3 resultados para Analysis of principal component
em Repositório Científico da Universidade de Évora - Portugal
Resumo:
Objective. To culturally adapt and validate a version in European Portuguese language of the HIV Antibody Testing Attitude Scale. Methods. Study conducting a methodological investigation for the adaptation and validation of an attitude measurement instrument. The instrument translation and back-translation were performed. Then, a pre-test was conducted. The study used a sample of 317 subjects from the academic community - students, professors and other professionals - who were contacted in the campus. Ethical principles were observed. Results. Three analyses were conducted using the method of principal component analysis (PCA) with five, four and three factors. A three-factor solution was achieved, which presents 50.82% variance. In the analysis of inter-item correlation, values between -0.018 and 0.749 were observed. Internal consistency shows Cronbach’s alpha coefficients of 0.860 overall and between 0.865 and 0.659 in the three factors. Conclusion. The instrument version shows psychometric properties that allow its use in Portuguese-speaking countries.
Resumo:
Subtle structural differencescan be observed in the islets of Langer-hans region of microscopic image of pancreas cell of the rats having normal glucose tolerance and the rats having pre-diabetic(glucose intolerant)situa-tions. This paper proposes a way to automatically segment the islets of Langer-hans region fromthe histological image of rat's pancreas cell and on the basis of some morphological feature extracted from the segmented region the images are classified as normal and pre-diabetic.The experiment is done on a set of 134 images of which 56 are of normal type and the rests 78 are of pre-diabetictype. The work has two stages: primarily,segmentationof theregion of interest (roi)i.e. islets of Langerhansfrom the pancreatic cell and secondly, the extrac-tion of the morphological featuresfrom the region of interest for classification. Wavelet analysis and connected component analysis method have been used for automatic segmentationof the images. A few classifiers like OneRule, Naïve Bayes, MLP, J48 Tree, SVM etc.are used for evaluation among which MLP performed the best.
Resumo:
A photovoltaic cell is a component which converts light energy into electrical energy. Different environmental parameters and internal parameters have a great impact on the output of the photovoltaic cell. To identify its characteristics and estimate the output, the well known Shockley diode equation is used. This equation contains all the parameters, as one environmental and different internal. The properties of these parameters were studied and their sensitivity have been analyzed through the use of an error function; this error function allows the study of the behaviour of the parameters and their characteristics against the output of the photovoltaic cell through the analysis of its curves giving the sensitivity of the different parameters to the output of the photovoltaic cell. Using these results the impact of the parameters of the photovoltaic cell has been clearly identified. White noise is included both with the ideal values and the simulation and the ideal value is imposed to get the real time environment flavor. This work analyses both systems with and without white noise.