In the earlier stage, a stepped vibrating seed sowing mechanism in the seed supply link of the precutting cassava seeder was designed. In order to further realize the precision seeding of cassava seed stems, a seed sowing mechanism was designed behind the stepped vibrating seed sowing mechanism to complete reliable seed filling and precision seeding. However, it was blind to take a single kind of stem from the cassava seed stem group that had been adjusted and sequenced through the seed metering mechanism scoop, which was easy to cause problems such as missing filling and reseeding. The spoon chain seed metering mechanism was further designed to solve the problems of seed filling difficulty and low seeding qualification index of the current precutting cassava precision seeder. The working principle of the seeder and the parameters related to the design of the spoon chain metering mechanism were described. Based on the theory of the fastest descent line, the parameters of the seed scoops of the metering mechanism were designed. The forces on the cassava seed stems and the motion state during the seed filling and seed feeding process of the mechanism were theoretically analyzed. It was determined that the significant factors affecting the seed filling performance were the type of seed scoops, the number of seed scoops, the motion speed of the conveyor chain, and the seed filling angle. Single factor simulation was carried out by using EDEM software, and the influence rules of different test factors on seed filling performance were obtained. The response surface BBD simulation test was carried out to determine the optimal factor parameter combination. The prototype seeder was developed for bench and field tests. The results showed that when the seed filling angle was 37°, the number of seed scoops was 12, and the moving speed of the conveyor chain was 0.63 m/s, the qualified index of seed filling was 93.8%, and the missed filling index was 1.9%. The field experiment showed that the spoon chain seed metering mechanism of the pre cut seed vibrating seed feeding cassava seeder had better performance and it can meet the agronomic requirements of precision cassava sowing.

针对木薯机械化种植过程中切种与播种等环节离散元仿真研究缺乏准确模型等问题,以桂热4号木薯为研究对象,利用试验及离散元模拟结合的方法对木薯种茎离散元仿真参数进行标定.先测定种茎基本物理参数,应用Hertz-Mindlin无滑动接触模型开展颗粒堆积虚拟试验,并结合圆筒提升法进行种茎堆积物理试验.通过2水平因子试验、最陡爬坡试验以及响应面分析确定种茎基本接触参数.在此基础上,应用Hertz-Mindlin with bonding接触模型开展种茎切断仿真试验,通过响应面分析颗粒切断离散元仿真参数.为验证标定参数准确性,通过侧壁坍塌试验进行参数验证,发现休止角的相对误差均小于2％,相对误差平均值为0.69％.研究结果表明,标定方法正确、仿真参数准确.

The application of non-cognitive factors represented by facial emotion in educational evaluation has attracted much attention in recent years. There are many existing studies on facial emotion assisted education evaluation, but most of them are based on virtual learning environments, which means that the research on facial emotion and learning effect in offline learning environments is sparse. In order to solve this problem, this study designed an emotion observation experiment based on the offline learning environment, obtained the type of learner facial emotion and learning effect of 127 college students, and further explored the relationship between the two. The results show that: 1) We obtained eight types of learner emotion through the combined description method: joy, relaxation, surprise, meekness, contempt, disgust, sadness, anxiety and their respective PAD emotional mean. 2) We obtained the correlation results of the six emotions of joy, relaxation, surprise, meekness, contempt, and anxiety with the learning effect and the predicted value of the learning effect. 3) We then constructed an explanatory model of learner emotion and learning effect based on the offline learning environment.

为深入研究我国中职教师教学能力研究现状,梳理和分析近年中职教师教学能力研究整体状况、发展脉络和研究热点,基于中国知网(CNKI)数据库,采用文献计量法对2011-2021年间国内关于中职教师教学能力研究文献进行归纳和分析.从研究现状来看,中职教师教学能力领域研究受到越来越多的关注,国内发文量总体呈上升趋势,且刊载量大的期刊多为职业教育领域优质期刊,大部分作者为独立研究,尚未形成紧密合作体系,研究机构呈现零散分布特点,且中东部地区发文量高于西部地区;从研究热点而言,主要集中在中职教师信息化教学、职业能力、创新能力、教学策略等能力提升上,且"互联网+教育"是近期研究热点.研究结果表明,中职教师教学能力总体研究质量虽不断提高,但仍存在不足,关于中职教师教学能力研究的成果缺乏系统理论指导,研究主体对象单一、不够全面,研究主题缺乏创新性.基于以上问题,从研究领域内部和外部分别提出展望,以期中职教师教学能力研究更具全面性.

探究一种结合创新实践能力培养与BYOD模式的新型教学模式,通过创新思想渗透、设置特定情境、组织探究任务、改变课程考核形式,突出创新、解决问题能力的培养,再通过以智能手机为主的BYOD模式,突破传统探究式教学的局限性,拓展课内课外的教学,形成创新实践能力培养与BYOD一体化教学模式.以"工业机器人"为例,设计教案并进行实践教学.结果表明,教学效果符合预期,课堂满意度高,能够实现高校学生的创新实践能力培养.

针对预切种播种器对成堆木薯种茎进行精密播种时待充木薯种茎乱序、充种可靠性低等难题,在播种器供种环节设计一种阶梯式振动散种机构.建立了木薯种茎在阶梯式振动散种机构上运动过程的数学模型,对木薯种茎相对散种板的下滑运动和其在阶梯式调姿板上的抛掷运动进行理论分析,确定显著影响机构性能的因素分别是作业宽度、振动频率、台阶倾角以及限位挡角.基于离散元法(Discrete Element Method,EDEM)建立了木薯种茎-振动散种机构的仿真模型,单因素仿真试验明确了各因素对横向调姿成功率和散种输送成功率的影响规律.研制了阶梯式振动散种机构试验台,进行四因素五水平正交中心组合试验研究,并基于最优的因素参数组合对4个不同品种的木薯进行适应性测试,确定最佳参数组合.结果表明当阶梯式振动散种机构的供种箱作业宽度为643.41 mm、振动频率为55.58 Hz、限位挡角为145.06°、台阶倾角为80.13°时,横向调姿成功率为85.7％,散种输送成功率为88.2％;当在最优因素参数组合下进行试验,横向调姿成功率为85.6％,散种输送成功率为88.6％.研究为预切种式木薯精密播种器相关装备的研制提供指导参考.