Blind classification of e-scooter trips according to their relationship with public transport

E-scooter services have multiplied worldwide as a form of urban transport. Their use has grown so quickly that policymakers and researchers still need to understand their interrelation with other transport modes. At present, e-scooter services are primarily seen as a first-and-last-mile solution for public transport. However, we demonstrate that 50% of e-scooter trips are either substituting it or covering areas with little public transportation infrastructure. To this end, we have developed a novel data-driven methodology that autonomously classifies e-scooter trips according to their relation to public transit. Instead of predefined design criteria, the blind nature of our approach extracts the city’s intrinsic parameters from real data. We applied this methodology to Rome (Italy), and our findings reveal that e-scooters provide specific mobility solutions in areas with particular needs. Thus, we believe that the proposed methodology will contribute to the understanding of e-scooter services as part of shared urban mobility

Análisis del grado de conocimiento e interés de los profesionales sanitarios de nefrología sobre la planificación anticipada de la asistencia sanitaria

a tener que tomar decisiones continuamente. En este proceso los profesionales sanitarios no suelen preguntarles cómo querrían planificar el final de sus días. En una sociedad donde la “no limitación al esfuerzo terapéutico” parece una constante en nuestra práctica, el reflexionar sobre nuestros propios límites podría ayudarnos en la atención a los pacientes. Objetivo: Conocer el grado de conocimiento e interés por la Planificación Anticipada de la Asistencia Sanitaria (PAAS) en profesionales que atienden a pacientes con Enfermedad Renal Crónica. Material y Método: Estudio observacional descriptivo transversal mediante cuestionario autoadministrado a sanitarios participantes voluntarios a nivel nacional. El cuestionario incluía 22 preguntas sobre conocimiento e interés sobre la planificación anticipada de la asistencia sanitaria. Resultados: Respondieron 422 profesionales: 53,3% médicos; 45,0% enfermeras y 1,4% técnicos en cuidados auxiliares de enfermería. El 79,9% no conocen cuantos pacientes tienen registrado el Documento de Voluntades Anticipadas. El 63,5% han oído hablar de la Planificación Anticipada de la Asistencia Sanitaria. Un 28,7% conoce la diferencia entre la Planificación Anticipada de la Asistencia Sanitaria y el Documento de Voluntades Anticipadas. Un 96,2% afirma que tener esta información ayudaría a los pacientes a que estuvieran mejor atendidos en sus últimos días. El 97,6% de los profesionales piensan que está en nuestra mano hacer algo más, a un 94,5% les gustaría recibir formación. Conclusión: Existe falta de conocimiento y un gran interés por los profesionales sanitarios sobre la Planificación Anticipada de la Asistencia Sanitaria

Exploiting Semantic Technologies in Smart Environments and Grids: Emerging Roles and Case Studies

Semantic technologies are currently spreading across several application domains as a reliable and consistent mean to address challenges related to organization, manipulation, visualization and exchange of data and knowledge. Different roles are actually played by these techniques depending on the application domain, on the timing constraints, on the distributed nature of applications, and so on. This paper provides an overview of the roles played by semantic technologies in the domain of smart grids and smart environments, with a particular focus on changes brought by such technologies in the adopted architectures, programming techniques and tools. Motivations driving the adoption of semantics in these different, but strictly intertwined, fields are introduced using a strong application-driven perspective. Two real-world case studies in smart grids and smart environments are presented to exemplify the roles covered by such technologies and the changes they fostered in software engineering processes. Learned lessons are then distilled and future adoption scenarios discussed

Hierarchical Agglomerative Clustering of Bicycle Sharing Stations Based on Ultra-Light Edge Computing

Bicycle sharing systems (BSSs) have established a new shared-economy mobility model. After a rapid growth they are evolving into a fully-functional mobile sensor platform for cities. The viability of BSSs is floored by their operational costs, mainly due to rebalancing operations. Rebalancing implies transporting bicycles to and from docking stations in order to guarantee the service. Rebalancing performs clustering to group docking stations by behaviour and proximity. In this paper we propose a Hierarchical Agglomerative Clustering based on an Ultra-Light Edge Computing Algorithm (HAC-ULECA). We eliminate the proximity and let Hierarchical Agglomerative Clustering (HAC) focus on behaviour. Behaviour is represented by ULECA as an activity profile based on the net flow of arrivals and departures in a docking station. This drastically reduces the computing requirements which allows ULECA to run as an edge computing functionality embedded into the physical layer of the Internet of Shared Bikes (IoSB) architecture. We have applied HAC-ULECA to real data from BiciMAD, the public BSS in Madrid (Spain). Our results, presented as dendograms, graphs, geographical maps, and colour maps, show that HAC-ULECA is capable of separating behaviour profiles related to business and residential areas and extracting meaningful spatio-temporal information about the BSS and the city’s mobility

