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1.
充分释放大数据技术红利、制度红利和创新红利,对于提高我国体育公共服务供给质量与水平,满足国民日益增长的体育需求,具有重要的理论价值和实践意义。分析了大数据时代我国体育公共服务供给的改革向度,提出了相关改革与发展路径。认为供给主体协同化、供给内容清单化、供给方式智能化、供给监管精准化,是我国体育公共服务供给的改革向度;而主要路径是建构开放共享的信息平台,完善基层体育基础设施,建立完善需求导向机制,建设和完善相关法规制度。  相似文献   
2.
《Journal of Informetrics》2019,13(2):485-499
With the growing number of published scientific papers world-wide, the need to evaluation and quality assessment methods for research papers is increasing. Scientific fields such as scientometrics, informetrics, and bibliometrics establish quantified analysis methods and measurements for evaluating scientific papers. In this area, an important problem is to predict the future influence of a published paper. Particularly, early discrimination between influential papers and insignificant papers may find important applications. In this regard, one of the most important metrics is the number of citations to the paper, since this metric is widely utilized in the evaluation of scientific publications and moreover, it serves as the basis for many other metrics such as h-index. In this paper, we propose a novel method for predicting long-term citations of a paper based on the number of its citations in the first few years after publication. In order to train a citation count prediction model, we employed artificial neural network which is a powerful machine learning tool with recently growing applications in many domains including image and text processing. The empirical experiments show that our proposed method outperforms state-of-the-art methods with respect to the prediction accuracy in both yearly and total prediction of the number of citations.  相似文献   
3.
《Journal of Informetrics》2019,13(3):830-840
This study inserts in the stream of research on the perverse effects that PBRF systems can induce in the subjects evaluated. The authors’ opinion is that more often than not, it is the doubtful scientific basis of the evaluation criteria that leave room for opportunistic behaviors. The work examines the 2004–2010 Italian national research assessment (VQR) to test the lack of possible opportunistic behavior by universities in order to limit the penalization of their performance (and funding) due to the presence of scientifically unproductive professors in faculty. In particular, institutions may have favored “gift authorship” practices. The analysis thus focuses on the output of professors who were unproductive in the VQR publication window, but became productive (“new productives”) in the following five years. A number of universities show a higher than average share of publications by new productives that are in co-authorship exclusively with colleagues from the same university. Although this might be thought to reflect opportunistic behavior by universities, the empirical evidence does not support this assumption.  相似文献   
4.
This paper presents general, closed-form, and exact expressions for cumulative distribution function, probability density function and average value for the ratio of independent η-μ random variables, with arbitrary parameters. More specifically, the outage capacity with peak interference power constraint, the delay-limited capacity, and the ergodic capacity considering constraints on the interference power are derived for non-homogeneous environments containing multipath waves clusters. Numerical curves are presented to evaluate the effects of the general fading variables in spectrum sharing systems. Besides, the results are validated by performing Monte-Carlo simulations. Notably, the provided results find important applications in cognitive radio systems considering the spectrum sharing approach and channels modeled by η-μ distribution.  相似文献   
5.
The modern trends of digitalization have completely transformed and reshaped business practices, whole businesses, and even a number of industries. Blockchain technology is believed to be the latest advancement in industries such as the financial sector, where trust is of prime significance. Blockchain technology is a decentralized and coded security system which provides the capability for new digital services and platforms to be created through this emerging technology. This research presents a systematic review of scholarly articles on blockchain technology in the financial sector. We commenced by considering 227 articles and subsequently filtered this list down to 87 articles. From this, we present a classification framework that has three dimensions: blockchain-enabled financial benefits, challenges, and functionality. This research identifies implications for future research and practice within the blockchain paradigm.  相似文献   
6.
