Modelling of short runout propagation landslides and debris flows

This paper proposes an extension of methods used to predict the propagation of landslides having a long runout to smaller landslides with much shorter propagation distances. The method is based on: (1) a depth-integrated mathematical model including the coupling between the soil skeleton and the pore fluids, (2) suitable rheological models describing the relation between the stress and the rate of deformation tensors for fluidised soils and (3) a meshless numerical method, Smooth Particle Hydrodynamics, which separates the computational mesh (or set of computational nodes) from the mesh describing the terrain topography, which is of structured type – thus accelerating search operations. The proposed model is validated using two examples for which there are analytical solutions, and then it is applied to two short runout landslides which happened in Hong Kong in 1995, for which there is available information.

Influencia de la configuración geométrica de placas prefabricadas para forjados en las tensiones originadas por la transferencia del pretensado en elementos realizados con armaduras pretesas ancladas por adherencia

Las piezas pretensadas de hormigón presentan zonas muy solicitadas correspondientes a la zona de transferencia. En muchos casos se ha detectado figuración en tales zonas cuyo origen está ligado a la transferencia de la fuerza de pretensado, pudiendo llegar a causar el rechazo de la pieza. En el caso de las piezas prefabricadas con armaduras pretesas adherentes, no siempre es posible disponer armado transversal para controlar esta fisuración, ya sea por el proceso constructivo, ya sea por disponer en general de secciones transversales muy optimizadas. Recientemente se desarrolló una nueva tipología de piezas de hormigón prefabricado para forjados unidireccionales pretensadas con armadura activa pretesa y sin armadura transversal. La tipología se asimila a una sección en PI invertida, con alas de gran envergadura en comparación con el ancho de nervio, y armadura activa distribuida en las alas. Este diseño parece propenso a la aparición de fisuración en el momento de la transferencia del pretensado. Así, se han producido fallos de carácter frágil: colapso de piezas ya colocadas en obra, separándose la losa inferior de los nervios y cayendo sobre el piso. Las herramientas de análisis usuales han resultado inútiles al aplicarse a la investigación de esta patología. Para afrontar el estudio de los problemas detectados en la tipología, se ha analizado el fenómeno de las tensiones de tracción en la zona de transferencia, usualmente denominadas exfoliación y estallido, así como los métodos de análisis aplicables a elementos pretesos sin armadura transversal. En algunas ocasiones se trata del resultado de trabajos desarrollados para piezas postesadas, o para calcular cuantías de armadura transversal, adaptados a posteriori. También existen métodos desarrollados específicamente para piezas pretesas sin armadura transversal. Junto a los factores considerados en los métodos existentes se han localizado otros, no tenidos en cuenta habitualmente, pero que pueden ser determinantes en piezas no convencionales, como son: la existencia de pretensado superior e inferior, la falta de simetría de la sección transversal, el ancho variable de las piezas, una relación entre el ancho del ala y el espesor de los nervios elevada, la distribución transversal del pretensado en relación al ancho variable. Además, la mayoría de los métodos se han basado en simplificaciones bidimensionales. Para tener en cuenta la influencia de estos factores, se han modelizado piezas en las que varían tanto la geometría de la sección transversal y la cuantía de pretensado, como la ley de adherencia o la distribución de armadura activa en la sección. Estos modelos se han analizado mediante el método de elementos finitos, efectuándose u análisis elástico lineal tridimensional. En general, los métodos existentes no han predicho adecuadamente las tensiones obtenidas mediante elementos finitos. Sobre los resultados obtenidos por elementos finitos se ha desarrollado un ajuste experimental, que presentan un alto grado de correlación y de significación, así como una reducida dispersión y error relativo. En consecuencia, se propone un método de obtención de la tensión máxima de exfoliación, consistente en varias ecuaciones, que tienen en cuenta las peculiaridades de la configuración de las piezas citadas y permiten considerar cualquier ley de adherencia, manteniendo la coherencia con la longitud de transmisión. Las ecuaciones se emplean para la obtención de la tensión máxima de exfoliación en piezas de la tipología estudiada cuya armadura activa se sitúe fuera del núcleo central de la sección transversal. Respecto al estallido, se propone una modificación de los métodos existentes que, comparado con los resultados del análisis por elementos finitos, mejora el valor medio y la dispersión a valores admisibles y del lado de la seguridad. El método considera la geometría de la sección y la distribución del pretensado en la losa inferior. Finalmente, se ofrecen estrategias de diseño para piezas de la tipología o semejantes. End zones of prestressed concrete members are highly stressed. Cracking have often appeared at end zone, and its beginning is related to prestress release. Some members become rejected because of these cracks. Sometimes it is not possible having transverse reinforcement in order to control cracking, when referring to pretensioned precast members. The reason may be the construction process or highly optimized crosssections. A new typology of precast concrete members designed for one-way composite floors was recently developed. The members, without transverse reinforcement, are prestressed with pretensioned wires or strands. This typology is similar to an inverted TT slab, with a large flange related to the web thickness and prestressing reinforcement spread across the flange. This design is highly susceptible to appear cracking at prestress release. Therefore, brittle failures have been reported: fail of slabs laid in place on a construction site, resulting in the separation of the flange from the webs,, and the subsequent fall on the lower floor. Usual analytical methods have been useless to study the failure. End zone tensile stresses have been analysed to study the detected typology problems. These tensile stresses are usually called spalling and bursting (also called splitting in the U.S.). Analysis methods applicable to pretensioned members without transverse reinforcement have been analysed too. Some methods were originally developed for postensioned concrete or for obtaining the amount of transverse reinforcement. In addition, there are methods developed specifically for pretensioned members without transverse reinforcement. Some factors, frequently ignored, have been found, such as lower and upper prestress, lack of symmetry in the cross section, variable width, a high ratio between flange width and web thickness or prestressing reinforcement location related to variable width. They can play a decisive role in non-conventional members. In addition, most methods are based on 2D simplifications. Finite Element modelling has been conducted in order to consider the influence of these factors. A linear 3D approach has been used. The modelled members vary according to cross section geometry, bond behaviour, or prestressing reinforcement location. In general, the obtained tensile stresses don’t agree with existing methods. An experimental adjustment has been conducted on the obtained results, with a high correlation ratio and significance level as well as a low dispersion and relative error. Therefore, a method to obtain the maximum spalling stress is proposed. The proposal consists on some equations that consider the special features of the typology and bond behaviour. Consistency between transmission length and bond behaviour is considered too. The equations are used to calculate maximum spalling stress for the studied typology members whose prestressing reinforcement is located out of the core of the cross section. In relation to bursting, a modification of existing methods is proposed. Compared to finite element results, the proposal improves mean value and dispersion, whose ranges are considered acceptable and secure. The method takes into account cross section geometry and location of prestressing reinforcement across the lower flange. Finally, strategies to design members of this typology or similar are proposed.

