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厚尾噪声条件下星凸形扩展目标student’s t滤波器 被引量:3
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作者 陈辉 张星星 杨文瑜 《兰州理工大学学报》 CAS 北大核心 2021年第5期85-92,共8页
针对非线性非高斯厚尾噪声条件下的不规则形状的扩展目标跟踪问题,提出了基于随机超曲面模型(RHM)的星凸形扩展目标student’s t滤波算法.首先,在带有非高斯厚尾过程噪声和厚尾量测噪声的系统中,基于student’s t分布给出鲁棒student’... 针对非线性非高斯厚尾噪声条件下的不规则形状的扩展目标跟踪问题,提出了基于随机超曲面模型(RHM)的星凸形扩展目标student’s t滤波算法.首先,在带有非高斯厚尾过程噪声和厚尾量测噪声的系统中,基于student’s t分布给出鲁棒student’s t滤波器.其次,利用随机超曲面模型描述任意星凸形扩展目标的量测源分布,提出带厚尾噪声的星凸形扩展目标student’s t滤波器.最后通过仿真验证了所提方法的正确性和有效性. 展开更多
关键词 扩展目标跟踪 随机超曲面模型 鲁棒student’s t滤波器 student’s t分布
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扩展目标跟踪Student’s t逆Wishart平滑算法 被引量:2
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作者 陈辉 张丁丁 +1 位作者 连峰 韩崇昭 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第8期3353-3362,共10页
脉冲干扰和离群量测信息等因素通常会导致异常的厚尾噪声,这使得以高斯假设为前提的扩展目标跟踪(ETT)估计器的性能急剧降低,针对该问题该文提出一种基于扩展目标随机矩阵模型(RMM)的Student’s t逆Wishart平滑(StIWS)算法。首先,将目... 脉冲干扰和离群量测信息等因素通常会导致异常的厚尾噪声,这使得以高斯假设为前提的扩展目标跟踪(ETT)估计器的性能急剧降低,针对该问题该文提出一种基于扩展目标随机矩阵模型(RMM)的Student’s t逆Wishart平滑(StIWS)算法。首先,将目标的运动状态以及过程噪声和量测噪声建模为Student’s t分布以表征异常噪声对扩展目标概率分布的影响,将目标扩展状态建模为服从逆Wishart分布的随机矩阵。然后,在Student’s t贝叶斯平滑框架下,详细推导了能在扩展目标的多重特征动态演变的过程中有效估计目标状态的StIWS算法。最后,通过扩展目标跟踪的仿真实验结果和真实场景实验结果验证了所提算法的有效性。 展开更多
关键词 扩展目标跟踪 student’s t平滑 逆Wishart分布 厚尾噪声
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带厚尾噪声的鲁棒Student’s t容积滤波器 被引量:1
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作者 程然 缪礼锋 王婷婷 《控制理论与应用》 EI CAS CSCD 北大核心 2019年第7期1174-1181,共8页
为了解决带厚尾过程和量测噪声的非线性状态估计问题,本文提出了一种新的鲁棒非线性滤波器.首先,对带厚尾过程和量测噪声的非线性系统进行了数学建模,并推导了基于Student’s t近似的鲁棒非线性滤波器(RSTNF)的一般结构.其次,针对RSTNF... 为了解决带厚尾过程和量测噪声的非线性状态估计问题,本文提出了一种新的鲁棒非线性滤波器.首先,对带厚尾过程和量测噪声的非线性系统进行了数学建模,并推导了基于Student’s t近似的鲁棒非线性滤波器(RSTNF)的一般结构.其次,针对RSTNF中涉及到的含有关于Student’s t分布的多维非线性函数积分的求解问题,提出了基于Student’s t分布的球径容积准则(STSRCR),并在此基础上设计了一种新的鲁棒Student’s t容积滤波器(RSTCF).最后,利用目标跟踪仿真验证了本文提出的带厚尾噪声的RSTCF的有效性以及与现有方法相比的优越性. 展开更多
关键词 非线性状态估计 厚尾噪声 student’s t分布 三次幂球径容积准则 鲁棒student’s t容积滤波器
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Internet: A Fresh Motivation to EFL Students?—— Does It Motivate EFL Students
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作者 杨倩 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2002年第S3期106-109,共4页
This paper explores the hypothesis that using a computer network for real - synchronous discussion has noticeable effects on EFL students’ motivation language learning. Three motives emerge from the students’ respon... This paper explores the hypothesis that using a computer network for real - synchronous discussion has noticeable effects on EFL students’ motivation language learning. Three motives emerge from the students’ responses to a survey:chatting on the Internet provides an opportunity for "real" communication; it improves personal confidence. It encourages students to overcome writing apprehension. Further analysis proves the hypothesis to a certain extent. 展开更多
关键词 MOTIVATION netchatting EFL studentS
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Teaching American Culture to Chinese Students
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作者 杨春泉 《黑龙江生态工程职业学院学报》 2007年第6期88-90,共3页
