35 resultados para Situations of validation
em Universidad Politécnica de Madrid
Resumo:
A study on the manoeuvrability of a riverine support patrol vessel is made to derive a mathematical model and simulate maneuvers with this ship. The vessel is mainly characterized by both its wide-beam and the unconventional propulsion system, that is, a pump-jet type azimuthal propulsion. By processing experimental data and the ship characteristics with diverse formulae to find the proper hydrodynamic coefficients and propulsion forces, a system of three differential equations is completed and tuned to carry out simulations of the turning test. The simulation is able to accept variable speed, jet angle and water depth as input parameters and its output consists of time series of the state variables and a plot of the simulated path and heading of the ship during the maneuver. Thanks to the data of full-scale trials previously performed with the studied vessel, a process of validation was made, which shows a good fit between simulated and full-scale experimental results, especially on the turning diameter
Resumo:
Los incendios forestales son la principal causa de mortalidad de árboles en la Europa mediterránea y constituyen la amenaza más seria para los ecosistemas forestales españoles. En la Comunidad Valenciana, diariamente se despliega cerca de un centenar de vehículos de vigilancia, cuya distribución se apoya, fundamentalmente, en un índice de riesgo de incendios calculado en función de las condiciones meteorológicas. La tesis se centra en el diseño y validación de un nuevo índice de riesgo integrado de incendios, especialmente adaptado a la región mediterránea y que facilite el proceso de toma de decisiones en la distribución diaria de los medios de vigilancia contra incendios forestales. El índice adopta el enfoque de riesgo integrado introducido en la última década y que incluye dos componentes de riesgo: el peligro de ignición y la vulnerabilidad. El primero representa la probabilidad de que se inicie un fuego y el peligro potencial para que se propague, mientras que la vulnerabilidad tiene en cuenta las características del territorio y los efectos potenciales del fuego sobre el mismo. Para el cálculo del peligro potencial se han identificado indicadores relativos a los agentes naturales y humanos causantes de incendios, la ocurrencia histórica y el estado de los combustibles, extremo muy relacionado con la meteorología y las especies. En cuanto a la vulnerabilidad se han empleado indicadores representativos de los efectos potenciales del incendio (comportamiento del fuego, infraestructuras de defensa), como de las características del terreno (valor, capacidad de regeneración…). Todos estos indicadores constituyen una estructura jerárquica en la que, siguiendo las recomendaciones de la Comisión europea para índices de riesgo de incendios, se han incluido indicadores representativos del riesgo a corto plazo y a largo plazo. El cálculo del valor final del índice se ha llevado a cabo mediante la progresiva agregación de los componentes que forman cada uno de los niveles de la estructura jerárquica del índice y su integración final. Puesto que las técnicas de decisión multicriterio están especialmente orientadas a tratar con problemas basados en estructuras jerárquicas, se ha aplicado el método TOPSIS para obtener la integración final del modelo. Se ha introducido en el modelo la opinión de los expertos, mediante la ponderación de cada uno de los componentes del índice. Se ha utilizado el método AHP, para obtener las ponderaciones de cada experto y su integración en un único peso por cada indicador. Para la validación del índice se han empleado los modelos de Ecuaciones de Estimación Generalizadas, que tienen en cuenta posibles respuestas correlacionadas. Para llevarla a cabo se emplearon los datos de oficiales de incendios ocurridos durante el período 1994 al 2003, referenciados a una cuadrícula de 10x10 km empleando la ocurrencia de incendios y su superficie, como variables dependientes. Los resultados de la validación muestran un buen funcionamiento del subíndice de peligro de ocurrencia con un alto grado de correlación entre el subíndice y la ocurrencia, un buen ajuste del modelo logístico y un buen poder discriminante. Por su parte, el subíndice de vulnerabilidad no ha presentado una correlación significativa entre sus valores y la superficie de los incendios, lo