Outcomes and cost effectiveness of treating type 2 diabetes with a nurse case manager following treatment algorithms versus primary care physicians

Background. Diabetes places a significant burden on the health care system. Reduction in blood glucose levels (HbA1c) reduces the risk of complications; however, little is known about the impact of disease management programs on medical costs for patients with diabetes. In 2001, economic costs associated with diabetes totaled $100 billion, and indirect costs totaled $54 billion. ^ Objective. To compare outcomes of nurse case management by treatment algorithms with conventional primary care for glycemic control and cardiovascular risk factors in type 2 diabetic patients in a low-income Mexican American community-based setting, and to compare the cost effectiveness of the two programs. Patient compliance was also assessed. ^ Research design and methods. An observational group-comparison to evaluate a treatment intervention for type 2 diabetes management was implemented at three out-patient health facilities in San Antonio, Texas. All eligible type 2 diabetic patients attending the clinics during 1994���1996 became part of the study. Data were obtained from the study database, medical records, hospital accounting, and pharmacy cost lists, and entered into a computerized database. Three groups were compared: a Community Clinic Nurse Case Manager (CC-TA) following treatment algorithms, a University Clinic Nurse Case Manager (UC-TA) following treatment algorithms, and Primary Care Physicians (PCP) following conventional care practices at a Family Practice Clinic. The algorithms provided a disease management model specifically for hyperglycemia, dyslipidemia, hypertension, and microalbuminuria that progressively moved the patient toward ideal goals through adjustments in medication, self-monitoring of blood glucose, meal planning, and reinforcement of diet and exercise. Cost effectiveness of hemoglobin AI, final endpoints was compared. ^ Results. There were 358 patients analyzed: 106 patients in CC-TA, 170 patients in UC-TA, and 82 patients in PCP groups. Change in hemoglobin A1c (HbA1c) was the primary outcome measured. HbA1c results were presented at baseline, 6 and 12 months for CC-TA (10.4%, 7.1%, 7.3%), UC-TA (10.5%, 7.1%, 7.2%), and PCP (10.0%, 8.5%, 8.7%). Mean patient compliance was 81%. Levels of cost effectiveness were significantly different between clinics. ^ Conclusion. Nurse case management with treatment algorithms significantly improved glycemic control in patients with type 2 diabetes, and was more cost effective. ^

The Nature of Genetic Engineering and the Uses and Potential Abuses of Biotechnology

Over the past decade the topic of genetic engineering has been has been readily debated in the media, but often these debates consist of political rhetoric and fail to offer objective information on the methods and the potential benefits to human health and their environment. In truth, humans have been manipulating the genomes of organisms for thousands of years, and it has been an evolution of scientific knowledge that has led to the more precise methods of genetic engineering. This paper discusses how scientists utilize natural processes to alter the genetic constituents of both prokaryotic and eukaryotic organisms, benefits to human health and the environment, as well as potential misuses of biotechnology such as bioterrorism.

Modeling Techniques for the High-Resolution Interpretation of Cryo-Electron Microscopy Reconstructions

Essential biological processes are governed by organized, dynamic interactions between multiple biomolecular systems. Complexes are thus formed to enable the biological function and get dissembled as the process is completed. Examples of such processes include the translation of the messenger RNA into protein by the ribosome, the folding of proteins by chaperonins or the entry of viruses in host cells. Understanding these fundamental processes by characterizing the molecular mechanisms that enable then, would allow the (better) design of therapies and drugs. Such molecular mechanisms may be revealed trough the structural elucidation of the biomolecular assemblies at the core of these processes. Various experimental techniques may be applied to investigate the molecular architecture of biomolecular assemblies. High-resolution techniques, such as X-ray crystallography, may solve the atomic structure of the system, but are typically constrained to biomolecules of reduced flexibility and dimensions. In particular, X-ray crystallography requires the sample to form a three dimensional (3D) crystal lattice which is technically di���cult, if not impossible, to obtain, especially for large, dynamic systems. Often these techniques solve the structure of the different constituent components within the assembly, but encounter difficulties when investigating the entire system. On the other hand, imaging techniques, such as cryo-electron microscopy (cryo-EM), are able to depict large systems in near-native environment, without requiring the formation of crystals. The structures solved by cryo-EM cover a wide range of resolutions, from very low level of detail where only the overall shape of the system is visible, to high-resolution that approach, but not yet reach, atomic level of detail. In this dissertation, several modeling methods are introduced to either integrate cryo-EM datasets with structural data from X-ray crystallography, or to directly interpret the cryo-EM reconstruction. Such computational techniques were developed with the goal of creating an atomic model for the cryo-EM data. The low-resolution reconstructions lack the level of detail to permit a direct atomic interpretation, i.e. one cannot reliably locate the atoms or amino-acid residues within the structure obtained by cryo-EM. Thereby one needs to consider additional information, for example, structural data from other sources such as X-ray crystallography, in order to enable such a high-resolution interpretation. Modeling techniques are thus developed to integrate the structural data from the different biophysical sources, examples including the work described in the manuscript I and II of this dissertation. At intermediate and high-resolution, cryo-EM reconstructions depict consistent 3D folds such as tubular features which in general correspond to alpha-helices. Such features can be annotated and later on used to build the atomic model of the system, see manuscript III as alternative. Three manuscripts are presented as part of the PhD dissertation, each introducing a computational technique that facilitates the interpretation of cryo-EM reconstructions. The first manuscript is an application paper that describes a heuristics to generate the atomic model for the protein envelope of the Rift Valley fever virus. The second manuscript introduces the evolutionary tabu search strategies to enable the integration of multiple component atomic structures with the cryo-EM map of their assembly. Finally, the third manuscript develops further the latter technique and apply it to annotate consistent 3D patterns in intermediate-resolution cryo-EM reconstructions. The first manuscript, titled An assembly model for Rift Valley fever virus, was submitted for publication in the Journal of Molecular Biology. The cryo-EM structure of the Rift Valley fever virus was previously solved at 27��-resolution by Dr. Freiberg and collaborators. Such reconstruction shows the overall shape of the virus envelope, yet the reduced level of detail prevents the direct atomic interpretation. High-resolution structures are not yet available for the entire virus nor for the two different component glycoproteins that form its envelope. However, homology models may be generated for these glycoproteins based on similar structures that are available at atomic resolutions. The manuscript presents the steps required to identify an atomic model of the entire virus envelope, based on the low-resolution cryo-EM map of the envelope and the homology models of the two glycoproteins. Starting with the results of the exhaustive search to place the two glycoproteins, the model is built iterative by running multiple multi-body refinements to hierarchically generate models for the different regions of the envelope. The generated atomic model is supported by prior knowledge regarding virus biology and contains valuable information about the molecular architecture of the system. It provides the basis for further investigations seeking to reveal different processes in which the virus is involved such as assembly or fusion. The second manuscript was recently published in the of Journal of Structural Biology (doi:10.1016/j.jsb.2009.12.028) under the title Evolutionary tabu search strategies for the simultaneous registration of multiple atomic structures in cryo-EM reconstructions. This manuscript introduces the evolutionary tabu search strategies applied to enable a multi-body registration. This technique is a hybrid approach that combines a genetic algorithm with a tabu search strategy to promote the proper exploration of the high-dimensional search space. Similar to the Rift Valley fever virus, it is common that the structure of a large multi-component assembly is available at low-resolution from cryo-EM, while high-resolution structures are solved for the different components but lack for the entire system. Evolutionary tabu search strategies enable the building of an atomic model for the entire system by considering simultaneously the different components. Such registration indirectly introduces spatial constrains as all components need to be placed within the assembly, enabling the proper docked in the low-resolution map of the entire assembly. Along with the method description, the manuscript covers the validation, presenting the benefit of the technique in both synthetic and experimental test cases. Such approach successfully docked multiple components up to resolutions of 40��. The third manuscript is entitled Evolutionary Bidirectional Expansion for the Annotation of Alpha Helices in Electron Cryo-Microscopy Reconstructions and was submitted for publication in the Journal of Structural Biology. The modeling approach described in this manuscript applies the evolutionary tabu search strategies in combination with the bidirectional expansion to annotate secondary structure elements in intermediate resolution cryo-EM reconstructions. In particular, secondary structure elements such as alpha helices show consistent patterns in cryo-EM data, and are visible as rod-like patterns of high density. The evolutionary tabu search strategy is applied to identify the placement of the different alpha helices, while the bidirectional expansion characterizes their length and curvature. The manuscript presents the validation of the approach at resolutions ranging between 6 and 14��, a level of detail where alpha helices are visible. Up to resolution of 12 ��, the method measures sensitivities between 70-100% as estimated in experimental test cases, i.e. 70-100% of the alpha-helices were correctly predicted in an automatic manner in the experimental data. The three manuscripts presented in this PhD dissertation cover different computation methods for the integration and interpretation of cryo-EM reconstructions. The methods were developed in the molecular modeling software Sculptor (http://sculptor.biomachina.org) and are available for the scientific community interested in the multi-resolution modeling of cryo-EM data. The work spans a wide range of resolution covering multi-body refinement and registration at low-resolution along with annotation of consistent patterns at high-resolution. Such methods are essential for the modeling of cryo-EM data, and may be applied in other fields where similar spatial problems are encountered, such as medical imaging.

