6,170 research outputs found

    Expanding Einstein-Yang-Mills by Yang-Mills in CHY frame

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    Using the Cachazo-He-Yuan (CHY) formalism, we prove a recursive expansion of tree level single trace Einstein-Yang-Mills (EYM) amplitudes with arbitrary number of gluons and gravitons, which is valid for general spacetime dimensions and any helicity configurations. The recursion is written in terms of fewer-graviton EYM amplitudes and pure Yang-Mills (YM) amplitudes, which can be further carried out until we reach an expansion in terms of pure YM amplitudes in Kleiss-Kuijf (KK) basis. Our expansion then generates naturally a spanning tree structure rooted on gluons whose vertices are gravitons. We further propose a set of graph theoretical rules based on spanning trees that evaluate directly the pure YM expansion coefficients.Comment: 36 pages, 3 captioned figures; v2: more details added, revised and published versio

    Understanding changes in teacher beliefs and identity formation: A case study of three novice teachers in Hong Kong

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    Novice teachers often undergo an identity shift from learner to teacher. Along this process, their instructional beliefs change considerably which in turn affect their teacher identity formation. Drawing on data collected mainly through interviews with three novice English teachers formore than one year, the present study examines their firstyear teaching experience in Hong Kong secondary schools, focusing on changes of their English teaching beliefs and the impact of these changes on their identity construction. Findings reveal that while the teachers’ initial teaching beliefs were largely shaped in their prior school learning and learning-to-teach experience, these beliefs changed and were reshaped a great deal when encountering various contextual realities, and these changes further influenced their views on their teacher identity establishment, unfortunately in a more negative than positive direction. The study sheds light on the importance of institutional support in affording opportunities for novice teachers’ workplace learning and professional development

    The effects of word exposure frequency on incidental learning of the depth of vocabulary knowledge

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    This study examined the rate at which depth of vocabulary knowledge was learned and retained from reading a 300-headword graded reader, The Star Zoo. A total of 30 tertiarylevel students who learn English as a foreign language (EFL) in China volunteered to take part in a reading program. Incidental learning and retention of the depth of vocabulary knowledge was measured, complementing previous research along this line. The depth of vocabulary knowledge was examined by using 36 test items within six bands of frequency (more than 20 times to only once). The target words were substituted with pseudo-words. Two tests were employed to measure receptive and productive vocabulary knowledge. This study was completed in three sessions: Students read the book for the first time and finished tests; students read the book for the second time seven days later, and finished tests; finally, retention tests were completed three months later. The findings showed that incidental vocabulary learning through reading was very limited, and this learning was largely based on a high frequency of word occurrence, that is, the higher the frequency level was, the better the learners’ word-learning was. The number of times that Chinese EFL learners needed to encounter a word to recognize vocabulary knowledge was 14 times, and at least 18 times were needed for productive vocabulary knowledge. This study shows that attention to building knowledge of known words instead of solely introducing new words should be paid, and that both word exposure frequency and elaborate word processing are important as part of successful vocabulary development

    Strategies for teaching and learning vocabulary

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    Abstract This article presents an overview of current research on second language vocabulary learning and proposes eight strategies for teaching and learning vocabulary. First, to facilitate effective vocabulary teaching, choosing high-frequency words is essential. Teachers of vocabulary also need to add explicit, intentional teaching to incidental learning. In addition, vocabulary learning strategies including morphological awareness and lexical inference provides a platform by which learners can improve both receptive and productive vocabulary knowledge. This article also suggests that productive vocabulary knowledge needs more attention than receptive vocabulary knowledge, and that available textbooks seldom address vocabulary sufficiently. In summary, it is very important for all learners and teachers to acknowledge that learning vocabulary is incremental in nature, and we should develop a principled, long-term program for teaching and learning vocabulary

    Involvement Load in Translation Tasks and EFL Vocabulary Learning

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    This study mainly examined the effects of three translation tasks on vocabulary learning for tertiary-level learners based on the motivational-cognitive constructs of task-induced involvement load, as suggested in the Involvement Load Hypothesis (ILH) (Laufer & Hulstijn, 2001). Sixty low-proficiency level students were randomly assigned to three groups to complete one of three translation tasks that varied in the amount of involvement load: Task 1, translation-only mode (one involvement load), translation plus fill-in exercises (two involvement load), and translation plus sentence writing (three involvement load). Three-modality vocabulary knowledge of recognizing word form, recalling meaning, and producing word knowledge were measured immediately after study and two months after study. The results of the study were in line with the claims of ILH that word learning and retention in a second language are contingent upon a task’s involvement load. In the current study, word learning and retention was highest in Task 3, followed by Task2, and Task 1. These and relevant pedagogical implications were discussed.

