872 resultados para Online and off-line diagnosis and monitoring methods


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The aim of this thesis is to propose a novel control method for teleoperated electrohydraulic servo systems that implements a reliable haptic sense between the human and manipulator interaction, and an ideal position control between the manipulator and the task environment interaction. The proposed method has the characteristics of a universal technique independent of the actual control algorithm and it can be applied with other suitable control methods as a real-time control strategy. The motivation to develop this control method is the necessity for a reliable real-time controller for teleoperated electrohydraulic servo systems that provides highly accurate position control based on joystick inputs with haptic capabilities. The contribution of the research is that the proposed control method combines a directed random search method and a real-time simulation to develop an intelligent controller in which each generation of parameters is tested on-line by the real-time simulator before being applied to the real process. The controller was evaluated on a hydraulic position servo system. The simulator of the hydraulic system was built based on Markov chain Monte Carlo (MCMC) method. A Particle Swarm Optimization algorithm combined with the foraging behavior of E. coli bacteria was utilized as the directed random search engine. The control strategy allows the operator to be plugged into the work environment dynamically and kinetically. This helps to ensure the system has haptic sense with high stability, without abstracting away the dynamics of the hydraulic system. The new control algorithm provides asymptotically exact tracking of both, the position and the contact force. In addition, this research proposes a novel method for re-calibration of multi-axis force/torque sensors. The method makes several improvements to traditional methods. It can be used without dismantling the sensor from its application and it requires smaller number of standard loads for calibration. It is also more cost efficient and faster in comparison to traditional calibration methods. The proposed method was developed in response to re-calibration issues with the force sensors utilized in teleoperated systems. The new approach aimed to avoid dismantling of the sensors from their applications for applying calibration. A major complication with many manipulators is the difficulty accessing them when they operate inside a non-accessible environment; especially if those environments are harsh; such as in radioactive areas. The proposed technique is based on design of experiment methodology. It has been successfully applied to different force/torque sensors and this research presents experimental validation of use of the calibration method with one of the force sensors which method has been applied to.

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Gear rattle is a phenomenon that occurs when idling or lightly loaded gears collide due to engine’s torque fluctuations. This behaviour is related to vibration behaviour of the transmission system. Aim of this master’s thesis is to evaluate Adams and Adams/Machinery as a simulation tools for modelling the rattle e ect in a transmission system. A case study of tractor’s power take-o driveline, suspected to be prone to rattle, is performed in this work. Modelling methods used by Adams in this type of study are presented in the theory section while simulation model build with the software during this work is presented in the results. The Machinery toolbox is used to create gears and bearings while other model components are created with standard Adams tool set. Geometries and excitations are exported from other softwares. Results were obtained from multiple variations of a base model. These result sets and literature review suggest that Adams/Machinery may not be the most suitable tool for rattle analysis. While the system behaviour was partially captured, for accurate modelling user-written routines must be used which may be more easily performed with other tools. Further research about this topic is required.

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El objetivo de esta investigación es analizar la lealtad de los usuarios de líneas aéreas tanto en el entorno online como en el entorno offline. La revisión bibliográfica ha identificado tres antecedentes: la satisfacción, la confianza y el valor percibido. Se ha llevado a cabo un estudio empírico realizándose un total de 1710 entrevistas personales en el aeropuerto del Prat (Barcelona) a usuarios de dos compañías aéreas tradicionales, Iberia y British Airways, y a una compañía low cost, Easyjet. Se trata de las tres compañías que operan con vuelos directos Barcelona-Londres. En el análisis de los datos se han utilizado modelos de ecuaciones estructurales y en particular la técnica utilizada fue el análisis factorial confirmatorio. Los resultados revelan que tanto la satisfacción, como la confianza y el valor percibido explican las relaciones de lealtad entre los pasajeros y las compañías aéreas.

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This article compares the results obtained from using two different methodological approaches to elicit teachers’ views on their professional role, the key challenges and their aspirations for the future. One approach used a postal/online questionnaire, while the other used telephone interviews, posing a selection of the same questions. The research was carried out on two statistically comparable samples of teachers in England in spring 2004. Significant differences in responses were observed which seem to be attributable to the methods employed. In particular, more ‘definite’ responses were obtained in the interviews than in response to the questionnaire. This article reviews the comparative outcomes in the context of existing research and explores why the separate methods may have produced significantly different responses to the same questions.

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A fully automated and online artifact removal method for the electroencephalogram (EEG) is developed for use in brain-computer interfacing. The method (FORCe) is based upon a novel combination of wavelet decomposition, independent component analysis, and thresholding. FORCe is able to operate on a small channel set during online EEG acquisition and does not require additional signals (e.g. electrooculogram signals). Evaluation of FORCe is performed offline on EEG recorded from 13 BCI particpants with cerebral palsy (CP) and online with three healthy participants. The method outperforms the state-of the-art automated artifact removal methods Lagged auto-mutual information clustering (LAMIC) and Fully automated statistical thresholding (FASTER), and is able to remove a wide range of artifact types including blink, electromyogram (EMG), and electrooculogram (EOG) artifacts.

