On the Uncertainty Identification for Linear Dynamic Systems Using Stochastic Embedding Approach with Gaussian Mixture Models

In control and monitoring of manufacturing processes, it is key to understand model uncertainty in order to achieve the required levels of consistency, quality, and economy, among others. In aerospace applications, models need to be very precise and able to describe the entire dynamics of an aircraft. In addition, the complexity of modern real systems has turned deterministic models impractical, since they cannot adequately represent the behavior of disturbances in sensors and actuators, and tool and machine wear, to name a few. Thus, it is necessary to deal with model uncertainties in the dynamics of the plant by incorporating a stochastic behavior. These uncertainties could also affect the effectiveness of fault diagnosis methodologies used to increment the safety and reliability in real-world systems. Determining suitable dynamic system models of real processes is essential to obtain effective process control strategies and accurate fault detection and diagnosis methodologies that deliver good performance. In this paper, a maximum likelihood estimation algorithm for the uncertainty modeling in linear dynamic systems is developed utilizing a stochastic embedding approach. In this approach, system uncertainties are accounted for as a stochastic error term in a transfer function. In this paper, we model the error-model probability density function as a finite Gaussian mixture model. For the estimation of the nominal model and the probability density function of the parameters of the error-model, we develop an iterative algorithm based on the Expectation-Maximization algorithm using the data from independent experiments. The benefits of our proposal are illustrated via numerical simulations

A data augmentation approach for a class of statistical inference problems.

We present an algorithm for a class of statistical inference problems. The main idea is to reformulate the inference problem as an optimization procedure, based on the generation of surrogate (auxiliary) functions. This approach is motivated by the MM algorithm, combined with the systematic and iterative structure of the Expectation-Maximization algorithm. The resulting algorithm can deal with hidden variables in Maximum Likelihood and Maximum a Posteriori estimation problems, Instrumental Variables, Regularized Optimization and Constrained Optimization problems. The advantage of the proposed algorithm is to provide a systematic procedure to build surrogate functions for a class of problems where hidden variables are usually involved. Numerical examples show the benefits of the proposed approach

Prótesis bioclimáticas: interfaz emancipadora para la libre adaptabilidad de los espacios transicionales

People can influence and participate in the creation of technologies based on their own adaptability and self-construction behaviours in contexts of vulnerable housing. Currently, one of the main challenges of design is to reflect on its ability to be an agent in social transformation, in this case, from the generation of components and artefacts to adapt transitional spaces in domestic architecture. The weak thermal comfort and lack of adaptability that characterize social housing in Latin America makes urgent to seek solutions to rehabilitate and improve existing housing. The interventions on the transitional spaces, which are located in a hybrid environment, between the interior and the exterior, blurring limits between public and private spaces, creating complexity, have a double value. On one hand, they are decisive to reduce energy demands; and on the other hand, they allow the generation of their own intermediate spaces to foster social interaction. Recognizing these dual values, we propose to develop a system of adaptable technological solutions to be build and installed progressively by the people themselves, which are called Bioclimatic Prostheses, for houses and facades as a prosthesis to a body, with the aim of supplying special necessities, recognizing climate, environment and the community's own knowledge.Las personas pueden influenciar y participar en la creación de tecnologías a partir de sus propios comportamientos de adaptabilidad y autoconstrucción en contextos de vulnerabilidad habitacional. Actualmente, uno de los desafíos del diseño, es reflexionar sobre su capacidad para ser agente en la transformación social, en este caso, desde la generación de artefactos para adaptar espacios transicionales en la arquitectura. El débil confort térmico y la baja adaptabilidad que caracteriza a las viviendas sociales de América Latina hace urgente buscar soluciones para rehabilitar y mejorar viviendas existentes. La intervención sobre los espacios transicionales, que se ubican en un ámbito híbrido entre el interior y el exterior, entre lo público y lo privado, poseen un valor doble. Por un lado, son determinantes para las demandas de confort y energía; por otro lado, permiten generar espacios intermedios propios para la interacción. Reconociendo estos valores duales, se propone el diseño de un sistema guiado de soluciones tecnológicas flexibles, adaptables y auto construibles por las propias personas, que se denominan Prótesis bioclimáticas, integrables a la casa como una prótesis a un cuerpo, con el objetivo de suplir una necesidad espacial, reconociendo la naturaleza material y los conocimientos propios de la comunidad

