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41.
国内外对于语言学习学能和语言学习策略在语言学习过程中的影响的研究有很多,不同程度地探讨了英语学习学能和学习策略对英语语言学习结果的影响,为该研究提供了丰富的理论研究基础。从高校英语教师的角度上探讨大学生的英语学习学能,学习策略对大学英语语言教学的影响。通过相应的语言学习策略教授的研究适时调整大学英语课堂教学活动而产生的学习成效从而得出英语学学能和学习策略在大学英语语言教学活动中的影响,为高校英语课程改革提供相应的研究基础和经验。  相似文献   
42.
针对高职院校微课教学在实践中存在的重比赛、轻应用,重形式、轻实效,重讲授、轻互动,重技术、轻内容等方面的问题,提出通过采取坚持和发挥学生的主体作用,探索基于“互联网+”的混合教学模式,完善对微课教学的激励制度等措施,以进一步规范微课教学,优化其在高职教学中的作用和效果。  相似文献   
43.
针对华北地区尾矿库自动提取问题,将基于深度学习的SSD目标检测模型应用于遥感图像尾矿库提取。首先标记华北地区2 000个样本,随机挑选1 500个作为训练样本,剩余样本作为测试样本,验证模型的检测精度。分析卷积层对应感受野与图像中尾矿库尺寸关系,发现原始SSD模型漏检误检大型尾矿库。改进SSD模型结构,提出增加额外卷积层的策略,提高对大型尾矿库目标的检测精度。实验表明,在置信度阈值为0.3时,改进的SSD模型相比原始模型,检测精确率提高10.0%,召回率提高14.4%,提高了大型尾矿库检测精度。验证了基于深度学习的SSD目标检测模型自动提取尾矿库的可行性以及改进算法的有效性。  相似文献   
44.
为充分发掘分布在不同位置上的雾节点的计算资源,任务卸载被寄予众望。在雾计算场景下,以尽可能减少任务卸载的长期成本为目标,试图寻找一个高效的在线任务卸载方法。为此,这一问题被建模成一个随机规划问题,该问题中系统参数所对应的随机变量的期望会在未知时刻突变,系统参数相关信息只能在任务完成后的反馈中获得。基于非稳态多臂老虎机模型,提出一个高效的算法来解决这一具有挑战性的随机优化问题,给出理论分析证明该算法的渐进最优性。数值实验证明了该算法的优越性。  相似文献   
45.
Although video clubs have been used to support (student) teachers' learning through reflection upon practice, less attention has been paid to their potential use for supporting changes in participants' practice over a period of time. Prior work has also largely treated (student) teachers as an undifferentiated whole that benefits in similar ways from video clubs. In this study, we problematize this assumption by drawing on three cases of student teachers to exemplify three different learning paths while participating in a video club during field placement. Reflecting on these findings, we discuss implications for differentiating the video-club approach to address different student teachers.  相似文献   
46.
Review helpfulness is attracting increasing attention of practitioners and academics. It helps in reducing risks and uncertainty faced by users in online shopping. This study examines uninvestigated variables by looking at not only the review characteristics but also important indicators of reviewers. Several significant review content and two reviewer variables are proposed and an effective review helpfulness prediction model is built using stochastic gradient boosting learning method. This study derived a mechanism to extract novel review content variables from review text. Six popular machine learning models and three real-life Amazon review data sets are used for analysis. Our results are robust to several product categories and along three Amazon review data sets. The results show that review content variables deliver the best performance as compared to the reviewer and state-of-the-art baseline as a standalone model. This study finds that reviewer helpfulness per day and syllables in review text strongly relates to review helpfulness. Moreover, the number of space, aux verb, drives words in review text and productivity score of a reviewer are also effective predictors of review helpfulness. The findings will help customers to write better reviews, help retailers to manage their websites intelligently and aid customers in their product purchasing decisions.  相似文献   
47.
Modern OCR engines incorporate some form of error correction, typically based on dictionaries. However, there are still residual errors that decrease performance of natural language processing algorithms applied to OCR text. In this paper, we present a statistical learning model for post-processing OCR errors, either in a fully automatic manner or followed by minimal user interaction to further reduce error rate. Our model employs web-scale corpora and integrates a rich set of linguistic features. Through an interdependent learning pipeline, our model produces and continuously refines the error detection and suggestion of candidate corrections. Evaluated on a historical biology book with complex error patterns, our model outperforms various baseline methods in the automatic mode and shows an even greater advantage when involving minimal user interaction. Quantitative analysis of each computational step further suggests that our proposed model is well-suited for handling volatile and complex OCR error patterns, which are beyond the capabilities of error correction incorporated in OCR engines.  相似文献   
48.
Five hundred million tweets are posted daily, making Twitter a major social media platform from which topical information on events can be extracted. These events are represented by three main dimensions: time, location and entity-related information. The focus of this paper is location, which is an essential dimension for geo-spatial applications, either when helping rescue operations during a disaster or when used for contextual recommendations. While the first type of application needs high recall, the second is more precision-oriented. This paper studies the recall/precision trade-off, combining different methods to extract locations. In the context of short posts, applying tools that have been developed for natural language is not sufficient given the nature of tweets which are generally too short to be linguistically correct. Also bearing in mind the high number of posts that need to be handled, we hypothesize that predicting whether a post contains a location or not could make the location extractors more focused and thus more effective. We introduce a model to predict whether a tweet contains a location or not and show that location prediction is a useful pre-processing step for location extraction. We define a number of new tweet features and we conduct an intensive evaluation. Our findings are that (1) combining existing location extraction tools is effective for precision-oriented or recall-oriented results, (2) enriching tweet representation is effective for predicting whether a tweet contains a location or not, (3) words appearing in a geography gazetteer and the occurrence of a preposition just before a proper noun are the two most important features for predicting the occurrence of a location in tweets, and (4) the accuracy of location extraction improves when it is possible to predict that there is a location in a tweet.  相似文献   
49.
高职思想政治课的学习效果直接关系到立德树人这一根本任务的落实。在影响高职思想政治课学习效果的诸多因素中,学生自身需求是关键因素。针对这一关键因素,高职思想政治课教师需要综合运用多种措施满足学生需求,提高思想政治课学习效果,真正落实立德树人的根本任务。  相似文献   
50.
The Covid-19 pandemic has driven the fastest changes to higher education across the globe, necessitated by social distancing measures preventing face-to-face teaching. This has led to an almost immediate switch to distance learning by higher education institutions. Anatomy faces some unique challenges. Intrinsically, anatomy is a three-dimensional subject that requires a sound understanding of the relationships between structures, often achieved by the study of human cadaveric material, models, and virtual resources. This study sought to identify the approaches taken in the United Kingdom and Republic of Ireland to deliver anatomical education through online means. Data were collected from 14 different universities in the United Kingdom and Republic of Ireland and compared adopting a thematic analysis approach. Once themes were generated, they were collectively brought together using a strength, weakness, opportunity, threat (SWOT) analysis. Key themes included the opportunity to develop new online resources and the chance to engage in new academic collaborations. Academics frequently mentioned the challenge that time constrains could place on the quality and effectiveness of these resources; especially as in many cases the aim of these resources was to compensate for a lack of exposure to cadaveric exposure. Comparisons of the actions taken by multiple higher education institutions reveal the ways that academics have tried to balance this demand. Discussions will facilitate decisions being made by higher education institutions regarding adapting the curriculum and assessment methods in anatomy.  相似文献   
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