61 resultados para Catàlisi bioinspirada
Resumo:
The oxidative addition proved to be a useful method to prepare platinum (II) hydridotiolate by reaction of tetrakis(triphenylphosphine)platinum(0) with aminothiolate and phosphinothiolate ligands like cysteamine, cysteine ethyl and methyl Esther, 2-(diphenylphosphino)ethanetiol and 2-(diphenylphosphino)propanetiol. The complexes are square-planar and the aminothiolate or phosphinothiolate ligands are chelated to platinum (II). The hydrido ligand is trans to the sulfur and the other coordination position is occuped by a triphenylphosphine ligand. The complexes are mononuclear and they show low symmetry. The only symmetry element, the plan is broke if the ligand is branched, obtaining asymmetric complexes C1. If the ligand has electronic or esteric impediments the reaction doesn't run and the starting products are recovered. This was observed with N,N-dimethylcysteamine and penicylamine methyl esther ligands. In the special case of orthoaminotiophenol the hydridotiolate was obtained but the ligand was not chelated. The aminothiolate complexes don't show solution equilibrium. Otherwise, the complexe with 2-(diphenylphosphino)ethanetiol show an isomerisation equilibrium which forms cis isomer as a minor component. The complexe with 2-(diphenylphosphino)-propanetiol shows a conformational equilibrium between chair and twist forms. The complexes have been tested as catalyst precursors in hydroformylation and hydrosilylation reactions. The hydroformylation reaction runs only in presence of SnCl2 as cocatalyst. Catalytic activity depends on the presence of triphenylphosphine and, with less magnitude, CO and H2 pressure. We also studied the enantioselectivity using a chiral complexe. In the hydrosililation reaction, catalysts run with good results (<90%) using triethylsilane as silicon hydride. Dehydrogenative addition product has been also found in this reaction.
Resumo:
Este artigo apresenta uma breve revisão de alguns dos mais recentes métodos bioinspirados baseados no comportamento de populações para o desenvolvimento de técnicas de solução de problemas. As metaheurísticas tratadas aqui correspondem às estratégias de otimização por colônia de formigas, otimização por enxame de partículas, algoritmo shuffled frog-leaping, coleta de alimentos por bactérias e colônia de abelhas. Os princípios biológicos que motivaram o desenvolvimento de cada uma dessas estratégias, assim como seus respectivos algoritmos computacionais, são introduzidos. Duas aplicações diferentes foram conduzidas para exemplificar o desempenho de tais algoritmos. A finalidade é enfatizar perspectivas de aplicação destas abordagens em diferentes problemas da área de engenharia.
Resumo:
El reto de implantar los nuevos grados exige un continuado esfuerzo de coordinación de las asignaturas de cada curso y de los diferentes cursos entres sí. En este trabajo se presentan los resultados de los diferentes proyectos que se han realizado para coordinar las asignaturas de los tres primeros cursos del Grado en Ingeniería en Sonido e Imagen en Telecomunicación de la Escuela Politécnica Superior. Además se analiza la coordinación de los proyectos entre sí, analizando los cambios surgidos en las fichas de las asignaturas, evaluación, metodología, etc. También se presenta una puesta en común con los coordinadores de todos los cursos para realizar las recomendaciones de matriculación a los estudiantes que realizan su matrícula a tiempo parcial o no superan cada curso todos los créditos matriculados. Y por último, se estudia la continuidad con los contenidos de las asignaturas que comienzan su implantación en el siguiente curso y por otro lado la coordinación en la evaluación para eliminar las numerosas coincidencias de evaluaciones continuas, de diferentes actividades en cada semana.
Resumo:
The growing demand for physical rehabilitation processes can result in the rising of costs and waiting lists, becoming a threat to healthcare services’ sustainability. Telerehabilitation solutions can help in this issue by discharging patients from points of care while improving their adherence to treatment. Sensing devices are used to collect data so that the physiotherapists can monitor and evaluate the patients’ activity in the scheduled sessions. This paper presents a software platform that aims to meet the needs of the rehabilitation experts and the patients along a physical rehabilitation plan, allowing its use in outpatient scenarios. It is meant to be low-cost and easy-to-use, improving patients and experts experience. We show the satisfactory results already obtained from its use, in terms of the accuracy evaluating the exercises, and the degree of users’ acceptance. We conclude that this platform is suitable and technically feasible to carry out rehabilitation plans outside the point of care.
