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PAD Class教学模式对英语专业学生写作焦虑影响的实证研究
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作者 王颖 《外国语文》 北大核心 2024年第2期197-206,共10页
本研究以英语专业大一120名学生为实验对象,进行了为期16周的实证研究,以探讨PAD class教学模式对英语专业学生写作焦虑的影响。基于《二语写作焦虑量表》调查问卷结果表明:英语专业学生总体焦虑处于中等焦虑水平,PAD Class能有效降低... 本研究以英语专业大一120名学生为实验对象,进行了为期16周的实证研究,以探讨PAD class教学模式对英语专业学生写作焦虑的影响。基于《二语写作焦虑量表》调查问卷结果表明:英语专业学生总体焦虑处于中等焦虑水平,PAD Class能有效降低学生的写作总体焦虑,其中课堂焦虑、构思焦虑、自信焦虑明显降低,但回避焦虑没有达到显著水平;PAD Class模式对高中低不同写作水平学生的写作焦虑都有影响,对中、低水平学生的写作焦虑缓解比对高水平学生的影响效果更明显。 展开更多
关键词 PAD class 英语专业写作 写作焦虑 实证研究
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Hybrid treatment of varied orthodontic appliances for a patient with skeletal class II and temporomandibular joint disorders:A case report and review of literature
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作者 Tong Lu Li Mei +2 位作者 Bao-Chao Li Zi-Wei Huang Huang Li 《World Journal of Clinical Cases》 SCIE 2024年第2期431-442,共12页
BACKGROUND The relation between orthodontic treatment and temporomandibular disorders(TMDs)is under debate;the management of TMD during orthodontic treatment has always been a challenge.If TMD symptoms occur during or... BACKGROUND The relation between orthodontic treatment and temporomandibular disorders(TMDs)is under debate;the management of TMD during orthodontic treatment has always been a challenge.If TMD symptoms occur during orthodontic treatment,an immediate pause of orthodontic adjustments is recommended;the treatment can resume when the symptoms are managed and stabilized.CASE SUMMARY This case report presents a patient(26-year-old,female)with angle class I,skeletal class II and TMDs.The treatment was a hybrid of clear aligners,fixed appliances and temporary anchorage devices(TADs).After 3 mo resting and treatment on her TMD,the patient’s TMD symptom alleviated,but her anterior occlusion displayed deep overbite.Therefore,the fixed appliances with TAD were used to correct the anterior deep-bite and level maxillary and mandibular deep curves.After the levelling,the patient showed dual bite with centric relation and maximum intercuspation discrepancy on her occlusion.After careful examination of temporomandibular joints(TMJ)position,the stable bite splint and Invisible Mandibular Advancement appliance were used to reconstruct her occlusion.Eventually,the improved facial appearance and relatively stable occlusion were achieved.The 1-year follow-up records showed there was no obvious change in TMJ morphology,and her occlusion was stable.CONCLUSION TMD screening and monitoring is of great clinical importance in the TMD susceptible patients.Hybrid treatment with clear aligners and fixed appliances and TADs is an effective treatment modality for the complex cases. 展开更多
关键词 Temporomandibular disorder Skeletal class II Deep overbite Dual bite Invisible mandibular advancement appliance Case report
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World Class Elite Breaststrokers Downward Kick EMG Muscle Activity of the Gluteus Maximus, Quadriceps Femoris, Hamstring, Gastrocnemius Medialis, Rectus Abdominal, and Erector Spinae
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作者 Takahisa Ide William F.Johnson +10 位作者 Sadafumi Takise Noriko Inada Hiromasa Fujimori Takeharu Fujimori Emi Moronuki Ai Soma Kazuki Watanabe Asahi Nagahata Iryna Glavnyk Mark Nikolaev Bogdan Plavin 《Psychology Research》 2024年第2期64-69,共6页
This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,qua... This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,quadriceps femoris(vastus medialis and rectus femoris),hamstring/long head of the biceps femoris,gastrocnemius medialis,rectus abdominal,and erector spinae when using the downward breaststroke kick technique.We find that when this sample of swimmers utilized the downward breaststroke kick,max speed and velocity per stroke increased,measured by 12,788 EMG samples,where the results are highly correlated to duration of the aerodynamic buoyant force in breaststroke kick technique.The increases in performance observed from measuring the world class elite swimmers is highly correlated to the duration of the kick aerodynamic buoyant force.Among this sample of elite swimmers,the longer a swimmer demonstrates a buoyant force breaststroke kick,the lower the time in a 100 breaststroke. 展开更多