As an international language, English is now spoken by more and more people as a first, second or foreign language. The Chinese students tends to ignore the American culture when they are learning the language of Engl... As an international language, English is now spoken by more and more people as a first, second or foreign language. The Chinese students tends to ignore the American culture when they are learning the language of English. This paper puts forward the view that teaching American culture plays a significant role in helping the Chinese students learn English and the English teachers have the responsibility to teach American culture to Chinese students. 展开更多
关键词 AMERICAN CULTURE CHINESE studentS TEACHING
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量测随机延迟下带厚尾噪声的鲁棒Student’s t随机容积卡尔曼滤波器 被引量:5
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作者 卢春光 张永顺 +1 位作者 李志汇 葛启超 《电子学报》 EI CAS CSCD 北大核心 2019年第9期1830-1840,共11页
针对量测随机延迟下带厚尾过程噪声和量测噪声的非线性状态估计问题,本文通过充分考虑量测一步随机延迟特性及过程噪声和量测噪声的“厚尾”特性,推导了一种新的鲁棒Student’s t滤波器框架,并采用随机Student’s t-球面相径容积规则近... 针对量测随机延迟下带厚尾过程噪声和量测噪声的非线性状态估计问题,本文通过充分考虑量测一步随机延迟特性及过程噪声和量测噪声的“厚尾”特性,推导了一种新的鲁棒Student’s t滤波器框架,并采用随机Student’s t-球面相径容积规则近似计算Student’s t权值积分,从而设计了一种新的鲁棒Student’s t随机容积滤波器.首先,采用一组服从伯努利分布的随机序列来描述系统中可能存在的量测一步随机延迟现象,并采用Student’s t分布刻画过程噪声和量测噪声中存在的“厚尾”特性;其次,从理论上证明了当自由度参数趋于无穷以及随机延迟概率为零时,该鲁棒Student’s t滤波器就自动地降为标准的非线性高斯近似滤波器;最后,采用随机Student’s t-球面相径容积规则给出了一种新的鲁棒Student’s t随机容积滤波器,并通过协同转弯模型验证了该滤波器的有效性和优越性. 展开更多
关键词 随机延迟 厚尾噪声 student’st权值积分 伯努利分布 矩匹配方法 非线性估计
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基于Student′s t分布的不依赖子波最小二乘逆时偏移 被引量:14
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作者 李庆洋 黄建平 李振春 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2017年第12期4790-4800,共11页
最小二乘逆时偏移(Least-Squares Reverse Time Migration,LSRTM)与常规偏移相比具有更高的成像分辨率、振幅保真性及均衡性等优势,是当前研究的热点之一.震源子波的估计直接影响LSRTM结果的好坏,在实际情况下考虑到震源子波的空变特性... 最小二乘逆时偏移(Least-Squares Reverse Time Migration,LSRTM)与常规偏移相比具有更高的成像分辨率、振幅保真性及均衡性等优势,是当前研究的热点之一.震源子波的估计直接影响LSRTM结果的好坏,在实际情况下考虑到震源子波的空变特性,其估计十分困难.为了消除子波对LSRTM结果的影响,本文发展了基于卷积目标泛函的不依赖子波LSRTM算法.目标泛函由观测记录卷积模拟记录的参考道以及模拟记录卷积观测记录的参考道组成,由于观测子波和模拟子波在目标泛函的两项中同时存在,从而消除了子波的影响.此外,常用的基于L2范数拟合的LSRTM算法对噪声非常敏感,尤其是当地震数据中含有异常值时,常规LSRTM无法得到满意的结果.Student′s t分布相比L2范数具有更好的稳健性,本文将其推广到不依赖子波LSRTM中,提升了算法的稳健性,最后通过理论模型及实际资料试算验证了算法的有效性和对复杂模型的适应性. 展开更多
关键词 最小二乘逆时偏移 不依赖子波 student's T分布 目标泛函 卷积
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Student’s t滤波框架下的信息融合算法 被引量:1
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作者 吴骁航 马克茂 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2020年第3期581-588,共8页
针对多传感器系统的观测噪声为非高斯噪声的问题,通过Student’s t滤波框架和四元数特性相结合,以无迹变换计算Student’s t加权积分函数,设计基于Student’s t分布的无迹四元数滤波算法,作为局部滤波算法.利用拉格朗日乘子法计算最优... 针对多传感器系统的观测噪声为非高斯噪声的问题,通过Student’s t滤波框架和四元数特性相结合,以无迹变换计算Student’s t加权积分函数,设计基于Student’s t分布的无迹四元数滤波算法,作为局部滤波算法.利用拉格朗日乘子法计算最优融合权重系数,通过线性加权融合的方式,对各局部滤波结果进行融合.采用基于四元数的目标姿态运动模型进行仿真,利用3个星敏感器同时对同一目标进行观测,通过与已有的鲁棒无迹Student’s t滤波(RSTUF)算法对比,验证所提算法的有效性.仿真结果表明:所提算法在对目标姿态的估计精度、滤波收敛速度及收敛后的数值稳定性方面均高于RSTUF算法;通过多个观测信息互补,提高了估计精度及容错性. 展开更多
关键词 组合导航 student’s T分布 分布式融合 四元数 无迹四元数滤波
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非对称三参数Student-t分布的参数估计及应用 被引量:1
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作者 郝家岗 钱夕元 《统计与决策》 CSSCI 北大核心 2021年第11期25-29,共5页
文章基于t分布构造了一个新的非对称三参数Student-t分布。推导了新分布的累计分布函数、分位数函数、随机变量表达式和原点矩估计等基础性质,使用了矩方法、极大似然估计法和贝叶斯估计法等进行了参数估计,并通过生成模拟数据的方法比... 文章基于t分布构造了一个新的非对称三参数Student-t分布。推导了新分布的累计分布函数、分位数函数、随机变量表达式和原点矩估计等基础性质,使用了矩方法、极大似然估计法和贝叶斯估计法等进行了参数估计,并通过生成模拟数据的方法比较验证了三种方法的合理性。最后,将新分布代入实例中拟合,结果表明新分布相比其他的分布,在非对称和厚尾方面具有更好的拟合能力。 展开更多
关键词 偏态厚尾 非对称student-t分布 贝叶斯估计 数据拟合