Growing Neural Gas approach for obtaining homogeneous maps by restricting the insertion of new nodes
Resumo:
The Growing Neural Gas model is used widely in artificial neural networks. However, its application is limited in some contexts by the proliferation of nodes in dense areas of the input space. In this study, we introduce some modifications to address this problem by imposing three restrictions on the insertion of new nodes. Each restriction aims to maintain the homogeneous values of selected criteria. One criterion is related to the square error of classification and an alternative approach is proposed for avoiding additional computational costs. Three parameters are added that allow the regulation of the restriction criteria. The resulting algorithm allows models to be obtained that suit specific needs by specifying meaningful parameters.
Resumo:
The lower urinary tract is one of the most complex biological systems of the human body as it involved hydrodynamic properties of urine and muscle. Moreover, its complexity is increased to be managed by voluntary and involuntary neural systems. In this paper, a mathematical model of the lower urinary tract it is proposed as a preliminary study to better understand its functioning. Furthermore, another goal of that mathematical model proposal is to provide a basis for developing artificial control systems. Lower urinary tract is comprised of two interacting systems: the mechanical system and the neural regulator. The latter has the function of controlling the mechanical system to perform the voiding process. The results of the tests reproduce experimental data with high degree of accuracy. Also, these results indicate that simulations not only with healthy patients but also of patients with dysfunctions with neurological etiology present urodynamic curves very similar to those obtained in clinical studies.
Resumo:
Power line interference is one of the main problems in surface electromyogram signals (EMG) analysis. In this work, a new method based on the stationary wavelet packet transform is proposed to estimate and remove this kind of noise from EMG data records. The performance has been quantitatively evaluated with synthetic noisy signals, obtaining good results independently from the signal to noise ratio (SNR). For the analyzed cases, the obtained results show that the correlation coefficient is around 0.99, the energy respecting to the pure EMG signal is 98–104%, the SNR is between 16.64 and 20.40 dB and the mean absolute error (MAE) is in the range of −69.02 and −65.31 dB. It has been also applied on 18 real EMG signals, evaluating the percentage of energy respecting to the noisy signals. The proposed method adjusts the reduction level to the amplitude of each harmonic present in the analyzed noisy signals (synthetic and real), reducing the harmonics with no alteration of the desired signal.
Resumo:
The development of applications as well as the services for mobile systems faces a varied range of devices with very heterogeneous capabilities whose response times are difficult to predict. The research described in this work aims to respond to this issue by developing a computational model that formalizes the problem and that defines adjusting computing methods. The described proposal combines imprecise computing strategies with cloud computing paradigms in order to provide flexible implementation frameworks for embedded or mobile devices. As a result, the imprecise computation scheduling method on the workload of the embedded system is the solution to move computing to the cloud according to the priority and response time of the tasks to be executed and hereby be able to meet productivity and quality of desired services. A technique to estimate network delays and to schedule more accurately tasks is illustrated in this paper. An application example in which this technique is experimented in running contexts with heterogeneous work loading for checking the validity of the proposed model is described.
Resumo:
En esta memoria se describe el proyecto llevado a cabo para mejorar el seguimiento y la calidad de la docencia de las asignaturas del tercer curso del Grado en Ingeniería Informática. En concreto, en este proyecto, nos centramos en los mecanismos de evaluación y en su distribución a lo largo del curso, así como en los conceptos fundamentales que se asocian a las diferentes asignaturas que se imparten en tercer curso del Grado en Ingeniería Informática. Se realizaron diversas reuniones entre los coordinadores de las distintas asignaturas para poner en común problemas relacionados con la planificación de las asignaturas así como dudas sobre las actividades de evaluación. Las reuniones permitieron intercambiar diferentes planteamientos con los que se habían abordado la evaluación de las asignaturas participantes en la red y que posibilitaron resolver problemas comunes. De igual forma se plantearon cuestiones abiertas sobre la planificación y la evaluación de las asignaturas que se dirigieron desde la red a la coordinación de la titulación en la Escuela Politécnica Superior. Finalmente, también se discutieron diferentes propuestas junto con las redes de otros cursos de la titulación para abordarlas en futuras redes.
Resumo:
En esta memoria se describe el trabajo de la red docente para el seguimiento y control de calidad de las asignaturas del segundo curso del Grado en Ingeniería Informática impartido en la Escuela Politécnica Superior de la Universidad de Alicante. En esta edición, el trabajo de la red se ha centrado en el estudio de las necesidades formativas y los contenidos impartidos en las asignaturas. El resultado ha sido la creación de un grafo de dependencias entre asignaturas de segundo y primer curso (y de segundo curso entre sí), un mapa de necesidades formativas para acceder a las asignaturas de segundo curso y un mapa de los contenidos impartidos en éstas. Asimismo, se ha elaborado un calendario on-line de evaluaciones para el curso 2014-2015.
