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991.
《师资教育杂志》2012,38(1):3-4
This article reports on In‐Service Education and Training (INSET) workshops offered in Limpopo and Mpumalanga Provinces in the field of environmental education. The purpose of these workshops is to assist practising teachers to enhance their teaching skills, to infuse environmental education in their teaching and to participate in solving environmental problems in their communities. Aspects of the workshops were assessed using a questionnaire which was completed by teachers on conclusion of the workshops. These data are provided as well as recommendations provided by the attendees. Although this is a case study report where findings are usually not perceived to be generalisable, it is believed that the participants' perceptions of and recommendations for improving INSET opportunities could substantially inform similar INSET initiatives.  相似文献   
992.
993.
One of the most important opinion mining research directions falls in the extraction of polarities referring to specific entities (aspects) contained in the analyzed texts. The detection of such aspects may be very critical especially when documents come from unknown domains. Indeed, while in some contexts it is possible to train domain-specific models for improving the effectiveness of aspects extraction algorithms, in others the most suitable solution is to apply unsupervised techniques by making such algorithms domain-independent and more efficient in a real-time environment. Moreover, an emerging need is to exploit the results of aspect-based analysis for triggering actions based on these data. This led to the necessity of providing solutions supporting both an effective analysis of user-generated content and an efficient and intuitive way of visualizing collected data. In this work, we implemented an opinion monitoring service implementing (i) a set of unsupervised strategies for aspect-based opinion mining together with (ii) a monitoring tool supporting users in visualizing analyzed data. The aspect extraction strategies are based on the use of an open information extraction strategy. The effectiveness of the platform has been tested on benchmarks provided by the SemEval campaign and have been compared with the results obtained by domain-adapted techniques.  相似文献   
994.
This study tackles the problem of extracting health claims from health research news headlines, in order to carry out veracity check. A health claim can be formally defined as a triplet consisting of an independent variable (IV – namely, what is being manipulated), a dependent variable (DV – namely, what is being measured), and the relation between the two. In this study, we develop HClaimE, an information extraction tool for identifying health claims in news headlines. Unlike the existing open information extraction (OpenIE) systems that rely on verbs as relation indicators, HClaimE focuses on finding relations between nouns, and draws on the linguistic characteristics of news headlines. HClaimE uses a Naïve Bayes classifier that combines syntactic and lexical features for identifying IV and DV nouns, and recognizes relations between IV and DV through a rule-based method. We conducted an evaluation on a set of health news headlines from ScienceDaily.com, and the results show that HClaimE outperforms current OpenIE systems: the F-measures for identifying headlines without health claims is 0.60 and that for extracting IV-relation-DV is 0.69. Our study shows that nouns can provide more clues than verbs for identifying health claims in news headlines. Furthermore, it also shows that dependency relations and bag-of-words can distinguish IV-DV noun pairs from other noun pairs. In practice, HClaimE can be used as a helpful tool to identifying health claims in news headlines, which can then be further compared against authoritative health claims for veracity. Given the linguistic similarity between health claims and other causal claims, e.g., impacts of pollution on the environment, HClaimE may also be applicable for extracting claims in other domains.  相似文献   
995.
This research presents an enhanced approach for Aspect-Based Sentiment Analysis (ABSA) of Hotels’ Arabic reviews using supervised machine learning. The proposed approach employs a state-of-the-art research of training a set of classifiers with morphological, syntactic, and semantic features to address the research tasks namely: (a) T1:Aspect Category Identification, (b) T2:Opinion Target Expression (OTE) Extraction, and (c) T3: Sentiment Polarity Identification. Employed classifiers include Naïve Bayes, Bayes Networks, Decision Tree, K-Nearest Neighbor (K-NN), and Support-Vector Machine (SVM).The approach was evaluated using a reference dataset based on Semantic Evaluation 2016 workshop (SemEval-2016: Task-5). Results show that the supervised learning approach outperforms related work evaluated using the same dataset. More precisely, evaluation results show that all classifiers in the proposed approach outperform the baseline approach, and the overall enhancement for the best performing classifier (SVM) is around 53% for T1, around 59% for T2, and around 19% in T3.  相似文献   
996.
In addressing persistent gaps in existing theories, recent advances in data-driven research approaches offer novel perspectives and exciting insights across a spectrum of scientific fields concerned with technological change and the socio-economic impact thereof. The present investigation suggests a novel approach to identify and analyze the evolution of technology sectors, in this case, information and communications technology (ICT), considering international collaboration patterns and knowledge flows and spillovers via information inputs derived from patent documents.The objective is to utilize and explore information regarding inventors’ geo-location, technology sector classifications, and patent citation records to construct various types of networks. This, in turn, will open up avenues to discover the nature of evolutionary pathways in ICT trajectories and will also provide evidence of how the overall ICT knowledge space, as well as directional knowledge flows within the ICT space, have evolved differently. It is expected that this data-driven inquiry will deliver intuitive results for decision makers seeking evidence for future resource allocation and who are interested in identifying well-suited collaborators for the development of potential next-generation technologies. Further, it will equip researchers in technology management, economic geography, or similar fields with a systematic approach to analyze evolutionary pathways of technological advancements and further enable exploitation and development of new theories regarding technological change and its socio-economic consequences.  相似文献   
997.
