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Professional Development of Rural PE Teachers from the Perspective of PCK:A Case Study of Huaiji County
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作者 Lina MA Manhua HE 《Meteorological and Environmental Research》 2024年第1期57-61,66,共6页
Based on the four dimensions of PCK,this paper investigates the professional development of rural PE teachers in Huaiji County by using the research methods of literature,questionnaire,interview and mathematical stati... Based on the four dimensions of PCK,this paper investigates the professional development of rural PE teachers in Huaiji County by using the research methods of literature,questionnaire,interview and mathematical statistics.Based on PCK related theories,this paper analyzes the current situation of professional development of rural PE teachers in Huaiji County,explores the problems existing in the process of professional development,and provides an optimal path for the professional development of rural PE teachers,so as to improve the teaching ability and classroom quality of rural PE teachers,and promote the further development of rural PE education under the background of new curriculum reform.Through the research,it is found that the shortcomings of rural PE teachers are:lack of situational knowledge;lack of understanding of the course content;not flexible use of teaching representation;low ability to identify the differences of students learning styles;lack of understanding of social environment,etc. 展开更多
关键词 PCK Rural pe teacher Professional development
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The Emergence of Loving Pedagogy in the L2 Affective Domain:How Affective Pedagogy Accounts for Chinese EFL Teachers’Professional Success and Job Satisfaction?
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作者 Yi Li Xinpeng Wang 《International Journal of Mental Health Promotion》 2024年第3期239-250,共12页
The success of teachers in professional environments has a desirable influence on their mental condition.Simply said,teachers’professional success plays a crucial role in improving their mental health.Due to the inva... The success of teachers in professional environments has a desirable influence on their mental condition.Simply said,teachers’professional success plays a crucial role in improving their mental health.Due to the invaluable role of professional success in teachers’mental health,personal and professional variables helping teachers succeed in their profession need to be uncovered.While the role of teachers’personal qualities has been well researched,the function of professional variables has remained unknown.To address the existing gap,the current investigation measured the role of two professional variables,namely job satisfaction and loving pedagogy,in Chinese EFL teachers’professional success.To do this,three validated scales were provided to 1591 Chinese EFL teachers.Participants’answers to the questionnaires were analyzed using the Spearman correlation test and structural equation modeling.The data analysis demonstrated a strong,positive link between the variables.Moreover,loving pedagogy was found to be the positive,strong predictor of Chinese EFL teachers’job satisfaction and professional success.The findings of the current inquiry may help educational administrators enhance their instructors’professional success,which in turn promotes their mental and psychological conditions at work. 展开更多
