Jianmin Zhao

Advances in Web Based Learning - ICWL 2008

This book constitutes the refereed proceedings of the 7th International Conference on Web-Based Learning, ICWL 2008, held in Jinhua, China, in August 2008. The 52 revised full papers presented together with 1 invited paper were carefully reviewed and selected from 170 submissions. The papers are organized in topical sections on adaptation of e-learning technologies and policies, learning resource management, e-learning experiences, assessment and its supporting systems, tools and experiences for learning C programming language, game-based learning, frameworks and platforms for e-learning, multimedia technologies for learning, on-line discussion forum and community, collaborative learning, semantics and ontology, interfaces for learning activity designs, as well as mobile and network technologies for learning.

Multi-agent Framework Support for Adaptive e-Learning

In the past years, agent technology is considered one of the most innovative technologies for the development of software systems. Meanwhile, following the rapid development of Internet, particularly web page interaction technology, web-based learning has become increasingly popular. However, there not yet has a perfect framework in e-learning systems software designing. This paper proposes a multi-agent framework to realize an adaptive e-learning system. Experimental results indicate that applying the proposed framework for personalized e-learning system is feasible and robust.

OXML: an Object XML Database Supporting Rich Media Indexing and Retrieval

There are countless animation movies available nowadays throughout the Internet.xa0 Rich media (including Flash and PowerPoint) presentations are increasingly gaining widespread usage, particularly in the domains of e-learning and digital entertainment.xa0 In order to allow these animation movies to be queried efficiently, in this article we present OXML - an Object XML database for storing and retrieving animation movies. After converting the movies into XML format, OXML stores the resultant XML data into a native object-oriented database. To enhance the retrieval of such XML objects, an indexing technique known as Structural Join Index Hierarchy (SJIH) is then applied to the OXML database.xa0 A detailed cost model for query execution through SJIH is developed.xa0 Our experimental studies on accessing Flash movies using SJIH has demonstrated performance advantageous when compared with other indexing techniques.

A fuzzy quantization approach to image retrieval based on color and texture

This paper presents a new image retrieval method which is based on color and texture features. By using fuzzy quantization (which is based on a linear subjection function in the quantization of HSV color space), this method attempts to make the quantization results more accessible to human perception; furthermore, according to the information of the extracted dominant color of partition, we introduce a neighborhood color matrix which is used to describe the relative color spatial distribution, for the purpose of improving the robustness of image transfiguration. With the supplementary information of image textures, our method combines both the image and texture features to conduct composite image retrieval. Our experimental results show that this method can greatly improve the retrieval accuracy.

Multimedia Data Modeling Through a Semantic View Mechanism

The semantics of multimedia data, which features context-dependency and media-independency, is of vital importance to multimedia applications but inadequately supported by the state-of-the-art database technology. In this paper, we address this problem by proposing MediaView as an extended object-oriented view mechanism to bridge the “semantic gap” between conventional databases and semantics-intensive multimedia applications. This mechanism captures the dynamic semantics of multimedia using a modelling construct named media view, which formulates a customized context where heterogeneous media objects with similar/related semantics are characterized by additional properties and user-defined semantic relationships. Due to the complex ingredients and dynamic application requirements of multimedia databases, it is however difficult for users to define by themselves individual media views in a top–down fashion. To this end, a unique approach of constructing media views logically is devised. In addition, a set of user level operators is defined and implemented to accommodate the specialization and generalization relationships among the views. The usefulness and elegancy of MediaView are demonstrated by its application in a multi-modal information retrieval system.

New knowledge acquisition method in incomplete information system based on rough set and self-adaptive genetic algorithm

In this paper, a knowledge acquisition method is proposed in incomplete information system. Firstly, according to the rough set theory some improvement is made to the discernible matrix; then with integration of the self-adaptive genetic algorithm, a new knowledge acquisition algorithm to mine the consistent rules and inconsistent rules from the incomplete information system is presented. Furthermore, according to the study of confidence degree and support degree of association rule in complete information system, the rule confidence degree and support degree is defined within the framework of incomplete information system. Through the examination of experimental results, this algorithm is proved effective, especially to large incomplete information systems.

Igniting Students' Passion for Knowledge by Incorporating a Discovery Enriched Curriculum

One of the major challenges in tertiary education is to design the lectures such that students will be motivated to attend and get really interested which will ignite their passion for knowledge. For this regard, City University of Hong Kong has proposed to apply a discovery enriched curriculum DEC in developing teaching and learning activities to encourage students discover knowledge that is new to the students themselves. In this paper, we shared our experience about how the DEC was adopted in an introductory course on webpage programming to some freshmen students who had diverse technical backgrounds. Some webpage examples made by the instructor were used to stimulate students interest. These examples were designed so that they were related to students daily life to illustrate how things around them could be implemented in practice. The class has recorded a relative high attendance rate of around 75%. The relation between the average quiz marks and the number of lectures attended by the students was examined and the result indicated that the students who attended more lectures tended to obtain higher average quiz marks.

Distributed Sound Rendering for Distributed Virtual Environments

A distributed virtual environment allows remote users to communicate and interact with each other in a 3D environment through networks, in particular the Internet. Although existing work mainly focuses on visual communications, there is an increasing interest on audio communications too. The sound generation process is to modulate the input sound sources from the remote users or from some autonomous objects by the reverberation of the environment to produce the output sound. There are a few sound rendering methods proposed, with different applications, such as architectural simulation and online games. To improve the rendering performance, some of these methods employ parallel hardware architectures or dedicated sound processing hardware. In this paper, we propose a distributed sound rendering architecture for real-time sound rendering in a distributed virtual environment with moving observers and sound sources. We also propose the distributed prioritized sound rendering method to improve the rendering performance while preserving the perceptual quality. The new architecture has the advantages that it is based on low cost PCs and is scalable.

A personalized multimedia retrieval frame based on user interest

This paper describes a personalized multimedia retrieval frame based on user interest through the multi-model cross-mutual knowledge base. The most important feature of the frame is to integrate the multi- model data into a seamless retrieval system. It calculates both the semantic and content level similarity between media object and the query condition. And, using user interest model to push interesting information and sort the inquiry results, so that users can easily and quickly find interesting objects.

Mobile learning support with statistical inference-based cache management

Supporting efficient data access in the mobile learning environment is becoming a hot research problem in recent years, and the problem becomes tougher when the clients are light-weight mobile devices such as cell phones whose limited storage space prevents the clients from holding a large cache. A practical solution is to store the cache data at some proxies nearby, so that mobile devices can access the data from these proxies instead of data servers in order to reduce the latency time. However, when mobile devices move freely, the cache data may not enhance the overall performance because it may become too far away for the clients to access. In this paper, we propose a statistical caching mechanism which makes use of prior knowledge (statistical data) to predict the pattern of user movement and then replicates/migrates the cache objects among different proxies. We propose a statistical inference based heuristic search algorithm to accommodate dynamic mobile data access in the mobile learning environment. Experimental studies show that, with an acceptable complexity, our algorithm can obtain good performance on caching mobile data.