Evaluating a web-based clinical decision support system for language disorders screening in a nursery school

Background: Early and effective identification of developmental disorders during childhood remains a critical task for the international community. The second highest prevalence of common developmental disorders in children are language delays, which are frequently the first symptoms of a possible disorder. Objective: This paper evaluates a Web-based Clinical Decision Support System (CDSS) whose aim is to enhance the screening of language disorders at a nursery school. The common lack of early diagnosis of language disorders led us to deploy an easy-to-use CDSS in order to evaluate its accuracy in early detection of language pathologies. This CDSS can be used by pediatricians to support the screening of language disorders in primary care. Methods: This paper details the evaluation results of the ?Gades? CDSS at a nursery school with 146 children, 12 educators, and 1 language therapist. The methodology embraces two consecutive phases. The first stage involves the observation of each child?s language abilities, carried out by the educators, to facilitate the evaluation of language acquisition level performed by a language therapist. Next, the same language therapist evaluates the reliability of the observed results. Results: The Gades CDSS was integrated to provide the language therapist with the required clinical information. The validation process showed a global 83.6% (122/146) success rate in language evaluation and a 7% (7/94) rate of non-accepted system decisions within the range of children from 0 to 3 years old. The system helped language therapists to identify new children with potential disorders who required further evaluation. This process will revalidate the CDSS output and allow the enhancement of early detection of language disorders in children. The system does need minor refinement, since the therapists disagreed with some questions from the CDSS knowledge base (KB) and suggested adding a few questions about speech production and pragmatic abilities. The refinement of the KB will address these issues and include the requested improvements, with the support of the experts who took part in the original KB development. Conclusions: This research demonstrated the benefit of a Web-based CDSS to monitor children?s neurodevelopment via the early detection of language delays at a nursery school. Current next steps focus on the design of a model that includes pseudo auto-learning capacity, supervised by experts.