que no descarta su validez, ya que algunos de sus componentes tienen un carácter subjetivo, independiente de la superficie incendiada. En general el índice presenta un buen funcionamiento para la distribución de los medios de vigilancia en función del peligro de inicio. No obstante, se identifican y discuten nuevas líneas de investigación que podrían conducir a una mejora del ajuste global del índice. En concreto se plantea la necesidad de estudiar más profundamente la aparente correlación que existe en la provincia de Valencia entre la superficie forestal que ocupa cada cuadrícula de 10 km del territorio y su riesgo de incendios y que parece que a menor superficie forestal, mayor riesgo de incendio. Otros aspectos a investigar son la sensibilidad de los pesos de cada componente o la introducción de factores relativos a los medios potenciales de extinción en el subíndice de vulnerabilidad. Summary Forest fires are the main cause of tree mortality in Mediterranean Europe and the most serious threat to the Spanisf forest. In the Spanish autonomous region of Valencia, forest administration deploys a mobile fleet of 100 surveillance vehicles in forest land whose allocation is based on meteorological index of wildlandfire risk. This thesis is focused on the design and validation of a new Integrated Wildland Fire Risk Index proposed to efficient allocation of vehicles and specially adapted to the Mediterranean conditions. Following the approaches of integrated risk developed last decade, the index includes two risk components: Wildland Fire Danger and Vulnerability. The former represents the probability a fire ignites and the potential hazard of fire propagation or spread danger, while vulnerability accounts for characteristics of the land and potential effects of fire. To calculate the Wildland Fire Danger, indicators of ignition and spread danger have been identified, including human and natural occurrence agents, fuel conditions, historical occurrence and spread rate. Regarding vulnerability se han empleado indicadores representativos de los efectos potenciales del incendio (comportamiento del fuego, infraestructurasd de defensa), como de las características del terreno (valor, capacidad de regeneración…). These indicators make up the hierarchical structure for the index, which, following the criteria of the European Commission both short and long-term indicators have been included. Integration consists of the progressive aggregation of the components that make up every level in risk the index and, after that, the integration of these levels to obtain a unique value for the index. As Munticriteria methods are oriented to deal with hierarchically structured problems and with situations in which conflicting goals prevail, TOPSIS method is used in the integration of components. Multicriteria methods were also used to incorporate expert opinion in weighting of indicators and to carry out the aggregation process into the final index. The Analytic Hierarchy Process method was used to aggregate experts' opinions on each component into a single value. Generalized Estimation Equations, which account for possible correlated responses, were used to validate the index. Historical records of daily occurrence for the period from 1994 to 2003, referred to a 10x10-km-grid cell, as well as the extent of the fires were the dependant variables. The results of validation showed good Wildland Fire Danger component performance, with high correlation degree between Danger and occurrence, a good fit of the logistic model used and a good discrimination power. The vulnerability component has not showed a significant correlation between their values and surface fires, which does not mean the index is not valid, because of the subjective character of some of its components, independent of the surface of the fires. Overall, the index could be used to optimize the preventing resources allocation. Nevertheless, new researching lines are identified and discussed to improve the overall performance of the index. More specifically the need of study the inverse relationship between the value of the wildfire Fire Danger component and the forested surface of each 10 - km cell is set out. Other points to be researched are the sensitivity of the index component´s weight and the possibility of taking into account indicators related to fire fighting resources to make up the vulnerability component.
