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21.
Gamification, the application of game elements to non-game settings, continues to grow in popularity as a method to increase student engagement in the classroom. We tested students across two courses, measuring their motivation, social comparison, effort, satisfaction, learner empowerment, and academic performance at four points during a 16-week semester. One course received a gamified curriculum, featuring a leaderboard and badges, whereas the other course received the same curriculum without the gamified elements. Our results found that students in the gamified course showed less motivation, satisfaction, and empowerment over time than those in the non-gamified class. The effect of course type on students' final exam scores was mediated by students' levels of intrinsic motivation, with students in the gamified course showing less motivation and lower final exam scores than the non-gamified class. This suggests that some care should be taken when applying certain gamification mechanics to educational settings. 相似文献
22.
目前广泛使用的同步发电机数字励磁调节器使用简单的单片机控制,采用PID(比例-积分-微分控制)+PSS(电力系统稳定器)控制策略,励磁调节器体积大,模块间干扰大,速度低,可靠性差,很难保证产品质量达到标准要求。为了弥补这个不足,采用PID(比例-积分-微分控制)+PSS(电力系统稳定器)+NOEC(非线性最优励磁控制)综合控制策略,把DSP(TMS320F2812)用于同步发电机数字励磁调节器中,具有通用性强、结构简单的特点,同时可以实现优良的控制效果。 相似文献
23.
针对城市场景车用白组织网VANET(Vehicular Ad Hoe Networks)的特性和车辆间通信时常中断的问题,在现有VANET路由协议的基础上,提出了一种改进的路由协议AAR。AAR基于实时交通流,能自适应选择路由,并能根据车辆的行驶速度、方向,对车辆位置进行精确预测。最后采用真实的城市道路场景,在NS2中进行了性能仿真,结果表明,与现有的VANET路由协议相比,性能有很大提高。 相似文献
24.
A new likelihood based AR approximation is given for ARMA models. The usual algorithms for the computation of the likelihood of an ARMA model require O(n) flops per function evaluation. Using our new approximation, an algorithm is developed which requires only O(1) flops in repeated likelihood evaluations. In most cases, the new algorithm gives results identical to or very close to the exact maximum likelihood estimate (MLE). This algorithm is easily implemented in high level quantitative programming environments (QPEs) such as Mathematica, MatLab and R. In order to obtain reasonable speed, previous ARMA maximum likelihood algorithms are usually implemented in C or some other machine efficient language. With our algorithm it is easy to do maximum likelihood estimation for long time series directly in the QPE of your choice. The new algorithm is extended to obtain the MLE for the mean parameter. Simulation experiments which illustrate the effectiveness of the new algorithm are discussed. Mathematica and R packages which implement the algorithm discussed in this paper are available [McLeod, A.I., Zhang, Y., 2007. Online supplements to “Faster ARMA Maximum Likelihood Estimation”, 〈http://www.stats.uwo.ca/faculty/aim/2007/faster/〉]. Based on these package implementations, it is expected that the interested researcher would be able to implement this algorithm in other QPEs. 相似文献
25.
In this paper, we describe an implementation of use in demonstrating the effectiveness of architectures for real-time multi-agent
systems. The implementation provides a simulation of a simplified RoboCup Search and Rescue environment, with unexpected events,
and includes a simulator for both a real-time operating system and a CPU. We present experimental evidence to demonstrate
the benefit of the implementation in the context of a particular hybrid architecture for multi-agent systems that allows certain
agents to remain fully autonomous, while others are fully controlled by a coordinating agent. In addition, we discuss the
value of the implementation for testing any models for the construction of real-time multi-agent systems and include a comparison
to related work.
相似文献
Robin CohenEmail: |
26.
Educational software games aim at increasing the students’ motivation and engagement while they learn. However, if software games are targeted to school classrooms they have to be usable and likeable by all students. Usability of virtual reality games may be a problem because these games tend to have complex user interfaces so that they are more attractive. Moreover, if the games acquire an educational content they may lose the attractiveness and appeal that they have on users who are familiar with commercial games. Consequently, likeability may also be questioned. In this paper, we address the issue of usability and likeability of a virtual reality game that is meant to teach students geography. We describe the evaluation experiments conducted, which involved three categories of students in terms of their level of game-playing expertise: novice, intermediate and expert game players. The evaluation results showed that the game was indeed usable and likeable but there was scope for usability and likeability improvement so that the educational benefits may be maximised for all categories of students. The evaluation studies reported in this paper, revealed important issues about further research on virtual reality educational games. 相似文献
27.
