A bi-cubic transformation for the numerical evaluation of the Cauchy principal value integrals in boundary methods

The numerical strategies employed in the evaluation of singular integrals existing in the Cauchy principal value (CPV) sense are, undoubtedly, one of the key aspects which remarkably affect the performance and accuracy of the boundary element method (BEM). Thus, a new procedure, based upon a bi-cubic co-ordinate transformation and oriented towards the numerical evaluation of both the CPV integrals and some others which contain different types of singularity is developed. Both the ideas and some details involved in the proposed formulae are presented, obtaining rather simple and-attractive expressions for the numerical quadrature which are also easily embodied into existing BEM codes. Some illustrative examples which assess the stability and accuracy of the new formulae are included.

Impact bruises in pomaceae fruits: Evaluation methods and structural features.

Using a laboratory impact tester, impacts were applied to fruits of different varieties of apples and pears. The response to impact was analized, and many parameters were recorded, to be correlated to bruise susceptibility and to ripeness changes. Different methods for the detection and evaluation of the bruised Area and its features were studied, using direct observation and various reactives. Different types of bruises were established.

Design and control of multi-finger haptic devices for dexterous manipulation

En la interacci��n con el entorno que nos rodea durante nuestra vida diaria (utilizar un cepillo de dientes, abrir puertas, utilizar el tel��fono m��vil, etc.) y en situaciones profesionales (intervenciones m��dicas, procesos de producci��n, etc.), t��picamente realizamos manipulaciones avanzadas que incluyen la utilizaci��n de los dedos de ambas manos. De esta forma el desarrollo de m��todos de interacci��n h��ptica multi-dedo dan lugar a interfaces hombre-m��quina m��s naturales y realistas. No obstante, la mayor��a de interfaces h��pticas disponibles en el mercado est��n basadas en interacciones con un solo punto de contacto; esto puede ser suficiente para la exploraci��n o palpaci��n del entorno pero no permite la realizaci��n de tareas m��s avanzadas como agarres. En esta tesis, se investiga el dise��o mec��nico, control y aplicaciones de dispositivos h��pticos modulares con capacidad de reflexi��n de fuerzas en los dedos ��ndice, coraz��n y pulgar del usuario. El dise��o mec��nico de la interfaz dise��ada, ha sido optimizado con funciones multi-objetivo para conseguir una baja inercia, un amplio espacio de trabajo, alta manipulabilidad y reflexi��n de fuerzas superiores a 3 N en el espacio de trabajo. El ancho de banda y la rigidez del dispositivo se han evaluado mediante simulaci��n y experimentaci��n real. Una de las ��reas m��s importantes en el dise��o de estos dispositivos es el efector final, ya que es la parte que est�� en contacto con el usuario. Durante este trabajo se ha dise��ado un dedal de bajo peso, adaptable a diferentes usuarios que, mediante la incorporaci��n de sensores de contacto, permite estimar fuerzas normales y tangenciales durante la interacci��n con entornos reales y virtuales. Para el dise��o de la arquitectura de control, se estudiaron los principales requisitos para estos dispositivos. Entre estos, cabe destacar la adquisici��n, procesado e intercambio a trav��s de internet de numerosas se��ales de control e instrumentaci��n; la computaci��n de equaciones matem��ticas incluyendo la cinem��tica directa e inversa, jacobiana, algoritmos de detecci��n de agarres, etc. Todos estos componentes deben calcularse en tiempo real garantizando una frecuencia m��nima de 1 KHz. Adem��s, se describen sistemas para manipulaci��n de precisi��n virtual y remota; as�� como el dise��o de un m��todo denominado "desacoplo cinem��tico iterativo" para computar la cinem��tica inversa de robots y la comparaci��n con otros m��todos actuales. Para entender la importancia de la interacci��n multimodal, se ha llevado a cabo un estudio para comprobar qu�� est��mulos sensoriales se correlacionan con tiempos de respuesta m��s r��pidos y de mayor precisi��n. Estos experimentos se desarrollaron en colaboraci��n con neurocient��ficos del instituto Technion Israel Institute of Technology. Comparando los tiempos de respuesta en la interacci��n unimodal (auditiva, visual y h��ptica) con combinaciones bimodales y trimodales de los mismos, se demuestra que el movimiento sincronizado de los dedos para generar respuestas de agarre se basa principalmente en la percepci��n h��ptica. La ventaja en el tiempo de procesamiento de los est��mulos h��pticos, sugiere que los entornos virtuales que incluyen esta componente sensorial generan mejores contingencias motoras y mejoran la credibilidad de los eventos. Se concluye que, los sistemas que incluyen percepci��n h��ptica dotan a los usuarios de m��s tiempo en las etapas cognitivas para rellenar informaci��n de forma creativa y formar una experiencia m��s rica. Una aplicaci��n interesante de los dispositivos h��pticos es el dise��o de nuevos simuladores que permitan entrenar habilidades manuales en el sector m��dico. En colaboraci��n con fisioterapeutas de Griffith University en Australia, se desarroll�� un simulador que permite realizar ejercicios de rehabilitaci��n de la mano. Las propiedades de rigidez no lineales de la articulaci��n metacarpofalange del dedo ��ndice se estimaron mediante la utilizaci��n del efector final dise��ado. Estos par��metros, se han implementado en un escenario que simula el comportamiento de la mano humana y que permite la interacci��n h��ptica a trav��s de esta interfaz. Las aplicaciones potenciales de este simulador est��n relacionadas con entrenamiento y educaci��n de estudiantes de fisioterapia. En esta tesis, se han desarrollado nuevos m��todos que permiten el control simult��neo de robots y manos rob��ticas en la interacci��n con entornos reales. El espacio de trabajo alcanzable por el dispositivo h��ptico, se extiende mediante el cambio de modo de control autom��tico entre posici��n y velocidad. Adem��s, estos m��todos permiten reconocer el gesto del usuario durante las primeras etapas de aproximaci��n al objeto para su agarre. Mediante experimentos de manipulaci��n avanzada de objetos con un manipulador y diferentes manos rob��ticas, se muestra que el tiempo en realizar una tarea