Integration of III-V materials on Silicon Substrates for Multi-junction Solar Cell Applications

The work presented here aims to reduce the cost of multijunction solar cell technology by developing ways to manufacture them on cheap substrates such as silicon. In particular, our main objective is the growth of III-V semiconductors on silicon substrates for photovoltaic applications. The goal is to create a GaAsP/Si virtual substrates onto which other III-V cells could be integrated with an interesting efficiency potential. This technology involves several challenges due to the difficulty of growing III-V materials on silicon. In this paper, our first work done aimed at developing such structure is presented. It was focused on the development of phosphorus diffusion models on silicon and on the preparation of an optimal silicon surface to grow on it III-V materials.

A review of estimation of distribution algorithms in bioinformatics

Evolutionary search algorithms have become an essential asset in the algorithmic toolbox for solving high-dimensional optimization problems in across a broad range of bioinformatics problems. Genetic algorithms, the most well-known and representative evolutionary search technique, have been the subject of the major part of such applications. Estimation of distribution algorithms (EDAs) offer a novel evolutionary paradigm that constitutes a natural and attractive alternative to genetic algorithms. They make use of a probabilistic model, learnt from the promising solutions, to guide the search process. In this paper, we set out a basic taxonomy of EDA techniques, underlining the nature and complexity of the probabilistic model of each EDA variant. We review a set of innovative works that make use of EDA techniques to solve challenging bioinformatics problems, emphasizing the EDA paradigm's potential for further research in this domain.

Decentralized multi-tasks distribution in heterogeneous robot teams by means of ant colony optimization and learning automata

This paper focuses on the general problem of coordinating multiple robots. More specifically, it addresses the self-election of heterogeneous specialized tasks by autonomous robots. In this paper we focus on a specifically distributed or decentralized approach as we are particularly interested on decentralized solution where the robots themselves autonomously and in an individual manner, are responsible of selecting a particular task so that all the existing tasks are optimally distributed and executed. In this regard, we have established an experimental scenario to solve the corresponding multi-tasks distribution problem and we propose a solution using two different approaches by applying Ant Colony Optimization-based deterministic algorithms as well as Learning Automata-based probabilistic algorithms. We have evaluated the robustness of the algorithm, perturbing the number of pending loads to simulate the robot���s error in estimating the real number of pending tasks and also the dynamic generation of loads through time. The paper ends with a critical discussion of experimental results.

Response threshold models and stochastic learning automata for self-coordination of heterogeneous multi-task distribution in multi-robot systems.

This paper focuses on the general problem of coordinating multiple robots. More specifically, it addresses the self-selection of heterogeneous specialized tasks by autonomous robots. In this paper we focus on a specifically distributed or decentralized approach as we are particularly interested in a decentralized solution where the robots themselves autonomously and in an individual manner, are responsible for selecting a particular task so that all the existing tasks are optimally distributed and executed. In this regard, we have established an experimental scenario to solve the corresponding multi-task distribution problem and we propose a solution using two different approaches by applying Response Threshold Models as well as Learning Automata-based probabilistic algorithms. We have evaluated the robustness of the algorithms, perturbing the number of pending loads to simulate the robot���s error in estimating the real number of pending tasks and also the dynamic generation of loads through time. The paper ends with a critical discussion of experimental results.

Application of PZT and FBG impedance sensors for structural health monitoring of reinforced concrete beams strengthened with FRP composite materials

