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71.
72.
针对三段式分类索刊号的编号方法及在实际应用中存在的不足提出商讨意见,并对刊次号的设计提出看法。 相似文献
73.
Question classification systems play an important role in question answering systems and can be used in a wide range of other domains. The goal of question classification is to accurately assign labels to questions based on expected answer type. Most approaches in the past have relied on matching questions against hand-crafted rules. However, rules require laborious effort to create and often suffer from being too specific. Statistical question classification methods overcome these issues by employing machine learning techniques. We empirically show that a statistical approach is robust and achieves good performance on three diverse data sets with little or no hand tuning. Furthermore, we examine the role different syntactic and semantic features have on performance. We find that semantic features tend to increase performance more than purely syntactic features. Finally, we analyze common causes of misclassification error and provide insight into ways they may be overcome. 相似文献
74.
从利益相关者的视角来看,综合素质评价结果一旦与学生、教师和高中学校的利益高度相关,那么由这些利益高度相关的主体来进行评价时,由于受到"理性经济人"自利性的制约,利益高相关主体极有可能因自身利益的最大化并最终导致评价结果的失真。评价结果的客观性取决于"评价什么",更取决于"谁来评价",甚至可以说,"谁来评价"会直接影响着"评价什么"。而就综合素质评价的实施来看,学生更多的是综合素质评价材料的记录主体,高中学校(包括行政管理人员和教师等)更多的是综合素质评价材料真实性的监督主体,而高校才是最终、最佳的综合素质评价主体。 相似文献
75.
积极阅读价值观对于形成健康科学的阅读行为和保持文化自觉、文化自信有着重要意义。文章通过分析积极阅读价值观的相关理论和阅读价值观存在的问题,探讨制约积极阅读价值观形成的因素,提出培养积极阅读价值观的路径,以期对积极阅读价值观的建构机制进行深入研究。 相似文献
76.
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
77.
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
78.
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
79.
竺润祥 《宁波大学学报(教育科学版)》2007,29(6):81-83
文章首先分析目前我校学位论文选题中存在的问题,针对影响选题质量的有关因素提出建议以改进选题工作,提高学位论文质量。 相似文献
80.
张怡 《渭南师范学院学报》2011,26(2):89-91,94
文献信息建设是高校教育特别是新增专业建设和发展的重要内容,也是其三大支撑性要素之一,而我国各个院校都面临着新增专业学科文献信息建设明显不足和失措的困境.这种普遍性状况源于新增专业学科文献信息建设中先天性、源头性、境遇性、制度性和主体性等一系列相互关联的因素.各院校图书馆应该坚持对策性原则,加强新增专业文献信息建设,以走出目前的困境并推进新增专业的学科发展. 相似文献