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Educational research over the past three years has intensified such that the context of learning resources needs to be properly modeled. Many researchers have described and even mandated the use of ontologies in the research being conducted, yet the process of actually connecting one or more ontologies to a learning object has not been extensively discussed. This paper describes a practical model for associating multiple ontologies with learning objects while making full use of the IEEE LOM specification. The model categorizes these ontologies according to five major categories of context based on the most popular fields of study actively being pursued by the educational research community: Thematic context, Pedagogical context, Learner context, Organizational context, and Historical/Statistical context. 相似文献
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个性化远程教学系统的模型研究 总被引:2,自引:0,他引:2
杨德华 《计算机工程与应用》2003,39(28):118-121
个性化远程教学系统是基于网络暨Internet技术的远程教学系统的最新发展。文章根据学习对象元和国际IEEEP1484LOM标准以及其他相关技术,提出了个性化远程教学系统的概念以及特征,并且依据NCEC项目实践,对于系统的层次模型、功能模型和数据模型进行了深刻的阐述与剖析。 相似文献
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Y.H. Guo Y.H. Yan X. R. Yan J. J. Chen S. Chen 《The International Journal of Advanced Manufacturing Technology》2003,21(8):596-603
Many technological difficulties exist in the field of rapid prototyping (RP) technology when making large-scale prototypes. The manufacturing efficiency is the main problem, and the process implemention and RP equipment also present difficulties. In this paper, the concept of divisional parallel scan is presented. Laminated object manufacturing (LOM) technology is used for the basic forming process and has been improved continuously through practice. Static divisional scan technology was also better developed to dynamic divisional scan technology, which can help in achieving the object of improving work efficiency and optimising design. 相似文献
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Ceramic green tape extrusion for laminated object manufacturing 总被引:2,自引:0,他引:2
Al2O3 and SiC green tapes with 0.2 mm thickness used for LOM (laminated object manufacturing) were prepared from a 75 wt.% ceramic suspension in a LDPE based organic vehicle followed by extrusion. Rheological characterization of the alumina and SiC suspensions were studied. TG-DTA analysis was carried out in air and microstructures were examined by SEM. 相似文献
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本文以LOM原型为基础,分别制作环氧树脂模型、硅胶模型、吸塑件模型石膏模型,并对这四种模型做电铸载体的可行性进行分析,在不影响电铸质量的前提下,根据不同结构特征可以选择合适的电铸载体。 相似文献
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快速原型技术现状与发展趋势研究 总被引:4,自引:0,他引:4
该文简要介绍了快速原型技术的原理、快速原型技术的特点,阐述了国内外现状及发展趋势。 相似文献
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现有的大尺寸薄壁机械零件自动化加工方法均存在着加工效率低、加工质量低的弊端,为了解决上述问题,引入LOM技术对大尺寸薄壁机械零件自动化加工方法进行设计与研究。根据大尺寸薄壁机械零件加工的特点采用LOM技术对加工目标曲面进行求解,以此为基础,采用截面线法对加工目标曲面信息进行提取,根据得到的加工目标曲面信息建立三维稳态切削力模型,以三维稳态切削力模型为依据,采用UG软件对数控机床加工程序进行编写与执行,实现了大尺寸薄壁机械零件的自动化加工。通过仿真对比实验得到,与现有的大尺寸薄壁机械零件自动化加工方法相比,提出的大尺寸薄壁机械零件自动化加工方法极大地提升了加工效率与质量,充分说明提出的大尺寸薄壁机械零件自动化加工方法具备更良好的加工性能。 相似文献