Deep Learning Implementation of Model Predictive Control for Multi-Output Resonant Converters

Flexible-surface induction cooktops rely on multi-coil structures which are powered by means of advanced resonant power converters that achieve high versatility while maintaining high efficiency and power density. The study of multi-output converters has led to cost-effective and reliable implementations even if they present complex control challenges to provide high performance. For this scenario, model predictive control arises as a modern control technique that is capable of handling multivariable problems while dealing with nonlinearities and constraints. However, these controllers are based on the computationally-demanding solution of an optimization problem, which is a challenge for high-frequency real-time implementations. In this context, deep learning presents a potent solution to approximate the optimal control policy while achieving a time-efficient evaluation, which permits an online implementation. This paper proposes and evaluates a multi-output-resonant-inverter model predictive controller and its implementation on an embedded system by means of a deep neural network. The proposal is experimentally validated by a resonant converter applied to domestic induction heating featuring a two-coil 3.6 kW architecture controlled by means of a FPGA. Autho

Mains-Synchronized Pulse Density Modulation Strategy Applied to a ZVS Resonant Matrix Inverter

Multi-output inverters have become a key enabling technology to increase surface flexibility in domestic induction heating appliances. The most commonly used power converter topologies are based on electromechanical relays in order to multiplex the connected loads and obtain a proper heat distribution. This solution, which is used in combination with other modulations such as square waveform, relies on the thermal inertia of the pot as it needs long power-averaging periods to reduce the reiteration of the switching noise. However, it presents a significant limitation in terms of acoustic noise, reliability, and thermal performance. To overcome these limitations, complete solid-state inverters that can be operated at higher frequencies are proposed. This change in the design paradigm of the pulse density modulation strategies leads to improved thermal control in the pot and better user experience, but at the same time increases challenges due to design constraints imposed by electromagnetic compatibility regulations. This article analyzes the possibilities of a new mains-synchronized pulse density modulation applied to a flexible induction cooktop that uses a multiple-output ZVS resonant inverter topology. The feasibility of the control strategies has been tested by means of a prototype featuring 12 2-kW induction heating loads. © 1982-2012 IEEE

Variabilidad entre el ángulo de Clarke y el índice de Chippaux- Smirak para el diagnóstico de pie plano

[Abstract] Background: The measurements used in diagnosing biomechanical pathologies vary greatly. The aim of this study was to determine the concordance between Clarke's angle and Chippaux-Smirak index, and to determine the validity of Clarke's angle using the Chippaux-Smirak index as a reference. Methods: Observational study in a random population sample (n= 1,002) in A Coruña (Spain). After informed patient consent and ethical review approval, a study was conducted of anthropometric variables, Charlson comorbidity score, and podiatric examination (Clarke's angle and Chippaux-Smirak index). Descriptive analysis and multivariate logistic regression were performed. Results: The prevalence of flat feet, using a podoscope, was 19.0% for the left foot and 18.9% for the right foot, increasing with age. The prevalence of flat feet according to the Chippaux-Smirak index or Clarke's angle increases significantly, reaching 62.0% and 29.7% respectively. The concordance (kappa I) between the indices according to age groups varied between 0.25-0.33 (left foot) and 0.21-0.30 (right foot). The intraclass correlation coefficient (ICC) between the Chippaux-Smirak index and Clarke's angle was -0.445 (left foot) and -0.424 (right foot). After adjusting for age, body mass index (BMI), comorbidity score and gender, the only variable with an independent effect to predict discordance was the BMI (OR= 0.969; 95% CI: 0.940-0.998). Conclusion: There is little concordance between the indices studied for the purpose of diagnosing foot arch pathologies. In turn, Clarke's angle has a limited sensitivity in diagnosing flat feet, using the Chippaux-Smirak index as a reference. This discordance decreases with higher BMI values.[Resumen] Introducción: Existe una gran variabilidad en las mediciones para el diagnóstico de la patología biomecánica. El objetivo de este estudio fue determinar la concordancia entre el ángulo de Clarke y el índice de Chippaux-Smirak, para determinar la validez del ángulo de Clarke utilizando como referencia el índice de Chippaux-Smirak. Métodos: Se realizó un estudio observacional en una muestra aleatoriamente seleccionada (n= 1,002) en A Coruña (España). Tras el consentimiento informado del paciente y la aprobación del comité de ética, se estudiaron variables, antropométricas, índice de comorbilidad de Charlson y un examen podológico (ángulo de Clarke, índice de Chippaux-Smirak). Se realizó un estudio descriptivo y un análisis multivariado de regresión logística. Resultados: La prevalencia de pie plano utilizando el podoscopio fue de 19.0%(pie izquierdo) y 18.9%(pie derecho), incrementándose con la edad. La prevalencia de pie plano según el índice ChippauxSmirak o el ángulo de Clarke se incrementan considerablemente llegando a 62.0% y 29.7%. La concordancia (kappa I) entre los índices según grupos de edad oscila entre 0.25-0.33 (pie izquierdo) y 0.210.30 (pie derecho). El coeficiente de correlación intraclase (CCI) entre el índice de Chippaux-Smirak y el ángulo de Clarke es -0.445 (pie izquierdo) y 0.424 (pie derecho). Tras ajustar por edad, índice de masa corporal (IMC), score de comorbilidad y sexo la única variable con un efecto independiente para predecir discordancia es el IMC (OR= 0.969; IC 95%: 0.94-0.998). Conclusiones: La concordancia entre los índices estudiados para el diagnóstico de la patología del arco plantar es reducida. Existe a su vez una reducida sensibilidad del ángulo de Clarke para el diagnóstico de pie plano, utilizando como referencia el índice de Chippaux-Smirak. Esta discordancia disminuye con valores más altos de IMC

