Hardware/software codesign of configurable fuzzy control systems

Fuzzy inference techniques are an attractive and well-established approach for solving control problems. This is mainly due to their inherent ability to obtain robust, low-cost controllers from the intuitive (and usually ambiguous or incomplete) linguistic rules used by human operators when describing the control process. This paper focuses on the hardware/software codesign of configurable fuzzy control systems. Two prototype systems implemented on general-purpose development boards are presented. In both of them, hardware components are based on specific and configurable fuzzy inference architecture whereas software tasks are supported by a microcontroller. The first prototype uses an off-the-shelf microcontroller and a low-complexity Xilinx XC4005XL field programmable gate array (FPGA). The second one is implemented as a system on programmable chip (SoPC), integrating the microcontroller together with the fuzzy hardware architecture and its interface circuits into a Xilinx Spartan2E200 FPGA.Comisión Interministerial de Ciencia y Tecnología TIC2001-1726-C02-0

Annulation du QRS-T pour la détection de l'onde P : une approche par analyse een ondelettes dyadiques

Une nouvelle méthode d'annulation battement à battement du QRS-T dans le but de faciliter la détection de l'onde P est introduite. La phase d'annulation s'appuie sur une approche de pseudo inversion d'une décomposition en ondelettes dyadiques du signal ECG, observé sur deux dérivations, pour fournir un signal résiduel ne devant contenir que le train d'ondes P. Leur détection est par la suite entreprise sur ce signal et est abordée sous forme d'un problème de classification binaire. Des comparaisons, sur signaux simulés et réels, avec d'autres approches sont présentées

Sur les signaux électrophysiologiques : réflexion et quelques perspectives ouvertes

Nous disposons de signaux physiologiques riches en information sur les objets observés. Lorsque leur association est possible, ils peuvent renseigner différentes facettes du fonctionnement d'une entité structurelle, d'un organe ou encore d'un système. L'exploitation des informations qu'ils véhiculent en lien avec les données cliniques à des finalités diagnostiques et thérapeutique, mais aussi pour améliorer l'état des connaissances dans les champs disciplinaires concernés, demande de fédérer des équipes de recherche autour de projet intégrant d'emblée les dimensions méthodologiques, cliniques et technologiques

Codiseño hardware/software de un sistema de dosificación basado en lógica difusa

En esta comunicación se describe la realización mediante codiseño hardware/software de un sistema de dosificación que emplea técnicas de control basadas en lógica difusa. La implementación final se ha realizado sobre una placa de desarrollo que incluye una FPGA XC4005XL y un microcontrolador Intel 8031. Para el diseño del controlador difuso se ha utilizado un entorno de desarrollo de sistemas difusos de libre distribución, mientras que la síntesis hardware del sistema se ha llevado a cabo mediante versiones educativas de herramientas comerciales.Comisión Interministerial de Ciencia y Tecnología (CICYT) TIC98-086

Wavelet analysis of epileptic spikes

Interictal spikes and sharp waves in human EEG are characteristic signatures of epilepsy. These potentials originate as a result of synchronous, pathological discharge of many neurons. The reliable detection of such potentials has been the long standing problem in EEG analysis, especially after long-term monitoring became common in investigation of epileptic patients. The traditional definition of a spike is based on its amplitude, duration, sharpness, and emergence from its background. However, spike detection systems built solely around this definition are not reliable due to the presence of numerous transients and artifacts. We use wavelet transform to analyze the properties of EEG manifestations of epilepsy. We demonstrate that the behavior of wavelet transform of epileptic spikes across scales can constitute the foundation of a relatively simple yet effective detection algorithm.Comment: 4 pages, 3 figure

Predictors and outcome impact of perioperative serum sodium changes in a high-risk population.

