945 resultados para New multiaxial fatigue criteria


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An important objective of the INTEGRATE project1 is to build tools that support the efficient execution of post-genomic multi-centric clinical trials in breast cancer, which includes the automatic assessment of the eligibility of patients for available trials. The population suited to be enrolled in a trial is described by a set of free-text eligibility criteria that are both syntactically and semantically complex. At the same time, the assessment of the eligibility of a patient for a trial requires the (machineprocessable) understanding of the semantics of the eligibility criteria in order to further evaluate if the patient data available for example in the hospital EHR satisfies these criteria. This paper presents an analysis of the semantics of the clinical trial eligibility criteria based on relevant medical ontologies in the clinical research domain: SNOMED-CT, LOINC, MedDRA. We detect subsets of these widely-adopted ontologies that characterize the semantics of the eligibility criteria of trials in various clinical domains and compare these sets. Next, we evaluate the occurrence frequency of the concepts in the concrete case of breast cancer (which is our first application domain) in order to provide meaningful priorities for the task of binding/mapping these ontology concepts to the actual patient data. We further assess the effort required to extend our approach to new domains in terms of additional semantic mappings that need to be developed.

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Many studies have been developed to analyze the structural seismic behavior through the damage index concept. The evaluation of this index has been employed to quantify the safety of new and existing structures and, also, to establish a framework for seismic retrofitting decision making of structures. Most proposed models are based in a posterthquake evaluation in such a way they uncouple the structural response from the damage evaluation. In this paper, a generalization of the model by Flórez-López (1995) is proposed. The formulation employs irreversible thermodynamics and internal state variable theory applied to the study of beams and frames and it allows and explicit coupling between the degradation and the structural mechanical behavior. A damage index es defined in order to model elastoplasticity coupled with damage and fatigue damage.

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There has been much discussion on the primacy of theory over practice. Today prevails the exaggeration of practice. This idea forgets too that teaching problem is a problem of right balance. The approach of the action lines on the European Higher Education Area (EHEA) framework provides for such balance. Applied Geology subject represents the first real contact with the physical environment with the practice profession and works. Besides, the situation of the topic in the first trace of Study Plans for many students implies the link to other subjects and topics of the career. This work analyses in depth the justification of such practical trips only on Applied Geology. This methodology could be usual in Study Plans of pure sciences career, Geology or Biology, but not in Civil Engineering like teaching method. It shows the criteria and methods of planning and the result which manifests itself in pupils. Therefore, work shows a methodology taking in account the engineering perspective, the practical point of view and the learning process inside students and their evaluation and, hence, their marks.

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In this paper we present a global overview of the recent study carried out in Spain for the new hazard map, which final goal is the revision of the Building Code in our country (NCSE-02). The study was carried our for a working group joining experts from The Instituto Geografico Nacional (IGN) and the Technical University of Madrid (UPM) , being the different phases of the work supervised by an expert Committee integrated by national experts from public institutions involved in subject of seismic hazard. The PSHA method (Probabilistic Seismic Hazard Assessment) has been followed, quantifying the epistemic uncertainties through a logic tree and the aleatory ones linked to variability of parameters by means of probability density functions and Monte Carlo simulations. In a first phase, the inputs have been prepared, which essentially are: 1) a project catalogue update and homogenization at Mw 2) proposal of zoning models and source characterization 3) calibration of Ground Motion Prediction Equations (GMPE’s) with actual data and development of a local model with data collected in Spain for Mw < 5.5. In a second phase, a sensitivity analysis of the different input options on hazard results has been carried out in order to have criteria for defining the branches of the logic tree and their weights. Finally, the hazard estimation was done with the logic tree shown in figure 1, including nodes for quantifying uncertainties corresponding to: 1) method for estimation of hazard (zoning and zoneless); 2) zoning models, 3) GMPE combinations used and 4) regression method for estimation of source parameters. In addition, the aleatory uncertainties corresponding to the magnitude of the events, recurrence parameters and maximum magnitude for each zone have been also considered including probability density functions and Monte Carlo simulations The main conclusions of the study are presented here, together with the obtained results in terms of PGA and other spectral accelerations SA (T) for return periods of 475, 975 and 2475 years. The map of the coefficient of variation (COV) are also represented to give an idea of the zones where the dispersion among results are the highest and the zones where the results are robust.

