Flexible organic–inorganic hybrid layer encapsulation for organic opto-electronic devices

In this work we produce and study the flexible organic–inorganic hybrid moisture barrier layers for the protection of air sensitive organic opto-electronic devices. The inorganic amorphous silicon nitride layer (SiNx:H) and the organic PMMA [poly (methyl methacrylate)] layer are deposited alternatingly by using hot wire chemical vapor deposition (HW-CVD) and spin-coating techniques, respectively. The effect of organic–inorganic hybrid interfaces is analyzed for increasing number of interfaces. We produce highly transparent (∼80% in the visible region) hybrid structures. The morphological properties are analysed providing a good basis for understanding the variation of the water vapor transmission rate (WVTR) values. A minimum WVTR of 4.5 × 10−5g/m2day is reported at the ambient atmospheric conditions for 7 organic/inorganic interfaces. The hybrid barriers show superb mechanical flexibility which confirms their high potential for flexible applications.

Optical properties of zirconium oxynitride films: the effect of composition, electronic and crystalline structures

tThis work is devoted to the investigation of zirconium oxynitride (ZrOxNy) films with varied opticalresponses prompted by the variations in their compositional and structural properties. The films wereprepared by dc reactive magnetron sputtering of Zr, using Ar and a reactive gas mixture of N2+ O2(17:3).The colour of the films changed from metallic-like, very bright yellow-pale and golden yellow, for low gasflows to red-brownish for intermediate gas flows. Associated to this colour change there was a significantdecrease of brightness. With further increase of the reactive gas flow, the colour of the samples changedfrom red-brownish to dark blue or even to interference colourations. The variations in composition dis-closed the existence of four different zones, which were found to be closely related with the variationsin the crystalline structure. XRD analysis revealed the change from a B1 NaCl face-centred cubic zirco-nium nitride-type phase for films prepared with low reactive gas flows, towards a poorly crystallizedover-stoichiometric nitride phase, which may be similar to that of Zr3N4with some probable oxygeninclusions within nitrogen positions, for films prepared with intermediate reactive gas flows. For highreactive gas flows, the films developed an oxynitride-type phase, similar to that of -Zr2ON2with someoxygen atoms occupying some of the nitrogen positions, evolving to a ZrO2monoclinic type structurewithin the zone where films were prepared with relatively high reactive gas flows. The analysis carriedout by reflected electron energy loss spectroscopy (REELS) revealed a continuous depopulation of thed-band and an opening of an energy gap between the valence band (2p) and the Fermi level close to 5 eV.The ZrN-based coatings (zone I and II) presented intrinsic colourations, with a decrease in brightness anda colour change from bright yellow to golden yellow, red brownish and dark blue. Associated to thesechanges, there was also a shift of the reflectivity minimum to lower energies, with the increase of thenon-metallic content. The samples lying in the two last zones (zone III, oxynitride and zone IV, oxide films)revealed a typical semi-transparent-optical behaviour showing interference-like colourations only dueto the complete depopulation of the d band at the Fermi level. The samples lying in these zones presentedalso an increase of the optical bandgap from 2 to 3.6 eV.

Modelação de governo electrónico para países emergentes: O caso de São Tomé e Príncipe

Tese de Doutoramento em Tecnologias e Sistemas de Informação

A celebração do contrato de seguro à distância

Dissertação de mestrado em Direito dos Contratos e da Empresa

Modelo de gestão integrada dos contratos públicos eletrónicos orientados ao valor público

Tese de Doutoramento em Tecnologias e Sistemas de Informação.

Electronic tongue: a versatile tool for mineral and fruit-flavored waters recognition

Natural mineral waters (still), effervescent natural mineral waters (sparkling) and aromatized waters with fruit-flavors (still or sparkling) are an emerging market. In this work, the capability of a potentiometric electronic tongue, comprised with lipid polymeric membranes, to quantitatively estimate routinely quality physicochemical parameters (pH and conductivity) as well as to qualitatively classify water samples according to the type of water was evaluated. The study showed that a linear discriminant model, based on 21 sensors selected by the simulated annealing algorithm, could correctly classify 100 % of the water samples (leave-one out cross-validation). This potential was further demonstrated by applying a repeated K-fold cross-validation (guaranteeing that at least 15 % of independent samples were only used for internal-validation) for which 96 % of correct classifications were attained. The satisfactory recognition performance of the E-tongue could be attributed to the pH, conductivity, sugars and organic acids contents of the studied waters, which turned out in significant differences of sweetness perception indexes and total acid flavor. Moreover, the E-tongue combined with multivariate linear regression models, based on sub-sets of sensors selected by the simulated annealing algorithm, could accurately estimate waters pH (25 sensors: R 2 equal to 0.99 and 0.97 for leave-one-out or repeated K-folds cross-validation) and conductivity (23 sensors: R 2 equal to 0.997 and 0.99 for leave-one-out or repeated K-folds cross-validation). So, the overall satisfactory results achieved, allow envisaging a potential future application of electronic tongue devices for bottled water analysis and classification.

How does banking industry influence economic growth in Latin American countries?

