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41.
We apply social network analysis methods to describe the evolution of the innovator network of Jena, Germany in the period from 1995 to 2001. We find this evolution to be directed towards an increasing focus on core competencies of the network. Further we analyse the network resulting from R&D cooperations and explain - by means of network regression techniques - that the job mobility of scientists and the technological overlap between the actors, rather than past cooperations, can best predict the resulting structure.  相似文献   
42.
主要针对电力系统运行过程不稳定性和危害进行分析,总结出故障的原因,进行更好的预防。11KV配电线路在我们的电网中是最主要的线路,由于他供电线路长,经过的地形长和比较复杂,所以发生单相接地的故障也较多。由于110KV配电线路采用小电流接地系统,发生单相接地时有时不跳闸,对电网影响较大,我们必须要认真对待。  相似文献   
43.
第十一届全运会各省市田径综合实力分析   总被引:1,自引:1,他引:0  
运用文献资料法、数理统计法、比较分析法和逻辑归纳法,对第11届全运会奖牌和积分进行统计分析,结果表明:从整体上来说,奖牌分布相对分散,各省市综合实力重新洗牌;速度项群中鲁、苏、粤、沪、川实力显著,耐力性项群中鲁、苏、黑优势明显,快速力量项群中翼、鲁前列,综合项目中辽独领风骚;我国田径总体水平不高,但男子110m栏、20km竞走、女子马拉松、铅球、铁饼、链球、20km竞走达到世界水平,有冲击伦敦奥运会奖牌的能力.  相似文献   
44.
This study was designed to assess whether the level of performance of selected Jamaican 11th-grade physics students on some numerical problems on the energy concept was satisfactory and if there were significant differences in their performance linked to their gender, socioeconomic background (SEB), school location, English language and mathematical abilities. The 331 sampled students consisted of 213 boys and 118 girls; 197 students were from a high SEB and 134 students from a low SEB; 296 students were from seven urban schools and 35 students from three rural schools; 112, 153 and 66 of the students had high, average and low English language abilities, respectively, while 144, 81 and 106 of the students had high, average and low mathematical abilities, respectively. An Energy Concept Test (ECT) consisting of six structured numerical questions was employed for data collection. The results indicated that although the students’ level of performance was regarded as fairly satisfactory, there was a lot of room for improvement. There were statistically significant differences in the students’ performance on the ECT linked to SEB, and mathematical abilities in favour of students from a high SEB, and high mathematical abilities, respectively. There was a positive, statistically significant but weak correlation between the students’ (a) mathematical abilities, and (b) English language abilities and their performance on the ECT, while there were no correlations among their gender, school location, and SEB and their performance on the ECT.  相似文献   
45.
以新型荧光试剂2-(11H-苯[a]咔唑)乙基氯甲酸酯(BCEC-Cl)为柱前衍生试剂,采用非水毛细管电泳技术对衍生二肽进行分离.以甲醇和乙腈为溶剂,乙酸-乙酸铵为缓冲体系,采用279nm二极管阵列检测.在甲醇与乙腈体积比为7:3、乙酸铵浓度为50mmol·L^-1、乙酸浓度为0.8mol·L^-1、柱温为25℃、分离电压为28kV的条件下,实现了12种二肽衍生物的基线分离.  相似文献   
46.
The troubled state of affairs in the Federally Administered Tribal Areas (FATA) of Pakistan portends serious repercussions and grave consequences, destined to affect education particularly higher education in the entire tribal belt. Ironically, no extensive study has been conducted, to investigate those dimensions of FATA higher education which have been adversely affected in the aftermath of 9/11. This exploratory study examines those areas which have been badly affected as a result of current turmoil. In fact, the higher education in FATA has its own peculiar dynamics. Inherently, the entire tribal region has very few well-maintained and properly equipped colleges. Lack of adequate educational facilities, multiplied poor security environment has aggravated the entire situation. Law and order situation in the region has undermined the already dilapidated monitoring mechanism of education department. This state of affairs provides breeding ground for extremist propensities and radical tendencies. In reality, very little attention has been devoted to reform the education system in tribal areas. The whole set up needs to be rehabilitated by taking recourse due to the proactive role of international community. The paper concludes with recommendations for policy makers besides offering new avenues for further research.  相似文献   
47.
We examine the announcements of high tech mergers using a relatively new proxy for growth options we call “growth to book.” We find this adds significantly to help explain the premiums paid and announcement period abnormal returns when acquiring tech targets. Higher synergies are expected by managers and investors when targets have low growth options and acquirers have high growth options, resulting in higher premiums paid and either less negative or more positive abnormal returns. However, we find significant variation in the results by the relative size of the target and when low growth to book (GTB) firms acquire. While high GTB acquirers tend to pay more in premiums, low GTB acquirers can pay higher premiums and receive some of the most negative returns at announcement. We find evidence some acquisitions are motivated by desperation as these acquirers have the lowest GTB and do a disproportionate number of the relatively largest deals, receiving the worst abnormal returns at announcement.  相似文献   
48.
介绍了一种用于纺纱车间的温湿度无线监控系统.以STC89C58RD+单片机为核心实现温湿度采集和控制.通过无线传输模块PTR2000实现单片机与上位机、单片机与单片机之间的无线通信.针对现实环境中温湿度控制大时滞、非线性、难以精确建模的特点,单片机采用模糊控制算法实现对温湿度的自动控制.系统具有良好的适应性和稳定性,操作简便,较好解决了纺纱车间对温湿度要求高、人工调节不便的问题.  相似文献   
49.
陈平 《外国教育研究》2007,34(10):66-70
美国学校的公民教育历史悠久,且深入人心。在9.11事件之后,美国学校公民教育的特点主要表现为:深化爱国主义的内涵,寻求国民身份共识;联邦与州政府通过立法、立项,加强对学校公民教育的管理与支持;学校注重围绕公民知识、公民技能、公民气质,进行综合培养与训练。  相似文献   
50.
“9.11事件”之后美国高等教育国际化的四个趋向   总被引:1,自引:0,他引:1  
"9.11事件"的发生,对美国高等教育产生了深远影响。在其后的几年时间中,美国高等教育国际化表现出对赴美留学国际学生签证和学科加以限制、学生赴海外留学目标国家多元化、划拨专款加强外语教学和围绕恐怖袭击开设敏感性区域研讨性课程等趋向。  相似文献   
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