Browsing by Subject "PCA"

Now showing 1 - 4 of 4
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    Análisis ACP, CHAID y PLS-SEM de la satisfacción de visitantes de espacios naturales protegidos. Aplicación al Parque Nacional de Aigüestortes en Lleida
    (Murcia: Servicio de publicaciones de la Universidad de Murcia, 2020) Florensa Guiu, Rosa M.; Florensa Guiu, Antonio; Maza Rubio, María Teresa
    La satisfacción de los visitantes de ENP, está influenciada por variables cuantitativas y cualitativas que deben identificarse y analizarse para su optimización. El objeto de este trabajo es analizarlas en el uso público de los ENP, en aplicación al Parque Nacional de Aigüestortes.Se han estudiado las variables explicativas con el Análisis de Componentes Principa-les, la Chi-cuadrado Detección Automática de Interacciones y el PLS-SEM, para valorar su influencia y explicación de la satisfacción y fidelización del visitante ecoturístico. Se demuestra un gran reflejo de las variables medibles valor global, recomendaciones y satisfacción a través de la gente, en la variable dependiente Satisfacción Global del Visitante.
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    Erosión y desertificación.-Estimación de la susceptibilidad a la erosión y desertificación en zonas húmedas mediante radiometría VNIR.
    Córdoba-Sola, P.; Navarro-Pedreño, J.; Gómez-Lucas, I.; Mataix-Beneyto, J.; Universidad de Murcia
    ABSTRACT A multispectral technology as tool for assessing the susceptibility to erosion and desertification in humid zones from the European Mediterranean was applied by means of the use of spectral reflectance data to determine the contents of different attributes of the soils. A collection of field electromagnetic spectrums were obtained from 25 covers of soil, a derivative analysis was applied to electromagnetic spectrums and finally a PCA was made. The results showed good correlations (R2>0,5) between properties of soil and electromagnetic spectrums, therefore it is possible to determine the content of these soil attributes with spectral analysis, which minimizes cost and time.
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    Forensic examination of textile fibres using Raman imaging and multivariate analysis
    (Elsevier B.V., 2021-12-03) Ortega-Ojeda, Fernando E.; García-Ruiz, Carmen; Zapata Arráez, Félix; Química Analítica; Facultades,Servicios y Escuelas::Facultades de la UMU::Facultad de Química
    Vibrational spectroscopic techniques have shown to be highly suitable for the identification and comparison of textile fibres and clothing fabrics. On the other hand, new chemical imaging modes based on these spectroscopic techniques are becoming useful in multiple fields. This is particularly important to, for instance, chemically visualize and screen different samples including forensic evidence (crime scene investigation), chemical and food products (quality control), biological tissues and living beings (medical imaging), among others. This study explores the forensic examination and selective chemical visualization of textile fibres and clothing fabrics using Raman imaging. Four experiments were performed, which were focused on the screening of (i) white different materials made of 100 % cotton (gauze, cotton wool, t-shirt, and swab), (ii) polyester and cotton fabrics evidence of the same colour, (iii) five different coloured cotton fabrics, and (iv) textile fibres of different materials (acrylic, cotton, nylon, polyester, and silk). Several methods of multivariate chemometric analysis including principal component analysis (PCA), multivariate analysis of variance (MANOVA), and multivariate curve resolution (MCR) were applied to enhance the limited visual comparison of the spectra accomplished with the unaided eye. The results evidenced the suitability of Raman imaging to statistically discriminate textile fibres and fabrics due to the chemical composition of both the clothing material and the dyestuff.
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    Herramientas estadísticas para la evaluación del impacto ambiental de la acuicultura
    (2018-12-26) Sanz-Lazaro, Carlos; Facultad de Biología
    GUión para realizar diversas rutinas estadísticas univariantes y multivariantes utilizando datos de macrofauna bentónica y variables ambientales de muestreos que son básicas en la evaluación ambiental de la acuicultura