Integration of repositories in elearning systems

The wide acceptance of digital repositories today in the eLearning field raises several interoperability issues. In this paper we present the interoperability features of a service oriented repository of learning objects called crimsonHex. These features are compliant with the existing standards and we propose extensions to the IMS interoperability recommendation, adding new functions, formalizing message interchange and providing also a REST interface. To validate the proposed extensions and its implementation in crimsonHex we developed a repository plugin for Moodle 2.0 that is expected to be included in the next release of this popular learning management system.

Project of a bandgap voltage reference and a temperature sensor for "energy harvest" systems

Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e Computadores

Circuito de leitura digital para MEMS capacitivos

Dissertação de mestrado integrado em Engenharia Eletrónica Industrial e Computadores

Luto digital: plataformas para a gestão da herança digital

Dissertação de mestrado integrado em Engenharia e Gestão de Sistemas de Informação

Diseño de sistemas de comunicaciones de alta velocidad. Design of high-speed communication systems.

El crecimiento exponencial del tráfico de datos es uno de los mayores desafíos que enfrentan actualmente los sistemas de comunicaciones, debiendo los mismos ser capaces de soportar velocidades de procesamiento de datos cada vez mas altas. En particular, el consumo de potencia se ha transformado en uno de los parámetros de diseño más críticos, generando la necesidad de investigar el uso de nuevas arquitecturas y algoritmos para el procesamiento digital de la información. Por otro lado, el análisis y evaluación de nuevas técnicas de procesamiento presenta dificultades dadas las altas velocidades a las que deben operar, resultando frecuentemente ineficiente el uso de la simulación basada en software como método. En este contexto, el uso de electrónica programable ofrece una oportunidad a bajo costo donde no solo se evaluan nuevas técnicas de diseño de alta velocidad sino también se valida su implementación en desarrollos tecnológicos. El presente proyecto tiene como objetivo principal el estudio y desarrollo de nuevas arquitecturas y algoritmos en electrónica programable para el procesamiento de datos a alta velocidad. El método a utilizar será la programación en dispositivos FPGA (Field-Programmable Gate Array) que ofrecen una buena relación costo-beneficio y gran flexibilidad para integrarse con otros dispositivos de comunicaciones. Para la etapas de diseño, simulación y programación se utilizaran herramientas CAD (Computer-Aided Design) orientadas a sistemas electrónicos digitales. El proyecto beneficiara a estudiantes de grado y postgrado de carreras afines a la informática y las telecomunicaciones, contribuyendo al desarrollo de proyectos finales y tesis doctorales. Los resultados del proyecto serán publicados en conferencias y/o revistas nacionales e internacionales y divulgados a través de charlas de difusión y/o encuentros. El proyecto se enmarca dentro de un área de gran importancia para la Provincia de Córdoba, como lo es la informática y las telecomunicaciones, y promete generar conocimiento de gran valor agregado que pueda ser transferido a empresas tecnológicas de la Provincia de Córdoba a través de consultorias o desarrollos de productos.

Copper filtration in pediatric digital X-ray imaging: its impact on image quality and dose.

The effect of copper (Cu) filtration on image quality and dose in different digital X-ray systems was investigated. Two computed radiography systems and one digital radiography detector were used. Three different polymethylmethacrylate blocks simulated the pediatric body. The effect of Cu filters of 0.1, 0.2, and 0.3 mm thickness on the entrance surface dose (ESD) and the corresponding effective doses (EDs) were measured at tube voltages of 60, 66, and 73 kV. Image quality was evaluated in a contrast-detail phantom with an automated analyzer software. Cu filters of 0.1, 0.2, and 0.3 mm thickness decreased the ESD by 25-32%, 32-39%, and 40-44%, respectively, the ranges depending on the respective tube voltages. There was no consistent decline in image quality due to increasing Cu filtration. The estimated ED of anterior-posterior (AP) chest projections was reduced by up to 23%. No relevant reduction in the ED was noted in AP radiographs of the abdomen and pelvis or in posterior-anterior radiographs of the chest. Cu filtration reduces the ESD, but generally does not reduce the effective dose. Cu filters can help protect radiosensitive superficial organs, such as the mammary glands in AP chest projections.

EORTC Radiation Oncology Group quality assurance platform: establishment of a digital central review facility.

