Connecting distance learning communities to research via virtual collaboratories: a case study from library and information science     

Kristen Rebmann 《Open Learning》2013,28(3):273-282

This case study reports on patterns of participation in a virtual collaboratory organised around goals associated with the involvement of graduate students in research and writing projects. Traditionally, distance learning classrooms have been devoted to teaching content matter (in a virtual context) yet this case study reports on the use of synchronous learning contexts to support research and professionalisation on the part of graduate students in library and information science. Focus is placed on discussing virtual collaboratories as a form of learning design that modifies the use of existing (synchronous) distance learning classrooms.  相似文献   

Maintaining Research Documents with Database Management Software     

《学校用计算机》2013,30(3-4):67-80

Summary

This article reviews the development and delivery of a Higher Education course module as part of a large European University's Integrated Masters Program operating through a regional network of Rural Area Training and Information Opportunities (RATIO) telematic centres. The aim of the project was to provide remote learners living in the southwest of England with computer-supported solutions to access higher education as part of a technology-assisted distance education program. The module represented a shift from traditional educational delivery systems by using instructional courseware via an Internet Web site. Personal communications with module participants were conducted with the use of e-mail and videoconferencing information technology (IT) resources. Out of the original sixteen participants who enrolled in this Masters course module, four actually completed the learning sessions and two submitted final assignments. This article considers the key lessons learned from this attrition rate and shares the mainly positive experiences of the remote tutor and the students engaged in this initiative. The implications regarding the use of the Internet for delivering higher education course modules through online distance learning are discussed in the light of cautions learned from this research project and important practical recommendations for future practice are made.  相似文献   

基于ANSOFT的永磁同步电机电磁场分析     

敖晖  郑乃清 《宁德师专学报(自然科学版)》2013,25(3):228-231

电机气隙是机电能量转换的重要区域,气隙中的磁通密度是电机设计的重要参数．对7．5kW永磁同步电机,通过有限元分析软件ANSOFT进行建模、定义材料属性和模型属性,经过剖分划网、加载边界条件和负载电流,求解偏微分方程组后,完成后处理,得到永磁同步电机气隙中的磁力线分布图和磁通密度分布图．分析结果为永磁同步电机的优化设计提供指导意义．  相似文献   

基于滑模直接转矩控制磁阻同步电机的仿真研究     

王鹏飞  刘芬 《顺德职业技术学院学报》2009,7(1):22-24

ALA转子电机具有与普通电机不同的结构,但与普通电机一样,直接转矩控制也能改善其动态性能和抗干扰能力,同时也存在较大的电流、磁链和转矩脉动,逆变器开关频率不恒定,高频噪声等问题、为此,在速度PI调节器中采用了具有快速响应,对参数变化及扰动不灵敏的滑模变结构控制,仿真结果表明有很好的效果。  相似文献   

基于 PPG 信号的 LSTM 网络同步动脉血压预测     

李帆  程云章  边俊杰  耿晓斌 《教育技术导刊》2009,19(8):44-48

为通过光电容积脉搏波信号获取动脉血压参数,并将其作为判断个人健康状况的依据,基于 Tensorflow框架训练 LSTM 网络模型与传统 RNN 模型,使用 625 000 条光电容积脉搏波数据序列通过忘记、选择记忆、输出阶段得出符合生理规律的血压参数,将两种模型放在 125 000 条样本的测试集中进行有效性验证。实验结果表明,训练后的 LSTM 模型对血压的预测比传统 RNN 模型更准确,LSTM 预测评价指标 MAE、RMSE、STD 和 R2_score 分别为 4.05、8.78、7.42 和 0.89,且预测结果符合美国医疗仪器促进协会标准（MAE<5mmHg,STD<8mmHg）,而传统 RNN 模型则为 11.58、17.03、14.54 和 0.73。LSTM 模型能较好地预测血压参数,在生物医学领域有较高的应用价值,其效果优于传统 RNN 模型。  相似文献   

Differences in electronic exchanges in synchronous and asynchronous computer-mediated communication: the effect of culture as a mediating variable     

Charoula Angeli  Neil H. Schwartz 《Interactive Learning Environments》2016,24(6):1109-1130