Structuring research methods and data with the research object model: genomics workflows as a case study

Background: One of the main challenges for biomedical research lies in the computer-assisted integrative study of large and increasingly complex combinations of data in order to understand molecular mechanisms. The preservation of the materials and methods of such computational experiments with clear annotations is essential for understanding an experiment, and this is increasingly recognized in the bioinformatics community. Our assumption is that offering means of digital, structured aggregation and annotation of the objects of an experiment will provide necessary meta-data for a scientist to understand and recreate the results of an experiment. To support this we explored a model for the semantic description of a workflow-centric Research Object (RO), where an RO is defined as a resource that aggregates other resources, e.g., datasets, software, spreadsheets, text, etc. We applied this model to a case study where we analysed human metabolite variation by workflows. Results: We present the application of the workflow-centric RO model for our bioinformatics case study. Three workflows were produced following recently defined Best Practices for workflow design. By modelling the experiment as an RO, we were able to automatically query the experiment and answer questions such as “which particular data was input to a particular workflow to test a particular hypothesis?”, and “which particular conclusions were drawn from a particular workflow?”. Conclusions: Applying a workflow-centric RO model to aggregate and annotate the resources used in a bioinformatics experiment, allowed us to retrieve the conclusions of the experiment in the context of the driving hypothesis, the executed workflows and their input data. The RO model is an extendable reference model that can be used by other systems as well.

The usefulness of Usability and User Experience evaluation methods on an e-Learning platform development from a developer's perspective: A case study

The development of a web platform is a complex and interdisciplinary task, where people with different roles such as project manager, designer or developer participate. Different usability and User Experience evaluation methods can be used in each stage of the development life cycle, but not all of them have the same influence in the software development and in the final product or system. This article presents the study of the impact of these methods applied in the context of an e-Learning platform development. The results show that the impact has been strong from a developer's perspective. Developer team members considered that usability and User Experience evaluation allowed them mainly to identify design mistakes, improve the platform's usability and understand the end users and their needs in a better way. Interviews with potential users, clickmaps and scrollmaps were rated as the most useful methods. Finally, these methods were considered unanimously very useful in the context of the entire software development, only comparable to SCRUM meetings and overcoming the rest of involved factors.

Creating and modelling personal socio-economic networks in on-line banking

The banking industry is observing how new competitors threaten its millennial business model by targeting unbanked people, offering new financial services to their customer base, and even enabling new channels for existing services and customers. The knowledge on users, their behaviour, and expectations become a key asset in this new context. Well aware of this situation, the Center for Open Middleware, a joint technology center created by Santander Bank and Universidad Politécnica de Madrid, has launched a set of initiatives to allow the experimental analysis and management of socio-economic information. PosdataP2P service is one of them, which seeks to model the economic ties between the holders of university smart cards, leveraging on the social networks the holders are subscribed to. In this paper we describe the design principles guiding the development of the system, its architecture and some implementation details.

Laser Shock Microforming of Thin Metal Sheets: Physical Principles, Modelling and Experimental Implementation

The increasing demands in MEMS fabrication are leading to new requirements in production technology. Especially the packaging and assembly require high accuracy in positioning and high reproducibility in combination with low production costs. Conventional assembly technology and mechanical adjustment methods are time consuming and expensive. Each component of the system has to be positioned and fixed. Also adjustment of the parts after joining requires additional mechanical devices that need to be accessible after joining. Accurate positioning of smallest components represents an up-to-date key assignment in micro-manufacturing. It has proven to be more time and cost efficient to initially assemble the components with widened tolerances before precisely micro-adjusting them in a second step.