关键词 swimming breaststroke downward kick EMG imagination world class elite swimmers
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基于CLASS促进幼儿教师提升师幼互动能力的策略
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作者 龚方刚 《小学教学研究》 2024年第8期92-93,96,共3页
师幼互动是学前教育课程实施的主要过程,也是学前儿童在幼儿园一日活动中的生活体验、学习体验和情感体验的重要载体。师幼互动的质量对学前教育的质量起决定性作用。CLASS(课堂评价评分系统)不仅可以用来评价课堂师幼互动的质量,还可... 师幼互动是学前教育课程实施的主要过程,也是学前儿童在幼儿园一日活动中的生活体验、学习体验和情感体验的重要载体。师幼互动的质量对学前教育的质量起决定性作用。CLASS(课堂评价评分系统)不仅可以用来评价课堂师幼互动的质量,还可以用于提升教师师幼互动的能力。基于CLASS,文章提出了一系列提升教师师幼互动能力的相关策略。 展开更多
关键词 教师专业发展 幼儿教师 class 师幼互动
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Least Squares One-Class Support Tensor Machine
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作者 Kaiwen Zhao Yali Fan 《Journal of Computer and Communications》 2024年第4期186-200,共15页
One-class classification problem has become a popular problem in many fields, with a wide range of applications in anomaly detection, fault diagnosis, and face recognition. We investigate the one-class classification ... One-class classification problem has become a popular problem in many fields, with a wide range of applications in anomaly detection, fault diagnosis, and face recognition. We investigate the one-class classification problem for second-order tensor data. Traditional vector-based one-class classification methods such as one-class support vector machine (OCSVM) and least squares one-class support vector machine (LSOCSVM) have limitations when tensor is used as input data, so we propose a new tensor one-class classification method, LSOCSTM, which directly uses tensor as input data. On one hand, using tensor as input data not only enables to classify tensor data, but also for vector data, classifying it after high dimensionalizing it into tensor still improves the classification accuracy and overcomes the over-fitting problem. On the other hand, different from one-class support tensor machine (OCSTM), we use squared loss instead of the original loss function so that we solve a series of linear equations instead of quadratic programming problems. Therefore, we use the distance to the hyperplane as a metric for classification, and the proposed method is more accurate and faster compared to existing methods. The experimental results show the high efficiency of the proposed method compared with several state-of-the-art methods. 展开更多
关键词 Least Square One-class Support Tensor Machine One-class classification Upscale Least Square One-class Support Vector Machine One-class Support Tensor Machine
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教师特征对托班师幼互动质量的影响——基于CLASS Toddler的实证研究
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作者 丁骞 郑雯 +1 位作者 张青瑞 吴衍丽 《陕西学前师范学院学报》 2023年第6期78-85,共8页
构建“数量”和“质量”双重保障的托育服务体系是解决“托育难”“幼无所托”等民生难题以及实现人口发展战略重要配套措施。师幼互动是托育服务质量的核心指标,影响婴幼儿身心发展的多个方面。托班师幼互动质量水平不高,尤其不能提供... 构建“数量”和“质量”双重保障的托育服务体系是解决“托育难”“幼无所托”等民生难题以及实现人口发展战略重要配套措施。师幼互动是托育服务质量的核心指标,影响婴幼儿身心发展的多个方面。托班师幼互动质量水平不高,尤其不能提供适宜的学习支持,而教师学历是影响师幼互动质量的重要因素。因此,需要提高托班教师“学历”门槛,建立职前职后“师幼互动”一体化培训体系,重视师幼互动质量的评估,切实提高教师师幼互动能力。 展开更多
关键词 托班 师幼互动 class-T量表
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幼儿园体育活动中师幼互动质量分析及策略研究——基于ClASS课堂互动评估系统的观察分析
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作者 李化树 骆倩 《福建教育》 2023年第47期18-22,共5页
本研究以ClASS课堂互动评估系统为测量工具,对M市6所幼儿园的31个体育集体教学活动视频进行反复观察,以“情感支持”“班级管理”“教育支持”三个维度为切入点,对案例中的师幼互动质量进行评分和分析,揭示当前幼儿园体育活动中师幼互... 本研究以ClASS课堂互动评估系统为测量工具,对M市6所幼儿园的31个体育集体教学活动视频进行反复观察,以“情感支持”“班级管理”“教育支持”三个维度为切入点,对案例中的师幼互动质量进行评分和分析,揭示当前幼儿园体育活动中师幼互动水平。研究结果显示,幼儿园体育活动中师幼互动质量整体上处于中上水平;师幼互动各维度间存在相关性、交融性;不同组织形式的体育活动师幼互动质量存在显著差异。在此基础上,提出相关建议院关注情感支持,构建平等亲密的师幼关系;优化教育行为,营造良好的体育活动生态;重视教育支持,促进幼儿高阶思维发展。 展开更多
关键词 体育活动 师幼互动质量 class课堂互动评估系统
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小学低学段语文优质课堂师生互动特征研究--基于CLASS 课堂评价打分系统的分析
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作者 高振宇 占紫蓉 《北京教育学院学报》 2023年第4期36-47,共12页