Resumo:
Natural regeneration is an ecological key-process that makes plant persistence possible and, consequently, it constitutes an essential element of sustainable forest management. In this respect, natural regeneration in even-aged stands of Pinus pinea L. located in the Spanish Northern Plateau has not always been successfully achieved despite over a century of pine nut-based management. As a result, natural regeneration has recently become a major concern for forest managers when we are living a moment of rationalization of investment in silviculture. The present dissertation is addressed to provide answers to forest managers on this topic through the development of an integral regeneration multistage model for P. pinea stands in the region. From this model, recommendations for natural regeneration-based silviculture can be derived under present and future climate scenarios. Also, the model structure makes it possible to detect the likely bottlenecks affecting the process. The integral model consists of five submodels corresponding to each of the subprocesses linking the stages involved in natural regeneration (seed production, seed dispersal, seed germination, seed predation and seedling survival). The outputs of the submodels represent the transitional probabilities between these stages as a function of climatic and stand variables, which in turn are representative of the ecological factors driving regeneration. At subprocess level, the findings of this dissertation should be interpreted as follows. The scheduling of the shelterwood system currently conducted over low density stands leads to situations of dispersal limitation since the initial stages of the regeneration period. Concerning predation, predator activity appears to be only limited by the occurrence of severe summer droughts and masting events, the summer resulting in a favourable period for seed survival. Out of this time interval, predators were found to almost totally deplete seed crops. Given that P. pinea dissemination occurs in summer (i.e. the safe period against predation), the likelihood of a seed to not be destroyed is conditional to germination occurrence prior to the intensification of predator activity. However, the optimal conditions for germination seldom take place, restraining emergence to few days during the fall. Thus, the window to reach the seedling stage is narrow. In addition, the seedling survival submodel predicts extremely high seedling mortality rates and therefore only some individuals from large cohorts will be able to persist. These facts, along with the strong climate-mediated masting habit exhibited by P. pinea, reveal that viii the overall probability of establishment is low. Given this background, current management –low final stand densities resulting from intense thinning and strict felling schedules– conditions the occurrence of enough favourable events to achieve natural regeneration during the current rotation time. Stochastic simulation and optimisation computed through the integral model confirm this circumstance, suggesting that more flexible and progressive regeneration fellings should be conducted. From an ecological standpoint, these results inform a reproductive strategy leading to uneven-aged stand structures, in full accordance with the medium shade-tolerant behaviour of the species. As a final remark, stochastic simulations performed under a climate-change scenario show that regeneration in the species will not be strongly hampered in the future. This resilient behaviour highlights the fundamental ecological role played by P. pinea in demanding areas where other tree species fail to persist.
Resumo:
The progressive ageing of population has turned the mild cognitive impairment (MCI) into a prevalent disease suffered by elderly. Consequently, the spatial disorientation has become a significant problem for older people and their caregivers. The ambient-assisted living applications are offering location-based services for empowering elderly to go outside and encouraging a greater independence. Therefore, this paper describes the design and technical evaluation of a location-awareness service enabler aimed at supporting and managing probable wandering situations of a person with MCI. Through the presence capabilities of the IP multimedia subsystem (IMS) architecture, the service will alert patient's contacts if a hazardous situation is detected depending on his location. Furthermore, information about the older person's security areas has been included in the user profile managed by IMS. In doing so, the service enabler introduced contribute to “context-awareness” paradigm allowing the adaptation and personalization of services depending on user's context and specific conditions or preferences.
Resumo:
The theoretical basis for evaluating shear strength in rock joints is presented and used to derive an equation that governs the relationship between tangential and normal stress on the joint during situations of slippage between the joint faces. The dependent variables include geometric dilatancy, the instantaneous friction angle, and a parameter that considers joint surface roughness. The effect roughness is studied, and the aforementioned formula is used to analyse joints under different conditions. A mathematical expression is deduced that explains Barton's value for the joint roughness coefficient (JRC) according to the roughness geometry. In particular, when the Hoek and Brown failure criterion is used for a rock in the contact with the surface roughness plane, it is possible to determine the shear strength of the joint as a function of the relationship between the uniaxial compressive strength of the wall with the normal stress acting on the wall. Finally, theoretical results obtained for the geometry of a three-dimensional joint are compared with those of the Barton's formulation
Resumo:
The paper describes some relevant results of an on-going research aiming to elaborate a methodology to help the mobility management in natural parks, compatible with their protection missions: it has been developed a procedure to reproduce the mobility-environment relationships in various operational conditions. The final purpose is the identification of: a) the effects of various choices in transport planning, both at long term and strategic level; b) the most effective policies of mobility management. The work is articulated in the following steps: 1) definition of protected area on the basis of ecological and socio-economic criteria and legislative constraints; 2) analysis of mobility needs in the protected areas; 3) reconstruction of the state of the art of mobility management in natural parks at European level; 4) analysis of used traffic flows measurement methods; 5) analysis of environmental impacts due to transport systems modelling (air pollution and noise only); 6) identification of mitigation measures to be potentially applied. The whole methodology has been tested and validated on Italian case studies: i) the concerned area has been zoned according to the land-use peculiarities; ii) the local situations of transport infrastructure (roads and parking), services (public transport systems) and rules (traffic regulations) have been mapped with references to physical and functional attributes; iii) the mobility, both systematic and touristic, has been represented in an origin-destination matrix. By means of an assignment model the flows have been distributed and the corresponding average speeds to quantify gaseous and noise emissions was calculated, the criticalities in the reference scenario have been highlighted, as well as some alternative scenarios, including both operational and infrastructural measures have been identified. The comparison between projects and reference scenario allowed the quantification of effects (variation of emissions) for each scenario and a selection of the most effective management actions to be taken.
