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Significant risk factors for intensive care unit-acquired weakness:A processing strategy based on repeated machine learning 被引量:10
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作者 Ling Wang Deng-Yan Long 《World Journal of Clinical Cases》 SCIE 2024年第7期1235-1242,共8页
BACKGROUND Intensive care unit-acquired weakness(ICU-AW)is a common complication that significantly impacts the patient's recovery process,even leading to adverse outcomes.Currently,there is a lack of effective pr... BACKGROUND Intensive care unit-acquired weakness(ICU-AW)is a common complication that significantly impacts the patient's recovery process,even leading to adverse outcomes.Currently,there is a lack of effective preventive measures.AIM To identify significant risk factors for ICU-AW through iterative machine learning techniques and offer recommendations for its prevention and treatment.METHODS Patients were categorized into ICU-AW and non-ICU-AW groups on the 14th day post-ICU admission.Relevant data from the initial 14 d of ICU stay,such as age,comorbidities,sedative dosage,vasopressor dosage,duration of mechanical ventilation,length of ICU stay,and rehabilitation therapy,were gathered.The relationships between these variables and ICU-AW were examined.Utilizing iterative machine learning techniques,a multilayer perceptron neural network model was developed,and its predictive performance for ICU-AW was assessed using the receiver operating characteristic curve.RESULTS Within the ICU-AW group,age,duration of mechanical ventilation,lorazepam dosage,adrenaline dosage,and length of ICU stay were significantly higher than in the non-ICU-AW group.Additionally,sepsis,multiple organ dysfunction syndrome,hypoalbuminemia,acute heart failure,respiratory failure,acute kidney injury,anemia,stress-related gastrointestinal bleeding,shock,hypertension,coronary artery disease,malignant tumors,and rehabilitation therapy ratios were significantly higher in the ICU-AW group,demonstrating statistical significance.The most influential factors contributing to ICU-AW were identified as the length of ICU stay(100.0%)and the duration of mechanical ventilation(54.9%).The neural network model predicted ICU-AW with an area under the curve of 0.941,sensitivity of 92.2%,and specificity of 82.7%.CONCLUSION The main factors influencing ICU-AW are the length of ICU stay and the duration of mechanical ventilation.A primary preventive strategy,when feasible,involves minimizing both ICU stay and mechanical ventilation duration. 展开更多
关键词 Intensive care unit-acquired weakness Risk factors Machine learning PREVENTION Strategies
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An Incentive Mechanism for Federated Learning:A Continuous Zero-Determinant Strategy Approach
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作者 Changbing Tang Baosen Yang +3 位作者 Xiaodong Xie Guanrong Chen Mohammed A.A.Al-qaness Yang Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期88-102,共15页
As a representative emerging machine learning technique, federated learning(FL) has gained considerable popularity for its special feature of “making data available but not visible”. However, potential problems rema... As a representative emerging machine learning technique, federated learning(FL) has gained considerable popularity for its special feature of “making data available but not visible”. However, potential problems remain, including privacy breaches, imbalances in payment, and inequitable distribution.These shortcomings let devices reluctantly contribute relevant data to, or even refuse to participate in FL. Therefore, in the application of FL, an important but also challenging issue is to motivate as many participants as possible to provide high-quality data to FL. In this paper, we propose an incentive mechanism for FL based on the continuous zero-determinant(CZD) strategies from the perspective of game theory. We first model the interaction between the server and the devices during the FL process as a continuous iterative game. We then apply the CZD strategies for two players and then multiple players to optimize the social welfare of FL, for which we prove that the server can keep social welfare at a high and stable level. Subsequently, we design an incentive mechanism based on the CZD strategies to attract devices to contribute all of their high-accuracy data to FL.Finally, we perform simulations to demonstrate that our proposed CZD-based incentive mechanism can indeed generate high and stable social welfare in FL. 展开更多
关键词 Federated learning(FL) game theory incentive mechanism machine learning zero-determinant strategy
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Reinforcement Learning Based Quantization Strategy Optimal Assignment Algorithm for Mixed Precision
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作者 Yuejiao Wang Zhong Ma +2 位作者 Chaojie Yang Yu Yang Lu Wei 《Computers, Materials & Continua》 SCIE EI 2024年第4期819-836,共18页
