13 resultados para NESSIE SAFER
em Universidad Politécnica de Madrid
Resumo:
An important goal in the field of intelligent transportation systems (ITS) is to provide driving aids aimed at preventing accidents and reducing the number of traffic victims. The commonest traffic accidents in urban areas are due to sudden braking that demands a very fast response on the part of drivers. Attempts to solve this problem have motivated many ITS advances including the detection of the intention of surrounding cars using lasers, radars or cameras. However, this might not be enough to increase safety when there is a danger of collision. Vehicle to vehicle communications are needed to ensure that the other intentions of cars are also available. The article describes the development of a controller to perform an emergency stop via an electro-hydraulic braking system employed on dry asphalt. An original V2V communication scheme based on WiFi cards has been used for broadcasting positioning information to other vehicles. The reliability of the scheme has been theoretically analyzed to estimate its performance when the number of vehicles involved is much higher. This controller has been incorporated into the AUTOPIA program control for automatic cars. The system has been implemented in Citron C3 Pluriel, and various tests were performed to evaluate its operation.
Resumo:
Background: Minimally invasive surgery creates two technological opportunities: (1) the development of better training and objective evaluation environments, and (2) the creation of image guided surgical systems.
Resumo:
Finding adequate materials to withstand the demanding conditions in the future fusion and fission reactors is a real challenge in the development of these technologies. Structural materials need to sustain high irradiation doses and temperatures that will change the microstructure over time. A better understanding of the changes produced by the irradiation will allow for a better choice of materials, ensuring a safer and reliable future power plants. High-Cr ferritic/martensitic steels head the list of structural materials due to their high resistance to swelling and corrosion. However, it is well known that these alloys present a problem of embrittlement, which could be caused by the presence of defects created by irradiation as these defects act as obstacles for dislocation motion. Therefore, the mechanical response of these materials will depend on the type of defects created during irradiation. In this work, we address a study of the effect Cr concentration has on single interstitial defect formation energies in FeCr alloys.
Resumo:
Training and assessment paradigms for laparoscopic surgical skills are evolving from traditional mentortrainee tutorship towards structured, more objective and safer programs. Accreditation of surgeons requires reaching a consensus on metrics and tasks used to assess surgeons psychomotor skills. Ongoing development of tracking systems and software solutions has allowed for the expansion of novel training and assessment means in laparoscopy. The current challenge is to adapt and include these systems within training programs, and to exploit their possibilities for evaluation purposes. This paper describes the state of the art in research on measuring and assessing psychomotor laparoscopic skills. It gives an overview on tracking systems as well as on metrics and advanced statistical and machine learning techniques employed for evaluation purposes. The later ones have a potential to be used as an aid in deciding on the surgical competence level, which is an important aspect when accreditation of the surgeons in particular, and patient safety in general, are considered. The prospective of these methods and tools make them complementary means for surgical assessment of motor skills, especially in the early stages of training. Successful examples such as the Fundamentals of Laparoscopic Surgery should help drive a paradigm change to structured curricula based on objective parameters. These may improve the accreditation of new surgeons, as well as optimize their already overloaded training schedules.
Resumo:
Automatic analysis of minimally invasive surgical (MIS) video has the potential to drive new solutions that alleviate existing needs for safer surgeries: reproducible training programs, objective and transparent assessment systems and navigation tools to assist surgeons and improve patient safety. As an unobtrusive, always available source of information in the operating room (OR), this research proposes the use of surgical video for extracting useful information during surgical operations. Methodology proposed includes tools' tracking algorithm and 3D reconstruction of the surgical field. The motivation for these solutions is the augmentation of the laparoscopic view in order to provide orientation aids, optimal surgical path visualization, or preoperative virtual models overlay
Resumo:
Fresh-cut or minimally processed fruit and vegetables have been physically modified from its original form (by peeling, trimming, washing and cutting) to obtain a 100% edible product that is subsequently packaged (usually under modified atmosphere packaging MAP) and kept in refrigerated storage. In fresh-cut products, physiological activity and microbiological spoilage, determine their deterioration and shelf-life. The major preservation techniques applied to delay spoilage are chilling storage and MAP, combined with chemical treatments antimicrobial solutions antibrowning, acidulants, antioxidants, etc.). The industry looks for safer alternatives. Consequently, the sector is asking for innovative, fast, cheap and objective techniques to evaluate the overall quality and safety of fresh-cut products in order to obtain decision tools for implementing new packaging materials and procedures. In recent years, hyperspectral imaging technique has been regarded as a tool for analyses conducted for quality evaluation of food products in research, control and industries. The hyperspectral imaging system allows integrating spectroscopic and imaging techniques to enable direct identification of different components or quality characteristics and their spatial distribution in the tested sample. The objective of this work is to develop hyperspectral image processing methods for the supervision through plastic films of changes related to quality deterioration in packed readyto-use leafy vegetables during shelf life. The evolutions of ready-to-use spinach and watercress samples covered with three different common transparent plastic films were studied. Samples were stored at 4 C during the monitoring period (until 21 days). More than 60 hyperspectral images (from 400 to 1000 nm) per species were analyzed using ad hoc routines and commercial toolboxes of MatLab. Besides common spectral treatments for removing additive and multiplicative effects, additional correction, previously to any other correction, was performed in the images of leaves in order to avoid the modification in their spectra due to the presence of the plastic transparent film. Findings from this study suggest that the developed images analysis system is able to deal with the effects caused in the images by the presence of plastic films in the supervision of shelf-life in leafy vegetables, in which different stages of quality has been identified.
Resumo:
In tunnel construction, as in every engineering work, it is usual the decision making, with incomplete data. Nevertheless, consciously or not, the builder weighs the risks (even if this is done subjectively) so that he can offer a cost. The objective of this paper is to recall the existence of a methodology to treat the uncertainties in the data so that it is possible to see their effect on the output of the computational model used and then to estimate the failure probability or the safety margin of a structure. In this scheme it is possible to include the subjective knowledge on the statistical properties of the random variables and, using a numerical model consistent with the degree of complexity appropiate to the problem at hand, to make rationally based decisions. As will be shown with the method it is possible to quantify the relative importance of the random variables and, in addition, it can be used, under certain conditions, to solve the inverse problem. It is then a method very well suited both to the project and to the control phases of tunnel construction.