se reduce y que el sistema permite la realizaci��n de la tarea con precisi��n. Este trabajo, es el resultado de una colaboraci��n con investigadores de Harvard BioRobotics Laboratory. ABSTRACT When we interact with the environment in our daily life (using a toothbrush, opening doors, using cell-phones, etc.), or in professional situations (medical interventions, manufacturing processes, etc.) we typically perform dexterous manipulations that involve multiple fingers and palm for both hands. Therefore, multi-Finger haptic methods can provide a realistic and natural human-machine interface to enhance immersion when interacting with simulated or remote environments. Most commercial devices allow haptic interaction with only one contact point, which may be sufficient for some exploration or palpation tasks but are not enough to perform advanced object manipulations such as grasping. In this thesis, I investigate the mechanical design, control and applications of a modular haptic device that can provide force feedback to the index, thumb and middle fingers of the user. The designed mechanical device is optimized with a multi-objective design function to achieve a low inertia, a large workspace, manipulability, and force-feedback of up to 3 N within the workspace; the bandwidth and rigidity for the device is assessed through simulation and real experimentation. One of the most important areas when designing haptic devices is the end-effector, since it is in contact with the user. In this thesis the design and evaluation of a thimble-like, lightweight, user-adaptable, and cost-effective device that incorporates four contact force sensors is described. This design allows estimation of the forces applied by a user during manipulation of virtual and real objects. The design of a real-time, modular control architecture for multi-finger haptic interaction is described. Requirements for control of multi-finger haptic devices are explored. Moreover, a large number of signals have to be acquired, processed, sent over the network and mathematical computations such as device direct and inverse kinematics, jacobian, grasp detection algorithms, etc. have to be calculated in Real Time to assure the required high fidelity for the haptic interaction. The Hardware control architecture has different modules and consists of an FPGA for the low-level controller and a RT controller for managing all the complex calculations (jacobian, kinematics, etc.); this provides a compact and scalable solution for the required high computation capabilities assuring a correct frequency rate for the control loop of 1 kHz. A set-up for dexterous virtual and real manipulation is described. Moreover, a new algorithm named the iterative kinematic decoupling method was implemented to solve the inverse kinematics of a robotic manipulator. In order to understand the importance of multi-modal interaction including haptics, a subject study was carried out to look for sensory stimuli that correlate with fast response time and enhanced accuracy. This experiment was carried out in collaboration with neuro-scientists from Technion Israel Institute of Technology. By comparing the grasping response times in unimodal (auditory, visual, and haptic) events with the response times in events with bimodal and trimodal combinations. It is concluded that in grasping tasks the synchronized motion of the fingers to generate the grasping response relies on haptic cues. This processing-speed advantage of haptic cues suggests that multimodalhaptic virtual environments are superior in generating motor contingencies, enhancing the plausibility of events. Applications that include haptics provide users with more time at the cognitive stages to fill in missing information creatively and form a richer experience. A major application of haptic devices is the design of new simulators to train manual skills for the medical sector. In collaboration with physical therapists from Griffith University in Australia, we developed a simulator to allow hand rehabilitation manipulations. First, the non-linear stiffness properties of the metacarpophalangeal joint of the index finger were estimated by using the designed end-effector; these parameters are implemented in a scenario that simulates the behavior of the human hand and that allows haptic interaction through the designed haptic device. The potential application of this work is related to educational and medical training purposes. In this thesis, new methods to simultaneously control the position and orientation of a robotic manipulator and the grasp of a robotic hand when interacting with large real environments are studied. The reachable workspace is extended by automatically switching between rate and position control modes. Moreover, the human hand gesture is recognized by reading the relative movements of the index, thumb and middle fingers of the user during the early stages of the approximation-to-the-object phase and then mapped to the robotic hand actuators. These methods are validated to perform dexterous manipulation of objects with a robotic manipulator, and different robotic hands. This work is the result of a research collaboration with researchers from the Harvard BioRobotics Laboratory. The developed experiments show that the overall task time is reduced and that the developed methods allow for full dexterity and correct completion of dexterous manipulations.

Simulation-based evaluation of susceptibility distortion correction methods in diffusion MRI for connectivity analysis

Connectivity analysis on diffusion MRI data of the whole-brain suffers from distortions caused by the standard echo-planar imaging acquisition strategies. These images show characteristic geometrical deformations and signal destruction that are an important drawback limiting the success of tractography algorithms. Several retrospective correction techniques are readily available. In this work, we use a digital phantom designed for the evaluation of connectivity pipelines. We subject the phantom to a ���theoretically correct��� and plausible deformation that resembles the artifact under investigation. We correct data back, with three standard methodologies (namely fieldmap-based, reversed encoding-based, and registration- based). Finally, we rank the methods based on their geometrical accuracy, the dropout compensation, and their impact on the resulting connectivity matrices.