Esta Tesis tiene como objetivo principal el desarrollo de m��todos de identificaci��n del da��o que sean robustos y fiables, enfocados a sistemas estructurales experimentales, fundamentalmente a las estructuras de hormig��n armado reforzadas externamente con bandas fibras de pol��meros reforzados (FRP). El modo de fallo de este tipo de sistema estructural es cr��tico, pues generalmente es debido a un despegue repentino y fr��gil de la banda del refuerzo FRP originado en grietas intermedias causadas por la flexi��n. La detecci��n de este despegue en su fase inicial es fundamental para prevenir fallos futuros, que pueden ser catastr��ficos. Inicialmente, se lleva a cabo una revisi��n del m��todo de la Impedancia Electro-Mec��nica (EMI), de cara a exponer sus capacidades para la detecci��n de da��o. Una vez la tecnolog��a apropiada es seleccionada, lo que incluye un analizador de impedancias as�� como novedosos sensores PZT para monitorizaci��n inteligente, se ha dise��ado un procedimiento autom��tico basado en los registros de impedancias de distintas estructuras de laboratorio. Bas��ndonos en el hecho de que las mediciones de impedancias son posibles gracias a una colocaci��n adecuada de una red de sensores PZT, la estimaci��n de la presencia de da��o se realiza analizando los resultados de distintos indicadores de da��o obtenidos de la literatura. Para que este proceso sea autom��tico y que no sean necesarios conocimientos previos sobre el m��todo EMI para realizar un experimento, se ha dise��ado e implementado un Interfaz Gr��fico de Usuario, transformando la medici��n de impedancias en un proceso f��cil e intuitivo. Se eval��a entonces el da��o a trav��s de los correspondientes ��ndices de da��o, intentando estimar no s��lo su severidad, sino tambi��n su localizaci��n aproximada. El desarrollo de estos experimentos en cualquier estructura genera grandes cantidades de datos que han de ser procesados, y algunas veces los ��ndices de da��o no son suficientes para una evaluaci��n completa de la integridad de una estructura. En la mayor��a de los casos se pueden encontrar patrones de da��o en los datos, pero no se tiene informaci��n a priori del estado de la estructura. En este punto, se ha hecho una importante investigaci��n en t��cnicas de reconocimiento de patrones particularmente en aprendizaje no supervisado, encontrando aplicaciones interesantes en el campo de la medicina. De ah�� surge una idea creativa e innovadora: detectar y seguir la evoluci��n del da��o en distintas estructuras como si se tratase de un c��ncer propag��ndose por el cuerpo humano. En ese sentido, las lecturas de impedancias se emplean como informaci��n intr��nseca de la salud de la propia estructura, de forma que se pueden aplicar las mismas t��cnicas que las empleadas en la investigaci��n del c��ncer. En este caso, se ha aplicado un algoritmo de clasificaci��n jer��rquica dado que ilustra adem��s la clasificaci��n de los datos de forma gr��fica, incluyendo informaci��n cualitativa y cuantitativa sobre el da��o. Se ha investigado la efectividad de este procedimiento a trav��s de tres estructuras de laboratorio, como son una viga de aluminio, una uni��n atornillada de aluminio y un bloque de hormig��n reforzado con FRP. La primera ayuda a mostrar la efectividad del m��todo en sencillos escenarios de da��o simple y m��ltiple, de forma que las conclusiones extra��das se aplican sobre los otros dos, dise��ados para simular condiciones de despegue en distintas estructuras. Demostrada la efectividad del m��todo de clasificaci��n jer��rquica de lecturas de impedancias, se aplica el procedimiento sobre las estructuras de hormig��n armado reforzadas con bandas de FRP objeto de esta tesis, detectando y clasificando cada estado de da��o. Finalmente, y como alternativa al anterior procedimiento, se propone un m��todo para la monitorizaci��n continua de la interfase FRP-Hormig��n, a trav��s de una red de sensores FBG permanentemente instalados en dicha interfase. De esta forma, se obtienen medidas de deformaci��n de la interfase en condiciones de carga continua, para ser implementadas en un modelo de optimizaci��n multiobjetivo, cuya soluci��n se haya por medio de una expansi��n multiobjetivo del m��todo Particle Swarm Optimization (PSO). La fiabilidad de este ��ltimo m��todo de detecci��n se investiga a trav��s de sendos ejemplos tanto num��ricos como experimentales. ABSTRACT This thesis aims to develop robust and reliable damage identification methods focused on experimental structural systems, in particular Reinforced Concrete (RC) structures externally strengthened with Fiber Reinforced Polymers (FRP) strips. The failure mode of this type of structural system is critical, since it is usually due to sudden and brittle debonding of the FRP reinforcement originating from intermediate flexural cracks. Detection of the debonding in its initial stage is essential thus to prevent future failure, which might be catastrophic. Initially, a revision of the Electro-Mechanical Impedance (EMI) method is carried out, in order to expose its capabilities for local damage detection. Once the appropriate technology is selected, which includes impedance analyzer as well as novel PZT sensors for smart monitoring, an automated procedure has been design based on the impedance signatures of several lab-scale structures. On the basis that capturing impedance measurements is possible thanks to an adequately deployed PZT sensor network, the estimation of damage presence is done by analyzing the results of different damage indices obtained from the literature. In order to make this process automatic so that it is not necessary a priori knowledge of the EMI method to carry out an experimental test, a Graphical User Interface has been designed, turning the impedance measurements into an easy and intuitive procedure. Damage is then assessed through the analysis of the corresponding damage indices, trying to estimate not only the damage severity, but also its approximate location. The development of these tests on any kind of structure generates large amounts of data to be processed, and sometimes the information provided by damage indices is not enough to achieve a complete analysis of the structural health condition. In most of the cases, some damage patterns can be found in the data, but none a priori knowledge of the health condition is given for any structure. At this point, an important research on pattern recognition techniques has been carried out, particularly on unsupervised learning techniques, finding interesting applications in the medicine field. From this investigation, a creative and innovative idea arose: to detect and track the evolution of damage in different structures, as if it were a cancer propagating through a human body. In that sense, the impedance signatures are used to give intrinsic information of the health condition of the structure, so that the same clustering algorithms applied in the cancer research can be applied to the problem addressed in this dissertation. Hierarchical clustering is then applied since it also provides a graphical display of the clustered data, including quantitative and qualitative information about damage. The performance of this approach is firstly investigated using three lab-scale structures, such as a simple aluminium beam, a bolt-jointed aluminium beam and an FRP-strengthened concrete specimen. The first one shows the performance of the method on simple single and multiple damage scenarios, so that the first conclusions can be extracted and applied to the other two experimental tests, which are designed to simulate a debonding condition on different structures. Once the performance of the impedance-based hierarchical clustering method is proven to be successful, it is then applied to the structural system studied in this dissertation, the RC structures externally strengthened with FRP strips, where the debonding failure in the interface between the FRP and the concrete is successfully detected and classified, proving thus the feasibility of this method. Finally, as an alternative to the previous approach, a continuous monitoring procedure of the FRP-Concrete interface is proposed, based on an FBGsensors Network permanently deployed within that interface. In this way, strain measurements can be obtained under controlled loading conditions, and then they are used in order to implement a multi-objective model updating method solved by a multi-objective expansion of the Particle Swarm Optimization (PSO) method. The feasibility of this last proposal is investigated and successfully proven on both numerical and experimental RC beams strengthened with FRP.

How should the sustainability of the location of dry ports be measured? A proposed methodology using Bayesian networks and multi-criteria decision analysis

The global economic structure, with its decentralized production and the consequent increase in freight traffic all over the world, creates considerable problems and challenges for the freight transport sector. This situation has led shipping to become the most suitable and cheapest way to transport goods. Thus, ports are configured as nodes with critical importance in the logistics supply chain as a link between two transport systems, sea and land. Increase in activity at seaports is producing three undesirable effects: increasing road congestion, lack of open space in port installations and a significant environmental impact on seaports. These adverse effects can be mitigated by moving part of the activity inland. Implementation of dry ports is a possible solution and would also provide an opportunity to strengthen intermodal solutions as part of an integrated and more sustainable transport chain, acting as a link between road and railway networks. In this sense, implementation of dry ports allows the separation of the links of the transport chain, thus facilitating the shortest possible routes for the lowest capacity and most polluting means of transport. Thus, the decision of where to locate a dry port demands a thorough analysis of the whole logistics supply chain, with the objective of transferring the largest volume of goods possible from road to more energy efficient means of transport, like rail or short-sea shipping, that are less harmful to the environment. However, the decision of where to locate a dry port must also ensure the sustainability of the site. Thus, the main goal of this article is to research the variables influencing the sustainability of dry port location and how this sustainability can be evaluated. With this objective, in this paper we present a methodology for assessing the sustainability of locations by the use of Multi-Criteria Decision Analysis (MCDA) and Bayesian Networks (BNs). MCDA is used as a way to establish a scoring, whilst BNs were chosen to eliminate arbitrariness in setting the weightings using a technique that allows us to prioritize each variable according to the relationships established in the set of variables. In order to determine the relationships between all the variables involved in the decision, giving us the importance of each factor and variable, we built a K2 BN algorithm. To obtain the scores of each variable, we used a complete cartography analysed by ArcGIS. Recognising that setting the most appropriate location to place a dry port is a geographical multidisciplinary problem, with significant economic, social and environmental implications, we consider 41 variables (grouped into 17 factors) which respond to this need. As a case of study, the sustainability of all of the 10 existing dry ports in Spain has been evaluated. In this set of logistics platforms, we found that the most important variables for achieving sustainability are those related to environmental protection, so the sustainability of the locations requires a great respect for the natural environment and the urban environment in which they are framed.