关键词 Professional success mental health psychological condition loving pedagogy job satisfaction EFL teachers
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Teachers’Perception for Evaluation of the Primary School Students With Final Grade
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作者 Bashkim Rakaj 《Management Studies》 2024年第1期42-57,共16页
The most difficult and delicate part of the learning process is assessment.Assessment is difficult because during his/her accomplishment the teacher has to consider not only the acquisition of knowledge from students,... The most difficult and delicate part of the learning process is assessment.Assessment is difficult because during his/her accomplishment the teacher has to consider not only the acquisition of knowledge from students,but also the overall degree of development of their competencies.It is delicate,because through assessment we can influence the emotional side of students and their“willingness”to learn.Despite these facts,teachers need to evaluate students during the learning process.The purpose of the research is to find out what is the perception of teachers about the level of evaluation of students with final grade.The overall results showed that 89%of teachers agree,9%of them have a neutral attitude,and 2%do not agree that the evaluation of students with a final grade is done taking into account many aspects and using many methods,the overall average of the results,M=4.36.Based on the empirical results,it was found that teachers who have completed assessment training have a more positive approach to student assessment,as the average score is higher than teachers who have not completed assessment training.From the qualitative results it was understood that the Teachers did not encounter any difficulties during the assessment of the students. 展开更多
关键词 TEACHER STUDENT final grade perception EVALUATION
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Research on the Lifting Path of Data Literacy Ability of Applied University Teachers under the Perspective of Organizational Learning
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作者 Shuli Gao Yanli Guo 《Open Journal of Applied Sciences》 2024年第2期320-329,共10页
With the arrival of the big data era, the modern higher education model has undergone radical changes, and higher requirements have been put forward for the data literacy of college teachers. The paper first analyzes ... With the arrival of the big data era, the modern higher education model has undergone radical changes, and higher requirements have been put forward for the data literacy of college teachers. The paper first analyzes the connotation of teacher data literacy, and then combs through the status quo and dilemmas of teachers’ data literacy ability in applied universities. The paper proposes to enhance the data literacy ability of teachers from the perspective of organizational learning. Through building a digital culture, building a data-driven teaching environment, and constructing an interdisciplinary learning community to further promote the application of the theory and practice of datafication inside and outside the organization, and ultimately improve the quality of teaching. 展开更多
关键词 Organizational Learning teachers Data Literacy Lifting Paths
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The Appeals,Dilemmas,and Pathways of Enabling Rural Teachers’Professional Development Through Emerging Technologies
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作者 Hailang Chen Jianhua Huang 《Journal of Contemporary Educational Research》 2024年第5期240-246,共7页
