Showing papers by "Denis Gillet published in 2011"

Remote labs and social media: Agile aggregation and exploitation in higher engineering education

Abstract: This paper presents an agile aggregation and exploitation framework to provide access to remote laboratory experiments to higher engineering education students using a social media platform, namely Graaasp. The usage of this advanced social media enables educators or students to build personal learning environments that include invited peers, tutors or educators, aggregated or recommended resources, as well as online experiments and relevant simulation or data analysis services. The services and the experiments are accessible through simple widgets that can easily be implemented and that can intercommunicate with lightweight protocols such as RSS feeds. The proposed approach is illustrated with services supporting a control course taught at the Swiss Federal Institute of Technology in Lausanne (EPFL).

Contextual Spaces with Functional Skins as OpenSocial Extension

Abstract: Portability, flexibility and extensibility are essential features of social media platforms. When such Web platforms are able to take user's context into account, they provide better user experience and enhance the effectiveness of users' actions. In this paper, we discuss an extension to OpenSocial standard, namely contextual space, that shapes the framework, in which people carry out online activities. The proposed contextual space extension defines how a set of OpenSocial widgets are aggregated as a Web environment for a given purpose and with a given functional skin as a user interface. Additionally it allows to create contextualized widgets. In this paper we discuss the proposed extension in details and provide the examples of its use based on real life scenarios. Finally, we detail an implementation scheme.

May I suggest? Comparing three PLE recommender strategies

Abstract: Personal learning environment (PLE) solutions aim at empowering learners to design (ICT and web-based) environments for their learning activities, mashingup content and people and apps for different learning contexts. Widely used in other application areas, recommender systems can be very useful for supporting learners in their PLE-based activities, to help discover relevant content, peers sharing similar learning interests or experts on a specific topic. In this paper we examine the utilization of recommender technology for PLEs. However, being confronted by a variety of educational contexts we present three strategies for providing PLE recommendations to learners. Consequently, we compare these recommender strategies by discussing their strengths and weaknesses in general.

Trust-aware privacy control for social media

Abstract: Due to the huge exposure of personal information in social media, a challenge now is to design effective privacy mechanisms that protect against unauthorized access to social data. In this paper, a trust model for social media is first presented. Based on the trust model, a trust-aware privacy control protocol is proposed, that exploits the underlying inter-entity trust information. The objective is to design a fine-grained privacy scheme that ensures a user's online information is disclosed only to sufficiently trustworthy parties.

Preclinically assessed optimal control of postprandial glucose excursions for type 1 patients with diabetes

Abstract: Type 1 Patients with Diabetes (Type 1 PwDs) have to frequently adjust their insulin dosage to keep their Blood Glucose concentration (BG) within normal bounds. Meal intakes represent the most important disturbance that has to be accounted for. Its effect differs for every individual as well as for every meal. These specificities are automatically taken into account in the approach proposed in this paper. Model parameters are identified for every couple (Patient, Meal) of interest and optimal control is applied to generate individualized meal specific insulin profiles. The method does not require the use of a continuous BG meter, the profiles being infused in an open-loop manner. Results from a preliminary clinical study are presented. The concept is shown to be effective, despite limitations due to the aggressive execution chosen. Improvements are proposed and a possible practical implementation is described.

A Federated Search and Social Recommendation Widget

Abstract: This paper presents a federated search and social recommendation widget. It describes the widget’s interface and the underlying social recommendation engine. A preliminary evaluation of the widget’s usability and usefulness involving 15 subjects is also discussed. The evaluation helped identify usability problems that will be addressed prior to the widget’s usage in a real learning context.

A competence bartering platform for learners

Abstract: This paper introduces the concept of a currency-free competence exchange platform in the context of communities of self-regulated learners exploiting personal learning environments. In a life-long perspective, learners can be seen as potential teachers of the skills they collect and develop all along their experience. Currently, spontaneous assistance is a common practice but remains limited to acquaintance groups. Our goal is to foster the emergence of self-driven communities by enabling learners to make available or find competences, to arrange coaching sessions, and to get reusable credits in return. This paper details our investigations on competence models and decentralized credit systems on which the design of our Competence Bartering Platform is grounded.

