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72.
The purpose of this study is to find a theoretically grounded, practically applicable and useful granularity level of an algorithmically constructed publication-level classification of research publications (ACPLC). The level addressed is the level of research topics. The methodology we propose uses synthesis papers and their reference articles to construct a baseline classification. A dataset of about 31 million publications, and their mutual citations relations, is used to obtain several ACPLCs of different granularity. Each ACPLC is compared to the baseline classification and the best performing ACPLC is identified. The results of two case studies show that the topics of the cases are closely associated with different classes of the identified ACPLC, and that these classes tend to treat only one topic. Further, the class size variation is moderate, and only a small proportion of the publications belong to very small classes. For these reasons, we conclude that the proposed methodology is suitable to determine the topic granularity level of an ACPLC and that the ACPLC identified by this methodology is useful for bibliometric analyses. 相似文献
73.
Zhigang Hu Wencan Tian Shenmeng Xu Chunbo Zhang Xianwen Wang 《Journal of Informetrics》2018,12(4):1133-1145
InCites Essential Science Indicators is becoming increasingly used to identify top-performing research and evaluate the impact of institutes. Unfortunately, our study shows that ESI indicators, as well as other normalized citation indicators, have the following flaws. First, the publication month and the online-to-print delay affect a paper’s probability of becoming a Highly Cited Paper (HCP). Papers published in the earlier months of the year are more likely to accumulate enough citation counts to rank at the top 1% compared with those published in later months of the year. Papers with longer online-to-print delays have an apparent advantage for being selected as HCPs. Research field normalizations lead to the third pitfall. Different research fields have different citation thresholds for HCPs, making research field classification important for a journal. In addition, the uniform thresholds for both articles and reviews in ESI affect the reliability of HCP selection because, on average, reviews tend to have higher citation rates than articles. ESI’s selection of HCPs provides an intuitive feel for the problems of normalized citation impact indicators, such as those provided in InCites and SciVal. 相似文献
74.
通信信号的调制识别是目前研究的热点问题.本文给出一种新的数字调制信号识别方法.高速数字专用芯片ADSP2101是此方法具体实现的重要器件,这一方法在实际通信中有着广泛的应用. 相似文献
75.
Amal Durou Ibrahim Aref Somaya Al-Maadeed Ahmed Bouridane Elhadj Benkhelifa 《Information processing & management》2019,56(2):354-366
Handwriter identification aims to simplify the task of forensic experts by providing them with semi-automated tools in order to enable them to narrow down the search to determine the final identification of an unknown handwritten sample. An identification algorithm aims to produce a list of predicted writers of the unknown handwritten sample ranked in terms of confidence measure metrics for use by the forensic expert will make the final decision.Most existing handwriter identification systems use either statistical or model-based approaches. To further improve the performances this paper proposes to deploy a combination of both approaches using Oriented Basic Image features and the concept of graphemes codebook. To reduce the resulting high dimensionality of the feature vector a Kernel Principal Component Analysis has been used. To gauge the effectiveness of the proposed method a performance analysis, using IAM dataset for English handwriting and ICFHR 2012 dataset for Arabic handwriting, has been carried out. The results obtained achieved an accuracy of 96% thus demonstrating its superiority when compared against similar techniques. 相似文献
76.
Sandip Sinharay 《Educational Measurement》2016,35(3):38-54
Data mining methods for classification and regression are becoming increasingly popular in various scientific fields. However, these methods have not been explored much in educational measurement. This module first provides a review, which should be accessible to a wide audience in education measurement, of some of these methods. The module then demonstrates using three real‐data examples that these methods may lead to an improvement over traditionally used methods such as linear and logistic regression in educational measurement. 相似文献
77.
Children's responses to the interactivity of storybook apps in family shared reading events involving the iPad 下载免费PDF全文
《Literacy》2017,51(1):44-52
This paper reports on some data on the effects of screen‐based interactivity on children's engagement with storybook apps during family shared book reading that were gathered in a 2‐year, small‐scale ethnographic case study in Spain. Data analysis focuses on the complex interplay between the storybook app's interactive features and the children's responses to them. Our findings show that interactive elements increase the child's autonomy, as they tend to promote the importance of the reader, positioning him or her as a collaborator, storyteller, an author or an internal character in the fiction; something that can materialise in exciting narrative strategies that can trigger powerful responses to digital literary texts in emergent readers, including playing, creating new fictions or engaging emotionally with the story. Finally, we argue that the Reader Response models that have been used over recent decades to understand children's reading experiences with storybooks need to be revised to better understand their current experiences with interactive texts. 相似文献
78.
应收账款管理创新研究 总被引:1,自引:0,他引:1
张尧洪 《宁波职业技术学院学报》2004,8(6):29-31
在传统应收账款管理方法的基础上,企业应运用维.帕累托(Vilfredo.Pareto)最优分析法对应收账款进行分类管理。即把已有客户分为核心客户、主要客户和一般客户,对他们实行不同的信用管理。对新客户运用稳健分析模型进行信用分析,然后做出销售决策。对销售人员确立应收账款管理目标,以应收账款质量提高作为目标管理的主要内容,企业销售人员的考核与应收账款质量的提高挂钩,建立应收账款管理的激励和约束机制。 相似文献
79.
梦是文学创作的一种特殊的表达方式。在小说《简爱》中,夏洛蒂.勃朗特通过梦的意象把女主人公简爱充满疑虑和矛盾的内心展现在读者面前。该文对小说中的梦境描写进行了归类并对其作了进一步分析,展示通过梦意象的运用产生了震撼人心的艺术效果,增强了思想感情表达的艺术张力。 相似文献
80.
两汉藏书各有千秋 ,无论从藏书的数量和质量 ,还是从藏书的途经和手段来说都有各自的特色 ,然而在其对文化传播的影响 ,对图书馆的产生与发展 ,对经学理论的体系化等方面又走到了一起 相似文献