With the rapid advancements in technology,especially in digitalization and intelligence,numerous modern technologies have poured into rural schools,effectively improving their informatization conditions.Nevertheless,t... With the rapid advancements in technology,especially in digitalization and intelligence,numerous modern technologies have poured into rural schools,effectively improving their informatization conditions.Nevertheless,these technologies remain detached from rural teachers,failing to significantly enhance the quality of education and teaching in rural areas.Rural education is a crucial aspect of ensuring balanced development in education.The question of how to enhance rural teachers’technological application abilities and fully leverage the positive role of technology in rural education and teaching has become a significant topic of current research on rural education issues.To better address this question,this study conducted a thorough examination of the specific appeals of rural teachers in the process of technology enablement.It was discovered that rural teachers generally face dilemmas such as insufficient technological application abilities,difficulties in obtaining quality teaching resources,and the lack of continuous technical support and update mechanisms.Based on these findings,specific pathways such as strengthening rural teacher training,optimizing the allocation of educational resources,and establishing mechanisms for continuous technical support and updates are proposed to aid in the high-quality development of rural education. 展开更多
关键词 Teacher professional development Emerging technologies Lifelong learning
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Research on the Role of Guiding Students to Participate in Skills Competitions on the Development of Young Teachers in Vocational Colleges
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作者 Jinru Ma Meiqin Liang 《Journal of Contemporary Educational Research》 2024年第5期212-217,共6页
This paper explores the role of guiding students to participate in skills competitions on the development of young teachers in vocational colleges.We investigate the impact of skills competitions on the consolidation ... This paper explores the role of guiding students to participate in skills competitions on the development of young teachers in vocational colleges.We investigate the impact of skills competitions on the consolidation of professional knowledge,development of innovation capabilities,improvement of hands-on abilities,and enhancement of communication skills with students.The results of this research demonstrate that skills competitions have a positive influence on the professional growth of young teachers.The consolidation of professional knowledge,development of innovation capabilities,improvement of hands-on abilities,and enhancement of communication skills collectively contribute to the effectiveness of young teachers in vocational colleges.It is recommended that vocational colleges prioritize and support the participation of young teachers in skills competitions to foster their professional development. 展开更多
关键词 Skills competitions Young teachers Vocational colleges Professional development Communication skills
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Reading Loss in Arabic Language During COVID-19 in the UAE and Proposed Solutions:The Perspectives of Primary-Grade Arabic Language Teachers
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作者 Karima Almazroui Muhra Albloushi 《Journal of Sociology Study》 2024年第2期107-118,共12页
