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991.
We analyse whether public subsidies supporting collaborative research and development (R&D) projects in small and medium-sized enterprises (SMEs) are able to encourage persistent R&D investment and interorganisational networking more than subsidies supporting individual R&D projects. Adopting a counterfactual approach to policy evaluation, we compare subsidies for collaborative R&D and for individual R&D implemented in the same Italian region in the same period. Our findings suggest that, once public support is no longer available, the two subsidies have different effects on different types of SMEs. If the policymakers’ objective is to increase the number of R&D-performing SMEs over time, they should provide subsidies for collaborative R&D to firms with modest R&D experience. If their objective is to increase the amount of spontaneous R&D investment over time, they should target SMEs with some prior R&D experience, using either subsidy. Finally, if their objective is to induce SMEs to network with external organisations, subsidies for collaborative R&D projects should be preferred to subsidies for individual R&D projects.  相似文献   
992.
This paper contributes to the debate on the energy efficiency paradox according to which consumers fail to adopt cost-effective, energy efficient technologies over less efficient technologies and therefore fail to reduce energy consumption. Both traditional and behavioural theories are used to investigate the decision-making process of residential consumers with empirical evidence based upon a specially designed quasi-experimental survey of 784 households on the decision to connect to a district-heating system, a more energy efficient alternative to individual heating systems. The results suggest an internal discount rate of around 36 per cent for homeowners, a signal that consumers undervalue future energy costs. We also find the household’s decision to be negatively affected by years of payback up to around 7–8 years. Our findings suggest that neglecting consumer inattention and heuristics can lead to biases which cast doubt on the existence of the energy efficiency paradox. We believe that these results help to explain why some consumers are unlikely to invest in energy efficient technology, particularly those on low incomes.  相似文献   
993.
Consecutive proximal-to-distal sequencing of motion is considered to be integral for generating high velocity of distal segments in many sports. Simultaneous usage of proximal and distal segments as seen in martial arts is by far less well investigated. Therefore, the aim of the study was to characterise and differentiate the concepts of consecutive (CSM) and simultaneous (SSM) sequence of motion in straight reverse punches as practised in Practical Wing Chun. Four experienced martial artists succeeded an eligibility test for technical proficiency in both concepts and performed a total number of 20 straight punches per concept. Eight MX13 Vicon cameras (250 fps) and Visual3D were used for motion capture and analyses. Both motion concepts showed proximal-to-distal sequencing of maximal joint velocities but, in SSM, this was coupled with simultaneous initiation. Key characteristics were: high pelvis momentum and backswing of shoulder and elbow (CSM); and importance of shoulder involvement (SSM). Different ranges of motion, timing aspects and achieved maximal angular velocities distinguished both concepts, which led to differences (p < 0.05) in fist velocity at contact, execution time, distance and horizontal shift of the centre of mass. Proper application of both concepts depends on the environmental setting, situational requirements and individual fighting style.  相似文献   
994.
Laceration injuries account for up to 23% of injuries in rugby union. They are frequently caused by studded footwear as a result of a player stamping onto another player during the ruck. Little is known about the kinetics and kinematics of rugby stamping impacts; current test methods assessing laceration injury risk of stud designs therefore lack informed test parameters. In this study, twelve participants stamped on an anthropomorphic test device in a one-on-one simulated ruck setting. Velocity and inclination angle of the foot prior to impact was determined from high-speed video footage. Total stamping force and individual stud force were measured using pressure sensors. Mean foot inbound velocity was 4.3 m ? s?1 (range 2.1–6.3 m ? s?1). Mean peak total force was 1246 N and mean peak stud force was 214 N. The total mean effective mass during stamping was 6.6 kg (range: 1.6–13.5 kg) and stud effective mass was 1.2 kg (range: 0.5–2.9 kg). These results provide representative test parameters for mechanical test devices designed to assess laceration injury risk of studded footwear for rugby union.  相似文献   
995.
以中国生物医药制造业上市公司为样本,采用2012—2015年数据实证分析政府补助的规模与连续性对研发投入和企业绩效的影响,以研究政府研发补助政策的有效性。研究发现,企业研发投入与绩效显著正相关,政府补助可以促进企业加大研发投入,而政府补助的规模对于研发投入与企业绩效存在负向调节作用,政府补贴的连续性对研发投入与企业绩效存在正向调节作用。基于研究结论,提出了调整企业研发补助形式等建议。  相似文献   
996.
以创新驱动发展为研究视角,界定承载研发创新功能的新型研发机构的内涵和形成动因,研究不同信息条件下新型研发机构的作用机理。通过建立数理分析模型发现,在完全信息条件下,通过组织间合作建立新型研发机构,各参与方能够获得经济收益和非经济收益,即使在没有经济收益的极端情况下,参与方也可以获得非经济收益,如学习能力、创新能力、管理能力的提升。在不完全信息条件下,创新研发风险越高,通过各方合作建立新型研发机构,获得的研发创新收益越大。并提出相关建议,以提高新型研发机构的创新能力。  相似文献   
997.
全球研发网络具有路径依赖效应,创新资源在网络内部自由流动产生乘数效应、循环效应、规模效应和输出效应。加快融入全球研发网络,可以从建设海外离岸创新中心着手。借鉴北京中关村、深圳市、上海张江、武汉东湖等海外离岸创新中心建设模式,提出粤港澳大湾区建设海外离岸创新中心的对策建议。  相似文献   
998.
主要基于Web of Science科技论文和Derwent专利文献,利用SATI、SPSS等分析工具,提取文本关键词并构建相异共现矩阵,采用多维聚类方法识别研究热点主题。在继承和发展Naoki Shibata技术机会理论的基础上,通过对比科技论文和专利文献研究热点主题的差异来识别金属3D打印的技术机会。研究得出,科技论文和专利文献分别有4个研究热点主题,识别了两大类共4个技术机会。首次基于专利和科技论文研究金属3D打印的技术机会,开拓了金属3D打印的研究视野,对金属3D打印行业的企业战略决策具有指导作用。  相似文献   
999.
文章介绍了双积分型a/d转换器icl7135的串行数据采集方式在蓄电池电压监测系统中的应用,给出了icl7135与mcs-51单片机串行接口实现电压监测硬件和软件设计方法.  相似文献   
1000.
桌面虚拟实验是当今教育领域研究的热门和前沿技术,它应用于教育领域取得了较好的效果.然而桌面虚拟实验并没有得到相应地推广.适用技术理论为桌面虚拟实验的推广提供了一个思路,本文阐述了综合运用相对比较简单的3DMAX、Flash与Swift3D等适用技术开发桌面虚拟实验的过程.  相似文献   
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