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Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning 被引量:2
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作者 Yun-Peng He Hai-Bo Cheng +4 位作者 Peng Zeng Chuan-Zhi Zang Qing-Wei Dong Guang-Xi Wan Xiao-Ting Dong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期641-653,共13页
High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well operations.Deep learning-based method for classifying the dynamometer card(DC)of oil wells is an eff... High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well operations.Deep learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis method.However,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational effort.Additionally,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different moments.Thus,there is heterogeneity in field data,which can dramatically impair the diagnostic accuracy.To solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this paper.First,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC data.Subsequently,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data heterogeneity.Finally,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the 4S-TFSM.Experiments on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational cost.To the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS. 展开更多
关键词 Sucker-rod pumping system Dynamometer card working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix
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My English Learning
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作者 王冉 张超(指导) 《中学生英语》 2025年第10期7-7,共1页
English is a very important subject at school.I want to learn it well so I work hard.I can remember most new word s.I like pair work best because I like to talk with my classmates in English.I think writing is the mos... English is a very important subject at school.I want to learn it well so I work hard.I can remember most new word s.I like pair work best because I like to talk with my classmates in English.I think writing is the most difficult part in English learning,so I will spend more time on it every day.My writing needs improving.I think reading texts aloud is a very useful way in English learning. 展开更多
关键词 reading texts aloud English learning pair work READING WRITING
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Group Work Learning In English Learning And Teaching 被引量:1
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作者 陈晴霞 《科教文汇》 2007年第11期25-26,32,共3页
Group work learning is one of the hot topics in English learning and teaching today. This discourse will probe the meaning and the advantages of group work learning, as well as its implementation. Also, the discourse ... Group work learning is one of the hot topics in English learning and teaching today. This discourse will probe the meaning and the advantages of group work learning, as well as its implementation. Also, the discourse discusses the proper time for group work learning. In addition to that, problems of group work learning are enclosed. 展开更多
关键词 GROUP work learning TASK TASK-BASED learning
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Few-shot working condition recognition of a sucker-rod pumping system based on a 4-dimensional time-frequency signature and meta-learning convolutional shrinkage neural network 被引量:2
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作者 Yun-Peng He Chuan-Zhi Zang +4 位作者 Peng Zeng Ming-Xin Wang Qing-Wei Dong Guang-Xi Wan Xiao-Ting Dong 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期1142-1154,共13页
The accurate and intelligent identification of the working conditions of a sucker-rod pumping system is necessary. As onshore oil extraction gradually enters its mid-to late-stage, the cost required to train a deep le... The accurate and intelligent identification of the working conditions of a sucker-rod pumping system is necessary. As onshore oil extraction gradually enters its mid-to late-stage, the cost required to train a deep learning working condition recognition model for pumping wells by obtaining enough new working condition samples is expensive. For the few-shot problem and large calculation issues of new working conditions of oil wells, a working condition recognition method for pumping unit wells based on a 4-dimensional time-frequency signature (4D-TFS) and meta-learning convolutional shrinkage neural network (ML-CSNN) is proposed. First, the measured pumping unit well workup data are converted into 4D-TFS data, and the initial feature extraction task is performed while compressing the data. Subsequently, a convolutional shrinkage neural network (CSNN) with a specific structure that can ablate low-frequency features is designed to extract working conditions features. Finally, a meta-learning fine-tuning framework for learning the network parameters that are susceptible to task changes is merged into the CSNN to solve the few-shot issue. The results of the experiments demonstrate that the trained ML-CSNN has good recognition accuracy and generalization ability for few-shot working condition recognition. More specifically, in the case of lower computational complexity, only few-shot samples are needed to fine-tune the network parameters, and the model can be quickly adapted to new classes of well conditions. 展开更多