Development and improvement of protection-system algorithms for ground-fault detection and location in synchronous machines

Uno de los defectos m��s frecuentes en los generadores s��ncronos son los defectos a tierra tanto en el devanado estat��rico, como de excitaci��n. Se produce un defecto cuando el aislamiento el��ctrico entre las partes activas de cualquiera de estos devanados y tierra se reduce considerablemente o desaparece. La detecci��n de los defectos a tierra en ambos devanados es un tema ampliamente estudiado a nivel industrial. Tras la detecci��n y confirmaci��n de la existencia del defecto, dicha falta debe ser localizada a lo largo del devanado para su reparaci��n, para lo que habitualmente el rotor debe ser extra��do del estator. Esta operaci��n resulta especialmente compleja y cara. Adem��s, el hecho de limitar la corriente de defecto en ambos devanados provoca que el defecto no sea localizable visualmente, pues apenas existe da��o en el generador. Por ello, se deben aplicar t��cnicas muy laboriosas para localizar exactamente el defecto y poder as�� reparar el devanado. De cara a reducir el tiempo de reparaci��n, y con ello el tiempo en que el generador esta fuera de servicio, cualquier informaci��n por parte del rel�� de protecci��n acerca de la localizaci��n del defecto resultar��a de gran utilidad. El principal objetivo de esta tesis doctoral ha sido el desarrollo de nuevos algoritmos que permitan la estimaci��n de la localizaci��n de los defectos a tierra tanto en el devanado rot��rico como estat��rico de m��quinas s��ncronas. Respecto al devanado de excitaci��n, se ha presentado un nuevo m��todo de localizaci��n de defectos a tierra para generadores con excitaci��n est��tica. Este m��todo permite incluso distinguir si el defecto se ha producido en el devanado de excitaci��n, o en cualquiera de los componentes del sistema de excitaci��n, esto es, transformador de excitaci��n, conductores de alimentaci��n del rectificador controlado, etc. En caso de defecto a tierra en del devanado rot��rico, este m��todo proporciona una estimaci��n de su localizaci��n. Sin embargo, para poder obtener la localizaci��n del defecto, se precisa conocer el valor de resistencia de defecto. Por ello, en este trabajo se presenta adem��s un nuevo m��todo para la estimaci��n de este par��metro de forma precisa. Finalmente, se presenta un nuevo m��todo de detecci��n de defectos a tierra, basado en el criterio direccional, que complementa el m��todo de localizaci��n, permitiendo tener en cuenta la influencia de las capacidades a tierra del sistema. Estas capacidades resultan determinantes a la hora de localizar el defecto de forma adecuada. En relaci��n con el devanado estat��rico, en esta tesis doctoral se presenta un nuevo algoritmo de localizaci��n de defectos a tierra para generadores que dispongan de la protecci��n de faltas a tierra basada en la inyecci��n de baja frecuencia. Se ha propuesto un m��todo general, que tiene en cuenta todos los par��metros del sistema, as�� como una versi��n simplificada del m��todo para generadores con capacidades a tierra muy reducida, que podr��a resultar de f��cil implementaci��n en rel��s de protecci��n comercial. Los algoritmos y m��todos presentados se han validado mediante ensayos experimentales en un generador de laboratorio de 5 kVA, as�� como en un generador comercial de 106 MVA con resultados satisfactorios y prometedores. ABSTRACT One of the most common faults in synchronous generators is the ground fault in both the stator winding and the excitation winding. In case of fault, the insulation level between the active part of any of these windings and ground lowers considerably, or even disappears. The detection of ground faults in both windings is a very researched topic. The fault current is typically limited intentionally to a reduced level. This allows to detect easily the ground faults, and therefore to avoid damage in the generator. After the detection and confirmation of the existence of a ground fault, it should be located along the winding in order to repair of the machine. Then, the rotor has to be extracted, which is a very complex and expensive operation. Moreover, the fact of limiting the fault current makes that the insulation failure is not visually detectable, because there is no visible damage in the generator. Therefore, some laborious techniques have to apply to locate accurately the fault. In order to reduce the repair time, and therefore the time that the generator is out of service, any information about the approximate location of the fault would be very useful. The main objective of this doctoral thesis has been the development of new algorithms and methods to estimate the location of ground faults in the stator and in the rotor winding of synchronous generators. Regarding the excitation winding, a new location method of ground faults in excitation winding of synchronous machines with static excitation has been presented. This method allows even to detect if the fault is at the excitation winding, or in any other component of the excitation system: controlled rectifier, excitation transformer, etc. In case of ground fault in the rotor winding, this method provides an estimation of the fault location. However, in order to calculate the location, the value of fault resistance is necessary. Therefore, a new fault-resistance estimation algorithm is presented in this text. Finally, a new fault detection algorithm based on directional criterion is described to complement the fault location method. This algorithm takes into account the influence of the capacitance-to-ground of the system, which has a remarkable impact in the accuracy of the fault location. Regarding the stator winding, a new fault-location algorithm has been presented for stator winding of synchronous generators. This algorithm is applicable to generators with ground-fault protection based in low-frequency injection. A general algorithm, which takes every parameter of the system into account, has been presented. Moreover, a simplified version of the algorithm has been proposed for generators with especially low value of capacitance to ground. This simplified algorithm might be easily implementable in protective relays. The proposed methods and algorithms have been tested in a 5 kVA laboratory generator, as well as in a 106 MVA synchronous generator with satisfactory and promising results.

Dise��o para fabricaci��n digital: definici��n un��voca entre forma y fabricaci��n en arquitectura

