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71.
Minh-Tien Nguyen Viet Cuong Tran Xuan Hoai Nguyen Le-Minh Nguyen 《Information processing & management》2019,56(3):495-515
In the context of social media, users usually post relevant information corresponding to the contents of events mentioned in a Web document. This information posses two important values in that (i) it reflects the content of an event and (ii) it shares hidden topics with sentences in the main document. In this paper, we present a novel model to capture the nature of relationships between document sentences and post information (comments or tweets) in sharing hidden topics for summarization of Web documents by utilizing relevant post information. Unlike previous methods which are usually based on hand-crafted features, our approach ranks document sentences and user posts based on their importance to the topics. The sentence-user-post relation is formulated in a share topic matrix, which presents their mutual reinforcement support. Our proposed matrix co-factorization algorithm computes the score of each document sentence and user post and extracts the top ranked document sentences and comments (or tweets) as a summary. We apply the model to the task of summarization on three datasets in two languages, English and Vietnamese, of social context summarization and also on DUC 2004 (a standard corpus of the traditional summarization task). According to the experimental results, our model significantly outperforms the basic matrix factorization and achieves competitive ROUGE-scores with state-of-the-art methods. 相似文献
72.
Fatemeh Lashkari Ebrahim Bagheri Ali A. Ghorbani 《Information processing & management》2019,56(3):733-755
Traditional information retrieval techniques that primarily rely on keyword-based linking of the query and document spaces face challenges such as the vocabulary mismatch problem where relevant documents to a given query might not be retrieved simply due to the use of different terminology for describing the same concepts. As such, semantic search techniques aim to address such limitations of keyword-based retrieval models by incorporating semantic information from standard knowledge bases such as Freebase and DBpedia. The literature has already shown that while the sole consideration of semantic information might not lead to improved retrieval performance over keyword-based search, their consideration enables the retrieval of a set of relevant documents that cannot be retrieved by keyword-based methods. As such, building indices that store and provide access to semantic information during the retrieval process is important. While the process for building and querying keyword-based indices is quite well understood, the incorporation of semantic information within search indices is still an open challenge. Existing work have proposed to build one unified index encompassing both textual and semantic information or to build separate yet integrated indices for each information type but they face limitations such as increased query process time. In this paper, we propose to use neural embeddings-based representations of term, semantic entity, semantic type and documents within the same embedding space to facilitate the development of a unified search index that would consist of these four information types. We perform experiments on standard and widely used document collections including Clueweb09-B and Robust04 to evaluate our proposed indexing strategy from both effectiveness and efficiency perspectives. Based on our experiments, we find that when neural embeddings are used to build inverted indices; hence relaxing the requirement to explicitly observe the posting list key in the indexed document: (a) retrieval efficiency will increase compared to a standard inverted index, hence reduces the index size and query processing time, and (b) while retrieval efficiency, which is the main objective of an efficient indexing mechanism improves using our proposed method, retrieval effectiveness also retains competitive performance compared to the baseline in terms of retrieving a reasonable number of relevant documents from the indexed corpus. 相似文献
73.
BackgroundChildren exposed to substance use in their families are vulnerable to multiple risk factors in their development and at increased risk for emotional and behavioral problems. The aims of the study were as follows 1) estimate the prevalence of emotional and behavioral problems among children aged 6–11 years old, living with addicted family members in a low-income urban community of São Paulo, Southeastern Brazil; 2) evaluate the children’s exposure to family psychosocial stressors and substance use; and 3) investigate the factors related to the increased risk of emotional and behavioral problems and substance use.MethodsA cross-sectional study was conducted among 101 children aged 6–11 years old (M = 9.16 years, SD = 1.61). The instruments used were a sociodemographic questionnaire, the Child Behavior Checklist (CBCL) and the Psychosocial Stress Factors (PSF).ResultsHigh prevalence of problems was found for this sample: the CBCL showed 26.7% of clinical scores for Internalizing Problems, 40.6% for Externalizing Problems, and 40.6% for Total Problems. Exposure to family psychosocial stressors was also high, including severe disease (33%), physical aggression (28.9%), death (27.8%), psychiatric hospitalization (16.7%), suicide attempts (15.5%), and suicide (9.3%). Exposure to these family stressors was associated with an increase of two to four times in the prevalence of internalizing and externalizing problems.ConclusionsChildren exposed to substance abusers have more mental health problems than general population, even when compared to peers living in similar low-income areas. This is a group that should be target of a selective preventive intervention. 相似文献
74.