采用美国弗吉尼亚大学研究团队开发的课堂评价打分系统(CLASS),围绕情感支持、课堂组织、教学支持三个领域及下设的十个维度,对20节小学低学段语文优质课堂的师生互动状况进行深度观察,探索优质课堂环境下师生互动的整体水平及各维度之... 采用美国弗吉尼亚大学研究团队开发的课堂评价打分系统(CLASS),围绕情感支持、课堂组织、教学支持三个领域及下设的十个维度,对20节小学低学段语文优质课堂的师生互动状况进行深度观察,探索优质课堂环境下师生互动的整体水平及各维度之间的相互关系,并综合量化数据和质性分析得出研究结论。研究发现,小学低学段语文优质课堂在情感支持方面,能较好地激发教师的职业热情,并培养学生自主自立的精神与能力;在课堂组织方面,能以课堂实效为目标,创设高品质的教学活动;在教学支持方面,能营造安全的思维环境,促进师生深度互动。 展开更多
关键词 师生互动 语文优质课 课堂评价打分系统 小学语文
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Infl uence of altitude and tree class on climate-growth relationships in a larch plantation in subtropical China 被引量:1
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作者 Chunyan Wu Dongsheng Chen +1 位作者 Xiaomei Sun Shougong Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1869-1880,共12页
Precise quantifi cation of climate-growth relationships can make a major contribution to scientifi c forest management.However,whether diff erences in the response of growth to climate at diff erent altitudes remains ... Precise quantifi cation of climate-growth relationships can make a major contribution to scientifi c forest management.However,whether diff erences in the response of growth to climate at diff erent altitudes remains unclear.To answer this,264 trees of Larix kaempferi from 88 plots,representing diff erent altitudinal ranges(1000-2100 m)and tree classes were sampled and used to develop tree-ring chronologies.Tree-ring growth(TRG)was either positively(dominant)or negatively(intermediate and suppressed)correlated with climate in diff erent tree classes at diff erent altitudes.TRG was strongly correlated with growing season at low altitudes,but was less sensitive to climate at middle altitudes.It was mainly limited by precipitation and was highly sensitive to climate at low altitudes.Climate-growth relationships at high altitudes were opposite compared to those at low altitudes.TRG of dominant trees was more sensitive to climate change compared to intermediate and suppressed trees.Climate factors(annual temperatures;moisture,the number of frost-free days)had diff erent eff ects on tree-ring growth of diff erent tree classes along altitudinal gradients.It was concluded that the increase in summer temperatures decreased water availability,resulting in a signifi cant decline in growth rates after 2005 at lower altitudes.L.kaempferi is suitable for planting in middle altitudes and dominant trees were the best sampling choice for accurately assessing climate-growth relationships. 展开更多
关键词 Tree-ring width index CHRONOLOGY Correlation coeffi cient Additive mixed models Tree classes
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Visualization for Explanation of Deep Learning-Based Defect Detection Model Using Class Activation Map 被引量:1
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作者 Hyunkyu Shin Yonghan Ahn +3 位作者 Mihwa Song Heungbae Gil Jungsik Choi Sanghyo Lee 《Computers, Materials & Continua》 SCIE EI 2023年第6期4753-4766,共14页
Recently,convolutional neural network(CNN)-based visual inspec-tion has been developed to detect defects on building surfaces automatically.The CNN model demonstrates remarkable accuracy in image data analysis;however... Recently,convolutional neural network(CNN)-based visual inspec-tion has been developed to detect defects on building surfaces automatically.The CNN model demonstrates remarkable accuracy in image data analysis;however,the predicted results have uncertainty in providing accurate informa-tion to users because of the“black box”problem in the deep learning model.Therefore,this study proposes a visual explanation method to overcome the uncertainty limitation of CNN-based defect identification.The visual repre-sentative gradient-weights class activation mapping(Grad-CAM)method is adopted to provide visually explainable information.A visualizing evaluation index is proposed to quantitatively analyze visual representations;this index reflects a rough estimate of the concordance rate between the visualized heat map and intended defects.In addition,an ablation study,adopting three-branch combinations with the VGG16,is implemented to identify perfor-mance variations by visualizing predicted results.Experiments reveal that the proposed model,combined with hybrid pooling,batch normalization,and multi-attention modules,achieves the best performance with an accuracy of 97.77%,corresponding to an improvement of 2.49%compared with the baseline model.Consequently,this study demonstrates that reliable results from an automatic defect classification model can be provided to an inspector through the visual representation of the predicted results using CNN models. 展开更多
