Finite Control Set Model Predictive Control with Feedback Correction for Power Converters

As an open-loop model predictive control algorithm,finite control set model predictive control(FCS-MPC)scheme in power converter system is based on assumption that responses of optimal control implemented on prediction model agree well with actual system.The influence of model parameter mismatches and environment disturbance on control performance of scheme is neglected.Then,based on feedback correction strategy in traditional model predictive control algorithm,we derive a finite control set model predictive control with feedback correction scheme(FCS-MPCFC)that allows us to adjust prediction model output at current instant by model prediction error at previous instant,and the closed-loop correction of prediction model output is achieved.Simulations comparison analyses on a two-level three-phase inverter with multi-type model parameter mismatches controlled by traditional and improved FCS-MPC scheme are presented.Experiments are carried out on DSP controller platform.

Discussion about the Side Effect of Error Corrective Feedback and Possible Alternatives to Error Correction

Feedbacks given by teachers is possibly a common instruction in second language writing classes, to help students makeprogress in writing. At one time, feedback was almost entirely at a superficial level--identifying the grammatical errors and givingthe correct form. However, recently, this type of feedback has begun to be challenged by some researchers(eg.,Krashen, 1984, Trus-cott, 1996),who argue that teachers should be more concerned with the content of essay instead of grammatical errors. This essaywill discuss some research surrounding feedback to students' writing and will try to find the answer to the question whether the er-ror corrective feedback should be abandoned. In order to find the answer, the essay will elaborate on two parts: some literary reviewabout the issue and some suggested solutions to the issue.

Teachers' Oral Corrective Feedback and Its Influence on Learner Uptake in the Classes of Teaching English as a Foreign Language for Minority Students in Xinjiang Junior High Schools

The present study explored the features and the effectiveness of teachers' oral CF in the classrooms of Teaching English as a Foreign Language(TEFL) for minority students in Xinjiang junior high schools. The analytical framework of this study consulted Lyster's(1998) coding scheme. 720 minutes of classroom observation were recorded and transcribed. The database was coded and the distribution of errors, CF and uptake was analyzed.

The Role of Non-verbal Behavior of Teachers in Providing Students Corrective Feedback and Their Consequences

Considering the primary focus of corrective feedback literature on verbal-correction provided by teachers and lack of attention to the role of other forms of corrective feedback in FL （foreign language） classroom interaction, this paper demonstrates how essential teachers＇ non-verbal communication and stance display are in making students＇ errors noticeable for them by providing samples from videotaped data. The findings in this study provide insights into the use of non-verbal behavior in providing students with corrective feedback. This study shows that research dealing only with verbal corrections provided by FL teachers cannot fully define the classroom interaction in terms of teachers＇ use of error correction techniques and student notification and uptake.

Effects of Written Corrective Feedback on College EFL Students’Writing Accuracy and Linguistic Knowledge Acquisition

Set at the interface between second language acquisition and second language writing,this study examines how different types of written corrective feedback(WCF)influence the writing accuracy of Chinese college students learning English as a Foreign Language(EFL)and whether WCF facilitates the students’grasp of the focused linguistic knowledge.The participants(n=60)were divided into direct correction group(n=20),indirect error-coding group(n=20)and metalinguistic explanation group(n=20).The three groups wrote four essays in two months and received WCF for the first three essays on the five targeted error types,namely tense errors,confusion of different forms of a word,word(articles,prepositions,etc.)missing,errors in subjectverb agreement and inappropriate verb-noun collocations.The results show that all three types of WCF improved students’writing accuracy but none of them had any statistical advantage,and the metalinguistic WCF was more effective than the other two forms in facilitating the acquisition of the targeted linguistic features.These results shed some light on teaching and consolidation of language points through writing in EFL contexts.

Macao Secondary School EFL Teachers' Perspectives on Written Corrective Feedback: Rationales and Constraints

Corrective feedback on writing(WCF)has been one of the most controversial topics in ESL/EFL teaching.In the past decades,much has been disputed regarding the effectiveness and preferences of the quantity,focus,directness and source of WCF.With so much uncertainty,the researcher set out to investigate how research-informed secondary school teachers in Macao reported their beliefs,rationales,practices and constraints of administering corrective feedback for EFL writing in Macao secondary schools.Twelve secondary school teachers were recruited at a TESOL conference to conduct focus-group discussions.Similar to previous findings,results suggest teachers had clear rationales as to their ways of practising WCF.However,many expressed difficulties in acting according to rationales and beliefs.Despite their experience and knowledge,practical constraints such as school policies and teacher workload made it unlikely for them to follow their thoughts with feedback on writing.This study identified six sources of constraints that could prohibit practices and potentially reshape ones’beliefs,which sheds light on future directions of WCF research.