Systems and technologies for objective evaluation of technical skills in laparoscopic surgery

Minimally invasive surgery is a highly demanding surgical approach regarding technical requirements for the surgeon, who must be trained in order to perform a safe surgical intervention. Traditional surgical education in minimally invasive surgery is commonly based on subjective criteria to quantify and evaluate surgical abilities, which could be potentially unsafe for the patient. Authors, surgeons and associations are increasingly demanding the development of more objective assessment tools that can accredit surgeons as technically competent. This paper describes the state of the art in objective assessment methods of surgical skills. It gives an overview on assessment systems based on structured checklists and rating scales, surgical simulators, and instrument motion analysis. As a future work, an objective and automatic assessment method of surgical skills should be standardized as a means towards proficiency-based curricula for training in laparoscopic surgery and its certification.

Multi-dimensional classification with super-classes

The multi-dimensional classification problem is a generalisation of the recently-popularised task of multi-label classification, where each data instance is associated with multiple class variables. There has been relatively little research carried out specific to multi-dimensional classification and, although one of the core goals is similar (modelling dependencies among classes), there are important differences; namely a higher number of possible classifications. In this paper we present method for multi-dimensional classification, drawing from the most relevant multi-label research, and combining it with important novel developments. Using a fast method to model the conditional dependence between class variables, we form super-class partitions and use them to build multi-dimensional learners, learning each super-class as an ordinary class, and thus explicitly modelling class dependencies. Additionally, we present a mechanism to deal with the many class values inherent to super-classes, and thus make learning efficient. To investigate the effectiveness of this approach we carry out an empirical evaluation on a range of multi-dimensional datasets, under different evaluation metrics, and in comparison with high-performing existing multi-dimensional approaches from the literature. Analysis of results shows that our approach offers important performance gains over competing methods, while also exhibiting tractable running time.

Supporting patient screening to identify suitable clinical trials.

To support the efficient execution of post-genomic multi-centric clinical trials in breast cancer we propose a solution that streamlines the assessment of the eligibility of patients for available trials. The assessment of the eligibility of a patient for a trial requires evaluating whether each eligibility criterion is satisfied and is often a time consuming and manual task. The main focus in the literature has been on proposing different methods for modelling and formalizing the eligibility criteria. However the current adoption of these approaches in clinical care is limited. Less effort has been dedicated to the automatic matching of criteria to the patient data managed in clinical care. We address both aspects and propose a scalable, efficient and pragmatic patient screening solution enabling automatic evaluation of eligibility of patients for a relevant set of trials. This covers the flexible formalization of criteria and of other relevant trial metadata and the efficient management of these representations.

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.

Optimization and evaluation in space conditions of multi-GHz optical modulators

Among the different optical modulator technologies available such as polymer, III-V semiconductors, Silicon, the well-known Lithium Niobate (LN) offers the best trade-off in terms of performances, ease of use, and power handling capability [1-9]. The LN technology is still widely deployed within the current high data rate fibre optic communications networks. This technology is also the most mature and guarantees the reliability which is required for space applications [9].In or der to fulfil the target specifications of opto-microwave payloads, an optimization of the design of a Mach-Zehnder (MZ) modulator working at the 1500nm telecom wavelength was performed in the frame of the ESA-ARTES "Multi GigaHertz Optical Modulator" (MGOM) project in order to reach ultra-low optical insertion loss and low effective driving voltage in the Ka band. The selected modulator configuration was the X-cut crystal orientation, associated to high stability Titanium in-diffusion process for the optical waveguide. Starting from an initial modulator configuration exhibiting 9 V drive voltage @ 30 GHz, a complete redesign of the coplanar microwave electrodes was carried out in order to reach a 6 V drive voltage @ 30GHz version. This redesign was associated to an optimization of the interaction between the optical waveguide and the electrodes. Following the optimisation steps, an evaluation program was applied on a lot of 8 identical modulators. A full characterisation was carried out to compare performances, showing small variations between the initial and final functional characteristics. In parallel, two similar modulators were submitted to both gamma (10-100 krad) and proton irradiation (10.109 p/cm��) with minor performance degradation.