Caleta modelo Isla Alejando Selkrik, archipiélago de Juan Fernández: Intervención arquitectónica desde la protección del medio natural y la identidad cultural.

Índice• Introducción • Metodología• Área de estudio • El escenario inicial • Resultados• Medidas de diseño sustentable • Planificación del uso del terreno según las característica geográficas climáticas y el trabajo del pescador • Aplicación del concepto de eficiencia energética • Uso de las energías renovables • Manejo de aguas de lluvia y erosión • Manejo de desechos • Consideraciones de diseño urbano • Discusión y conclusiones • Referencias bibliográficas Resumen Se presenta una propuesta de diseño arquitectónico en la isla Alejandro Selkirk, archipiélago de Juan Fernández, Chile, la cual se inscribe como parte de un proyecto interdisciplinario actualmente en desarrollo. El diseño recoge las necesidades de un grupo organizado de pescadores que requieren localizar y asentar sus actividades en una caleta modelo que considere los atributos naturales del entorno, la eficiencia energética, mejore sus tareas productivas y a su vez las relaciones de identidad cultural que caracterizan a los territorios insulares. Esta caleta modelo se propone como un asentamiento sustentable tipo para áreas extremas del país, de mínimo impacto y que incluye prototipos arquitectónicos destinados a cumplir con diferentes objetivos urbanos tanto de habitabilidad como de equipamientos de uso público y comunitario. Abstract We present an architectural designer in Alexander Selkirk Island, Juan Fernandez archipelago, Chile, which entered as part of an interdisciplinary project currently under development. The design reflects the needs of an organized group of fishermen who need to locate and establish their activities in a cache model that considers the natural attributes of the environment, energy efficiency, improve their productive activities and in turn the cultural identity relations that characterize island territories. This inlet model is proposed as a sustainable settlement for such extreme areas of the country, including low impact and architectural prototypes designed to meet different objectives of both urban livability as public facilities and community

Caleta modelo Isla Alejando Selkrik, archipiélago de Juan Fernández: Intervención arquitectónica desde la protección del medio natural y la identidad cultural.

ÍndiceIntroducciónMetodologíaÁrea de estudioEl escenario inicialResultadosMedidas de diseño sustentablePlanificación del uso del terreno según las característica geográficas climáticas y el trabajo del pescadorAplicación del concepto de eficiencia energéticaUso de las energías renovablesManejo de aguas de lluvia y erosiónManejo de desechosConsideraciones de diseño urbanoDiscusión y conclusionesReferencias bibliográficas ResumenSe presenta una propuesta de diseño arquitectónico en la isla Alejandro Selkirk, archipiélago de Juan Fernández, Chile, la cual se inscribe como parte de un proyecto interdisciplinario actualmente en desarrollo. El diseño recoge las necesidades de un grupo organizado de pescadores que requieren localizar y asentar sus actividades en una caleta modelo que considere los atributos naturales del entorno, la eficiencia energética, mejore sus tareas productivas y a su vez las relaciones de identidad cultural que caracterizan a los territorios insulares. Esta caleta modelo se propone como un asentamiento sustentable tipo para áreas extremas del país, de mínimo impacto y que incluye prototipos arquitectónicos destinados a cumplir con diferentes objetivos urbanos tanto de habitabilidad como de equipamientos de uso público y comunitario.AbstractWe present an architectural designer in Alexander Selkirk Island, Juan Fernandez archipelago, Chile, which entered as part of an interdisciplinary project currently under development. The design reflects the needs of an organized group of fishermen who need to locate and establish their activities in a cache model that considers the natural attributes of the environment, energy efficiency, improve their productive activities and in turn the cultural identity relations that characterize island territories. This inlet model is proposed as a sustainable settlement for such extreme areas of the country, including low impact and architectural prototypes designed to meet different objectives of both urban livability as public facilities and community

