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241.
利用牛顿迭代法作为预测步,用不动点迭代法作为修正步,结合filter技术,提出了求解非线性互补问题的两步迭代-filter算法,并证明了算法的局部三阶收敛性,最后通过数值实验表明该算法的有效性. 相似文献
242.
Critical Metaphor Analysis is a new method of critical discourse analysis. It aims at revealing attitudes, believes, emo?tions and ideologies of a specific group by comprehensively adopting the knowled... 相似文献
243.
Torun Granstrøm Ekeland 《Scandinavian Journal of Educational Research》2017,61(3):319-332
The article examines the use of archaeological knowledge in elementary history textbooks used in Norwegian schools today. The aim is to determine whether we can find any traces of colonialism by reviewing how these narratives perform in interrelations within and between the Sámi and Norse pasts, and how the narratives allow for hybridity and heterogeneity. Postcolonial theory turns the narrative into an object of analysis. The findings show that the Sámi material remains are outside the system of cultural change and that the temporal and spatial distances produce binary and homogeneous cultures. New material perspectives can intervene in singular performativity. Learning to enact dynamic material heterogeneity may affect the future of pupils’ participation in cultural negotiations of pastsin present. 相似文献
244.
张爱娣 《广播电视大学学报》2011,(4):62-69
晚清民国时期,中国的小报繁盛。小报不论是在发行量上,还是对整个社会的影响力方面都起到了当时大报不可取代的作用,而当下小报不仅种类繁多,而且在发行、销量、社会影响方面也越发呈现出不俗的表现。在这两个阶段中,小报为什么能够在强势大报中争得自己的一席空间,原因在于小报在整个报业产业中,以其独特的发声方式,有别于主流大报的话语... 相似文献
245.
Brady D. Lund 《Public Services Quarterly》2020,16(2):112-123
AbstractThis article discusses the use of R programing language for executing a sentiment analysis of tweets pertaining to library topics. This discussion is situated within the literature of marketing and management sciences, which is employing methods of machine learning and business intelligence to make informed decision-making, and library administration, which has expressed great interest in social media engagement within its literature but has yet to adopt these types of analysis. Presented in this article is a sample code with instructions on how users may execute it within R to retrieve and analyze tweets relevant to library services. Two examples created using the code (analysis of top librarians’ tweets and analysis of posts about major book publishers) are used to demonstrate the functionality of the code. The code presented in this article may be used by libraries to analyze tweets about their library and library-related topics, which, in turn, may inform management and marketing design. 相似文献
246.
[目的/意义]针对当前知识发现服务中存在的个性化程度不高和推荐效果不佳等问题,提出一种基于用户兴趣度量和内容分析的推荐算法。[方法/过程]文章通过特征词分布、LDA主题分布、引文结构网络三个维度构建学术资源模型,并通过对用户行为的度量,计算用户对其浏览学术资源的兴趣度,结合学术资源模型构建用户兴趣模型。将用户兴趣模型与学术资源模型匹配,计算其相似度,得到用户对每条学术资源的兴趣值,最后将兴趣值最高的TOP-N学术资源推荐给用户。[结果/结论]通过实验检验算法的有效性和推荐准确率,结果显示,本文从实时动态度量兴趣的角度,提出的推荐算法能较好地预测用户兴趣,推荐效果显著,为实现发现服务精准推荐提供思路。 相似文献
247.
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
248.
BackgroundAlthough adverse childhood experiences (ACEs) are relatively common among children, there is limited knowledge on the co-occurrence of such experiences.ObjectiveThe current study therefore investigates co-occurrence of childhood adversity in the Netherlands and whether specific clusters are more common among certain types of families.Participants and SettingRepresentative data from the Family Survey Dutch population 2018 (N = 3,128) are employed.MethodWe estimate Latent Class Analysis (LCA) models to investigate co-occurrence of ACEs. As ACEs we examine maltreatment, household dysfunction, demographic family events, as well as financial and chronic health problems. Gradual measures for maltreatment and financial problems are studied to make it possible to differentiate with regard to the severity of experiences.ResultsOur results show that four ACE clusters may be identified: ‘Low ACE’, ‘Moderate ACE: Household dysfunction’, ‘Moderate ACE: Maltreatment’ and ‘High ACE’. Regression analyses indicated that mother’s age at first childbirth and the number of siblings were related to experiencing childhood adversity. We found limited evidence for ACEs to be related to a family’s socioeconomic position.ConclusionThe found clusters of ACEs reflect severity of childhood adversity, but also the types of adversity a child experienced. For screening and prevention of childhood adversity as well as research on its consequences, it is relevant to acknowledge this co-occurrence of types and severity of adversity. 相似文献
249.
As methods for automated scoring of constructed‐response items become more widely adopted in state assessments, and are used in more consequential operational configurations, it is critical that their susceptibility to gaming behavior be investigated and managed. This article provides a review of research relevant to how construct‐irrelevant response behavior may affect automated constructed‐response scoring, and aims to address a gap in that literature: the need to assess the degree of risk before operational launch. A general framework is proposed for evaluating susceptibility to gaming, and an initial empirical demonstration is presented using the open‐source short‐answer scoring engines from the Automated Student Assessment Prize (ASAP) Challenge. 相似文献
250.
为更好地了解国外体育创新创业领域研究的前沿热点和发展趋势,明晰我国发展的不足。运用文献计量法、数理统计法等对1968—2018年Web Of Science(SSCI、SCI等核心库)中的收录的123篇文献进行了计量分析。结果表明:国外体育创新创业领域已取得一定的成果,但也仍存在作者合作脉络单一、实证研究单薄、案例分析不够全面等问题,建议国内应取长补短,从巩固理论研究、深入实证研究、加强协作脉络、延伸企业家精神内涵等方面入手,以期更好地促进我国体育创新创业领域的发展。 相似文献