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1.
Semantic knowledge accumulates through explicit means and productive processes (e.g., analogy). These means work in concert when information explicitly acquired in separate episodes is integrated, and the integrated representation is used to self-derive new knowledge. We tested whether (a) self-derivation through memory integration extends beyond general information to science content, (b) self-derived information is retained, and (c) details of explicit learning episodes are retained. Testing was in second-grade classrooms (children 7–9 years). Children self-derived new knowledge; performance did not differ for general knowledge (Experiment 1) and science curriculum facts (Experiment 2). In Experiment 1, children retained self-derived knowledge over one week. In Experiment 2, children remembered details of the learning episodes that gave rise to self-derived knowledge; performance suggests that memory integration is dependent on explicit prompts. The findings support nomination of self-derivation through memory integration as a model for accumulation of semantic knowledge and inform the processes involved.  相似文献   
2.
侯爽 《体育科研》2019,(3):30-37
“体教结合”是解决当前我国竞技体育发展问题的重要途径和举措。传统的体育后备人才培养模式只重视专项体育技能的发展而忽视了文化教育的重要性,不利于个体的全面发展。“体教结合”更重视人的全面发展,体育与教育的融合,使得竞技体育人才逐渐从运动员这一单一角色向“学生-运动员”双重角色转变。研究以角色认同为切入口,探讨上海“体教结合”举措下,角色的转变对体育竞技后备人才的影响。选取上海体育学院中国乒乓球学院少年班学员作为“学生-运动员”样本,选取国家乒乓球青年队及部分省市队队员作为职业运动员样本,使用结构化心理测量工具,对比两类受访者在运动与学业上的角色认同、心理倦怠与动机变量的差异。得出:在上海“体教结合”举措下,竞技体育后备人才认同“学生-运动员”双重角色,他们在学业任务中的卷入程度更高;双重角色使运动员在运动任务与学业任务上的主观价值感存在差异,表现出双重角色之间的冲突,但对个体的整体人生规划并不冲突;双重角色之间的转化,对于“学生-运动员”的心理健康存在促进效应。  相似文献   
3.
Distant supervision (DS) has the advantage of automatically generating large amounts of labelled training data and has been widely used for relation extraction. However, there are usually many wrong labels in the automatically labelled data in distant supervision (Riedel, Yao, & McCallum, 2010). This paper presents a novel method to reduce the wrong labels. The proposed method uses the semantic Jaccard with word embedding to measure the semantic similarity between the relation phrase in the knowledge base and the dependency phrases between two entities in a sentence to filter the wrong labels. In the process of reducing wrong labels, the semantic Jaccard algorithm selects a core dependency phrase to represent the candidate relation in a sentence, which can capture features for relation classification and avoid the negative impact from irrelevant term sequences that previous neural network models of relation extraction often suffer. In the process of relation classification, the core dependency phrases are also used as the input of a convolutional neural network (CNN) for relation classification. The experimental results show that compared with the methods using original DS data, the methods using filtered DS data performed much better in relation extraction. It indicates that the semantic similarity based method is effective in reducing wrong labels. The relation extraction performance of the CNN model using the core dependency phrases as input is the best of all, which indicates that using the core dependency phrases as input of CNN is enough to capture the features for relation classification and could avoid negative impact from irrelevant terms.  相似文献   
4.
Community question answering (CQA) services that enable users to ask and answer questions are popular on the internet. Each user can simultaneously play the roles of asker and answerer. Some work has aimed to model the roles of users for potential applications in CQA. However, the dynamic characteristics of user roles have not been addressed. User roles vary over time. This paper explores user representation by tracking user-role evolution, which could enable several potential applications in CQA, such as question recommendation. We believe this paper is the first to track user-role evolution and investigate its influence on the performance of question recommendation in CQA. Moreover, we propose a time-aware role model (TRM) to effectively track user-role evolution. With different independence assumptions, two variants of TRM are developed. Finally, we present the TRM-based approach to question recommendation, which provides a mechanism to naturally integrate the user-role evolution with content relevance between the answerer and the question into a unified probabilistic framework. Experiments using real-world data from Stack Overflow show that (1) the TRM is valid for tracking user-role evolution, and (2) compared with baselines utilizing role based methods, our TRM-based approach consistently and significantly improves the performance of question recommendation. Hence, our approach could enable several potential applications in CQA.  相似文献   
5.
Introduction: Social roles in physical education (PE) classes have been much studied, especially mentoring and coaching roles. The studies have shown that mentoring and coaching are beneficial not only for motor learning, but also for methodological and social learning. To our knowledge, the role of the student referee in PE lessons has never been specifically studied. Yet refereeing is essential in many sports, including team sports, and provides an experience of responsibility that many teachers want to offer their students. Encouraging students to take on this role can nevertheless be difficult.

Objective: The objective of the present study was to gain access to students’ lived experiences as referees in order to determine their strategies for being effective. We particularly wanted to determine which concerns organized their activity so that we could identify a refereeing typology that would be useful for PE teaching. Our study is original in that we did not rely exclusively on experiential data to understand student refereeing activity. We also collected data on the students’ motivation in order to better understand their experiences. For this purpose, the study was conducted within the methodological framework of course-of-action theory and self-determination theory.