Resumo:
The final purpose is the identification of: a) the effects of various choices in transport planning, both at long term and strategic level; b) the most effective policies of mobility management. The preliminary work was articulated in the following steps: 1) definition of protected area on the basis of ecological and socio-economic criteria and legislative constraints; 2) analysis of mobility needs in the protected areas; 3) reconstruction of the state of the art of mobility management in natural parks at European level; 4) analysis of used traffic flows measurement methods; 5) analysis of environmental impacts due to transport systems modelling (limited to air pollution and noise); 6) identification of mitigation measures to the potentially applied. The whole methodology has been firstly tested on the case study of the National Park of ?Gran Sasso and Monti della Laga? and further validated on the National Park of ?Gargano?, both located Italy: i) the concerned area has been zoned according to the land-use peculiarities; ii) the local situations of transport infrastructure (roads and parking), services (public transport systems) and rules (traffic regulations) have been mapped with references to physical and functional attributes; iii) the mobility, both systematic and touristic, has been synthetically represented in an origin-destination matrix. By means of an assignment model it has been determined the distribution of flows and the corresponding average speeds to quantify gaseous and noise emissions. On this basis the environmental criticalities in the reference scenario have been highlighted, as well as some alternative scenarios including both operational and infrastructural measures have been identified. The comparison between the projects and the reference scenario allowed the quantification of the effects (variation of emissions) for each scenario and a selection of the most effective management actions to be taken.
Resumo:
In this work, various turbulent solutions of the two-dimensional (2D) and three-dimensional compressible Reynolds averaged Navier?Stokes equations are analyzed using global stability theory. This analysis is motivated by the onset of flow unsteadiness (Hopf bifurcation) for transonic buffet conditions where moderately high Reynolds numbers and compressible effects must be considered. The buffet phenomenon involves a complex interaction between the separated flow and a shock wave. The efficient numerical methodology presented in this paper predicts the critical parameters, namely, the angle of attack and Mach and Reynolds numbers beyond which the onset of flow unsteadiness appears. The geometry, a NACA0012 profile, and flow parameters selected reproduce situations of practical interest for aeronautical applications. The numerical computation is performed in three steps. First, a steady baseflow solution is obtained; second, the Jacobian matrix for the RANS equations based on a finite volume discretization is computed; and finally, the generalized eigenvalue problem is derived when the baseflow is linearly perturbed. The methodology is validated predicting the 2D Hopf bifurcation for a circular cylinder under laminar flow condition. This benchmark shows good agreement with the previous published computations and experimental data. In the transonic buffet case, the baseflow is computed using the Spalart?Allmaras turbulence model and represents a mean flow where the high frequency content and length scales of the order of the shear-layer thickness have been averaged. The lower frequency content is assumed to be decoupled from the high frequencies, thus allowing a stability analysis to be performed on the low frequency range. In addition, results of the corresponding adjoint problem and the sensitivity map are provided for the first time for the buffet problem. Finally, an extruded three-dimensional geometry of the NACA0012 airfoil, where all velocity components are considered, was also analyzed as a Triglobal stability case, and the outcoming results were compared to the previous 2D limited model, confirming that the buffet onset is well detected.