Resumo:
Actualmente, la reduccin de materias activas (UE) y la implantacin de la nueva Directiva comunitaria 2009/128/ que establece el marco de actuacin para conseguir un uso sostenible de los plaguicidas qumicos y la preferencia de uso de mtodos biolgicos, fsicos y otros no qumicos, obliga a buscar mtodos de control menos perjudiciales para el medio ambiente. El control biolgico (CB) de enfermedades vegetales empleando agentes de control biolgico (ACB) se percibe como una alternativa ms segura y con menor impacto ambiental, bien solos o bien como parte de una estrategia de control integrado. El aislado 212 de Penicillium oxalicum (PO212) (ATCC 201888) fue aislado originalmente de la micoflora del suelo en Espaa y ha demostrado ser un eficaz ACB frente a la marchitez vascular del tomate. Una vez identificado y caracterizado el ACB se inici el periodo de desarrollo del mismo poniendo a punto un mtodo de produccin en masa de sus conidias. Tras lo cual se inici el proceso de formulacin del ACB deshidratando las conidias para su preservacin durante un perodo de tiempo mayor mediante lecho fluido. Finalmente, se han desarrollado algunos formulados que contienen de forma individual diferentes aditivos que han alargado su viabilidad, estabilidad y facilitado su manejo y aplicacin. Sin embargo, es necesario seguir trabajando en la mejora de su eficacia de biocontrol. El primer objetivo de esta Tesis se ha centrado en el estudio de la interaccin ACB-patgeno-husped que permita la actuacin de P.oxalicum en diferentes patosistemas. Uno de los primeros puntos que se abordan dentro de este objetivo es el desarrollo de nuevas FORMULACIONES del ACB que incrementen su eficacia frente a la marchitez vascular del tomate. Las conidias formuladas de PO212 se obtuvieron por la adicin conjunta de distintos aditivos (mojantes, adherentes o estabilizantes) en dos momentos diferentes del proceso de produccin/secado: i) antes del proceso de produccin (en la bolsa de fermentacin) en el momento de la inoculacin de las bolsas de fermentacin con conidias de PO212 o ii) antes del secado en el momento de la resuspensin de las conidias tras su centrifugacin. De las 22 nuevas formulaciones desarrolladas y evaluadas en plantas de tomate en ensayos en invernadero, seis de ellas (FOR22, FOR25, FOR32, FOR35, FOR36 y FOR37) mejoran significativamente (P=0,05) el control de la marchitez vascular del tomate con respecto al obtenido con las conidias secas de P.oxalicum sin aditivos (CSPO) o con el fungicida Bavistin. Los formulados que mejoran la eficacia de las conidias secas sin aditivos son aquellos que contienen como humectantes alginato sdico en fermentacin, seguido de aquellos que contienen glicerol como estabilizante en fermentacin, y metil celulosa y leche desnatada como adherentes antes del secado. Adems, el control de la marchitez vascular del tomate por parte de los formulados de P. oxalicum est relacionado con la fecha de inicio de la enfermedad. Otra forma de continuar mejorando la eficacia de biocontrol es mejorar la materia activa mediante la SELECCIN DE NUEVAS CEPAS de P. oxalicum, las cuales podran tener diferentes niveles de eficacia. De entre las 28 nuevas cepas de P. oxalicum ensayadas en cmara de cultivo, slo el aislado PO15 muestra el mismo nivel de eficacia que PO212 (62-67% de control) frente a la marchitez vascular del tomate en casos de alta presin de enfermedad. Mientras que, en casos de baja presin de enfermedad todas las cepas de P. oxalicum y sus mezclas demuestran ser eficaces. Finalmente, se estudia ampliar el rango de actuacin de este ACB a OTROS HUSPEDES Y OTROS PATGENOS Y DIFERENTES GRADOS DE VIRULENCIA. En ensayos de eficacia de P. oxalicum frente a aislados de diferente agresividad de Verticillium spp. y Fusarium oxysporum f. sp. lycopersici en plantas de tomate en cmaras de cultivo, se demuestra que la eficacia de PO212 est negativamente correlacionada con el nivel de enfermedad causada por F. oxysporum f. sp. lycopersici pero que no hay ningn efecto diferencial en la reduccin de la incidencia ni de la gravedad segn la virulencia de los aislados. Sin embargo, en los ensayos realizados con V. dahliae, PO212 causa una mayor reduccin de la enfermedad en las plantas inoculadas con aislados de virulencia media. La eficacia de PO212 tambin era mayor frente a aislados de virulencia media alta de F. oxysporum f. sp. melonis y F. oxysporum f. sp. niveum, en plantas de meln y sanda, respectivamente. En ambos huspedes se demuestra que la dosis ptima de aplicacin del ACB es de 107 conidias de PO212 g-1 de suelo de semillero, aplicada 7 das antes del trasplante. Adems, entre 2 y 4 nuevas aplicaciones de PO212 a la races de las plantas mediante un riego al terreno de asiento mejoran la eficacia de biocontrol. La eficacia de PO212 no se limita a hongos patgenos vasculares como los citados anteriormente, sino tambin a otros patgenos como: Phytophthora cactorum, Globodera pallida y G. rostochiensis. PO212 reduce significativamente los sntomas (50%) causados por P. cactorum en plantas de vivero de fresa, tras la aplicacin del ACB por inmersin de las races antes de su trasplante al suelo de viveros comerciales. Por otra parte, la exposicin de los quistes de Globodera pallida y G. rostochiensis (nematodos del quiste de la patata) a las conidias de P. oxalicum, en ensayos in vitro o en microcosmos de suelo, reduce significativamente la capacidad de eclosin de los huevos. Para G. pallida esta reduccin es mayor cuando se emplean exudados de raz de patata del cv. 'Monalisa', que exudados de raz del cv. 'Desire'. No hay una reduccin significativa en la tasa de eclosin con exudados de raz de tomate del cv. 'San Pedro'. Para G. rostochiensis la reduccin en la tasa de eclosin de los huevos se obtiene con exudados de la raz de patata del cv. 'Desire'. El tratamiento con P. oxalicum reduce tambin significativamente el nmero de quistes de G. pallida en macetas. Con el fin de optimizar la aplicacin prctica de P. oxalicum cepa 212 como tratamiento biolgico del suelo, es esencial entender cmo el entorno fsico influye en la capacidad de colonizacin, crecimiento y supervivencia del mismo, as como el posible riesgo que puede suponer su aplicacin sobre el resto de los microorganismos del ecosistema. Por ello en este segundo objetivo de esta tesis se estudia la interaccin del ACB con el medio ambiente en el cual se aplica. Dentro de este objetivo se evala la INFLUENCIA DE LA TEMPERATURA, DISPONIBILIDAD DE AGUA Y PROPIEDADES FSICO-QUMICAS DE LOS SUELOS (POROSIDAD, TEXTURA, DENSIDAD...) SOBRE LA SUPERVIVENCIA Y EL CRECIMIENTO DE PO212 en condiciones controladas elaborando modelos que permitan predecir el impacto de cada factor ambiental en la supervivencia y crecimiento de P. oxalicum y conocer su capacidad para crecer y sobrevivir en diferentes ambientes. En las muestras de suelo se cuantifica: i) la supervivencia de Penicillium spp. usando el recuento del nmero de unidades formadoras de colonias en un medio de cultivo semi-selectivo y ii) el crecimiento (biomasa) de PO212 mediante PCR en tiempo real. En los resultados obtenidos se demuestra que P. oxalicum crece y sobrevive mejor en condiciones de sequa independientemente de