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941.
942.
The work aims to improve the assessment of creative problem-solving in science education by employing language technologies and computational–statistical machine learning methods to grade students’ natural language responses automatically. To evaluate constructs like creative problem-solving with validity, open-ended questions that elicit students’ constructed responses are beneficial. But the high cost required in manually grading constructed responses could become an obstacle in applying open-ended questions. In this study, automated grading schemes have been developed and evaluated in the context of secondary Earth science education. Empirical evaluations revealed that the automated grading schemes may reliably identify domain concepts embedded in students’ natural language responses with satisfactory inter-coder agreement against human coding in two sub-tasks of the test (Cohen’s Kappa = .65–.72). And when a single holistic score was computed for each student, machine-generated scores achieved high inter-rater reliability against human grading (Pearson’s r = .92). The reliable performance in automatic concept identification and numeric grading demonstrates the potential of using automated grading to support the use of open-ended questions in science assessments and enable new technologies for science learning. 相似文献
943.
Theodore Pachidis John Lygouras Kostas Tarchanidis 《Journal of Intelligent and Robotic Systems》2008,51(4):385-420
In this paper, first HumanPT architecture for low cost robotic applications is presented. HumanPT architecture differs than
other architectures because it is implemented on existing robotic systems (robot robotic controller) and exploits the minimum
communication facilities for real-time control that these systems provide. It is based on well-known communication methods
like serial communication (USB, RS232, IEEE-1394) and windows sockets (server–client model) and permits an important number
of different type of components like actuators, sensors and particularly vision systems to be connected in a robotic system.
The operating system (OS) used is Microsoft Windows, the most widely spread OS. The proposed architecture exploits features
of this OS that is not a real-time one, to ensure – in case that the robotic system provide such a facility – control and
real time communication with the robotic system controller and to integrate by means of sensors and actuators an important
number of robotic tasks and procedures. As implementation of this architecture, HumanPT robotic application and experimental results concerning its performance and its implementation in real tasks are provided.
HumanPT robotic application, developed in Visual C++, is an integrated, but simultaneously an open-source software that can be adapted
in different types of robotic systems. An important number of robotic tasks or procedures including sensors and particularly
vision systems can be generated and executed. Small enterprises by means of the proposed architecture and the open source
software can be automated at low cost enhancing in this way their production. 相似文献
944.
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
945.
网格应用程序执行时间预测系统 总被引:2,自引:0,他引:2
为了合理利用网格资源和改进应用程序的执行性能,需要对应用程序的执行时间进行实时预测,为任务调度系统和网格用户提供调度依据.本文工作建立了执行时间预测系统,周期性的产生预测信息并转换为统一格式注册到网格信息服务中.本文使用资源映射方法预测应用程序执行时间,并且设计一组实验测试系统性能.实验结果表明,本系统能够低开销,灵敏地预测执行时间,并且预测误差较小. 相似文献
946.
947.
948.
949.
VB是大家较熟悉的计算机编程语言,而在不少的应用软件中已嵌套了面向对象的VBA,如果能掌握了VBA的使用将会使工作效率达到事半功倍的效果,这对工程技术人员非常重要,该文简要介绍了VBA的使用方法。 相似文献
950.
电子白板是虚拟教室中的一个重要工具。该文介绍了基于JAVA语言设计的一个电子白板系统,并对电子白板的设计与实现过程当中的各种关键技术进行了讨论。 相似文献