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91.
在存在研发成果溢出与研发投资溢出时,建立了以产量竞争的古诺双寡头两阶段博弈模型。在四种不同的R&D策略下,比较了两种溢出方式下企业的R&D水平。研究表明:当存在研发成果溢出时,与存在研发投资溢出相比,企业有较高的R&D水平;当存在研发投资溢出时,每个企业的R&D水平随着溢出水平的提高而下降;在没有溢出效应时两个模型是等价的。从促进技术进步的角度来看,无论是存在研发成果溢出还是存在研发投资溢出,在四种策略中,研究联合体策略优于其他任何一种策略。 相似文献
92.
分别在油菜的蕾苔期、初花期喷施一定浓度的植物生长调节剂萘乙酸、微量元素锶和硼的混合配方,可以有效地促进植株生长发育;增强油菜光合作用;提高油菜花蜜腺的泌蜜量;同时,主花序有效长度增长;分枝部位降低;千粒重和角果数增加;发病率降低,从而使油菜籽产量增加12%以上;含油率增加4%以上;品质显著改善。微量元素增加;其中锶增加最为明显。 相似文献
93.
Krista Court 《Journal of Further & Higher Education》2014,38(3):327-345
Providing feedback on draft essays is an accepted means of enacting a social-constructivist approach to assessment, aligning with current views on the value of formative feedback and assessment for learning (AFL). However, the use of this process as a means of improving not only content but also students' academic writing skills has not been widely studied, despite a widespread perception that there is scope for intervention at university level. This article explores the developmental potential of a drafting/tutor feedback/redrafting process on a first-year undergraduate course for trainee English language teachers at a UK university. The aims of this small-scale, largely qualitative study were to ascertain students' perceptions of the process and to determine the extent to which the process could contribute to the development of students' academic writing. Data are derived from first and second draft essay marks and questionnaires administered to 32 students. Findings suggest that feedback on drafts is acted on and can contribute to improved work when it is timely and detailed and when it raises students' metacognitive awareness, as was the case in this project. Also noteworthy, however, are the students' perceptions that redrafting is cognitively challenging and time-consuming. Comments from a less academically confident student with regard to the quantity of feedback and its detrimental impact are of particular concern. Questions are raised regarding the use of tutor reformulation, the sustainability of AFL and the provision of feedback to – and its interpretation by – weaker students. Finally, some key indicators for improved future practice are presented. 相似文献
94.
95.
As an effective technique for improving retrieval effectiveness, relevance feedback (RF) has been widely studied in both monolingual and translingual information retrieval (TLIR). The studies of RF in TLIR have been focused on query expansion (QE), in which queries are reformulated before and/or after they are translated. However, RF in TLIR actually not only can help select better query terms, but also can enhance query translation by adjusting translation probabilities and even resolving some out-of-vocabulary terms. In this paper, we propose a novel relevance feedback method called translation enhancement (TE), which uses the extracted translation relationships from relevant documents to revise the translation probabilities of query terms and to identify extra available translation alternatives so that the translated queries are more tuned to the current search. We studied TE using pseudo-relevance feedback (PRF) and interactive relevance feedback (IRF). Our results show that TE can significantly improve TLIR with both types of relevance feedback methods, and that the improvement is comparable to that of query expansion. More importantly, the effects of translation enhancement and query expansion are complementary. Their integration can produce further improvement, and makes TLIR more robust for a variety of queries. 相似文献
96.
基于典型相关分析的区域创新系统投入与产出关系研究 总被引:1,自引:0,他引:1
以区域创新系统创新投入与创新产出关系为研究对象,应用典型相关分析方法进行了实证研究。研究结果表明,区域创新投入与创新产出具有相关性,且相关关系显著;研究与发展全时人员当量对发明专利授权数有显著的促进作用;国家创新基金获得资金对科技型企业新产品销售收入具有显著的促进作用;人均固定资产对高新技术企业数量和企业新产品销售收入具有抑制作用;规模以上工业企业研究开发人员数对高新技术企业数量和企业新产品销售收入具有显著的促进作用。并在此基础上给出了政策建议。 相似文献
97.
98.
考虑到最优反馈控制在部分执行器(传感器)失效时仍能使系统稳定运行的条件,给出了求解该总理的算法,并用实例作了说明。 相似文献
99.
为研究不同污染物处理过程中清洁生产技术的差别,以现有环境技术效率的研究为基础,提出工业清洁生产技术效率概念,并基于非期望产出角度的SBM模型,评价我国除西藏外30个省市的工业清洁生产技术效率。研究表明,在我国废水、废气和固废处理过程中,工业清洁生产技术效率存在着显著差异,其中工业废水处理过程中的清洁生产技术效率整体水平最高且发展趋势最好;由区域和省域分析可知,各地区不同污染物处理过程中,工业清洁生产技术效率差异明显,不仅需要分地区制定污染物处理控制政策,还需要针对不同种类污染物的控制情况采取相应措施。 相似文献
100.
Dr. Edward Shapiro 《Research in higher education》1978,9(1):43-67
To the degree that faculty members take into account the relative financial rewards for teaching and research in deciding on the allocation of available time between these two areas, a modification of the reward structure may be expected to produce changes in the amount of time devoted to each. The purpose of this article is to examine with the help of some basic graphic tools of economics the possible results on the quantity of teaching and the quantity of research that may follow from a modification of the reward structure. The possible results are analyzed in terms of displacement, salary, and work effects of the modification. 相似文献