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基于Student-t分布的混合模型图像分割方法 被引量:1
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作者 牛艺蓉 王士同 《计算机工程》 CAS CSCD 北大核心 2015年第10期204-209,共6页
传统图像分割方法在分割被重尾噪声污染的图像时的分割效果不理想。针对该问题,提出一种基于Student-t分布的图像分割方法。该方法根据像素间的空间关系,计算出其先验概率,使用梯度下降法优化参数,从而最小化误差函数,在参数优化后得到... 传统图像分割方法在分割被重尾噪声污染的图像时的分割效果不理想。针对该问题,提出一种基于Student-t分布的图像分割方法。该方法根据像素间的空间关系,计算出其先验概率,使用梯度下降法优化参数,从而最小化误差函数,在参数优化后得到像素点的后验概率值,对像素进行标记以实现图像分割。实验结果表明,在处理被重尾噪声腐蚀的图像时,与传统的K-均值、模糊C-均值等图像分割方法相比,该方法的误分率较低,分割效果较好。 展开更多
关键词 student-t分布 重尾噪声 图像分割 空间邻域关系 高斯混合模型
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Linguistic Insights into the Teaching of English Composition to Chinese College Students 被引量:4
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作者 冯翠华 《外语研究》 北大核心 1990年第1期46-51,共6页
How does one teach composition to Chinese college students of English? How does one teach thera to discover ideas for themselves and to put these into English patterns of thought and organization? Can the discovery of... How does one teach composition to Chinese college students of English? How does one teach thera to discover ideas for themselves and to put these into English patterns of thought and organization? Can the discovery of ideas really be taught? Is there a method of teaching whereby the scientific process of writing can be cornbined with the creative art of composition? 展开更多
关键词 Linguistic Insights into the Teaching of English Composition to Chinese College students
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Train Students to Solve the Practical Problem by Building Mathematics Models
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作者 ZHANGLian-zhong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2005年第1期91-93,共3页
It focuses on that students must be developed the ability to solve the practical problem by building the mathematics models and the ability to combine the theory with the practice. It also states that students must be... It focuses on that students must be developed the ability to solve the practical problem by building the mathematics models and the ability to combine the theory with the practice. It also states that students must be improved the learning interests and practical experience. 展开更多
关键词 mathematics models objective program train students
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Self-directed learning readiness and social problem solving of nursing students in Macao
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作者 Yuan Haobin 《护理学杂志》 CSCD 2016年第1期1-7,共7页
Objective The aims of this study were to describe nursing students′self-directed learning readiness and social problem solving and test their correlations in Macao.Methods This descriptive cross-sectional study was c... Objective The aims of this study were to describe nursing students′self-directed learning readiness and social problem solving and test their correlations in Macao.Methods This descriptive cross-sectional study was conducted on 140baccalaureate nursing students.A stratified random sampling was performed.The Self-directed Learning Readiness(SDLR)Scale and Chinese Social Problem-Solving Inventory-Revised(C-SPSI-R)were used.Results The response rate was 79.3%.Students possessed readiness for self-directed learning(mean 149.09±12.53,51.4%at high level,48.6%at low level).Regarding to social problem solving,the mean scores of each subscale were 9.35±3.25(Rational