关键词 Few-shot learning Indicator diagram META-learning Soft thresholding Sucker-rod pumping system Time–frequency signature working condition recognition
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An Intelligent Diagnosis Method of the Working Conditions in Sucker-Rod Pump Wells Based on Convolutional Neural Networks and Transfer Learning 被引量:2
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作者 Ruichao Zhang Liqiang Wang Dechun Chen 《Energy Engineering》 EI 2021年第4期1069-1082,共14页
In recent years,deep learning models represented by convolutional neural networks have shown incomparable advantages in image recognition and have been widely used in various fields.In the diagnosis of sucker-rod pump... In recent years,deep learning models represented by convolutional neural networks have shown incomparable advantages in image recognition and have been widely used in various fields.In the diagnosis of sucker-rod pump working conditions,due to the lack of a large-scale dynamometer card data set,the advantages of a deep convolutional neural network are not well reflected,and its application is limited.Therefore,this paper proposes an intelligent diagnosis method of the working conditions in sucker-rod pump wells based on transfer learning,which is used to solve the problem of too few samples in a dynamometer card data set.Based on the dynamometer cards measured in oilfields,image classification and preprocessing are conducted,and a dynamometer card data set including 10 typical working conditions is created.On this basis,using a trained deep convolutional neural network learning model,model training and parameter optimization are conducted,and the learned deep dynamometer card features are transferred and applied so as to realize the intelligent diagnosis of dynamometer cards.The experimental results show that transfer learning is feasible,and the performance of the deep convolutional neural network is better than that of the shallow convolutional neural network and general fully connected neural network.The deep convolutional neural network can effectively and accurately diagnose the working conditions of sucker-rod pump wells and provide an effective method to solve the problem of few samples in dynamometer card data sets. 展开更多
关键词 Sucker-rod pump well dynamometer card convolutional neural network transfer learning working condition diagnosis
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Teamwork Optimization with Deep Learning Based Fall Detection for IoT-Enabled Smart Healthcare System
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作者 Sarah B.Basahel Saleh Bajaba +2 位作者 Mohammad Yamin Sachi Nandan Mohanty E.Laxmi Lydia 《Computers, Materials & Continua》 SCIE EI 2023年第4期1353-1369,共17页
The current advancement in cloud computing,Artificial Intelligence(AI),and the Internet of Things(IoT)transformed the traditional healthcare system into smart healthcare.Healthcare services could be enhanced by incorp... The current advancement in cloud computing,Artificial Intelligence(AI),and the Internet of Things(IoT)transformed the traditional healthcare system into smart healthcare.Healthcare services could be enhanced by incorporating key techniques like AI and IoT.The convergence of AI and IoT provides distinct opportunities in the medical field.Fall is regarded as a primary cause of death or post-traumatic complication for the ageing population.Therefore,earlier detection of older person falls in smart homes is required to improve the survival rate of an individual or provide the necessary support.Lately,the emergence of IoT,AI,smartphones,wearables,and so on making it possible to design fall detection(FD)systems for smart home care.This article introduces a new Teamwork Optimization with Deep Learning based Fall Detection for IoT Enabled Smart Healthcare Systems(TWODLFDSHS).The TWODL-FDSHS technique’s goal is to detect fall events for a smart healthcare system.Initially,the presented TWODL-FDSHS technique exploits IoT devices for the data collection process.Next,the TWODLFDSHS technique applies the TWO with Capsule Network(CapsNet)model for feature extraction.At last,a deep random vector functional link network(DRVFLN)with an Adam optimizer is exploited for fall event detection.A wide range of simulations took place to exhibit the enhanced performance of the presentedTWODL-FDSHS technique.The experimental outcomes stated the enhancements of the TWODL-FDSHS method over other models with increased accuracy of 98.30%on the URFD dataset. 展开更多
关键词 Internet of things smart healthcare deep learning team work optimizer capsnet fall detection
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基于e-learning平台的“工学结合”教学模式探索 被引量:3
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作者 俞秀金 张耀 吕俊 《实验室研究与探索》 CAS 北大核心 2010年第5期186-187,191,共3页
解决身处异地学生的继续学习问题,是"工学结合"教学模式改革成功的保障。通过e-learning教学平台作用的描述,介绍了e-learning教学平台的构建,阐述了通过e-learning教学平台实施教学。
关键词 “工学结合” E-learning 教学模式
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基于E-Learning的“工学交替”教学及管理模式 被引量:1
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作者 梁颖红 张欣 《苏州市职业大学学报》 2010年第3期77-79,共3页
介绍对开源E-Learning平台进行修改并应用到"工学交替"管理中的方法和实施措施.讨论了采用E-Learning平台对实施"工学交替"学生进行指导、日常管理和综合评价的方案,为职业院校的实践管理提供新的思路.