Caleta modelo Isla Alejando Selkrik, archipiélago de Juan Fernández: Intervención arquitectónica desde la protección del medio natural y la identidad cultural

Índice• Introducción • Metodología• Área de estudio • El escenario inicial • Resultados• Medidas de diseño sustentable • Planificación del uso del terreno según las característica geográficas climáticas y el trabajo del pescador • Aplicación del concepto de eficiencia energética • Uso de las energías renovables • Manejo de aguas de lluvia y erosión • Manejo de desechos • Consideraciones de diseño urbano • Discusión y conclusiones • Referencias bibliográficas Resumen Se presenta una propuesta de diseño arquitectónico en la isla Alejandro Selkirk, archipiélago de Juan Fernández, Chile, la cual se inscribe como parte de un proyecto interdisciplinario actualmente en desarrollo. El diseño recoge las necesidades de un grupo organizado de pescadores que requieren localizar y asentar sus actividades en una caleta modelo que considere los atributos naturales del entorno, la eficiencia energética, mejore sus tareas productivas y a su vez las relaciones de identidad cultural que caracterizan a los territorios insulares. Esta caleta modelo se propone como un asentamiento sustentable tipo para áreas extremas del país, de mínimo impacto y que incluye prototipos arquitectónicos destinados a cumplir con diferentes objetivos urbanos tanto de habitabilidad como de equipamientos de uso público y comunitario. Abstract We present an architectural designer in Alexander Selkirk Island, Juan Fernandez archipelago, Chile, which entered as part of an interdisciplinary project currently under development. The design reflects the needs of an organized group of fishermen who need to locate and establish their activities in a cache model that considers the natural attributes of the environment, energy efficiency, improve their productive activities and in turn the cultural identity relations that characterize island territories. This inlet model is proposed as a sustainable settlement for such extreme areas of the country, including low impact and architectural prototypes designed to meet different objectives of both urban livability as public facilities and community

Contemporary use of cefazolin for MSSA infective endocarditis: analysis of a national prospective cohort

Objectives: This study aimed to assess the real use of cefazolin for methicillin-susceptible Staphylococcus aureus (MSSA) infective endocarditis (IE) in the Spanish National Endocarditis Database (GAMES) and to compare it with antistaphylococcal penicillin (ASP). Methods: Prospective cohort study with retrospective analysis of a cohort of MSSA IE treated with cloxacillin and/or cefazolin. Outcomes assessed were relapse; intra-hospital, overall, and endocarditis-related mortality; and adverse events. Risk of renal toxicity with each treatment was evaluated separately. Results: We included 631 IE episodes caused by MSSA treated with cloxacillin and/or cefazolin. Antibiotic treatment was cloxacillin, cefazolin, or both in 537 (85%), 57 (9%), and 37 (6%) episodes, respectively. Patients treated with cefazolin had significantly higher rates of comorbidities (median Charlson Index 7, P <0.01) and previous renal failure (57.9%, P <0.01). Patients treated with cloxacillin presented higher rates of septic shock (25%, P = 0.033) and new-onset or worsening renal failure (47.3%, P = 0.024) with significantly higher rates of in-hospital mortality (38.5%, P = 0.017). One-year IE-related mortality and rate of relapses were similar between treatment groups. None of the treatments were identified as risk or protective factors. Conclusion: Our results suggest that cefazolin is a valuable option for the treatment of MSSA IE, without differences in 1-year mortality or relapses compared with cloxacillin, and might be considered equally effective