la temperatura y del tipo de suelo. Si comparamos tipos de suelo P. oxalicum crece y sobrevive en mayor medida en suelos areno-arcillosos con un bajo contenido en materia orgnica, un mayor pH y una menor disponibilidad de fsforo y nitrgeno. La supervivencia y el crecimiento de P. oxalicum se correlaciona de forma negativa con la disponibilidad de agua y de forma positiva con el contenido de materia orgnica. Slo la supervivencia se correlaciona tambin positivamente con el pH. Por otro lado se realizan ensayos en suelos de huertos comerciales con diferentes propiedades fsico-qumicas y diferentes condiciones ambientales para ESTUDIAR EL ESTABLECIMIENTO, SUPERVIVENCIA Y DISPERSIN VERTICAL Y MOVILIDAD HORIZONTAL DE PO212. P. oxalicum 212 puede persistir y sobrevivir en esos suelos al menos un ao despus de su liberacin pero a niveles similares a los de otras especies de Penicillium indgenas presentes en los mismos suelos naturales. Adems, P. oxalicum 212 muestra una dispersin vertical y movilidad horizontal muy limitada en los diferentes tipos de suelo evaluados. La introduccin de P. oxalicum en un ambiente natural no slo implica su actuacin sobre el microorganismo diana, el patgeno, si no tambin sobre otros microorganismos indgenas. Para EVALUAR EL EFECTO DE LA APLICACIN DE P. oxalicum SOBRE LAS POBLACIONES FNGICAS INDIGENAS PRESENTES EN EL SUELO de dos huertos comerciales, se analizan mediante electroforesis en gradiente desnaturalizante de poliacrilamida (DGGE) muestras de dichos suelos a dos profundidades (5 y 10 cm) y a cuatro fechas desde la aplicacin de P. oxalicum 212 (0, 75, 180 y 365 das). El anlisis de la DGGE muestra que las diferencias entre las poblaciones fngicas se deben significativamente a la fecha de muestreo y son independientes del tratamiento aplicado y de la profundidad a la que se tomen las muestras. Luego, la aplicacin del ACB no afecta a la poblacin fngica de los dos suelos analizados. El anlisis de las secuencias de la DGGE confirma los resultados anteriores y permiten identificar la presencia del ACB en los suelos. La presencia de P. oxalicum en el suelo se encuentra especialmente relacionada con factores ambientales como la humedad. Por tanto, podemos concluir que Penicillium oxalicum cepa 212 puede considerarse un ptimo Agente de Control Biolgico (ACB), puesto que es ecolgicamente competitivo, eficaz para combatir un amplio espectro de enfermedades y no supone un riesgo para el resto de microorganismos fngicos no diana presentes en el lugar de aplicacin. ABSTRACT Currently, reduction of active (EU) and the implementation of the new EU Directive 2009/128 which establishing the framework for action to achieve the sustainable use of chemical pesticides and preference of use of biological, physical and other non-chemical methods, forces to look for control methods less harmful to the environment. Biological control (CB) of plant diseases using biological control agents (BCA) is perceived as a safer alternative and with less environmental impact, either alone or as part of an integrated control strategy. The isolate 212 of Penicillium oxalicum (PO212) (ATCC 201888) was originally isolated from the soil mycoflora in Spain. P. oxalicum is a promising biological control agent for Fusarium wilt and other tomato diseases. Once identified and characterized the BCA, was developed a mass production method of conidia by solid-state fermentation. After determined the process of obtaining a formulated product of the BCA by drying of product by fluid-bed drying, it enables the preservation of the inoculum over a long period of time. Finally, some formulations of dried P. oxalicum conidia have been developed which contain one different additive that have improved their viability, stability and facilitated its handling and application. However, further work is needed to improve biocontrol efficacy. The first objective of this thesis has focused on the study of the interaction BCA- pathogen-host, to allow P.oxalicum to work in different pathosystems. The first point to be addressed in this objective is the development of new FORMULATIONS of BCA which increase their effectiveness against vascular wilt of tomato. PO212 conidial formulations were obtained by the joint addition of various additives (wetting agents, adhesives or stabilizers) at two different points of the production-drying process: i) to substrate in the fermentation bags before the production process, and (ii) to conidial paste obtained after production but before drying. Of the 22 new formulations developed and evaluated in tomato plants in greenhouse tests, six of them (FOR22 , FOR25 , FOR32 , FOR35 , FOR36 and FOR3) improved significantly (P = 0.05) the biocontrol efficacy against tomato wilt with respect to that obtained with dried P.oxalicum conidia without additives (CSPO) or the fungicide Bavistin. The formulations that improve the efficiency of dried conidia without additives are those containing as humectants sodium alginate in the fermentation bags, followed by those containing glycerol as a stabilizer in the fermentation bags, and methylcellulose and skimmed milk as adherents before drying. Moreover, control of vascular wilt of tomatoes by PO212 conidial formulations is related to the date of disease onset. Another way to further improve the effectiveness of biocontrol is to improve the active substance by SELECTION OF NEW STRAINS of P. oxalicum, which may have different levels of effectiveness. Of the 28 new strains of P. oxalicum tested in a culture chamber, only PO15 isolate shows the same effectiveness that PO212 (62-67 % of control) against tomato vascular wilt in cases of high disease pressure. Whereas in cases of low disease pressure all strains of P. oxalicum and its mixtures effective. Finally, we study extend the range of action of this BCA TO OTHER GUESTS AND OTHER PATHOGENS AND DIFFERENT DEGREES OF VIRULENCE. In efficacy trials of P. oxalicum against isolates of different aggressiveness of Verticillium spp. and Fusarium oxysporum f. sp. lycopersici in tomato plants in growth chambers, shows that the efficiency of PO212 is negatively correlated with the level of disease caused by F. oxysporum f. sp. lycopersici. There is not differential effect in reducing the incidence or severity depending on the virulence of isolates. However, PO212 cause a greater reduction of disease in plants inoculated with virulent isolates media of V. dahlia. PO212 efficacy was also higher against isolates of high and average virulence of F. oxysporum f. sp. melonis and F. oxysporum f. sp. niveum in melon and watermelon plants, respectively. In both hosts the optimum dose of the BCA application is 107 conidia PO212 g-1 soil, applied on seedlings 7 days before transplantation into the field. Moreover, the reapplication of PO212 (2-4 times) to the roots by irrigation into the field improve efficiency of biocontrol. The efficacy of PO212 is not limited to vascular pathogens as those mentioned above, but also other pathogens such as Oomycetes (Phytophthora cactorum) and nematodes (Globodera pallida and G. rostochiensis). PO212 significantly reduces symptoms (50 %) caused by P. cactorum in strawberry nursery plants after