关键词 电子学习 工学交替 教学模式
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Review on Video Object Tracking Based on Deep Learning 被引量:5
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作者 Fangming Bi Xin Ma +4 位作者 Wei Chen Weidong Fang Huayi Chen Jingru Li Biruk Assefa 《Journal of New Media》 2019年第2期63-74,共12页
Video object tracking is an important research topic of computer vision, whichfinds a wide range of applications in video surveillance, robotics, human-computerinteraction and so on. Although many moving object tracki... Video object tracking is an important research topic of computer vision, whichfinds a wide range of applications in video surveillance, robotics, human-computerinteraction and so on. Although many moving object tracking algorithms have beenproposed, there are still many difficulties in the actual tracking process, such asillumination change, occlusion, motion blurring, scale change, self-change and so on.Therefore, the development of object tracking technology is still challenging. Theemergence of deep learning theory and method provides a new opportunity for theresearch of object tracking, and it is also the main theoretical framework for the researchof moving object tracking algorithm in this paper. In this paper, the existing deeptracking-based target tracking algorithms are classified and sorted out. Based on theprevious knowledge and my own understanding, several solutions are proposed for theexisting methods. In addition, the existing deep learning target tracking method is stilldifficult to meet the requirements of real-time, how to design the network and trackingprocess to achieve speed and effect improvement, there is still a lot of research space. 展开更多
关键词 Object tracking deep learning neural work
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An efficient machine learning-enhanced DTCO framework for low-power and high-performance circuit design
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作者 Mingyang Liu Zhengguang Tang +9 位作者 Hailong You Cong Li Guangxin Guo Zeyuan Wang Linying Zhang Xingming Liu Yu Wang Yong Dai Geng Bai Xiaoling Lin 《Journal of Information and Intelligence》 2025年第3期194-209,共16页
The standard design technology co-optimization(DTCO)involves frequent interactions between circuit design and process manufacturing,which requires several months.To assist designers in establishing a bridge between de... The standard design technology co-optimization(DTCO)involves frequent interactions between circuit design and process manufacturing,which requires several months.To assist designers in establishing a bridge between device parameters and circuit metrics efficiently,and provide guidance for parameter optimization in the early stages of circuit design.In this paper,we propose an efficient machine learning(ML)-enhanced DTCO framework.This framework achieves the co-optimization of device parameters and circuit metrics.We select the gate metal work function(WF)as the parameter to validate the effectiveness of our framework.And the ridge regression approach is used to bypass TCAD simulation,compact model extraction and cell library characterization.We reduces time consumption by at least 92%compared to traditional DTCO framework,while ensuring that errors of delay,internal power consumption and leakage power below 4 ps,0.035mJ,and 0.4μW,respectively.By adjusting the WF,we achieved a better balance between circuit delay and power consumption.This work contributes to designers exploring a broader design space and achieving a efficient DTCO flow. 展开更多
关键词 Machine learning Design technology co-optimization(DTCO) Cell library work function Parameter extraction
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A weighted DJP-MMD based deep transfer metric learning for the fault diagnosis of bearing under variable working conditions
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作者 Zengbing XU Gaige DING +2 位作者 Yaxin NIE Xiaoli SUN Zhigang WANG 《Frontiers of Mechanical Engineering》 2025年第2期89-105,共17页
The change of working conditions not only makes the data distribution inconsistent,but also increases the diagnosis difficulty of fuzzy samples at the fault boundary.The traditional distance-based deep metric learning... The change of working conditions not only makes the data distribution inconsistent,but also increases the diagnosis difficulty of fuzzy samples at the fault boundary.The traditional distance-based deep metric learning cannot effectively classify the fuzzy samples at the fault boundary.In the traditional transfer learning models,the maximum mean discrepancy(MMD)and joint maximum mean discrepancy only increase the transferability of same-class samples,and neglect the discriminability of different-class samples across different domains.The discriminative joint probability MMD(DJP-MMD)increases the transferability of same-class samples and the discriminability of different-class samples across different domains,but it only considers the global transferability of all fault classes,ignoring the different transferability of each same fault class.Therefore,a Yu norm-based deep transfer metric learning based on weighted DJP-MMD is proposed to further improve the diagnosis accuracy of bearings under variable working conditions.The deep transfer metric learning model adopts the Yu norm-based similarity instead of the distance-based similarity to effectively classify the data samples,especially those at the fault boundary,and uses the weighted DJP-MMD to measure the data distribution discrepancy between the source and target domains to increase the transferability of each same-class samples and discriminability of different-class samples across different domains.Through the fault diagnosis analysis on bearings under variable working conditions,the diagnosis results demonstrate that the proposed deep transfer metric learning model can diagnose bearing faults with higher accuracy,stronger generalization and anti-noise capabilities compared with other fault diagnosis methods based on transfer learning. 展开更多