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Geophysics has been shown to be effective in identifying areas contaminated by waste disposal, contributing to the greater efficiency of soundings programs and the installation of monitoring wells. In the study area, four trenches were constructed with a total volume of about 25,000 m(3). They were almost totally filled with re-refined lubricating oil waste for approximately 25 years. No protection liners were used in the bottoms and laterals of the disposal trenches. The purpose of this work is to evaluate the potential of the resistivity and ground penetrating radar (GPR) methods in characterizing the contamination of this lubricant oil waste disposal area in Ribeiro Preto, SP, situated on the geological domain of the basalt spills of the Serra Geral Formation and the sandstones of the Botucatu Formation. Geophysical results were shown in 2D profiles. The geophysical methods used enabled the identification of geophysical anomalies, which characterized the contamination produced by the trenches filled with lubricant oil waste. Conductive anomalies (smaller than 185 Omega m) immediately below the trenches suggest the action of bacteria in the hydrocarbons, as has been observed in several sites contaminated by hydrocarbons in previously reported cases in the literature. It was also possible to define the geometry of the trenches, as evidenced by the GPR method. Direct sampling (chemical analysis of the soil and the water in the monitoring well) confirmed the contamination. In the soil analysis, low concentrations of several polycyclic aromatic hydrocarbons (PAHs) were found, mainly naphthalene and phenanthrene. In the water samples, an analysis verified contamination of the groundwater by lead (Pb). The geophysical methods used in the investigation provided an excellent tool for environmental characterization in this study of a lubricant oil waste disposal area, and could be applied in the study of similar areas.

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Al(2)O(3):Eu(3+)(1%) samples were prepared by combustion, ceramic, and Pechini methods annealed from 400 to 1400 degrees C. XRD patterns indicate that samples heated up to 1000 degrees C present disordered character of activated alumina (gamma-Al(2)O(3)). However, alpha-Al(2)O(3) phase showed high crystallinity and thermostability at 1200-1400 degrees C. The sample characterizations were also carried out by means of infrared spectroscopy (IR), scanning electron microscopy (SEM) and specific surface areas analysis (BET method). Excitation spectra of Al(2)O(3):Eu(3+) samples present broaden bands attributed to defects of Al(2)O(3) matrices and to LMCT state of O -> Eu(3+), however, the narrow bands are assigned to (7)F(0) -> (5)D(J),(5)H(J) and (5)L(J) transitions of Eu(3+) ion. Emission spectra of samples calcined up to 1000 degrees C show broaden bands for (5)D(0) -> (7)F(J) transitions of Eu(3+) ion suggesting that the rare earth ion is in different symmetry sites showed by inhomogeneous line broadening of bands, confirming the predominance of the gamma-alumina phase. For all samples heated from 1200 to 1400 degrees C the spectra exhibit narrow (5)D(0) -> (7)F(J) transitions of Eu(3+) ion indicating the conversion of gamma to alpha-Al(2)O(3) phases, a high intensity narrow peak around 695 nm assigned to R lines of Cr(3+) ion is shown. Al(2)O(3):Eu(3+) heated up to 1100 degrees C presents an increase in the Omega(2) intensity parameter with the increase of temperatures enhancing the covalent character of metal-donor interaction. The disordered structural systems present the highest values of emission quantum efficiencies (eta). CIE coordinates of Al(2)O(3):Eu(3+) are also discussed. (C) 2007 Elsevier Inc. All rights reserved.

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Chemical and spectroscopic methods were used to characterize organic matter transformations during the composting process. Four different residue mixtures were studied: P1 - garden trimmings (GT) only, P2 - GT plus fresh cattle manure, P3 - GT plus orange pomace and P4 - GT plus filter cake. The thermophilic phase was not reached in PI compost, but the P2, P3 and P4 composts showed all three typical process phases. The thermophilic phase and CEC/C ratio stabilized after 90 days, while C/N ratio and the ash content stabilized after 60 days. The increasing E(4)/E(6) ratio indicated oxidation reactions occurring during the process in the material from P2, P3 and P4. The (13)C NMR and FTIR results suggested extraction of both pectin and lignin in the HA-like fraction. The CEC/C ratio, temperature and E(4)/E(6) ratio showed that within 90 days P2, P3 and P4 composts were humified. However, material from P1 did not show characteristics of humified compost. From these data, it is apparent that C/N ratio and ash content are not reliable methods for monitoring the composting process. (C) 2009 Elsevier Ltd. All rights reserved.

