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Capítulo de livro Extracting discriminant information from neuroimages: A multivariate computational framework to analyze the whole human brain(2010-01-05) Carlos E. Thomaz; LEÃO, R. D.; SATO, J. R.; BUSATTO, G. F.© 2010 Nova Science Publishers, Inc.With the increasing anatomical resolution of the neuroimaging methods, clinicians are challenged nowadays, more than ever before, with the problem of detecting and interpreting statistically significant changes on neuroimages that are often distributed and involve simultaneously several structures of the human brain. In this chapter, we describe a general multivariate linear framework that analyses all the data simultaneously rather than segmented versions separately or feature-by-feature. This approach has been specially designed for extracting discriminative information from high dimensional data, dealing with the problem of small sample sizes, and it has been successfully applied in MR imaging analysis of the human brain. The multivariate linear framework is not restricted to any particular set of features and describes a simple and straightforward way of explaining multivariate changes of the whole brain on the original MR image domain, giving results that are statistically relevant to be further validated and interpreted by clinicians.Capítulo de livro A New Biomarker for Alzheimer’s Based on the Hippocampus Image Through the Evaluation of the Surface Charge Distribution(2019-01-05) BELARDI, A. A.; DE O. FREITAS, F.; BECHELLI, R. P.; PIVA, R. G. G.© 2020 by Taylor & Francis Group, LLC.Alzheimer’s disease causes losses of the gray material and hippocampus is one of the first regions of the brain to be affected. The objective of this chapter is to present the hippocampus surface charge density distribution as a new approach to analyze hippocampal changes due to Alzheimer’s. We have developed a mathematical model using electrostatics equations together with the method of moments and Haar wavelet to build a practical tool in Matlab, able to efficiently calculate the surface charge densities of hippocampus using the hippocampal masks as input images. We tested the tool in 30 volunteers’ hippocampal masks, obtained from Alzheimer’s Disease Neuroimaging Initiative.Capítulo de livro Information security management based on adaptive security policy using user behavior analysis(2012-01-05) BROSSO, I.; LA NEVE, A.This chapter presents a system for information security management based on adaptative security policy using user's behavior analysis in Information Technology. This system must be able to acquire information about the environment, space, time, equipment, hardware, and software. This information is used in the user behavior analysis. This work proposes that, based on the evidence of the user behavior, it is possible to trust or not trust the user. Levels of trust are released according to the user behavior and the rules that were previously established for the parameters, which help to establish the evidences of behavioral trust, interacting with the environment information, so as to keep trust levels updated in a more accurate and faithful way. © 2012, IGI Global.Capítulo de livro Influence of turbine inlet temperature on the efficiency of externally fired gas turbines(2014-01-01) DE MELLO, P. E. B.; SCUOTTO, S.; DOS SANTOS, O. F.; Gustavo Donato© Springer International Publishing Switzerland 2014.Many researchers have considered externally fired gas turbines (EFGT) as an option for the implementation of biomass-fueled power plants. The EFGT cycle with regeneration or the gas-vapor combined cycle using one EFGT, also known as externally fired combined cycle (EFCC), could lead to significant efficiency improvements if compared to current technology used for power generation from biomass. This work presents one improved numerical model used for the simulation of EFGT cycle. The results were obtained with a numerical model for the EFGT cycle coupled with a model for the high temperature heat exchanger (HTHE) that is necessary for the cycle implementation. The model of the heat exchanger is based in correlations for the Colburn and friction factors, obtained with CFD simulations. In previous work, the model included only laminar regime for the heat exchanger. The present work extends the correlations that describe the behavior of the heat exchanger to turbulent and transitional regimes. The updated model of the EFGT cycle is used to investigate the influence of the turbine inlet temperature over the cycle efficiency. The results obtained confirm that the pressure drop caused by the heat exchanger is one important parameter that influences the cycle efficiency. The feasibility of the EFGT cycle is discussed taking into consideration that the highest temperature in EFGT cycle is not in the turbine inlet, but in the high temperature heat exchanger.