Method: Seventy-four students from three classes in the third year of middle school (about 13 years old) participated in the study. Among them, four (two girls and two boys and not experts in the sports in which they were going to referee) had volunteered to be filmed and to participate in self-confrontation interviews. The other students completed two questionnaires to provide information on their motivation for refereeing. The situations studied were basketball and handball matches held at the end of the lessons.

Two categories of data were collected: qualitative and quantitative. The qualitative data were based on audiovisual recordings of the students as they refereed matches and verbalization data from self-confrontation interviews; these data were used to document the students’ courses of experience during the activity period under study. The quantitative data were collected using two questionnaires, one to assess the determinants of motivation and the other to assess self-determined motivation.

Results and discussion: The qualitative analysis highlighted three typical student involvements: fulfilling the role of referee, getting help, and occasionally dropping out of the role. The quantitative analysis revealed that the students in the social role of referee mainly expressed amotivation, external regulation, and intrinsic motivation toward knowledge and accomplishment.

The results are discussed around two major points: (1) the students’ strategies of alternation from which their refereeing activity emerged and (2) proposals for PE teacher interventions.  相似文献   

6.
[目的/意义]微信群内部会话交流过程存在着复杂的网络结构,探究微信群内部网络结构特征并划分成员角色对研究微信群中信息传播及成员角色关系具有重要意义。[方法/过程]以虚拟社区理论和会话分析理论为基础,以真实微信群内部的会话数据作为研究对象,通过构造成员活跃度划分微信群成员角色类型,基于成员相互回应行为与共同回应行为设计成员关联强度算法并构建会话交流网络,采用社会网络分析和内容分析方法对其静态结构特征及动态结构演化进行分析。[结果/结论]微信群内部成员角色及地位具有差异性,会话交流过程呈现出明显的中心性态势;微信群会话交流网络符合六度分割理论,具有小世界效应的特征;微信群会话交流网络具有动态演化性且核心成员具有时间依赖性。  相似文献   
7.
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   
8.
傅柱  曹猛  王曰芬  徐绪堪 《现代情报》2018,38(10):16-23
以设计过程为视角,探讨概念设计知识管理中知识流的内涵、特征和机理。结合知识流理论和SECI模型,依据概念设计过程分析概念设计中知识流的内容和流动模式;在知识流建模相关研究的基础上,对概念设计中的知识流节点进行分析和建模;基于角色模型分析角色与工作流、知识流之间的映射过程。根据概念设计过程,分析并揭示了概念设计中需求确认、总体方案设计、总体方案求解、方案评价和决策4个主要步骤的知识流动机制;对概念设计的知识流节点进行建模,按照知识汇集模式将概念设计知识流分为连续知识流、合并知识流、拆分知识流、广播知识流、循环知识流5类,按照知识传递模式将概念设计知识流可分为经验知识流、协作知识流、援助知识流3类;提出概念设计中基于角色模型的工作流和知识流整合模型,并以反后坐系统概念设计为例进行模型验证。通过本文分析和建模,能够在一定程度上揭示概念设计中知识流的内涵和机理。  相似文献   
9.
The proposed work aims to explore and compare the potency of syntactic-semantic based linguistic structures in plagiarism detection using natural language processing techniques. The current work explores linguistic features, viz., part of speech tags, chunks and semantic roles in detecting plagiarized fragments and utilizes a combined syntactic-semantic similarity metric, which extracts the semantic concepts from WordNet lexical database. The linguistic information is utilized for effective pre-processing and for availing semantically relevant comparisons. Another major contribution is the analysis of the proposed approach on plagiarism cases of various complexity levels. The impact of plagiarism types and complexity levels, upon the features extracted is analyzed and discussed. Further, unlike the existing systems, which were evaluated on some limited data sets, the proposed approach is evaluated on a larger scale using the plagiarism corpus provided by PAN1 competition from 2009 to 2014. The approach presented considerable improvement in comparison with the top-ranked systems of the respective years. The evaluation and analysis with various cases of plagiarism also reflected the supremacy of deeper linguistic features for identifying manually plagiarized data.  相似文献   
10.
《Sport Management Review》2019,22(1):142-152
To reach and include socially vulnerable people through sport, it is important to create partnerships between sports organisations and public health organisations (i.e., sport-for-health partnerships). Working in sport-for-health partnerships is challenging, however, and little is known about how to manage such partnerships. To explore possible predictors of successful sport-for-health partnership, the authors administered a questionnaire among 86 participants in Dutch sport-for-health partnerships. The questionnaire included measures pertaining to three indicators of successful inter-sectoral partnership (i.e., partnership synergy, partnership sustainability, and community outcomes) and nine partnership elements that may predict its success. Multivariate results suggest that (a) partnership synergy may be best predicted by communication structure and building on the partnership participants’ capacities, (b) community partnership outcomes may be best predicted by partnership visibility and task management, and (c) partnership sustainability may be best predicted by partnership visibility. Hence, the authors would recommend actors in sport-for-health partnerships to pay particular attention to communication structure, building on capacities, visibility, and task management.  相似文献   
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