Resumo:
The technique of Abstract Interpretation has allowed the development of very sophisticated global program analyses which are at the same time provably correct and practical. We present in a tutorial fashion a novel program development framework which uses abstract interpretation as a fundamental tool. The framework uses modular, incremental abstract interpretation to obtain information about the program. This information is used to validate programs, to detect bugs with respect to partial specifications written using assertions (in the program itself and/or in system libraries), to generate and simplify run-time tests, and to perform high-level program transformations such as multiple abstract specialization, parallelization, and resource usage control, all in a provably correct way. In the case of validation and debugging, the assertions can refer to a variety of program points such as procedure entry, procedure exit, points within procedures, or global computations. The system can reason with much richer information than, for example, traditional types. This includes data structure shape (including pointer sharing), bounds on data structure sizes, and other operational variable instantiation properties, as well as procedure-level properties such as determinacy, termination, nonfailure, and bounds on resource consumption (time or space cost). CiaoPP, the preprocessor of the Ciao multi-paradigm programming system, which implements the described functionality, will be used to illustrate the fundamental ideas.
Resumo:
En las últimas décadas se han producido importantes avances tecnológicos, lo que ha producido un crecimiento importante de las Redes Inalámbricas de Sensores (RIS), conocidas en inglés como Wireless Sensor Networks (WSN). Estas redes están formadas por un conjunto de pequeños nodos o también, conocidos como motas, compuestos por diversos tipos de sensores. Las Redes Inalámbricas de Sensores pueden resultar muy útiles en entornos donde el despliegue de redes cableadas, formadas por ordenadores, encaminadores u otros dispositivos de red no sea posible. Sin embargo, este tipo de redes presentan una serie de carencias o problemas que dificultan, en ocasiones, su implementación y despliegue. Este Proyecto Fin de Carrera tiene como principales objetivos: diseñar e implementar un agente que haga uso de la tecnología Bluetooth para que se pueda comunicar tanto con la arquitectura orientada a servicios, vía radio, como con el módulo Bioharness para obtener parámetros fisiológicos; ofrecer una serie de servicios simples a la Red Inalámbrica de Sensores; diseñar un algoritmo para un sistema de alarmas; realizar e implementar una pasarela entre protocolos que usen el estándar IEEE802.15.4 (ZigBee) y el estándar IEEE802.15.1 de la Tecnología Bluetooth. Por último, implementar una aplicación Android para el reloj WiMM y que este pueda recibir alarmas en tiempo real a través del la Interfaz Bluetooth. Para lograr estos objetivos, en primer lugar realizaremos un estudio del Estado del Arte de las Redes Inalámbricas de Sensores, con el fin de estudiar su arquitectura, el estándar Bluetooth y los dispositivos Bluetooth que se han utilizado en este Proyecto. Seguidamente, describiremos detalladamente el firmware iWRAP versión 4, centrándonos en sus modos de operación, comandos AT y posibles errores que puedan ocurrir. A continuación, se describirá la arquitectura y la especificación nSOM, para adentrarnos en la arquitectura orientada a servicios. Por último, ejecutaremos la fase de validación del sistema y se analizarán los resultados obtenidos durante la fase de pruebas. ABSTRACT In last decades there have been significant advances in technology, which has resulted in important growth of Wireless Sensor Networks (WSN). These networks consist of a small set of nodes, also known as spots; equipped with various types of sensors. Wireless Sensor Networks can be very useful in environments where deployment of wired networks, formed by computers, routers or other network devices is not possible. However, these networks have a number of shortcomings or challenges to, sometimes, their implementation and deployment. The main objectives of this Final Project are to design and implement an agent that makes use of Bluetooth technology so you can communicate with both the service-oriented architecture, via radio, as with Bioharness module for physiological parameters; offer simple services to Wireless Sensor Network, designing an algorithm for an alarm system, make and implement a gateway between protocols using the standard IEEE802.15.4 (ZigBee) and IEEE802.15.1 standard Bluetooth Technology. Finally, implement an Android application for WiMM watch that can receive real-time alerts through the Bluetooth interface. In order to achieve these objectives, firstly we are going to carry out a study of the State of the Art in Wireless Sensor Network, where we study the architecture, the Bluetooth standard and Bluetooth devices that have been used in this project. Then, we will describe in detail the iWRAP firmware version 4, focusing on their operation modes, AT commands and errors that may occur. Therefore, we will describe the architecture and specification nSOM, to enter into the service-oriented architecture. Finally, we will execute the phase of validation of the system in a real application scenario, analyzing the results obtained during the testing phase.