Seminario de demandas de agua en El Salvador

Uno de los problemas mas importantes para el diseñador de abastecimiento de agua es la consideración que es necesario hacer con respecto a los valores de los consumos promedio diario a la población a la cual se le quiere suministrar agua potable. Los factores que inciden para la estimación de estos valores son: el nivel económico de la población servida, calidad del agua, continuidad en el servicio de agua, estado de la red de distribución, presión de servicio adecuad0.estos factores son variados que la posibilidad de obtener datos verdaderamente exactos lleva a suposiciones que no hace mas que conducir a diseños antieconómico

Analysing the concept of diagnostic inertia in hypertension: a cross-sectional study

Aims The aim of this study was to quantify diagnostic inertia (DI) when the physician fails to diagnose hypertension and determine its associated factors. Methods This cross-sectional, observational study involved all patients without a diagnosis of hypertension who had their blood pressure (BP) measured at least three times during the second half of 2010 (N = 48,605). Patients with altered mean BP figures (≥ 140/90 mmHg) were considered to experience DI. Secondary variables: gender, atrial fibrillation, diabetes mellitus, dyslipidemia, cardiovascular disease, age and the physician having attended a cardiovascular training course (ESCARVAL). Associated factors were assessed by multivariate logistic regression analysis. Results Diagnostic inertia was present in 6450 patients (13.3%, 95% CI: 13.0–13.6%). Factors significantly associated with DI were: male gender (OR = 1.46, 95% CI: 1.37–1.55, p < 0.001), atrial fibrillation (OR = 0.73, 95% CI: 0.58–0.92, p = 0.007), the ESCARVAL cardiovascular course (OR = 0.88, 95% CI: 0.81–0.96, p = 0.005), diabetes mellitus (OR = 0.93, 95% CI: 0.87–0.99, p = 0.016), cardiovascular disease (OR = 0.77, 95% CI: 0.67–0.88, p < 0.001) and older age (years) (18–44[RIGHTWARDS ARROW]OR = 1; 45–59[RIGHTWARDS ARROW]OR = 12.45, 95% CI: 11.11–13.94; 60–74[RIGHTWARDS ARROW]OR = 18.11, 95% CI: 16.30–20.12; ≥ 75[RIGHTWARDS ARROW]OR = 20.43, 95% CI: 18.34–22.75; p < 0.001). The multivariate model had an area under the ROC curve of 0.81 (95% CI: 0.80–0.81, p < 0.001). Conclusions This study will help clinical researchers differentiate between the two forms of DI (interpretation of a positive screening test and interpretation of positive diagnostic criteria). The results found here in patients with hypertension suggest that this problem is prevalent, and that a set of associated factors can explain the outcome well (AUC>0.80)

Medication Non-Adherence in Rheumatology, Oncology and Cardiology: A Review of the Literature of Risk Factors and Potential Interventions

Medication adherence is directly associated with health outcomes. Adherence has been reviewed extensively; however, most studies provide a narrow scope of the problem, covering a specific disease or treatment. This project’s objective was to identify risk factors for non-adherence in the fields of rheumatology, oncology, and cardiology as well as potential interventions to improve adherence and their association with the risk factors. The project was developed in three phases and carried out by a Steering Committee made up of experts from the fields of rheumatology, oncology, cardiology, general medicine, and hospital and community pharmacy. In phase 1, a bibliographic review was performed, and the articles/reviews were classified according to the authors’ level of confidence in the results and their clinical relevance. In phase 2, 20 risk factors for non-adherence were identified from these articles/reviews and agreed upon in Steering Committee meetings. In phase 3, potential interventions for improving adherence were also identified and agreed upon. The results obtained show that adherence is a dynamic concept that can change throughout the course of the disease, the treatments, and other factors. Educational interventions are the most studied ones and have the highest level of confidence in the authors’ opinion. Information and education are essential to improve adherence in all patients