The quantization algorithm compresses the original network by reducing the numerical bit width of the model,which improves the computation speed. Because different layers have different redundancy and sensitivity to d... The quantization algorithm compresses the original network by reducing the numerical bit width of the model,which improves the computation speed. Because different layers have different redundancy and sensitivity to databit width. Reducing the data bit width will result in a loss of accuracy. Therefore, it is difficult to determinethe optimal bit width for different parts of the network with guaranteed accuracy. Mixed precision quantizationcan effectively reduce the amount of computation while keeping the model accuracy basically unchanged. In thispaper, a hardware-aware mixed precision quantization strategy optimal assignment algorithm adapted to low bitwidth is proposed, and reinforcement learning is used to automatically predict the mixed precision that meets theconstraints of hardware resources. In the state-space design, the standard deviation of weights is used to measurethe distribution difference of data, the execution speed feedback of simulated neural network accelerator inferenceis used as the environment to limit the action space of the agent, and the accuracy of the quantization model afterretraining is used as the reward function to guide the agent to carry out deep reinforcement learning training. Theexperimental results show that the proposed method obtains a suitable model layer-by-layer quantization strategyunder the condition that the computational resources are satisfied, and themodel accuracy is effectively improved.The proposed method has strong intelligence and certain universality and has strong application potential in thefield of mixed precision quantization and embedded neural network model deployment. 展开更多
关键词 Mixed precision quantization quantization strategy optimal assignment reinforcement learning neural network model deployment
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Dynamic plugging regulating strategy of pipeline robot based on reinforcement learning
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作者 Xing-Yuan Miao Hong Zhao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期597-608,共12页
Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the p... Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process. 展开更多
关键词 Pipeline isolation plugging robot Plugging-induced vibration Dynamic regulating strategy Extreme learning machine Improved sparrow search algorithm Modified Q-learning algorithm
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Enhanced Deep Reinforcement Learning Strategy for Energy Management in Plug-in Hybrid Electric Vehicles with Entropy Regularization and Prioritized Experience Replay
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作者 Li Wang Xiaoyong Wang 《Energy Engineering》 EI 2024年第12期3953-3979,共27页
Plug-in Hybrid Electric Vehicles(PHEVs)represent an innovative breed of transportation,harnessing diverse power sources for enhanced performance.Energy management strategies(EMSs)that coordinate and control different ... Plug-in Hybrid Electric Vehicles(PHEVs)represent an innovative breed of transportation,harnessing diverse power sources for enhanced performance.Energy management strategies(EMSs)that coordinate and control different energy sources is a critical component of PHEV control technology,directly impacting overall vehicle performance.This study proposes an improved deep reinforcement learning(DRL)-based EMSthat optimizes realtime energy allocation and coordinates the operation of multiple power sources.Conventional DRL algorithms struggle to effectively explore all possible state-action combinations within high-dimensional state and action spaces.They often fail to strike an optimal balance between exploration and exploitation,and their assumption of a static environment limits their ability to adapt to changing conditions.Moreover,these algorithms suffer from low sample efficiency.Collectively,these factors contribute to convergence difficulties,low learning efficiency,and instability.To address these challenges,the Deep Deterministic Policy Gradient(DDPG)algorithm is enhanced using entropy regularization and a summation tree-based Prioritized Experience Replay(PER)method,aiming to improve exploration performance and learning efficiency from experience samples.Additionally,the correspondingMarkovDecision Process(MDP)is established.Finally,an EMSbased on the improvedDRLmodel is presented.Comparative simulation experiments are conducted against rule-based,optimization-based,andDRL-based EMSs.The proposed strategy exhibitsminimal deviation fromthe optimal solution obtained by the dynamic programming(DP)strategy that requires global information.In the typical driving scenarios based onWorld Light Vehicle Test Cycle(WLTC)and New European Driving Cycle(NEDC),the proposed method achieved a fuel consumption of 2698.65 g and an Equivalent Fuel Consumption(EFC)of 2696.77 g.Compared to the DP strategy baseline,the proposed method improved the fuel efficiency variances(FEV)by 18.13%,15.1%,and 8.37%over the Deep QNetwork(DQN),Double DRL(DDRL),and original DDPG methods,respectively.The observational outcomes demonstrate that the proposed EMS based on improved DRL framework possesses good real-time performance,stability,and reliability,effectively optimizing vehicle economy and fuel consumption. 展开更多
关键词 Plug-in hybrid electric vehicles deep reinforcement learning energy management strategy deep deterministic policy gradient entropy regularization prioritized experience replay