application of BCA by dipping the roots before transplanting to soil in commercial nurseries. Moreover, the exposure of G. pallida and G. rostochiensis cysts to the conidia of P. oxalicum, in in vitro assays or in soil microcosms significantly reduces hatchability of eggs. The reduction in the rate of G. pallida juveniles hatching was greatest when root diffusates from the `Monalisa potato cultivar were used, followed by root diffusates from the `Dsire potato cultivar. However, no significant reduction in the rate of G. pallida juveniles hatching was found when root diffusates from the San Pedro tomato cultivar were used. For G. rostochiensis reduction in the juveniles hatching is obtained from the root diffusates 'Desire' potato cultivar. Treatment with P. oxalicum also significantly reduces the number of cysts of G. pallida in pots. In order to optimize the practical application of P. oxalicum strain 212 as a biological soil treatment, it is essential to understand how the physical environment influences the BCA colonization, survival and growth, and the possible risk that can cause its application on other microorganisms in the ecosystem of performance. Therefore, the second objective of this thesis is the interaction of the BCA with the environment in which it is applied. Within this objective is evaluated the INFLUENCE OF TEMPERATURE, WATER AVAILABILITY AND PHYSICAL-CHEMICAL PROPERTIES OF SOILS (POROSITY, TEXTURE, DENSITY...) ON SURVIVAL AND GROWTH OF PO212 under controlled conditions to develop models for predicting the environmental impact of each factor on survival and growth of P. oxalicum and to know their ability to grow and survive in different environments. Two parameters are evaluated in the soil samples: i) the survival of Penicillium spp. by counting the number of colony forming units in semi-selective medium and ii) growth (biomass) of PO212 by real-time PCR. P. oxalicum grows and survives better in drought conditions regardless of temperature and soil type. P. oxalicum grows and survives more in sandy loam soils with low organic matter content, higher pH and lower availability of phosphorus and nitrogen. Survival and growth of P. oxalicum negatively correlates with the availability of water and positively with the organic content. Only survival also correlated positively with pH. Moreover, trials are carried out into commercial orchards soils with different physic-chemical properties and different environmental conditions TO STUDY THE ESTABLISHMENT, SURVIVAL, VERTICAL DISPERSION AND HORIZONTAL SPREAD OF PO212. P. oxalicum 212 can persist and survive at very low levels in soil one year after its release. The size of the PO212 population after its release into the tested natural soils is similar to that of indigenous Penicillium spp. Furthermore, the vertical dispersion and horizontal spread of PO212 is limited in different soil types. The introduction of P. oxalicum in a natural environment not only involves their action on the target organism, the pathogen, but also on other indigenous microorganisms. TO ASSESS THE EFFECT OF P. oxalicum APPLICATION ON SOIL INDIGENOUS FUNGAL COMMUNITIES in two commercial orchards, soil samples are analyzed by Denaturing Gradient Gel Electrophoresis polyacrylamide (DGGE). Samples are taken from soil at two depths (5 and 10 cm) and four dates from the application of P. oxalicum 212 (0, 75, 180 and 365 days). DGGE analysis shows that differences are observed between sampling dates and are independent of the treatment of P. oxalicum applied and the depth. BCA application does not affect the fungal population of the two soil analyzed. Sequence analysis of the DGGE bands confirms previous findings and to identify the presence of BCA on soils. The presence of P. oxalicum in soil is especially related to environmental factors such as humidity. Therefore, we conclude that the 212 of strain Penicillium oxalicum can be considered an optimum BCA, since it is environmentally competitive and effective against a broad spectrum of diseases and does not have any negative effect on soil non-target fungi communities.
Resumo:
El siguiente Trabajo Fin de Master se divide en tres partes, siempre, alrededor de la identificacin biomtrica. Esta ciencia aprovecha que existen ciertas caractersticas biolgicas o conductuales singulares e inalterables, por lo que pueden ser analizados y medidos para crear una huella biomtrica. Estas caractersticas son difciles de perder, transferir u olvidar y son perdurables en el tiempo. En la primera de las partes se ofrecer una visin sobre la importancia histrica de esta ciencia, desde los primeros vestigios humanos, en la zona de Mesopotamia, pasando por los grandes innovadores y precursores de la identificacin biomtrica, como Bertillon, Galton, Vucetich, etc. auspiciados por una finalidad mayoritariamente criminalstica o policiaca, hasta la gran revolucin a finales del siglo pasado, en las que tcnicas que parecan ciencia ficcin se hicieron realidad. En el siguiente apartado se analizaran las 6 principales tcnicas que se usan actualmente, realizando una mirada ms profunda en los principios naturales, fisiolgicos y fsicos sobre los que se basan se expondrn las tendencias futuras sobre las que trabajara la industria para el desarrollo de tcnicas ms seguras, menos invasivas y ms transparentes para los usuarios finales. Estas como ha pasado a lo largo de la historia sonaran increbles, pero una vez ms la raza humana conseguir materializarlas e introducirlas en su da a da. Para finalizar y despus de este estudio en detalle, se intentar realizar una comparacin y anlisis basados en las ms importantes caractersticas para las tcnicas biomtricas, fiabilidad, facilidad, usurpacin, aceptacin y estabilidad, etc. ABSTRACT The following Master's Thesis is divided into three parts, always, about biometric identification. This science fail that certain biological or behavioural characteristics unique and unchangeable, so it can be analysed and measured to create a biometric fingerprint. These features are hard to miss, or forget to transfer and are enduring in time. In the first part a vision of the historical importance of this science are offered, from the earliest human remains in the area of Mesopotamia, to the great innovators and pioneers of biometric identification, such as Bertillon, Galton, Vucetich, etc. . sponsored a largely forensic or detective purpose, until the great revolution in the late nineteenth century, in which techniques that seemed science fiction became reality. The following section will analyse the 6 main techniques currently in use, making a deeper look at the natural, physiological and physical principles on which future trends are based on the industry to work for the development of techniques will be discussed more safer, less invasive and more transparent to end users. Such as has happened throughout history sounded amazing, but once again the human race get materialize and introduce them in their day to day. Finally and after the study in detail, and try to make a comparison based on the most important features for biometric technologies, reliability, ease, alienation, acceptance and stability analysis etc..