关键词 Defect detection VISUALIZATION class activation map deep learning EXPLANATION visualizing evaluation index
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Class Central慕课课程How to Write an Essay教学设计分析
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作者 张春芳 冯建雯 《常州信息职业技术学院学报》 2023年第3期71-73,78,共4页
调研了美国Class Central网站发布的“2023年250门全球最受欢迎在线课程榜”19门英语写作类MOOC课程。How to Write an Essay被列为250门全球最受欢迎MOOC课程之一,源于其优质的教学设计:世界顶尖大学及其丰富的在线课程经验、优秀师资... 调研了美国Class Central网站发布的“2023年250门全球最受欢迎在线课程榜”19门英语写作类MOOC课程。How to Write an Essay被列为250门全球最受欢迎MOOC课程之一,源于其优质的教学设计:世界顶尖大学及其丰富的在线课程经验、优秀师资,教学目标注重培养学习者技能、终身学习理念以及抛锚式教学模式,这对于在线课程建设和教学具有借鉴意义。 展开更多
关键词 class Central MOOC How to Write an Essay 教学设计 抛锚式教学模式
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Combined Effect of Concept Drift and Class Imbalance on Model Performance During Stream Classification
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作者 Abdul Sattar Palli Jafreezal Jaafar +3 位作者 Manzoor Ahmed Hashmani Heitor Murilo Gomes Aeshah Alsughayyir Abdul Rehman Gilal 《Computers, Materials & Continua》 SCIE EI 2023年第4期1827-1845,共19页
Every application in a smart city environment like the smart grid,health monitoring, security, and surveillance generates non-stationary datastreams. Due to such nature, the statistical properties of data changes over... Every application in a smart city environment like the smart grid,health monitoring, security, and surveillance generates non-stationary datastreams. Due to such nature, the statistical properties of data changes overtime, leading to class imbalance and concept drift issues. Both these issuescause model performance degradation. Most of the current work has beenfocused on developing an ensemble strategy by training a new classifier on thelatest data to resolve the issue. These techniques suffer while training the newclassifier if the data is imbalanced. Also, the class imbalance ratio may changegreatly from one input stream to another, making the problem more complex.The existing solutions proposed for addressing the combined issue of classimbalance and concept drift are lacking in understating of correlation of oneproblem with the other. This work studies the association between conceptdrift and class imbalance ratio and then demonstrates how changes in classimbalance ratio along with concept drift affect the classifier’s performance.We analyzed the effect of both the issues on minority and majority classesindividually. To do this, we conducted experiments on benchmark datasetsusing state-of-the-art classifiers especially designed for data stream classification.Precision, recall, F1 score, and geometric mean were used to measure theperformance. Our findings show that when both class imbalance and conceptdrift problems occur together the performance can decrease up to 15%. Ourresults also show that the increase in the imbalance ratio can cause a 10% to15% decrease in the precision scores of both minority and majority classes.The study findings may help in designing intelligent and adaptive solutionsthat can cope with the challenges of non-stationary data streams like conceptdrift and class imbalance. 展开更多
关键词 classIFICATION data streams class imbalance concept drift class imbalance ratio
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Impact of Non-Compliance of Exposure Classes in Reinforced Concrete Structures
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作者 Serigne Touba Thiam Mouhamed Lamine Chérif Aidara Alinté Diatta 《Open Journal of Civil Engineering》 CAS 2023年第1期25-34,共10页
