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991.
This two‐group, pretest‐posttest, quasi‐experimental study compared secondary students' learning of Algebra II materials over a 4‐week period when identical instruction by the same teacher was delivered through either embedded blended learning (treatment group; n = 32) or a live‐lecture classroom (control group; n = 24). For both groups, instruction was delivered in a normal classroom setting. A math test and a student survey were used to measure students' learning of Algebra II and satisfaction with the instruction. Students in the treatment group showed significantly greater gains in Algebra II test scores and evaluated their learning experiences significantly more positively than did the control group. The great majority (80%) of students in the treatment group preferred the embedded blended learning over traditional live lectures for future learning of math. Students' responses to open‐ended survey questions suggested that students in the treatment group appreciated the: (a) ability to control the pace of instruction; (b) new role of the classroom teacher; (c) lack of distraction in the blended learning environment; and (d) accessibility of the embedded multimedia lessons outside the classroom. This study suggests that screen‐capture instructional technology can be used towards establishing a teacher‐based, embedded blended learning environment within a secondary algebraic classroom. 相似文献
992.
Heath education is an important component of the curriculum for fostering children's correct health knowledge and good daily life habits. However, educators have indicated that most children might fail to realize the importance and meaning of health education content owing to the lack of authentic scenarios and daily life experience. With the advancement of computer technologies, researchers have tried to develop multimedia learning content in order to improve students' learning performance. Among various technology-enhanced learning alternatives, digital game-based learning has been recognized as a highly potential approach to motivating students. However, several previous studies have indicated that, without properly incorporating learning content into game scenarios, the effectiveness of digital game-based learning might not be as good as expected in comparison with conventional technology-enhanced learning. In this study, a contextual digital game was developed for improving students' learning performance in an elementary school health education course. A quasi experiment was conducted to evaluate the effectiveness of the proposed approach by situating the experimental group in the game-based learning scenario and the control group to learn with conventional e-books. The experimental results showed that the proposed approach not only improved the students' learning motivation, but also their learning achievement and problem-solving competences. Moreover, the significant two-way interaction suggested that the contextual game-based learning approach benefited the higher motivation students more than the lower motivation ones in terms of the advanced knowledge, showing the importance and potential of applying contextual games to health education activities. 相似文献
993.
A collegial practice transfer process between more- and less-experienced teachers was examined in two cases that sought to encourage teachers to use information and communication technology (ICT) in a pedagogically meaningful way. Collegial practice transfer aims to offer new models for in-service teacher training. The process included guiding sessions, training materials presenting authentic pedagogical examples, and try-outs in the classroom. The success of practice transfer was examined through comparing the classroom practices of more- and less-experienced teachers applying the Pedagogical Infrastructure Framework, and through analyzing the tutored teachers' self-reported experiences in interviews. The process provided flexible support and gave self-confidence to the less-experienced teachers. Technology use was successful, but the tutored teachers designed less coherent tasks and weaker support for pupils' collaboration, knowledge construction and metacognition than their more-experienced colleagues. When tutoring, underlying educational ideologies and reasons should be explicated in addition to practical issues of classroom orchestration and technology use. 相似文献
994.
Interactive high-performance computing is doubtlessly beneficial for many computational science and engineering applications whenever simulation results should be visually processed in real time, i.e. during the computation process. Nevertheless, interactive HPC entails a lot of new challenges that have to be solved – one of them addressing the fast and efficient data transfer between a simulation back end and visualisation front end, as several gigabytes of data per second are nothing unusual for a simulation running on some (hundred) thousand cores. Here, a new approach based on a sliding window technique is introduced that copes with any bandwidth limitations and allows users to study both large and small scale effects of the simulation results in an interactive fashion. 相似文献
995.
ContextA component-based software (CBS) system is a typical example of a composite component, which is composed of two or more atomic components. In the test of a CBS system, it is necessary to automatically generate expected results because they are compared with the actual results.ObjectiveThis paper proposes an automatic generation algorithm of expected results for the testing of a CBS system.MethodThe algorithm analyzes Input/Output (I/O) relationships of a CBS system to identify inputs that influence its outputs. Then, the algorithm uses test cases of atomic components for each input and automatically generates expected results. To evaluate the proposed approach, we compare the proposed approach with the other I/O relationship based approach via two case studies which are the CBS systems for guide robot. The comparison shows the effectiveness of our approach.ResultsTo verify effectiveness of the proposed approach, we measure the cost of manual generation of expected results for each case study. The costs are from 0.001 to 0.015 in the first case study, and are from 0.590 to 0.998 in the second case study.ConclusionThis proposed approach reduces the time-consuming and error-prone task which manually generates expected results for the testing of a CBS system. 相似文献
996.
997.
超声检查系统所呈图像中缺乏三维结构信息,且商业的医学图像分析软件价格昂贵。为此,开发一款综合病灶部位的三维模型和二维超声图像各自特征以及对应空间关系的检查系统。基于开源的医学图像处理软件、商用的电磁定位系统和超声成像系统,在局域网环境下,遵循OpenIGTLink协议进行数据共享的超声检查系统。该系统主要由超声图像信息共享模块、超声图像显示模块、超声探头实时跟踪模块、2D/3D配准融合模块组成。实验结果表明,该系统可初步应用于临床教学和临床辅助诊断等领域,具有价格低廉、扩展性强、维护方便等优势。 相似文献
998.
针对Lustre文件系统主要运用在高性能计算集群系统上的情况,分析Lustre文件系统的系统结构及其内部实现机制,测试系统在不同参数影响下的性能,认为Lustre可以运用在高性能集群系统上,也能运用在由普通计算机和 TCP/IP网络构建的集群系统上。实验结果表明,在TCP/IP协议和千兆交换机下, Lustre的并发性很难发挥,但设置合适的客户端数和系统参数可以优化其性能,相对本地磁盘系统, Lustre系统仍有较大的性能提高和实用价值。 相似文献
999.
Big data processing is becoming a standout part of data center computation. However, latest research has indicated that big data workloads cannot make full use of modern memory systems. We find that th... 相似文献
1000.
针对航空二次电源要求效率高、体积小、重量轻、高可靠性及实时性强的特点,研制了以F2812芯片为核心的嵌入式数字控制保护器,使DC/DC变换器实现自检测、健康预测和性能监控以及保护等功能.该保护器通过RS485总线与上位机进行信息交流,并将必要信息存储,同时阐述了试验过程中暴露的主要问题和解决措施,该保护器具有良好的工程应用价值. 相似文献