Problem Solving,RPS),10.26±3.23(Positive Problem Orientation,PPO),8.14±4.06(Negative Problem Orientation,NPO),5.67±4.44(Avoidance Style,AS),and 4.84±3.03(Impulsivity/Carelessness Style,ICS).SDLR was positively related to RPS and PPO,but was negatively related to AS.Conclusion Half of students possessed stronger readiness for self-directed learning.Students had a belief in the ability to solve problems,and adopted relevant strategies in solving problems.However,students still had negative and dysfunctional orientation and defective attempts in solving problems.Self-directed learning was positively related to positive and constructive orientation,but was negatively related to defective problem-solving pattern.Nurse educators should create educational climates for promoting student confidence and mutual responsibility for learning and their thinking process for problem solving. 展开更多
关键词 nursing student self-directed learning READINESS social problem solving MACAO
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Design and Validity Study on Oral English Assessment in Graduate Students 被引量:2
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作者 Zhang Yan Jia Linyu Hu Jiyue 《学术界》 CSSCI 北大核心 2013年第2期249-253,共5页
To explore the adoption of formative assessment in oral English test Validity study of oral test scores was performed in PhD candidates of 2011.Through linear relevance analysis,it is concluded that the relevance coef... To explore the adoption of formative assessment in oral English test Validity study of oral test scores was performed in PhD candidates of 2011.Through linear relevance analysis,it is concluded that the relevance coefficient between oral score and overall score is 0.751 (P <0.001),the relevance coefficient between oral score and listening score is 0.530 (P <0.001),and the results indicate overall score and listening score have a positive relevancy with oral score.The result showed a positive correlation of oral test scores with written examination scores.Questionnaires modeled with the 5-point Likert Scale revealed a moderate supportive attitude of students on this formative assessment.The results are:80.1% of students indicated they feel satisfied and very satisfied with such oral English evaluation form,77.9% of students consider this oral score reflects their real oral English proficiency.This indicates that most students feel satisfied about the form and score in this oral exam.Through effective combination between formative evaluation method and summative evaluation method,it can effectively coordinate the relation between teaching and learning in oral English teaching practice,stimulate students'study initiative,and play a positive role in improving students'overall oral English proficiency. 展开更多
关键词 英语学习 学习方法 阅读知识 课外阅读
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Nursing student perspectives of high-fidelity simulation in Macao 被引量:2
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作者 Haobin Yuan Beverly A Williams 《护理学杂志》 CSCD 2015年第7期1-5,共5页
