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11.
In this article, we focus on Chinese word segmentation by systematically incorporating non-local information based on latent variables and word-level features. Differing from previous work which captures non-local information by using semi-Markov models, we propose an alternative method for modeling non-local information: a latent variable word segmenter employing word-level features. In order to reduce computational complexity of learning non-local information, we further present an improved online training method, which can arrive the same objective optimum with a significantly accelerated training speed. We find that the proposed method can help the learning of long range dependencies and improve the segmentation quality of long words (for example, complicated named entities). Experimental results demonstrate that the proposed method is effective. With this improvement, evaluations on the data of the second SIGHAN CWS bakeoff show that our system is competitive with the state-of-the-art systems.  相似文献   
12.
In order to design and predict the dechlorination processes for remediating the halogenated aromatic compounds in the biobarrier system applied in situ,an anaerobic continuous-flow column was set up with the introduction of an enriched 2,4,6-trichlorophenol(TCP) reductive dechlorinating consortium.The fates of TCP and its metabolites were simulated according to the first-order sequential dechlorination kinetic model.The enriched TCP anaerobic dechlorinating consortium dechlorinated 100 μmol/L TCP to 4-chlorophenol(4-CP) via 2,4-dichlorophenol(DCP) in 10 d.The consortium was predominated with the phylum of Firmicutes and Bacteroidetes,based on the PCRdenaturing gradient gel electrophoresis(DGGE) analysis.After the consortium was applied to the column,the experimental data in the steady state were fitted by the least square method,and the first-order dechlorination kinetic constants from TCP to 2,4-DCP,from 2,4-DCP to 4-CP and from 4-CP to phenol,were 1.58 d-1,2.23 d-1 and 0.206 d-1,respectively.According to the fitting results,the required biobarrier width for the complete remediation of TCP,2,4DCP and 4-CP were 126 cm,130 cm and 689 cm,respectively.The dechlorination/degradation of 4-CP must be increased when the technology is applied to the real site.  相似文献   
13.
Youth athletes are known to be at high risk of musculoskeletal (MSK) injuries. Children in developed countries are increasingly adopting a sedentary lifestyle. Although some risk factors related to sports activities have been reported, the effect of lifestyle (i.e. screen time behaviour) on MSK pain in youth athletes is not well known. This study aimed to examine the association of game playing and TV viewing with MSK pain among youth athletes. A self-administered questionnaire was mailed to youth athletes belonging to the Miyagi Amateur Sports Association. The final study population included 6,143 youth athletes (male, 71.1%; age range, 6–15 years). Multiple logistic regression analysis was used to examine the association of game playing and TV viewing behaviour with MSK pain. The point prevalence of MSK pain was 25.5%. The longest category of game playing time (≥3 h) was significantly associated with MSK pain as compared with the shortest category (<1 h) (odds ratio, 1.39; 95% confidence interval, 1.12–1.73, p = 0.003). There was no significant association between TV viewing time and MSK pain. These results suggest that game playing time might be an associated factor for MSK pain among youth athletes.  相似文献   
14.
ABSTRACT

The purpose of this study was to investigate the effects of slope on three-dimensional running kinematics at high speed. Thirteen male sprinters ran at high speed (7.5 m/s) on a motorised treadmill in each a level and a 5.0% slope condition. Three-dimensional motion analysis was conducted to compare centre of mass (CoM) energetics, pelvis segment and lower limb joints kinematics. We found that contact time was not affected by the slope, whereas flight time and step length were significantly shorter in uphill compared to level running. Uphill running reduced negative CoM work and increased positive CoM work compared to level running. Ankle, knee and hip joints were more flexed at initial ground contact, but only the knee was more extended at the end of stance in uphill compared to level running. Additionally, the hip joint was more abducted, and the free leg side of the pelvis was more elevated at the end of stance in uphill running. Our results demonstrate that joint motion must be developed from a more flexed/adducted position at initial contact through a greater range of motion compared to level running in order to meet the greater positive CoM work requirements in uphill running at high speed.  相似文献   
15.
Accurate measurement of head volume is indispensable for precise assessments of body composition determined by hydrostatic weighing without head submersion. The purpose of this study was to establish a prediction equation for head volume measured by the immersion method from multiple regression analysis using head parameters (head circumference, head length, head breadth, neck girth and head thickness) as independent variables. The participants were 106 Japanese young adults (55 males and 51 females) aged 17?–?27 years. Intra-class correlation coefficients (ICCs) for each head parameter and head volume in males and females were very high (ICC = 0.993?–?0.999, 0.992?–?0.998). Head circumference was closely related to head volume measured by the immersion method (r = 0.719, 0.861, P <?0.05), and was the most important parameter for the prediction equation in both sexes. Head breadth was related poorly (r = 0.475, 0.500, P <?0.05) and showed a small individual difference. It was, therefore, excluded from the independent variables. The prediction equation for males was predicted head volume = 122.10X 1 + 106.19X 3 + 37.16X 4 - 89.46X 5 - 4754.93, R = 0.909, SEE = 121.75?ml, and that for females was predicted head volume = 213.83X 1 + 45.24X 3 + 36.85X 4 - 74.34X 5 - 8912.43, R = 0.913, SEE = 136.26?ml (where X 1 = head circumference, X 3 = head length, X 4 = neck girth, X 5 = head thickness, and SEE = standard error of the estimate). The limits of agreement for predicted and measured head volume were –?234.5 to 234.1?ml for males, and ??261.0 to 261.0?ml for females. In cross-validation groups of both sexes, there were no significant differences between measured head volume and predicted head volume. The correlation coefficients between measured head volume and predicted head volume in males and females were 0.894 and 0.908, respectively. The predicted head volume from prediction equations was considered to have high reliability and validity.  相似文献   
16.
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