Cookies Policy
The website need some cookies and similar means to function. If you permit us, we will use those means to collect data on your visits for aggregated statistics to improve our service. Find out More
Accept Reject
  • Menu
Publications

Publications by CRACS

2009

CrimsonHex: A Service Oriented Repository of Specialised Learning Objects

Authors
Leal, JP; Qleiros, R;

Publication
ENTERPRISE INFORMATION SYSTEMS-BK

Abstract
The corner stone of the interoperability of eLearning systems is the standard definition of learning objects. Nevertheless, for some domains this standard is insufficient to fully describe all the assets, especially when they are used as input for other eLearning services. On the other hand, a standard definition of learning objects in not enough to ensure interoperability among eLearning systems; they must also use a standard API to exchange learning objects. This paper presents the design and implementation of a service oriented repository of learning objects called crimsonHex. This repository is fully compliant with the existing interoperability standards and supports new definitions of learning objects for specialized domains. We illustrate this feature with the definition of programming problems as learning objects and its validation by the repository. This repository is also prepared to store usage data on learning objects to tailor the presentation order and adapt it to learner profiles.

2009

Defining programming problems as learning objects

Authors
Leal, JP; Queiros, R;

Publication
World Academy of Science, Engineering and Technology

Abstract
Standards for learning objects focus primarily on content presentation. They were already extended to support automatic evaluation but it is limited to exercises with a predefined set of answers. The existing standards lack the metadata required by specialized evaluators to handle types of exercises with an indefinite set of solutions. To address this issue existing learning object standards were extended to the particular requirements of a specialized domain. A definition of programming problems as learning objects, compatible both with Learning Management Systems and with systems performing automatic evaluation of programs, is presented in this paper. The proposed definition includes metadata that cannot be conveniently represented using existing standards, such as: the type of automatic evaluation; the requirements of the evaluation engine; and the roles of different assets - tests cases, program solutions, etc. The EduJudge project and its main services are also presented as a case study on the use of the proposed definition of programming problems as learning objects.

2009

Designing a user interface for repositories of learning objects

Authors
Leal, JP; Queiros, R;

Publication
Proceedings of the IADIS International Conference e-Learning 2009, Part of the IADIS Multi Conference on Computer Science and Information Systems, MCCSIS 2009

Abstract
This paper presents the design of a user interface for repositories of learning objects. It integrates several tasks, such as submission, browse, search, and comment/review of learning objects, on a single screen layout. This design is being implemented on the web front-end of crimsonHex, a repository of specialized learning objects, developed as part of the EduJudge, a European project that aims to bring automatic evaluation of programming problems to e-Learning systems. © 2009 IADIS.

2009

An architecture for the rapid development of XML-based web applications

Authors
Leal, JP; Gonalves, JB;

Publication
ICEIS 2009 - 11th International Conference on Enterprise Information Systems, Proceedings

Abstract
Our research goal is the generation of working web applications from high level specifications. Based on our experience in using XML transformations for that purpose, we applied this approach to the rapid development of database management applications. The result is an architecture that defines of a web application as a set of XML transformations, and generates these transformations using second order transformations from a database schema. We used the Model-View-Controller architectural pattern to assign different roles to transformations, and defined a pipeline of transformations to process an HTTP request. The definition of these transformations is based on a correspondence between data-oriented XML Schema definitions and the Entity-Relationship model. Using this correspondence we were able produce transformations that implement database operations, forms interfaces generators and application controllers, as well as the second order transformations that produce all of them. This paper includes also a description of a RAD system following this architecture that allowed us to perform a critical evaluation of this proposal.

2009

Programming Wireless Sensor Networks

Authors
Lopes, LMB; Martins, F; Barros, J;

Publication
Middleware for Network Eccentric and Mobile Applications

Abstract
Sensor networks can be viewed as a collection of tiny, low-cost devices programmed to sense the physical world and that communicate over radio links [12]. The devices are commonly called motes or smart dust [676], in allusion to their computational and sensing capabilities, as well as their increasingly small size. © 2009 Springer Berlin Heidelberg.

2009

Towards the Safe Programming of Wireless Sensor Networks

Authors
Martins, F; Lopes, LMB; Barros, J;

Publication
Proceedings Second International Workshop on Programming Language Approaches to Concurrency and Communication-cEntric Software, PLACES 2009, York, UK, 22nd March 2009.

Abstract

  • 160
  • 201