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221.
Unlike Web hyperlink data, Web traffic data have not yet been the focus of considerable study in Webometrics research. The relationships between Web traffic data and academic/business performance measures have not been as firmly established as the relationships between Web hyperlink data and such performance measures. Although various traffic data sources exist, few studies have examined and compared their relative merits. We carried out a study that aimed to address this lack. We selected groups of universities and businesses from the U.S. and China and collected their Web traffic data from three sources: Alexa Internet, Google Trends for Websites, and Compete. We found significant correlations between Web traffic data and organizational performance measures, specifically academic quality for universities and financial variables for businesses. We also examined the characteristics of the three data sources and compared their usefulness. We found that Alexa Internet outperformed the others. 相似文献
222.
目的:探讨老年高血压患者24小时动态脉压指数与胱抑素C(CysC)、颈动脉内膜厚度(IMT,intima-media thickness)的相关性。方法:选择桂林市第二人民医院老年科2012年6月至2013年6月住院80例老年高血压患者,年龄71.30±3.90岁,入院后行24小时动态血压监测,计算24小时动态脉压指数=24小时动态脉压/24小时平均收缩压,取中位数0.51分组,24h PPI〉0.51为A组,24h PPI〈0.51为B组,分组分别测定血清胱抑素C(CysC),彩色多普勒测定颈动脉IMT。结果:A组CysC、颈动脉IMT均明显高于B组的高血压病患者,差异有统计学意义(P〈0.05)。结论:老年高血压患者24小时动态脉压指数与胱抑素C、颈动脉IMT正相关。 相似文献
223.
刘志辉 《辽宁科技学院学报》2013,(3)
文章介绍了炼铁厂环保除尘设备离线式脉冲布袋除尘器设备工艺原理。针对离线式脉冲布袋除尘器故障产生的原因,提出解决处理离线式脉冲布袋除尘器故障的方法及改进措施,为快速排除故障,降低设备停机率,减轻职工的劳动强度提供了依据。 相似文献
224.
PtNi/C nanoparticles with different atomic ratios of Pt/Ni were produced in pulse microwave assisted polyol process. Transmission electron microscopy(TEM) images show uniform morphology. X-ray diffraction(XRD) pattern plus energy dispersive X-ray(EDX) spectroscopy suggests pure composition. Cyclic voltammogram study reveals that PtNi/C nanoparticles synthesized in pulse microwave assisted polyol process have better catalytic activity for the oxidation of methanol to carbon dioxide than those synthesized in continuous process. 相似文献
225.
Machining of micro holes with micro electro- chemical machining (micro ECM) process has been carried out with an indigenously developed set up. This paper describes relevant problems and solutions for the circular micro holes machining process on 304 stainless steel sheets with 60 μm thickness using high speed steel cylindrical tool of diameter 500 ~tm and using dilute I-I2SO4 as elec- trolyte. The taper angle variation of the machined hole is analyzed and reported for different experimental setting parameters. The minimum value of the taper angle of machined holes is achieved at the parameter setting of 0.4 mol/L H2504, 700 kHz, 600 ns and 21 V, for stainless steel sheets and HSS tool. 相似文献
226.
在壳聚糖-氮掺杂石墨烯-十二烷基苯磺酸钠复合膜电极上实现了多巴胺(DA)和对乙酰氨基酚(PT)的同时测定.用循环伏安法(CV)和差分脉冲法(DPV)研究了DA和PT在该修饰电极的电化学行为.结果表明,在pH=5.0的磷酸缓冲溶液(PBS)中,修饰电极对于DA和PT的电化学氧化具有良好的催化性能.DA的氧化峰电流在2~10、10~90μmol/L浓度范围内呈良好的分段线性关系,检出限为0.178 μmol/L,PT的氧化峰电流在4~150μmol/L浓度范围内呈良好的线性关系,检出限为1.06μmol/L.实验结果表明,十二烷基苯磺酸钠能显著提高检测的灵敏度,选择性和重现性. 相似文献
227.
228.
A. W. S. Watson 《Journal of sports sciences》2013,31(2):131-140
The subjects were 31 successful schoolboy rugby players and 25 successful schoolboy hurlers; 34 non‐team members acted as controls. Thirty‐one anthropometric measurements were taken on each subject: height, weight, sitting height, five skeletal lengths, six skeletal diameters, 13 muscle circumferences and four skinfolds. The non‐players were significantly smaller than both the rugby players and the hurlers in weight, biacromial diameter, bideltoid, neck, chest, flexed arm, upper and lower thigh and calf circumferences. The non‐players were significantly smaller than the rugby players in arm length, femur diameter and waist, hip and relaxed arm circumferences. The non‐players were significantly smaller than the hurlers in femur length, biiliac and ankle diameters. There were no statistically significant differences between the rugby players and hurlers. Discriminant analysis produced a function containing terms for height, weight, fat free weight, humerus diameter and neck, bideltoid, forearm and calf circumferences which correctly assigned 83 (92%) of the subjects to ‘player’ and ‘non‐player’ categories. When the function was applied to the 15 members of the rugby team of a different school, 14 were placed in the ‘player’ category and one subject was given a borderline classification. It is concluded that there were differences in physique between the team members and non‐members and that the techniques used in the study were effective in quantifying them. 相似文献
229.
《European Journal of Sport Science》2013,13(3):312-320
Abstract In 1972, the term ‘kinanthropometry’, derived from the Greek words ‘kinein’ (to move), ‘anthropos’ (human) and ‘metrein’ (to measure), was launched in the international, Francophone journal Kinanthropologie by the Canadian William Ross and the Belgians, Marcel Hebbelinck, Bart Van Gheluwe and Marie-Louise Lemmens. The authors defined this neologism as ‘the scientific discipline for the study of the size, shape, proportion, scope and composition of the human being and its gross motor functions’. Presenting a theoretical framework for the analysis of the internal social processes of discipline formation – derived from the social history-of-science tradition – this article critically examines whether kinanthropometry was indeed promoted and developed by its community members as a scientific discipline. Therefore, the focus will be on its conceptualisation and positioning within the field of kinanthropology/kinesiology and on its development by a scholarly association, i.e. the International Working Group on Kinanthropometry (IWGK). The strong emphasis of the kinanthropometry community on the standardisation of measurement techniques and its practical and professional application hampered its disciplinary development. Findings of this study could serve as a basis for future ‘fundamental’ investigations addressing questions of disciplinary development within the field(s) of physical education, kinesiology and sport science(s). 相似文献
230.
微型企业为我国经济发展作出了突出贡献,但融资难却成为制约微型企业发展的最大障碍.本文总结了我国微型企业信贷融资概况以及存在的问题,在此基础上,分别从政府与监管部门、银行和微型企业自身角度提出了解决我国微型企业融资问题的主要途径,最后对"微贷款"这一信贷模式进行分析,得出"微贷款"是解决微型企业信贷融资困境的有效实践. 相似文献