Potential pedagogical benefits and drawbacks of multimedia use in the English language classroom equipped with interactive whiteboard technology 总被引:2,自引:1,他引:1
This paper analyses the process of multimedia integration in English language classrooms equipped with interactive whiteboard (IWB) technology, and offers insights into the theoretical underpinnings of multimedia use in language learning from the perspective of cognitive learning theory. The data discussed here are drawn from a study carried out as part of a PhD research programme at Lancaster University (UK). The study was conducted within an interpretative research paradigm, and data were collected and analysed according to a qualitative approach. In the first part, the paper discusses some perceived pedagogical benefits of adopting a multimedia-oriented approach in the IWB-based classroom. Secondly, it discusses a variety of potential problems related to the use of multimedia resources in the language classroom in question. Finally, the paper draws upon the literature on multimedia learning to address the potential pedagogical implications of these research findings. 相似文献
28.
Numerous educators have proposed the development of constructivist Internet-based learning environments for students. When creating the constructivist Internet-based learning environments, it is important for researchers to be aware of students’ preferences toward these environments. Through gathering data from 659 university students in Taiwan, this study developed a questionnaire to assess students’ preferences toward constructivist Internet-based learning environments. The questionnaire, with adequate validity and reliability, included 34 items on the following seven scales: relevance, multiple sources (and interpretations), challenge, student negotiation, cognitive apprenticeship, reflective thinking and epistemological awareness. The questionnaire responses revealed that male students tended to prefer the Internet-based learning environments where they could solve challenging problems, acquire cognitive apprenticeship and guidance from experts, and promote epistemological development than did female students. The findings also suggested that, if educators intend to develop Internet-based learning environments for more academically advanced students, such as graduate students, care should be taken to create more opportunities for them to negotiate ideas, obtain proper guidance, reflect their own thoughts, and explore epistemological issues. Finally, students with more Internet experiences tended to demand more on many features of the constructivist Internet-based learning environments than those with less Internet experiences. 相似文献
29.
Using electric actuation and detection of oscillations in microcantilevers for pressure measurements
Gayatri Keskar Bevan Elliott Jay Gaillard Malcolm J. Skove Apparao M. Rao 《Sensors and actuators. A, Physical》2008,147(1):203-209
Response characteristics of a microcantilever, such as resonant frequency, amplitude, phase and quality factor, can be used for absolute pressure measurements in the range of 10−4 to 103 Torr. To this end, it would be very convenient to have the resonance of the microcantilever actuated and detected electrostatically. Herein, we report the nonlinear dynamics of microcantilevers under varying pressure and different gases using the harmonic detection of resonance (HDR) technique [J. Gaillard, M.J. Skove, R. Ciocan, A.M. Rao, Electrical detection of oscillations in 340 microcantilevers and nanocantilevers, Rev. Sci. Instrum. 77 (2006) 073907]. The HDR technique exploits nonlinearities in the cantilever-counter electrode system to allow electrostatic actuation and detection of the responses of the microcantilever to the pressure and gas composition. In particular, the 2nd and 3rd harmonics of the measured charge on the cantilever are investigated. The microcantilever demonstrates a quality factor of 10,000 at 10−3 Torr, and a usable response in the range from 10−3 to 103 Torr. The use of different harmonics can enable us to adjust the range of pressures over which the sensor has an efficacious response, enhancing its sensitivity to a particular environment. The experimental results are in reasonable agreement with theoretical calculations, despite the nonlinearities involved. 相似文献
30.
In recent years, we have witnessed a growing interest in the synchronous collaboration based class of applications. Several
techniques for collaborative virtual environments (CVE), haptic, audio and visual environments (C-HAVE) have been designed.
However, several challenging issues remain to be resolved before CVE and C-HAVE become a common place. In this paper, we focus
on applications that are based on closely coupled and highly synchronized haptic tasks that require a high-level of coordination
among the participants. Four main protocols have been designed to resolve the synchronization issues in such environments:
the synchronous collaboration transport protocol, the selective reliable transmission protocol, the reliable multicast transport
protocol and the scalable reliable multicast. While these four protocols have shown good performance for CVE and C-HAVE class
of applications, none of these protocols has been able to meet all of the basic CVE requirements, i.e., scalability, reliability,
synchronization, and minimum delay. In this paper, we present a hybrid protocol that is able to satisfy all of the CVE and
C-HAVE requirements and discuss its implementation and results in two tele-surgery applications.
This work is partially supported by Grants from Canada Research Chair Program, NSERC, OIT/Ontario Distinguished Researcher
Award, Early Research Award and ORNEC Research Grant. 相似文献