The COVID-19 pandemic caused significant disruptions in the field of education worldwide,including in the United Arab Emirates.Teachers and students had to adapt to remote learning and virtual classrooms,leading to va... The COVID-19 pandemic caused significant disruptions in the field of education worldwide,including in the United Arab Emirates.Teachers and students had to adapt to remote learning and virtual classrooms,leading to various challenges in maintaining educational standards.The sudden transition to remote teaching could have a negative impact on students’reading abilities,especially in the Arabic language.To gain insight into the unique challenges encountered by Arabic language teachers in the UAE,a survey was conducted to explore their assessment of teaching quality,student-teacher interaction,and learning outcomes amidst the COVID-19 pandemic.The results of the survey revealed a significant decline of student reading abilities and identified several major issues in online Arabic language teaching.These issues included limited interaction between students and teachers,challenges in monitoring students’class participation and performance,and challenges in effectively assessing students’reading skills.The results also demonstrated some other challenges faced by Arabic language teachers,including a lack of preparedness,a lack of subscription to relevant platforms,and a lack of resources for online learning.Several solutions to these challenges are proposed,including reevaluating the balance between depth and breadth in the curriculum,integrating language skills into the curriculum more effectively,providing more comprehensive teacher professional development,implementing student grouping strategies,utilizing retired and expert teachers in specific content areas,allocating time for interventions,and improving support from both teachers and parents to ensure the quality of online learning. 展开更多
关键词 reading loss Arabic language teachers primary grades online learning United Arab Emirates
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Research on the Status Quo and Improvement Needs of Foreign Language Teachers’ Teaching Competence in Curriculum-Based Ideological Education in Xinjiang Colleges and Universities
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作者 Xiaoling Liu 《Journal of Contemporary Educational Research》 2024年第3期101-110,共10页
This study investigated the status quo and further improvement needs of foreign language teachers’teaching competence in curriculum-based ideological education(CIE)in Xinjiang colleges and universities.The results sh... This study investigated the status quo and further improvement needs of foreign language teachers’teaching competence in curriculum-based ideological education(CIE)in Xinjiang colleges and universities.The results show that the teachers’teaching competence in CIE is generally good,with the“cultivating quality”being the highest and the“scientific research quality”the lowest;there still exist several problems,such as teachers’lack of theoretical knowledge in CIE,lack of teaching resources,and insufficient abilities in teaching design and research.It is hoped that with the support and efforts from university administrations,teachers can improve their teaching competence in CIE through various approaches adopted and multiple measures taken,thus optimizing their teaching effectiveness,promoting the construction of CIE in Xinjiang colleges and universities in the new era,and contributing to Xinjiang’s high-quality development. 展开更多