Resumo:
The technique of Abstract Interpretation has allowed the development of very sophisticated global program analyses which are at the same time provably correct and practical. We present in a tutorial fashion a novel program development framework which uses abstract interpretation as a fundamental tool. The framework uses modular, incremental abstract interpretation to obtain information about the program. This information is used to validate programs, to detect bugs with respect to partial specifications written using assertions (in the program itself and/or in system librarles), to genérate and simplify run-time tests, and to perform high-level program transformations such as múltiple abstract specialization, parallelization, and resource usage control, all in a provably correct way. In the case of validation and debugging, the assertions can refer to a variety of program points such as procedure entry, procedure exit, points within procedures, or global computations. The system can reason with much richer information than, for example, traditional types. This includes data structure shape (including pointer sharing), bounds on data structure sizes, and other operational variable instantiation properties, as well as procedure-level properties such as determinacy, termination, non-failure, and bounds on resource consumption (time or space cost). CiaoPP, the preprocessor of the Ciao multi-paradigm programming system, which implements the described functionality, will be used to illustrate the fundamental ideas.
Resumo:
We present in a tutorial fashion CiaoPP, the preprocessor of the Ciao multi-paradigm programming system, which implements a novel program development framework which uses abstract interpretation as a fundamental tool. The framework uses modular, incremental abstract interpretation to obtain information about the program. This information is used to validate programs, to detect bugs with respect to partial specifications written using assertions (in the program itself and/or in system libraries), to generate and simplify run-time tests, and to perform high-level program transformations such as multiple abstract specialization, parallelization, and resource usage control, all in a provably correct way. In the case of validation and debugging, the assertions can refer to a variety of program points such as procedure entry, procedure exit, points within procedures, or global computations. The system can reason with much richer information than, for example, traditional types. This includes data structure shape (including pointer sharing), bounds on data structure sizes, and other operational variable instantiation properties, as well as procedure-level properties such as determinacy, termination, non-failure, and bounds on resource consumption (time or space cost).
