Low-Cost Oil Quality Sensor Based on Changes in Complex Permittivity

Real time oil quality monitoring techniques help to protect important industry assets, minimize downtime and reduce maintenance costs. The measurement of a lubricant’s complex permittivity is an effective indicator of the oil degradation process and it can be useful in condition based maintenance (CBM) to select the most adequate oil replacement maintenance schedules. A discussion of the working principles of an oil quality sensor based on a marginal oscillator to monitor the losses of the dielectric at high frequencies (>1 MHz) is presented. An electronic design procedure is covered which results in a low cost, effective and ruggedized sensor implementation suitable for use in harsh environments

Una concepción moderna de Técnicas de Inteligencia Artificial en la Universidad de Alicante

Este trabajo tiene como objetivo presentar la estructura de la asignatura Técnicas de Inteligencia Artificial en la Universidad de Alicante haciendo especial hincapié en los recursos (nuevas tecnologías, material docente y aplicaciones software) empleados durante el desarrollo de la misma. Parte de estos recursos docentes están siendo empleados como herramienta de apoyo para la adaptación al Espacio Europeo de Educación Superior

Let’s Play Democracy, Exploratory Analysis of Political Video Games

In current times, the concept of democracy has been transformed due to the ups and downs of the hyperdigitalized society, modifying its discourses and forms of participation. Recognizing that video games maintain a prominent role in the new generations, this research has the objective of analyzing independent video games related to the notion of democracy. For this reason, 26 video games were analyzed according to their democratic principles, their typology and their key components, resulting in a tendency towards the guarantee of civil liberties, political pluralism and separation of powers; likewise, there is a clear differentiation between persuasive and expressive video games, the former linked to polarization and criticism, while the latter responded to a reflexive conceptual line, added to the use of reward systems and progression in their key design components. It can be concluded that video games linked to democracy respond to an innovative interactive dimension that converts the traditional political canons by the creativity, freedom, and autonomy of the current audiences.Partial funding for open access charge: Universidad de Málag

Validación del Münchner Alkoholismus Test Subjektiv para el diagnóstico de alcoholismo en población adulta

ResumenObjetivoValidar la parte subjetiva del cuestionario MALT (Münchner Alkoholismus Test) para el diagnóstico de alcoholismo en población adulta.DiseñoEstudio descriptivo de validación de un instrumento diagnóstico.EmplazamientoDos centros de atención primaria, un centro de drogodependencias y un centro de atención a alcohólicos, ubicados en la provincia de Córdoba, España.ParticipantesSeiscientos catorce pacientes con edades de entre 18 y 80 años.Mediciones principalesMediante entrevista personal se realizaron los cuestionarios MALT, AUDIT (Alcohol Use Disorders Identification Test) y el SCAN (Schedules for clinical assessment in Neuropsychiatry). Se analizó la fiabilidad interna, la reproducibilidad, la validez criterial (patrón de referencia: criterios del Manual Diagnóstico y Estadístico de los Trastornos Mentales IV [DSM-IV]) y la validez convergente.ResultadosLa edad media de la población fue de 43 años (desviación estándar de 1,43). El 17,4% presentó síndrome de dependencia alcohólica. Los coeficientes kappa de los ítems del test oscilaban entre 0,568 y 0,969. El alfa de Cronbach del MALT completo fue de 0,919; el alfa de Cronbach del MALT subjetivo fue de 0,939, y el alfa de Cronbach del MALT objetivo fue de 0,737. El área bajo la curva de eficacia diagnóstica para el MALT-S fue de 0,946 y para el MALT completo fue de 0,953. Para un punto de corte de 4, la sensibilidad del MALT-S fue del 92,6% y la especificidad fue del 90,8%. El coeficiente de correlación del MALT-S y del AUDIT fue de 0,86 (p<0,001).ConclusionesEl MALT subjetivo es un cuestionario tan válido y fiable como el MALT completo, por lo que puede ser utilizado aisladamente para la detección y el diagnóstico de alcoholismo.AbstractObjectiveTo validate the subjective part of the MALT questionnaire (MALT-S) for the detection of alcoholism among the adult population.DesignA descriptive study on the validation of a diagnostic tool.SettingTwo primary health care centres, a centre for drug addicts and a centre for alcoholics in Cordoba (Spain).Participants614 patients, between 18 and 80 years.MeasurementsThrough personal interviews the MALT, AUDIT and SCAN questionnaires were given. The internal reliability, stability and both the criterion and convergent validity were analysed.ResultsThe mean age of the population’ was 43±1.43 (SD) years and 17.4% of them showed Alcohol Dependence Syndrome. The Kappa coefficients of the test items ranged from 0.568 to 0.969. The Cronbach alpha of the complete MALT was 0.919, of the MALT-S, 0.939 and of the MALT-O, 0.737. The area under the ROC curve of the MALT-S was 0.946 and that of the complete MALT was 0.953. For a cut-off point of four, the sensitivity of the MALT-S is 92.7% while its specificity was 90.9%. The correlation coefficient of the MALT-S and AUDIT was 0.86 (P<0.001).ConclusionsThe MALT-S questionnaire is as valid and reliable as the complete MALT; therefore, it can be used on its own for the diagnosis of alcoholism

