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151.
在高层建筑深基坑支护各种方案中,通常土钉支护费用最低,当深基坑土质条件较差,如沿海地区淤泥质土层,含水量较大,基坑垂直支护面难以成型,难以采用土钉支护方案,引用钢板桩支护原理,本文采用25号槽钢与土钉组合深基坑支护方案,解决土钉在软土中应用不足和发挥槽钢封面的特点,成功解决软土地区土钉支护问题,由于槽钢可以全部回收重复使用,该支护方案造价较低,经济效益较好。  相似文献   
152.
Although communication skills in English are important for both their career prospects and the success of their overall study experience, many international students find their spoken English a barrier to employment after graduation. In this paper, we draw on longitudinal interview data from international postgraduates to investigate the individual and social factors that impacted on the development of their speaking skills as they studied in Australia. Our findings suggest that, despite high levels of motivation to improve, they received little instruction in such skills on their English for Academic Purposes programs and had little access to them in the community. We argue that for compelling moral as well as economic reasons universities urgently need to address these issues through both instruction and social integration initiatives if they are to safeguard their lucrative but vulnerable overseas markets.  相似文献   
153.
A fault diagnosis model is proposed based on fuzzy support vector machine (FSVM) combined with fuzzy clustering (FC).Considering the relationship between the sample point and non-self class,FC algorithm is applied to generate fuzzy memberships.In the algorithm,sample weights based on a distribution density function of data point and genetic algorithm (GA) are introduced to enhance the performance of FC.Then a multi-class FSVM with radial basis function kernel is established according to directed acyclic graph algorithm,the penalty factor and kernel parameter of which are optimized by GA.Finally,the model is executed for multi-class fault diagnosis of rolling element bearings.The results show that the presented model achieves high performances both in identifying fault types and fault degrees.The performance comparisons of the presented model with SVM and distance-based FSVM for noisy case demonstrate the capacity of dealing with noise and generalization.  相似文献   
154.
《Sport Management Review》2019,22(5):640-651
In this paper, the authors empirically analyze the influence of the gender of the coach on team performance in women’s soccer leagues. Moreover, the authors examine the role of initial experience of coaches (as professional players) as an attribute that converges with gender diversity and influence performance. The sample includes the top divisions in France, Germany, and Norway from 2004 to 2017. The results from the regression model show that the gender of the coach is not a significant determinant of team performance (points per game). In addition, the initial experience of coaches does not alter the results. Therefore, managerial decisions of clubs with regard to the employment of coaches should not rely on gender.  相似文献   
155.
运用文献资料法、调查法和逻辑分析法,对女性私人健身教练从业限制因素进行研究。利用访谈和问卷调查获得的数据,构建了女性私教从业限制因素的结构模型,并采用验证性因素分析对模型进行检验。结果显示:限制女性私教从业的因素主要包括个人限制因素、人际限制因素和企业限制因素,构建的三因素结构模型各项指标拟合度良好,结构稳定,可以为促进女性私人健身教练从业提供参考。进而从三个因素的角度,提出促进女性私教从业的建议,包括女性私教合理规划个人职业生涯,坚定从业信念;家人、同伴转变观念,提升女性私教的社会支持;健身企业切实履行对员工的社会责任,增强女性私教的工作满意度和企业认同感。  相似文献   
156.
The present study aimed to investigate pre-sleep behaviours (including evening electronic device use) and sleep quantity in well-trained athletes. Seventy well-trained athletes (44 females, 26 males) aged 21 ± 4 y from a range of team and individual sports were asked to complete an online sleep diary for 7 days. The sleep diary included questions about pre-sleep behaviours (e.g. napping, caffeine intake), electronic device use in the 2 h prior to bedtime (e.g. type of device and duration of use) and sleep (e.g. time in bed, sleep onset latency). On average, athletes spent 8:20 ± 1:21 h in bed each night. Associations between age, time in bed and sleepiness suggested that younger athletes spent more time in bed (= -0.05, p = 0.001) but felt sleepier (r = -0.32, p < 0.01) than older athletes. On average, athletes mostly used electronic devices for 0–30 min prior to sleep. The use of multiple devices in the evening was associated with more perceived difficulty in falling asleep (= 0.22, p = 0.03), but no associations existed with other sleep variables. In summary, younger athletes may require later start times or improved sleep quality to resolve excessive sleepiness.  相似文献   
157.
