46 research outputs found

    Quantifying Robotic Swarm Coverage

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    In the field of swarm robotics, the design and implementation of spatial density control laws has received much attention, with less emphasis being placed on performance evaluation. This work fills that gap by introducing an error metric that provides a quantitative measure of coverage for use with any control scheme. The proposed error metric is continuously sensitive to changes in the swarm distribution, unlike commonly used discretization methods. We analyze the theoretical and computational properties of the error metric and propose two benchmarks to which error metric values can be compared. The first uses the realizable extrema of the error metric to compute the relative error of an observed swarm distribution. We also show that the error metric extrema can be used to help choose the swarm size and effective radius of each robot required to achieve a desired level of coverage. The second benchmark compares the observed distribution of error metric values to the probability density function of the error metric when robot positions are randomly sampled from the target distribution. We demonstrate the utility of this benchmark in assessing the performance of stochastic control algorithms. We prove that the error metric obeys a central limit theorem, develop a streamlined method for performing computations, and place the standard statistical tests used here on a firm theoretical footing. We provide rigorous theoretical development, computational methodologies, numerical examples, and MATLAB code for both benchmarks.Comment: To appear in Springer series Lecture Notes in Electrical Engineering (LNEE). This book contribution is an extension of our ICINCO 2018 conference paper arXiv:1806.02488. 27 pages, 8 figures, 2 table

    Electro-Deposition of Carbon Structures at Mid Voltage and Room Temperature Using Ethanol/Aqueous Solutions

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    Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Direct syntheses of carbon structures including nanodiamond, microdiamond and diamond-like carbon (DLC) on silicon wafers by liquid phase electro-deposition are presented. The solution (ethanol/water) was employed as electrolyte at different concentration levels. Assays were carried out maintaining constant the electric potential between the silicon electrodes in the range of (80-300 V) at current density of approximately 2.0 mA/cm(2). Scanning electron microscopy showed that non-uniform, smooth and heterogeneous structures were produced. The structural composition was evaluated by micro-Raman spectroscopy. A mechanism for the formation of sp(3) and sp(2) hybridizations is proposed. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.066203jes] All rights reserved.1593D159D161Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Mast cell concentration and skin wound contraction in rats treated with Brazilian pepper essential oil (Schinus terebinthifolius Raddi)

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    PURPOSE: To evaluate wound contraction and the concentration of mast cells in skin wounds treated with 5% BPT essential oil-based ointment in rats. METHODS: Twenty rats, male, of adult age, were submitted to skin surgery on the right (RA) and left antimeres (LA) of the thoracic region. They were divided into two groups: control (RA - wounds receiving daily topical application of vaseline and lanolin) and treated (LA - wounds treated daily with the topical ointment). The skin region with wounds were collected at days 4, 7, 14 and 21 after surgery. Those were fixed in 10% formaldehyde and later processed for paraffin embedding. Sections were obtained and stained by H.E for histopathology analysis. The degree of epithelial contraction was measured and mast cell concentration were also evaluated. RESULTS: The treated group showed higher mast cell concentrations (p<0.05) associated with increased contraction at day 7 and 14 respectively. CONCLUSION: Ointment containing 5% Brazilian pepper tree oil increases mast cell concentration and promotes skin wound contraction in rats.UFRPEUNIFESPUFMGUNESPUNES

    Relação entre aleitamento materno e hábitos de sucção não nutritivos

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    Este estudo objetivou identificar o tipo e o período de tempo de aleitamento recebido por crianças e verificar a associação com hábitos de sucção não nutritivos. Trata-se de um estudo transversal, retrospectivo, no qual foi aplicado um questionário em 330 mães ou responsáveis por crianças de 3 a 6 anos matriculadas em pré-escolas de Araçatuba (SP), após consentimento livre e esclarecido. Observou-se que 86,4% das mães amamentaram seus filhos. Quanto ao período de tempo, apenas 33,4% delas amamentaram exclusivamente no peito após seis meses de vida. O tempo médio de amamentação materna exclusiva recebida foi 3,84 meses e o de aleitamento complementar foi de 11,68 meses. Do total, 53,3% relataram que os filhos apresentavam hábitos de sucção não nutritivos, e destes 70,45% não foram amamentados exclusivamente no peito durante os seis primeiros meses de vida, existindo associação significativa entre os dois (pThis study sought to identify the type and duration of breastfeeding received by children and establish the association with non-nutritive suction habits. A retrospective, transversal study was conducted using a questionnaire given to 330 mothers or persons responsible for 3 to 6-year-old children registered in kindergartens in Araçatuba, State of São Paulo, after obtaining their free and informed consent. It was revealed that 86.4% of mothers breastfed their children. With respect to duration, only 33.4% of these mothers breastfed exclusively after 6 months. The average time of exclusive breastfeeding received by children was 3.84 months and complementary breastfeeding was 11.68 months. Of this total, 53.3% reported that their infants manifested non-nutritive suction habits and of these children, 70.45% were not exclusively breastfed for the first 6 months, there being a significant association between both (p<=0.05). Pacifier use was the most frequent habit (44.4%), showing a statistically significant association with breastfeeding time (p<0.0001). It was concluded that breastfeeding was practiced, albeit for a lesser duration than considered indispensable for the baby's development, there being an association between duration and type of breastfeeding and non-nutritive suction habits

    Plant species diversity for sustainable management of crop pests and diseases in agroecosystems: a review

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