From the National Agency for the Organization and Construction of Infrastructures (ANOCI) program to the Emerging Senegal Plan (PSE), construction in Senegal has improved considerably. However, deficiencies remain in ... From the National Agency for the Organization and Construction of Infrastructures (ANOCI) program to the Emerging Senegal Plan (PSE), construction in Senegal has improved considerably. However, deficiencies remain in the specification of materials used mainly in hydraulic concrete. They are generally related to the specification of aggregates for alkali reactivity and the choice of exposure classes specified in NF EN 206-1. The purpose of this article is to study the incidence of non-compliance with exposure classes in reinforced concrete structures. To carry out this study, surveys were carried out at several sites (districts) in Dakar (Cité Avion, Touba Ouakam, Cité Asecna, Cité Batrain, Cité Comico, Cité Assemblée and Terme Sud) in order to collect information on the formulation and implementation methods used. The comparison of the various readings carried out made it possible to deduce conclusions and to give recommendations when using standard NF EN 206-1. 展开更多
关键词 Common Exposure classes Specific Exposure classes CONCRETE Alkali-Reaction
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Correlation between the Six-Minute Walk Test and Subjective Functional Class in Patients with Heart Failure
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作者 Davi Muzi Rios Gabriela Lira Devens +10 位作者 Leticia Admiral Louzada Priscila Cabral Gomes Coelho Lima Rodolfo Costa Sylvestre Vinicius Angelo Astolpho Lucas Crespo de Barros Larissa Novaes Paganini Lucas Martins Frizzera Borges Renato Giestas Serpa Osmar Araujo Calil Luiz Fernando Machado Barbosa Roberto Ramos Barbosa 《World Journal of Cardiovascular Diseases》 CAS 2023年第4期205-213,共9页
Introduction: The Six-Minute Walk Test (6MWT) is an inexpensive method to objectively evaluate physical capacity or limitation and stratify prognosis in patients with Heart Failure (HF). Since the clinical p... Introduction: The Six-Minute Walk Test (6MWT) is an inexpensive method to objectively evaluate physical capacity or limitation and stratify prognosis in patients with Heart Failure (HF). Since the clinical perception of symptoms may be adapted or compromised, regular evaluation from medical interviews often fails to determine functional classification. This study aimed to assess the correlation between New York Heart Association Functional Class (NYHA-FC) and the distance walked in the 6MWT. Methods: We conducted a cross-sectional observational study that included patients with HF with reduced ejection fraction followed up at an outpatient service of a teaching hospital, from August 2018 to April 2019. Patients in NYHA-FC I, II, or III were included. We compared NYHA-FC subjectively obtained during the consultation with the 6MWT performed after medical consultation, and the correlation between these two parameters was assessed. Results: The study included 70 patients with HF, 41 (58.6%) of whom were female. The mean age was 61.2 ± 12.7 years. The most prevalent etiologies were dilated idiopathic cardiomyopathy (35.7%) followed by ischemic cardiomyopathy (25.7%). The mean ejection fraction was 34.1% ± 9.8%. The average distance walked in the 6MWT by NYHA-FC I patients was 437.8 ± 95.8 meters, NYHA-FC II 360.1 ± 96.4, and NYHA-FC III 248.4 ± 98.3. Functional class measured by the 6MWT was different than that estimated by NYHA-FC in 34 patients (48.6%), 23 (32.9%) for a higher functional class and 11 (15.7%) for a lower one (p = 0.07). Pearson’s correlation coefficient between NYHA-FC and the 6MWT was -0.55. Conclusion: There was a moderate correlation between the subjective NYHA-FC and the 6MWT. The 6MWT revealed a different classification from NYHA-FC in almost half of the patients. Among those who presented discrepancies between methods, 6MWT reclassification towards a higher functional class was more common. 展开更多
关键词 Heart Failure Six-Minute Walk Test Functional class
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ASARA,a prediction model based on Child-Pugh class in hepatocellular carcinoma patients undergoing transarterial chemoembolization
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作者 Ke-Feng Jia Hao Wang +5 位作者 Chang-Lu Yu Wei-Li Yin Xiao-Dong Zhang Fang Wang Cheng Sun Wen Shen 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第5期490-497,共8页
