Repetitive Control Meets Continuous Zero Phase Error Tracking Controller for Precise Tracking of B-spline Trajectories

In this paper, a novel repetitive control scheme is presented and discussed, based on the so-called B-spline filters. These dynamic filters are able to generate a B-spline trajectory if they are fed with the sequence of control points defining the curve. Therefore, they are ideal tools for generating online reference signals with the prescribed level of smoothness for driving dynamic systems, possibly together with a feedforward compensator. In particular, a Continuous Zero Phase Error Tracking Controller (ZPETC) can be used for tracking control of non-minimum phase systems but because of its open-loop nature it cannot guarantee the robustness with respect to modeling errors and exogenous disturbances. For this reason, ZPETC and trajectory generator have been embedded in a repetitive control scheme that allows to nullify interpolation errors even in non-ideal conditions, provided that the desired reference trajectory and the disturbances are periodic. Asymptotic stability of the overall control scheme is proved mathematically and experimental validation based on a non-minimum phase system is performed. Different models of the same physical system have been identified and used in the implementation of this model-based control scheme, allowing a real evaluation of the relationship between control system performance and model accuracy

Análise dos aspectos socioeconômicos da Venezuela durante o governo de Hugo Rafael Chávez Frias sob a ótica da economia política do sistema-mundo

TCC (graduação) - Universidade Federal de Santa Catarina. Centro Sócio-Econômico. Economia.Este trabalho de conclusão de curso se propôs analisar uma década de governo de Hugo Chávez Frias na Venezuela sob o aspecto de sua política econômica. Para tanto, utilizou-se do instrumental metodológico da teoria da Economia Política dos Sistemas-Mundo. A questão norteadora consistiu em identificar os aspectos do plano de desenvolvimento socioeconômico do governo Chávez passíveis de análise sob a ótica da Economia Política dos Sistemas-Mundo. Desse modo, o objetivo geral foi analisar o desenvolvimento socioeconômico venezuelano referente ao governo de Hugo Chávez, sob a perspectiva da Economia Política dos Sistemas – Mundo, utilizando a literatura existente sobre essa teoria – especificamente o Grupo de Pesquisa em Economia Política dos Sistemas - Mundo, da Universidade Federal de Santa Catarina – bem como levantando notícias, análises políticas, análises econômicas do governo Chávez, procurando uma perspectiva neutra, por meio de autores críticos e apoiadores do líder venezuelano. A revisão da literatura possibilitou encontrar um governante polêmico, mas realizador, sobretudo nas áreas de educação e saúde. Do ponto de vista da Economia Política dos Sistemas-Mundo, percebe-se uma Venezuela participante, utilizando-se de seu produto básico, o petróleo, para se integrar globalmente à OPEP, relacionando-se comercialmente com países membros e países importadores, de um lado. De outro, a Venezuela posiciona-se regionalmente, buscando a integração econômica com países sul-americanos

Clinical survey of neurosensory side-effects of mandibular parasymphyseal bone harvesting

The aim of the present survey was to assess neurosensory disturbances and/or tooth-pulp sensitivity losses after mandibular parasymphyseal bone-harvesting procedures. Twenty-eight harvesting areas in 16 patients were surveyed. Mucosal and skin sensitivity of the chin/lower lip, divided into four regions, were determined via Pointed-Blunt and Two-Point-Discrimination Tests. Pulp sensitivity of the mandibular teeth from the left second bicuspid to the right second bicuspid was tested by cold vitality preoperatively and 12 months postoperatively. Teeth were grouped according to sensitivity alterations and distance from the harvesting defects, as measured on CT scans, and statistically significant differences sought. At 12 months, 29% of preoperatively vital cuspids overlying the harvesting defects revealed pulp-sensitivity losses; no patient reported anaesthesia or analgesia; hypoaesthesia was present in 4% (8 sites; 2 patients), hypoalgesia was present in 3% (5 sites; 2 patients) and Two-Point-Discrimination Tests yielded pathologic responses in 5% of tested areas (10 sites; 4 patients). Teeth with and without pulp sensitivity changes were statistically indistinguishable regarding distances between root apices or mental foramen and the harvesting defect. The loss of pulp sensitivity in any tooth cannot be predicted simply on the basis of the distance between its apex and the harvesting osteotomy line