentric overload it is being produced, and the impulse was the only kinetic variable that was able to discriminate between the inertias and devices. 相似文献
1000.
PROSPECTS - This Viewpoint argues that the debates about the future of education and the need to rethink the school model started long before the pandemic crisis. But the situation we are... 相似文献