Context modelling for natural Human Computer Interaction applications in e-health

The conception of IoT (Internet of Things) is accepted as the future tendency of Internet among academia and industry. It will enable people and things to be connected at anytime and anyplace, with anything and anyone. IoT has been proposed to be applied into many areas such as Healthcare, Transportation，Logistics, and Smart environment etc. However, this thesis emphasizes on the home healthcare area as it is the potential healthcare model to solve many problems such as the limited medical resources, the increasing demands for healthcare from elderly and chronic patients which the traditional model is not capable of. A remarkable change in IoT in semantic oriented vision is that vast sensors or devices are involved which could generate enormous data. Methods to manage the data including acquiring, interpreting, processing and storing data need to be implemented. Apart from this, other abilities that IoT is not capable of are concluded, namely, interoperation, context awareness and security & privacy. Context awareness is an emerging technology to manage and take advantage of context to enable any type of system to provide personalized services. The aim of this thesis is to explore ways to facilitate context awareness in IoT. In order to realize this objective, a preliminary research is carried out in this thesis. The most basic premise to realize context awareness is to collect, model, understand, reason and make use of context. A complete literature review for the existing context modelling and context reasoning techniques is conducted. The conclusion is that the ontology-based context modelling and ontology-based context reasoning are the most promising and efficient techniques to manage context. In order to fuse ontology into IoT, a specific ontology-based context awareness framework is proposed for IoT applications. In general, the framework is composed of eight components which are hardware, UI (User Interface), Context modelling, Context fusion, Context reasoning, Context repository, Security unit and Context dissemination. Moreover, on the basis of TOVE (Toronto Virtual Enterprise), a formal ontology developing methodology is proposed and illustrated which consists of four stages: Specification & Conceptualization, Competency Formulation, Implementation and Validation & Documentation. In addition, a home healthcare scenario is elaborated by listing its well-defined functionalities. Aiming at representing this specific scenario, the proposed ontology developing methodology is applied and the ontology-based model is developed in a free and open-source ontology editor called Protégé. Finally, the accuracy and completeness of the proposed ontology are validated to show that this proposed ontology is able to accurately represent the scenario of interest.

Methods and Techniques for Segmentation of Consumers in Social Media

Los medios sociales han revolucionado la manera en la que los consumidores se relacionan entre sí y con las marcas. Las opiniones publicadas en dichos medios tienen un poder de influencia en las decisiones de compra tan importante como las campañas de publicidad. En consecuencia, los profesionales del marketing cada vez dedican mayores esfuerzos e inversión a la obtención de indicadores que permitan medir el estado de salud de las marcas a partir de los contenidos digitales generados por sus consumidores. Dada la naturaleza no estructurada de los contenidos publicados en los medios sociales, la tecnología usada para procesar dichos contenidos ha menudo implementa técnicas de Inteligencia Artificial, tales como algoritmos de procesamiento de lenguaje natural, aprendizaje automático y análisis semántico. Esta tesis, contribuye al estado de la cuestión, con un modelo que permite estructurar e integrar la información publicada en medios sociales, y una serie de técnicas cuyos objetivos son la identificación de consumidores, así como la segmentación psicográfica y sociodemográfica de los mismos. La técnica de identificación de consumidores se basa en la huella digital de los dispositivos que utilizan para navegar por la Web y es tolerante a los cambios que se producen con frecuencia en dicha huella digital. Las técnicas de segmentación psicográfica descritas obtienen la posición en el embudo de compra de los consumidores y permiten clasificar las opiniones en función de una serie de atributos de marketing. Finalmente, las técnicas de segmentación sociodemográfica permiten obtener el lugar de residencia y el género de los consumidores. ABSTRACT Social media has revolutionised the way in which consumers relate to each other and with brands. The opinions published in social media have a power of influencing purchase decisions as important as advertising campaigns. Consequently, marketers are increasing efforts and investments for obtaining indicators to measure brand health from the digital content generated by consumers. Given the unstructured nature of social media contents, the technology used for processing such contents often implements Artificial Intelligence techniques, such as natural language processing, machine learning and semantic analysis algorithms. This thesis contributes to the State of the Art, with a model for structuring and integrating the information posted on social media, and a number of techniques whose objectives are the identification of consumers, as well as their socio-demographic and psychographic segmentation. The consumer identification technique is based on the fingerprint of the devices they use to surf the Web and is tolerant to the changes that occur frequently in such fingerprint. The psychographic profiling techniques described infer the position of consumer in the purchase funnel, and allow to classify the opinions based on a series of marketing attributes. Finally, the socio-demographic profiling techniques allow to obtain the residence and gender of consumers.

