【作者】 张波；

【导师】 朱新华；

【作者基本信息】 广西师范大学 ， 计算机应用技术， 2010， 硕士

【摘要】 随着网络技术的发展,现代远程教育在国内外得到了迅速发展,并在教育领域内被广泛地应用,业已成为当今国际国内教育的主流发展方向。但是,计算机网络的广泛性和复杂性使得现阶段网络教育的发展因诸多瓶颈而滞留不前,最为突出问题是学习资源的共享和不同学习系统之间的互操作性问题。解决这个问题的关键是制定远程教育技术规范,用标准化方法规范学习资源和学习系统,保障学习资源的可共享性和学习系统的互操作性。在众多国际组织发布的技术规范中,ADL的SCORM标准具有可访问性、协作性、持久性和重用性等优势,因而得到了广泛的支持和研究。现阶段,关于SCORM规范的研究集中于各类符合SCORM系统的开发、SCORM技术标准在各类远程课程学习的应用、符合SCORM的学习对象的检索技术、对SCORM模型的扩展研究、本体技术在SCORM学习环境中的应用等。本文分别从两个方向对SCORM规范展开研究:对SCORM内容聚集规范的扩展研究和基于SCORM规范的本体模型的构建,相关研究的贡献和创新点如下:(1)提出了基于函数组件的学习对象编列方法。提出该方法的是针对SCORM规范重用性和灵活性的不足为出发点。由于SCORM学习活动的描述中,表示课程结构的包装规范元素与表示课程编列功能的顺序规范元素混合使用,造成内容清单结构不清,可读性差。而且SCORM的组件重用机制只支持简单引用,无法根据上下文环境做出代码调整。本文的基于函数组件的学习顺序设计方法是在内容包清单中扩展一种函数元素(Function)来定义顺序组件,实现把编列功能元素从课程结构中分离出来单独描述。同时通过在内容结构的组织中扩展函数调用元素(Call)实现课程结构和编列功能的对应。通过改进原SCORM学习管理系统,证明该方法的可行性。(2)提出基于SCORM的学科知识库交换模型。把SCORM规范扩展到学习平台之间学科知识库交换的领域,并根据SCORM规范在表示学科知识结构的不足,提出了对SCORM的信息模型的扩展方法。该模型参照了SCORM信息模型,并根据学科知识库的实际与知识点相关理论,详细说明了如何应用SCORM模型来表示学习知识库,以促进学科知识库的标准化和解决学习系统之间知识库的互操作与可共享。(3)提出了基于SCORM规范的内容聚集本体模型。通过分析本体技术在E-learning中研究的最新进展和SCORM规范的XML绑定的特点,针对现有学习对象研究中缺乏学习活动的语义描述、SCORM信息模型XML绑定不能确切表示语义信息这两方面的不足,本文给出一个学习对象本体模型。该模型参照SCORM规范的内容聚集模型和SCORM的排列导航模型,用本体技术描绘学习对象中学习活动的编排和学习资源的组织信息。该本体模型包括元素分类和公理约束两部分。元素分类描述了SCORM模型所有的元素以及元素直接的关系。公理约束是一个形式化公理的集合,用于形式化描述对词汇分类中元素的语义约束。本文探讨使用本体技术作为SCORM模型语言的特点和可行性。并根据SCORM的模型元素、元素之间的关系和元素的语义约束,探讨使用本体构建SCORM模型,包括表示SCORM模型的概念、对象属性、数据类型属性、信息模型公理等。(4)探讨了基于SCORM规范的学习对象本体模型的实现技术。在分析各类本体构建语言优劣的基础上,选择OWL语言作为本体模型的表示语言,并且讨论了用OWL语言表述SCORM学习对象本体模型的具体方法,包括XML实体和名称空间、类的OWL定义、属性的OWL定义、值域约束公理OWL表示、必要性约束公理OWL表示、唯一性约束公理OWL表示、内容包装公理OWL表示和编列导航公理OWL表示等。在OWL表示SCORM概念和公理的基础上,讨论了SCORM学习对象的OWL表示与XML之间的转换方法,并以“规-例”教学方法为实例详细说明SCORM学习对象OWL模型化方法。最后,讨论了该学习对象模型在实际应用中的两种使用途径:开发完全支持本体技术的学习管理系统,以及对现有符合SCORM的学习管理系统进行扩展。并通过扩展SCORM 2004 3rd Edition Sample Run-Time Environment的课程导入模块,使该运行环境支持OWL表示的学习课程。更多还原