后脱钩时代,全国单项体育协会坚持依法自治不仅是"依法治体"的基本要求,而且也是脱钩改革有效落实的基本保证。针对全国单项体育协会存在的自治权性质界定不统一、非营利性属性规定不明确、体育行政权力异化、内部法人治理机制不健全的法治困境,从实体和程序上两方面来保障实现全国单项体育协会自治的法治化,以便真正实现单项协会的实体化,具体提出了单项协会自治主体性质的明确、相关法律规定的完善、非营利性标准的明晰界定等措施。 相似文献
75.
唐诗知识图谱的构建及其智能知识服务设计 总被引:2,自引:0,他引:2
[目的/意义]立足于当前大数据环境下的唐诗知识服务需求,以大规模唐诗数据为基础构建唐诗知识图谱并提供智能知识服务,推动人工智能环境下唐诗知识管理和知识服务方式的创新。[方法/过程]本文在对领域知识服务需求调研的基础上,设计领域知识服务驱动的唐诗本体模型,然后利用从Web上爬取的多源异构数据,采用知识抽取、知识融合、知识推理等技术自动构建唐诗知识图谱,统一表示和组织唐诗领域数据,实现对大规模唐诗数据的语义化处理。[结果/结论]本文设计基于唐诗知识图谱的智能知识服务平台KnowPoetry,提供唐诗领域的知识探索、时空轨迹、语义查询等智能化知识服务,推动人工智能环境下唐诗数字人文研究方法的创新转型。 相似文献
76.
ABSTRACTThe basic aim of this paper is to discuss the concept ‘Knowledge Democracy’ (KD) and what it can mean in the school context, its implications on knowledge production and dissemination and on the educational practices. We try to enrich this discussion by presenting action research projects to provide case studies of how thinking about KD can reshape educational practice. We consider that the discussion on KD has to be enriched as the concept seems very promising with good prospects towards school’s democratization. On the other hand, as it is quite new, it can encompass internal contradictions that can cause problems at the level of practice. So, we consider very important any contribution to this discussion not as another theoretical sample of the debate on the ‘politics of knowledge’, but because any improvement at the thinking of the issue can be reflected on school practices. Any challenge to traditional politics of knowledge can lead to a deeper understanding of the world of schooling and to transformations through new discourses and new approaches to teaching and learning in school. 相似文献
77.