OBJECTIVE: Quality assurance (QA) in clinical trials is essential to ensure treatment is safely and effectively delivered. As QA requirements have increased in complexity in parallel with evolution of radiation therapy (RT) delivery, a need to facilitate digital data exchange emerged. Our objective is to present the platform developed for the integration and standardization of QART activities across all EORTC trials involving RT. METHODS: The following essential requirements were identified: secure and easy access without on-site software installation; integration within the existing EORTC clinical remote data capture system; and the ability to both customize the platform to specific studies and adapt to future needs. After retrospective testing within several clinical trials, the platform was introduced in phases to participating sites and QART study reviewers. RESULTS: The resulting QA platform, integrating RT analysis software installed at EORTC Headquarters, permits timely, secure, and fully digital central DICOM-RT based data review. Participating sites submit data through a standard secure upload webpage. Supplemental information is submitted in parallel through web-based forms. An internal quality check by the QART office verifies data consistency, formatting, and anonymization. QART reviewers have remote access through a terminal server. Reviewers evaluate submissions for protocol compliance through an online evaluation matrix. Comments are collected by the coordinating centre and institutions are informed of the results. CONCLUSIONS: This web-based central review platform facilitates rapid, extensive, and prospective QART review. This reduces the risk that trial outcomes are compromised through inadequate radiotherapy and facilitates correlation of results with clinical outcomes.

ARCHITECTING USER-CENTRIC PRIVACY-AS-A-SET-OF-SERVICES: DIGITAL IDENTITY RELATED PRIVACY FRAMEWORK

AbstractDigitalization gives to the Internet the power by allowing several virtual representations of reality, including that of identity. We leave an increasingly digital footprint in cyberspace and this situation puts our identity at high risks. Privacy is a right and fundamental social value that could play a key role as a medium to secure digital identities. Identity functionality is increasingly delivered as sets of services, rather than monolithic applications. So, an identity layer in which identity and privacy management services are loosely coupled, publicly hosted and available to on-demand calls could be more realistic and an acceptable situation. Identity and privacy should be interoperable and distributed through the adoption of service-orientation and implementation based on open standards (technical interoperability). Ihe objective of this project is to provide a way to implement interoperable user-centric digital identity-related privacy to respond to the need of distributed nature of federated identity systems. It is recognized that technical initiatives, emerging standards and protocols are not enough to guarantee resolution for the concerns surrounding a multi-facets and complex issue of identity and privacy. For this reason they should be apprehended within a global perspective through an integrated and a multidisciplinary approach. The approach dictates that privacy law, policies, regulations and technologies are to be crafted together from the start, rather than attaching it to digital identity after the fact. Thus, we draw Digital Identity-Related Privacy (DigldeRP) requirements from global, domestic and business-specific privacy policies. The requirements take shape of business interoperability. We suggest a layered implementation framework (DigldeRP framework) in accordance to model-driven architecture (MDA) approach that would help organizations' security team to turn business interoperability into technical interoperability in the form of a set of services that could accommodate Service-Oriented Architecture (SOA): Privacy-as-a-set-of- services (PaaSS) system. DigldeRP Framework will serve as a basis for vital understanding between business management and technical managers on digital identity related privacy initiatives. The layered DigldeRP framework presents five practical layers as an ordered sequence as a basis of DigldeRP project roadmap, however, in practice, there is an iterative process to assure that each layer supports effectively and enforces requirements of the adjacent ones. Each layer is composed by a set of blocks, which determine a roadmap that security team could follow to successfully implement PaaSS. Several blocks' descriptions are based on OMG SoaML modeling language and BPMN processes description. We identified, designed and implemented seven services that form PaaSS and described their consumption. PaaSS Java QEE project), WSDL, and XSD codes are given and explained.

Implantación de una Plataforma GNU/Linux en la gestión del hogar digital focalizada a la domótica,multimedia-ocio y las TICs.

In the near future, access to data and home automation systems in the home supported by the implementation of GNU-Linux operating systems in our homes, a reality of the first order for the implementation of real homes and automated digital awarding a cost reduction by the intensive use of the resources provided directly by the Open Software Community. The future possibilities seem almost endless: telecommuting, centralized household accounts, software distributed online training for young people in the house, multimedia at all levels, design and artistic creation (particularly through electronic digital displays are spreading rapidly in our homes), targeted towards home automation automated digital, integrated control of home security, digital entertainment ... and with free applications at no additional cost that can be easily downloaded from the usual repositories, ensuring the online update of these tools. In short, new ways of understanding in the home automation, telecommuting and digital entertainment within the broader framework of our Information Society.

Digital beamforming and moving target indication for future spaceborne synthetic aperture radar