Damage Detection in Metallic Beams from Dynamic Strain Measurements under Different Load Cases by Using Automatic Clustering and Pattern Recognition Techniques

International audienceIn general, the change in the local strain field or global stiffness caused by damage in a structure is very small and the strain field tends to homogenize very quickly in the field close to the defect. Moreover, other environmental effects can fade the slight changes in the strain field. Only by comparing the response of the structure at several points some information about damage may be unveiled. By means of pattern recognition techniques based on the strain field, this task can be achieved. This is the basis of the strain measurements data-driven models. The main limitation of the strain field pattern recognition techniques lies in the susceptibility of the strain field to change depending on the load conditions. In the case of dynamic loads, this may reflect even a greater limitation. Robust automated techniques are required to manage these limitations. In first instance, automatic clustering techniques are needed so that data can be classified according to the load conditions and secondly, a dimensional reduction technique is needed in order to obtain patterns that often underlie from data. Within the context of this paper, a combination of Local Density-based Simultaneous Two-Level (DS2L-SOM) Clustering based on Self-Organizing Maps (SOM) and Principal Components Analysis (PCA) is proposed in order to firstly, classify load conditions and secondly, perform strain field pattern recognition. The clustering technique is the basis for an Optimal Baseline Selection. An experimental validation of the technique is discussed in this paper, comparing damages of different sizes and positions in an aluminum beam, under a set of combined loads under dynamic conditions. Strains were measured at several points by using Fiber Bragg Gratings

Energy efficient active vibration control strategies using electromagnetic linear actuators

Energy efficient current control methods in electromagnetic linear actuators are required to minimize the electrical power requirements imposed by active vibration control strategies. In this paper an efficient bidirectional buck-boost converter is discussed in two scenarios: an active vibration isolation system and an active dynamic vibration absorber (ADVA) using a voice coil motor (VCM) actuator. An electrical analogous circuit of an experimental test platform is used as part of the simulation model. This test platform is based on a vibration shaker that provides the based excitation required for the single Degree of-Freedom (1DoF) vibration model under study. The proposed bidirectional non-isolated buck-boost converter can recover the energy when the VCM acts as a generator and store it for future use. Simulation results prove that this type of topology is far more efficient than linear amplifiers typically used in active vibration control. Within the context of slender structures, this efficient current control method improves the viability of using active vibration control in flexible structures such as beams

Use of Porous Titanium Trabecular as a Bone Defect Regenerator: In Vivo Study

The application of porous materials is increasingly being used in orthopaedic surgery due to its good results. Bone growth within the pores results in excellent mechanical fixation with the bone, as well as good bone regeneration. The pores, in addition to being colonised by bone, produce a decrease in the modulus of elasticity that favours the transfer of loads to the bone. This research shows the results of an experimental study where we have created critical osteoperiosteal defects of 10 mm on rabbit’s radius diaphysis. In one group of 10 rabbits (experimental group) we have implanted a bioactive porous titanium cylinder, and in another group we have allowed spontaneous regeneration (control group). Mechanical tests were performed to assess the material. Image diagnostic techniques (X-ray, scanner and 3D scan: there are no references on the literature with the use of CT-scan in bone defects) and histological and histomorphometric studies post-op and after 3, 6 and 12 months after the surgery were performed. All the control cases went through a pseudoarthrosis. In 9 of the 10 cases of the experimental group complete regeneration was observed, with a normal cortical-marrow structure established at 6 months, similar to normal bone. Titanium trabecular reached a bone percentage of bone inside the implant of 49.3% on its surface 3 months post-op, 75.6% at 6 months and 81.3% at 12 months. This porous titanium biomaterial has appropriate characteristics to allow bone ingrowth, and it can be proposed as a bone graft substitute to regenerate bone defects, as a scaffold, or as a coating to achieve implant osteointegration