Resumo:
¿Qué son los TRAJES ESPACIALES? El término Trajes Espaciales da nombre al “equipo de inmersión” 1 necesario para garantizar las condiciones de habitabilidad en determinados entornos o circunstancias. En diferentes coyunturas sociales, políticas o ambientales el formato convencional de la arquitectura se vuelve limitado o poco eficaz. Determinadas configuraciones de “vida a la intemperie” 2, asociadas a necesidades de protección, energía, comunicación, socialización…, en situaciones de alta emancipación e itinerancia, solicitan una reflexión sobre la posible portabilidad, o más concretamente, sobre la idoneidad del uso 3 de las condiciones arquitectónicas. La tesis pretende acotar o definir un no reconocido ámbito de los recursos proyectuales del arquitecto dirigido a la confección de las más cercanas envolventes corporales entendidas como elementos arquitectónicos. Casa y vestimenta, citando a Marshall McLuhan, se identifican en un discurso que entiende ambas esferas como “extensiones de la piel” 4 que garantizan el control energético y la definición social del sujeto que las habita. En determinados momentos el arquitecto ha tenido que desestimar como principal herramienta de trabajo la construcción de edificios, para abordar ciertas demandas sociales. La tesis pretende demostrar cómo el diseño de trajes ha sido en ocasiones una estrategia proyectual del repertorio de la arquitectura. Su aportación es la de abordar el mundo de la vestimenta más allá del simple ejercicio estilístico, defendiendo estas construcciones como un elemento capaz de hacer habitable un determinado entorno. Este acercamiento ha permitido a los arquitectos ensayar en los trajes lo que posteriormente desarrollarían en sus edificios. Temas tratados por la arquitectura como higienismo, ornamento, estandarización, pliegue… han encontrado en la escala de la vestimenta su expresión más pura. El diseño de estos trajes, su pertinencia y su confección como parte del proyecto arquitectónico, conformará el hilo conductor de esta tesis. ABSTRACT The term spacesuits tries to define the “diving equipment” 5 necessary to ensure the living conditions in certain environments or circumstances. In specific social, political or environmental circumstances, the architectural standard format becomes limited or ineffective. Some configurations of “life outdoor” 6, associated with protection, energy, communication and socialization needs, in situations of high emancipation and roaming, seek a reflection on the possible portability, or more specifically, on the appropriateness of wearing the architectural features. The thesis aims to limit or define an unrecognized field from the resources of the architect focused on body emvelopes as architectural elements. House and clothing, quoting Marshall McLuhan, are matched in a speech that understand both spheres as “extensions of the skins” 7, to ensure energy control and social definition of the subject who inhabit them. At times, the architect has had to dismiss the construction of buildings as the main tool for working, to address certain social demands. The thesis aims to demonstrate how the costume design is sometimes a projectual strategy in the repertoire of architecture. Its contribution splits with Fashion as a mere stylistic exercise, defending the dress as an artefact capable of making livable a certain environment. This approach has allowed architects to explore at costumes what they develope in their buildings later. Topics covered by the architecture as hygienism, ornament, standardization, folding... have found in the scale of the dress its purest expression. The design of these suits, their techniques and their relevance as part of the architectural project, will form the core of this thesis.
Resumo:
The problem of recurring concepts in data stream classification is a special case of concept drift where concepts may reappear. Although several existing methods are able to learn in the presence of concept drift, few consider contextual information when tracking recurring concepts. Nevertheless, in many real-world scenarios context information is available and can be exploited to improve existing approaches in the detection or even anticipation of recurring concepts. In this work, we propose the extension of existing approaches to deal with the problem of recurring concepts by reusing previously learned decision models in situations where concepts reappear. The different underlying concepts are identified using an existing drift detection method, based on the error-rate of the learning process. A method to associate context information and learned decision models is proposed to improve the adaptation to recurring concepts. The method also addresses the challenge of retrieving the most appropriate concept for a particular context. Finally, to deal with situations of memory scarcity, an intelligent strategy to discard models is proposed. The experiments conducted so far, using synthetic and real datasets, show promising results and make it possible to analyze the trade-off between the accuracy gains and the learned models storage cost.