关键词 Foreign language teachers Curriculum-based ideological education Teaching competence Status quo Improvement needs
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PE纤维与细橡胶颗粒对泡沫混凝土弯曲韧性的影响
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作者 吴昊 龙广成 +2 位作者 杨恺 曾晓辉 唐卓 《建筑材料学报》 EI CAS CSCD 北大核心 2024年第3期206-214,共9页
研究了聚乙烯(PE)纤维及其与细橡胶颗粒复掺对泡沫混凝土弯曲破坏模式、峰值强度、能量吸收特性和弯曲韧性的影响,并结合孔结构分析和微观形貌观察探究了其作用机理.结果表明:PE纤维使泡沫混凝土出现多缝开裂模式,显著提升了其峰值强度... 研究了聚乙烯(PE)纤维及其与细橡胶颗粒复掺对泡沫混凝土弯曲破坏模式、峰值强度、能量吸收特性和弯曲韧性的影响,并结合孔结构分析和微观形貌观察探究了其作用机理.结果表明:PE纤维使泡沫混凝土出现多缝开裂模式,显著提升了其峰值强度、能量吸收能力和弯曲韧性;复掺细橡胶颗粒可以进一步提升泡沫混凝土试件的比能量吸收和弯曲韧性;掺入PE纤维可以降低泡沫混凝土的平均孔径;复掺细橡胶颗粒导致泡沫混凝土试件的平均孔径增大,联通孔增多,对其峰值强度有不利影响;PE纤维及细橡胶颗粒提升泡沫混凝土弯曲韧性的主要原因在于其削弱了裂纹尖端的应力集中,同时增强了能量耗散作用. 展开更多
关键词 泡沫混凝土 pe纤维 细橡胶颗粒 弯曲韧性 机理
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PE管道的爆破振动响应规律及灰色关联度分析
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作者 段宝福 于昭文 +2 位作者 徐伟善 孙宗军 张正欣 《工程爆破》 CSCD 北大核心 2024年第1期110-118,共9页
为了降低隧道爆破施工对既有埋地PE管道造成的振动危害,有必要在施工前了解影响管道振动效应的各种因素。根据现场实测数据,采用MIDAS GTS NX软件建立岩土体-隧道-PE管道三维数值模型,并将现场监测结果和数值模拟结果进行对比分析,验证... 为了降低隧道爆破施工对既有埋地PE管道造成的振动危害,有必要在施工前了解影响管道振动效应的各种因素。根据现场实测数据,采用MIDAS GTS NX软件建立岩土体-隧道-PE管道三维数值模型,并将现场监测结果和数值模拟结果进行对比分析,验证数值模型的可靠性。分析得出:爆破振动作用下土体弹性模量、泊松比和管径的增加会使管道的最大振速增大;因为地表自由面叠加作用的原因,管道埋深的增加使管道最大振速先减小后增大。运用灰色关联度理论,确定了4种不同因素对管道振动效应的影响程度,主次关系为:土体弹性模量>管道埋深>土体泊松比>管道直径。准确地了解各因素对管道振动的影响程度能够更好的对隧道爆破施工时PE管道的安全性进行评估,为工程实际施工提供参考。 展开更多
关键词 隧道爆破 灰色关联度 pe管道 振动响应
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CFRP-PE-不锈钢筋混凝土短柱的设计方法研究
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作者 王志滨 宋培 +2 位作者 徐辉 邱瑞明 张健斌 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第5期22-33,共12页
进行了17个CFRP-PE-不锈钢筋混凝土短柱和8个对比试件的轴压试验,探究不锈钢种类、箍筋间距、CFRP厚度、PE厚度对该类组合柱的破坏模态、荷载-应变曲线、极限应变、极限承载力、延性的影响规律.试验结果表明:在CFRP和混凝土间设置PE垫... 进行了17个CFRP-PE-不锈钢筋混凝土短柱和8个对比试件的轴压试验,探究不锈钢种类、箍筋间距、CFRP厚度、PE厚度对该类组合柱的破坏模态、荷载-应变曲线、极限应变、极限承载力、延性的影响规律.试验结果表明:在CFRP和混凝土间设置PE垫层能提高该类组合短柱的延性和变形能力,并降低其承载力;增大CFRP厚度可提高其承载力和极限应变,但试件表现出增大的脆性;减小箍筋间距或增大钢筋强度可显著提高其承载力、峰值应变和延性.建立了有限元模型,有限元分析表明:增大PE厚径比会显著提高该类组合短柱的变形能力和延性,并降低CFRP对其承载力的影响;增大配箍率、不锈钢强度、CFRP抗拉强度、CFRP厚度可提升该类组合短柱的极限应变与承载力;提高混凝土强度会提高该类组合短柱的峰值承载力,但降低其极限应变.最终建议了该类组合短柱的延性设计方法、承载力模型和极限应变模型. 展开更多
关键词 CFRP-pe-不锈钢筋混凝土 pe垫层 延性设计 承载力模型 有限元模型
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生物油/预处理废旧PE复合改性沥青研究
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作者 冯新军 傅豪 《建筑材料学报》 EI CAS CSCD 北大核心 2024年第1期37-45,75,共10页
为了解决废旧塑料改性沥青储存稳定性和低温抗裂性差等问题,采用双螺杆挤出机对废旧聚乙烯(PE)进行预处理,并将其与生物油复合制得生物油/预处理废旧PE复合改性沥青.采用离析试验、流变性能试验、荧光显微镜试验和傅里叶变换红外光谱试... 为了解决废旧塑料改性沥青储存稳定性和低温抗裂性差等问题,采用双螺杆挤出机对废旧聚乙烯(PE)进行预处理,并将其与生物油复合制得生物油/预处理废旧PE复合改性沥青.采用离析试验、流变性能试验、荧光显微镜试验和傅里叶变换红外光谱试验分析了改性沥青的储存稳定性、低温抗裂性和高温稳定性.结果表明:经预处理后的PE密度与沥青密度相近,极性基团和C=C结构更多,化学活性增强,大大提高了废旧PE改性沥青的储存稳定性;生物油/预处理废旧PE复合改性沥青形成了连续的网状结构,进一步提高了废旧PE改性沥青的储存稳定性,并显著提升了其低温抗裂性,但降低了其高温稳定性. 展开更多
关键词 改性沥青 生物油 预处理废旧pe 储存稳定性 低温抗裂性
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非洲猪瘟病毒pE120R蛋白单克隆抗体的制备
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作者 刘传霞 王晓 +5 位作者 李雪雯 鲍苗菲 李婷婷 陈欣 翁长江 郑君 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第1期388-394,共7页
本研究旨在表达非洲猪瘟病毒(ASFV)衣壳蛋白pE120R,并制备单克隆抗体,为其功能研究提供材料。以pCAGGS-Flag-pE120R为模板扩增pE120R基因片段,构建原核表达质粒pGEX-6p1-pE120R。将其转化BL21(DE3)感受态细胞后经IPTG诱导表达为可溶性pE... 本研究旨在表达非洲猪瘟病毒(ASFV)衣壳蛋白pE120R,并制备单克隆抗体,为其功能研究提供材料。以pCAGGS-Flag-pE120R为模板扩增pE120R基因片段,构建原核表达质粒pGEX-6p1-pE120R。将其转化BL21(DE3)感受态细胞后经IPTG诱导表达为可溶性pE120R蛋白,采用GST Beads纯化pE120R蛋白,免疫BALB/c小鼠,然后取其脾细胞与SP2/0细胞进行细胞融合,采用间接ELISA方法筛选获得了1株能够稳定分泌pE120R单克隆抗体的杂交瘤细胞株。结果表明,成功构建了原核表达质粒pGEX-6p1-pE120R,并获得较高纯度的pE120R蛋白。Western blot和间接免疫荧光(IFA)试验结果显示,pE120R单抗能特异性识别HEK293T细胞转染质粒表达的Flag-pE120R蛋白和肺泡巨噬细胞(PAMs)感染ASFV后表达的pE120R蛋白。该单抗的结合位点在30~60aa区域,并且该单抗亚类鉴定重链为IgG2a。本研究成功表达并纯化了可溶性的pE120R蛋白;制备了抗pE120R的单抗隆抗体,该抗体具有良好的特异性,为深入探讨ASFV pE120R蛋白的生物学功能奠定了基础。 展开更多