Benjamin Rubeli Esther Oswald Achim Conzelmann Jürg Schmid Stefan Valkanover 《Physical Education & Sport Pedagogy》2020,25(4):346-360
ABSTRACTBackground: Schoolchildren’s personality development is considered a central goal of physical education (PE). With regard to the relationship between psychological well-being and global self-esteem over the life course, the promotion of positive self-esteem is an issue of particular significance. Past research revealed that PE taught with an individualized teacher frame of reference (iTFR) and a reflexive teaching style is associated with positive effects on facets of children’s perceived sports competence. However, it remains an open question whether this teaching styles has the potential to promote positive self-esteem.Purpose: The present study investigated whether a five-month teacher training, aimed to enhance the teachers’ iTFR and their reflexive teaching style in PE, has a positive effect on students’ perceived sports competence and their global self-esteem. To analyse the implementation quality, changes in students’ perceived iTFR and perceived reflexive teaching style were investigated.Method: A total of 21 teachers were assigned to either an intervention group (n?=?13), receiving the five-month teacher training, or a control group (n?=?8) consisting of regular teaching without teacher training. The teacher training encompassed five three-hour consecutive sessions during which the teachers acquired theoretical and practical knowledge about the promotion of competence perceptions in PE with a reflexive teaching style and an iTFR. Between the sessions, the teachers were instructed to implement an iTFR and a reflexive teaching style into their own PE classes. To evaluate the effects of the teacher training, their students’ (N?=?315, 53.7% girls, Mage?=?13.2 y, SDage?=?1.3 y) perceived teaching style (iTFR and reflexive teaching), perceived sports competence and global self-esteem were measured with paper-pencil questionnaires at three measurement points (pre, post and follow-up).Findings: Linear mixed effect models showed that students of the intervention group reported an increase in their teachers’ reflexive teaching style, but there were no changes with regard to iTFR. With regard to students’ perceived sports competence and global self-esteem, there were significant interaction effects between time and group over a period of eight months (from pre-test to follow-up), indicating positive effects on these self-concept dimensions due to the teacher training.Conclusion: The present study indicates that a long-term teacher training supports PE teachers to implement teaching styles with the aim to promote students’ self-concept. Furthermore, the findings lead to the assumption that a more pronounced iTFR in combination with an enhanced reflexive teaching style has the potential to positively influence schoolchildren’s perceived sports competence and global self-esteem. 相似文献
78.
朱玉霞 《河北体育学院学报》2020,34(1):37-42
运用双框架模型对中美竞技体育国际竞争力进行比较研究。认为:①从显现性框架分析,美国竞技体育国际竞争力一直稳定处于高位,而中国则呈现以2008年为峰顶的倒“U”型发展特征,且与美国还存在一定差距;②从解释性框架分析,美国竞技体育国际竞争力已趋于顶峰,而中国稳步提升;③中国竞技体育发展潜力巨大,但短时间内难以赶超美国;④“举国体制”有利于中国竞技体育显现性竞争力的提升,但与美国社会办竞技体育的发展模式相比,市场、社会在竞技体育发展中的作用发挥不足,不利于高经济性项目、高欣赏性项目的发展;⑤坚持“举国体制”、承办2022年冬奥会有利于中国竞技体育显现性竞争力的提升和冬季项目的发展,但同样存在竞技体育项目布局转型的困难和群众体育基础薄弱的困境。 相似文献
79.
Alice A. Bamigbola Airen E. Adetimirin 《International Information and Library Review》2020,52(2):95-107
AbstractInstitutional repositories (IRs) present platform to disseminate research findings to complement the traditional scholarly communication model. The use of IRs is beneficial to authors, host institutions, libraries and society at large. Despite the numerous benefits of IRs, there is low deposit of scholarly works by lecturers and the investment on IRs seems to be a waste. This study examined determinants of perceived ease of use (PEOU) of IRs by lecturers in Nigerian universities. A survey of lecturers received 857 respondents. Awareness, anchor and adjustment factors were found to be determinants of PEOU of Institutional repositories by lecturers in Nigerian Universities. 相似文献
80.
Hans-Christoph Koller 《Educational theory》2020,70(5):633-651
In this essay, Hans-Christoph Koller presents a concept of transformational processes of Bildung in an attempt to redefine the German notion of Bildung referring to actual social conditions of educational processes. According to this conception, Bildung is a transformation of world- and self-relations that can come about when subjects are confronted with problems for which they have no established routines of engagement. With reference to theories of Pierre Bourdieu, Bernhard Waldenfels, and Ulrich Oevermann, Koller looks for answers to three questions: (1) Which concepts and theories are able to adequately grasp the world- and self-relations of subjects going through processes of Bildung? (2) How can the problems that trigger processes of Bildung and that challenge subjects to transform be determined more precisely? (3) How exactly does the emergence of new figures of world- and self-relations take place when we “successfully” complete a process of Bildung? Finally, the essay concludes with an attempt to clarify the normative implications of this theory. 相似文献