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1.
随着信息技术的发展,数字经济已经成为经济增长的"新引擎"。但由于缺乏权威的产业统计分类标准,学者们一直面临"数字经济研究缺乏数字依据"的尴尬境地。文章基于国家统计局公布并实施的《数字经济及其核心产业统计分类(2021)》中的分类标准,对各省份统计年鉴的数据进行重新整理,利用熵权法构建数字经济发展指数,测度了我国30个省份的数字经济发展水平,分析了各省份数字经济发展的差异以及时空特征。研究发现,2009—2019年我国数字经济产业发展迅猛,各项子产业都取得了长足的进步。相比较而言,数字要素驱动业发展速度略低于其他三个子产业;数字经济发展存在着明显的区域不平衡。东中部地区的数字经济发展状况明显优于西部地区,南方优于北方,而且区域不平衡有持续扩大趋势。 相似文献
2.
《Risk analysis》2018,38(9):1988-2009
Harbor seals in Iliamna Lake, Alaska, are a small, isolated population, and one of only two freshwater populations of harbor seals in the world, yet little is known about their abundance or risk for extinction. Bayesian hierarchical models were used to estimate abundance and trend of this population. Observational models were developed from aerial survey and harvest data, and they included effects for time of year and time of day on survey counts. Underlying models of abundance and trend were based on a Leslie matrix model that used prior information on vital rates from the literature. We developed three scenarios for variability in the priors and used them as part of a sensitivity analysis. The models were fitted using Markov chain Monte Carlo methods. The population production rate implied by the vital rate estimates was about 5% per year, very similar to the average annual harvest rate. After a period of growth in the 1980s, the population appears to be relatively stable at around 400 individuals. A population viability analysis assessing the risk of quasi‐extinction, defined as any reduction to 50 animals or below in the next 100 years, ranged from 1% to 3%, depending on the prior scenario. Although this is moderately low risk, it does not include genetic or catastrophic environmental events, which may have occurred to the population in the past, so our results should be applied cautiously. 相似文献
3.
Catherine Johnson Michelle DeMars Norma Durian Trina Boykin Nolen Contributors 《Serials Review》2020,46(2):163-167
AbstractMichelle DeMars reviews The Indispensable Academic Librarian: Teaching and Collaborating for Change; Norma Durian reviews The Library Outreach Casebook; Trina Boykin Nolen reviews Licensing Digital Content: A Practical Guide for Librarians, Third Edition. 相似文献
4.
This research note reflects on the gaps and limitations confronting the development of ethical principles regarding the accessibility of large-scale data for civil society organizations (CSOs). Drawing upon a systematic scoping study on the use of data in the United Kingdom (UK) civil society, it finds that there are twin needs to conceptualize accessibility as more than mere availability of data, as well as examine the use of data among CSOs more generally. In order to deal with the apparent “digital divide” in UK civil society – where, despite extensive government rhetoric about data openness, organizations face not only the barriers of limited time, funds, and expertise to harness data but also the lack of representation within existing data – we present a working model in which ethical concerns accompanying data utilization by civil society may be better accounted. This suggests there is a need for further research into the nexus of civil society and data upon which interdisciplinary discussion about the ethical dimensions of engagement with data, particularly informed by insight from the social sciences, can be predicated. 相似文献
5.
Hadi Emami 《统计学通讯:理论与方法》2020,49(8):1793-1800
AbstractIn this article we develop the minimax estimation approach of general linear models to the semiparametric linear models when the parameters are simultaneously constrained by an ellipsoid and linear restrictions. Combining sample information and prior constraints the minimax estimator is obtained and compared with partially least square estimator by theoretical and simulation methods. 相似文献
6.
This research focuses upon employment in the new economy, exploring labour protection and social protection in the digital age in China. Through an empirical survey conducted in three Chinese cities, social insurance and the labour rights of employees in the digital economic sector, such as gig employment, e-commerce, and various other forms of online employment, have been examined in-depth. This study reveals new regulatory loopholes in the digital labour market, which have substantially eroded the basis of social policy arrangements in China, “softening” participation in social insurance branches and compliance with labour regulations remarkably. Drawing upon the theoretical concepts of Polanyi on embeddedness and disembeddedness, we argue that the digital employment sector in China has been increasingly disembedded from social institutions and social control. The new configuration in the digital field of social policy requires novel conceptual models and institutional settings to cope with increasing social risks in virtual spaces. 相似文献
7.
罗勇 《重庆大学学报(社会科学版)》2020,26(2):153-162
数字货币,是一种具有财产性价值属性的电磁记录型数据。数字货币在其依存的区块链体系中所彰显的与不特定者之间的支付对价性、与法定货币之间的互换性、使用电子信息处理系统进行转移的在线转移性等特点,得以从数据说的角度,将其作为一种数据性财产权在现行法律框架内对其私法性质进行讨论。有鉴于我国民法总则已将数据纳入保护客体的范畴,数字货币作为数据之一种,理应成为一种新型法律客体,在得到法律理论支撑的基础上获得保护。 相似文献
8.
用联想神经网络设计的信道均衡器 总被引:1,自引:0,他引:1
研究了联想神经网络在数字通信信道均衡器实现中的应用,讨论了其设计方法和设计步骤,给出了计算机模拟结果,并进行了性能比较。研究结果表明:Hopfield联想神经网络实现的信道均衡器具有比传统线性横向均衡器更优越的性能。 相似文献
9.
袁晖坪 《上海理工大学学报(社会科学版)》2002,24(3):214-217,221
给出了复亚半正定矩阵的概念,研究了它的基本性质及行列式理论,将Hermite阵的Schur定理,华罗庚定理,Minkowski不等式,凸性不等式,Ostrowski-Taussky不等式推广到了较广泛的复矩阵类,扩大了Minkowski不等式的指数范围,削弱了华罗庚不等式的条件。 相似文献
10.
数字时代的挑战与教育情报的对策 总被引:1,自引:0,他引:1
王成云 《长春工程学院学报(社会科学版)》2002,3(3):51-52
分析了数字时代的信息特点以及给教育情报领域带来的挑战 ,提出了教育情报面对现实应采取的对策。旨在从某个侧面强化教育信息资源建设的整合度。 相似文献