The Research On Conceptual Model Of Reusable Question And Information Framework Of Interoperation In The CAA

Computer assisted assessment (CAA), which is the use of computer to assess learning process, is becoming an important instrument in E-learning. A key element to CAA is question resource, so the development of question is so much important that huge investment should be needed. However, CAA is now hindered from some factors, such as questions not being reused easily, different systems not exchanging questions efficiently, which should be resolved urgently.This paper gives some solutions to above problems from two aspects of making best use of the existing questions-breaking through different subjects and cultures, strengthening communications and collaborations between systems-in order to shorten question development cycle, decrease investment and enrich question resource. On one hand, this paper studies how to improve question's reusability from the point of view of question's structure. Firstly, designs the common question usage scenario in CAA and finds that assessing process decides the question's structure, so the Four Process Model is introduced combined with the CAA characteristics. Secondly, analyzes information elements and their relationship in Four Process Model using OOA and then describes question representation. Lastly, provides BNF formal definition of the whole conceptual model and every sector. On the other hand, this paper studies how to improve system's interoperability from the point of view of constituting common specification (standard). Firstly, discusses the XML usage and establishes the logic structure of exchanged questions. Secondly, specifies the standardized content of exchanged questions, including elements, semantics and coding manner. Thirdly, defines metadata that is useful in question identification. Fourthly, rebuilds question taxonomy according question response type. Lastly, considers extension and conformance.At last, this paper describes the prototype system used to verify the theories in detail, such as architecture, functions and implementation, etc. The conclusion that theories are useful can be attained after running all kinds of cases, which are exhibited in the end.