Collision-free intersection crossing of mobile robots using decentralized navigation functions on predefined paths

Abstract: This paper deals with the coordination of a group of mobile robots at an intersection. It focusses on decentralized navigation functions (DNFs) to achieve efficient traffic control. The main challenge is to define virtual potentials, which are used by decentralized navigation functions, such that traffic is both fluent and safe, while taking into account real-world limitations like acceleration, braking and speed limits. Our method consists in defining the navigation function with respect to the desired acceleration profile and is accompanied by a set of visibility conditions that increase the capacity of the intersection in terms of vehicle throughput. Priority conditions have been used to both avoid blockades of robots and to save energy by assigning higher priorities to robots with higher inertias.

May I suggest? Three PLE recommender strategies in comparison

Abstract: Personal learning environment (PLE) solutions aim at empowering learners to design (ICT and web-based) environments for their activities in different learning contexts and even for transitions between these contexts. Hereby, recommender systems which are highly successful in other application areas comprise one relevant technology for supporting learners in PLE-based activities. In this paper we examine the utilization of recommender technology for PLEs. However, being confronted by a variety of educational contexts and due to different research approaches dealing with recommenders, we present three strategies for providing PLE recommendations to learners. Consequently, we compare these recommender strategies by discussing their strengths and weaknesses in general.

Exploring Trust in Personal Learning Environments

Abstract: The design of effective trust and reputation mechanisms for personal learning environments (PLEs) is believed to be a promising research direction. In this paper, we propose a 4-dimensional trust model that complies with the specific requirements of PLEs. Trust is explored in four dimensions: trustor, trustee, context and visibility. The importance of these four dimensions is investigated through a number of scenarios. The model is implemented in a PLE platform named Graaasp. Preliminary evaluation of usefulness is conducted through a user study and some interesting findings are discussed in the end.

A Minimal Exercise Extension for Models of the Glucoregulatory System

Abstract: For patients with type 1 diabetes mellitus, appropriate control of blood glucose concentrations is vital. Exercise is one of the disturbances that can affect these concentrations. Therefore, predictions in the presence of exercise are useful among others for model-based control methods, bolus calculators and educational tools. Although several models quantifying the effect of exercise are available, they generally include a high number of model parameters, which makes the identification a particularly challenging task, especially if only blood glucose measurements are available. In this paper, a new data-based minimal extension for existing models of the glucoregulatory system, which is able to account for the effect of exercise, is proposed. As observed from clinical data, for given exercise intensities and durations, the model does not depend on exercise intensity, making intensity measurements obsolete. Another main advantage is that this minimal extension involves the identification of only two additional scalar model parameters. The resulting model shows good agreement with the clinical data, and the obtained parameters are consistent between patients.

Introducing qualitative dimensions to analyse the usefulness of Web 2.0 platforms as PLEs

Abstract: The trends in web development of educational applications and of Web 2.0 or social applications are converging. Platforms are designed to host a variety of software components (called widgets or plugins), which can be organised or combined (mashed-up) at user's convenience. Such platforms can be exploited as both personalised learning environment (PLE) and as social network applications. This article argues that six qualitative dimensions can be defined to analyse the main features of these platforms: the screen dimension measures the visual integration, the data dimension measures the portability of data, the temporal dimension measures the rate of data synchronisation, the social dimension measures the networking of users, the activity dimension measures the structuring of users' interactions with the environment, and the runtime dimension measures the flexibility in accessing the environment from different end points. As a proof of concept of the introduced dimensions, a few familiar Web 2.0 platforms are first measured along each dimension and then, using the results visualised as spider diagrams, compared with respect to their usefulness as PLEs.