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La ecología no solamente ha puesto de manifiesto problemas ambientales, sino que ha confirmado la necesidad de una nueva armonía entre los propios seres humanos y de éstos con la naturaleza y con todos los seres que la habitan. Es necesario un nuevo contrato que determine nuestras relaciones con la Naturaleza (Serrs1), y una nueva Ética para nuestras vidas (Guattari2). La ética medioambiental nos ha dado una visión universal y supra-generacional de la gestión de la naturaleza y como consecuencia, una nueva forma de construir nuestra ‘segunda’ Naturaleza, que es la arquitectura. ¿Qué es lo esencial que esta nueva ética exige para la arquitectura? Este es un momento crucial para reconsiderar los objetivos de la arquitectura, porque lo ‘eco’ está produciendo grandes cambios. ¿Implica esta era post-ecológica una particular ética, es decir, referida a sus fines y medios? ¿Porqué, para qué, para quién, cómo debemos hacer la arquitectura de nuestro tiempo? Es momento de afrontar críticamente el discurso de la eco-arquitectura, e incluso de repensar los propios límites de la arquitectura. El desarrollo actual del conocimiento medioambiental es esencialmente técnico y utilitario, pero ¿es el reto solamente técnico?¿Es suficiente la suma de lo medioambiental-social-económico-cultural para definirla? ¿Hay claves que nos puedan dar la dimensión ética de esta aproximación técnica-empírica? ¿Sabemos lo que estamos haciendo cuando aplicamos este conocimiento? Y, sobre todo, ¿cuál es el sentido de lo que estamos haciendo? La tesis que se propone puede resumirse: De acuerdo con el actual conocimiento que tenemos de la Naturaleza, la Arquitectura de nuestro tiempo deber reconsiderar sus fines y medios, puesto que la ética medioambiental está definiendo nuevos objetivos. Para fundamentar y profundizar en esta afirmación la tesis analiza cómo son hoy día las relaciones entre Ética-Naturaleza-Arquitectura (Fig.1), lo que facilitará las claves de cuáles son los criterios éticos (en cuanto a fines y medios) que deben definir la arquitectura del tiempo de la ecología. ABSTRACT Ecology shows us not only environmental problems; it shows that we need a new balance and harmony between individuals, beings, communities and Nature. We need a new contract with Nature according to Serres576, and a new Ethics for our lives according to Guattari577. Environmental ethics have given us a universal and supra-generational vision of the management of our Nature and, as a consequence, a new way to construct our ‘second’ nature, which is architecture. What is essential for this new architecture that the new ethics demand? This is a critical moment to reconsider the object of architecture, because the ‘eco’ is making significant changes in it. Are there any specifically ethical concerns (ends and means) in the post-ecological era? Why, for what, for whom, how should we make architecture in our times? This is the time to approach the eco-architectural discourse critically and to question the current boundaries of architecture itself: Where is eco-architecture going? The current development of environmental knowledge is essentially technical and utilitarian, but it is its technical aspect the only challenge? Is the sum of environmental-social-economic aspects enough to define it? Are there any clues which can give an ethical sense to this technical-empirical approach? Do we know what we are doing when we apply this knowledge? And overall, what is the meaning of what we are doing? Exploring this subject, this thesis makes a statement: In accordance with the actual knowledge of Nature, Architecture of our time must reconsider its ends and means, since the environmental ethics is defining new objectives. To support that, the thesis analyzes what the relationships between Ethics –Nature- Architecture (Fig. 53) are like nowadays, this will provide the clues of which ethical criteria (ends and means) must architecture of an ecological era define.

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The carbonation of concrete or the chlorides ingress in such quantity to reach the level of bars is triggers of reinforcement corrosion. One of the most significant effects of reinforcing steel corrosion on reinforced concrete structures is the decline in the ductility-related properties of the steel. Reinforcement ductility has a decisive effect on the overall ductility of reinforced concrete structures. Different Codes classify the type of steel depending on their ductility defined by the minimum values of several parameters. Using indicators of ductility associating different properties can be advantageous on many occasions. It is considered necessary to define the ductility by means of a single parameter that considers strength values and deformation simultaneously. There are a number of criteria for defining steel ductility by a single parameter. The present experimental study addresses the variation in the ductility of concrete-embedded steel bars when exposed to accelerated corrosion. This paper analyzes the suitability of a new indicator of ductility used in corroded bars.