Mestrado em Finanças

Desarrollo sustentable de Productos y Servicios de Camélidos orientados al mercado en la región andina (DECAM). Sustainable Development Products and Services Marketed oriented in Andean Region

Este proyecto cuenta con el financiamiento del sistema INCO de la Unión Europea e incluye 5 contrapartes europeas, y Bolivia y Perú como contrapartes americanos. Consta de cuatro paquetes: producto, mercado, difusión y coordinación. En el primer paquete se desarrollan fundamentalmente los aspectos relacionados con la carne fresca y los productos cárnicos tanto tradicionales como nuevos a desarrollar. Se realizan faenas protocolizadas y espontáneas comparando animales con distintos tratamientos nutricionales de edades entre 19-21 meses. Se realizan análisis de calidad de carne y paneles de degustación. Los productos tradicionales como el charqui se evalúan en su forma tradicional y se implementan sistemas mejorados como desecadores solares. Los chacinados no son tradicionales en el altiplano por eso se realizan en La Pampa con la idea de transferir la tecnología desarrollada. La evaluación de calidad de la carne incluye técnicas de evaluación del animal en pié como la conservación morfológica y la ecografía para predecir calidad de res en el animal vivo. Estas observaciones se corroboran a la faena donde se realiza toda la batería de evaluaciones de calidad de la res.

Development of a semi-automatic self learning pattern recognition system for the control of electronic boards

This project was funded under the Applied Research Grants Scheme administered by Enterprise Ireland. The project was a partnership between Galway - Mayo Institute of Technology and an industrial company, Tyco/Mallinckrodt Galway. The project aimed to develop a semi - automatic, self - learning pattern recognition system capable of detecting defects on the printed circuits boards such as component vacancy, component misalignment, component orientation, component error, and component weld. The research was conducted in three directions: image acquisition, image filtering/recognition and software development. Image acquisition studied the process of forming and digitizing images and some fundamental aspects regarding the human visual perception. The importance of choosing the right camera and illumination system for a certain type of problem has been highlighted. Probably the most important step towards image recognition is image filtering, The filters are used to correct and enhance images in order to prepare them for recognition. Convolution, histogram equalisation, filters based on Boolean mathematics, noise reduction, edge detection, geometrical filters, cross-correlation filters and image compression are some examples of the filters that have been studied and successfully implemented in the software application. The software application developed during the research is customized in order to meet the requirements of the industrial partner. The application is able to analyze pictures, perform the filtering, build libraries, process images and generate log files. It incorporates most of the filters studied and together with the illumination system and the camera it provides a fully integrated framework able to analyze defects on printed circuit boards.

On privacy-awareness in social networking services

Magdeburg, Univ., Fak. für Informatik, Diss., 2011

Entwicklung eines Geschäftsmodells für verteilte ERP-Systeme auf Basis von Web Services

Magdeburg, Univ., Fak. für Informatik, Diss., 2012

Modeling usage of medical care services: the medical expenditure panel survey data, 1996-2000

We explore the determinants of usage of six different types of health care services, using the Medical Expenditure Panel Survey data, years 1996-2000. We apply a number of models for univariate count data, including semiparametric, semi-nonparametric and finite mixture models. We find that the complexity of the model that is required to fit the data well depends upon the way in which the data is pooled across sexes and over time, and upon the characteristics of the usage measure. Pooling across time and sexes is almost always favored, but when more heterogeneous data is pooled it is often the case that a more complex statistical model is required.

Entrepreneurship, management services and economic growth

We model the joint production of entrepreneurs and workers where the former provide both entrepreneurial (strategic) and managerial (coordination, motivation) services, and management services are shared with individual workers in an output maximizing way. The static equilibrium of the model determines the endogenous share of entrepreneurs in the economy in a given moment of time. The time dynamics of the solution implies that a given growth rate in quality of entrepreneurial services contributes to productivity growth proportionally to the share of entrepreneurs at the start of the period and improvement in quality of entrepreneurial services is convergence enhancing. Model predictions are tested with data from OECD countries in the period 1970-2002. We find that improvements in quality of entrepreneurial services over time explain up to 100% of observed average productivity growth in these countries.

Corporate governance in banking: the role of board of directors

We test hypotheses on the dual role of boards of directors for a sample of large international commercial banks. We find an inverted U shaped relation between bank performance and board size that justifies a large board and imposes an efficient limit to the board’s size; a positive relation between the proportion of non-executive directors and performance; and a proactive role in board meetings. Our results show that bank boards’ composition and functioning are related to directors’ incentives to monitor and advise management. All these relations hold after we control for bank business, institutional differences, size, market power in the banking industry, bank ownership and investors’ legal protection.

Use and users of electronic journals at Catalan universities: the results of a survey

Es presenten els resultats d’una enquesta sobre l’ús de revistes electròniques realitzada al professorat de les universitats que formen el Consorci de Biblioteques Universitàries de Catalunya (CBUC). Els resultats mostren un elevat grau de coneixement de la col·lecció de revistes electròniques entre el personal docent i investigador i una creixent preferència pel format electrònic en detriment de l’imprès. L’alt grau de coneixement i d’ús dels títols electrònics, i la preferència per aquest suport, comporten una elevada valoració de la col·lecció de revistes electròniques. Al mateix temps, la major part dels usuaris preveu un increment de l’ús dels títols electrònics durant els propers anys. Els resultats també confirmen la importància de la disciplina i de l’edat com a factors explicatius de l’ús de les revistes electròniques.