Herramienta Web para el modelado de consultas CEP (Complex Event Processing)

RESUMEN En los últimos años, debido al incremento en la demanda por parte de las empresas de tecnologías que posibiliten la monitorización y el análisis de un gran volumen de datos en tiempo real, la tecnología CEP (Complex Event Processing) ha surgido como una potencia en alza y su uso se ha incrementado notablemente en ciertos sectores como, por ejemplo, la gestión y automatización de procesos de negocios, finanzas, monitorización de redes y aplicaciones, así como redes de sensores inteligentes como el caso de estudio en el que nos centraremos. CEP se basa en un lenguaje de procesamiento de eventos (Event Processing Language,EPL) cuya utilización puede resultar bastante compleja para usuarios inexpertos. Esta complejidad supone un hándicap y, por lo tanto, un problema a la hora de que su uso se extienda. Este Proyecto Fin de Grado (PFG) pretende dar una solución a este problema, acercando al usuario la tecnología CEP mediante técnicas de abstracción y modelado. Para ello, este PFG ha definido un lenguaje de modelado específico dominio, sencillo e intuitivo para el usuario inexperto, al que se ha dado soporte mediante el desarrollo de una herramienta de modelado gráfico (CEP Modeler) en la que se pueden modelar consultas CEP de forma gráfica, sencilla y de manera más accesible para el usuario. ABSTRACT Over recent years, more and more companies demand technology for monitoring and analyzing a vast volume of data in real time. In this regard, the CEP technology (Complex Event Processing) has emerged as a novel approach to that end, and its use has increased dramatically in certain domains, such as, management and automation of business processes, finance, monitoring of networks and applications, as well as smart sensor networks as the case study in which we will focus. CEP is based on in the Event Processing Language (EPL). This language can be rather difficult to use for new users. This complexity can be a handicap, and therefore, a problem at the time of extending its use. This project aims to provide a solution to this problem, trying to approach the CEP technology to users through abstraction and modelling techniques. To that end, this project has defined an intuitive and simple domain-specific modelling language for new users through a web tool (CEP Modeler) for graphically modeling CEP queries, in an easier and more accessible way.

