Modelo teórico para la reconstrucción de accidentes de tráfico por ordenador

Los accidentes de tráfico se han convertido en uno de los problemas de salud pública mas graves. El objetivo global de esta tesis doctoral es el estudio y desarrollo de un modelo teórico para la simulación y reconstrucción de accidentes de tráfico por ordenador. Tras mostrar unos antecedentes acerca del tema abordado, se desarrolla y explica un lenguaje informático para a la simulación de sistemas dinámicos por ordenador, denominado "Blove". Utilizando el lenguaje "Blove", se desarrollan los modelos vehiculares y de choque necesarios para la simulación de accidentes de tráfico. Se estudia y resuelve el problema del control direccional del modelo de simulación vehicular, así como la representación de la geometría de la calzada. Se desarrolla un algorítmo para la optimización de la reconstrucción de accidentes de tráfico, que permite hallar la velocidad de los vehículos en el instante de su colisión, en función de las consecuencias conocidas del accidente. A continuación, se describe un sistema informático de reconstrucción de accidentes de tráfico, abordando el problema del tratamiento de los datos necesarios. Por último, se realiza la validación de los modelos de simulación desarrollados y del algorítmo de optimización de la reconstrucción de accidentes de tráfico. Para esta validación, se utilizan datos de ensayos experimentales de choque y de diversos accidentes de tráfico reales. Se acaba exponiendo las conclusiones de esta tesis y las futuras líneas de investigación que se pueden derivar de ella

Metaheuristic Optimization Frameworks: a Survey and Benchmarking

This paper performs an unprecedented comparative study of Metaheuristic optimization frameworks. As criteria for comparison a set of 271 features grouped in 30 characteristics and 6 areas has been selected. These features include the different metaheuristic techniques covered, mechanisms for solution encoding, constraint handling, neighborhood specification, hybridization, parallel and distributed computation, software engineering best practices, documentation and user interface, etc. A metric has been defined for each feature so that the scores obtained by a framework are averaged within each group of features, leading to a final average score for each framework. Out of 33 frameworks ten have been selected from the literature using well-defined filtering criteria, and the results of the comparison are analyzed with the aim of identifying improvement areas and gaps in specific frameworks and the whole set. Generally speaking, a significant lack of support has been found for hyper-heuristics, and parallel and distributed computing capabilities. It is also desirable to have a wider implementation of some Software Engineering best practices. Finally, a wider support for some metaheuristics and hybridization capabilities is needed

Verified Computer Algebra in ACL2 (Gröbner Bases Computation)

In this paper, we present the formal verification of a Common Lisp implementation of Buchberger’s algorithm for computing Gröbner bases of polynomial ideals. This work is carried out in the Acl2 system and shows how verified Computer Algebra can be achieved in an executable logic

Digital quantification of effects of admixtures on early shrinkage cracking

The study of the effect of early shrinkage is important to prevent aesthetic defects and, especially, to avoid the reduction of durability of concrete elements due to surface cracking. This paper presents the application of a new digital imaging methodology to quantify the effects of polypropylene macrofibres, microfibres and glycolether shrinkage reducing admixture (SRA) on early shrinkage cracking. This way, the effectiveness of different admixtures incorporated into the common base mix design of concrete can be compared impartially through the total cracking area, maximum crack width, total crack length, among other parameters that this methodology provides. The results demonstrate the great capacity of the methodology to isolate and determine the characteristics of an entire cracking pattern, and the similarity of behaviour between admixtures. Nevertheless, the presence of 1 kg/m3 of microfibres leads to the delay and the decrease of early shrinkage cracking pattern.Postprint (published version

Deploying ITS Scenarios Providing Security and Mobility Services Based on IEEE 802.11p Technology

Botany & plant science

Comparative Study of Railway Drive Systems Using Bond-Graph

Since the first railways were built, they have not ceased to increase their capacity for transport, speed and energy consumption. This paper presents a comparative study of how present-day railway drive systems perform. Special emphasis is placed on consumption and energy efficiency. By using theoretical computer simulation models, simulations are conducted of the performance of present-day railway drive systems under certain specific boundary conditions. Bond-Graph Technique has been used to design the models. This technique is widely known and accepted for its suitability and capability for modeling dynamic systems in any field of science or technology, and particularly for modeling vehicular systems. Modeling is done systematically taking account of all the mechanical, dynamic, electrical, electromagnetic and regulation phenomena involved in the operation of railway drive systems. A detailed study of the simulation results has enabled a comparative analysis to be conducted of the most significant variables. Important conclusions have been drawn from this analysis about the drive systems that have been shown to be comparatively more efficient