Teoría del encaminamiento en redes ad hoc inalámbricas

Las Redes Ad Hoc Inalámbricas gozan de un gran auge hoy en día debido a que dan respuesta a las exigencias actuales referentes al establecimiento de redes que cubran necesidades de comunicación de forma flexible -en tiempo y espacio- y autónoma -autoconfiguración e independencia de una estructura fija-. Estas características suponen importantes retos de diseño que obligan a desarrollar propuestas novedosas, capaces de superar las restricciones impuestas por la variabilidad en la topología y el canal y la ausencia de infraestructura. Entre el elevado número de aspectos que se ven alterados por este nuevo planteamiento de las redes de comunicación, el encaminamiento es uno de los más afectados. Este hecho es especialmente significativo debido a que, al mismo tiempo, una parte importante del nivel de las prestaciones finales ofrecidas por las Redes Ad Hoc Inalámbricas recae sobre el mismo. La presente tesis aborda el estudio del encaminamiento en Redes Ad Hoc Inalámbricas desde un punto de vista teórico-práctico que lo describe de forma global. Esta perspectiva que aúna teoría y experiencia supone una innovación significativa en este ámbito, donde, hasta donde alcanza nuestro conocimiento, ambas aproximaciones al conocimiento se tratan de forma absolutamente independiente hasta la fecha. El planteamiento integral permite que se establezcan fuertes interrelaciones con otras interpretaciones de este campo de estudio con origen en la Teoría de la Información, de la Comunicación, del Control o de Grafos. En lo concerniente al aspecto teórico, la presente tesis desarrolla un modelo con el ánimo de caracterizar el encaminamiento en Redes Ad Hoc Inalámbricas de forma completa, genérica, única y medible. De esta forma, todos los factores involucrados son reunidos bajo un solo parámetro que representa cualquier escenario posible, mediante un valor numérico. El ambicioso objetivo de dotar al modelo teórico de las cualidades anteriores parte del nivel más esencial del encaminamiento: su capacidad para establecer caminos entre fuente y destino que se ajusten a la línea recta que conecta una y otro. Esta capacidad es descrita mediante la llamada eficiencia de encaminamiento, expresada como el cociente entre la distancia entre fuente y destino y la longitud de la ruta que los une. Así, se persiguen los rasgos de completitud y generalidad. El conjunto de todos los valores posibles de la eficiencia de encaminamiento para un escenario determinado es recogido en su distribución estadística, que se representa por la magnitud de una sola variable denominada radio de persistencia. Por consiguiente, se añaden las deseadas unicidad y mensurabilidad al modelo propuesto. A su vez, el modelo teórico denota la existencia de una relación directa entre el conocimiento espacial de los nodos acerca de la red y la eficiencia de encaminamiento, así como la dependencia de ésta con la dimensión. En este sentido, se aporta la expresión de la distribución estadística de la eficiencia de encaminamiento en D dimensiones. El modelo propuesto es validado de forma empírica. El conjunto de experimentos que se lleva a cabo obedece a una metodología de diseño creada al efecto de asegurar la corrección de los resultados así como su reproducibilidad. Esta metodología es especialmente relevante para establecer un marco común de experimentación de tal forma que, por una parte, sea posible la comparación directa de los resultados obtenidos y, por otra, éstos sean representativos del fenómeno bajo análisis. Asimismo, la confirmación del modelo teórico se realiza mediante la comprobación de que las medidas experimentales recogidas son caracterizadas por un valor concreto del radio de persistencia. Por este motivo, se crea un procedimiento específico para el ajuste de la distribución estadística experimental a la teórica, que produce tanto la magnitud absoluta representativa como su rango de variación. El desarrollo teórico y empírico aportado por la presente tesis genera un marco de estudio y evaluación del encaminamiento en Redes Ad Hoc Inalámbricas sobre una base sólida, objetiva y equitativa. En el mismo, sus prestaciones son definidas de forma absoluta mediante la medida de su radio de persistencia, abandonando la mera comparación relativa de ciertos aspectos particularizados a las condiciones específicas del caso analizado. Por consiguiente, a través del mismo, es posible el estudio del encaminamiento en Redes Ad Hoc Inalámbricas desde un punto de vista completo -teórico y experimental- e integral -que considera todas las contribuciones de los distintos factores involucrados en el mismo-, lo que permite futuros desarrollos en este campo de investigación. ____________________________________________Wireless Ad Hoc Networks give response to current requirements regarding the establishment of networks that fulfill communication needs in a flexible -in time and space- and autonomous -autoconfiguration and independence from a fixed structure- way. These features imply important challenges in design that force the development of new proposals which overcome the restrictions that are imposed by the presence of variability in the topology and channel and the absence of an infrastructure. This novel approach of a communication network impacts on different