Cardiovascular preventive recommendations. PAPPS 2020 update

The recommendations of the semFYC's Program for Preventive Activities and Health Promotion (PAPPS) for the prevention of cardiovascular diseases (CVD) are presented. The following sections are included: Epidemiological review, where the current morbidity and mortality of CVD in Spain and its evolution as well as the main risk factors are described; Cardiovascular (CV) risk tables and recommendations for the calculation of CV risk; Main risk factors such as arterial hypertension, dyslipidemia and diabetes mellitus, describing the method for their diagnosis, therapeutic objectives and recommendations for lifestyle measures and pharmacological treatment; Indications for antiplatelet therapy, and recommendations for screening of atrial fibrillation. The quality of testing and the strength of the recommendation are included in the main recommendations.Se presentan las recomendaciones del Programa de Actividades Preventivas y Promoción de la Salud (PAPPS) de la semFYC, para la prevención de las enfermedades cardiovasculares (CV). Se incluyen los siguientes apartados: Revisión epidemiológica, donde se describe la morbimortalidadCV actual en España y su evolución y los principales factores de riesgo; Tablas de riesgo CV y recomendaciones para el cálculo del riesgo CV; Factores de riesgo mayores como hipertensión arterial, dislipidemia y diabetes mellitus, describiendo el método para su diagnóstico, los objetivos terapéuticos y las recomendaciones de medidas d estilo de vida y de tratamiento farmacológico; Indicaciones de antiagregación, y Recomendaciones para el cribado de la fibrilación auricular. Para las principales recomendaciones se incluyen tablas específicas que recogen la calidad de la evidencia y la fuerza de la recomendación

Placebo-controlled trial of nimodipine in the treatment of acute ischemic cerebral infarction

Nimodipine is a 1,4-dihydropyridine derivative that shows a preferential cerebrovascular activity in experimental animals. Clinical data suggest that nimodipine has a beneficial effect on the neurologic outcome of patients suffering an acute ischemic stroke. Our double-blind placebo-controlled multicenter trial was designed to assess the effects of oral nimodipine on the mortality rate and neurologic outcome of patients with an acute ischemic stroke. One hundred sixty-four patients were randomly allocated to receive either nimodipine tablets (30 mg q.i.d.) or identical placebo tablets for 28 days. Treatment was always started less than or equal to 48 hours after the acute event. The Mathew Scale, slightly modified by Gelmers et al, was used for neurologic assessment. Mortality rate and neurologic outcome after 28 days were used as evaluation criteria. We considered 123 patients to be valid for the analysis of efficacy. Mortality rates did not differ significantly between groups. Neurologic outcome after 28 days of therapy did not differ between groups. However, when only those patients most likely to benefit from any intervention (Mathew Scale sum score of less than or equal to 65 at baseline) were analyzed separately in post hoc-defined subgroups, the nimodipine-treated subgroups showed a significantly better neurologic outcome. This result suggests that some patients with acute ischemic stroke will benefit from treatment with nimodipine tablets

Characterizing diagnostic inertia in arterial hypertension with a gender perspective in primary care

Background and Objectives: Substantial evidence shows that diagnostic inertia leads to failure to achieve screening and diagnosis objectives for arterial hypertension (AHT). In addition, different studies suggest that the results may differ between men and women. This study aimed to evaluate the differences in diagnostic inertia in women and men attending public primary care centers, to identify potential gender biases in the clinical management of AHT. Study Design/Materials and methods: Cross-sectional descriptive and analytical estimates were obtained nested on an epidemiological ambispective cohort study of patients aged ≥30 years who attended public primary care centers in a Spanish region in the period 2008-2012, belonging to the ESCARVAL-RISK cohort. We applied a consistent operational definition of diagnostic inertia to a registry- reflected population group of 44,221 patients with diagnosed hypertension or meeting the criteria for diagnosis (51.2% women), with a mean age of 63.4 years (62.4 years in men and 64.4 years in women). Results: Of the total population, 95.5% had a diagnosis of hypertension registered in their electronic health record. Another 1,968 patients met the inclusion criteria for diagnostic inertia of hypertension, representing 4.5% of the total population (5% of men and 3.9% of women). The factors significantly associated with inertia were younger age, normal body mass index, elevated total cholesterol, coexistence of diabetes and dyslipidemia, and treatment with oral antidiabetic drugs. Lower inertia was associated with age over 50 years, higher body mass index, normal total cholesterol, no diabetes or dyslipidemia, and treatment with lipid-lowering, antiplatelet, and anticoagulant drugs. The only gender difference in the association of factors with diagnostic inertia was found in waist circumference. Conclusion: In the ESCARVAL-RISK study population presenting registered AHT or meeting the functional dia

Non-compliance of dyslipaemic patients with electronic prescriptions

Estudio observacional, descriptivo y transversal con un componente analítico en una oficina de farmacia comunitaria sita en Huércal-Overa que tiene el objetivo de determinar el grado de adherencia en pacientes en tratamiento hipolipidemiante y prescripción por receta electrónica