Using Bond-Graph Technique for Modelling and Simulating Railway Drive Systems

This work presents the application of Bond-Graph Technique to modelling and simulating the behaviour of railway transport as a tool for studying its dynamic behaviour, consumption and energy efficiency, and environmental impact. The basic aim of this study is to make a contribution to the research and innovation into new technologies that will lead to the discovery of ever more efficient environmentally-friendly transport. We begin with an introduction to the study of longitudinal train dynamics as well as a description of the most currently used railway drive systems. Bond-Graph technique enables this modelling to be done systematically taking into account all the fields of science and technology involved while bringing together all the mechanical, electrical, electromagnetic, thermal, dynamic and regulatory aspects. Once the models have been developed, the behaviour of the drive systems is simulated by reproducing actual railway operating conditions along a standard section of track. Through a detailed study of the simulation results and choosing the most significant parameters, a comparison can be made of how the different systems perform. We end with the most important conclusions from which it can be deduced which drive systems are comparatively more efficient and environmentally-friendly

Development and Implementation of a Hybrid Wireless Sensor Network of Low Power and Long Range for Urban Environments

The urban population, worldwide, is growing exponentially and with it the demand for information on pollution levels, vehicle traffic, or available parking, giving rise to citizens connected to their environment. This article presents an experimental long range (LoRa) and low power consumption network, with a combination of static and mobile wireless sensors (hybrid architecture) to tune and validate concentrator placement, to obtain a large coverage in an urban environment. A mobile node has been used, carrying a gateway and various sensors. The Activation By Personalization (ABP) mode has been used, justified for urban applications requiring multicasting. This allows to compare the coverage of each static gateway, being able to make practical decisions about its location. With this methodology, it has been possible to provide service to the city of Malaga, through a single concentrator node. The information acquired is synchronized in an external database, to monitor the data in real time, being able to geolocate the dataframes through web mapping services. This work presents the development and implementation of a hybrid wireless sensor network of long range and low power, configured and tuned to achieve efficient performance in a mid-size city, and tested in experiments in a real urban environment.Spanish project RTI2018-093421-B-I0

Patrón primario de ruido térmico de banda ancha

Número de publicación: 2 415 083 Número de solicitud: 201130156Patrón primario de ruido térmico de banda ancha. Sistema coaxial para un patrón primario empleado en la trazabilidad de fuentes de ruido térmico, que comprende una línea de transmisión coaxial y un anillo, estando una parte de la línea de transmisión coaxial sumergida en nitrógeno líquido y otra parte de la línea de transmisión coaxial rodeada por un circuito de agua donde se encuentra el anillo, comprendiendo la citada línea de transmisión coaxial un conductor exterior y un conductor interior, estando ambos conductores unidos mediante el anillo que está realizado en un material que garantiza la conductividad térmica entre el conductor exterior y el conductor interior, comprendiendo el anillo un tramo central en contacto en toda su longitud con la superficie interior del conductor exterior, y porque la relación entre el radio del conductor interior y el radio exterior del anillo es tal que en toda la longitud del anillo la impedancia es la misma que la impedancia nominal de la línea coaxial.Universidad Politécnica de CartagenaInstituto Nacional de Técnica Aeroespacial (INTA

SROI Methodology for Public Administration Decisions about Financing with Social Criteria. A Case Study

: The measurement of impacts has been considered one of the best methodologies to evaluate the level of achievement of social entities’ objectives as well as of their contribution to resolving social problems. Those methodologies can guide public policies and subsidies granting, as they help to identify the organizations producing a higher social value, and the effects of their projects. Our research focused on the effectiveness and the efficiency of social entities, measured through their capacity to generate impacts on their stakeholders. The research was realized through the analysis of a case study: the special education center for disabled youths, CEE-SA, in Spain. The social return on investment (SROI) methodology has allowed us to monetarize the social value created for stakeholders through the activity carried out by CEE-SA, and it provides information about the whole value creation process that is generated, for which the analysis and follow-up through the indicators offers a contribution to its management system. This case study can serve as a reference in assessing the management processes of similar entities and can also highlight SROI usefulness for public administrations as an assessment tool for subsidies granted on social criteria. The originality of this research relies on the new SROI methodology provided for the assessment of public financing decisions, especially in a field that remains as under-researched as special education schools