BackgroundIn order to prevent child abuse, instruments measuring child abuse potential (CAP) need to be appropriate, reliable and valid.ObjectiveThis study aimed to confirm the 6-factor structure of the Brief Child Abuse Potential Inventory (BCAPI) in a German sample of mothers and fathers, and to examine longitudinal predictors of CAP.Participants and settingTwo waves of data were collected from 197 mothers and 191 fathers of children aged 10–21 months for the “Kinder in Deutschland – KiD 0–3” in-depth study. Families were stratified based on prior self-report data for screening purposes.Methods138 fathers and 147 mothers were included in the analysis (invalid: 25% mothers, 30% fathers). First, validity of reporting was examined. Second, confirmatory factor analysis (CFA) was employed to assess factor structure. Third, internal reliability and criterion validity were examined. Finally, multivariate poisson regressions investigated longitudinal predictors of CAP in mothers.ResultsA previously established six-factor structure was confirmed for mothers but not fathers. CFA failed for fathers due to large numbers of variables with zero variance. For mothers, internal consistency and criterion validity were good. BCAPI score at follow-up was associated with baseline BCAPI score (β = 00.08), stress (β = 0.06), education (β=-0.19) and alcohol use (β = .58).ConclusionsFindings confirm the six-factor structure of the BCAPI among German mothers. The clinical use of the BCAPI in fathers is not recommended as it might produce data that are hard to interpret. Further research with fathers is needed to establish if this is due to limitations with this dataset or with the questionnaire.  相似文献   
998.
Graph-based recommendation approaches use a graph model to represent the relationships between users and items, and exploit the graph structure to make recommendations. Recent graph-based recommendation approaches focused on capturing users’ pairwise preferences and utilized a graph model to exploit the relationships between different entities in the graph. In this paper, we focus on the impact of pairwise preferences on the diversity of recommendations. We propose a novel graph-based ranking oriented recommendation algorithm that exploits both explicit and implicit feedback of users. The algorithm utilizes a user-preference-item tripartite graph model and modified resource allocation process to match the target user with users who share similar preferences, and make personalized recommendations. The principle of the additional preference layer is to capture users’ pairwise preferences, provide detailed information of users for further recommendations. Empirical analysis of four benchmark datasets demonstrated that our proposed algorithm performs better in most situations than other graph-based and ranking-oriented benchmark algorithms.  相似文献   
999.
In the last decades, many similarity measures are proposed, such as Jaccard coefficient, cosine similarity, BM25, language model, etc. Despite the effectiveness of the existing similarity measures, we observe that none of them can consistently outperform the others in most typical situations. Choosing which similarity predicate to use is usually treated as an empirical question by evaluating a particular task with a number of different similarity predicates, which is not computationally efficient and the obtained results are not portable. In this paper, we propose a novel approach to combine different similarity predicates together to form a committee so that we do not need to worry about choosing which of them to use. Empirically, we can obtain a better result than any individual similarity predicate, which is quite meaningful in practice. Specifically, our method models the problem of committee generation as a 0–1 integer programming problem based on the confidence of similarity predicates and the reliability of attributes. We demonstrate the effectiveness of our model by applying it on three datasets with controlled errors. Experimental results demonstrate that our similarity predicate committee is more robust and superior over existing individual similarity predicates.  相似文献   
1000.
Automatic text summarization attempts to provide an effective solution to today’s unprecedented growth of textual data. This paper proposes an innovative graph-based text summarization framework for generic single and multi document summarization. The summarizer benefits from two well-established text semantic representation techniques; Semantic Role Labelling (SRL) and Explicit Semantic Analysis (ESA) as well as the constantly evolving collective human knowledge in Wikipedia. The SRL is used to achieve sentence semantic parsing whose word tokens are represented as a vector of weighted Wikipedia concepts using ESA method. The essence of the developed framework is to construct a unique concept graph representation underpinned by semantic role-based multi-node (under sentence level) vertices for summarization. We have empirically evaluated the summarization system using the standard publicly available dataset from Document Understanding Conference 2002 (DUC 2002). Experimental results indicate that the proposed summarizer outperforms all state-of-the-art related comparators in the single document summarization based on the ROUGE-1 and ROUGE-2 measures, while also ranking second in the ROUGE-1 and ROUGE-SU4 scores for the multi-document summarization. On the other hand, the testing also demonstrates the scalability of the system, i.e., varying the evaluation data size is shown to have little impact on the summarizer performance, particularly for the single document summarization task. In a nutshell, the findings demonstrate the power of the role-based and vectorial semantic representation when combined with the crowd-sourced knowledge base in Wikipedia.  相似文献   
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