1st Workshop on Exploring the Fitness and Evolvability of Personal Learning Environments (EFEPLE'11)

Abstract: Evolutionary or Darwinist theories are inherently controversial; applying them to explain and predict the trajectory of the development of Personal Learning Environments (PLE) is particularly challenging. PLE is still at its infancy stage, and a consensual definition is still lacking. Amongst others, the task of defining fitness models for predicting the rise and demise of specific widgets (which are commonly seen as the building blocks of PLE) and a specific configuration of PLE per se is daunting. The workshop is seen as the first step moving in the direction, though there are still many steps to be taken to achieve this seemingly insurmountable task. The initial step is seen as successful with intriguing ideas being conceived. Future work includes organizing a series of related workshops/seminars that involve participants with diverse backgrounds. Project proposals addressing the emergent topics are seen as a promising way to explore them in depth over a relatively long period of time. In the meantime several meetings amongst the workshop participants have been held to explore these possibilities.

Towards Ubiquitous Learning: 6th European Conference on Technology Anhanced Learning, EC-TEL 2011, Palermo, Italy, September 20-23, 2011, Proceedings ... / Programming and Software Engineering)

Abstract: This book constitutes the refereed proceedings of the 6th European Conference on Technology Enhanced Learning, EC-TEL 2011, held in Palermo, Italy, in September 2010. The 30 revised full papers presented were carefully reviewed and selected from 158 submissions. The book also includes 12 short papers, 8 poster papers, and 2 invited paper. There are many interesting papers on topics such as web 2.0 and social media, recommender systems, learning analytics, collaborative learning, interoperability of tools, etc.

Collision-Free Intersection Crossing of Mobile Robots Using Decentralized Navigation Functions on Predefined Paths

Abstract: This paper deals with the coordination of a group of mobile robots at an intersection. It focusses on decentralized navigation functions (DNFs) to achieve efficient traffic control. The main challenge is to define virtual potentials, which are used by decentralized navigation functions, such that traffic is both fluent and safe, while taking into account real-world limitations like acceleration, braking and speed limits. Our method consists in defining the navigation function with respect to the desired acceleration profile and is accompanied by a set of visibility conditions that increase the capacity of the intersection in terms of vehicle throughput. Priority conditions have been used to both avoid blockades of robots and to save energy by assigning higher priorities to robots with higher inertias.

Contextual Factors in the Adoption of Social Software: a Case Study

Abstract: Over the past decade, social computing has emerged immensely as a phenomenon among distributed communities. The benefits of social systems depend on a large part on the existence of an active user community who use it continuously to deploy and share information. However, while certain systems have enjoyed tremendous success (Facebook, twitter), others have experienced modest adoption at best. It is not clear what factors contribute to the rise and fall of these systems. This paper is a report on our experience with the deployment of a social software tool and our attempts to identify the major barriers to its adoption. We first introduce the system, Gleanr [6], and describe our research methodology. Based on our findings, we propose a set of contextual factors for successful adoption of such tools. While small-scale, our study might provide some insight on how to design social software systems with better chances of wide adoption.

A framework for usable end-user privacy control in social software systems

Abstract: Recent studies have shown that many users struggle to properly manage selective sharing of the diverse information artefacts they deposit in social software tools. Most tools define privacy based on the ‘network of friends’ model, in which all ‘friends’ are created equal and all relationships are reciprocal. This model fails to support the privacy expectations that non-technical users bring from their real-life experiences, such as enabling different degrees of intimacy within one’s network and providing flexible, natural means of managing the volatile social relationships that social software systems confront. Furthermore, the model suffers from lack of empirical grounding and systematic evaluation. This paper presents a framework for building privacy management mechanisms for social software systems that is intuitive and easy to use for the average, non-technical user population of these systems. The framework is based on a grounded theory study of users’ information sharing behaviour in a social software tool. Results inform the design of OpnTag, a social software prototype that facilitates personal and social information management and sharing. Preliminary empirical data suggest that our proposed privacy framework is flexible enough to meet users’ varying information sharing needs in different contexts while maintaining adequate support for usability.