La presente investigaci��n se inicia planteando el objetivo de identificar los par��metros geom��tricos que son exclusivos del proceso de generaci��n de la Forma y relacionarlos con los invariantes relacionados con la Fabricaci��n digital aplicada a la Arquitectura. Con ello se pretende recuperar la geometr��a como herramienta principal del proceso de Proyecto ampliando su ��mbito de actuaci��n al encontrar una relaci��n con los procesos de fabricaci��n digital. El primer cap��tulo describe los antecedentes y contexto hist��rico centr��ndose especialmente en la influencia de la capacidad de definir geometr��as complejas digitalmente mediante la aplicaci��n de algoritmos. En los primeros ejemplos la aproximaci��n del Arquitecto a proyectos con geometr��as complejas no eucl��deas a��n se emplea sin precisi��n en la comunicaci��n de la geometr��a ideada para su puesta en obra. Las t��cnicas constructivas obligan a asumir una tolerancia de desviaci��n entre proyecto y obra y la previsi��n del comportamiento de esa geometr��a no permite asegurar su comportamiento final. No ser�� hasta la introducci��n de herramientas CAD en el proceso de ideaci��n arquitect��nica cuando el Arquitecto se capacite para generar geometr��as no representables de forma anal��gica. Sin embargo, la imposibilidad de trasladar la geometr��a proyectada a la praxis constructiva impedir�� la plasmaci��n de un proceso completo, salvo en las contadas ocasiones que se recogen en este texto. ���El an��lisis cronol��gico de las referencias establece como aspecto esencial para la construcci��n de geometr��as complejas la capacidad primero para definir y comunicar de forma precisa e inequ��voca la geometr��a y despu��s la capacidad de analizar el desempe��o prestacional de dicha propuesta geom��trica���. La presente investigaci��n se inicia planteando el objetivo de identificar los par��metros geom��tricos que son exclusivos del proceso de generaci��n de la Forma y relacionarlos con los invariantes relacionados con la Fabricaci��n digital aplicada a la Arquitectura. Con ello se pretende recuperar la geometr��a como herramienta principal del proceso de Proyecto ampliando su ��mbito de actuaci��n al encontrar una relaci��n con los procesos de fabricaci��n digital. El primer cap��tulo describe los antecedentes y contexto hist��rico centr��ndose especialmente en la influencia de la capacidad de definir geometr��as complejas digitalmente mediante la aplicaci��n de algoritmos. En los primeros ejemplos la aproximaci��n del Arquitecto a proyectos con geometr��as complejas no eucl��deas a��n se emplea sin precisi��n en la comunicaci��n de la geometr��a ideada para su puesta en obra. Las t��cnicas constructivas obligan a asumir una tolerancia de desviaci��n entre proyecto y obra y la previsi��n del comportamiento de esa geometr��a no permite asegurar su comportamiento final. No ser�� hasta la introducci��n de herramientas CAD en el proceso de ideaci��n arquitect��nica cuando el Arquitecto se capacite para generar geometr��as no representables de forma anal��gica. Sin embargo, la imposibilidad de trasladar la geometr��a proyectada a la praxis constructiva impedir�� la plasmaci��n de un proceso completo, salvo en las contadas ocasiones que se recogen en este texto. ���El an��lisis cronol��gico de las referencias establece como aspecto esencial para la construcci��n de geometr��as complejas la capacidad primero para definir y comunicar de forma precisa e inequ��voca la geometr��a y despu��s la capacidad de analizar el desempe��o prestacional de dicha propuesta geom��trica���. Establecida la primera conclusi��n, el cap��tulo de contexto hist��rico contin��a enfoc��ndose sobre la aplicaci��n de las t��cnicas digitales en el Proceso de proyecto primero, y en la puesta en obra despu��s. Los casos de estudio identifican claramente como un punto de inflexi��n para la generaci��n de formas complejas mediante un software CAD el Museo Guggenheim de Bilbao en 1992. El motivo esencial para elegir este proyecto como el primer proyecto digital es el uso de la herramienta de definici��n digital de la geometr��a para su reproducci��n inequ��voca en obra. ���La revoluci��n digital ha aportado al Arquitecto la posibilidad de abandonar las tipolog��as arquitect��nicas basados en restricciones geom��tricas-constructivas. La aplicaci��n de t��cnicas de fabricaci��n digital ha permitido la capacidad de dise��ar con independencia del sistema constructivo y libertad formal. En este nuevo contexto las prestaciones suponen los nuevos l��mites conceptuales, ya que el acceso y disposici��n de la informaci��n del comportamiento de las alternativas que cada geometr��a conlleva demanda del Arquitecto la jerarquizaci��n de los objetivos y la formulaci��n en un conjunto coherente de par��metros���. Los proyectos que emplean herramientas digitales para la resoluci��n de las distintas etapas del proceso proyectual se ver��n incrementados de forma exponencial desde 1992 hasta nuestros d��as. A pesar del importante auge de las t��cnicas de dise��o asistido por ordenador el principal desaf��o sigue siendo la vinculaci��n de las geometr��as y materiales propuestos con las capacidades de las t��cnicas de manufactura y puesta en obra. El proceso de dise��o para fabricaci��n en un entorno digital es una tecnolog��a madura en otras industrias como la aeroespacial o la automovil��stica, incluso la de productos de consumo y decoraci��n, sin embargo en el sector de Construcci��n es un sistema inmaduro e inconexo. Las particularidades de la industria de la construcci��n a��n no han sido abordadas en su totalidad y las propuestas de investigaci��n realizadas en este ��mbito se han centrado hasta 2015 en partes del proceso y no en el proceso total. ���El principal obst��culo para la estandarizaci��n e implantaci��n globalizada de un proceso digital desde el origen de la forma hasta la construcci��n es la inexistencia de un protocolo integrado que integre las limitaciones de fabricaci��n, econ��micas y de puesta en obra junto a la evaluaci��n de desempe��o prestacional durante la fases iniciales de proyecto���. En el cap��tulo n��mero 3 se estudian los distintos procesos de generaci��n de la forma. Se propone una definici��n espec��fica para el ��mbito de la investigaci��n de ���forma��� en el entendemos que se incluye la envolvente exterior y el conjunto organizativo de espacios interiores conectados. Por lo tanto no es excluyente del interior. El objetivo de este estudio es analizar y clasificar los procesos para la generaci��n digital de formas en los distintos proyectos seleccionados como emblem��ticos de cada tipolog��a. Se concluye que la aproximaci��n a este proceso es muy variada y compleja, con aplicaci��n segregada y descoordinada entre los distintos agentes que han intervenir. En un proceso de generaci��n formal anal��gico los par��metros que intervienen son en parte conscientes y en parte inconscientes o aprendidos. El Arquitecto s��lo tiene control sobre la parte consciente de los par��metros a integrar en el dise��o, de acuerdo a sus conocimientos y capacidades ser�� capaz de manejar un n��mero limitado de par��metros. La parte aprendida permanece en el inconsciente y dirige el proceso anal��gico, aportando prejuicios est��ticos incorporados durante el proceso formativo y propio del entorno cultural. ���El empleo de herramientas digitales basadas en la evaluaci��n prestacional durante el proceso de selecci��n formal permite al Arquitecto conocer ���en tiempo real��� el desempe��o en el conjunto de prestaciones evaluadoras del conjunto de alternativas geom��tricas a la propuesta previamente definida por la intuici��n arquitect��nica. El proceso definido no persigue identificar una soluci��n ��ptima sino asistir al Arquitecto en el proceso de generaci��n de la forma mediante la evaluaci��n continua de los vectores direccionales m��s id��neos que el procedimiento generativo plantea���. La definici��n de complejidad en generaci��n y producci��n de formas en relaci��n con el proceso de dise��o digital param��trico global o integrado, es esencial para establecer un protocolo que optimice su gesti��n. ���Se propone como definici��n de complejidad como factor resultante de multiplicar el n��mero de agentes intervinientes por el n��mero de par��metros e interacciones comunes que intervienen en el proceso de generaci��n de la forma, dividido por la complejidad de intercambio de informaci��n digital desde el origen hasta la fase de fabricaci��n y construcci��n���. Una vez analizados los procesos de generaci��n digital de Arquitectura se propone identificar los par��metros geom��tricos que definen el proceso de Dise��o digital, entendiendose por Dise��o el proceso que engloba desde la proposici��n de una forma inicial basada en la intuici��n del Arquitecto, la generaci��n y evaluaci��n de variantes y posterior definici��n digital para producci��n, tanto de un objeto, un sistema o de la totalidad del Proyecto. En la actualidad el proceso de Dise��o es discontinuo y lineal organizandose los par��metros por disciplinas en las que est�� estructurada las atribuciones profesionales en la industria de la construcci��n. Para simplificar la identificaci��n y listado se han agrupado siguiendo estos grupos de conocimiento. Entendemos parametros invariables aquellos que son independientes de Tipolog��as arquitect��nicas o que dependen del mismo proceso de generaci��n de la Forma. ���El listado de los par��metros que intervienen en un proceso de generaci��n formal es una abstracci��n de una realidad compleja. La parametrizaci��n de las decisiones que intervienen en la selecci��n de una forma determinada mediante ���well defined problems��� es imposible. El proceso que esta tesis describe entiende esta condici��n como un elemento que pone en valor el propio procedimiento generativo por la riqueza que la subjetividad que el equipo de dise��o aporta���. La segunda parte esencial de esta investigaci��n pretende extraer las restricciones propias del estado del arte de la fabricaci��n digital para posteriormente incorporarlos en los procesos digitales de definici��n de la Forma arquitect��nica. ���La integraci��n de las restricciones derivadas de las t��cnicas de fabricaci��n y construcci��n digitales en el proceso de generaci��n de formas desde el ��mbito de la Arquitectura debe referirse a los condicionantes geom��tricos asociados a cada sistema constructivo, material y t��cnica de fabricaci��n. La geometr��a es adem��s el v��nculo que permite asociar el conjunto de par��metros prestacionales seleccionados para un Proyecto con los sistemas de fabricaci��n digital���. A estos condicionantes geom��tricos obtenidos del an��lisis de cada sistema de fabricaci��n digital se les ha denominado ���invariantes geom��tricos���. Bajo este t��rmino se engloban tanto l��mites dimensionales de fabricaci��n, como materiales compatibles, tolerancias de manufactura e instalaci��n y cualidades prestacionales asociadas. El objetivo de esta propuesta es emplear la geometr��a, herramienta fundamental y propia del Arquitecto, como nexo de uni��n entre el conjunto complejo y heterog��neo de par��metros previamente listados y analizados. Para ello se han simplificado en tablas espec��ficas para cada par��metro prestacional los condicionantes geom��tricos que se derivan de los Sistemas de fabricaci��n digital compatibles (ver ap��ndice 1). El estudio y evaluaci��n de las capacidades y objetivos de las distintas plataformas de software disponibles y de las experiencias profesionales evaluadas en los proyectos presentados, permiten concluir que la propuesta de plataforma digital de dise��o integral multi-param��trico de formas arquitect��nicas requiere de un protocolo de interoperatibilidad espec��fico a��n no universalmente establecido. Actualmente el enfoque de la estrategia para normalizar y universalizar el contexto normativo para regular la interoperatibilidad se centra en figura del gestor denominado ���BIM manager���. Las atribuciones y roles de esta figura se enfocan a la gesti��n del continente y no del contenido (Definici��n de los formatos de intercambio, niveles de desarrollo (LOD) de los componentes o conjuntos constructivos, detecci��n de interferencias y documentaci��n del propio modelo). Siendo este ��mbito un desarrollo necesario para la propuesta de universalizaci��n del sistema de dise��o para fabricaci��n digital integrado, la presente investigaci��n aporta un organigrama y protocolo asociado. El protocolo: 1. Establece la responsabilidad de identificar y definir la Informaci��n que debe determinar el proceso de generaci��n y desarrollo de la forma arquitect��nica. 2. Define la forma digital apropiada para generar la geometr��a del Proyecto, incluyendo la precisi��n necesaria para cada componente y el nivel de detalle necesario para su exportaci��n inequ��voca al proceso de fabricaci��n. 3. Define el tempo de cada etapa de dise��o identificando un nivel de detalle acorde. 4. Acopla este organigrama dentro de las estructuras nuevas que se proponen en un entorno BIM para asegurar que no se producen solapes o vac��os con las atribuciones que se identifican para el BIM Manager. ���El Arquitecto debe dirigir el protocolo de generaci��n coordinada con los sistemas de producci��n digital para conseguir que la integraci��n completa. El protocolo debe asistir al proceso de generaci��n de forma mediante la evaluaci��n del desempe��o prestacional de cada variante en tiempo real. La comunicaci��n entre herramientas digitales es esencial para permitir una ��gil transmisi��n de informaci��n. Es necesario establecer un protocolo adaptado a los objetivos y las necesidades operativas de cada proyecto ya que la estandarizaci��n de un protocolo ��nico no es posible���. Una decisi��n estrat��gica a la hora de planificar una plataforma de dise��o digital com��n es establecer si vamos a optar por un Modelo digital ��nico o diversos Modelos digitales federados. Cada uno de los modos de trabajo tiene fortalezas y debilidades, no obstante en el ��mbito de investigaci��n se ha concluido que un proceso integrado de Dise��o que incorpore la evaluaci��n prestacional y conceptual definida en el Cap��tulo 3, requiere necesariamente de varios modelos de software distintos que han de relacionarse entre s�� mediante un protocolo de comunicaci��n automatizado. Una plataforma basada en un modelo federado consiste en establecer un protocolo de comunicaci��n entre los programas inform��ticos empleados por cada disciplina. En este modelo de operaci��n cada equipo de dise��o debe establecer las bases de comunicaci��n en funci��n del n��mero y tipo de programas y procesos digitales a emplear. En esta investigaci��n se propone un protocolo basado en los est��ndares de intercambio de informaci��n que estructura cualquier proceso de generaci��n de forma param��trico ���La investigaci��n establece el empleo de algoritmos evolutivos como el sistema actual ��ptimo para desarrollar un proceso de generaci��n de formas basadas en la integraci��n y coordinaci��n de invariantes geom��tricos derivados de un conjunto de objetivos prestacionales y constructivos. No obstante, para la aplicaci��n en el caso pr��ctico realizado se ha podido verificar que la evaluaci��n del desempe��o a��n no puede realizarse en una ��nica herramienta y por lo tanto el proceso de selecci��n de las variantes gen��ticas ��ptimas ha de ejecutarse de forma manual y acumulativa. El proceso debe realizarse de manera federada para la selecci��n evolutiva de los invariantes geom��tricos dimensionales���. La evaluaci��n del protocolo de integraci��n y los condicionantes geom��tricos obtenidos como par��metros geom��tricos