Achieving Self-Imitation for English Intonation Learning:The Role of Corrective Feedback

Corrective feedback is crucial for pronunciation teaching.However,in current pronunciation teaching practice,the corrective feedback provided usually fails to locate pronunciation problems and inform learners of the differences between their mispronunciations and the correct form.Based on the motor theory,this study attempted to explore a new way of corrective feedback for pronunciation teaching.Specifically,the learners’ speech output was modified and then was played back to them as an input model for learning.In this way,the learners can imitate the pronunciation model of their own voices,achieving self-imitation.This study included two experiments.The first explored the viability of obtaining one’s self-perceived voice through delayed feedback paradigm.The second experiment examined the effectiveness of self-imitation for English intonation learning.Results showed that imitating the pronunciation model of one’s own voice can reduce the learners’ phonological memory load,assist critical listening and facilitate accurate phonetic realizations of the target intonation.

Is Recast the Most Effective Type of Corrective Feedback？ --Under Cognitive and Sociolinguistic Approach

Currently, there are a variety of researches on corrective feedback, especially on recasts. Most of researches are experiment-based and depend on the certain context. This paper addresses the question of ＂Is recast the most effective form of corrective feedback？＂ by two of Second Language Acquisition （SLA） approaches： cognitive approach and sociolinguistic approach. Empirical research will be used as complement. Theoretically speaking, SLA hypotheses in cognitive approach exist disagreements. Interaction hypothesis favors recast while both input hypothesis and output hypothesis doubt the effectiveness of it. Sociolinguistic approach underscores the significance of appropriate and timely corrective feedback and does not give more credit to certain strategy. Both approaches provide the pedagogical implications and elements to take into account for adopting recasts.

The Effect of Different Types of Corrective Feedback on L2 Writing Accuracy of college students

Since the process writing was raised in the L2 writing in 1970s, the feedback has been an important part of teaching. A range of researchers have investigated the effect of different types of error feedback to find whether the feedback can help L2 writers improve the accuracy of their writing. Similar to the previously discussed question, they have also reached rather controversial conclusions. Most often, these studies have categorized corrective feedback as either direct or indirect. To explore the effects of corrective feedback in L2 writing, the paper investigated the types of feedback given to 30 college students of Tianhe College in Guangdong province. The study improved that correction feedback can improve accuracy in student writing.

The Application of Corrective Feedback Theory in Integrated English Course

Integrated English Course in Chinese universities serves a group of non-English major students for the main educational training purpose of second language learning together with language learning skills development under different unit themes.In the process of learning another language,as language leaners,making mistakes is natural and inevitable.This procedure of making mistakes and correcting mistakes contribute to the gradual improvement from a starter to an advanced learner.Encountering mistakes made in various conditions in the classroom,teachers need to form proper awareness,and give appropriate feedback.

Research on Corrective Feedback in Foreign Language Teaching

Corrective feedback is an important part of second language acquisition, and many researches have showed that the corrective feedback in general have a positive effect on second language acquisition. The present study aims to investigate corrective feedback and draw enlightening conclusions:1) Different corrective feedback types have different effects on second language acquisition; 2)The effect of corrective feedback is also influenced by the feedback timing, explicitness of the feedback and learners' individual differences; 3) Teachers should consider feedback types, feedback timing, and individual differences of students based on teaching contents when providing corrective feedback in foreign language teaching.

The Effects of Learner’s Individual Differences on the Written Corrective Feedback

From the perspective of individual learner differences,this paper aims to show the readers an outline of the influence of individual learner differences on written corrective feedback.Based on 200 eighth and ninth grade junior high school students’thinking patterns and tests,60 students were selected as subjects in this study.Based on the comparative analysis and error analysis in second language acquisition as the main theoretical basis,this study analyzed the common types of errors in the use of nonpredicate verbs in junior high school students and their causes.There are three main questions in this study:how about the error frequency of the five forms(present participle,past participle,infinitive,gerund and independent nominative structure)in the nonpredicate verb learning of junior high school students?What kind of mistakes do junior high school students make in the process of learning non-predicate verbs?According to the conclusion of the investigation and research,the author puts forward some suggestions from the aspects of teachers and students in the last part of the article.

RECASTS AS CORRECTIVE FEEDBACK IN CHINA’S ENGLISH CLASSROOM INTERACTION

本文基于30节课堂教学语料调查了中国英语教师使用部分重说反馈语(recast)的频率和规律。数据表明,中国英语教师并不倾向在课堂中频繁使用部分重说;而当他们使用时,他们一般针对学生的语法错误使用部分重说;并且和其它反馈语相比,部分重说不能导致学生产出更多的即时修正。原因可能与部分重说的性质和教师使用它的技巧有关。

The Effects of Written Corrective Feedback on Chinese EFL Learners' Acquisition of English Collocations