Two hundred and eighty undergraduates from universities in two countries were asked to read didactic material, and then think and write about potential solutions to an ill-defined problem. The writing was conducted within a synchronous or asynchronous computer-mediated communication (CMC) environment. Asynchronous CMC took the form of email exchanges between American learners only, Southern European learners only, and American and Southern European learners together. Synchronous CMC was restricted to dyads consisting of American–American, Southern European–Southern European, and American–Southern European students dialoguing. Additionally, a number of Americans and Southern Europeans were each paired with a content-“mirroring” computer-generated partner to account of the effect of thinking with an unresponsive partner in synchronous CMC. Results revealed that dyadic learners in asynchronous CMC used significantly more reasoning skills to think about solutions to the problem, while dyadic learners in synchronous CMC exchanged significantly more personal knowledge and features of emotion. However, the tendency among dyadic learners to include emotional features in their dialogues was mediated by their cultural background.  相似文献   

基于FPGA的10 Gbit/s伪随机序列测试装置     

苗澎  王志功 《东南大学学报》2007,23(4):516-519

介绍了一种基于FPGA的可编程SONET OC-192 10 Gbit/s伪随机序列发生器和比特间插入奇偶校验码BIP-8的误码测试仪.该误码测试仪为并行反馈结构,可生成PRBS序列长度为27-1,210-1,215-1,223-1和231-1,通过SFI-4接口,采用10 Gbit/s收发一体光模块,其工作速率可达10 Gbit/s.在OC-192帧同步调整电路中,采用STM-64/OC192二分查找法的帧同步法,显著提高了帧同步速度并减少了帧同步逻辑的复杂度.该系统可作为一种低成本的测试仪评估OC-192-设备与器件,以取代昂贵的商用PRBS测试仪.  相似文献   

Synchronous discussion between assessors and assessees in web-based peer assessment: impact on writing performance,feedback quality,meta-cognitive awareness and self-efficacy     

Lanqin Zheng  Panpan Cui  Xin Li  Ronghuai Huang 《Assessment & Evaluation in Higher Education》2018,43(3):500-514

Research on peer assessment in higher education has been conducted for decades. However, ways to improve the quality of peer feedback and optimise student’ benefits through peer assessment remain a puzzle. The present study aimed to examine the impacts of synchronous discussion between assessors and assessees on writing performance, qualitative feedback quality, meta-cognitive awareness and self-efficacy in web-based peer assessment. A total of 64 undergraduate students participated in the study and were randomly assigned into either the experimental or control group. Participants in the experimental group conducted synchronous discussion after the first round of peer assessment, while students in the control group did not conduct any synchronous discussion. The results revealed that synchronous discussion between the assessors and assessees significantly improved the students’ writing performance, especially content writing skills, affective and meta-cognitive feedback quality, meta-cognitive awareness and self-efficacy. Practical implications, limitations and future directions are discussed based on these findings.  相似文献   

心电图检测与辨识的人工神经网络方法     

刘尚明  潘燕  李桥  张玉华  张延  孙文红  李新 《实验室研究与探索》2005,24(11):15-16,80

应用人工神经网络（Artificial Neural Network，ANN）算法对MIT-BIH心电数据库中的数据进行检测，对波形辨识算法做初步研究。设计三层神经网络结构：输入层、隐含层和输出层。从心电信号中提取4项特征参数作为输入层的输入量，并对MIT-BIH心电数据库中的15例心电数据进行了检测。表明该算法对QRS波总体检测灵敏度为98．96％，检测真阳性率为99．93％，对室性异位博动检测灵敏度为94．97％，检测真阳性率为98．72％。实验证实该神经几乎络算法对心电波形辨识非常有效。  相似文献   

数字通信系统中导频同步信号处理技术研究     

王根平  文励洪 《深圳职业技术学院学报》2005,4(3):3-6

在数字通信系统中，各种干扰因素都能导致发送和接收信号之间产生同步偏差。通过对这种系统存在的信号同步偏差进行频域模型分析，提出了一种基于导频信号与数据信号之间的相角差的计算、对数据信号进行自适应同步调整的算法机制。实验证明，该种算法机制能有效地抑制和校正信号发送和接收之间的同步偏差，可充分保证数字通信系统的功能实现和通信性能。  相似文献