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The building sector is well known to be one of the key energy consumers worldwide. The renovation of existing buildings provides excellent opportunities for an effective reduction of energy consumption and greenhouse gas emissions but it is essential to identify the optimal strategies. In this paper a multi-criteria methodology is proposed for the comparative analysis of retrofitting solutions. Life Cycle Assessment (LCA) and Life Cycle Cost (LCC) are combined by expressing environmental impacts in monetary values. A Pareto optimization is used to select the preferred strategies. The methodology is exemplified by a case study: the renovation of a representative housing block from the 1960s located in Madrid. Eight scenarios have been proposed, from the Business as Usual scenario (BAU), through Spanish Building Regulation requirements (for new buildings) up to the Passive House standard. Results show how current renovation strategies that are being applied in Madrid are far from being optimal solutions. The required additional investment, which is needed to obtain an overall performance improvement of the envelope compared with the common practice to date, is relatively low (8%) considering the obtained life cycle environmental and financial savings (43% and 45%, respectively).

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La medida de calidad de vídeo sigue siendo necesaria para definir los criterios que caracterizan una señal que cumpla los requisitos de visionado impuestos por el usuario. Las nuevas tecnologías, como el vídeo 3D estereoscópico o formatos más allá de la alta definición, imponen nuevos criterios que deben ser analizadas para obtener la mayor satisfacción posible del usuario. Entre los problemas detectados durante el desarrollo de esta tesis doctoral se han determinado fenómenos que afectan a distintas fases de la cadena de producción audiovisual y tipo de contenido variado. En primer lugar, el proceso de generación de contenidos debe encontrarse controlado mediante parámetros que eviten que se produzca el disconfort visual y, consecuentemente, fatiga visual, especialmente en lo relativo a contenidos de 3D estereoscópico, tanto de animación como de acción real. Por otro lado, la medida de calidad relativa a la fase de compresión de vídeo emplea métricas que en ocasiones no se encuentran adaptadas a la percepción del usuario. El empleo de modelos psicovisuales y diagramas de atención visual permitirían ponderar las áreas de la imagen de manera que se preste mayor importancia a los píxeles que el usuario enfocará con mayor probabilidad. Estos dos bloques se relacionan a través de la definición del término saliencia. Saliencia es la capacidad del sistema visual para caracterizar una imagen visualizada ponderando las áreas que más atractivas resultan al ojo humano. La saliencia en generación de contenidos estereoscópicos se refiere principalmente a la profundidad simulada mediante la ilusión óptica, medida en términos de distancia del objeto virtual al ojo humano. Sin embargo, en vídeo bidimensional, la saliencia no se basa en la profundidad, sino en otros elementos adicionales, como el movimiento, el nivel de detalle, la posición de los píxeles o la aparición de caras, que serán los factores básicos que compondrán el modelo de atención visual desarrollado. Con el objetivo de detectar las características de una secuencia de vídeo estereoscópico que, con mayor probabilidad, pueden generar disconfort visual, se consultó la extensa literatura relativa a este tema y se realizaron unas pruebas subjetivas preliminares con usuarios. De esta forma, se llegó a la conclusión de que se producía disconfort en los casos en que se producía un cambio abrupto en la distribución de profundidades simuladas de la imagen, aparte de otras degradaciones como la denominada “violación de ventana”. A través de nuevas pruebas subjetivas centradas en analizar estos efectos con diferentes distribuciones de profundidades, se trataron de concretar los parámetros que definían esta imagen. Los resultados de las pruebas demuestran que los cambios abruptos en imágenes se producen en entornos con movimientos y disparidades negativas elevadas que producen interferencias en los procesos de acomodación y vergencia del ojo humano, así como una necesidad en el aumento de los tiempos de enfoque del cristalino. En la mejora de las métricas de calidad a través de modelos que se adaptan al sistema visual humano, se realizaron también pruebas subjetivas que ayudaron a determinar la importancia de cada uno de los factores a la hora de enmascarar una determinada degradación. Los resultados demuestran una ligera mejora en los resultados obtenidos al aplicar máscaras de ponderación y atención visual, los cuales aproximan los parámetros de calidad objetiva a la respuesta del ojo humano. ABSTRACT Video quality assessment is still a necessary tool for defining the criteria to characterize a signal with the viewing requirements imposed by the final user. New technologies, such as 3D stereoscopic video and formats of HD and beyond HD oblige to develop new analysis of video features for obtaining the highest user’s satisfaction. Among the problems detected during the process of this doctoral thesis, it has been determined that some phenomena affect to different phases in the audiovisual production chain, apart from the type of content. On first instance, the generation of contents process should be enough controlled through parameters that avoid the occurrence of visual discomfort in observer’s eye, and consequently, visual fatigue. It is especially necessary controlling sequences of stereoscopic 3D, with both animation and live-action contents. On the other hand, video quality assessment, related to compression processes, should be improved because some objective metrics are adapted to user’s perception. The use of psychovisual models and visual attention diagrams allow the weighting of image regions of interest, giving more importance to the areas which the user will focus most probably. These two work fields are related together through the definition of the term saliency. Saliency is the capacity of human visual system for characterizing an image, highlighting the areas which result more attractive to the human eye. Saliency in generation of 3DTV contents refers mainly to the simulated depth of the optic illusion, i.e. the distance from the virtual object to the human eye. On the other hand, saliency is not based on virtual depth, but on other features, such as motion, level of detail, position of pixels in the frame or face detection, which are the basic features that are part of the developed visual attention model, as demonstrated with tests. Extensive literature involving visual comfort assessment was looked up, and the development of new preliminary subjective assessment with users was performed, in order to detect the features that increase the probability of discomfort to occur. With this methodology, the conclusions drawn confirmed that one common source of visual discomfort was when an abrupt change of disparity happened in video transitions, apart from other degradations, such as window violation. New quality assessment was performed to quantify the distribution of disparities over different sequences. The results confirmed that abrupt changes in negative parallax environment produce accommodation-vergence mismatches derived from the increasing time for human crystalline to focus the virtual objects. On the other side, for developing metrics that adapt to human visual system, additional subjective tests were developed to determine the importance of each factor, which masks a concrete distortion. Results demonstrated slight improvement after applying visual attention to objective metrics. This process of weighing pixels approximates the quality results to human eye’s response.

