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951.
952.
“大数据”是当今社会继矿产资源、人力资源之后的一个新兴重要资源。秦皇岛是全国第一个将数据产业化的城市,并在开发区建立了“数谷”数据产业基地。在不断发展的同时,诸如电费过高、光纤不足、周边环境和公共交通有待完善等问题也随之暴露。文中通过在基地内发放调查问卷搜集数据,运用 SPSS19.0进行数据分析,再用AMOS17.0软件构建秦皇岛数据产业升级的结构模型,并对潜变量之间的路径关系进行结果分析。研究表明,对产业升级影响最大的因素是公共政策,其次是创新能力、市场需求、产业聚集和人力资源,最后结合路径图及结论,提出相应的建议。  相似文献   
953.
为降低铁路单线隧道接触网弓形腕臂预配施工难度,论文研究了一种接触网弓形腕臂预配平台,结合单线隧道内弓形腕臂数据精测技术及计算软件,精确测量预配,保证弓形腕臂的安装精度和质量,使弓形腕臂在现场施工中一次成优。论文结合实际,就某铁路单线隧道接触网弓形腕臂预配平台作具体分析。  相似文献   
954.
955.
There is a steady global trend towards “Data Localization,” laws by which data is required to be maintained and processed within the geographic boundaries of its state of origin. This development has raised concerns about its possible adverse impacts on emerging data-intensive technologies such as Cloud services/E-commerce, Big Data, Artificial Intelligence and the Internet of Things (collectively, the Embedded Infosphere). The inability to reach an international agreement on rules for cross-border data flows may have significant adverse consequences for all future users of the Internet.The basis of Data Localization is grounded in two distinct but inter-related policy models: Data Sovereignty and Trans-Border Data Flows. These two concepts have different origins. “Data Sovereignty” is derived from the historic power of a state of absolute and exclusive control within its geographic borders. Policies behind TBDFs arose in Europe following World War II, primarily motivated by Nazi use of early proto-computers to help round up Jews and others. As they have evolved, TBDF policies have been directed primarily at protecting personal data and privacy.This article first examines the issues of: 1) “Information Sovereignty” and 2) TBDFs. It then describes the arguments for and against “Data Localization,” offers some examples of strong localization policies (Russia, China), and summarizes contesting policy proposals. It then contextualizes TBDF with issues of human rights (free flow of information) and privacy.While the utility of an international agreement on TBDFs is clear, the differences in approaches are tenacious. For the free-market developed world (e.g, EU, OECD), the path forward seems to lead through policy convergence to compatible rules, with differentiated levels of data protection and accountability. It is far from clear whether these rules will address, in a mandatory way, issues of the “free flow” of information in the human rights sense. At the same time, there are countries (e.g., BRICS), representing a majority of the world's population, in which political and cultural resistance will produce stringent Cyber Sovereignty and Data Localization policies with few if any human rights components.The article concludes that the more the Internet is “localized”, the more attenuated its benefits will become. The negative consequences of Data Localization will become increasingly obvious as new, data-intensive technologies become ubiquitous, creating a condition of “Data Dependence”. It is projected that in the future the nations with the least amount of Data Localization and the most open flow of information will be the most successful in benefiting from new data-intensive embedded, networked technologies. This will most likely be characterized by values adopted as policies and practices in the EU.  相似文献   
956.
957.
Using high-frequency data for major volatility indexes, we compute the volatility of volatility and show that its logarithm follows a fractional Brownian motion with Hurst parameter smaller than 1/2 thereby extending to the volatility asset class the recent findings obtained for the equity index markets. The results confirm that the volatility of volatility is a rough process and it possesses the long memory property. We also show that the correlation between the volatility and the volatility of volatility is positive, consistent with observations in the volatility option market. Lastly, a robustness check using volatility futures confirms the findings.  相似文献   
958.
This study revisits the impact of distance on international tourist behaviours in Hong Kong. This work divides and cross-validates the concept of distance into physical and cultural distance. This work also proposes an alternative cultural distance measure by introducing optimal weight amongst Hofstede's dimensions and then compares the proposed measure with the traditional Kogut and Singh's and Kandogan's measures. By using data from the Visitor Profile Report of the Hong Kong Tourism Board and the World Trade Organisation from 2002 to 2017, along with latent growth curve modelling, multivariate regression and panel data analysis, findings confirmed the significant role of physical and cultural distance. In addition, quadratic relationships are detected using cross-validation methods. The effect of physical distance on tourist demands clearly dominates that of cultural distance in the overall market. The problem of spurious correlation and the results of three cultural distance measures are also discussed.  相似文献   
959.
960.
In this paper, we study the relationship between different proxies of firm‐level markups and trade status, using balance sheet information linked to detailed trade data from Hungary between 1995 and 2003. We find that importing is strongly positively correlated with markup measures, both across and within firms. We argue that this correlation can reflect three channels: self‐selection, higher physical productivity resulting from access to a larger variety of inputs, and quality upgrading based on high‐quality imported intermediate inputs. We present evidence for the relevance of the third channel by showing that importers’ markup premium is higher when inputs arrive from developed countries, and that importing is correlated with higher‐quality (price‐adjusted revenue) exports. We find no robust evidence for exporter premium when controlling for importing. We argue that the non‐existent exporter premium might result from the stronger competition in export markets relative to domestic markets.  相似文献   
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