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31.
文章通过对参加十运会女子长拳决赛的12名运动员在预赛、决赛中的技能表现分析发现:在预、决赛中,动作质量、演练水平及难度等各部分技术得分对最后得分影响的偏重程度存在较大区别,动作质量和难度技术发挥的稳定性欠佳,难度技术在决赛中依然保持突前制胜的主导地位。  相似文献   
32.
运动损伤是套路运动训练中需要克服的重要一环,一直困扰着武术套路的发展。随着竞技武术套路竞赛的不断发展,竞争愈来愈激烈,训练水平不断提高,运动损伤也逐渐引起了重视。文章运用访谈法,对十运会女子套路运动员的损伤状况进行了调查分析,分析了损伤产生的原因,并提出了相应的预防损伤的建议。  相似文献   
33.
本文以典型220千伏变电站为研究对象,对220千伏变电站10千伏侧带负荷运行时的继电保护配置方案进行了系统的研究,解决了220千伏变电站10千伏侧带负荷运行保护的选择性和速动性的重大问题,提出采用10千伏简易母线保护克服了传统完全差动保护的缺陷,解决了低压母线故障无速动保护的问题,有效地防止了由于10千伏系统故障波及220千伏电网,引起大面积停电等恶性电网事故,使220千伏变电站10千伏侧带负荷能够安全稳定运行。  相似文献   
34.
Knowledge production and scientific research have become increasingly more collaborative and international, particularly in pharmaceuticals. We analyze this tendency in general and tie formation in international research networks on the country level in particular. Based on a unique dataset of scientific publications related to pharmaceutical research and applying social network analysis, we find that both the number of countries and their connectivity increase in almost all disease group specific networks. The cores of the networks consist of high income OECD countries and remain rather stable over time. Using network regression techniques to analyze the network dynamics our results indicate that accumulative advantages based on connectedness and multi-connectivity are positively related to changes in the countries’ collaboration intensity whereas various indicators on similarity between countries do not allow for unambiguous conclusions.  相似文献   
35.
2001年2月至2002年4月在杭州5个空气质量国控点采集176组PM10样品,分析有机碳(OC)和元素碳(EC)含量,并采用TEOM法同步监测PM10质量浓度,其中在卧龙桥国控点同时测PM2.5质量浓度。全市PM10年日均浓度为119.2mg•m-3。PM2.5年日均浓度为68mg•m-3。PM2.5与PM10质量浓度呈显著的线性关系。PM2.5/ PM10日浓度比值范围在0.31-0.95间变化,平均比值为0.62。OC和EC浓度分别为20.4 mg•m-3和4.0 mg•m-3,其相关性不好表明碳的来源复杂。二次有机碳(SOC)分别占各季OC的 37.1%,45.8%,58.0%,44.7%,表明杭州空气中存在一定的二次有机污染。  相似文献   
36.
第十届全运会男子篮球决赛进攻失误分析   总被引:6,自引:0,他引:6  
通过对十运会男子篮球决赛阶段的46场篮球比赛现场统计,对篮球比赛中的进攻失误的原因、方式等因素分析,针对失误的情况提出可行性的建议,为我国运动员在篮球比赛中减少和避免失误提供参考依据。  相似文献   
37.
基于Multisim10的电机正反转控制电路的设计与仿真   总被引:1,自引:0,他引:1  
Multisim10是电学仿真实验中广泛应用的理想工具。简单介绍了该软件的主要功能和新增功能,并详细介绍了应用Multisim10对电机正反转控制电路的设计与仿真。  相似文献   
38.
数种表面活性剂对鲁米诺-H_2O_2-Fe~(3+),光泽精H:O。AllO和2,9一二甲基一1,IG菲咯琳一H:O。-Cu’”三种化学发光反应的影响情况进行了试验研究,对表面活性剂在化学发光反应中的作用及机理进行了初步讨论.  相似文献   
39.
This paper analyses market valuations of UK companies using a new data set of their R&D and IP activities (1989-2002). In contrast to previous studies, the analysis is conducted at the sectoral-level, where the sectors are based on the technological classification originating from Pavitt [Pavitt, K., 1984. Sectoral patterns of technical change. Research Policy 13, 343-373]. The first main result is that the valuation of R&D varies substantially across these sectors. Another important result is that, on average, firms that receive only UK patents tend to have no significant market premium. In direct contrast, patenting through the European Patent Office does raise market value, as does the registration of trade marks in the UK for most sectors. To explore these variations the paper links competitive conditions with the market valuation of innovation. Using profit persistence as a measure of competitive pressure, we find that the sectors that are the most competitive have the lowest market valuation of R&D. Furthermore, within the most competitive sector (‘science based’ manufacturing), firms with larger market shares (an inverse indicator of competitive pressure) also have higher R&D valuations, as well as some positive return to UK patents. We conclude that this evidence supports Schumpeter by finding higher returns to innovation in less than fully competitive markets and contradicts Arrow [Arrow, K., 1962. Economic welfare and the allocation of resources for invention. In: Nelson, R. (Ed.), The Rate and Direction of Inventive Activity. Princeton University Press, Princeton], who argued that, with the existence of IP rights, competitive market structure provides higher incentives to innovate.  相似文献   
40.
This paper addresses the role that scientific status plays in initial public offerings of technology focused firms. The paper builds on the literature of the sociology of science as well as the work of Spence (1974) and Podolny (1993) and argues that the presence of a Nobel laureate affiliated with a firm making an IPO provides a signal of firm quality to potential investors. Moreover, and building on the work of Podolny and Scott Morton (1999) and Stuart et al. (1999) we hypothesize that the importance of status diminishes as other measures of firm quality become available. We test our hypothesis for two periods of initial public offerings in biotechnology. We document that there is a clear difference in “maturity” of the firms across the two windows on a number of metrics. Consistent with our hypothesis that Nobel laureates play an important role as a non-financial signal of firm quality, we find that first-window firms with a Nobel laureate affiliate realize greater IPO proceeds in the amount of $24 million. In the second window the amount of money raised is not significantly different between Nobel and non-Nobel firms. This finding is consistent with the signaling literature that argues that the importance of a signal is inversely related to the availability of cogent information on firm quality. Consistent with this view, we also find a change between the two windows in the importance of other non-financial metrics used to convey value. Our research is one of the first to examine the dynamic nature of signals. Because we are unable to distinguish the extent to which the reduction in uncertainty at the firm level is correlated with the reduction of uncertainty at the industry level, the question remains as to the extent to which the diminished importance of signals in our second period is due to a change in market uncertainty versus a change in firm uncertainty.  相似文献   
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