Resumo:
En entornos hostiles tales como aquellas instalaciones cientficas donde la radiacin ionizante es el principal peligro, el hecho de reducir las intervenciones humanas mediante el incremento de las operaciones robotizadas est siendo cada vez ms de especial inters. CERN, la Organizacin Europea para la Investigacin Nuclear, tiene alrededor de unos 50 km de superficie subterrnea donde robots mviles controlador de forma remota podran ayudar en su funcionamiento, por ejemplo, a la hora de llevar a cabo inspecciones remotas sobre radiacin en los diferentes reas destinados al efecto. No solo es preciso considerar que los robots deben ser capaces de recorrer largas distancias y operar durante largos periodos de tiempo, sino que deben saber desenvolverse en los correspondientes tneles subterrneos, tener en cuenta la presencia de campos electromagnticos, radiacin ionizante, etc. y finalmente, el hecho de que los robots no deben interrumpir el funcionamiento de los aceleradores. El hecho de disponer de un sistema de comunicaciones inalmbrico fiable y robusto es esencial para la correcta ejecucin de las misiones que los robots deben afrontar y por supuesto, para evitar tales situaciones en las que es necesario la recuperacin manual de los robots al agotarse su energa o al perder el enlace de comunicaciones. El objetivo de esta Tesis es proveer de las directrices y los medios necesarios para reducir el riesgo de fallo en la misin y maximizar las capacidades de los robots mviles inalmbricos los cuales disponen de almacenamiento finito de energa al trabajar en entornos peligrosos donde no se dispone de lnea de vista directa. Para ello se proponen y muestran diferentes estrategias y mtodos de comunicacin inalmbrica. Teniendo esto en cuenta, se presentan a continuacin los objetivos de investigacin a seguir a lo largo de la Tesis: predecir la cobertura de comunicaciones antes y durante las misiones robotizadas; optimizar la capacidad de red inalmbrica de los robots mviles con respecto a su posicin; y mejorar el rango operacional de esta clase de robots. Por su parte, las contribuciones a la Tesis se citan ms abajo. El primer conjunto de contribuciones son mtodos novedosos para predecir el consumo de energa y la autonoma en la comunicacin antes y despus de disponer de los robots en el entorno seleccionado. Esto es importante para proporcionar conciencia de la situacin del robot y evitar fallos en la misin. El consumo de energa se predice usando una estrategia propuesta la cual usa modelos de consumo provenientes de diferentes componentes en un robot. La prediccin para la cobertura de comunicaciones se desarrolla usando un nuevo filtro de RSS (Radio Signal Strength) y tcnicas de estimacin con la ayuda de Filtros de Kalman. El segundo conjunto de contribuciones son mtodos para optimizar el rango de comunicaciones usando novedosas tcnicas basadas en muestreo espacial que son robustas frente a ruidos de campos de deteccin y radio y que proporcionan redundancia. Se emplean mtodos de diferencia central finitos para determinar los gradientes 2D RSS y se usa la movilidad del robot para optimizar el rango de comunicaciones y la capacidad de red. Este mtodo tambin se valida con un caso de estudio centrado en la teleoperacin hptica de robots mviles inalmbricos. La tercera contribucin es un algoritmo robusto y estocstico descentralizado para la optimizacin de la posicin al considerar mltiples robots autnomos usados principalmente para extender el rango de comunicaciones desde la estacin de control al robot que est desarrollando la tarea. Todos los mtodos y algoritmos propuestos se verifican y validan usando simulaciones y experimentos de campo con variedad de robots mviles disponibles en CERN. En resumen, esta Tesis ofrece mtodos novedosos y demuestra su uso para: predecir RSS; optimizar la posicin del robot; extender el rango de las comunicaciones inalmbricas; y mejorar las capacidades de red de los robots mviles inalmbricos para su uso en aplicaciones dentro de entornos peligrosos, que como ya se mencion anteriormente, se destacan las instalaciones cientficas con emisin de radiacin ionizante. En otros trminos, se ha desarrollado un conjunto de herramientas para mejorar, facilitar y hacer ms seguras las misiones de los robots en entornos hostiles. Esta Tesis demuestra tanto en teora como en prctica que los robots mviles pueden mejorar la calidad de las comunicaciones inalmbricas mediante la profundizacin en el estudio de su movilidad para optimizar dinmicamente sus posiciones y mantener conectividad incluso cuando no existe lnea de vista. Los mtodos desarrollados en la Tesis son especialmente adecuados para su fcil integracin en robots mviles y pueden ser aplicados directamente en la capa de aplicacin de la red inalmbrica. ABSTRACT In hostile environments such as in scientific facilities where ionising radiation is a dominant hazard, reducing human interventions by increasing robotic operations are desirable. CERN, the European Organization for Nuclear Research, has around 50 km of underground scientific facilities, where wireless mobile robots could help in the operation of the accelerator complex, e.g. in conducting remote inspections and radiation surveys in different areas. The main challenges to be considered here are not only that the robots should be able to go over long distances and operate for relatively long periods, but also the underground tunnel environment, the possible presence of electromagnetic fields, radiation effects, and the fact that the robots shall in no way interrupt the operation of the accelerators. Having a reliable and robust wireless communication system is essential for successful execution of such robotic missions and to avoid situations of manual recovery of the robots in the event that the robot runs out of energy or when the robot loses its communication link. The goal of this thesis is to provide means to reduce risk of mission failure and maximise mission capabilities of wireless mobile robots with finite energy storage capacity working in a radiation environment with non-line-of-sight (NLOS) communications by employing enhanced wireless communication methods. Towards this goal, the following research objectives are addressed in this thesis: predict the communication range before and during robotic missions; optimise and enhance wireless communication qualities of mobile robots by using robot mobility and employing multi-robot network. This thesis provides introductory information on the infrastructures where mobile robots will need to operate, the tasks to be carried out by mobile robots and the problems encountered in these environments. The reporting of research work carried out to improve wireless communication comprises an introduction to the relevant radio signal propagation theory and technology followed by explanation of the research in the following stages: An analysis of the wireless communication requirements for mobile robot for different tasks in a selection of CERN facilities; predictions of energy and communication autonomies (in terms of distance and time) to reduce risk of energy and communication related failures during missions; autonomous navigation of a mobile robot to find zone(s) of maximum radio signal strength to improve communication coverage area; and autonomous navigation of one or more mobile robots acting as mobile wireless relay (repeater) points in order to provide a tethered wireless connection to a teleoperated mobile robot carrying out inspection or radiation monitoring activities in a challenging radio environment. The specific contributions of this thesis are outlined below. The first sets of contributions are novel methods for predicting the energy autonomy and communication range(s) before and after deployment of the mobile robots in the intended environments. This is important in order to provide situational awareness and avoid mission failures. The energy consumption is predicted by using power consumption models of different components in a mobile robot. This energy prediction model will pave the way for choosing energy-efficient wireless communication strategies. The communication range prediction is performed using radio signal propagation models and applies radio signal strength (RSS) filtering and estimation techniques with the help of Kalman filters and Gaussian process models. The second set of contributions are methods to optimise the wireless communication qualities by using novel spatial sampling based techniques that are robust to sensing and radio field noises and provide redundancy features. Central finite difference (CFD) methods are employed to determine the 2-D RSS gradients and use robot mobility to optimise the communication quality and the network throughput. This method is also validated with a case study application involving superior haptic teleoperation of wireless mobile robots where an operator from a remote location can smoothly navigate a mobile robot in an environment with low-wireless signals. The third contribution is a robust stochastic position optimisation algorithm for multiple autonomous relay robots which are used for wireless tethering of radio signals and thereby to enhance the wireless communication qualities. All the proposed methods and algorithms are verified and validated using simulations and field experiments with a variety of mobile robots available at CERN. In summary, this thesis offers novel methods and demonstrates their use to predict energy autonomy and wireless communication range, optimise robots position to improve communication quality and enhance communication range and wireless network qualities of mobile robots for use in applications in hostile environmental characteristics such as scientific facilities emitting ionising radiations. In simpler terms, a set of tools are developed in this thesis for improving, easing and making safer robotic missions in hostile environments. This thesis validates both in theory and experiments that mobile robots can improve wireless communication quality by exploiting robots mobility to dynamically optimise their positions and maintain connectivity even when the (radio signal) environment possess non-line-of-sight characteristics. The methods developed in this thesis are well-suited for easier integration in mobile robots and can be applied directly at the application layer of the wireless network. The results of the proposed methods have outperformed other comparable state-of-the-art methods.