Evaluation of configurations of supply networks supported by it systems

Los sistemas transaccionales tales como los programas inform��ticos para la planificaci��n de recursos empresariales (ERP software) se han implementado ampliamente mientras que los sistemas anal��ticos para la gesti��n de la cadena de suministro (SCM software) no han tenido el ��xito deseado por la industria de tecnolog��a de informaci��n (TI). Aunque se documentan beneficios importantes derivados de las implantaciones de SCM software, las empresas industriales son reacias a invertir en este tipo de sistemas. Por una parte esto es debido a la falta de m��todos que son capaces de detectar los beneficios por emplear esos sistemas, y por otra parte porque el coste asociado no est�� identificado, detallado y cuantificado suficientemente. Los esquemas de coordinaci��n basados ��nicamente en sistemas ERP son alternativas v��lidas en la pr��ctica industrial siempre que la relaci��n coste-beneficio esta favorable. Por lo tanto, la evaluaci��n de formas organizativas teniendo en cuenta expl��citamente el coste debido a procesos administrativos, en particular por ciclos iterativos, es de gran inter��s para la toma de decisiones en el ��mbito de inversiones en TI. Con el fin de cerrar la brecha, el prop��sito de esta investigaci��n es proporcionar m��todos de evaluaci��n que permitan la comparaci��n de diferentes formas de organizaci��n y niveles de soporte por sistemas inform��ticos. La tesis proporciona una amplia introducci��n, analizando los retos a los que se enfrenta la industria. Concluye con las necesidades de la industria de SCM software: unas herramientas que facilitan la evaluaci��n integral de diferentes propuestas de organizaci��n. A continuaci��n, la terminolog��a clave se detalla centr��ndose en la teor��a de la organizaci��n, las peculiaridades de inversi��n en TI y la tipolog��a de software de gesti��n de la cadena de suministro. La revisi��n de la literatura clasifica las contribuciones recientes sobre la gesti��n de la cadena de suministro, tratando ambos conceptos, el dise��o de la organizaci��n y su soporte por las TI. La clasificaci��n incluye criterios relacionados con la metodolog��a de la investigaci��n y su contenido. Los estudios emp��ricos en el ��mbito de la administraci��n de empresas se centran en tipolog��as de redes industriales. Nuevos algoritmos de planificaci��n y esquemas de coordinaci��n innovadoras se desarrollan principalmente en el campo de la investigaci��n de operaciones con el fin de proponer nuevas funciones de software. Art��culos procedentes del ��rea de la gesti��n de la producci��n se centran en el an��lisis de coste y beneficio de las implantaciones de sistemas. La revisi��n de la literatura revela que el ��xito de las TI para la coordinaci��n de redes industriales depende en gran medida de caracter��sticas de tres dimensiones: la configuraci��n de la red industrial, los esquemas de coordinaci��n y las funcionalidades del software. La literatura disponible est�� enfocada sobre todo en los beneficios de las implantaciones de SCM software. Sin embargo, la coordinaci��n de la cadena de suministro, bas��ndose en el sistema ERP, sigue siendo la pr��ctica industrial generalizada, pero el coste de coordinaci��n asociado no ha sido abordado por los investigadores. Los fundamentos de dise��o organizativo eficiente se explican en detalle en la medida necesaria para la comprensi��n de la s��ntesis de las diferentes formas de organizaci��n. Se han generado varios esquemas de coordinaci��n variando los siguientes par��metros de dise��o: la estructura organizativa, los mecanismos de coordinaci��n y el soporte por TI. Las diferentes propuestas de organizaci��n desarrolladas son evaluadas por un m��todo heur��stico y otro basado en la simulaci��n por eventos discretos. Para ambos m��todos, se tienen en cuenta los principios de la teor��a de la organizaci��n. La falta de rendimiento empresarial se debe a las dependencias entre actividades que no se gestionan adecuadamente. Dentro del m��todo heur��stico, se clasifican las dependencias y se mide su intensidad bas��ndose en factores contextuales. A continuaci��n, se valora la idoneidad de cada elemento de dise��o organizativo para cada dependencia espec��fica. Por ��ltimo, cada forma de organizaci��n se eval��a bas��ndose en la contribuci��n de los elementos de dise��o tanto al beneficio como al coste. El beneficio de coordinaci��n se refiere a la mejora en el rendimiento log��stico - este concepto es el objeto central en la mayor��a de modelos de evaluaci��n de la gesti��n de la cadena de suministro. Por el contrario, el coste de coordinaci��n que se debe incurrir para lograr beneficios no se suele considerar en detalle. Procesos iterativos son costosos si se ejecutan manualmente. Este es el caso cuando SCM software no est�� implementada y el sistema ERP es el ��nico instrumento de coordinaci��n disponible. El modelo heur��stico proporciona un procedimiento simplificado para la clasificaci��n sistem��tica de las dependencias, la cuantificaci��n de los factores de influencia y la identificaci��n de configuraciones que indican el uso de formas organizativas y de soporte de TI m��s o menos complejas. La simulaci��n de eventos discretos se aplica en el segundo modelo de evaluaci��n utilizando el paquete de software ���Plant Simulation���. Con respecto al rendimiento log��stico, por un lado se mide el coste de fabricaci��n, de inventario y de transporte y las penalizaciones por p��rdida de ventas. Por otro lado, se cuantifica expl��citamente el coste de la coordinaci��n teniendo en cuenta los ciclos de coordinaci��n iterativos. El m��todo se aplica a una configuraci��n de cadena de suministro ejemplar considerando diversos par��metros. Los resultados de la simulaci��n confirman que, en la mayor��a de los casos, el beneficio aumenta cuando se intensifica la coordinaci��n. Sin embargo, en ciertas situaciones en las que se aplican ciclos de planificaci��n manuales e iterativos el coste de coordinaci��n