aspects. Among them, routing is one of the most affected. This is especially significant due to the fact that, at the same time, routing is responsible of a relevant piece of the final level of performance of the network. This thesis faces the study of routing in Wireless Ad Hoc Networks from a theoretical and practical perspective that describes it globally. This outlook produces a significant innovation in this field, where, to the best of our knowledge, both approximations are seen in a completely separate way. The integral approach allows establishing strong relationships with other interpretations in this area under the scope of the Information Theory, Communication Theory, Control Theory or Graph Theory. Regarding the theoretical aspect, the present thesis develops a model that characterizes routing in Wireless Ad Hoc Networks in a complete, generic, unique and measurable way. Hence, all the included factors are collected under a single parameter that represents any possible scenario by means of a numeric value. This ambitious aim of providing the theoretical model with the previous qualities starts from the most essential level of routing: its ability to establish paths from source to destination which are as close as possible to the straight line that connects both. This ability is described through the so called routing efficiency, which is expressed as the ratio between the Euclidean distance between source and destination and the actual length of the route. Thus, the completeness and generality features are reached. The set of every permitted value of the routing efficiency in a specific scenario is present in its statistical distribution, which is characterized by a single variable named persistence radius. Consequently, the desired properties of uniqueness and measurability are added. Furthermore, the theoretical model points out the existence of a direct relation between the spatial knowledge of the nodes regarding the network and the routing efficiency, which in addition depends on the dimension of the network. Therefore, the expression of the statistical distribution of the routing efficiency in D dimensions is included. The theoretical model is validated through simulation. The set of experiments that are carried out follow a methodology for their design created in order to assure the correction of the results and its reproducibility. This methodology is especially relevant to establish a common experimental framework. With this framework, the obtained results can be directly compared and are representative of the object under analysis. Additionally, the validation of the theoretical model is implemented verifying that the collected empirical measures are characterized by a particular value of the persistence radius. Because of this, a specific procedure is created to fit the experimental to the theoretical statistical distributions. This fitting generates both the absolute magnitude and its range of variation. The theoretical and empirical development included in this thesis builds a framework for the study and evaluation of routing in Wireless Ad Hoc Networks from a solid, objective and equitable basis. The routing performance is defined in an absolute way through the measure of its persistence radius, thus avoiding the relative comparison of several aspects particularized by the specific conditions of the analyzed case. Consequently, this framework allows the study of routing in Wireless Ad Hoc Networks from a complete -theoretical and practical- and integral -that considers every factor involved in it- point of view, which empowers future developments in this research field

Moped Scooter Sharing: Citizens’ Perceptions, Users’ Behavior, and Implications for Urban Mobility

In recent years, moped-style scooter sharing is gaining increasing attention in many urban areas worldwide. Nevertheless, research contributions are still limited, unlike other shared mobility systems. This paper is aimed at providing a first insight on moped sharing demand by exploring the usage and opinions towards this new mobility alternative. To that end, the research exploits the data from a web-based survey conducted in Spain, one of the countries with the largest implementation around the world in terms of the shared e-mopeds fleet. Kruskal–Wallis tests were conducted to identify the segment of the urban population that is more likely adopted moped sharing, and additional statistical mean differences in specific variables concerning moped sharing were carried out. The paper also provides a better understanding of the shared mopeds market and some implications for urban mobility, such as the potential role of shared mopeds in reducing vehicle ownership and its effect on urban modal shift. Furthermore, two discrete choice models were developed to (i) analyze the key drivers determining the willingness to use moped sharing, and (ii) explore individuals’ opinions on whether owning a private vehicle will not be a need in the future. The results indicate that age, occupation, income, and environmental awareness seem to be among the main reasons behind the potential use of these services in the future. The results may be useful for both operators and transport planners when designing actions and policy efforts addressing this mobility option and urban mobility in general