关键词 Yu norm weighted DJP-MMD deep transfer metric learning fault diagnosis variable working conditions
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Translating Interdisciplinary Research on Language Learning into Identifying Specific Learning Disabilities in Verbally Gifted and Average Children and Youth
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作者 Ruby Dawn Lyman Elizabeth Sanders +1 位作者 Robert D. Abbott Virginia W. Berninger 《Journal of Behavioral and Brain Science》 2017年第6期227-246,共20页
The current research was grounded in prior interdisciplinary research that showed cognitive ability (verbal ability for translating cognitions into oral language) and multiple-working memory endophenotypes (behavioral... The current research was grounded in prior interdisciplinary research that showed cognitive ability (verbal ability for translating cognitions into oral language) and multiple-working memory endophenotypes (behavioral markers of genetic or brain bases of language learning) predict reading and writing achievement in students with and without specific learning disabilities in written language (SLDs-WL). Results largely replicated prior findings that verbally gifted with dyslexia score higher on reading and writing achievement than those with average verbal ability but not on endophenotypes. The current study extended that research by comparing those with and without SLDs-WL with assessed verbal ability held constant. The verbally gifted without SLDs-WL (n = 14) scored higher than the verbally gifted with SLDs-WL (n = 27) on six language skills (oral sentence construction, best and fastest handwriting in copying, single real word oral reading accuracy, oral pseudoword reading accuracy and rate) and four endophenotypes (orthographic and morphological coding, orthographic loop, and switching attention). The verbally average without SLDs-WL (n = 6) scored higher than the verbally average with SLDs-WL (n = 22) on four language skills (best and fastest hand-writing in copying, oral pseudoword reading accuracy and rate) and two endophenotypes (orthographic coding and orthographic loop). Implications of results for translating interdisciplinary research into flexible definitions for assessment and instruction to serve students with varying verbal abilities and language learning and endophenotype profiles are discussed along with directions for future research. 展开更多
关键词 Defining SPECIFIC learning DISABILITIES (SLDs) Diagnosing SPECIFIC learning DISABILITIES in Written LANGUAGE (SLDs-WL) Verbal GIFTEDNESS Multi-Component working Memory ENDOPHENOTYPES LANGUAGE learning Mechanism Translation Science for Diagnosis of SLDs
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Child Labor: Prevalence, Reasons and Knowledge of Early Learning of Handicrafts in Couffo, Benin in 2018
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作者 Mênonli Adjobimey Rose Christelle Nayéton Mikponhoue +3 位作者 Paul Yearim Edah Ibrahim Mama Cisse Paul Ayélo Vikkey Antoine Hinson 《Occupational Diseases and Environmental Medicine》 2022年第2期91-101,共11页
Introduction: One form of child labor is early learning, which is a less worrying phenomenon in our communities in Benin. The objective of this study was to assess the practice of early learning for children in rural ... Introduction: One form of child labor is early learning, which is a less worrying phenomenon in our communities in Benin. The objective of this study was to assess the practice of early learning for children in rural areas. Methods: This was a cross-sectional study combined with a qualitative component conducted in the Kissamey district of Benin with four targets: child apprentices (52), master craftsmen (41), parents and guardians (34), local authorities (9). The collection tools were a questionnaire and an interview guide. Results: The frequency of early learning among children was 32.07% with difficult socioeconomic conditions: polygamy (75%), strong siblings (79%), out of school (33%), unmet food needs (96%). The reasons for early learning according to parents were: refusal of the child to go to school (44%), financial difficulties (31%), school failure (22%), but 38% of these children did not know the reason for their learning. The actors had little knowledge of the regulatory texts. Conclusion: Early learning remains a societal problem related to out-of-school and difficult socioeconomic conditions. 展开更多
关键词 work Trades CHILDREN Early learning
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Readdressing The Redundancy Effect: A Cognitive Strategy For E-learning Design
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作者 Sylvie Studente Filia Garivaldis Nina Seppala 《Journal of Psychological Research》 2019年第2期1-7,共7页