Background:Due to the high heterogeneity among hepatocellular carcinoma(HCC)patients receiving transarterial chemoembolization(TACE),the prognosis of patients varies significantly.The decisionmaking on the initiation ... Background:Due to the high heterogeneity among hepatocellular carcinoma(HCC)patients receiving transarterial chemoembolization(TACE),the prognosis of patients varies significantly.The decisionmaking on the initiation and/or repetition of TACE under different liver functions is a matter of concern in clinical practice.Thus,we aimed to develop a prediction model for TACE candidates using risk stratification based on varied liver function.Methods:A total of 222 unresectable HCC patients who underwent TACE as their only treatment were included in this study.Cox proportional hazards regression was performed to select the independent risk factors and establish a predictive model for the overall survival(OS).The model was validated in patients with different Child-Pugh class and compared to previous TACE scoring systems.Results:The five independent risk factors,including alpha-fetoprotein(AFP)level,maximal tumor size,the increase of albumin-bilirubin(ALBI)grade score,tumor response,and the increase of aspartate aminotransferase(AST),were used to build a prognostic model(ASARA).In the training and validation cohorts,the OS of patients with ASARA score≤2 was significantly higher than that of patients with ASARA score>2(P<0.001,P=0.006,respectively).The ASARA model and its modified version“AS(ARA)”can effectively distinguish the OS(P<0.001,P=0.004)between patients with Child-Pugh class A and B,and the C-index was 0.687 and 0.706,respectively.For repeated TACE,the ASARA model was superior to Assessment for Retreatment with TACE(ART)and ALBI grade,maximal tumor size,AFP,and tumor response(ASAR)among Child-Pugh class A patients.For the first TACE,the performance of AS(ARA)was better than that of modified hepatoma arterial-embolization prognostic(mHAP),mHAP3,and ASA(R)models among Child-Pugh class B patients.Conclusions:The ASARA scoring system is valuable in the decision-making of TACE repetition for HCC patients,especially Child-Pugh class A patients.The modified AS(ARA)can be used to screen the ideal candidate for TACE initiation in Child-Pugh class B patients with poor liver function. 展开更多
关键词 Hepatocellular carcinoma Transarterial chemoembolization Scoring system Prognostic model Child-Pugh class Survival prediction
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A review of addressing class noise problems of remote sensing classification
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作者 FENG Wei LONG Yijun +1 位作者 WANG Shuo QUAN Yinghui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第1期36-46,共11页
The development of image classification is one of the most important research topics in remote sensing. The prediction accuracy depends not only on the appropriate choice of the machine learning method but also on the... The development of image classification is one of the most important research topics in remote sensing. The prediction accuracy depends not only on the appropriate choice of the machine learning method but also on the quality of the training datasets. However, real-world data is not perfect and often suffers from noise. This paper gives an overview of noise filtering methods. Firstly, the types of noise and the consequences of class noise on machine learning are presented. Secondly, class noise handling methods at both the data level and the algorithm level are introduced. Then ensemble-based class noise handling methods including class noise removal, correction, and noise robust ensemble learners are presented. Finally, a summary of existing data-cleaning techniques is given. 展开更多
关键词 class noise label noise mislabeled classification ensemble learning remote sensing
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An Imbalanced Dataset and Class Overlapping Classification Model for Big Data
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作者 Mini Prince P.M.Joe Prathap 《Computer Systems Science & Engineering》 SCIE EI 2023年第2期1009-1024,共16页