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This work presents the evaluation of a new non-contact technique to assess the fatigue damage state of CFRP structures by measuring surface roughness parameters. Surface roughness and stiffness degradation have been measured in CFRP coupons cycled with constant amplitude loads, and a Pearson?s correlation of 0.79 was obtained between both variables. Results suggest that changes on the surface roughness measured in strategic zones of components made of the evaluated CFRP, could be indicative of the level of damage due to fatigue loads. This methodology could be useful for other FRP due to similarities in the fatigue damage process.

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The EPA promulgated the Exceptional Events Rule codifying guidance regarding exclusion of monitoring data from compliance decisions due to uncontrollable natural or exceptional events. This capstone examines documentation systems utilized by agencies requesting data be excluded from compliance decisions due to exceptional events. A screening tool is developed to determine whether an event would meet exceptional event criteria. New data sources are available to enhance analysis but evaluation shows many are unusable in their current form. The EPA and States must collaborate to develop consistent evaluation methodologies documenting exceptional events to improve the efficiency and effectiveness of the new rule. To utilize newer sophisticated data, consistent, user-friendly translation systems must be developed.

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The Growing Neural Gas model is used widely in artificial neural networks. However, its application is limited in some contexts by the proliferation of nodes in dense areas of the input space. In this study, we introduce some modifications to address this problem by imposing three restrictions on the insertion of new nodes. Each restriction aims to maintain the homogeneous values of selected criteria. One criterion is related to the square error of classification and an alternative approach is proposed for avoiding additional computational costs. Three parameters are added that allow the regulation of the restriction criteria. The resulting algorithm allows models to be obtained that suit specific needs by specifying meaningful parameters.

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Aims. In this study we conduct a pilot program aimed at the red supergiant population of the Magellanic Clouds. We intend to extend the current known sample to the unexplored low end of the brightness distribution of these stars, building a more representative dataset with which to extrapolate their behaviour to other Galactic and extra-galactic environments. Methods. We select candidates using only near infrared photometry, and with medium resolution multi-object spectroscopy, we perform spectral classification and derive their line-of-sight velocities, confirming the nature of the candidates and their membership in the clouds. Results. Around two hundred new red supergiants have been detected, hinting at a yet to be observed large population. Using near- and mid-infrared photometry we study the brightness distribution of these stars, the onset of mass-loss, and the effect of dust in their atmospheres. Based on this sample, new a priori classification criteria are investigated, combining mid- and near-infrared photometry to improve the observational efficiency of similar programs to this.