Modelado y Comparación de Colecciones en la Web Semántica

En esta tesis se estudia la representación, modelado y comparación de colecciones mediante el uso de ontologías en el ámbito de la Web Semántica. Las colecciones, entendidas como agrupaciones de objetos o elementos con entidad propia, son construcciones que aparecen frecuentemente en prácticamente todos los dominios del mundo real, y por tanto, es imprescindible disponer de conceptualizaciones de estas estructuras abstractas y de representaciones de estas conceptualizaciones en los sistemas informáticos, que definan adecuadamente su semántica. Mientras que en muchos ámbitos de la Informática y la Inteligencia Artificial, como por ejemplo la programación, las bases de datos o la recuperación de información, las colecciones han sido ampliamente estudiadas y se han desarrollado representaciones que responden a multitud de conceptualizaciones, en el ámbito de la Web Semántica, sin embargo, su estudio ha sido bastante limitado. De hecho hasta la fecha existen pocas propuestas de representación de colecciones mediante ontologías, y las que hay sólo cubren algunos tipos de colecciones y presentan importantes limitaciones. Esto impide la representación adecuada de colecciones y dificulta otras tareas comunes como la comparación de colecciones, algo crítico en operaciones habituales como las búsquedas semánticas o el enlazado de datos en la Web Semántica. Para solventar este problema esta tesis hace una propuesta de modelización de colecciones basada en una nueva clasificación de colecciones de acuerdo a sus características estructurales (homogeneidad, unicidad, orden y cardinalidad). Esta clasificación permite definir una taxonomía con hasta 16 tipos de colecciones distintas. Entre otras ventajas, esta nueva clasificación permite aprovechar la semántica de las propiedades estructurales de cada tipo de colección para realizar comparaciones utilizando las funciones de similitud y disimilitud más apropiadas. De este modo, la tesis desarrolla además un nuevo catálogo de funciones de similitud para las distintas colecciones, donde se han recogido las funciones de (di)similitud más conocidas y también algunas nuevas. Esta propuesta se ha implementado mediante dos ontologías paralelas, la ontología E-Collections, que representa los distintos tipos de colecciones de la taxonomía y su axiomática, y la ontología SIMEON (Similarity Measures Ontology) que representa los tipos de funciones de (di)similitud para cada tipo de colección. Gracias a estas ontologías, para comparar dos colecciones, una vez representadas como instancias de la clase más apropiada de la ontología E-Collections, automáticamente se sabe qué funciones de (di)similitud de la ontología SIMEON pueden utilizarse para su comparación. Abstract This thesis studies the representation, modeling and comparison of collections in the Semantic Web using ontologies. Collections, understood as groups of objects or elements with their own identities, are constructions that appear frequently in almost all areas of the real world. Therefore, it is essential to have conceptualizations of these abstract structures and representations of these conceptualizations in computer systems, that define their semantic properly. While in many areas of Computer Science and Artificial Intelligence, such as Programming, Databases or Information Retrieval, the collections have been extensively studied and there are representations that match many conceptualizations, in the field Semantic Web, however, their study has been quite limited. In fact, there are few representations of collections using ontologies so far, and they only cover some types of collections and have important limitations. This hinders a proper representation of collections and other common tasks like comparing collections, something critical in usual operations such as semantic search or linking data on the Semantic Web. To solve this problem this thesis makes a proposal for modelling collections based on a new classification of collections according to their structural characteristics (homogeneity, uniqueness, order and cardinality). This classification allows to define a taxonomy with up to 16 different types of collections. Among other advantages, this new classification can leverage the semantics of the structural properties of each type of collection to make comparisons using the most appropriate (dis)similarity functions. Thus, the thesis also develops a new catalog of similarity functions for the different types of collections. This catalog contains the most common (dis)similarity functions as well as new ones. This proposal is implemented through two parallel ontologies, the E-Collections ontology that represents the different types of collections in the taxonomy and their axiomatic, and the SIMEON ontology (Similarity Measures Ontology) that represents the types of (dis)similarity functions for each type of collection. Thanks to these ontologies, to compare two collections, once represented as instances of the appropriate class of E-Collections ontology, we can know automatically which (dis)similarity functions of the SIMEON ontology are suitable for the comparison. Finally, the feasibility and usefulness of this modeling and comparison of collections proposal is proved in the field of oenology, applying both E-Collections and SIMEON ontologies to the representation and comparison of wines with the E-Baco ontology.

Modelling ecological cognitive rehabilitation therapies for building virtual environments in brain injury

Brain Injury (BI) has become one of the most common causes of neurological disability in developed countries. Cognitive disorders result in a loss of independence and patients? quality of life. Cognitive rehabilitation aims to promote patients? skills to achieve their highest degree of personal autonomy. New technologies such as virtual reality or interactive video allow developing rehabilitation therapies based on reproducible Activities of Daily Living (ADLs), increasing the ecological validity of the therapy. However, the lack of frameworks to formalize and represent the definition of this kind of therapies can be a barrier for widespread use of interactive virtual environments in clinical routine.

Semantic Support for Computational Land-Use Modelling

Postprint

On the development of advanced techniques for mixed-elastohydrodynamic lubrification modelling of journal and sliding bearing systems.