Resumo:
Los patgenos han desarrollado estrategias para sobrevivir en su entorno, infectar a sus huspedes, multiplicarse dentro de estos y posteriormente transmitirse a otros huspedes. Todos estos componentes hacen parte de la eficacia biolgica de los patgenos, y les permiten ser los causantes de enfermedades infecciosas tanto en hombres y animales, como en plantas. El proceso de infeccin produce efectos negativos en la eficacia biolgica del husped y la gravedad de los efectos, depender de la virulencia del patgeno. Por su parte, el husped ha desarrollado mecanismos de respuesta en contra del patgeno, tales como la resistencia, por la que reduce la multiplicacin del patgeno, o la tolerancia, por la que disminuye el efecto negativo de la infeccin. Estas respuestas del husped a la infeccin producen efectos negativos en la eficacia biolgica del patgeno, actuando como una presin selectiva sobre su poblacin. Si la presin selectiva sobre el patgeno vara segn el husped, se predice que un mismo patgeno no podr aumentar su eficacia biolgica en distintos huspedes y estar ms adaptado a un husped y menos a otro, disminuyendo su gama de huspedes. Esto supone que la adaptacin de un patgeno a distintos huspedes estar a menudo dificultada por compromisos (trade-off) en diferentes componentes de la eficacia biolgica del patgeno. Hasta el momento, la evidencia de compromisos de la adaptacin del patgeno a distintos huspedes no es muy abundante, en lo que se respecta a los virus de plantas. En las ltimas dcadas, se ha descrito un aumento en la incidencia de virus nuevos o previamente descritos que producen enfermedades infecciosas con mayor gravedad y/o diferente patogenicidad, como la infeccin de huspedes previamente resistentes. Esto se conoce como la emergencia de enfermedades infecciosas y est causada por patgenos emergentes, que proceden de un husped reservorio donde se encuentran adaptados. Los huspedes que actan como reservorios pueden ser plantas silvestres, que a menudo presentan pocos sntomas o muy leves a pesar de estar infectados con diferentes virus, y asimismo se encuentran en ecosistemas con ninguna o poca intervencin humana. El estudio de los factores ecolgicos y biolgicos que actan en el proceso de la emergencia de enfermedades infecciosas, ayudar a entender sus causas para crear estrategias de prevencin y control. Los virus son los principales patgenos causales de la emergencia de enfermedades infecciosas en humanos, animales y plantas y un buen modelo para entender los procesos de la emergencia. Asimismo, las plantas a diferencia de los animales, son huspedes fciles de manipular y los virus que las afectan, ms seguros para el trabajo en laboratorio que los virus de humanos y animales, otros modelos tambin usados en la investigacin. Por lo tanto, la interaccin virus planta es un buen modelo experimental para el estudio de la emergencia de enfermedades infecciosas. El estudio de la emergencia de virus en plantas tiene tambin un inters particular, debido a que los virus pueden ocasionar prdidas econmicas en los cultivos agrcolas y poner en riesgo la durabilidad de la resistencia de plantas mejoradas, lo que supone un riesgo en la seguridad alimentaria con impactos importantes en la sociedad, comparables con las enfermedades infecciosas de humanos y animales domsticos. Para que un virus se convierta en un patgeno emergente debe primero saltar desde su husped reservorio a un nuevo husped, segundo adaptarse al nuevo husped hasta que la infeccin dentro de la poblacin de ste se vuelva independiente del reservorio y finalmente debe cambiar su epidemiologa. En este estudio, se escogi la emergencia del virus del mosaico del pepino dulce (PepMV) en el tomate, como modelo experimental para estudiar la emergencia de un virus en una nueva especie de husped, as como las infecciones de distintos genotipos del virus del moteado atenuado del pimiento (PMMoV) en pimiento, para estudiar la emergencia de un virus que aumenta su patogenicidad en un husped previamente resistente. El estudio de ambos patosistemas nos permiti ampliar el conocimiento sobre los factores ecolgicos y evolutivos en las dos primeras fases de la emergencia de enfermedades virales en plantas. El PepMV es un patgeno emergente en cultivos de tomate (Solanum lycopersicum) a nivel mundial, que se describi primero en 1980 infectando pepino dulce (Solanum muricatum L.) en Per, y casi una dcada despus causando una epidemia en cultivos de tomate en Holanda. La introduccin a Europa posiblemente fue a travs de semillas infectadas de tomate procedentes de Per, y desde entonces se han descrito nuevos aislados que se agrupan en cuatro cepas (EU, LP, CH2, US1) que infectan a tomate. Sin embargo, el proceso de su emergencia desde pepino dulce hasta tomate es un interrogante de gran inters, porque es uno de los virus emergentes ms recientes y de gran importancia econmica. Para la emergencia de PepMV en tomate, se recolectaron muestras de tomate silvestre procedentes del sur de Per, se analiz la presencia y diversidad de aislados de PepMV y se caracterizaron tanto biolgicamente (gama de huspedes), como genticamente (secuencias genomicas). Se han descrito en diferentes regiones del mundo aislados de PMMoV que han adquirido la capacidad de infectar variedades previamente resistentes de pimiento (Capsicum spp), es decir, un tpico caso de emergencia de virus que implica la ampliacin de su gama de huspedes y un aumento de patogenicidad. Esto tiene gran inters, ya que compromete el uso de variedades resistentes obtenidas por mejora gentica, que es la forma de control de virus ms eficaz que existe. Para estudiar la emergencia de genotipos altamente patognicos de PMMoV, se analizaron clones biolgicos de PMMoV procedentes de aislados de campo cuya patogenicidad era conocida (P1,2) y por mutagnesis se les aument la patogenicidad (P1,2,3 y P1,2,3,4), introduciendo las mutaciones descritas como responsables de estos fenotipos. Se analiz si el aumento de la patogenicidad conlleva un compromiso en la eficacia biolgica de los genotipos de PMMoV. Para ello se evaluaron diferentes componentes de la eficacia biolgica del virus en diferentes huspedes con distintos alelos de resistencia. Los resultados de esta tesis demuestran: i). El potencial de las plantas silvestres como reservorios de virus emergentes, en este caso tomates silvestres del sur de Per, as como la existencia en estas plantas de aislados de PepMV de una nueva cepa no descrita que llamamos PES. ii) El aumento de la gama de huspedes no es una condicin estricta para la emergencia de los virus de plantas. iii) La adaptacin es el mecanismo ms probable en la emergencia de PepMV en tomate cultivado. iv) El aumento de la patogenicidad tiene un efecto pleiotrpico en distintos componentes de la eficacia biolgica, as mismo el signo y magnitud de este efecto depender del genotipo del virus, del husped y de la interaccin de estos factores. ABSTRACT host Pathogens have evolved strategies to survive in their environment, infecting their hosts, multiplying inside them and being transmitted to other hosts. All of these components form part of the pathogen fitness, and allow them to be the cause of infectious diseases in humans, animals, and plants. The infection process produces negative effects on the host fitness and the effects severity will depend on the pathogen virulence. On the other hand, hosts have developed response mechanisms against pathogens such as resistance, which reduces the growth of pathogens, or tolerance, which decreases the negative effects of infection. T he se responses of s to infection cause negative effects on the pathogen fitness, acting as a selective pressure on its population. If the selective pressures on pathogens va ry according to the host s , probably one pathogen cannot increase its fitness in different hosts and will be more adapted to one host and less to another, decreasing its host range. This means that the adaptation of one pathogen to different hosts , will be often limited by different trade - off components of biological effectiveness of pathogen. Nowadays , trade - off evidence of pathogen adaptation to different hosts is not extensive, in relation with plant viruses. In last decades, an increase in the incidence of new or previously detected viruses has been described, causing