During the last decade the interest on space-borne Synthetic Aperture Radars (SAR) for remote sensing applications has grown as testified by the number of recent and forthcoming missions as TerraSAR-X, RADARSAT-2, COSMO-kyMed, TanDEM-X and the Spanish SEOSAR/PAZ. In this sense, this thesis proposes to study and analyze the performance of the state-of-the-Art space-borne SAR systems, with modes able to provide Moving Target Indication capabilities (MTI), i.e. moving object detection and estimation. The research will focus on the MTI processing techniques as well as the architecture and/ or configuration of the SAR instrument, setting the limitations of the current systems with MTI capabilities, and proposing efficient solutions for the future missions. Two European projects, to which the Universitat Politècnica de Catalunya provides support, are an excellent framework for the research activities suggested in this thesis. NEWA project proposes a potential European space-borne radar system with MTI capabilities in order to fulfill the upcoming European security policies. This thesis will critically review the state-of-the-Art MTI processing techniques as well as the readiness and maturity level of the developed capabilities. For each one of the techniques a performance analysis will be carried out based on the available technologies, deriving a roadmap and identifying the different technological gaps. In line with this study a simulator tool will be developed in order to validate and evaluate different MTI techniques in the basis of a flexible space-borne radar configuration. The calibration of a SAR system is mandatory for the accurate formation of the SAR images and turns to be critical in the advanced operation modes as MTI. In this sense, the SEOSAR/PAZ project proposes the study and estimation of the radiometric budget. This thesis will also focus on an exhaustive analysis of the radiometric budget considering the current calibration concepts and their possible limitations. In the framework of this project a key point will be the study of the Dual Receive Antenna (DRA) mode, which provides MTI capabilities to the mission. An additional aspect under study is the applicability of the Digital Beamforming on multichannel and/or multistatic radar platforms, which conform potential solutions for the NEWA project with the aim to fully exploit its capability jointly with MTI techniques.

New delay-dependent stability criteria for uncertain neutral systems with mixed time-varying delays and nonlinear perturbations

The problem of stability analysis for a class of neutral systems with mixed time-varying neutral, discrete and distributed delays and nonlinear parameter perturbations is addressed. By introducing a novel Lyapunov-Krasovskii functional and combining the descriptor model transformation, the Leibniz-Newton formula, some free-weighting matrices, and a suitable change of variables, new sufficient conditions are established for the stability of the considered system, which are neutral-delay-dependent, discrete-delay-range dependent, and distributeddelay-dependent. The conditions are presented in terms of linear matrix inequalities (LMIs) and can be efficiently solved using convex programming techniques. Two numerical examples are given to illustrate the efficiency of the proposed method

Disseny i implementació d’un quiosc digital per a dispositius iOS

Hermes Comunicacions és el primer grup de comunicació escrita en català, quecompta amb 54.000 exemplars cada dia al carrer i prop de 600.000 lectors ainternet. És la responsable de les publicacions: El Punt Avui (edicions Nacionali Comarques Gironines), Presència, L’Econòmic, Sortim, Catalonia Today i El 9Esportiu.Actualment, es disposa de tres vies per difondre les diferents publicacions: paper, web i El quiosc (web d’accés a subscriptors). Aquest projecte pretén desenvolupar l’aplicació i entorn necessaris per lacreació d’una quarta via de difusió dels diferents productes, facilitant-ne lavisualització mitjançant dispositius mòbils. Concretament ens centrarem en elsdispositius mòbils d’Apple basats en el sistema operatiu iOS.Degut a que ens trobem davant d’un nou entorn per als desenvolupadors i peral client, preveiem que aniran sorgint canvis durant el transcurs del projecte.Per tant decidim utilitzar una metodologia flexible als canvis de requeriments.Les metodologies àgils són les que millor s’ajusten al desenvolupament que esvol fer. Dins el conjunt de metodologies àgils, hem escollit Scrum. Tot i que és unametodologia pensada per a treball en equip, l’adaptem al nostre cas

Modeling of hybrid systems by piecewise decomposition

Piecewise linear models systems arise as mathematical models of systems in many practical applications, often from linearization for nonlinear systems. There are two main approaches of dealing with these systems according to their continuous or discrete-time aspects. We propose an approach which is based on the state transformation, more particularly the partition of the phase portrait in different regions where each subregion is modeled as a two-dimensional linear time invariant system. Then the Takagi-Sugeno model, which is a combination of local model is calculated. The simulation results show that the Alpha partition is well-suited for dealing with such a system

An LMI approach to H∞ synchronization of second-order neutral master-slave systems

The H∞ synchronization problem of the master and slave structure of a second-order neutral master-slave systems with time-varying delays is presented in this paper. Delay-dependent sufficient conditions for the design of a delayed output-feedback control are given by Lyapunov-Krasovskii method in terms of a linear matrix inequality (LMI). A controller, which guarantees H∞ synchronization of the master and slave structure using some free weighting matrices, is then developed. A numerical example has been given to show the effectiveness of the method

Enabling mobile access to digital libraries in digital divide contexts

Digital libraries (DL) have had a tremendous impact on improving the accessibility of scientific and academic publications. In developing countries, they seem to be the great hope, due to the serious existing problems with the traditional publishing and distribution mechanisms and to the potential they have on enabling access to a great panoply of publications. Moreover, accessing digital libraries over mobile devices has the potential of reaching a broader community of users and on helping to bridge the digital divide, since there are very reduced computer and Internet penetration rates in these countries, along with a higher mobile phone usage. For developed countries, accessing digital libraries on the go might also bring important added value. This paper features an analysis of the major issues related to making digital libraries accessible over mobile devices. A specific study on the possibility of using mobile digital libraries in a developing country context is also presented along with a proposal for making DSpace based digital libraries accessible over mobile phones.