Christoph Rensing

AAA: a survey and a policy-based architecture and framework

The commercialization of the Internet has led to a large variety of business models based on Internet technology. Therefore, the demand for standardized and efficient solutions in support of reliable, secure, open, and flexible remote and mobile service accesses has increased. Existing authentication, authorization, and accounting systems still consider dedicated cases, but lack a generic approach. More general AAA services can be built by extending existing mechanisms and protocols for access scenarios other than dialup or PPP connections. While this work is performed mainly by the IETF AAA Working Group, another approach proposed by the IRTF AAAArch Research Group is termed AAA Architecture. This article surveys the state of the art in AAA and develops a new generic policy-based approach, A/sup x/, for AAA services and beyond, considering flexible levels of various services in an Internet service model, ranging from connectivity to content services.

Evaluating Recommender Systems for Technology Enhanced Learning: A Quantitative Survey

The increasing number of publications on recommender systems for Technology Enhanced Learning (TEL) evidence a growing interest in their development and deployment. In order to support learning, recommender systems for TEL need to consider specific requirements, which differ from the requirements for recommender systems in other domains like e-commerce. Consequently, these particular requirements motivate the incorporation of specific goals and methods in the evaluation process for TEL recommender systems. In this article, the diverse evaluation methods that have been applied to evaluate TEL recommender systems are investigated. A total of 235 articles are selected from major conferences, workshops, journals, and books where relevant work have been published between 2000 and 2014. These articles are quantitatively analysed and classified according to the following criteria: type of evaluation methodology, subject of evaluation, and effects measured by the evaluation. Results from the survey suggest that there is a growing awareness in the research community of the necessity for more elaborate evaluations. At the same time, there is still substantial potential for further improvements. This survey highlights trends and discusses strengths and shortcomings of the evaluation of TEL recommender systems thus far, thereby aiming to stimulate researchers to contemplate novel evaluation approaches.

Multigranularity reuse of learning resources

This article investigates a scenario of reuse in which existing learning resources serve as preliminary products for the creation of new learning resources. Authors should be able to reuse learning resources and also parts of them at different levels of granularity in a modular way. The requirements of multigranularity reuse are analyzed and compared to existing solutions. A concept for modular, multigranularity reuse is presented in this article. It is also shown how this kind of reuse can be achieved in practise.

A survey on pervasive education

Researchers and developers worldwide have put their efforts into the design, development and use of information and communication technology to support teaching and learning. This research is driven by pedagogical as well as technological disciplines. The most challenging ideas are currently found in the application of mobile, ubiquitous, pervasive, contextualized and seamless technologies for education, which we shall refer to as pervasive education. This article provides a comprehensive overview of the existing work in this field and categorizes it with respect to educational settings. Using this approach, best practice solutions for certain educational settings and open questions for pervasive education are highlighted in order to inspire interested developers and educators. The work is assigned to different fields, identified by the main pervasive technologies used and the educational settings. Based on these assignments we identify areas within pervasive education that are currently disregarded or deemed challenging so that further research and development in these fields are stimulated in a trans-disciplinary approach.

Extended explicit semantic analysis for calculating semantic relatedness of web resources

Finding semantically similar documents is a common task in Recommender Systems. Explicit Semantic Analysis (ESA) is an approach to calculate semantic relatedness between terms or documents based on similarities to documents of a reference corpus. Here, usually Wikipedia is applied as reference corpus. We propose enhancements to ESA (called Extended Explicit Semantic Analysis) that make use of further semantic properties of Wikipedia like article link structure and categorization, thus utilizing the additional semantic information that is included in Wikipedia. We show how we apply this approach to recommendation of web resource fragments in a resource-based learning scenario for self-directed, on-task learning with web resources.

Capture, Management, and Utilization of Lifecycle Information for Learning Resources

Throughout their lifecycle, learning resources undergo a multitude of processes by being created, used, provided or re-used. However, in order to be reusable, a learning resource often has to be adapted for a new context of use. This in turn implies multiple re-authoring processes being performed on a learning resource. During each of these processes different types of information emerge. When retained, this information can be helpful for the retrieval, authoring, use or re-use of learning resources thereafter. In this paper, the lifecycle of learning resources along with the information generated herein is analyzed and a distributed architecture proposed that allows for the capture, processing, management and utilization of the information mentioned in a generic way. Three steps have been conducted to implement the proposed framework. First evaluation results are promising.

Requirements and an architecture for a multimedia content re-purposing framework

Production of Learning Resources is very expensive. Hence re-use is a common way to lower these costs. In contrary to a re-use ”as is” re-purposing means to transform a Learning Resource to suit a new learning or teaching context. We consider re-purposing to be a promising approach to improve the re-use of Learning Resources. As a basis for re-purposing tools, a re-purposing framework shall provide fundamental functionality in order to facilitate the development of re-purposing tools. This paper analyzes the requirements for such a framework, proposes an actual architecture and presents the current state of the implementation.

Open Learning and Teaching in Educational Communities - Proceedings 9th European Conference on Technology Enhanced Learning EC-Tel 2014

ion of Learning Management Systems Instructional Design Semantics: A Meta-modeling Approach Applied to the Moodle Case-Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249 Esteban Loiseau, Pierre Laforcade, and Sebastien Iksal Exploring the Potential of Speech Recognition to Support Problem Solving and Reflection: Wizards Go to School in the Elementary Maths Cclassroom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263 Manolis Mavrikis, Beate Grawemeyer, Alice Hansen, and Sergio Gutierrez-Santos Social Network Sites as a Moderating Factor in E-Learning Platform Adoption: An Extension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277 Cayetano Medina and Ramón Ruf́ın Adapting Tutoring Feedback Strategies to Motivation . . . . . . . . . . . . . . . . 288 Susanne Narciss, Sergey Sosnovsky, and Eric Andres Table of

CROKODIL: a platform for collaborative resource-based learning

On-the-job learning is primarily a personal knowledge acquisition process accomplished increasingly based on resources found on the Web. These days, collaboratively learning from and with others on the Web is taking on a very prominent position in this learning process. CROKODIL aims to provide support for collaborative learning based on web resources. In this paper, we introduce our learning scenario and an evaluation of our target group. We describe our pedagogical concepts, and present the results of an evaluation of these concepts. CROKODIL supports the semantic tagging of resources as well as the collaborative use of these resources and their information. Social networking functionalities are integrated in the platform to encourage and support collaborative learning. We also present some extensions to the base functionality of the platform, such as resource recommendations and interfaces for the integration in existing learning management systems.

Automatic classification of didactic functions of e-learning resources

Re-use of digital resources is an important issue in e-Learning scenarios, because only intensive re-use can make e-Learning cost efficient. Besides reusing whole courses, authors often desire to re-use fine grained parts of courses for creating new Learning Resources. The granularity which appears to be most promising for this kind of re-use is the level of information objects. Information objects each have a dedicated didactic function; a set of information objects with different didactic functions are combined into Learning Objects. This paper analyzes how didactic functions of existing information objects can be automatically classified using machine learning technology. The results of such classification methods on a set of Learning Resources from medical science are discussed.