The role of written corrective feedback（CF） in the process of acquiring a second language（L2） has been an issue of considerable controversies over past decades. This study thus endeavors to extend current work on written CF by investigating and comparing the effect on collocation learning of one traditional type of feedback—direct corrective feedback（DCF）—with an innovative type of error correction, feedback provided within context—situated feedback（SF）. The effects of the two types of written feedback were measured by examining the accurate use of target collocations in a translation test and a multiple choice test completed by 73 intermediate EFL students in China. Three groups were formed： a DCF group, an SF group, and a control group. The study found that both treatment groups outperformed the control group in the posttests and delayed posttests and that there were significant advantages of the SF group in comparison to the DCF group in both posttests. The results suggested that the provision of written CF was helpful for collocation learning and that situational context could promote the facilitative role of written CF in language acquisition. These findings are discussed from the perspectives of both second language acquisition（SLA） theory and language pedagogy and implications for future research efforts are put forward.

An Investigation into Teachers＇ Corrective Feedback in Chinese EFL Classrooms

This paper reports a study on the provision of teachers＇ corrective feedback （CF） and its effect on learners＇ uptake in Chinese EFL classrooms. It investigated what CF strategies were used and examined the effect of error types on strategy choice as well as the effect of CF strategies on learners＇ response. The subjects were four teachers and 89 English majors from a foreign language school and a top university. Data were collected through 40 class hours of classroom observation and interviews carried out with the four teachers. The CF strategies used were then analyzed both quantitatively and qualitatively. The findings are summarized as follows： 1. In Chinese EFL classrooms, a new type of CF was included, namely, nonverbal signals. With nonverbal signals, teachers could use gestures or facial expressions to indicate the existence of errors in students＇ utterance. Altogether teachers provided seven types of CF in Chinese senior-school and college EFL classrooms： explicit correction, recast, clarification request, metalinguistic feedback, elicitation, repetition and nonverbal signals. All of the seven CF types can be explicit or implicit, input-providing or output-prompting. Implicit/input- providing feedback dominates in the different CF types. 2. Different error types led to different choice of feedback strategies. Discourse errors attracted greatest attention from teachers who showed much more tolerance for syntactic errors than other CF types. Recasts, as implicit/input-providing feedback, were still used most frequently in treating all the error types while teachers tended to prompt students＇ self correction when lexical and discourse errors occurred in order to make error correction salient to learners. 3. Output-prompting feedback worked more effectively in eliciting learners＇ uptake than input- providing strategies did. But input-providing feedback moves yielded a lower needs-repair rate, which means students could do self-correction more successfully when offered with input-providing feedback.The results reveal that different CF strategies can be used according to the nature of errors and thus will yield different responses from learners. Based on these findings, the study suggests that teachers should employ different feedback strategies to improve their teaching qualities.

ALTERNATIVE METHODS OF CORRECTING CHINESE STUDENTS' EFL COLLEGE WRITING

The ability to write in English has become more and more important after China's entrance into the WTO. Unfortunately EFL writing is a headache. Error correction (revision) is still a problem which needs to be solved between English teachers and their students. This paper investigates what Chinese EFL college students think about their teachers feedback in regard to their writing in order to find proper and effective ways to implement error correction by the teacher.

Second Language Research on Recasts:A Critical Review in Response to an Ongoing Debate

This paper reviews important second language research on recasts in response to a recent debate between Goo and Mackey （2013） and Lyster and Ranta （2013） in the journal Studies in Second Language Acquisition. It begins by clarifying the definition of recasts and then examines several controversial issues featuring prominently in the debate, including the theoretical underpinnings of existing research on recasts, mixed findings about their effectiveness in language acquisition, and methodological concerns in effectiveness research. The primary aim of this paper is to demarcate common ground and disagreement that are emerging in this debate and, based on a synthesis and critique of previous empirical studies, to identify directions for future research. It also explores pedagogical implications of recasts research for English-as-a-foreign-language contexts.

The Effects of Recasts and Working Memory on the Development of Implicit and Explicit Knowledge

This paper aims to investigate the effects of recasts and working memory on the acquisition of Korean morphological causatives by advanced Chinese learners of Korean. Participants were randomly assigned to two groups： A experimental group and a control group. The experimental group received intensive recasts during task-based interaction, whereas the control group did not. The effects of recasts were measured by two types of tests： An elicited imitation test, as a measure of implicit knowledge, and an untimed grammaticality judgment test, as a measure of explicit knowledge. The findings are as follows. First, from the pretest to the delayed posttest, recasts facilitated the learners＇ acquisition of causative construction by developing both their implicit and explicit knowledge. Second, the results of delayed posttests showed that recasts were more effective in aiding the development of implicit knowledge than explicit knowledge. Third, working memory was found to be a significant covariate in the facilitative effects of recasts on explicit knowledge; that is, it mediated the development of explicit knowledge via recasts as a significant individual difference factor. The effects of recasts were maintained even when the impact of working memory was controlled. （189 words）