Resumo:
El trabajo de esta Red Docente se ha planteado como una continuación directa del realizado en el marco de la Red Docente 2733, del curso pasado. Continuamos con la elaboración del mapa conceptual, en el que ahora vamos a identificar solapamientos y lagunas en los conocimientos del egresado en el Grado en Ingeniería Informática. Por otro lado hemos simplificado y mejorado la gestión del calendario de evaluación, en el que se reflejan todas las pruebas evaluables que realizan los alumnos de la titulación, con el objetivo de mejorar la coordinación y evitar la excesiva concentración de pruebas en un reducido período de tiempo.
Resumo:
Abdominal Aortic Aneurism is a disease related to a weakening in the aortic wall that can cause a break in the aorta and the death. The detection of an unusual dilatation of a section of the aorta is an indicative of this disease. However, it is difficult to diagnose because it is necessary image diagnosis using computed tomography or magnetic resonance. An automatic diagnosis system would allow to analyze abdominal magnetic resonance images and to warn doctors if any anomaly is detected. We focus our research in magnetic resonance images because of the absence of ionizing radiation. Although there are proposals to identify this disease in magnetic resonance images, they need an intervention from clinicians to be precise and some of them are computationally hard. In this paper we develop a novel approach to analyze magnetic resonance abdominal images and detect the lumen and the aortic wall. The method combines different algorithms in two stages to improve the detection and the segmentation so it can be applied to similar problems with other type of images or structures. In a first stage, we use a spatial fuzzy C-means algorithm with morphological image analysis to detect and segment the lumen; and subsequently, in a second stage, we apply a graph cut algorithm to segment the aortic wall. The obtained results in the analyzed images are pretty successful obtaining an average of 79% of overlapping between the automatic segmentation provided by our method and the aortic wall identified by a medical specialist. The main impact of the proposed method is that it works in a completely automatic way with a low computational cost, which is of great significance for any expert and intelligent system.
Resumo:
Background and objective: In this paper, we have tested the suitability of using different artificial intelligence-based algorithms for decision support when classifying the risk of congenital heart surgery. In this sense, classification of those surgical risks provides enormous benefits as the a priori estimation of surgical outcomes depending on either the type of disease or the type of repair, and other elements that influence the final result. This preventive estimation may help to avoid future complications, or even death. Methods: We have evaluated four machine learning algorithms to achieve our objective: multilayer perceptron, self-organizing map, radial basis function networks and decision trees. The architectures implemented have the aim of classifying among three types of surgical risk: low complexity, medium complexity and high complexity. Results: Accuracy outcomes achieved range between 80% and 99%, being the multilayer perceptron method the one that offered a higher hit ratio. Conclusions: According to the results, it is feasible to develop a clinical decision support system using the evaluated algorithms. Such system would help cardiology specialists, paediatricians and surgeons to forecast the level of risk related to a congenital heart disease surgery.
Resumo:
El fomento de la calidad universitaria es una dimensión clave en el EEES que se basa en sistemas de garantía y mejora de la calidad internos en las universidades y en procedimientos llevados a cabo por agencias de evaluación y acreditación externas a ellas. Además, se resalta que cada vez es más necesario que estas acreditaciones de calidad nacionales se reconozcan fuera del propio país. En este contexto ha surgido la creación de sellos de calidad europeos que están enfocados a determinados sectores científico-técnicos o profesionales que tienen la ventaja de facilitar la comparación transfronteriza y ofrecer a universidades y egresados la posibilidad de demostrar la calidad de sus titulaciones en el ámbito europeo. En el caso de los Grados en Ingeniería Informática es el sello EURO-INF regulado por la European Quality Assurance Network for Informatics Education (EQANIE) el que garantiza que la calidad de los programas en informática se corresponde con los criterios europeos genéricos establecidos y que sus egresados adquieren las competencias definidas para este sello. En esta memoria se explica el trabajo realizado para el proceso de acreditación y solicitud del sello EURO-INF como un doble proceso aprovechando las sinergias entre ambos procedimientos.
Resumo:
En este artículo se describe el trabajo realizado por la red de investigación en docencia universitaria denominada “Docencia semipresencial en el Máster en Ingeniería Informática” y que ha pretendido trabajar en las diferentes asignaturas del Máster en Ingeniería Informática de la Universidad de Alicante con el fin de dotarlas de un carácter semipresencial de una forma coordinada e integrada. Se ha creado un grupo de trabajo dentro de la comisión académica del máster y se ha impulsado una colaboración estrecha entre los responsables de todas las asignaturas del Máster en Ingeniería Informática a la hora de usar todos los mecanismos necesarios para dotar a las respectivas asignaturas del carácter semipresencial. Ha sido muy importante el apoyo que se ha tenido del ICE en este sentido, por ejemplo mediante la solicitud y realización de un curso específico sobre bLearning.