adicional no siempre conduce a mejor rendimiento log��stico. Estos resultados inesperados no se pueden atribuir a ning��n par��metro particular. La investigaci��n confirma la gran importancia de nuevas dimensiones hasta ahora ignoradas en la evaluaci��n de propuestas organizativas y herramientas de TI. A trav��s del m��todo heur��stico se puede comparar de forma r��pida, pero s��lo aproximada, la eficiencia de diferentes formas de organizaci��n. Por el contrario, el m��todo de simulaci��n es m��s complejo pero da resultados m��s detallados, teniendo en cuenta par��metros espec��ficos del contexto del caso concreto y del dise��o organizativo. ABSTRACT Transactional systems such as Enterprise Resource Planning (ERP) systems have been implemented widely while analytical software like Supply Chain Management (SCM) add-ons are adopted less by manufacturing companies. Although significant benefits are reported stemming from SCM software implementations, companies are reluctant to invest in such systems. On the one hand this is due to the lack of methods that are able to detect benefits from the use of SCM software and on the other hand associated costs are not identified, detailed and quantified sufficiently. Coordination schemes based only on ERP systems are valid alternatives in industrial practice because significant investment in IT can be avoided. Therefore, the evaluation of these coordination procedures, in particular the cost due to iterations, is of high managerial interest and corresponding methods are comprehensive tools for strategic IT decision making. The purpose of this research is to provide evaluation methods that allow the comparison of different organizational forms and software support levels. The research begins with a comprehensive introduction dealing with the business environment that industrial networks are facing and concludes highlighting the challenges for the supply chain software industry. Afterwards, the central terminology is addressed, focusing on organization theory, IT investment peculiarities and supply chain management software typology. The literature review classifies recent supply chain management research referring to organizational design and its software support. The classification encompasses criteria related to research methodology and content. Empirical studies from management science focus on network types and organizational fit. Novel planning algorithms and innovative coordination schemes are developed mostly in the field of operations research in order to propose new software features. Operations and production management researchers realize cost-benefit analysis of IT software implementations. The literature review reveals that the success of software solutions for network coordination depends strongly on the fit of three dimensions: network configuration, coordination scheme and software functionality. Reviewed literature is mostly centered on the benefits of SCM software implementations. However, ERP system based supply chain coordination is still widespread industrial practice but the associated coordination cost has not been addressed by researchers. Fundamentals of efficient organizational design are explained in detail as far as required for the understanding of the synthesis of different organizational forms. Several coordination schemes have been shaped through the variation of the following design parameters: organizational structuring, coordination mechanisms and software support. The different organizational proposals are evaluated using a heuristic approach and a simulation-based method. For both cases, the principles of organization theory are respected. A lack of performance is due to dependencies between activities which are not managed properly. Therefore, within the heuristic method, dependencies are classified and their intensity is measured based on contextual factors. Afterwards the suitability of each organizational design element for the management of a specific dependency is determined. Finally, each organizational form is evaluated based on the contribution of the sum of design elements to coordination benefit and to coordination cost. Coordination benefit refers to improvement in logistic performance ��� this is the core concept of most supply chain evaluation models. Unfortunately, coordination cost which must be incurred to achieve benefits is usually not considered in detail. Iterative processes are costly when manually executed. This is the case when SCM software is not implemented and the ERP system is the only available coordination instrument. The heuristic model provides a simplified procedure for the classification of dependencies, quantification of influence factors and systematic search for adequate organizational forms and IT support. Discrete event simulation is applied in the second evaluation model using the software package ���Plant Simulation���. On the one hand logistic performance is measured by manufacturing, inventory and transportation cost and penalties for lost sales. On the other hand coordination cost is explicitly considered taking into account iterative coordination cycles. The method is applied to an exemplary supply chain configuration considering various parameter settings. The simulation results confirm that, in most cases, benefit increases when coordination is intensified. However, in some situations when manual, iterative planning cycles are applied, additional coordination cost does not always lead to improved logistic performance. These unexpected results cannot be attributed to any particular parameter. The research confirms the great importance of up to now disregarded dimensions when evaluating SCM concepts and IT tools. The heuristic method provides a quick, but only approximate comparison of coordination efficiency for different organizational forms. In contrast, the more complex simulation method delivers detailed results taking into consideration specific parameter settings of network context and organizational design.