The number of received citations have been used as an indicator of the impact of academic publications. Developing tools to find papers that have the potential to become highly-cited has recently attracted increasing scientific attention. Topics of concern by scholars may change over time in accordance with research trends, resulting in changes in received citations. Author-defined keywords, title and abstract provide valuable information about a research article. This study performs a latent Dirichlet allocation technique to extract topics and keywords from articles; five keyword popularity (KP) features are defined as indicators of emerging trends of articles. Binary classification models are utilized to predict papers that were highly-cited or less highly-cited by a number of supervised learning techniques. We empirically compare KP features of articles with other commonly used journal-related and author-related features proposed in previous studies. The results show that, with KP features, the prediction models are more effective than those with journal and/or author features, especially in the management information system discipline.  相似文献   
7.
This paper analyses the influence of geographic distance on knowledge flows, measured through citations to scientific publications. Previous works using the same approach are limited to single disciplines. In this study, we analyse the Italian scientific production in all disciplines matured in the period 2010–2012. To calculate the geographic distances between citing and cited publications, each one is associated with a “prevalent” territory on the basis of the authors’ affiliations. The results of the application of a gravity model, estimated using ordinary least squares regression, show that despite the spread of IT, geographic distance continues to be an influential factor in the process of knowledge flows between territories. In particular, the analysis reveals that the effect of geographic distance on knowledge flows is significant at the national level, not negligible at the continental level, but completely irrelevant at the intercontinental level.  相似文献   
8.
This paper discusses the problem of the fuzzy sliding mode control for a class of disturbed systems. First, a fuzzy auxiliary controller is constructed based on a feedback signal not only to estimate the unknown control term, but also participates in the sliding mode control due to the fuzzy rule employed. Then, we extend our theory into the cases, where some kind of system information can not be obtained, for better use of our theoretical results in real engineering. Finally, some typical numerical examples are included to demonstrate the effectiveness and advantage of the designed sliding mode controller.  相似文献   
9.
近年来,许多关于社区发现的优秀算法被提出并取得了较好的社区划分效果。但是到目前为止,没有任何一种算法能够同时在时间复杂度和准确度方面取得较好的表现。现实网络中往往存在一些有利于指导社区发现的标签信息,如must-link信息、cannot-link信息等。因此提出基于少量标签信息传播、拓扑结构的半监督社区发现算法S_LPA,分别在karate网络、dolphins网络、LFR基准网络上进行测试。实验结果表明,该算法S_LPA时间复杂度为O(m),相对其它算法,S_LPA在karate网络和dolphins网络的NMI值高于CNM、InfoMap、LPA算法,在LRF网络上准确度高出约20%;提高参数u后,S_LPA算法可识别其它算法不能识别的社区结构。  相似文献   
10.
土地征收对承包权的影响与补偿研究   总被引:3,自引:1,他引:2  
刘灵辉  陈银蓉  成楠 《资源科学》2011,33(2):315-321
承包权是农民依法享有的承包集体土地的资格,是农民享有的一项民事权利。土地征收并不必然导致失地农民丧失集体成员身份,因此失地农民仍享有下轮集体发包土地时承包土地的资格。现行征地制度没有明确失地农民下轮参与承包集体土地的资格,也没有规定征地导致失地农民丧失承包权情况下的补偿措施,这不利于失地农民土地权利的维护,也不利于农村社会的和谐与稳定。本文通过建立土地征收面积(L/)与下轮集体成员人均承包地面积(S)之间的关系模型(L/-S关系函数),分析不同征地规模对失地农民承包权的影响。研究结果表明:土地征收对失地农民承包权的影响与征地面积以及集体原耕地数量存在着密切关系,只有征地面积超过一定限度或者集体耕地压力指数本来就大于1时,失地农民丧失下轮承包集体土地的权利,否则,失地农民并不丧失承包土地的资格。根据研究结论,本文建议征地造成失地农民承包权丧失时,应对失地农民的承包权进行补偿,并将承包权与失地农民的年龄、法定承包年限等联系起来,利用年产值倍数法建立起了承包权的补偿模型.  相似文献   
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