A Pattern Recognition Approach for Damage Detection and Temperature Compensation in Acousto-Ultrasonics

International audienceThe global trends in the construction of modern structures require the integration of sensors together with data recording and analysis modules so that their integrity can be continuously monitored for safe-life, economic and ecological reasons. This process of measuring and analysing the data from a distributed sensor network all over a structural system in order to quantify its condition is known as structural health monitoring (SHM). Guided ultrasonic wave-based techniques are increasingly being adapted and used in several SHM systems which benefit from built&#8208,in transduction, large inspection ranges, and high sensitivity to small flaws. However, for reliable health monitoring, much information regarding the innate characteristics of the sources and their propagation is essential. Moreover, any SHM system which is expected to transition to field operation must take into account the influence of environmental and operational changes which cause modifications in the stiffness and damping of the structure and consequently modify its dynamic behaviour. On that account, special attention is paid in this paper to the development of an efficient SHM methodology where robust signal processing and pattern recognition techniques are integrated for the correct interpretation of complex ultrasonic waves within the context of damage detection and identification. The methodology is based on an acousto-ultrasonics technique where the discrete wavelet transform is evaluated for feature extraction and selection, linear principal component analysis for data-driven modelling and self-organizing maps for a two-level clustering under the principle of local density. At the end, the methodology is experimentally demonstrated and results show that all the damages were detectable and i

Reconstrucción paleoclimática y paleoambiental de la Península Ibérica durante el Cuaternario, aplicación de modelos geoprospectivos para la evaluación de escenarios futuros

Esta comunicación trata de resumir el trabajo realizado por el ITGE, BRGM, CCMA, IPE, ETSIMM y ENRESA en el proyecto titulado "Paleoclimatological Revision of Climate Evolution and Environment in Western Mediterranean Region. Evaluation of future evolution scenarios in the Iberian Peninsula", en el marco del Programa de la Comisión de las Comunidades Europeas sobre Gestión y Almacenamiento de Residuos Radioactivos (contrato CEC FI2WCT91- 0075)

A specific protein-enriched enteral formula decreases cortisolemia and improves plasma albumin and amino acid concentrations in elderly patients

<p>Abstract</p> <p>Background</p> <p>Old age is associated with an involuntary and progressive but physiological loss of muscle mass. The aim of this study was to evaluate the effects of exclusive consumption for 6 months of a protein-enriched enteral diet with a relatively high content of branched-chain amino acids on albuminemia, cortisolemia, plasma amino acids, insulin resistance, and inflammation biomarkers in elderly patients.</p> <p>Methods</p> <p>Thirty-two patients from the Clinical Nutrition Outpatient Unit at our hospital exclusively consumed a protein-enriched enteral diet for 6 months. Data were collected at baseline and at 3 and 6 months on anthropometric and biochemical parameters and on plasma concentrations of amino acids, cortisol, adrenocorticotropic hormone, urea, creatinine, insulin resistance, and inflammation biomarkers.</p> <p>Results</p> <p>The percentage of patients with albumin concentration below normal cut-off values decreased from 18% to 0% by the end of the study. At 6 months, concentrations of total plasma (<it>p </it>= 0.008) and essential amino acids (<it>p </it>= 0.011), especially branched-chain amino acids (<it>p </it>= 0.031), were higher versus baseline values, whereas 3-methylhistidine (<it>p </it>= 0.001), cortisol (<it>p </it>= 0.001) and adrenocorticotropic hormone (<it>p </it>= 0.004) levels were lower.</p> <p>Conclusions</p> <p>Regular intake of specific protein-enriched enteral formula increases plasma essential amino acids, especially branched-chain amino acids, and decreases cortisol and 3-methylhistidine, while plasma urea and creatinine remain unchanged.</p