BACKGROUND: The perioperative period may be associated with a marked neurohumoral stress response, significant fluid losses, and varied fluid replacement regimes. Acute changes in serum sodium concentration are therefore common, but predictors and outcomes of these changes have not been investigated in a large surgical population. METHODS: We carried out a retrospective cohort analysis of 27 068 in-patient non-cardiac surgical procedures in a tertiary teaching hospital setting. Data on preoperative conditions, perioperative events, hospital length of stay, and mortality were collected, along with preoperative and postoperative serum sodium measurements up to 7 days after surgery. Logistic regression was used to investigate the association between sodium changes and mortality, and to identify clinical characteristics associated with a deviation from baseline sodium >5 mmol litre(-1). RESULTS: Changes in sodium concentration >5 mmol litre(-1) were associated with increased mortality risk (adjusted odds ratio 1.49 for a decrease, 3.02 for an increase). Factors independently associated with a perioperative decrease in serum sodium concentration >5 mmol litre(-1) included age >60, diabetes mellitus, and the use of patient-controlled opioid analgesia. Factors associated with a similar increase were preoperative oxygen dependency, mechanical ventilation, central nervous system depression, non-elective surgery, and major operative haemorrhage. CONCLUSIONS: Maximum deviation from preoperative serum sodium value is associated with increased hospital mortality in patients undergoing in-patient non-cardiac surgery. Specific preoperative and perioperative factors are associated with significant serum sodium changes.This work was supported by the Cambridge University Division of Anaesthesia.This is the author accepted manuscript. The final version is available from Oxford University Press via http://dx.doi.org/10.1093/bja/aeu40

Effect of Addition of PET in the Thermal Properties of Polymer-Mortar Composite Materials

The polymer-mortar composites are often used as low-cost promising materials for preventing or repairing various reinforced concrete structures. The Thermal behavior of the ¶building materials ¶is relevant to any use of concrete or composite, especially in relation to structures where it is desirable to have low thermal conductivity, dimensional stability, high specific heat and little or no decrease of stiffness upon heating. Although much work has been done on the effect of admixture and the mechanical properties of concrete or composite, relatively little work has been done on the thermal conductivity. So, Thermal conductivity (l), thermal resistance (R) and the surface coefficients of transmission (U) of polymer-mortar composites made up of mixtures of polyethylene terephthalate PET waste were measured. To determine the effect of the PET on the thermal conductivity of PET-mortar composites, PET was added as replacement for cement by decreasing the cement weights in the ratios of 2.5%, 5% and 7.5% by weight. The highest thermal conductivity of 1.45 W/mK was observed with the samples containing only plain cement. It decreased with the increase of PET as replacement for cement. The lowest value of thermal conductivity and the surface coefficient of transmission were obtained with the samples prepared with PET waste polymer at 7.5 % replacement of cement. The composites were also observed by DTA, MOP led to the positive identification of the products’. In this way, the results obtained highlight the beneficial effect of waste PET as thermal insulation in comparison with other insulation materials. In addition, the obtained PET-mortar composites would appear to be low-cost materials which would contribute to resolving some of the solid waste problems in addition to conserving energy

The puzzle of self-reported weight gain in a month of fasting (Ramadan) among a cohort of Saudi families in Jeddah, Western Saudi Arabia

<p>Abstract</p> <p>Background</p> <p>During Ramadan fast, approximately one billion Muslims abstain from food and fluid between the hours of sunrise to sunset, and usually eat a large meal after sunset and another meal before sunrise. Many studies reported good health-related outcomes of fasting including weight loss. The objective of this study is to identify the local pattern of expenditure on food consumption, dietary habits during Ramadan and correlate that to self-reported weight gain after Ramadan in a group of families in Jeddah, Western Saudi Arabia.</p> <p>Methods</p> <p>A Cross-section study using a pre-designed questionnaire to identify the local pattern of expenditure on food consumption, dietary habits during Ramadan and correlate that to self-reported weight gain after Ramadan in a representative cohort of Saudis living in Jeddah. It was piloted on 173 nutrition students and administered by them to their families.</p> <p>Results</p> <p>A total of 173 Saudi families were interviewed. One out of 5 indicated that their expenditure increases during Ramadan. Approximately two thirds of the respondents (59.5%) reported weight gain after Ramadan. When asked about their perspective explanations for that: 40% attributed that to types of foods being rich in fat and carbohydrates particularly date in (Sunset meal) 97.7% and rice in (Dawn meal) 80.9%. One third (31.2%) indicated that it was due to relative lack of physical exercise in Ramadan and 14.5% referred that to increase in food consumption. Two thirds (65.2%) of those with increased expenditure reported weight gain.</p> <p>Conclusion</p> <p>Surprisingly weight gain and not weight loss was reported after Ramadan by Saudis which indicates timely needed life-style and dietary modification programs for a population which reports one of the highest prevalence rates of diabetes.</p