Nanoestructuras de óxidos de estaño y titanio y sus composites basados en PEDOT:PSS : aplicaciones en células solares, termoeléctricos y sensores de gases

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Ciencias Físicas, Departamento de Física de Materiales, leída el 26-11-2021Wide band gap semiconductors based on inorganic materials such SnO, SnO2or TiO2 present excellent chemical properties which make them suitable for different energy-related application such as Li-ion batteries, gas sensing or solar cells. Their involvement in such applications could be improved with controlled fabrication methods as well as by controlled doping to modify their morphology, sizeor optoelectronic properties. Besides, organic materials have attracted growing interest due their outstanding unique properties as flexibility, malleability or low cost. PEDOT:PSS is an organic polymer which possesses not only p-type conductivity but also transparency to visible light, valuable properties for energy applications...Los semiconductores de band gap ancho basados en materiales inorgánicos como el SnO, el SnO2 o el TiO2 presentan excelentes propiedades físicas y químicas que los hacen adecuados para diferentes aplicaciones relacionadas con la energía, como las baterías de ion de litio, la detección de gases o las células solares. Su empleo en estas aplicaciones podría verse mejorado con métodos de fabricación controlados así como mediante la introducción de dopantes de manera controlada para modificar su morfología, tamaño o propiedades optoelectrónicas. Además, los materiales orgánicos han suscitado un interés creciente debido a sus excepcionales propiedades, como la flexibilidad, la maleabilidad o el bajo coste. El PEDOT:PSS es un polímero orgánico que posee no sólo conductividad de tipo p, sino también transparencia a la luz visible, propiedades valiosas para las aplicaciones energéticas...Fac. de Ciencias FísicasTRUEunpu

Three essays in corporate governance, accounting and law

This dissertation contains three essays related to the areas of corporate governance, accounting and law. Chapter 1 sets out to investigate the intersection of corporate governance and accounting, where we inspect the impact of a corporate governance institution (independent directors) on a measure of accounting quality (real earnings management). Moreover, Chapter 2 links with the previous chapter in that I inspect the impact of independent directors and their legal incentives on the decision whether to payout (dividends or repurchases) or to reinvest. Finally, Chapter 3 connects with the prior two in that it inspects how inside board members impact corporate performance and we derive some policy implications for regulators about inside director participation in outside boards.Programa de Doctorado en Empresa y Finanzas / Business and Finance por la Universidad Carlos III de MadridPresidente: Juan Pedro Gómez; Secretario: Beatriz Mariano; Vocal: Renee Adam

Protección de datos médicos e Internet

This report presents a discussion of the adventages electronic clinical data gives, not only to the medical staff (helping them to get more accurate data about their patients) but also to the patient (receiving a better medical care). Then we present a study of the current spanish and european laws that rule about protection of medical data. Finally we present the characteristics a distributed information system managing and storing medical data should have, and the security measures to be taken if such a system is connected to a public network such as Internet.Postprint (published version

Spatiotemporal Stacked Sequential Learning for Pedestrian Detection

Pedestrian classifiers decide which image windows contain a pedestrian. In practice, such classifiers provide a relatively high response at neighbor windows overlapping a pedestrian, while the responses around potential false positives are expected to be lower. An analogous reasoning applies for image sequences. If there is a pedestrian located within a frame, the same pedestrian is expected to appear close to the same location in neighbor frames. Therefore, such a location has chances of receiving high classification scores during several frames, while false positives are expected to be more spurious. In this paper we propose to exploit such correlations for improving the accuracy of base pedestrian classifiers. In particular, we propose to use two-stage classifiers which not only rely on the image descriptors required by the base classifiers but also on the response of such base classifiers in a given spatiotemporal neighborhood. More specifically, we train pedestrian classifiers using a stacked sequential learning (SSL) paradigm. We use a new pedestrian dataset we have acquired from a car to evaluate our proposal at different frame rates. We also test on a well known dataset: Caltech. The obtained results show that our SSL proposal boosts detection accuracy significantly with a minimal impact on the computational cost. Interestingly, SSL improves more the accuracy at the most dangerous situations, i.e. when a pedestrian is close to the camera.Comment: 8 pages, 5 figure, 1 tabl

A Generalized Regression Methodology for Bivariate Heteroscedastic Data

We present a methodology for reducing a straight line fitting regression problem to a Least Squares minimization one. This is accomplished through the definition of a measure on the data space that takes into account directional dependences of errors, and the use of polar descriptors for straight lines. This strategy improves the robustness by avoiding singularities and non-describable lines. The methodology is powerful enough to deal with non-normal bivariate heteroscedastic data error models, but can also supersede classical regression methods by making some particular assumptions. An implementation of the methodology for the normal bivariate case is developed and evaluated

Improved estimation of Weibull Parameters considering unreliability uncertainties

We propose a linear regression method for estimating Weibull parameters from life tests. The method uses stochastic models of the unreliability at each failure instant. As a result, a heteroscedastic regression problem arises that is solved by weighted least squares minimization. The main feature of our method is an innovative s-normalization of the failure data models, to obtain analytic expressions of centers and weights for the regression. The method has been Monte Carlo contrasted with Benard?s approximation, and Maximum Likelihood Estimation; and it has the highest global scores for its robustness, and performance

UCTx: a multi-agent system to assist a transplant coordination unit

We present a system called UCTx, designed to model and automate some of the tasks performed by a Transplant Coordination Unit (UCTx) inside a Hospital. The aim of this work is to show how a multi-agent approach allows us to describe and implement the model, and how UCTx is capable of dealing with another multi-agent (Carrel, an Agent Mediated Institution for the exchange of Human Tissues among Hospitals for Transplantation) in order to meet its own goals, acting as the representative of the hospital in the negotiation. As an example we introduce the use of this Agency in the case of Cornea Transplantation.Postprint (published version

Assessing the Influence of Strategic Resources on the Quality of Life in Spanish Cities

[Abstract] Quality of life (QoL) is both a main concern of good local governance and an indicator of city performance. A key question to answer is that of what resources have the potential to enhance city performance, thus providing added value to stakeholders. By adopting a resource-based view (RBV), this paper explores the relationships between a group of strategic resources (e-government, transparency, and reputation) and QoL in a sample of 78 Spanish municipalities. Our study makes a contribution by providing an original design of a set of relations among our own selected resources and between them and quality of life. In order to test those relations, we define and create four constructs by using four different data sources and structural equation modeling (SEM). The results show a positive influence of resources on QoL, which is supported by a number of positive direct and indirect interactions among them. This means that municipalities with better strategic resources in local governments exhibit a higher level of quality of life

Waveform-independent frame-timing acquisition for UWB signals

In this paper, the problem of frame-level symbol timing acquisition for UWB signals is addressed. The main goal is the derivation of a frame-level timing estimator which does not require any prior knowledge of neither the transmitted symbols nor the received template waveform. The independence with respect to the received waveform is of special interest in UWB communication systems, where a fast and accurate estimation of the end-to-end channel response is a challenging and computationally demanding task. The proposed estimator is derived under the unconditional maximum likelihood criterion, and because of the low power of UWB signals, the low-SNR assumption is adopted. As a result, an optimal frame-level timing estimator is derived which outperforms existing acquisition methods in low-SNR scenarios.Peer Reviewe