    An Output Task of English Drama Performance and its Effects on Incidental L2 Vocabulary Learning: An Experimental Study

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    This pedagogical practice described in this study is to analyze L2 learners’ attitude and vocabulary outcomes based on an output task of introducing English drama performance into classroom teaching. In the controversial context of Swain's (1985) ‘output Hypothesis’ and Krashen’s (1985) ‘input hypothesis’, this paper discusses the rational, motivation, and ramifications of joining this output task study. It can be learned from the study that almost one third of learners lost motivation and interest after this task. When divided the participants into three groups of HPL, IL and LL. The former two groups performed better in vocabulary gain post this task and sustain a good retention in target words after two months. The LL group performed a relatively unexpected low result in vocabulary learning. The reason assumed for this is that the acceptability and processability of materials for this task is crucial for learners to modify original output to reprocessed forms of using target words which determines whether they could benefit or not from this task. This study also suggests part of the findings is compatible with Swain's (1985) ‘output Hypothesis’. Keywords: task, output, motivation, acceptability, processability, vocabulary gai

    Assessing Learner Autonomy and EFL Vocabulary Acquisition: A Case Study

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    The importance of autonomy learning is widely acknowledged in teaching English as a Foreign Language (EFL) in Asian contexts. The present study attempted to report low proficiency level students’ autonomous vocabulary learning. The first part of the present study focused on exploring how learners perceived and experienced their autonomous vocabulary learning, with a questionnaire and group discussion applied to collect data. During the second part of the study, the data were discussed collaboratively by six teachers to identify the different approaches utilized by learners. Priorities included setting weekly goals, self-planning and self-monitoring the process of learning vocabulary. Results also revealed that a weak ‘top-down’ approach in implementing learner autonomy is inadequate. Teachers need to provide scaffolding skills tailored to learners’ context-specific needs, for which a strong ‘bottom-up’ approach is more appropriate in supporting autonomous learning. In this case, classroom time should be allocated to demonstrate the strategies and teachers should work collaboratively to develop resources and materials for learners’ autonomous vocabulary learning. The present study also addressed the need for establishing an effective intervention for supporting learner autonomy. Keywords: learner autonomy, vocabulary learning, self-plan, self-monito

    Assessing Learner Autonomy and EFL Vocabulary Acquisition: a Case Study

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    The importance of autonomy learning is widely acknowledged in teaching English as a Foreign Language (EFL) in Asian contexts. The present study attempted to report low proficiency level students\u27 autonomous vocabulary learning. The first part of the present study focused on exploring how learners perceived and experienced their autonomous vocabulary learning, with a questionnaire and group discussion applied to collect data. During the second part of the study, the data were discussed collaboratively by six teachers to identify the different approaches utilized by learners. Priorities included setting weekly goals, self-planning and self-monitoring the process of learning vocabulary. Results also revealed that a weak ‘top-down\u27 approach in implementing learner autonomy is inadequate. Teachers need to provide scaffolding skills tailored to learners\u27 context-specific needs, for which a strong ‘bottom-up\u27 approach is more appropriate in supporting autonomous learning. In this case, classroom time should be allocated to demonstrate the strategies and teachers should work collaboratively to develop resources and materials for learners\u27 autonomous vocabulary learning. The present study also addressed the need for establishing an effective intervention for supporting learner autonomy. Keywords: learner autonomy, vocabulary learning, self-plan, self-monito

    Emotional Development and Construction of Teacher Identity: Narrative Interactions about the Pre-service Teachers’ Practicum Experiences

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    Pre-service teacher identity research has directed limited attention to the construction and development of professional teacher identity through narrative interaction. An analysis of narrative interactions among pre-service teachers in the present study explored the ways in which they negotiated emotional flux in the process of training to become a teacher. Overall, findings show that emotional flux and identity change are connected, and hidden ‘emotional rules’ are embedded in the teaching practicum. The pre-service teachers’ negative emotions gradually escalated due to contextual constraints, hierarchical structures, and lack of support from their mentors. This escalation diminished the development of their teacher identity. However, increasing recognition and progress by their students can stimulate pre-service teachers to perceive their assumed roles and reconstruct professional identity. Within the context of exploring this interconnection between teacher emotions and teacher identity, the present study argues that narrative interaction can complement existing knowledge on the subject
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