que controlan las posibles formas compatibles se realiza mediante su aplicaci��n en un caso pr��ctico. El ejercicio simula la colaboraci��n multidisciplinar con modelos federados de plataformas distintas. La elecci��n del tama��o y complejidad constructiva del proyecto se ha modulado para poder alcanzar un desarrollo completo de cada uno de los par��metros prestacionales seleccionados. Continuando con el mismo objetivo propuesto para los par��metros prestacionales, la tipolog��a constructiva-estructural seleccionada para el ejercicio permite la aplicaci��n la totalidad de invariantes geom��tricos asociados. El objetivo de este caso pr��ctico es evaluar la capacidad alterar la forma inicialmente propuesta mediante la evaluaci��n del desempe��o prestacional de conjunto de variantes geom��tricas generadas a partir de un par��metro dimensional determinado. Para que este proceso tenga sentido, cada una de las variantes debe ser previamente validada conforme a las limitaciones geom��tricas propias de cada sistema de fabricaci��n y montaje previstos. El inter��s de las conclusiones obtenidas es la identificaci��n de una variante geom��trica distante a la soluci��n sim��trica inicialmente como la soluci��n ��ptima para el conjunto de par��metros seleccionados. Al tiempo se ha comprobado como la participaci��n de un conjunto de par��metros multi-disciplinares que representan la realidad compleja de los objetivos arquitect��nicos favorecen la aparici��n de variaciones gen��ticas con prestaciones mejoradas a la intuici��n inicial. ���La herencias tipol��gicas suponen un l��mite para la imaginaci��n de variantes formales al proceso de ideaci��n arquitect��nica. El ejercicio realizado demuestra que incluso en casos donde aparentemente la soluci��n ��ptima aparenta ser obvia una variante aleatoria puede mejorar su desempe��o global. La posibilidad de conocer las condiciones geom��tricas de las t��cnicas de fabricaci��n digital compatibles con el conjunto de par��metros seleccionados por el Arquitecto para dirigir el proceso asegura que los resultados del algoritmo evolutivo empleado sean constructivamente viables. La mejora de imaginaci��n humana con la aportaci��n de geometr��as realmente construibles supone el objetivo ��ltimo de esta tesis���. ABSTRACT Architectural form generation process is shifting from analogical to digital. Digital technology has changed the way we design empowering Architects and Engineers to precisely define any complex geometry envisioned. At the same time, the construction industry, following aeronautical and automotive industries, is implementing digital manufacturing techniques to improve efficiency and quality. Consequently construction complexity will no longer be related to geometry complexity and it is associated to coordination with digital manufacturing capacities. Unfortunately it is agreed that non-standard geometries, even when proposed with performance optimization criteria, are only suitable for projects with non-restricted budgets. Furthemore, the lack of coordinated exportation protocol and geometry management between design and construction is avoiding the globalization of emergence process in built projects Present research first objective is to identify exclusive form-generation parameters related to digital manufacturing geometrical restraints. The intention was to use geometry as the form-generation tool and integrate the digital manufacturing capacities at first stages of the project. The first chapter of this text describes the investigation historical context focusing on the influence between accurate geometry definition at non-standard forms and its construction. At first examples of non-Euclidean geometries built the communication between design and construction were based on analogical partial and imprecise documentation. Deficient communication leads to geometry adaptation on site leaving the final form uncontrolled by the Architect. Computer Aided Design enable Architects to define univocally complex geometries that previously where impossible to communicate. ���The univocally definition of the Form, and communication between design and construction is essential for complex geometry Projects���. The second chapter is focused on digital technologies application in form finding process and site construction. The case studies selected identifies a clear inflexion node at 1992 with the Guggenheim Museum in Bilbao. The singularity of this project was the use of Aeronautics software to define digitally the external envelope complex geometry to enable the contractor to build it. ���The digital revolution has given the Architect the capacity to design buildings beyond the architectural archetypes driven by geometric-constructive limitations. The application of digital manufacturing techniques has enabled a free-form construction without geometrical limitations. In this new context performance shall be the responsible to set new conceptual boundaries, since the behavior of each possible geometry can be compare and analyze beforehand. The role of the Architect is to prioritize the performance and architectural objectives of each project in a complete and coherent set of parameters���. Projects using digital tools for solving various stages of the design process were increased exponentially since 1992 until today. Despite the significant rise of the techniques of computer-aided design the main challenge remains linking geometries and materials proposed at each design with the capabilities of digital manufacturing techniques. Design for manufacturing in a digital environment is a mature technology in other industries such as aerospace and automotive, including consumer products and decoration, but in the construction sector is an immature and disjointed system. The peculiarities of the construction industry have not yet been addressed in its entirety and research proposals made in this area until 2015 have focused in separate parts of the process and not the total process. ���The main obstacle to global standardization and implementation of a complete digital process from the form-finding to construction site is the lack of an integrated protocol that integrates manufacturing, economic and commissioning limitations, together with the performance evaluation of each possible form���. The different form generation processes are studied at chapter number 3. At the introduction of this chapter there is a specific definition of "form" for the research field. Form is identified with the outer envelope geometry, including the organizational set of connected indoor spaces connected to it. Therefore it is not exclusive of the interior. The aim of this study is to analyze and classify the main digital form generation processes using different selected projects as emblematic of each type. The approach to this process is complex, with segregated and uncoordinated different actors have to intervene application. In an analogical form-generation process parameters involved are partly conscious and partly unconscious or learned. The architect has control only over limited part of the parameters to be integrated into the design, according to their knowledge and. There is also a learned aesthetical prejudice that leads the form generation process to a specific geometry leaving the performance and optimization criteria apart from the decision making process. ���Using performance evaluation digital tools during form finding process provides real-time comparative information to the Architect enabling geometry selection based on its performance. The generative form generation process described at this document does not ambition to identify the optimum geometry for each set of parameters. The objective is to provide quick information at each generation of what direction is most favorable for the performance parameters selected���. Manufacturing complexity definition in relation to a global and integral process of digital design for manufacture is essential for establishing an efficient managing protocol. ���The definition of complexity associated to design for production in Architecture is proposed as the factor between number of different agents involved in the process by the number of interactions required between them, divided by the percentage of the interchange of information that is standardized and proof of information loss���. Design in architecture is a multi-objective process by definition. Therefore, addressing generation process linked to a set of non-coherent parameters requires the selection of adequate generative algorithm and the interaction of the architect. During the second half of the twentieth century and early twenty-first century it have been developed various mathematical algorithms for multi-parametric digital design. Heuristic algorithms are the most adequate algorithms for architectural projects due to its nature. The advantage of such algorithms is the ability to efficiently handle large scale optimization cases where a large number of design objectives and variables are involved. These generative processes do not pursue the optimum solution, in fact it will be impossible to proof with such algorithm. This is not a problem in architectural design where the final goal is to guide the form finding process towards a better performance within the initial direction provided by the architect. This research has focused on genetic algorithms due to its capacity to generate geometric alternatives in multiple directions and evaluate the fitness against a set of parameters specified in a single process. "Any protocol seeks to achieve standardization. The design to manufacturing protocol aims to provide a coordinated and coherent form generation process between a set of design parameters and the geometrical requirements of manufacturing technique. The protocol also provides an information exchange environment where there is a communication path and the level of information is ensured. The research is focused on the process because it is considered that each project will have its own singularities and parameters but the process will stay the same. Again the development of a specific tool is not a goal for the research, the intention is to provide an open source protocol that is valid for any set of tools���. Once the digital generation processes are being analized and classified, the next step is to identify the geometric parameters that define the digital design process. The definition of design process is including from the initial shape proposal based on the intuition of the architect to the generation, evaluation, selection and production of alternatives, both of an object , system or of the entire project . The current design process in Architecture is discontinuous and linear, dividing the process in disciplines in which the construction industry is structured. The proposal is to unify all relevant parameters in one process. The parameters are listed in groups of knowledge for internal classification but the matrix used for parameter relationship determination are combined. ���A multi-parameter determination of the form-finding process is the integration all the measurable decisions laying behind Architect intuition. It is not possible to formulate and solve with an algorithm the design in Architecture. It is not the intention to do so with the proposal of this research. The process aims to integrate in one open protocol a selection of parameters by using geometry as common language. There is no optimum solution for any step of the process, the outcome is an evaluation of performance of all the form variations to assist the Architect for the selection of the preferable solution for the project���. The research follows with the geometrical restrictions of today Digital manufacturing techniques. Once determined it has been integrated in the form-finding process. ���Digital manufacturing techniques are integrated in the form-finding process using geometry as common language. Geometric restraints define the boundary for performance parametric form-finding process. Geometrical limitations are classified by material and constructive system���. Choose between one digital model or several federate models is a strategic decision at planning a digital design for manufacturing protocol. Each one of the working models have strengths and weakens, nevertheless for the research purposes federated models are required to manage the different performance evaluation software platforms. A protocol based on federated models shall establish a communication process between software platforms and consultants. The manager shall integrate each discipline requirements defining the communication basis. The proposed protocol is based on standards on information exchange with singularities of the digital manufacturing industry. ���The research concludes evolutionary algorithms as current best system to develop a generative form finding process based on the integration and coordination of a set of performance and constructive objectives. However, for application in professional practice and standardize it, the performance evaluation cannot be done in only one tool and therefore the selection of optimal genetic variants must be run in several iterations with a cumulative result. Consequently, the evaluation process within the geometrical restraints shall be carried out with federated models coordinated following the information exchange protocol���. The integration protocol and geometric constraints evaluation is done by applying in a practical case study. The exercise simulates multidisciplinary collaboration across software platforms with federated models. The choice of size and construction complexity of the project has been modulated to achieve the full development of each of the parameters selected. Continuing with the same objective proposed for the performance parameters the constructive and structural type selected for the exercise allows the application all geometric invariants associated to the set of parameters selected. The main goal of the case study is to proof the capacity of the manufacturing integrated form finding process to generate geometric alternatives to initial form with performance improved and following the restrictions determined by the compatible digital manufacturing technologies. The process is to be divided in consecutive analysis each one limited by the geometrical conditions and integrated in a overall evaluation. The interest of this process is the result of a non-intuitive form that performs better than a double symmetrical form. The second conclusion is that one parameter evaluation alone will not justify the exploration of complex geometry variations, but when there is a set of parameters with multidisciplinary approach then the less obvious solution emerge as the better performing form. ���Architectural typologies impose limitation for Architects capacity to imagine formal variations. The case study and the research conclusions proof that even in situations where the intuitive solution apparently is the optimum solution, random variations can perform better when integrating all parameters evaluation. The capacity of foreseing the geometrical properties linking each design parameter with compatible manufacturing technologies ensure the result of the form-finding process to be constructively viable. Finally, the propose of a complete process where the geometry alternatives are generated beyond the Architect intuition and performance evaluated by a set of parameters previously selected and coordinated with the manufacturing requirements is the final objective of the Thesis���.