infectious diseases with increased severity and/or different pathogenicity, such as the hosts infection previously resistants. This is known as the emergence of infectious diseases and is caused by emerging pathogens that come from a reservoir host where they are adapted. The hosts which act as reservoirs can be wild plants, that often have few symptoms or very mild , despite of being infected with different viruses, and being found in ecosystems with little or any human intervention. The study of ecological and biological factors , acting in the process of the infectious diseases emergence will help to understand its causes to create strategies for its prevention and control. Viruses are the main causative pathogens of the infectious diseases emergence in humans, animals and plants, and a good model to understand the emergency processes. Likewise, plants in contrast to animals are easy host to handle and viruses that affect them, safer for laboratory work than viruses of humans and animals, another models used in research. Therefore, the interaction plant-virus is a good experimental model for the study of the infectious diseases emergence. The study of virus emergence in plants also has a particular interest, because the viruses can cause economic losses in agricultural crops and threaten the resistance durability of improved plants, it suppose a risk for food security with significant impacts on society, comparable with infectious diseases of humans and domestic animals. To become an emerging pathogen, a virus must jump first from its reservoir host to a new host, then adapt to a new host until the infection within the population becomes independent from the reservoir, and finally must change its epidemiology. In this study, the emergence of pepino mosaic virus (PepMV) in tomato, was selected as experimental model to study the emergence of a virus in a new host specie, as well as the infections of different genotypes of pepper mild mottle virus (PMMoV) in pepper, to study the emergence of a virus that increases its pathogenicity in a previously resistant host. The study of both Pathosystems increased our knowledge about the ecological and evolutionary factors in the two first phases of the emergence of viral diseases in plants. The PepMV is an emerging pathogen in tomato (Solanum lycopersicum L.) in the world, which was first described in 1980 by infecting pepino (Solanum muricatum L.) in Peru, and almost after a decade caused an epidemic in tomato crops in Netherlands. The introduction to Europe was possibly through infected tomato seeds from Peru, and from then have been described new isolates that are grouped in four strains (EU, LP, CH2, US1) that infect tomato. However, the process of its emergence from pepino up tomato is a very interesting question, because it is one of the newest emerging viruses and economically important. For the PepMV emergence in tomato, wild tomato samples from southern Peru were collected, and the presence and diversity of PepMV isolates were analyzed and characterized at biological (host range) and genetics (genomic sequences) levels. Isolates from PMMoV have been described in different world regions which have acquired the ability to infect pepper varieties that were previously resistants (Capsicum spp), it means, a typical case of virus emergence which involves the host range extension and an increased pathogenicity. This is of great interest due to involve the use of resistant varieties obtained by breeding, which is the most effective way to control virus. To study the emergence of highly pathogenic genotypes of PMMoV, biological clones from field isolates whose pathogenicity was known were analyzed (P1,2) and by mutagenesis we increased its pathogenicity (P1,2,3 and P1,2, 3,4), introducing the mutations described as responsible for these phenotypes. We analyzed whether the increased pathogenicity involves a trade-off in fitness of PMMoV genotypes. For this aim, different components of virus fitness in different hosts with several resistance alleles were evaluated. The results of this thesis show: i). The potential of wild plants as reservoirs of emerging viruses, in this case wild tomatoes in southern Peru, and the existence in these plants of PepMV isolates of a new undescribed strain that we call PES. ii) The host range expansion is not a strict condition for the plant virus emergence. iii) The adaptation is the most likely mechanism in the PepMV emergence in cultivated tomato. iv) The increased pathogenicity has a pleiotropic effect on several fitness components, besides the sign and magnitude of this effect depends on the virus genotype, the host and the interaction of both.
Resumo:
El riesgo asociado a la rotura de un depsito de agua en entorno urbano (como la ocurrida, por ejemplo, en la Ciudad Autnoma de Melilla en Noviembre de 1997) y los potenciales daos que puede causar, pone en duda la seguridad de este tipo de infraestructuras que, por necesidades del servicio de abastecimiento de agua, se construyen habitualmente en puntos altos y cercanos a los ncleos de poblacin a los que sirven. Sin embargo, la baja probabilidad de que se produzca una rotura suele rebajar los niveles de alerta asociados a los depsitos, hacindose hincapi en la mejora de los mtodos constructivos sin elaborar metodologas que, como en el caso de las presas y las balsas de riego, establezcan la necesidad de clasificar el riesgo potencial de estas infraestructuras en funcin de su emplazamiento y de estudiar la posible construccin de medidas mitigadoras de una posible rotura. Por otro lado, para establecer los daos que pueden derivarse de una rotura de este tipo, se hace imprescindible la modelizacin bidimensional de la ola de rotura por cuanto la malla urbana a la que afectaran no es susceptible de simulaciones unidimensionales, dado que no hay un cauce que ofrezca un camino preferente al agua. Este tipo de simulacin requiere de una inversin econmica que no siempre est disponible en la construccin de depsitos de pequeo y mediano tamao. Esta tesis doctoral tiene como objetivo el diseo de una metodologa simplificada que, por medio de graficas y atendiendo a las variables principales del fenmeno, pueda estimar un valor para el riesgo asociado a una posible rotura y sirva como gua para establecer si un deposito (existente o de nueva implantacin) requiere de un modelo de detalle para estimar el riesgo y si es conveniente implantar alguna medida mitigadora de la energa producida en una rotura de este tipo. Con carcter previo se ha establecido que las variables que intervienen en la definicin de riesgo asociado a la rotura, son el calado y la velocidad mxima en cada punto sensible de sufrir daos (daos asociados al vuelco y arrastre de personas principalmente), por lo que se ha procedido a estudiar las ecuaciones que rigen el problema de la rotura del depsito y de la transmisin de la onda de rotura por la malla urbana adyacente al mismo, as como los posibles mtodos de resolucin de las mismas y el desarrollo informtico necesario para una primera aproximacin a los resultados. Para poder analizar las condiciones de contorno que influyen en los valores resultantes de velocidad y calado, se ha diseado una batera de escenarios simplificados que, tras una modelizacin en detalle y un anlisis adimensional, han dado como resultado que las variables que influyen en los valores de calado y velocidad mximos en cada punto son: la altura de la lamina de agua del depsito, la pendiente del terreno, la rugosidad, la forma del terreno (en trminos de concavidad) y la distancia del punto de estudio al deposito. Una vez definidas las variables que influyen en los resultados, se ha llevado a cabo una segunda batera de simulaciones de escenarios simplificados que ha servido para la discusin y desarrollo de las curvas que se presentan como producto principal de la metodologa simplificada. Con esta metodologa, que solamente necesita de unos clculos simples para su empleo, se obtiene un primer valor de calado y velocidad introduciendo la altura de la lmina de agua mxima de servicio del depsito cuyo riesgo se quiere evaluar. Posteriormente, y utilizando el baco propuesto, se obtienen coeficientes correctores de los valores obtenidos para la rugosidad y pendiente media del terreno que se esta