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131.
This study examines the impact that collective bargaining has on multiple dimensions of teacher compensation, including average and starting salaries, early and late returns to experience, returns to graduate degrees, and the incidence of different pay for performance schemes. Using data from the School and Staffing Survey (SASS) and a more recent data set, the Teacher Rules, Roles and Rights (TR3), we find that collective bargaining has a significant impact on all aspects of current, qualification-specific salary schedules. Further, we find some evidence that bargaining impacts the design of performance pay plans. Specifically, unions tend to encourage teacher bonuses that are based on additional qualifications or duties, but discourage bonuses that directly reward improved student test scores. 相似文献
132.
Larry L. Howard 《Economics of Education Review》2011,30(1):157-176
This paper estimates models of the transitional effects of food insecurity experiences on children's non-cognitive performance in school classrooms using a panel of 4710 elementary students enrolled in 1st, 3rd, and 5th grade (1999-2003). In addition to an extensive set of child and household-level characteristics, we use information on U.S. counties to control for potential confounding effects of the local economic and noneconomic environment on children's household transitions between states of food insecurity and food security. The time horizon of our analysis affords insight into factors underlying children's formation of non-cognitive skills and the efficiency of classroom-based educational production in elementary school. Overall, we find significant negative developmental effects for children with food insecurity at home; and that children experiencing an early transition from food insecurity in 1st grade to food security in 3rd grade have even larger impairments that persist through 5th grade. 相似文献
133.
Arnaud Chevalier 《Economics of Education Review》2011,30(6):1187-1201
Using a survey of a cohort of UK graduates, linked to administrative data on higher education participation, this paper investigates the labour market attainment of recent graduates by subject of study. We document a large heterogeneity in the mean wages of graduates from different subjects and a considerably larger one within subject with individuals with the most favourable unobserved characteristics obtaining wages almost twice as large as those with the worst. Moreover, gender differences in wages within subjects are also large. We then simulate a graduate tax to calculate a willingness to pay – in form of tuition fees – to capture these subject wage premia. 相似文献
134.
外源性生长激素对运动大鼠骨骼肌形态和代谢机能的影响 总被引:1,自引:0,他引:1
目的:旨在观察生长激素对运动大鼠骨骼肌形态及机能的影响。方法:28只雄性成熟SD大鼠在适应性训练后随机分成安静对照组、安静注射组、运动对照组和运动注射组。运动组和运动注射组进行跑台训练8周。皮下注射rhGH。结果:1)注射生长激素后,出现了肌纤维排列松散,细胞核数量减少且体积变小,骨骼肌细胞间质水肿等现象。2)在8周的训练后,肌纤维横截面积稍有下降,但变化不明显。注射生长激素4周后,安静组和运动组均显著增加,且安静注射组大鼠的肌纤维横截面积显著高于运动注射组。3)运动组及运动注射组骨骼肌IGF-I明显升高。安静注射组及运动注射组血清IGF-I明显升高,运动组无明显变化。4)各组肌肉总蛋白含量有所增加,分别为安静注射组升高4.77%、运动组升高31.13%、运动注射组升高28.06%。5)运动组及运动注射组腓肠肌ATP酶活性升高。结论:1)8周耐力运动明显促进大鼠骨骼肌蛋白质合成,同时增加了骨骼肌IGF-I水平。2)外源性rhGH注射4周后,大鼠骨骼肌细胞形态产生肥大,骨骼肌肌纤维横截面积明显增加。3)外源性rhGH注射4周可以显著提高血清和骨骼肌IGF-I水平,且骨骼肌总蛋白的含量变化与骨骼肌IGF-I的变化趋势平行。4)外源性rhGH注射4周可以对肌纤维类型及分配产生调节作用,从而改变肌肉代谢酶活性。 相似文献
135.
实时虚拟参考咨询服务新尝试——清华大学图书馆智能聊天机器人 总被引:1,自引:0,他引:1
实时虚拟参考咨询服务在图书馆服务中发挥着积极且重要的作用。清华大学图书馆基于开源软件A.L.I.C.E.开发出实时智能聊天机器人"小图",提供参考咨询、图书搜索、自我学习等多种服务,并将其推广至社交网络,取得良好的效果。 相似文献
136.
