Analytical efficiency evaluation of a network mobility management protocol for Intelligent Transportation Systems

One of the major concerns in an Intelligent Transportation System (ITS) scenario, such as that which may be found on a long-distance train service, is the provision of efficient communication services, satisfying users' expectations, and fulfilling even highly demanding application requirements, such as safety-oriented services. In an ITS scenario, it is common to have a significant amount of onboard devices that comprise a cluster of nodes (a mobile network) that demand connectivity to the outside networks. This demand has to be satisfied without service disruption. Consequently, the mobility of the mobile network has to be managed. Due to the nature of mobile networks, efficient and lightweight protocols are desired in the ITS context to ensure adequate service performance. However, the security is also a key factor in this scenario. Since the management of the mobility is essential for providing communications, the protocol for managing this mobility has to be protected. Furthermore, there are safety-oriented services in this scenario, so user application data should also be protected. Nevertheless, providing security is expensive in terms of efficiency. Based on this considerations, we have developed a solution for managing the network mobility for ITS scenarios: the NeMHIP protocol. This approach provides a secure management of network mobility in an efficient manner. In this article, we present this protocol and the strategy developed to maintain its security and efficiency in satisfactory levels. We also present the developed analytical models to analyze quantitatively the efficiency of the protocol. More specifically, we have developed models for assessing it in terms of signaling cost, which demonstrates that NeMHIP generates up to 73.47% less signaling compared to other relevant approaches. Therefore, the results obtained demonstrate that NeMHIP is the most efficient and secure solution for providing communications in mobile network scenarios such as in an ITS context.

Decarbonising urban transportation

18 p.

The Spanish Pension System: Overview and Long-Term Projections

In the middle of the so-called pension crisis, the ageing of population and the sharp decrease in affiliations to Social Security are threatening the well-functioning of the Spanish public pension system. The purpose of this paper is to present the main challenges to be faced by the Spanish pension system, as well as to shed light on the main determinants that will condition the evolution of pension expenditure over GDP along the following decades. This quantitative analysis, which considers the 2011 and 2013 pension reforms, uses the latest data on the Spanish demographic, labor market and institutional factors in order to project the evolution of the system from the expenditure side up to 2060. For the purpose of analyzing the dynamics and the underlying drivers of pension expenditure, the so-called aggregate accounting approach will be utilized. The alternative scenarios proposed allow for exploring the robustness of the results within the baseline scenario, which constitutes the reference point of projections in the exercise. The analysis concludes that, by the end of the projected period, Spain will count on a similar public pension expenditure ratio as the current one.

El sistema sanitario público, sus servicios y sus responsables: creación y pilotaje de su imagen

[ES] Actualmente, el sistema sanitario público en España se encuentra en una etapa de modernización, marcadamente orientada hacia los destinatarios de sus servicios, es decir, el conjunto de los ciudadanos. Entre el amplio conjunto de acciones que se están implementando, destaca la implantación de nuevas fórmulas organizativas, la instalación de tecnologías avanzadas en información y comunicación, la gestión estratágica de los recursos humanos o la aplicación de técnicas de calidad total.

Camino a la jubilación: alquiler versus compra de vivienda

Las previsiones del número de personas mayores en España para el año 2050 se han disparado. Un aumento de la población mayor que supondrá grandes dificultades para un sistema público de pensiones cuya viabilidad está en duda. España es un país en el que la cultura del ahorro a través de la vivienda en propiedad está muy arraigada. Sin embargo, en la actualidad existe un auge de las personas que optan por el alquiler como forma de residencia. Por ello, durante este trabajo se analiza la vida de una persona que optará bien por la compra de una vivienda o bien por el alquiler de una vivienda para complementar su futura pensión pública. Mediante la compra de vivienda, y una vez amortizado el préstamo hipotecario que deberá soportar, se le presentaran los productos denominados vivienda pensión e hipoteca inversa para financiar las posibles necesidades que puedan surgir en su jubilación. Por otro lado, el arrendatario optara por un producto de ahorro a largo plazo, cuya rentabilidad variara a lo largo del tiempo en función de su aversión al riesgo, de manera que llegado el momento de la jubilación disponga de un capital.

Implementation of a nursing competency assessment system in public hospitals

Numerous problems are frequently observed when nursing competency assessment systems (NCAS) are implemented. How to effectively implement a nursing competency assessment system, according to academic and practical contributions, is poorly reported in the literature. The purpose of this paper is to present a set of recommendations for public hospitals and nursing management in order to facilitate the implementation of a NCAS. To achieve this objective we have revised the existing literature and conducted a Delphi study with nursing managers and human resource managers of the public hospitals of the Basque Health Service. The results are that the implementation of a NCAS requires a well-planned strategy that managers must consider before implementing any NCAS. This strategy must include, at minimum, the following aspects: communication, training, leadership, and content where the NCAS is concerned. The context of the organisations and the cultural dimensions may also influence the results of the application of the system.

Learning Multirobot Hose Transportation and Deployment by Distributed Round-Robin Q-Learning

Multi-Agent Reinforcement Learning (MARL) algorithms face two main difficulties: the curse of dimensionality, and environment non-stationarity due to the independent learning processes carried out by the agents concurrently. In this paper we formalize and prove the convergence of a Distributed Round Robin Q-learning (D-RR-QL) algorithm for cooperative systems. The computational complexity of this algorithm increases linearly with the number of agents. Moreover, it eliminates environment non sta tionarity by carrying a round-robin scheduling of the action selection and execution. That this learning scheme allows the implementation of Modular State-Action Vetoes (MSAV) in cooperative multi-agent systems, which speeds up learning convergence in over-constrained systems by vetoing state-action pairs which lead to undesired termination states (UTS) in the relevant state-action subspace. Each agent's local state-action value function learning is an independent process, including the MSAV policies. Coordination of locally optimal policies to obtain the global optimal joint policy is achieved by a greedy selection procedure using message passing. We show that D-RR-QL improves over state-of-the-art approaches, such as Distributed Q-Learning, Team Q-Learning and Coordinated Reinforcement Learning in a paradigmatic Linked Multi-Component Robotic System (L-MCRS) control problem: the hose transportation task. L-MCRS are over-constrained systems with many UTS induced by the interaction of the passive linking element and the active mobile robots.