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The Nature and Use of Technology-Based Self-Regulated Learning Strategies Among EFL Students
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作者 AN Zhujun 《Sino-US English Teaching》 2024年第11期506-514,共9页
This study explored the nature and use of technology-based self-regulated learning(SRL)strategies among the Chinese university students.A total of 20 undergraduate students in China's Mainland were invited to part... This study explored the nature and use of technology-based self-regulated learning(SRL)strategies among the Chinese university students.A total of 20 undergraduate students in China's Mainland were invited to participate in a focus group interview.The students reported using four types of technology-based SRL strategies including cognitive,meta-cognitive,social behavioral,and motivational regulation strategies.Among the strategies,technology-based vocabulary learning was reported to be a dominant strategy by the students.This study opens a new window to understanding how English as a foreign language(EFL)students utilize different strategies to learn English in technology-based learning context. 展开更多
关键词 self-regulated learning technology-based SRL strategies EFL students language learning
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Six-Dimensional Guidance: The Strategies of Thinking Quality Cultivation in Senior High School English Discourse Learning
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作者 Junjie Sun 《Journal of Contemporary Educational Research》 2024年第3期237-245,共9页
Taking the discourse learning of the new senior high school English textbook published by the People’s Education Press as an example,combined with the“six-dimensional guidance”deep reading strategy,and through the ... Taking the discourse learning of the new senior high school English textbook published by the People’s Education Press as an example,combined with the“six-dimensional guidance”deep reading strategy,and through the six-skill training strategies of“memory skill training,understanding skill training,application skill training,analytical skill training,evaluation skill training,creative skill training,”this paper aims to cultivate students’thinking profundity,logic,flexibility,sensitivity,criticality,and originality.It also promotes the real implementation of senior high school English deep reading that points to the cultivation of thinking quality in classroom teaching,and realizes the transformation from“conventional reading”to“deep reading”that reflects the core literacy of the discipline. 展开更多
关键词 Six-dimensional guidance High school English Discourse learning Thinking quality strategy
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Application Strategies of Virtual Reality Technology in the Teaching Design of Vocational Courses from the Perspective of Learning Transfer Theory
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作者 Shuyu Gong 《Journal of Contemporary Educational Research》 2024年第7期1-6,共6页
With the rapid development of virtual reality technology,it has been widely used in the field of education.It can promote the development of learning transfer,which is an effective method for learners to learn effecti... With the rapid development of virtual reality technology,it has been widely used in the field of education.It can promote the development of learning transfer,which is an effective method for learners to learn effectively.Therefore,this paper describes how to use virtual reality technology to achieve learning transfer in order to achieve teaching goals and improve learning efficiency. 展开更多
关键词 learning transfer Virtual reality technology Application strategy
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Developing Learning Strategies: Strategy Instruction
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作者 李佩绮 《海外英语》 2019年第7期249-251,共3页
Learning strategies are critical in the process of learning, knowing, and thinking. Without strategies, nobody can reach competence, to master certain knowledge and skills which makes him/her an independent learner. T... Learning strategies are critical in the process of learning, knowing, and thinking. Without strategies, nobody can reach competence, to master certain knowledge and skills which makes him/her an independent learner. The purose of this paper is trying to demonstrate an overview of leaning strategies based on the researches and studies have been done in the field with emphasis on strategy instruction for increasing reading comprehension and writing instruction. 展开更多
关键词 learning STRATEGIES INSTRUCTION
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Learning Strategies in Chinese EFL Learners' Reading Comprehension 被引量:1
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作者 汪建丽 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2002年第S1期356-358,共3页
According to schema theory resulting from the psycholinguistic model of reading,comprehending a text is an interactive process between the reader background knowledge and the text. This article first views the psychol... According to schema theory resulting from the psycholinguistic model of reading,comprehending a text is an interactive process between the reader background knowledge and the text. This article first views the psycholinguistic model of reading and research in learning strategies, then discusses the application of socioaffective,cognitive, metacognitive learning strategies in Chinese EFL learners’ reading comprehension. 展开更多