Objective The purpose of this study was to explore student perspectives of high-fidelity simulation.Methods A descriptive study with semi-structured focus group interviews was conducted in Macao.Twenty-one focus group... Objective The purpose of this study was to explore student perspectives of high-fidelity simulation.Methods A descriptive study with semi-structured focus group interviews was conducted in Macao.Twenty-one focus group interviews were held with 113 baccalaureate nursing students who had experienced 36-hour of simulation.Results Students perceived that simulation created a nonrisk learning environment,and was helpful in knowledge and skill enhancement and nurse role understanding.However,lack of realistic interactions in psychosocial responses made it difficult for students to relate simulation experience to real-working situations,and poor group contributions affected their learning.ConclusionInteracting with a human patient simulator does not replicate the experience of working with a live patient.Tutors need to come up with ideas about how to make scenarios more real and give more forthright responses to improve the realism of psychosocial responses during simulation.Students experienced uncertainty with clinical decision making and commented on the minimal contributions of some group members.Tutors should be prepared to provide students with substantial supports in developing their understanding of simulation and engaging in the learning process. 展开更多
关键词 护理学 护士 护理方法 护理工作
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Effect of relaxation on the level of nursing internship students' stress
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作者 Ali Hassanpour Dehkordi Saeed Heydarnejad M 《海南医学院学报》 CAS 2010年第1期20-22,共3页
Objective: To explore how relaxation reduce the effect of stress in Iranian nursing students.Methods: A total of 40 nursing students were randomly selected and divided into two groups of test and control each with 20 ... Objective: To explore how relaxation reduce the effect of stress in Iranian nursing students.Methods: A total of 40 nursing students were randomly selected and divided into two groups of test and control each with 20 students.An exam questionnaire consisting of the stress test of Spilberger and control of physiological determinants(blood pressure,pulse respiration,temperature) was performed to two groups.The practice of relaxation continued for two weeks and three times a day.Data were collected and analysed using t-test and Chi-square.Results: Two groups did not show any difference in relation to the average of physiological determinants before and after investigation.However,pulse was significantly different between the two groups.The average scores of stress before and after relaxation were significantly differed between the two groups investigation so that the level of stress was reduced in the test group(t= 2.5,df =39,P= 0.02).Conclusion: To alleviate stressors associated with clinical practice and create a healthy work environment for practice it is recommended that nursing students have some relaxation before entering practical environments. 展开更多
关键词 护士 脉搏 生理因素 压力
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The Transmission of Huizhou Culture to Foreign Students in China-- Under the Context of Soft Power
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作者 Yao Yong 《学术界》 CSSCI 北大核心 2017年第5期296-304,共9页