A Reliable Open-Source System Architecture for the Fast Designing and Prototyping of Autonomous Multi-UAV Systems: Simulation and Experimentation

During the process of design and development of an autonomous Multi-UAV System, two main problems appear. The first one is the difficulty of designing all the modules and behaviors of the aerial multi-robot system. The second one is the difficulty of having an autonomous prototype of the system for the developers that allows to test the performance of each module even in an early stage of the project. These two problems motivate this paper. A multipurpose system architecture for autonomous multi-UAV platforms is presented. This versatile system architecture can be used by the system designers as a template when developing their own systems. The proposed system architecture is general enough to be used in a wide range of applications, as demonstrated in the paper. This system architecture aims to be a reference for all designers. Additionally, to allow for the fast prototyping of autonomous multi-aerial systems, an Open Source framework based on the previously defined system architecture is introduced. It allows developers to have a flight proven multi-aerial system ready to use, so that they can test their algorithms even in an early stage of the project. The implementation of this framework, introduced in the paper with the name of ���CVG Quadrotor Swarm���, which has also the advantages of being modular and compatible with different aerial platforms, can be found at https://���github.���com/���Vision4UAV/���cvg_���quadrotor_���swarm with a consistent catalog of available modules. The good performance of this framework is demonstrated in the paper by choosing a basic instance of it and carrying out simulation and experimental tests whose results are summarized and discussed in this paper.