关键词 schema theory learning strategy socioaffective COGNITIVE metacognitive
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A Study on Different Learning Strategies Used by EFL Learners in China 被引量:3
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作者 陈明辉 杨蕾达 《海外英语》 2011年第7X期124-125,共2页
This study explores how the Chinese learners apply the learning strategies in the language learning.The research examines how to understand EFL learners uses of learning strategies in language learning.The SILL(the St... This study explores how the Chinese learners apply the learning strategies in the language learning.The research examines how to understand EFL learners uses of learning strategies in language learning.The SILL(the Strategy Inventory for Language Learning) was the instrument of this study.The results show that the frequency of strategy use does not vary among the different levels of learners based on the SILL's mean scores.The results suggest that as the learners' levels become higher,the EFL learners tend to choose more strategies which are reflective of their active learning. 展开更多
关键词 learning strategies ENGLISH teaching SECOND language learning COLLEGE ENGLISH
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Meta-cognitive Strategy Training and the Development of Learners' Autonomy in Language Learning 被引量:3
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作者 王洪林 《Sino-US English Teaching》 2006年第8期20-23,共4页
As the ultimate goal of education, autonomy in language learning has aroused a lot of attention from scholars at home and abroad. While in universities of China, students do not have strong autonomy in English languag... As the ultimate goal of education, autonomy in language learning has aroused a lot of attention from scholars at home and abroad. While in universities of China, students do not have strong autonomy in English language learning. The author tries to adopt specific meta-cognitive strategies to facilitate students' autonomy in learning by improving learners' capacities in study planning or management, monitoring and evaluating in learning to raise their consciousness and ability in autonomy, and lay a foundation for life-long learning. 展开更多
关键词 meta-cognitive strategies meta-cognitive strategies training autonomy in language learning
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Incorporation of Learning Strategies into Web-based Autonomous Listening 被引量:4
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作者 李芳 《海外英语》 2019年第20期278-280,284,共4页
The thesis introduces a comparative study of students'autonomous listening practice in a web-based autonomous learning center and the traditional teacher-dominated listening practice in a traditional language lab.... The thesis introduces a comparative study of students'autonomous listening practice in a web-based autonomous learning center and the traditional teacher-dominated listening practice in a traditional language lab.The purpose of the study is to find how students'listening strategies differ in these two approaches and thereby to find which one better facilitates students'listening proficiency. 展开更多
关键词 learning strategies metacognitive strategies listening strategies WEB-BASED autonomous listening
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An Empirical Study of Depth of Vocabulary Knowledge and Vocabulary Learning Metacognitive Strategies of Non-English Majors 被引量:1
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作者 徐敏娜 骆敏 《海外英语》 2017年第15期11-12,共2页
This paper concentrates on the depth of vocabulary knowledge and vocabulary learning metacognitive strategies used by Chinese non-English majors in an independent college.Results show the depth of vocabulary knowledge... This paper concentrates on the depth of vocabulary knowledge and vocabulary learning metacognitive strategies used by Chinese non-English majors in an independent college.Results show the depth of vocabulary knowledge of the subjects only reaches the passing level.And metacognitive strategies are correlated significantly with the depth of vocabulary knowledge. 展开更多
关键词 vocabulary acquisition depth of vocabulary knowledge vocabulary learning metacognitive strategies CORRELATION
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基于改进Q-Learning的移动机器人路径规划算法
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作者 王立勇 王弘轩 +2 位作者 苏清华 王绅同 张鹏博 《电子测量技术》 北大核心 2024年第9期85-92,共8页
随着移动机器人在生产生活中的深入应用,其路径规划能力也需要向快速性和环境适应性兼备发展。为解决现有移动机器人使用强化学习方法进行路径规划时存在的探索前期容易陷入局部最优、反复搜索同一区域,探索后期收敛率低、收敛速度慢的... 随着移动机器人在生产生活中的深入应用,其路径规划能力也需要向快速性和环境适应性兼备发展。为解决现有移动机器人使用强化学习方法进行路径规划时存在的探索前期容易陷入局部最优、反复搜索同一区域,探索后期收敛率低、收敛速度慢的问题,本研究提出一种改进的Q-Learning算法。该算法改进Q矩阵赋值方法,使迭代前期探索过程具有指向性,并降低碰撞的情况;改进Q矩阵迭代方法,使Q矩阵更新具有前瞻性,避免在一个小区域中反复探索;改进随机探索策略,在迭代前期全面利用环境信息,后期向目标点靠近。在不同栅格地图仿真验证结果表明,本文算法在Q-Learning算法的基础上,通过上述改进降低探索过程中的路径长度、减少抖动并提高收敛的速度,具有更高的计算效率。 展开更多
关键词 路径规划 强化学习 移动机器人 Q-learning算法 ε-decreasing策略
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A Study on English Vocabulary Learning Strategies of College Students 被引量:1
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作者 刘雯 《海外英语》 2010年第7X期259-261,共3页