我国多数男生引体向上得"零"分,使上肢力量测评出现"地板效应"。采用量化研究和质性研究两种范式提高研究效度。量化研究对学生体质与健康调研数据和监测数据进行方差分析、多重比较和回归分析,结果表明:(1)每5~10年,男生的握力、体重、身高、BMI、引体向上均值差异显著;(2)年龄、握力、体重、身高、BMI分别显著预测引体向上成绩,体重和握力是影响我国男生引体向上成绩的主要影响因素。质性研究结果表明,引体向上"零"分主要有四个方面的原因:体重增长难挡,力量增长受限,个体认知偏差,社会支持薄弱。结论:我国男生引体向上"零"分的首要原因是体重增长较快,其次,主要肌群绝对力量和耐力增长不足,男生对引体向上的认知有偏差,学校、家长、社会支持较弱;借助政策控制体重、发展肌力、完善测评标准、促进男生积极练习引体向上十分重要。  相似文献   
158.
有规律的体育锻炼对人们的身心健康具有积极的促进作用,而社会支持是影响锻炼行为的重要相关因素。因此本研究的目的在于编制和检验锻炼社会支持量表。通过结合现有研究文献和质性研究,确立了初测量表,并通过两轮定量研究,应用探索性和验证性因子分析,信度分析以及校标效度检验对该量表进行了标准化的信效度检验。结果表明锻炼社会支持量表由4个因子构成,即情感性支持、信息性支持、工具性支持、同伴性支持,共24个条目。统计分析显示,量表具有良好的结构效度、内部一致性、重测信度和校标效度。锻炼社会支持量表符合我国文化背景,可以作为在中国人群中进行锻炼社会支持测量的工具。  相似文献   
159.
A strong moral reason for prohibiting doping in sport is to be found in the bad choices that would be faced by clean athletes in a sporting world that tolerated doping. The case against doping is not, however, to be grounded in the concept of coercion. Instead, it is grounded in a general duty of sport to afford fair opportunity to the goods that are distinctively within sport's sphere of control. The moral reason to prohibit doping need not be balanced against any autonomy claim of athletes who would prefer to dope because, upon closer examination, such claims have no force. The moral reason to prohibit doping does, however, need to be balanced against the enforcement costs imposed on all athletes by effective prohibition.  相似文献   
160.
Purposes: This study applies the self-determination theory (SDT) to test the hypothesized relationships among perceived autonomy support from parents, physical education (PE) teachers, and peers, the fulfilment of psychological needs (i.e., autonomy, competence, and relatedness), autonomous motivation, and leisure-time physical activity of Chinese adolescents. Method: There are 255 grade six to eight student participants from four middle schools around Shanghai, China included in this study. An accelerometer was used to measure the moderate-to-vigorous physical activity (MVPA). The participants completed the questionnaires regarding SDT variables. The structural equation modelling was applied to examine the hypothesized relationships among the study variables. Results: The model of hypothesized relationships demonstrated a good fit with the data [X2?=?20.84, df?=?9, P?=?.01; CFI?=?0.98; IFI?=?0.98; SRMR?=?0.04; RMSEA?=?0.05]. The findings revealed that autonomy support from parents, PE teachers, and peers foster social conditions in which the three basic psychological needs can be met. In turn, autonomy, competence, and relatedness are positively associated with autonomous motivation for MVPA. The autonomous motivation positively relates to the MVPA time of adolescents. The three psychological needs partially mediate the influence of autonomy support from parents (β?=?0.18, P?<?.01; Bootstrap 95% CI?=?0.06–0.33) and teachers (β?=?0.17, P?<?.01; Bootstrap 95% CI?=?0.03–0.26) in the autonomous motivation. Conclusion: In conclusion, these findings support the applicability of SDT in understanding and promoting physical activity of Chinese adolescents.  相似文献   
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