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131.
Data-sharing is an essential tool for replication, validation and extension of empirical results. Using a hand-collected data set describing the data-sharing behaviour of 488 randomly selected empirical researchers, we provide evidence that most researchers in economics and management do not share their data voluntarily. We derive testable hypotheses based on the theoretical literature on information-sharing and relate data-sharing to observable characteristics of researchers. We find empirical support for the hypotheses that voluntary data-sharing significantly increases with (a) academic tenure, (b) the quality of researchers, (c) the share of published articles subject to a mandatory data-disclosure policy of journals, and (d) personal attitudes towards “open science” principles. On the basis of our empirical evidence, we discuss a set of policy recommendations. 相似文献
132.
(International) R&D collaboration and SMEs: The effectiveness of targeted public R&D support schemes
This study analyses the impact and effectiveness of targeted public support for R&D investment at the firm level. We test whether the policy design aiming at incentivizing (international) collaboration and R&D in SMEs achieves input as well as output additionality. Our results show that the targeted public subsidies trigger R&D spending, especially so in internationally collaborating SMEs. We further evaluate the different impact of privately financed and publicly induced R&D investment on innovation performance. The results confirm that the publicly induced R&D is productive as it translates into marketable product innovations. While both types of R&D investments trigger significant output effects, the effect of policy-induced R&D investment on sales from market novelties is highest for international collaborators as well as for SMEs. 相似文献
133.
International knowledge spillovers, especially through multinational companies (MNCs), have recently been a major topic of academic and management debate. However, most studies treat MNC subsidiaries as relatively passive actors. We challenge this assumption by investigating the drivers of knowledge protection intensity of MNC subsidiaries. We argue that knowledge protection intensity is determined by MNC subsidiary mandates and by opportunities and risks originating from the host region. We hypothesize that not just competence-creating but also competence-exploiting mandates increase knowledge protection intensity. In addition, technological cluster regions in the host country can be expected to provide opportunities for knowledge sourcing and MNC subsidiaries may be willing to protect knowledge less intensively to participate in cluster networks. We test our hypotheses using a dataset of 694 observations of 631 MNC subsidiaries in Germany and develop recommendations for research, managers and policy makers. 相似文献
134.
Emad F. Eskander Ahmed A. Abd-Rabou Shaymaa M. M. Yahya Ashraf El Sherbini Mervat S. Mohamed Olfat G. Shaker 《Indian journal of clinical biochemistry : IJCB》2014,29(1):3-7
Viral infection with hepatitis C virus (HCV) has a high propensity in becoming chronic and it is the major cause of hepatocellular carcinoma (HCC) worldwide. This review was basically established to illustrate the putative role of the P53 gene Arg72Pro polymorphism on various cancer models and viral infections, focusing on HCV and HCC incidences. Authors studied the 72 G/C single base substitution of P53 gene at codon 72 using various polymorphic techniques. Intriguingly, authors investigated that the P53 codon 72 plays a crucial role as risk factor in several cancer models. Others found that there is no association between codon 72 genotypes and HCV disease severity or liver cancer. Moreover, the lack of a significant relationship between this polymorphism and risk of HCC shows that it does not predispose towards hepatocarcinogenesis and the frequent loss of the proline allele in HCV-associated carcinogenesis of the liver plays some critical role in hepatocarcinogenesis. Amazingly, there is a significant correlation between male homozygotes for P53 72Pro with HCV type 1b infection. However, there was no significant difference between the P53 polymorphism and HCV genotypes 2a and 2b. It was concluded that the P53 gene polymorphism at codon 72 has been investigated as potential risk factor in several cancer models and HCV infections. 相似文献
135.
RS码是无线通信遥测信道中最常用的编码方式。TMS320C64x系列DSP是TI公司的高性能定点DSP,该DSP内嵌Galois域运算单元,且对RS译码算法的优化提供支持。文章论述了RS译码算法在C64x系列DSP中的实现过程和优化方法,给出了DSP硬件资源相关寄存器的配置和库函数的调用方法,最后对译码器进行了性能分析。 相似文献
136.
以具体工作中方差分析的两个例子,尝试回答方差教学中经常碰到的两个问题,(1)方差分析能解决什么问题;(2)怎样解释方差分析中F统计量的计算。通过教学过程两种讲授方法的比较,得出从样本数据分布的视角进行F统计量计算的教学方法效果更好。 相似文献
137.
"C"标志是定量包装商品生产企业计量保证能力合格的标志,它代表了生产企业对消费者的一种承诺,可以提高企业的形象和消费者对定量包装商品的信任度。文章从建立计量管理体系、计量器具配备、量值溯源、定量包装商品净含量检验等方面论述了进行"C"标志认证工作应重点关注的问题,为定量包装商品生产企业申请认证工作提供指导。 相似文献
138.
用B3LYP理论研究了大气中F与硝酰氯(ClNO2)及顺/反亚硝酸氯(ClONO)分子反应的机理.在6-311++G**的基组水平上,优化得到了反应物、过渡态、中间体和产物的几何构型,通过振动分析对过渡态和中间体构型进行确认.计算结果表明:F与ClONO分子的反应有三种不同的反应机制,而对ClNO2分子的进攻有两种不同的反应方式.其中F与cis-ClONO发生的直接Cl提取反应是主反应通道,产物P1(NO2+ClF)为主要产物. 相似文献
139.
140.
基于B/S模式的综合信息系统集成平台的安全性措施 总被引:1,自引:0,他引:1
管理信息系统发展到综合信息系统集成阶段后,安全问题成为系统集成工作中必须考虑的一个至关重要的问题。基于B/S模式的综合信息系统集成平台的安全性模型及该模型的具体实现方法、路线,在多用户的Web环境下,既能满足用户的需求又能最大限度地保证系统的安全,具有较强的实用性。 相似文献