文章介绍了服务器虚拟化技术和VMware Infrastructure3虚拟架构套件,详细阐述了VMware服务器虚拟化技术在中央民族大学数字图书馆中的应用,结果表明虚拟化后的服务器是稳定和高效的。 相似文献
137.
In this paper, we utilize transmission-line matrix simulations to study the electromagnetic properties of hyperbolic metamaterial grids, which are synthesized by arranging unloaded transmission lines over electrical ground planes, such that the unit cells are rectangular in shape. The hyperbolic grids support Bragg and Hyperbolic resonant modes that have rectangular and hyperbolic dispersion surfaces, respectively. We demonstrate the formation of these resonant modes in the hyperbolic grids and their refraction, and spatial scanning properties via circuit simulations. The simulation results are compared with experimental results of a two-layer anisotropic hyperbolic metamaterial. 相似文献
138.
This article develops a general framework to describe the changes in university IPR regulations in Europe and their effects on the patenting activities of universities and on knowledge transfer processes. Understanding the effects of changes in IPR regulations on academic patenting is a complex issue, and parallels with the US case can be misleading. First, despite the general trend towards institutional ownership, university IPR regulations in Europe remain extremely differentiated and there is no one-to-one mapping to the US system. Second, it is difficult to disentangle the quantitative and qualitative effects of changes in IPR ownership regulations on academic patenting activities from the effects of concurrent transformations in the institutional, cultural and organizational landscape surrounding academic knowledge transfer. The article proposes a review and typological classification of national university IPR ownership systems on the basis of their development since 2000, and uses it to analyze the aggregate dynamics of academic patent ownership in several European countries. The analysis of patterns of ownership of academic patents shows that there has been a general increase in university patenting since 1990, with a significant slowdown (and even reduction in some countries) after early 2000s accompanied by a switch in academic patents ownership in favor of university ownership though preserving the European specificity of high company ownership of academic invented patents. 相似文献
139.
Tércia Zavaglia TorresAuthor VitaeIvo Pierozzi Jr.Author Vitae Nadir Rodrigues PereiraAuthor VitaeAlexandre de CastroAuthor Vitae 《International Journal of Information Management》2011,31(2):121-127
The great contemporary organizational challenge for enterprises is to create a conceptual and methodological framework allows the management of knowledge by means of networks designed for social interaction. This statement is based on the premise that the competitive drive and sustainable success of the company depend on the introduction of new forms of production innovative processes, which can only be ensured through integrated approaches to knowledge management and the incorporation information technologies (IT). This is a reality that has already been accepted by the Brazilian Agricultural Research Corporation (Embrapa, its acronym in Portuguese), a Brazilian research, development, and innovation (RD&I) institution supporting agricultural sector. For some years now, Embrapa has been incorporating what it has learned about knowledge management into its strategic planning process. In this paper, we present a new approach to managing knowledge and information, and we analyze the need for research institutions to administer the knowledge they produce through an RD&I management model based multi- and inter-disciplinary teams, and multi-institutional research networks. 相似文献
140.
我国内陆保税港区集装箱运输的发展策略探讨——以重庆为例 总被引:1,自引:0,他引:1
分析了重庆保税港区发展集装箱运输的优势和面临的独特问题,并提出了相应的对策建议。分析认为,作为我国第一个内陆型双功能保税港区,重庆两路寸滩保税港区具有发展集装箱运输的叠加政策优势、独特资源优势、水运成本优势、雄厚的产业配套以及良好的发展基础,但也面临长江沿线集装箱运输监管困难、综合物流费用抵消集装箱水运成本优势、集装箱运输基础设施能力不足、管理体制制约集装箱保税多式联运的进一步发展等独特问题。关于在内陆保税港区如何开展集装箱运输既没有现成的模式,也缺乏实践的先例,重庆保税港区应当通过创新,在借鉴和学习国内外成功经验的基础上,结合港区特点,充分发挥优势,创造性的解决集装箱运输发展面临的实际问题。 相似文献