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The subject of Construction of Structures I studies, from a constructive point of view and taking into account current legislation, reinforced concrete structures used in buildings, through the acquisition of knowledge and construction criteria required in the profession of a Technical Architect. The contents acquired in this course are essential for further professional development of technicians and are closely related to many of the subjects taught in the same or other courses of the Degree in Technical Architecture at the University of Alicante. The aim of this paper is to present, analyze and discuss the development of a new methodology proposed in the mentioned subject, as it supposed an important change in the traditional way of teaching Construction and Structures I. In order to incorporate new teaching tools in 2013-2014, the course has been implemented by using a Moodle software tool to promote blended learning with online exercises. Our Moodle community allows collaborative work within an open-source platform where teachers and students share a new and personalized learning environment. Students are easily used to the interface and the platform, value the constant connection with teachers or other fellows and completely agree with the possibility of making questions or share documents 24 hours a day. The proposed methodology consists of lectures and practical classes. In the lectures, the basics of each topic are discussed; class attendance, daily study and conducting scheduled exercises are indispensable. Practical classes allow to consolidate the knowledge gained in theory classes by solving professional exercises and actual construction problems related to structures, that shall be compulsorily delivered online. So, after the correction of the teacher and the subsequent feedback of students, practical exercises ensure lifelong learning of the student, who can download any kind of material at any time (constructive details, practical exercises and even corrected exams). Regarding the general evaluation system, goals achievement is assessed on an ongoing basis (65% of the final mark) along the course through written and graphic evidences in person and online, as well as a individual development of a workbook. In all cases, the acquisition of skills, the ability to synthesize, the capacity of logical and critical thinking are assessed. The other 35 % of the mark is evaluated by a complementary graphic exam. Participation in the computing platform is essential and the student is required to do and present, at least 90% of the practices proposed. Those who do not comply with the practices in each specific date could not be assessed continuously and may only choose the final exam. In conclusion, the subject of Construction of Structures I is essential in the development of the regulated profession of Technical Architect as they are considered, among other professional profiles, as specialists in construction of building structures. The use of a new communication platform and online teaching allows the acquisition of knowledge and constructive approaches in a continuous way, with a more direct and personal monitoring by the teacher that has been highly appreciated by almost 100% of the students. Ultimately, it is important to say that the use of Moodle in this subject is a very interesting tool, which was really well welcome by students in one of the densest and important subjects of the Degree of Technical Architecture.

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Federal financial structures which include fiscal equalization between the states are and will remain to be indispensable. Such structures are required to equalize the significant regional economic differences which exist within the federal republic and to ensure sufficient funding for the responsibilities of the public sector across the nation. The current federal financial structures have a number of structural flaws which regard both the criteria for tax distribution, the design of the debt brake and the role of municipalities. The financial structures will have to be revised beginning in 2020. The objective is to consolidate in the long term the budgets of federation, state and municipal governments and to safe-guard a modern welfare state.

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BACKGROUND Eosinophilic esophagitis (EoE) is a rapidly emerging, chronic inflammatory, genetically impacted disease of the esophagus, defined clinically by symptoms of esophageal dysfunction and, pathologically, by an eosinophil-predominant tissue infiltration. However, in four EoE-families, we have identified patients presenting with EoE-typical and corticosteroid-responsive symptoms, but without tissue eosinophilia. It was the aim of this study to clinically and immunologically characterize these patients with EoE-like disease. METHODS Five patients suffering from an EoE-like disease were evaluated with endoscopic, histologic, functional and quantitative immunohistologic examinations, and mRNA expression determination. RESULTS The frequency of first generation offspring of EoE-like disease patients affected by EoE or EoE-like disease was 40%. Immunofluorescence analysis confirmed an almost complete absence of eosinophils in the esophageal tissues of patients with EoE-like disease, but revealed a considerable T cell infiltration, comparable to EoE. In contrast to EoE, eotaxin-3 mRNA and protein were markedly reduced in EoE-like disease (P < 0.05). The mRNA expression levels of three selected EoE genes (eotaxin-3, MUC4 and CDH26) allowed to discriminate between EoE-like disease, EoE and normal epithelium. CONCLUSIONS Patients suffering from "EoE without eosinophilia" do not fulfill formally the diagnostic criteria for EoE. However, their clinical manifestation, immunohistology and gene-expression pattern, plus the fact that they bequeath EoE to their offspring, suggest a uniform underlying pathogenesis. Conventional EoE, with its prominent eosinophilia, therefore appears to be only one phenotype of a broader "inflammatory dysphagia syndrome" spectrum. In this light, the role of the eosinophils, the definition of EoE, and its diagnostic criteria must likely be reconsidered. This article is protected by copyright. All rights reserved.