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The use of automated insulin delivery systems has become a reality for people with type 1 diabetes (T1D), with several hybrid systems already on the market. One of the particularities of this technology is that the patient is in the loop. People with T1D are the plant to control and also a plant operator, because they may have to provide information to the control loop. The most immediate information provided by patients that affects performance and safety are the announcement of meals and exercise. Therefore, to ensure safety and performance, the human factor impact needs to be addressed by designing fault monitoring strategies. In this paper, a monitoring system is developed to diagnose potential patient modes and faults. The monitoring system is based on the residual generation of a bank of observers. To that aim, a linear parameter varying (LPV) polytopic representation of the system is adopted and a bank of Kalman filters is designed using linear matrix inequalities (LMI). The system uncertainty is propagated using a zonotopic-set representation, which allows determining confidence bounds for each of the observer outputs and residuals. For the detection of modes, a hybrid automaton model is generated and diagnosis is performed by interpreting the events and transitions within the automaton. The developed system is tested in simulation, showing the potential benefits of using the proposed approach for artificial pancreas systems., Peer Reviewed, Postprint (published version)

This is a copy of an article published in the Diabetes Technology and Therapeutics © 2012 [copyright Mary Ann Liebert, Inc.]; Diabetes Technology and Therapeutics is available online at: http://online.liebertpub.com., [EN] Objective: Prandial insulin dosing is an empirical practice associated frequently with poor reproducibility in postprandial glucose response. Based on continuous glucose monitoring (CGM), a method for prandial insulin administration (iBolus) is presented and evaluated for people with type 1 diabetes using CSII therapy. Subjects and Methods: An individual patient¿s model for a 5-h postprandial period was obtained from 6-day ambulatory CGM and used for iBolus calculation in 12 patients with type 1 diabetes. In a double-blind, crossover study each patient underwent four meal tests with 40 g or 100 g of carbohydrates (CHOs), both on two occasions. For each meal, the iBolus or the traditional bolus (tBolus) was given before mealtime (t 0) in a randomized order. We measured the postprandial glycemic response as the area under the curve of plasma glucose (AUC-PG0¿5h) and variability as the individual coef¿cient of variation (CV) of AUC-PG0¿5h. The contribution of the insulin-to-CHO ratio, CHO, plasma glucose at t 0 (PGt0), and insulin dose to AUC-PG0¿5h and its CV was also investigated. Results: AUC-PG0¿5h was similar with either bolus for 40-g (iBolus vs. tBolus, 585.5¿127.5 vs. 689.2¿180.7 mg/dL$h) or 100-g (752.1¿237.7 vs. 760.0¿263.2 mg/dL$h) CHO meals. A multiple regression analysis revealed a signi¿cant model only for the tBolus, with PGt0 being the best predictor of AUC-PG0¿5h explaining approximately 50% of the glycemic response. Observed variability was greater with the iBolus (CV, 16.7¿15.3% vs. 10.1¿12.5%) but independent of the factors studied. Conclusions: A CGM-based algorithm for calculation of prandial insulin is feasible, although it does not reduce unpredictability of individual glycemic responses. Causes of variability need to be identi¿ed and analyzed for further optimization of postprandial glycemic control.

Copyright 2009 Proceedings of SPIE, the International Society for Optical Engineering. One print or electronic copy may be made for personal use only. Systematic electronic or print reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited., This paper explores the use of Principal Component Analysis (PCA), an extended form of PCA and, the T2- statistic and Q-statistic; distances that detect and distinguish damages in structures under varying operational and environmental conditions. The work involves an experiment in which two piezoelectric transducers are bonded on an aluminium plate. The plate is subjected to several damages and exposed to different levels of temperature. A series of tests have been performed for each condition. The approach is able to determine whether the structure has damage or not, and besides, gives qualitative information about its size, isolating effects of the temperature., Peer Reviewed, Postprint (author's final draft)

A hybrid reasoning system is developed for damage assessment of structures. The system combines the use of a model of the structure with a knowledge-based reasoning scheme to evaluate if damage is present, its severity (severity and dimension) and its location. Using a given model (or several models), the structural dynamic responses to given excitations are simulated in the presence of different forms of damage. In a ‘learning mode’ an initial casebase is created with the principal features of these damage responses. When the system is working in its operating mode, data acquired by sensors are used to perform a diagnosis by analogy with the cases stored in the casebase, reusing and adapting old situations. Whenever a new situation is detected, it is retained in the casebase to update the available information. This paper describes the methodology and how the system is built and tuned to be ready for operation. This is illustrated by a numerical example of a cantilever truss structure and tested numerically and experimentally with a beam structure. Conclusions are presented with the emphasis on the advantages of using knowledge-based systems for structural assessment., Peer Reviewed, Postprint (published version)

El autor nos explica la aparición de las primeras emisoras de radio católicas y, más adelante, la desaparición de las pequeñas emisoras parroquiales y la integración de las mayores en la Cadena de Ondas Populares Españolas (COPE). Sin embargo, en Cataluña, se produce un distanciamiento entre la jerarquía eclesiástica y la COPE, que llega a su máximo grado en 1993. En 1994 nace Ràdio Estel, una emisora que combina radiofórmula y programas hablados en la línea de las emisoras católicas y ecuménicas existentes en Francia e Italia.