【Abstract】 With the booming development of network technology, the modern distance education has been rapidly promoted at home and abroad, and applied widely in the education field, as has become one of the mainstream education developments either international or domestic. Because of the universality and complexity of computer network, however, there still are many bottleneck problems on the development of distance education at the present, the toughest issues of which are sharing and interoperating learning resources among various learning systems. The key to solve this problem is the distance education technical specifications, which provide a series of standardized method of learning materials and learning platforms in order to ensure the shareablity and the interoperability of them. Among all kinds of specifications published by International Organizations, the SCORM specification, released by the ADL, has been get broad support and research at the current field because of its marked advantages such as accessibility, adaptability, affordability, durability, interoperability, reusability. At present, the research works on the ADL/SCORM are mainly centered on Development of tools or systems on SCORM, application of SCORM technology to various distance learning courses, retrieval technique of learning objects conformed to SCORM, extension of SCORM model, application of Ontology to the SCORM learning environment, etc. this thesis carries out the SCORM research mostly from two distances, extension research of the Content Aggregation Model of SCORM and construction of learning content ontology model based on SCORM. The contribution and innovation of this research show as follows:The first place, a learning content sequencing method based on the Function Components is proposed in this thesis. The method is designed with the purpose of improving the SCORM model’s reusability and flexibility in actual practice. Because the content packaging elements describing content structure is mixed in SCORM with the sequencing elements describing learning sequencing of the contents, there are some serious limitations in the definition of learning activities, such as unclear structure of the Content Organization, the lack of readability of the Content Manifest, etc.. Moreover, the SCORM reusing components can not support to adjust its parameters in response to changes of context, because the current mechanism for reusing components in SCORM is just simple reference of elements. The method presented by this thesis is to extend an element in the Content Manifest, called Function, which is used to define reusing sequencing components in order to separate sequencing elements from the content structure. At the same time, this method requires to extend a function-call element, called Call, which is designed for content elements to reference defined components.The second place, this thesis put forward a Domain Knowledge Base Exchange Model based on SCORM. Its technical innovation is to extend the application of SCORM model into the domain knowledge base field. The design of this model is dependent on the related instructional theory on the domain knowledge base and SCORM Content Aggregation Model. In the model, the SCORM not only acts the role of the model principle but also is extended in according with the practical feature of knowledge base in this thesis. This thesis specifies the details about how to use the SCORM model for representing the learning domain knowledge model so as to standardize the domain knowledge base for its interoperability and shareablity among different learning systems.The third place, this thesis presents a content aggregation Ontology model based on SCORM. By analyzing the latest E-learning research of ontology technology and the features of SCORM XML banding, this thesis provides a learning ontology model. The model is designed for overcoming the shortcomings that existing SCORM XML information model can not provide specific semantic information for the SCORM. This model, based on the SCORM Content Aggregation Model and the SCORM Sequencing & Navigation Model, provide a ontology method to define in content object how to sequence learning activities and how to organize learning resources in ontology. This model concludes element hierarchies and constraint axioms. Among them, the element hierarchy defines all of the SCORM elements and relationships between them. The constraint axiom is a set of formal axiom that axiomatically describes the semantic constraints of elements in the element hierarchies. This thesis investigates the feasibility and advantage of ontology SCORM information model that regard the ontology language as SCORM model language. Moreover, based on SCORM elements, attributes, relationships, and semantic constraints on them, the author discusses how to use ontology technology to make up the SCORM information model, which include SCORM model’s class, object properties, data type properties, information model axiom, and etc.The fourth place, this thesis discusses the implementation technique of the ontology SCORM learning object model. By analyzing and comparing all kinds of ontology languages, language OWL is selected as the model building language of the SCORM ontology model. Then, this thesis discusses the specific methods to build the ontology model in OWL, which includes how to define XML entities, namespaces, classes, properties, range restriction axioms, necessity restriction axioms, uniqueness restriction axioms, content packaging axioms, sequencing & navigation restriction axioms, etc.. Based on the representation of OWL, this thesis advances the conversion methods of SCORM learning object between in XML and in OWL. Moreover, an example is taken to explicate the method of modeling the SCORM objects. Finally, there are two ways to apply the ontology learning model in practice, which are the development of full ontology-supporting Learning Management Systems (LMSs) and the extension of existing LMSs for supporting ontology. The program of this thesis has practiced the OWL LMSs by the means of extending the Importing Course Module of the SCORM 2004 3rd Edition Sample Run-Time Environment.更多还原