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O presente trabalho explora as causas pelas quais o campo da moda plus size carece de legitimidade com as consumidoras plus size. Eu explorei o assunto em três artigos. No primeiro, eu estudo o processo de legitimação de um novo mercado emergente, o mercado da moda plus size brasileira e os desafios para sua a institucionalização. Eu conduzi dezessete entrevistas com consumidoras plus size, uma netnografia em quatro blogs de moda plus size brasileiros e analisei de maneira semiótica um site que vende roupas de moda plus size. Meus resultados indicam que, apesar de ter atores legítimos que promovem essas marcas de moda plus size, o campo da moda plus size ainda é percebido como uma versão vergonhosa do campo da moda. Defendo aqui que o fato de uma das lógicas de campo da moda plus size ser estigma, acaba afetando os projetos identitários das consumidoras de maneira depreciativa, de forma elas não se envolvem em práticas de capital cultural que ocorrem dentro do campo da moda plus size. No segundo artigo, eu conduzi uma introspecção genealógica em que eu pesquisei questões de identidade. Como uma mulher (que se assume ) plus size, eu imaginei que seria relevante para olhar para dentro de mim mesma, a fim de explorar a forma como a minha identidade liga-se com a rede semiótica-material que me rodeia em termos de moda, alimentos e outros elementos. Meus dados vieram tanto de técnicas de introspecção simultâneas, quanto retrospectivas. Em termos teóricos, eu usei a ideia de ―assemblages‖ e eu foquei minha análise tanto nos aspectos materiais da minha rede de consumo, quanto na estabilidade da rede. As consequências da minha assemblage estão ligadas a uma gestão de qualidade total da minha identidade, tanto online como off-line, refletidas em práticas de consumo que se conectam à ideia de uma lógica de consumo bulímica em que o consumo de alimentos e gestão corpo estão interligadas. Por fim, no meu terceiro artigo, eu explorei o conceito de identidade a partir do consumo da moda feminina plus size. Foram feitas catorze entrevistas fenomenológicas, cujos dados foram analisados a partir de uma perspectiva hermenêutica. Três categorias temáticas emergiram da análise de dados: a construção da identidade por meio da moda, elementos de identidade plus size e estratégias criativas para lidar com a falta de produtos para mulheres plus size no varejo. Entre os principais resultados, destacam-se a forma como o termo plus size atua como estigma, influenciando projetos de identidade das consumidoras, o papel do varejo no processo de estigmatização e a saga épica de compras, que envolve um "mercado negro", com a participação de vendedores. Eu concluo discutindo o papel da identidade na instabilidade do campo da moda plus size.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Tigecycline is a new glycylcycline with an expanded broad-spectrum antibiotic, including inhibition of Gram-positive, Gram-negative, atypical, anaerobic, and antibiotic-resistant organisms. Trials have demonstrated that tigecycline is noninferior to the comparators for the treatment of complicated skin and skin structure infections as well as complicated intra-abdominal infections. Tigecycline is only available as an intravenous preparation and analytical methods to its quantitation in pharmaceutical products has not been published to date. This review examined tigecycline characteristics, the spectrum and mechanism of action, pharmacokinetics, applications, and, mainly, the instrumental conditions of published chromatographic methods used to measure tigecycline, its metabolites, and some analogs in clinical and biologic research.

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A fast, sensitive and cost-effective multiplex-PCR assay for Mycobacterium tuberculosis complex (MTC) and Mycobacterium avium (M. avium) identification for routine diagnosis was evaluated. A total of 158 isolates of mycobacteria from 448 clinical specimens from patients with symptoms of mycobacterial disease were analyzed. By conventional biochemical methods 151 isolates were identified as M. tuberculosis, five as M. avium and two as Mycobacterium chelonae (M. chelonae). Mycolic acid patterns confirmed these results. Multiplex-PCR detected only IS6110 in isolates identified as MTC, and IS1245 was found only in the M. avium isolates. The method applied to isolates from two patients, identified by conventional methods and mycolic acid analysis, one as M. avium and other as M. chelonae, resulted positive for IS6110, suggesting co-infection with M. tuberculosis. These patients were successfully submitted to tuberculosis treatment. The multiplex-PCR method may offer expeditious identification of MTC and M. avium, which may minimize risks for active transmission of these organisms and provide useful treatment information.

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The Candida genus expresses virulence factors that, when combined with immunosuppression and other risk factors, can cause different manifestations of oral candidiasis. The treatment of mucosal infections caused by Candida and the elucidation of the disease process have proven challenging. Therefore, the study of experimentally induced oral candidiasis in rats and mice is useful to clarify the etiopathology of this condition, improve diagnosis, and search for new therapeutic options because the disease process in these animals is similar to that of human candidiasis lesions. Here, we describe and discuss new studies involving rat and mouse models of oral candidiasis with respect to methods for inducing experimental infection, methods for evaluating the development of experimental candidiasis, and new treatment strategies for oral candidiasis. © 2013 Landes Bioscience.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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A pursuer UAV tracking and loitering around a target is the problem analyzed in this thesis. The UAV is assumed to be a fixed-wing vehicle and constant airspeed together with bounded lateral accelerations are the main constraints of the problem. Three different guidance laws are designed for ensuring a continuos overfly on the target. Different proofs are presented to demonstrate the stability properties of the laws. All the algorithms are tested on a 6DoF Pioneer software simulator. Classic control design methods have been adopted to develop autopilots for implementig the simulation platform used for testing the guidance laws.