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101.
The present study analyzes the humor of David Letterman from a balance theory perspective. From this perspective it is predicted that the relationship of the audience to the subject of the joke will influence the amount of audience response to that joke. Significant ANOVA and follow‐up Duncan multiple range test results support the hypothesis and are interpreted in terms of the relational balance theory perspective. 相似文献
102.
根据油罐故障分析,建立了油罐故障诊断模型。采用新型的支持向量机-最小二乘向量机(LS-SVM)的算法对此诊断模型进行预测,获得了满意的效果。该方法易于使用,很少受不确定性因素的影响,有很高的预测准确性。 相似文献
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介绍了空间矢量脉宽调制(SVPWM)的基本原理,提出了在Matlab/Simulink环境下用S函数实现空间矢量脉宽调制模块的方法,描述了仿真模型的设计过程和编程要点,并将其应用到有源电力滤波器的仿真系统中。给出了仿真结果,为基于SVPWM的有源电力滤波器的研究打下了基础。 相似文献
105.
【目的】 为解决审稿专家信息更新不及时、编辑凭经验送审等因素导致拒审的问题,提出一种基于向量空间模型(Vector Space Model,VSM)和余弦相似度的稿件精准送审方法。【方法】 首先,结合文献调研和《数据分析与知识发现》送审情况分析拒审的关键原因;其次,在中国知网中获取该刊审稿专家(155人)近5年发表的全部论文(1805篇),并使用词频-逆文档频度(Term Frequency-Inverse Document Frequency,TF-IDF)方法计算 相似文献
106.
We present a term weighting approach for improving web page classification, based on the assumption that the images of a web page are those elements which mainly attract the attention of the user. This assumption implies that the text contained in the visual block in which an image is located, called image-block, should contain significant information about the page contents. In this paper we propose a new metric, called the Inverse Term Importance Metric, aimed at assigning higher weights to important terms contained into important image-blocks identified by performing a visual layout analysis. We propose different methods to estimate the visual image-blocks importance, to smooth the term weight according to the importance of the blocks in which the term is located. The traditional TFxIDF model is modified accordingly and used in the classification task. The effectiveness of this new metric and the proposed block evaluation methods have been validated using different classification algorithms. 相似文献
107.
This paper presents an investigation about how to automatically formulate effective queries using full or partial relevance information (i.e., the terms that are in relevant documents) in the context of relevance feedback (RF). The effects of adding relevance information in the RF environment are studied via controlled experiments. The conditions of these controlled experiments are formalized into a set of assumptions that form the framework of our study. This framework is called idealized relevance feedback (IRF) framework. In our IRF settings, we confirm the previous findings of relevance feedback studies. In addition, our experiments show that better retrieval effectiveness can be obtained when (i) we normalize the term weights by their ranks, (ii) we select weighted terms in the top K retrieved documents, (iii) we include terms in the initial title queries, and (iv) we use the best query sizes for each topic instead of the average best query size where they produce at most five percentage points improvement in the mean average precision (MAP) value. We have also achieved a new level of retrieval effectiveness which is about 55–60% MAP instead of 40+% in the previous findings. This new level of retrieval effectiveness was found to be similar to a level using a TREC ad hoc test collection that is about double the number of documents in the TREC-3 test collection used in previous works. 相似文献
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数学和物理密切相关,本文以"坡印廷矢量"和"时间延缓"的两个例题为例,通过分析长直螺线管内电磁波能量的传输情况,以及宇宙飞船和地球上的钟时间的显示关系,论述了在物理教学中通过简单的数学推算拓展知识点,不但可以增强教学效果,也可以培养学生严谨的逻辑思维力。 相似文献