The present thesis is focused on the development of a thorough mathematical modelling and computational solution framework aimed at the numerical simulation of journal and sliding bearing systems operating under a wide range of lubrication regimes (mixed, elastohydrodynamic and full film lubrication regimes) and working conditions (static, quasi-static and transient conditions). The fluid flow effects have been considered in terms of the Isothermal Generalized Equation of the Mechanics of the Viscous Thin Films (Reynolds equation), along with the massconserving p-Ø Elrod-Adams cavitation model that accordingly ensures the so-called JFO complementary boundary conditions for fluid film rupture. The variation of the lubricant rheological properties due to the viscous-pressure (Barus and Roelands equations), viscous-shear-thinning (Eyring and Carreau-Yasuda equations) and density-pressure (Dowson-Higginson equation) relationships have also been taken into account in the overall modelling. Generic models have been derived for the aforementioned bearing components in order to enable their applications in general multibody dynamic systems (MDS), and by including the effects of angular misalignments, superficial geometric defects (form/waviness deviations, EHL deformations, etc.) and axial motion. The bearing exibility (conformal EHL) has been incorporated by means of FEM model reduction (or condensation) techniques. The macroscopic in fluence of the mixedlubrication phenomena have been included into the modelling by the stochastic Patir and Cheng average ow model and the Greenwood-Williamson/Greenwood-Tripp formulations for rough contacts. Furthermore, a deterministic mixed-lubrication model with inter-asperity cavitation has also been proposed for full-scale simulations in the microscopic (roughness) level. According to the extensive mathematical modelling background established, three significant contributions have been accomplished. Firstly, a general numerical solution for the Reynolds lubrication equation with the mass-conserving p - Ø cavitation model has been developed based on the hybridtype Element-Based Finite Volume Method (EbFVM). This new solution scheme allows solving lubrication problems with complex geometries to be discretized by unstructured grids. The numerical method was validated in agreement with several example cases from the literature, and further used in numerical experiments to explore its exibility in coping with irregular meshes for reducing the number of nodes required in the solution of textured sliding bearings. Secondly, novel robust partitioned techniques, namely: Fixed Point Gauss-Seidel Method (PGMF), Point Gauss-Seidel Method with Aitken Acceleration (PGMA) and Interface Quasi-Newton Method with Inverse Jacobian from Least-Squares approximation (IQN-ILS), commonly adopted for solving uid-structure interaction problems have been introduced in the context of tribological simulations, particularly for the coupled calculation of dynamic conformal EHL contacts. The performance of such partitioned methods was evaluated according to simulations of dynamically loaded connecting-rod big-end bearings of both heavy-duty and high-speed engines. Finally, the proposed deterministic mixed-lubrication modelling was applied to investigate the in fluence of the cylinder liner wear after a 100h dynamometer engine test on the hydrodynamic pressure generation and friction of Twin-Land Oil Control Rings.

Herramientas Web en el proceso de enseñanza y aprendizaje del ciberperiodismo en la Comunidad Valenciana

Internet es un recurso de trabajo imprescindible en la tarea del ciberperiodista. Los profesionales de este campo utilizan la red como fuente de información, para crear, editar y distribuir contenidos informativos. Estas nuevas formas de trabajo, apoyadas en entornos telemáticos, se están haciendo extensibles a la universidad española, donde se está produciendo un proceso de adaptación de metodologías, técnicas y herramientas en los estudios de Periodismo. Para facilitar este proceso de ajuste por parte de los profesores de ciberperiodismo, esta investigación pretende establecer una tipología del uso de estos instrumentos en línea según los objetivos planteados en las guías docentes. Para ello, se han estudiado los programas de las asignaturas relacionadas con la docencia del ciberperiodismo en la Comunidad Valenciana. Se han seleccionado los instrumentos Web más utilizados por los profesores y se han organizado en una tabla según criterios de finalidad, acción y tipo de interacción que realiza el alumno con las herramientas y asimismo los objetivos ciberperiodísticos que pueden lograrse con cada una de ellas. La tabla ofrece información general de cada herramienta. El propósito es facilitar a los profesores un criterio de selección para elegir y profundizar en los espacios e instrumentos docentes más adecuados según las competencias que el alumno debe adquirir durante el proceso de enseñanza y aprendizaje en estos estudios.