Milling quality and protein properties of autumn-sown Chinese wheats evaluated through multi-location trials

Eight milling quality and protein properties of autumn-sown Chinese wheats were investigated using 59 cultivars and advanced lines grown in 14 locations in China from 1995 to 1998. Wide ranges of variability for all traits were observed across genotypes and locations. Genotype, location, year, and their interactions all significantly influenced most of the quality parameters. Kernel hardness, Zeleny sedimentation value, and mixograph development time were predominantly influenced by the effects of genotype. Genotype, location and genotype x location interaction were all important sources of variation for thousand kernel weight, test weight, protein content, and falling number, whereas genotype x location interaction had the largest effect on flour yield. Most of the genotypes were characterized by weak gluten strength with Zeleny sedimentation values less than 40 ml and mixograph development time shorter than 3 min. Eight groups of genotypes were recognized based on the average quality performance, grain hardness and gluten strength were the two parameters that determined the grouping, with contributions from protein content. Genotypes such as Zhongyou 16 and Annong 8903 displayed good milling quality, high grain hardness, protein content and strong gluten strength with high sedimentation value and long mixograph development time. Genotypes such as Lumai 15 and Yumai 18 were characterized by low grain hardness, protein content and weak gluten strength. Genotypes such as Yannong 15 and Chuanmai 24 were characterized by strong gluten strength with high sedimentation value and long mixograph development time, but low grain hardness and protein content lower than 12.3%. Genotypes such as Jingdong 6 and Xi'an 8 had weak gluten strength, but with high grain hardness and protein content higher than 12.2%. Five groups of locations were identified, and protein content and gluten strength were the two parameters that determined the grouping. Beijing, Shijiazhuang, Nanyang, Zhumadian and Nanjing produced wheats with medium to strong gluten strength and medium protein content, although there was still a large variation for most of the traits investigated between the locations. Wheat produced in Yantai was characterized by strong gluten strength, but with low protein content. Jinan, Anyang and Linfen locations produced wheats with medium to weak gluten strength and medium to high protein content. Wheats produced in Yangling, Zhenzhou, and Chengdu were characterized by weak gluten strength with medium to low protein content, whereas wheats produced in Xuzhou and Wuhan were characterized by weak gluten strength with low protein content. Industrial grain quality could be substantially improved through integrating knowledge of geographic genotype distribution with key location variables that affected end-use quality.

Genetic algorithm based distance spectrum technique for performance union bound of space-time trellis coded OFDM

This paper derives the performance union bound of space-time trellis codes in orthogonal frequency division multiplexing system (STTC-OFDM) over quasi-static frequency selective fading channels based on the distance spectrum technique. The distance spectrum is the enumeration of the codeword difference measures and their multiplicities by exhausted searching through all the possible error event paths. Exhaustive search approach can be used for low memory order STTC with small frame size. However with moderate memory order STTC and moderate frame size the computational cost of exhaustive search increases exponentially, and may become impractical for high memory order STTCs. This requires advanced computational techniques such as Genetic Algorithms (GAS). In this paper, a GA with sharing function method is used to locate the multiple solutions of the distance spectrum for high memory order STTCs. Simulation evaluates the performance union bound and the complexity comparison of non-GA aided and GA aided distance spectrum techniques. It shows that the union bound give a close performance measure at high signal-to-noise ratio (SNR). It also shows that GA sharing function method based distance spectrum technique requires much less computational time as compared with exhaustive search approach but with satisfactory accuracy.

The dynamics of a genetic algorithm for a simple learning problem

A formalism for describing the dynamics of Genetic Algorithms (GAs) using method s from statistical mechanics is applied to the problem of generalization in a perceptron with binary weights. The dynamics are solved for the case where a new batch of training patterns is presented to each population member each generation, which considerably simplifies the calculation. The theory is shown to agree closely to simulations of a real GA averaged over many runs, accurately predicting the mean best solution found. For weak selection and large problem size the difference equations describing the dynamics can be expressed analytically and we find that the effects of noise due to the finite size of each training batch can be removed by increasing the population size appropriately. If this population resizing is used, one can deduce the most computationally efficient size of training batch each generation. For independent patterns this choice also gives the minimum total number of training patterns used. Although using independent patterns is a very inefficient use of training patterns in general, this work may also prove useful for determining the optimum batch size in the case where patterns are recycled.