evaluando, as como para el grado de concavidad del mismo (a travs de la pendiente transversal). Con los valores obtenidos con las curvas anteriores se obtienen los valores de calado y velocidad en el punto de estudio y, aplicando la formulacin propuesta, se obtiene una estimacin del riesgo asociado a la rotura de la infraestructura. Como corolario a la metodologa mencionada, se propone una segunda serie de grficos para evaluar, tambin de forma simplificada, la reduccin del riesgo que se obtendra con la construccin de alguna medida mitigadora como puede ser un dique o murete perimetral al depsito. Este mtodo de evaluacin de posible medidas mitigadoras, aporta una gua para analizar la posibilidad de disminuir el riesgo con la construccin de estos elementos, o la necesidad de buscar otro emplazamiento que, si bien pueda ser no tan favorable desde el punto de vista de la explotacin del depsito, presente un menor riesgo asociado a su rotura. Como complemento a la metodologa simplificada propuesta, y adems de llevar a cabo la calibracin de la misma con los datos obtenidos tras la rotura del depsito de agua de Melilla, se ha realizado una serie de ejemplos de utilizacin de la metodologa para, adems de servir de gua de uso de la misma, poder analizar la diferencia entre los resultados que se obtendran con una simulacin bidimensional detallada de cada uno de los casos y el mtodo simplificado aplicado a los mismos. The potential risk of a catastrophic collapse of a water supply reservoir in an urban area (such as the one occurred in Melilla in November 1997) and the damages that can cause, make question the security in this kind of infrastructures, which, by operational needs, are frequently built in high elevations and close to the urban areas they serve to. Since the likelihood of breakage is quite low, the alert levels associated to those infrastructures have also been downgraded focussing on the improvement of the constructive methods without developing methodologies (like the ones used in the case of dams or irrigation ponds) where there is a need of classifying the potential risk of those tanks and also of installing mitigating measures. Furthermore, to establish the damages related to a breakage of this kind, a twodimensional modelling of the breakage wave becomes imperative given that the urban layout does not provide a preferential way to the water. This kind of simulation requires financial investment that is not always available in the construction of small and medium sized water tanks. The purpose of this doctoral thesis is to design a simplified methodology, by means of charts and attending to the main variables of the phenomenon, that could estimate a value to the risk associated to a possible breakage. It can also be used as a guidance to establish if a reservoir (existing or a new one) requires a detailed model to estimate the risk of a breakage and the benefits of installing measures to mitigate the breakage wave effects. Previously, it has been established that the variables involved in the risk associated to a breakage are the draft and the maximum speed in every point susceptible to damages (mainly damages related to people). Bellow, the equations ruling the problem of the reservoir breakage have been studied as well as the transmission of the breakage wave through the urban network of the city and the possible methods to solve the equations and the computer development needed to a first approach to the results. In order to be able to analyse the boundary conditions affecting the values resulting (speed and draft), a set of scenarios have been designed. After a detailed modelling and a dimensionless analysis it has been proved that the variables that influence the operational draughts and the maximum speed in every point are the water level in the tank, the slope, the roughness and form (in terms of concavity) of the terrain and the distance between the tank and the control point. Having defined the involving variables, a second set of simulations of the simplified scenarios has been carried out and has helped to discuss and develop the curves that are here presented as the final product of the simplified methodology. This methodology only needs some simple calculations and gives a first value of draft and speed by introducing the maximum water level of the tank being evaluated. Subsequently, using the suggested charts, the method gives correction coefficients of the measured values for roughness and average slope of the assessed terrain as well as the degree of concavity (through transverse gradient).With the values from the previous curves (operational draughts and speed at the point of survey) and applying the proposed formulation, an estimation of the risk associated to the breakage of the infrastructure is finally obtained. As a corollary of the mentioned methodology, another set of diagrams is proposed in order to evaluate, in a simplified manner also, the risk reduction that could be gained with the construction of some mitigating measures such as dikes or retaining walls around the reservoir. This evaluating method provides a guide to analyse the possibility to reduce the risk, constructing those elements or even looking for a different site that could be worse in terms of exploitation of the tank but much safer. As a complement to the simplified methodology here proposed, and apart from completing its calibration with the obtained data after the reservoir breakage in Melilla, a number of examples of the use of the methodology have been made to be used as a user guide of the methodology itself, as well as giving the possibility of analysing the different results that can be obtained from a thorough two-dimensional simulation or from the simplified method applied to the examples.
Resumo:
Habitualmente en los ensayos de barcos amarrados se reproduce la accin del oleaje. Se ha diseado un sistema para la reproduccin del efecto del viento en estos ensayos, utilizando motores, poleas, hilos de conexin, muelles, galgas y controladoras, de forma que la fuerza ejercida por el viento, previamente calculada considerando las caractersticas del barco y del viento, se transmite al barco mediante los elementos que componen el sistema. Este sistema consiste en un circuito cerrado de transmisin de fuerza con un motor que simultneamente acta sobre dos muelles deformndolos en sentidos opuestos, los cuales transmiten las fuerzas en los costados del buque, siendo la diferencia del alargamiento de los muelles la fuerza resultante sobre el barco. El sistema se aplic a un buque crucero, obteniendo unos resultados que muestran la importancia de tener en cuenta el viento racheado como un agente adicional al oleaje que provoca movimientos y esfuerzos en las amarras y defensas elevados, dependiendo de su intensidad y direccin. Se ensayaron tres condiciones: modelo alimentado nicamente con olas, solo con viento y con ambos. En cada ensayo realizado se registraron los movimientos del buque, las fuerzas en las amarras y las reacciones en las defensas. La aportacin de la Tesis es un sistema mecnico para excitar el modelo del buque amarrado con viento racheado superpuesto a la accin del oleaje. Evidentemente los resultados que se obtengan se ajustarn ms a la situacin real que reproduciendo slo el oleaje. ABSTRACT Traditionally, moored ship tests with small-scale models only take into account the disturbance effect of waves. In this thesis, the design and testing of a system also implementing the effect of wind in moored ships is analyzed. The system is based on rotatory actuators acting on linear springs. This solution has a swift enough response to reproduce the fluctuating component of the wind. Three scenarios have been tested: waves, wind and combination of both. In order to assess the results, different sensors are connected to a computer for data acquisition, allowing the recording and subsequent analysis of the measured variables (forces in ropes, reactions in fenders and ship motions). The results obtained from the experiments show a great impact when wind effect is considered. A superposition effect is observed when waves and wind act together on the ship, emphasizing therefore the importance of taking the wind into account in berthed vessel tests, achieving safer and more realistic results.