The present study attempts to investigate Chinese non-English majors' vocabulary learning strategies.The descriptive statistics is carried out on the learners' vocabulary learning strategies;a correlational st... The present study attempts to investigate Chinese non-English majors' vocabulary learning strategies.The descriptive statistics is carried out on the learners' vocabulary learning strategies;a correlational study is conducted between the students' vocabulary learning strategies and their vocabulary test scores.The result shows that students still prefer to learn vocabulary through the traditional way and that the dictionary strategies and rehearsal strategies are negatively related to vocabulary test scores,while all the other five categories are positively related to them.The pedagogical implications of this study are suggested for college teachers' instructions of vocabulary learning strategies. 展开更多
关键词 VOCABULARY learning STRATEGIES VOCABULARY test SCORES QUESTIONNAIRE
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A Synthesis of the Studies on Vocabulary Learning Strategies in ESL and EFL Learning
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作者 陈钧 周超英 《英语广场(学术研究)》 2012年第3期39-42,70,共5页
Vocabulary is the core of language learning.The efficiency of vocabulary learning may influence language learning outcome.Vocabulary learning strategies can help the learners to learn vocabulary more efficiently,and t... Vocabulary is the core of language learning.The efficiency of vocabulary learning may influence language learning outcome.Vocabulary learning strategies can help the learners to learn vocabulary more efficiently,and they are very useful and beneficial for language learners.This paper synthesizes the research on vocabulary learning strategies in ESL and EFL learning,including the studies on the definitions of vocabulary learning strategies,classifications of vocabulary learning strategies and previous main research areas.The previous research areas mainly involve in the following aspects:patterns and taxonomies of vocabulary learning strategies,gender difference and vocabulary learning strategies,language proficiency and vocabulary learning strategies,major or disciplinary difference and vocabulary learning strategies,vocabulary learning strategies used frequently and effectively,vocabulary learning strategies and learning outcomes,and vocabulary learning strategy training. 展开更多
关键词 vocabulary learning strategy DEFINITION classification language proficiency
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Applying the Teaching Strategy of Co-operative Learning to ELT
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作者 谢伟华 《内蒙古师范大学学报(哲学社会科学版)》 1999年第S3期112-114,共3页
This article focuses on a brief introduction of the teaching strategies of Co-operative Learning(CL). Some of the strategies are chosen to make certain changes in ELT field. It is proved that the Teaching Strategy of ... This article focuses on a brief introduction of the teaching strategies of Co-operative Learning(CL). Some of the strategies are chosen to make certain changes in ELT field. It is proved that the Teaching Strategy of CL can be applied in ELT, which makes the classroom teaching more efficient and arose learners’ interests. The Teaching Strategy of CL can help students improve their ability of learning and problem solving. It is a new breakthrough to the traditional teaching model. 展开更多
关键词 co-operative learning the TEACHING strategies GROUP DISCUSSION evaluation
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On Affective Strategies use in College Students' Autonomous English Learning
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作者 黄万武 王珊珊 《海外英语》 2011年第9X期18-18,35,共2页
Autonomous study emphasizes the learner's initiative,enthusiasm and creativity.In all fields of education,there is growing emphasis on "learner-centered" teaching methods and the ability of learner auton... Autonomous study emphasizes the learner's initiative,enthusiasm and creativity.In all fields of education,there is growing emphasis on "learner-centered" teaching methods and the ability of learner autonomy.Many experts and scholars have found that learning strategies plays an important role in English language learning,but the importance of affective strategy use in English learning is often ignored by people.Therefore,this paper focuses on the frequencies of affective strategies use in English learning and their relationships so as to enable college students to use positive affective strategies effectively to improve their autonomous learning ability. 展开更多
关键词 AFFECTIVE strategies AUTONOMOUS ENGLISH learning MOTIVATION
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A Review of Language Learning Strategy
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作者 金俊淑 《教育教学论坛》 2013年第6期122-123,共2页
This paper presents definitions of language learning strategies,discusses four classifications of language learning strategies,focuseson research on language learning strategies,and it aimsto provide areview oflanguag... This paper presents definitions of language learning strategies,discusses four classifications of language learning strategies,focuseson research on language learning strategies,and it aimsto provide areview oflanguage learning strategy. 展开更多
关键词 LANGUAGE learning strategy REVIEW
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