Most modern technologies,such as social media,smart cities,and the internet of things(IoT),rely on big data.When big data is used in the real-world applications,two data challenges such as class overlap and class imba... Most modern technologies,such as social media,smart cities,and the internet of things(IoT),rely on big data.When big data is used in the real-world applications,two data challenges such as class overlap and class imbalance arises.When dealing with large datasets,most traditional classifiers are stuck in the local optimum problem.As a result,it’s necessary to look into new methods for dealing with large data collections.Several solutions have been proposed for overcoming this issue.The rapid growth of the available data threatens to limit the usefulness of many traditional methods.Methods such as oversampling and undersampling have shown great promises in addressing the issues of class imbalance.Among all of these techniques,Synthetic Minority Oversampling TechniquE(SMOTE)has produced the best results by generating synthetic samples for the minority class in creating a balanced dataset.The issue is that their practical applicability is restricted to problems involving tens of thousands or lower instances of each.In this paper,we have proposed a parallel mode method using SMOTE and MapReduce strategy,this distributes the operation of the algorithm among a group of computational nodes for addressing the aforementioned problem.Our proposed solution has been divided into three stages.Thefirst stage involves the process of splitting the data into different blocks using a mapping function,followed by a pre-processing step for each mapping block that employs a hybrid SMOTE algo-rithm for solving the class imbalanced problem.On each map block,a decision tree model would be constructed.Finally,the decision tree blocks would be com-bined for creating a classification model.We have used numerous datasets with up to 4 million instances in our experiments for testing the proposed scheme’s cap-abilities.As a result,the Hybrid SMOTE appears to have good scalability within the framework proposed,and it also cuts down the processing time. 展开更多
关键词 Imbalanced dataset class overlapping SMOTE MAPREDUCE parallel programming OVERSAMPLING
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PCATNet: Position-Class Awareness Transformer for Image Captioning
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作者 Ziwei Tang Yaohua Yi +1 位作者 Changhui Yu Aiguo Yin 《Computers, Materials & Continua》 SCIE EI 2023年第6期6007-6022,共16页
Existing image captioning models usually build the relation between visual information and words to generate captions,which lack spatial infor-mation and object classes.To address the issue,we propose a novel Position... Existing image captioning models usually build the relation between visual information and words to generate captions,which lack spatial infor-mation and object classes.To address the issue,we propose a novel Position-Class Awareness Transformer(PCAT)network which can serve as a bridge between the visual features and captions by embedding spatial information and awareness of object classes.In our proposal,we construct our PCAT network by proposing a novel Grid Mapping Position Encoding(GMPE)method and refining the encoder-decoder framework.First,GMPE includes mapping the regions of objects to grids,calculating the relative distance among objects and quantization.Meanwhile,we also improve the Self-attention to adapt the GMPE.Then,we propose a Classes Semantic Quantization strategy to extract semantic information from the object classes,which is employed to facilitate embedding features and refining the encoder-decoder framework.To capture the interaction between multi-modal features,we propose Object Classes Awareness(OCA)to refine the encoder and decoder,namely OCAE and OCAD,respectively.Finally,we apply GMPE,OCAE and OCAD to form various combinations and to complete the entire PCAT.We utilize the MSCOCO dataset to evaluate the performance of our method.The results demonstrate that PCAT outperforms the other competitive methods. 展开更多