关键词 非洲猪瘟病毒 pe120R蛋白 原核表达 单抗隆抗体
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非洲猪瘟病毒pE248R蛋白的原核表达及其多克隆抗体制备
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作者 杜楠楠 陈金霞 +6 位作者 曹云雷 张宽 童武 李丽薇 赵冉 童光志 高飞 《中国动物传染病学报》 CAS 北大核心 2024年第2期188-194,共7页
本研究利用PCR方法从非洲猪瘟病毒的灭活样品中扩增出747 bp的E248R基因全长序列,利用同源重组法构建原核表达质粒pCold I-pE248R,经1 mmol/L的IPTG诱导1 h后,利用SDS-PAGE对重组蛋白进行表达鉴定和反应原性分析,表达蛋白的分子量约为32... 本研究利用PCR方法从非洲猪瘟病毒的灭活样品中扩增出747 bp的E248R基因全长序列,利用同源重组法构建原核表达质粒pCold I-pE248R,经1 mmol/L的IPTG诱导1 h后,利用SDS-PAGE对重组蛋白进行表达鉴定和反应原性分析,表达蛋白的分子量约为32 kDa,利用纯化后得到pE248R重组蛋白作为免疫原经过4次免疫后制备鼠源抗pE248R多克隆抗体。利用该多克隆抗体检测实验室构建并拯救的已证明能够稳定表达ASFV pE248R蛋白的重组病毒rPRRSV-E248R,结果显示制备的抗pE248R的多克隆抗体能够与rPRRSV-E248R发生特异性结合反应,证明利用本试验中原核表达的pE248R蛋白制备的多克隆抗体具有抗pE248R蛋白的特异性,为进一步针对ASFV E248R基因建立快速,特异性的血清学检测方法奠定了基础,也为针对pE248R蛋白的功能性研究提供了研究基础。 展开更多
关键词 非洲猪瘟病毒 E248R基因 pe248R蛋白 多克隆抗体
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沙漠砂PE纤维ECC的拉伸性能与本构模型研究
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作者 郑志超 韩风霞 刘继颜 《新疆大学学报(自然科学版)(中英文)》 CAS 2024年第1期121-128,共8页
采用中国新疆本地原材料沙漠砂替代部分天然砂,以聚乙烯(Polyethylene,PE)纤维掺量及水胶比为变量,进行超高韧性水泥基复合材料(Engineered Cementitious Composite,ECC)的单轴拉伸试验,分析不同材料组分对沙漠砂聚乙烯纤维超高韧性水... 采用中国新疆本地原材料沙漠砂替代部分天然砂,以聚乙烯(Polyethylene,PE)纤维掺量及水胶比为变量,进行超高韧性水泥基复合材料(Engineered Cementitious Composite,ECC)的单轴拉伸试验,分析不同材料组分对沙漠砂聚乙烯纤维超高韧性水泥基复合材料试件单轴拉伸性能的影响规律.通过对其单轴拉伸应力-应变关系的分析,考虑纤维掺量、水胶比参数变化,采用最小二乘法对其本构进行回归分析,在试件的强化阶段使用非线性曲线表示,建立沙漠砂聚乙烯纤维超高韧性水泥基复合材料的拉伸本构模型.结果表明:所建拉伸本构模型可以较好地预测PE-ECC的拉伸应力-应变关系,与试验结果吻合较好. 展开更多
关键词 pe纤维 沙漠砂 拉伸性能 本构模型 应力-应变曲线
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基于VMD-PE-MulitiBiLSTM的超短期风电功率预测
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作者 陈烨烨 李瑶 李捍东 《分布式能源》 2024年第2期1-7,共7页
为减少超短期风电功率预测的误差,提出基于变分模态分解(variational mode decomposition,VMD)-排列熵(permutation entropy,PE)和多层双向长短时记忆(multilayer bidirectional long short-term memory,MultiBiLSTM)组合的超短期风电... 为减少超短期风电功率预测的误差,提出基于变分模态分解(variational mode decomposition,VMD)-排列熵(permutation entropy,PE)和多层双向长短时记忆(multilayer bidirectional long short-term memory,MultiBiLSTM)组合的超短期风电功率预测模型。首先,利用VMD分解算法将历史风电功率序列分解成若干个子模态分量,根据计算的PE值重构分解的子模态风电分量;然后,使用特征注意力(feature attention,FA)机制和深度残差级联网络(deep residual cascade network,DRCnet)构建MulitiBiLSTM预测模型,预测重构后的子序列;最后,重构子序列预测值,得到最终风电功率预测结果。使用贵州某风场的数据集对所提出的方法进行验证,并和其他预测模型进行对比。结果表明,使用VMD-PE-MultiBiLSTM模型能显著降低风电功率预测误差。 展开更多
关键词 风电功率超短期预测 变分模态分解(VMD) 排列熵(pe) 多层双向长短时记忆(MultiBiLSTM)
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Creating the Role of Rural Teachers as New Rural Sages under the Background of Rural Revitalization Based on Organizational Change and Planned Happenstance Theories
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作者 LIN Jiangfeng YANG Shuai SHAN Yingyu 《Journal of Landscape Research》 2023年第6期65-68,72,共5页
In the context of rural revitalization,people are re-examining the issue of creating the role of teachers as“new rural sages”.However,most of previous studies ignored the school organizational change in the process ... In the context of rural revitalization,people are re-examining the issue of creating the role of teachers as“new rural sages”.However,most of previous studies ignored the school organizational change in the process of reform.The planned happenstance suggests that teachers should maintain a positive mindset about the eventualities in their careers.Based on the organizational change theory,this paper gave some advice to help teachers in playing a role of new rural sages:①rooting in local culture and enhancing teachers’sense of belonging,②providing compensation for teachers in a targeted way,and③providing a comprehensive and objective evaluation mechanism for ensuring teachers’participation in social governance. 展开更多