This study challenges understandings on the‘redundancy effect’of cognitive load theory and visual/verbal classifications of dual-coding theory.Current understandings assert that a multimedia mix of narration and tex... This study challenges understandings on the‘redundancy effect’of cognitive load theory and visual/verbal classifications of dual-coding theory.Current understandings assert that a multimedia mix of narration and text displayed during e-learning leads to cognitive overload,thus,impeding learning[1,2].Previous research suggests that for optimal learning to occur,the most effective multimedia mix for e-learning presentation is the use of graphics and narration[3-6].The current study was undertaken with 90 undergraduate students at a British University.Participants were allocated to one of three groups.Each group used a different multimedia mix of a music e-learning program.Participants received learning material electronically,which involved either a mix of narration and text,graphics and text,or graphics and narration.Learning was measured by differences in music knowledge scores obtained before and after receiving the learning material.Results indicate that the combination of text and narration is most effective for learning,compared to combinations of graphics and text and graphics and narration.These findings challenge the currently accepted stance on the redundancy effect in e-learning design. 展开更多
关键词 learning MEMORY working MEMORY GRAPHICAL USER INTERFACES
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On Collaborative Learning in English Classes
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作者 庞炜 《海外英语》 2019年第1期251-252,共2页
The current situation of English learners in class is not optimistic. Facing with such a situation, how to promote students' learning is a big problem in English teaching. Cooperative learning is a kind of effecti... The current situation of English learners in class is not optimistic. Facing with such a situation, how to promote students' learning is a big problem in English teaching. Cooperative learning is a kind of effective learning method and teaching strategy,which is student-centered, group-centered, and aims at common learning goals. The paper focuses on the definition, advantages and effective implementation of cooperative learning. 展开更多
关键词 ENGLISH CLASSES COLLABORATIVE learning GROUP work
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Discussion on the Rational Application of Cooperative Learning Theory in College English Reading Teaching
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作者 WU Jiawen 《外文科技期刊数据库(文摘版)教育科学》 2021年第7期111-113,共5页
Since entering the 19th century, cooperative learning theory has been gradually formed and popularized. It has played a very important role in the field of education and has become the most important way of learning i... Since entering the 19th century, cooperative learning theory has been gradually formed and popularized. It has played a very important role in the field of education and has become the most important way of learning in the field of education. In the process of college English teaching, reading teaching, as an important component, enables students to learn English knowledge better through reading, thus improving students' reading comprehension and arousing students to think and analyze deeply. However, in the process of college English reading teaching, there are still many problems, especially the students' poor English reading ability and the inefficient classroom teaching, which seriously hinder the healthy development of college English reading teaching. Therefore, the cooperative learning theory is integrated into the teaching process, and the teaching model and methods of college English reading are continuously innovated, thus effectively improving the efficiency and quality of college English reading teaching. 展开更多
关键词 cooperative learning college English reading teaching group work
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“个性化指导”的一个工作框架:基于数学教学的分析 被引量:1
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作者 马文杰 姜涛 李三平 《数学教育学报》 北大核心 2025年第3期97-102,共6页
个性化指导,既是补充数学课堂集体教学的基本方式,也是满足学生个性化数学学习需求的重要手段.《义务教育数学课程标准(2022年版)》明确提出了“个性化指导”及其相应要求.在已有相关研究基础上,结合对学生在数学学习中进行个性化指导... 个性化指导,既是补充数学课堂集体教学的基本方式,也是满足学生个性化数学学习需求的重要手段.《义务教育数学课程标准(2022年版)》明确提出了“个性化指导”及其相应要求.在已有相关研究基础上,结合对学生在数学学习中进行个性化指导的经验,基于数学教育教学构建了个性化指导的工作框架.即分析个性化指导的基本内涵、基本意义与8个基本特征,在此基础上进一步分析个性化指导的4个基本环节与主要内容,以及进行个性化指导的过程中应该注意的6个方面问题等. 展开更多
关键词 数学学习 个性化指导 工作框架 个性化需求 个别化教学
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基于半监督学习的抽油机井故障诊断方法研究
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作者 何岩峰 王相 +2 位作者 褚宪翔 邵志伟 李明 《钻采工艺》 北大核心 2025年第1期228-237,共10页
近年来,基于深度学习的油井故障诊断方法取得了显著进展,但这类方法的性能高度依赖标注样本集的数量和质量,且深度学习模型经过训练后可诊断的故障类型被固定,增加新类型需要重新收集样本并进行再训练,灵活性不足。为解决上述问题,文章... 近年来,基于深度学习的油井故障诊断方法取得了显著进展,但这类方法的性能高度依赖标注样本集的数量和质量,且深度学习模型经过训练后可诊断的故障类型被固定,增加新类型需要重新收集样本并进行再训练,灵活性不足。为解决上述问题,文章提出了一种基于半监督学习的抽油机井故障诊断方法。该方法利用VGG19与小批量K均值相结合对大量示功图进行自动聚类分析,通过对聚类结果实施批量标注,能够有效提升样本分类的科学性及标注效率。在此基础上,构建基于欧氏距离的K近邻算法实现故障诊断,避免了深度学习方法中繁琐的模型训练及参数调优过程,同时支持样本集动态更新。基于矿场实际数据的实验结果显示,所提出的半监督学习诊断方法可达到与深度学习方法相当的准确率(均超过90%),但在前期准备阶段所需的时间成本减少了90%以上。更重要的是,当面对新出现的故障类型时,本方法能够快速响应并适应,极大地增强了抽油机井故障诊断系统的灵活性。 展开更多
关键词 抽油机井 故障诊断 示功图 机器学习 半监督学习
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