Methods for the analysis of multi-scale cell dynamics from fluorescence microscopy images

La embriog��nesis es el proceso mediante el cual una c��lula se convierte en un ser un vivo. A lo largo de diferentes etapas de desarrollo, la poblaci��n de c��lulas va proliferando a la vez que el embri��n va tomando forma y se configura. Esto es posible gracias a la acci��n de varios procesos gen��ticos, bioqu��micos y mec��nicos que interaccionan y se regulan entre ellos formando un sistema complejo que se organiza a diferentes escalas espaciales y temporales. Este proceso ocurre de manera robusta y reproducible, pero tambi��n con cierta variabilidad que permite la diversidad de individuos de una misma especie. La aparici��n de la microscop��a de fluorescencia, posible gracias a prote��nas fluorescentes que pueden ser adheridas a las cadenas de expresi��n de las c��lulas, y los avances en la f��sica ��ptica de los microscopios han permitido observar este proceso de embriog��nesis in-vivo y generar secuencias de im��genes tridimensionales de alta resoluci��n espacio-temporal. Estas im��genes permiten el estudio de los procesos de desarrollo embrionario con t��cnicas de an��lisis de imagen y de datos, reconstruyendo dichos procesos para crear la representaci��n de un embri��n digital. Una de las m��s actuales problem��ticas en este campo es entender los procesos mec��nicos, de manera aislada y en interacci��n con otros factores como la expresi��n gen��tica, para que el embri��n se desarrolle. Debido a la complejidad de estos procesos, estos problemas se afrontan mediante diferentes t��cnicas y escalas espec��ficas donde, a trav��s de experimentos, pueden hacerse y confrontarse hip��tesis, obteniendo conclusiones sobre el funcionamiento de los mecanismos estudiados. Esta tesis doctoral se ha enfocado sobre esta problem��tica intentando mejorar las metodolog��as del estado del arte y con un objetivo espec��fico: estudiar patrones de deformaci��n que emergen del movimiento organizado de las c��lulas durante diferentes estados del desarrollo del embri��n, de manera global o en tejidos concretos. Estudios se han centrado en la mec��nica en relaci��n con procesos de se��alizaci��n o interacciones a nivel celular o de tejido. En este trabajo, se propone un esquema para generalizar el estudio del movimiento y las interacciones mec��nicas que se desprenden del mismo a diferentes escalas espaciales y temporales. Esto permitir��a no s��lo estudios locales, si no estudios sistem��ticos de las escalas de interacci��n mec��nica dentro de un embri��n. Por tanto, el esquema propuesto obvia las causas de generaci��n de movimiento (fuerzas) y se centra en la cuantificaci��n de la cinem��tica (deformaci��n y esfuerzos) a partir de im��genes de forma no invasiva. Hoy en d��a las dificultades experimentales y metodol��gicas y la complejidad de los sistemas biol��gicos impiden una descripci��n mec��nica completa de manera sistem��tica. Sin embargo, patrones de deformaci��n muestran el resultado de diferentes factores mec��nicos en interacci��n con otros elementos dando lugar a una organizaci��n mec��nica, necesaria para el desarrollo, que puede ser cuantificado a partir de la metodolog��a propuesta en esta tesis. La metodolog��a asume un medio continuo descrito de forma Lagrangiana (en funci��n de las trayectorias de puntos materiales que se mueven en el sistema en lugar de puntos espaciales) de la din��mica del movimiento, estimado a partir de las im��genes mediante m��todos de seguimiento de c��lulas o de t��cnicas de registro de imagen. Gracias a este esquema es posible describir la deformaci��n instant��nea y acumulada respecto a un estado inicial para cualquier dominio del embri��n. La aplicaci��n de esta metodolog��a a im��genes 3D + t del pez zebra sirvi�� para desvelar estructuras mec��nicas que tienden a estabilizarse a lo largo del tiempo en dicho embri��n, y que se organizan a una escala semejante al del mapa de diferenciaci��n celular y con indicios de correlaci��n con patrones de expresi��n gen��tica. Tambi��n se aplic�� la metodolog��a al estudio del tejido amnioserosa de la Drosophila (mosca de la fruta) durante el cierre dorsal, obteniendo indicios de un acoplamiento entre escalas subcelulares, celulares y supracelulares, que genera patrones complejos en respuesta a la fuerza generada por los esqueletos de acto-myosina. En definitiva, esta tesis doctoral propone una estrategia novedosa de an��lisis de la din��mica celular multi-escala que permite cuantificar patrones de manera inmediata y que adem��s ofrece una representaci��n que reconstruye la evoluci��n de los procesos como los ven las c��lulas, en lugar de como son observados desde el microscopio. Esta metodolog��a por tanto permite nuevas formas de an��lisis y comparaci��n de embriones y tejidos durante la embriog��nesis a partir de im��genes in-vivo. ABSTRACT The embryogenesis is the process from which a single cell turns into a living organism. Through several stages of development, the cell population proliferates at the same time the embryo shapes and the organs develop gaining their functionality. This is possible through genetic, biochemical and mechanical factors that are involved in a complex interaction of processes organized in different levels and in different spatio-temporal scales. The embryogenesis, through this complexity, develops in a robust and reproducible way, but allowing variability that makes possible the diversity of living specimens. The advances in physics of microscopes and the appearance of fluorescent proteins that can be attached to expression chains, reporting about structural and functional elements of the cell, have enabled for the in-vivo observation of embryogenesis. The imaging process results in sequences of high spatio-temporal resolution 3D+time data of the embryogenesis as a digital representation of the embryos that can be further analyzed, provided new image processing and data analysis techniques are developed. One of the most relevant and challenging lines of research in the field is the quantification of the mechanical factors and processes involved in the shaping process of the embryo and their interactions with other embryogenesis factors such as genetics. Due to the complexity of the processes, studies have focused on specific problems and scales controlled in the experiments, posing and testing hypothesis to gain new biological insight. However, methodologies are often difficult to be exported to study other biological phenomena or specimens. This PhD Thesis is framed within this paradigm of research and tries to propose a systematic methodology to quantify the emergent deformation patterns from the motion estimated in in-vivo images of embryogenesis. Thanks to this strategy it would be possible to quantify not only local mechanisms, but to discover and characterize the scales of mechanical organization within the embryo. The framework focuses on the quantification of the motion kinematics (deformation and strains), neglecting the causes of the motion (forces), from images in a non-invasive way. Experimental and methodological challenges hamper the quantification of exerted forces and the mechanical properties of tissues. However, a descriptive framework of deformation patterns provides valuable insight about the organization and scales of the mechanical interactions, along the embryo development. Such a characterization would help to improve mechanical models and progressively understand the complexity of embryogenesis. This framework relies on a Lagrangian representation of the cell dynamics system based on the trajectories of points moving along the deformation. This approach of analysis enables the reconstruction of the mechanical patterning as experienced by the cells and tissues. Thus, we can build temporal profiles of deformation along stages of development, comprising both the instantaneous events and the cumulative deformation history. The application of this framework to 3D + time data of zebrafish embryogenesis allowed us to discover mechanical profiles that stabilized through time forming structures that organize in a scale comparable to the map of cell differentiation (fate map), and also suggesting correlation with genetic patterns. The framework was also applied to the analysis of the amnioserosa tissue in the drosophila���s dorsal closure, revealing that the oscillatory contraction triggered by the acto-myosin network organized complexly coupling different scales: local force generation foci, cellular morphology control mechanisms and tissue geometrical constraints. In summary, this PhD Thesis proposes a theoretical framework for the analysis of multi-scale cell dynamics that enables to quantify automatically mechanical patterns and also offers a new representation of the embryo dynamics as experienced by cells instead of how the microscope captures instantaneously the processes. Therefore, this framework enables for new strategies of quantitative analysis and comparison between embryos and tissues during embryogenesis from in-vivo images.