关键词 Rural teacher School organizational reform Planned happenstance theory New rural sage
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磺化热压PE无纺布的性能研究
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作者 徐志成 张伟政 +5 位作者 王军波 万思青 王志勇 刘振民 王旭梅 姜永锡 《膜科学与技术》 CAS CSCD 北大核心 2024年第2期107-111,共5页
利用磺化反应及热压处理,化学改性聚乙烯(PE)无纺布的亲水性和离子交换能力,讨论了时间、温度、热压压力等不同反应条件对材料力学性能的影响,使用显微镜(SEM)对磺化前后PE无纺布的外表状态进行观察,磺化后无纺布表面磺化效果有效提高.... 利用磺化反应及热压处理,化学改性聚乙烯(PE)无纺布的亲水性和离子交换能力,讨论了时间、温度、热压压力等不同反应条件对材料力学性能的影响,使用显微镜(SEM)对磺化前后PE无纺布的外表状态进行观察,磺化后无纺布表面磺化效果有效提高.实验结果表明,PE无纺布的亲水性和离子交换水平在反应温度为85℃,热压压力为8 MPa,反应时间为2 h的磺化反应条件下,不仅PE无纺布的亲水性和离子交换能力得到了显著的改善,而且拉伸性能和耐腐蚀性能得到了较好保留. 展开更多
关键词 pe 磺化反应 亲水性 离子交换能力
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PE改性沥青多尺度流变性能
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作者 李旭瑞 《石家庄铁道大学学报(自然科学版)》 2024年第1期114-120,共7页
为评价PE(聚乙烯Polyethylene,简写PE)改性沥青流变性能及不同流变指标之间相关性,基于不同PE改性剂掺量下的动态剪切流变试验和多应力蠕变恢复试验,以车辙因子、Shenoy参数、低剪切黏度、不可恢复蠕变柔量和蠕变恢复率作为PE改性沥青... 为评价PE(聚乙烯Polyethylene,简写PE)改性沥青流变性能及不同流变指标之间相关性,基于不同PE改性剂掺量下的动态剪切流变试验和多应力蠕变恢复试验,以车辙因子、Shenoy参数、低剪切黏度、不可恢复蠕变柔量和蠕变恢复率作为PE改性沥青流变性能多尺度评价指标,分析不同流变指标相关性;以老化指数和Cole-Cole图评价PE改性剂对沥青耐老化性能和黏弹性的影响.结果表明,随着PE改性剂掺量增加,车辙因子、低剪切黏度、Shenoy参数和蠕变恢复率逐渐增加,且后三者与车辙因子呈正相关;不可恢复蠕变柔量逐渐降低,且与车辙因子呈非线性负相关.车辙因子与其余流变参数相关系数均在90%以上.PE改性沥青耐老化性能及弹性提高.PE改性剂掺量大于6%时,流变指标及老化指数受改性剂掺量影响幅度降低. 展开更多
关键词 道路工程 pe改性剂 沥青 流变 多尺度
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Development and validation of a novel questionnaire regarding vision screening among preschool teachers in Malaysia
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作者 Shazrina Ariffin Saadah Mohamed Akhir Sumithira Narayanasamy 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第6期1102-1109,共8页
AIM:To develop and evaluate the validity and reliability of a knowledge,attitude,and practice questionnaire related to vision screening(KAP-VST)among preschool teachers in Malaysia.METHODS:The questionnaire was develo... AIM:To develop and evaluate the validity and reliability of a knowledge,attitude,and practice questionnaire related to vision screening(KAP-VST)among preschool teachers in Malaysia.METHODS:The questionnaire was developed through a literature review and discussions with experts.Content and face validation were conducted by a panel of experts(n=10)and preschool teachers(n=10),respectively.A pilot study was conducted for construct validation(n=161)and test-retest reliability(n=60)of the newly developed questionnaire.RESULTS:Based on the content and face validation,71 items were generated,and 68 items were selected after exploratory factor analysis.The content validity index for items(I-CVI)score ranged from 0.8-1.0,and the content validity index for scale(S-CVI)/Ave was 0.99.Internal consistency was KR^(2)0=0.93 for knowledge,Cronbach’s alpha=0.758 for attitude,and Cronbach’s alpha=0.856 for practice.CONCLUSION:The KAP-VST is a valid and reliable instrument for assessing knowledge,attitude,and practice in relation to vision screening among preschool teachers in Malaysia. 展开更多
关键词 validity RELIABILITY preschool teachers vision screening QUESTIONNAIRE
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