Resumo:
La determinación del origen de un material utilizado por el hombre en la prehistoria es de suma importancia en el ámbito de la arqueología. En los últimos años, los estudios de procedencia han utilizado técnicas que suelen ser muy precisas pero con el inconveniente de ser metodologías de carácter destructivo. El fenómeno de la minería a gran escala es una de las características que acompaña al Neolítico, de ahí que la revolución correspondiente a este periodo sea una de las etapas más importantes para la humanidad. El yacimiento arqueológico de Casa Montero es una mina de sílex neolítica ubicada en la Península Ibérica, de gran importancia por su antigüedad y su escala productiva. Este sitio arqueológico corresponde a una cantera de explotación de rocas silícicas desarrollada en el periodo neolítico en la que solamente se han encontrado los desechos de la extracción minera, lo cual incrementa la variabilidad de las muestras analizadas, de las que se desconoce su contexto económico, social y cultural. Es de gran interés arqueológico saber por qué esos grupos neolíticos explotaban de forma tan intensiva determinados tipos de material y cuál era el destino de la cadena productiva del sílex. Además, por ser una excavación de rescate, que ha tenido que procesar varias toneladas de material, en un tiempo relativamente corto, requiere de métodos expeditivos de clasificación y manejo de dicho material. Sin embargo,la implementación de cualquier método de clasificación debe evitar la alteración o modificación de la muestra,ya que,estudios previos sobre caracterización de rocas silícicas tienen el inconveniente de alterar parcialmente el objeto de estudio. Por lo que el objetivo de esta investigación fue la modelización del registro y procesamiento de datos espectrales adquiridos de rocas silícicas del yacimiento arqueológico de Casa Montero. Se implementó la metodología para el registro y procesamiento de datos espectrales de materiales líticos dentro del contexto arqueológico. Lo anterior se ha conseguido con la aplicación de modelos de análisis espectral, algoritmos de suavizado de firmas espectrales, reducción de la dimensionalidad de las características y la aplicación de métodos de clasificación, tanto de carácter vectorial como raster. Para la mayoría de los procedimientos se ha desarrollado una aplicación informática validada tanto por los propios resultados obtenidos como comparativamente con otras aplicaciones. Los ensayos de evaluación de la metodología propuesta han permitido comprobar la eficacia de los métodos. Por lo que se concluye que la metodología propuesta no solo es útil para materiales silícicos, sino que se puede generalizar en aquellos procesos donde la caracterización espectral puede ser relevante para la clasificación de materiales que no deban ser alterados, además, permite aplicarla a gran escala, dado que los costes de ejecución son mínimos si se comparan con los de métodos convencionales. Así mismo, es de destacar que los métodos propuestos, representan la variabilidad del material y permiten relacionarla con el estado del yacimiento, según su contenido respecto de las tipologías de la cadena operativa. ABSTRACT: The determination of the origin of a material used by man in prehistory is very important in the field of archaeology. In recent years the provenance studies have used techniques that tend to be very precise but with the drawback of being destructive methodologies. The phenomenon of mining on a large scale is a feature that accompanies the Neolithic period; the Neolithic revolution is one of the most important periods of humanity. The archaeological site of Casa Montero is a Neolithic flint mine located in the Iberian Peninsula of great importance for its antiquity and its scale. This archaeological site corresponds to a quarry exploitation of silicic rocks developed in the Neolithic period, in which only found debris from mining, which increases the variability of the samples analyzed, including their economic, social and cultural context is unknown. It is of great archaeological interest to know why these Neolithic groups exploited as intensive certain types of material and what the final destination of flint was in the productive chain. In addition, being an excavation of rescue that had to process several tons of material in a relatively short time requires expeditious methods of classification and handling of the material. However, the implementation of any method of classification should avoid the alteration or modification of the sample, since previous studies on characterization of silicic rocks have the disadvantage of destroying or partially modify the object of study. So the objective of this research wasthe modeling of the registration and processing of acquired spectral data of silicic rocks of the archaeological site of Casa Montero. The methodology implemented for modeling the registration and processing of existing spectral data of lithic materials within the archaeological context, was presented as an alternative to the conventional classification methods (methods destructive and expensive) or subjective methods that depend on the experience of the expert. The above has been achieved with the implementation of spectral analysis models, smoothing of spectral signatures and the dimensionality reduction algorithms. Trials of validation of the proposed methodology allowed testing the effectiveness of the methods in what refers to the spectral characterization of siliceous materials of Casa Montero. Is remarkable the algorithmic contribution of the signal filtering, improve of quality and reduction of the dimensionality, as well the proposal of using raster structures for efficient storage and analysis of spectral information. For which it is concluded that the proposed methodology is not only useful for siliceous materials, but it can be generalized in those processes where spectral characterization may be relevant to the classification of materials that must not be altered, also allows to apply it on a large scale, given that the implementation costs are minimal when compared with conventional methods.