Culture is an important aspect of soft power.Huizhou Culture is one of the best representations of traditional Chinese culture and has been attached great importance by scholars both at home and aboard.It's vitall... Culture is an important aspect of soft power.Huizhou Culture is one of the best representations of traditional Chinese culture and has been attached great importance by scholars both at home and aboard.It's vitally important to spread Huizhou Cultural values around the world to improve China's soft power.Foreign students in China are potential advocators of Chinese Culture.The cultural information they get will be transmitted to their own countries.We should take some strategies to promote Huizhou Culture among foreign students so that the charm of Huizhou Culture can be noticed and recognized by many more people. 展开更多
关键词 软实力 惠州培养 在中国的外国学生 学产
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Cultivation of Young Students' Core Value in New Media Environment
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作者 Zhang Xinbiao 《学术界》 CSSCI 北大核心 2016年第6期297-302,共6页
New media is not only an emerging media and a unique cultural form,but also a mechanismproducing,expressing and disseminating ideology such as the socialist core values.In the process of cultivating college students’... New media is not only an emerging media and a unique cultural form,but also a mechanismproducing,expressing and disseminating ideology such as the socialist core values.In the process of cultivating college students’core values,characteristics of new media such as information production,expression and propagation should be deeply understood and exploited.Accordingly,college students’positive values will be fully guided by new media,thus cultivating and shaping a new generation firmly fulfilling the socialist core values in China. 展开更多
关键词 价值观 新媒体 培养 生核 环境 意识形态 大学生 媒介
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Tea Art Education for Elementary School Students in Hangzhou City of Zhejiang Province in China——A Case of Caihe Second Elementary School
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作者 Kaori Shishido 《茶叶》 2013年第4期500-503,共4页
Caihe Second Elementary School,a public school in Hangzhou city of Zhejiang province in China,has shown excellent performance at practicing tea art education for students as a part of after-school activities it encour... Caihe Second Elementary School,a public school in Hangzhou city of Zhejiang province in China,has shown excellent performance at practicing tea art education for students as a part of after-school activities it encourages.In this paper,the author figured out significance of tea art in Chinese society by discussing " why elementary students learn Chinese tea art" through observation on tea art education at Caihe Second Elementary School and interview with persons involved. 展开更多
关键词 中国茶艺 艺术教育 小学生 杭州市 浙江省 案例 显示性能
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新发展阶段大学生成长为新型职业农民的影响因素评价 被引量:6
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作者 张成凤 谢治国 李洁 《西北农林科技大学学报(社会科学版)》 北大核心 2025年第1期140-150,共11页
乡村振兴战略的总目标是农业农村现代化,涉农高校肩负着为国家发展战略提供人才支持的重要使命。基于563份问卷数据和30份访谈资料,运用层次分析法与Matlab软件对涉农高校大学生成长为新型职业农民影响因素进行建模并求解。结果显示,涉... 乡村振兴战略的总目标是农业农村现代化,涉农高校肩负着为国家发展战略提供人才支持的重要使命。基于563份问卷数据和30份访谈资料,运用层次分析法与Matlab软件对涉农高校大学生成长为新型职业农民影响因素进行建模并求解。结果显示,涉农高校大学生成长为新型职业农民影响因素一级指标相关性排序为:社会因素>个体因素>家庭因素>学校因素;二级指标分析结果表明,职业收入、职业发展、家庭经济状况、职业人格特征、职业兴趣、职业价值观与专业背景对涉农高校大学生成长为新型职业农民的影响较大。基于此,提出建议。一是政府和社会要营造良好的舆论,改善工作环境及生产条件,提高新型职业农民经济收入;二是涉农高校应转变教育理念,以学生“个性发展”为取向,精准培养新型职业农民;三是家庭应优化教育环境,提升对乡村振兴战略的认识,支持大学生追求自己的职业理想;四是个人要提升乡村就业认识,存储就业创业知识,提高服务乡村振兴的能力。 展开更多
关键词 涉农高校大学生 新型职业农民 影响因素 评价
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