M��todos diferenciales e interferom��tricos para la evaluaci��n de deformaciones de la corteza terrestre mediante t��cnicas GNSS e InSAR = Differential and interferometric methods for evaluation of crustal deformation using GNSS and InSAR techniques

La actividad volc��nica interviene en multitud de facetas de la propia actividad humana, no siempre negativas. Sin embargo, son m��s los motivos de peligrosidad y riesgo que incitan al estudio de la actividad volc��nica. Existen razones de seguridad que inciden en el mantenimiento del seguimiento y monitorizaci��n de la actividad volc��nica para garantizar la vida y la seguridad de los asentamientos antr��picos en las proximidades de los edificios volc��nicos. En esta tesis se define e implementa un sistema de monitorizaci��n de movimientos de la corteza en las islas de Tenerife y La Palma, donde el impacto social que representa un aumento o variaci��n de la actividad volc��nica en las islas es muy severo. Aparte de la alta densidad demogr��fica del Archipi��lago, esta poblaci��n aumenta significativamente, en diferentes periodos a lo largo del a��o, debido a la actividad tur��stica que representa la mayor fuente de ingresos de las islas. La poblaci��n y los centros tur��sticos se diseminan predominantemente a lo largo de las costas y tambi��n a lo largo de los flancos de los edificios volc��nicos. Quiz�� el mantenimiento de estas estructuras sociales y socio-econ��micas son los motivos m��s importantes que justifican una monitorizaci��n de la actividad volc��nica en las Islas Canarias. Recientemente se ha venido trabajando cada vez m��s en el intento de predecir la actividad volc��nica utilizando los nuevos sistemas de monitorizaci��n geod��sica, puesto que la actividad volc��nica se manifiesta anteriormente por deformaci��n de la corteza terrestre y cambios en la fuerza de la gravedad en la zona donde m��s tarde se registran eventos volc��nicos. Los nuevos dispositivos y sensores que se han desarrollado en los ��ltimos a��os en materias como la geodesia, la observaci��n de la Tierra desde el espacio y el posicionamiento por sat��lite, han permitido observar y medir tanto la deformaci��n producida en el terreno como los cambios de la fuerza de la gravedad antes, durante y posteriormente a los eventos volc��nicos que se producen. Estos nuevos dispositivos y sensores han cambiado las t��cnicas o metodolog��as geod��sicas que se ven��an utilizando hasta la aparici��n de los mismos, renovando m��todos cl��sicos y desarrollando otros nuevos que ya se est��n afianzando como metodolog��as probadas y reconocidas para ser usadas en la monitorizaci��n volc��nica. Desde finales de la d��cada de los noventa del siglo pasado se han venido desarrollando en las Islas Canarias varios proyectos que han tenido como objetivos principales el desarrollo de nuevas t��cnicas de observaci��n y monitorizaci��n por un lado y el dise��o de una metodolog��a de monitorizaci��n volc��nica adecuada, por otro. Se presenta aqu�� el estudio y desarrollo de t��cnicas GNSS para la monitorizaci��n de deformaciones corticales y su campo de velocidades para las islas de Tenerife y La Palma. En su implementaci��n, se ha tenido en cuenta el uso de la infraestructura geod��sica y de monitorizaci��n existente en el archipi��lago a fin de optimizar costes, adem��s de complementarla con nuevas estaciones para dar una cobertura total a las dos islas. Los resultados obtenidos en los proyectos, que se describen en esta memoria, han dado nuevas perspectivas en la monitorizaci��n geod��sica de la actividad volc��nica y nuevas zonas de inter��s que anteriormente no se conoc��an en el entorno de las Islas Canarias. Se ha tenido especial cuidado en el tratamiento y propagaci��n de los errores durante todo el proceso de observaci��n, medida y proceso de los datos registrados, todo ello en aras de cuantificar el grado de fiabilidad de los resultados obtenidos. Tambi��n en este sentido, los resultados obtenidos han sido verificados con otros procedentes de sistemas de observaci��n radar de sat��lite, incorporando adem��s a este estudio las implicaciones que el uso conjunto de tecnolog��as radar y GNSS tendr��n en un futuro en la monitorizaci��n de deformaciones de la corteza terrestre. ABSTRACT Volcanic activity occurs in many aspects of human activity, and not always in a negative manner. Nonetheless, research into volcanic activity is more likely to be motivated by its danger and risk. There are security reasons that influence the monitoring of volcanic activity in order to guarantee the life and safety of human settlements near volcanic edifices. This thesis defines and implements a monitoring system of movements in the Earth���s crust in the islands of Tenerife and La Palma, where the social impact of an increase (or variation) of volcanic activity is very severe. Aside from the high demographic density of the archipelago, the population increases significantly in different periods throughout the year due to tourism, which represents a major source of revenue for the islands. The population and the tourist centres are mainly spread along the coasts and also along the flanks of the volcanic edifices. Perhaps the preservation of these social and socio-economic structures is the most important reason that justifies monitoring volcanic activity in the Canary Islands. Recently more and more work has been done with the intention of predicting volcanic activity, using new geodesic monitoring systems, since volcanic activity is evident prior to eruption because of a deformation of the Earth���s crust and changes in the force of gravity in the zone where volcanic events will later be recorded. The new devices and sensors that have been developed in recent years in areas such as geodesy, the observation of the Earth from space, and satellite positioning have allowed us to observe and measure the deformation produced in the Earth as well as the changes in the force of gravity before, during, and after the volcanic events occur. The new devices and sensors have changed the geodetic techniques and methodologies that were used previously. The classic methods have been renovated and other newer ones developed that are now vouched for as proven recognised methodologies to be used for volcanic monitoring. Since the end of the 1990s, in the Canary Islands various projects have been developed whose principal aim has been the development of new observation and monitoring techniques on the one hand, and the design of an appropriate volcanic monitoring methodology on the other. The study and development of GNSS techniques for the monitoring of crustal deformations and their velocity field is presented here. To carry out the study, the use of geodetic infrastructure and existing monitoring in the archipelago have been taken into account in order to optimise costs, besides complementing it with new stations for total coverage on both islands. The results obtained in the projects, which are described below, have produced new perspectives in the geodetic monitoring of volcanic activity and new zones of interest which previously were unknown in the environment of the Canary Islands. Special care has been taken with the treatment and propagation of errors during the entire process of observing, measuring, and processing the recorded data. All of this was done in order to quantify the degree of trustworthiness of the results obtained. Also in this sense, the results obtained have been verified with others from satellite radar observation systems, incorporating as well in this study the implications that the joint use of radar technologies and GNSS will have for the future of monitoring deformations in the Earth���s crust.