关键词 Image captioning relative position encoding object classes awareness
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Improved super-elastic Ti–Ni alloy wire intrusion arch for skeletal class Ⅱ malocclusion combined with deep overbite:A case report
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作者 Ching-Yu Yang Chih-Chieh Lin +2 位作者 I-Jia Wang Yuan-Hou Chen Jian-Hong Yu 《World Journal of Clinical Cases》 SCIE 2023年第17期4142-4151,共10页
BACKGROUND Treatment for deep overbite cases can be difficult. This case report presents some techniques with improved super-elastic Ti–Ni alloy wire(ISW) for deep overbite correction.CASE SUMMARY A 21-year-old woman... BACKGROUND Treatment for deep overbite cases can be difficult. This case report presents some techniques with improved super-elastic Ti–Ni alloy wire(ISW) for deep overbite correction.CASE SUMMARY A 21-year-old woman had a chief complaint of flaring maxillary teeth. Orthodontic evaluation revealed a skeletal class Ⅱ malocclusion and a convex profile appearance. A deep overbite with palatal impingement and large overjet were also noted. Bilateral maxillary first premolars were extracted, and spaces were closed using a closed-coil spring and elastic chain. The deep overbite was corrected by applying the ISW curve and ISW intrusion arch. Intermaxillary elastics was used to adjust the intermaxillary relationship. Active treatment took approximately 3 years, and the appearance and dentition alignment noticeably improved.CONCLUSION The use of the ISW technique in a case of skeletal class Ⅱ malocclusion with deep overbite achieved a desirable result, and the patient was satisfied with the treatment outcome. 展开更多
关键词 Dentistry ORTHODONTICS Skeletal class II Intrusion arch Case report
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Accounting for Heterogeneity in Stop Frequency Models of Work Tours Using Latent Class Poisson Models
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作者 Babak Mirzazadeh 《Journal of Transportation Technologies》 2023年第2期243-261,共19页
Stop frequency models, as one of the elements of activity based models, represent an important part of travel behavior. Unobserved heterogeneity across the travelers should be taken into consideration to prevent biase... Stop frequency models, as one of the elements of activity based models, represent an important part of travel behavior. Unobserved heterogeneity across the travelers should be taken into consideration to prevent biasedness and inconsistency in the estimated parameters in the stop frequency models. Additionally, previous studies on the stop frequency have mostly been done in larger metropolitan areas and less attention has been paid to the areas with less population. This study addresses these gaps by using 2012 travel data from a medium sized U.S. urban area using the work tour for the case study. Stop in the work tour were classified into three groups of outbound leg, work based subtour, and inbound leg of the commutes. Latent Class Poisson Regression Models were used to analyze the data. The results indicate the presence of heterogeneity across the commuters. Using latent class models significantly improves the predictive power of the models compared to regular one class Poisson regression models. In contrast to one class Poisson models, gender becomes insignificant in predicting the number of tours when unobserved heterogeneity is accounted for. The commuters are associated with increased stops on their work based subtour when the employment density of service-related occupations increases in their work zone, but employment density of retail employment does not significantly contribute to the stop making likelihood of the commuters. Additionally, an increase in the number of work tours was associated with fewer stops on the inbound leg of the commute. The results of this study suggest the consideration of unobserved heterogeneity in the stop frequency models and help transportation agencies and policy makers make better inferences from such models. 展开更多
关键词 Activity Based Model Work Tour Stop Frequency Latent class Poisson Regression Model
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