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81.
介绍了一种太阳能电池片胶带全自动贴付机的具体设计方案,设备在经过一段时间的试生产后达到了预期的设计效果。 相似文献
82.
Marc Baudry 《Economics of Innovation and New Technology》2017,26(3):202-226
Plant Breeders Rights (PBRs) are sui generis IPRs intended to promote plant variety creation. Two characteristics distinguish PBRs from patents: the research and the farmers' exemptions. This article attempts to assess the impact of these exemption rules on the private value of PBRs. For this purpose, a microeconometric model of PBRs renewals is developed and estimated. This model extends previous models of patents renewals by allowing the use of PBRs-specific variables. It is argued that simple tests on the coefficients associated with key PBRs-specific variables can provide insights into the impact of the two exemption rules. Implementation to PBRs in France over the period 1973–2011 for six major crops suggests that neither the farmers' exemption nor the research exemption have a clear-cut effect on the private value of PBRs. We conclude that there is no evidence to argue in favor of a reform of PBRs. 相似文献
83.
Human-mediated seed dispersal is recognised as an important, but under-researched, issue. To assess the potential for tourists to act as unintentional seed dispersal agents, we reviewed published and unpublished data on seed dispersal via clothing, vehicles (cars) and in/on horses and donkeys, all of which can be used by tourists. Seeds from 754 species of terrestrial plants have been collected from these vectors, 15% of which are internationally recognised environmental weeds. Seeds were collected from personal clothing and equipment (228 species), the fur of donkeys and horses (42 species), horse dung (216 species) and vehicles (505 species). Most were herbs (429 species) or graminoids (237 species) and native to Europe. Annual Poa, White Clover, Kentucky Bluegrass and Yorkshire Fog were the most frequent species. There have been eight studies specifically on tourists, which identified 12 species on clothing, 26 on vehicles and 133 from horse dung. Methods that minimise the risk of tourists as human-mediated dispersal agents may therefore be appropriate for some tourism activities/destinations: suggestions are made. Further sampling using standardised experimental techniques is required to assess the relative risk associated with specific tourist activities and locations and determine which, and how much, seed is transported. 相似文献
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87.
基于New-Cost-DEA模型的污水处理企业成本效率研究 总被引:1,自引:0,他引:1
近年来,中国污水处理企业的数量迅速增加,污水处理能力不断提高,但仍存在运行效率低下的问题。本文运用New-Cost-DEA模型,构建污水处理企业运行成本效率模型,测算13座污水处理企业的运行成本效率,并对运行成本进行分解,寻找造成运行成本损失的原因。结果显示:影响污水处理企业成本效率的因素不仅和投入要素数量有关,而且与投入要素价格有关;污水处理企业的成本效率低,是由于价格因素和配置效率引起的,需要通过降低投入要素的价格和对投入要素进行优化组合来降低运行成本,提高运行效率。 相似文献
88.
在野外实地调查、标本采集、标本鉴定和文献资料整理的基础上,对云南石林县的蕨类植物资源进行研究。目前,共知有蕨类植物30科,57属,112种(包括变种和变型),其中有国家珍稀濒危保护蕨类植物2种。按照用途将这些植物划分为药用、观赏、食用、指示、化工原料、饲料和绿肥6种类型,分析了保护利用蕨类植物资源的必要性,并对如何保护和开发利用云南石林县的蕨类植物资源提出了建议。 相似文献
89.
思维方式、民情风俗、心理以及文学积淀的差异,赋予英、汉语中植物词汇以不同的文化内涵。因此,在英汉翻译中了解与掌握植物词汇的文化意义差异是达到"真实"翻译所必备的条件。本文通过对英语汉语植物词汇的差异比较,提出了三种具体的翻译方法。 相似文献
90.
Natalia Ramondo 《The Scandinavian journal of economics》2009,111(4):789-809
This paper presents new evidence on foreign plants and their effects on a host industry. I test the predictions of a Melitz‐type model using a panel of domestic and foreign plants in the Chilean manufacturing sector. Foreign ownership is a strong predictor of plant productivity and size advantages. Moreover, productivity gains for a domestic incumbent are positively associated with foreign plants' presence in the same industry and region. I also find a positive correlation between foreign entry and exit of less productive domestic plants, but inconclusive evidence on the effects on productivity of new domestic plants. 相似文献