Multi-component assessment of chronic obstructive pulmonary disease : an evaluation of the ADO and DOSE indices and the global obstructive lung disease categories in international primary care data sets

Funding The International Primary Care Respiratory Group (IPCRG) provided funding for this research project as an UNLOCK group study for which the funding was obtained through an unrestricted grant by Novartis AG, Basel, Switzerland. The latter funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. Database access for the OPCRD was provided by the Respiratory Effectiveness Group (REG) and Research in Real Life; the OPCRD statistical analysis was funded by REG. The Bocholtz Study was funded by PICASSO for COPD, an initiative of Boehringer Ingelheim, Pfizer and the Caphri Research Institute, Maastricht University, The Netherlands.

Applying logic forms and statistical methods to CL-SR performance

This paper describes a CL-SR system that employs two different techniques: the first one is based on NLP rules that consist on applying logic forms to the topic processing while the second one basically consists on applying the IR-n statistical search engine to the spoken document collection. The application of logic forms to the topics allows to increase the weight of topic terms according to a set of syntactic rules. Thus, the weights of the topic terms are used by IR-n system in the information retrieval process.

Evaluation of the multi-element capabilities of collision/reaction cell inductively coupled plasma - mass spectrometry in wine analysis

This work explores the multi-element capabilities of inductively coupled plasma - mass spectrometry with collision/reaction cell technology (CCT-ICP-MS) for the simultaneous determination of both spectrally interfered and non-interfered nuclides in wine samples using a single set of experimental conditions. The influence of the cell gas type (i.e. He, He+H2 and He+NH3), cell gas flow rate and sample pre-treatment (i.e. water dilution or acid digestion) on the background-equivalent concentration (BEC) of several nuclides covering the mass range from 7 to 238 u has been studied. Results obtained in this work show that, operating the collision/reaction cell with a compromise cell gas flow rate (i.e. 4 mL min���1) improves BEC values for interfered nuclides without a significant effect on the BECs for non-interfered nuclides, with the exception of the light elements Li and Be. Among the different cell gas mixtures tested, the use of He or He+H2 is preferred over He+NH3 because NH3 generates new spectral interferences. No significant influence of the sample pre-treatment methodology (i.e. dilution or digestion) on the multi-element capabilities of CCT-ICP-MS in the context of simultaneous analysis of interfered and non-interfered nuclides was observed. Nonetheless, sample dilution should be kept at minimum to ensure that light nuclides (e.g. Li and Be) could be quantified in wine. Finally, a direct 5-fold aqueous dilution is recommended for the simultaneous trace and ultra-trace determination of spectrally interfered and non-interfered elements in wine by means of CCT-ICP-MS. The use of the CCT is mandatory for interference-free ultra-trace determination of Ti and Cr. Only Be could not be determined when using the CCT due to a deteriorated limit of detection when compared to conventional ICP-MS.