272 resultados para Complexidade estrutural


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This study was accomplished in existing Cerrado's relicts at State Park Guartelá, Tibagi, PR (24°39'10S and 50°15'25W), which represent one of the last extreme-meridional remanescents of this type of formation. Fifty plots with dimensions of 5x5m were allocated for phyto-sociological analysis, including in the sample individuals with height ≥ 1 m, divided into two samples to evaluate the following strata: a) upper-plants with DAS ≥ 3 cm, and b) intermediate - plants with DAS <3cm. Moreover, in each plot, there were established sub-plots with dimensions of 1x1m for sampling the lower stratum, comprised by individuals with height <1m and >10cm. The complete survey found 1340 individuals distributed in 28 families, 66 genera and 115 species. The diversity index was higher for the mean component (H'=3.30), followed by the superior component (H'=3.09) and the inferior (H'=2.91). The frequent occurrence of bushes is a remarkable characteristic of the physiognomy of the areas inside the park and 82 % of the populations studied are distributed in aggregated standard. Because it is a marginal region of occurrence of cerrado vegetation, now under the influence of a subtropical climate, more humid and cold, compared to the core area of this biome, it is noted that these areas are characterized by a decrease in stature, richness and diversity of its flora. Nevertheless, they preserve typical species of the Brazilian Savannah; but, due to their distribution in relicts and been, in part, devastated, some are included in the red list of endangered plants in Parana state, which evidences the importance of conservation and management of these areas.

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A utilização de pistas hápticas para a estabilização da postura através do toque vem sendo apontada como uma eficiente fonte de informação sensorial que conecta o indivíduo ao meio. Dessa forma, o paradigma do toque leve (i.e., tocar uma superfície com força inferior a 1 Newton) é uma das possibilidades de, através do contato com determinada superfície, atenuar as oscilações do indivíduo. Sendo assim, o objetivo deste estudo foi verificar a eficiência do toque leve em tarefas de alta complexidade ao equilíbrio e, concomitantemente, analisar a relação entre percepção háptica e controle da postura. Para isso, 15 adultos jovens saudáveis participaram deste estudo, permanecendo em pé na posição tandem sobre uma plataforma de força e-nas condições pertinentes-sobre uma trave de equilíbrio. As condições deste estudo variaram entre a utilização ou não do toque, a utilização ou não da visão, e ainda, permanecer em pé sobre uma superfície de altura normal (0 cm) ou uma superfície com elevação (20 cm). Através da análise estatística avaliamos as variáveis amplitude média de oscilação (ântero-posterior e mediolateral), velocidade média (ântero-posterior e medio-lateral) e a trajetória total. Nossos resultados demonstraram, como já era esperado, um aumento significativo da oscilação corporal nas condições sem toque e sem a utilização da visão, e ainda maior quando houve elevação da superfície de apoio dos pés. Entretanto, quando o toque leve foi utilizado nessas mesmas condições houve uma redução significativa da oscilação postural dos indivíduos. Dessa forma, concluímos que mesmo em tarefas de alta instabilidade ao equilíbrio, o toque leve continua auxiliando no controle da postura

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The sol-gel process is a method for obtaining vitreous or vitro-ceramic materials which, are prepared a sol and by drying the liquid phase. This technique has been used extensively for the preparation of glassy gels, films, fibers and particles from the hydrolysis and polycondensation reactions of metal alkoxides. The usual methods for drying are: evaporation drying (xerogels), freeze drying (criogéis) and via supercritical CO2 extraction (aerogels). In the present work, we studied the preparation of silica gels by the sol-gel process from the hydrolysis of alkoxides tetraethylorthosilicate (TEOS) and 3-glycidoxypropyltrimethoxysilane (GPTS). The hydrolysis was promoted from GPTS and TEOS in proportion (4: 1) under acidic conditions. The hydrolysis reaction was promoted inside a Becker at room temperature. After hydrolyses the prepared sol had pH 2, and kept under mechanical agitation for a period of 1 hour. In order to accelerate the polycondensation reaction, the pH was corrected to a value near 5 by slowly adding NH4OH. Then the sols were leaked in sealed polycarbonate containers and maintained for 20 days at 40°C for gelation. Silica aerogels were prepared via supercritical CO2 extraction of the wet gel at temperature and pressure higher than 31°C and 74 atm, in an autoclave specially developed for the process. The structural characteristics were studied in the dry gel (aerogel). Aerogels were then characterized by nitrogen adsorption and small angle light scattering. The nitrogen adsorption data were analyzed for the determination of the BET specific surface (SBET), the total pore volume Vp, the pore mean size (lP=4Vp/SBET), the particle mean size (lS) and the pore size distribution (PSD). And the data from small angle light scattering were analyzed to determine the correlation function (γ'), the area per unit volume (S/V), average pore size (l ) and the average particle size...

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Pós-graduação em Economia - FCLAR

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Engenharia Mecânica - FEG

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Pós-graduação em Engenharia Mecânica - FEB

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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The expressive possibilities within the field of surface design come up with increasingly larger with the emergence of technologies that allow the construction of forms and structures of high complexity such as three-dimensional printing. Establishing a relationship between design and complex systems, this work seeks to address the significant interrelationship of new paradigms of science, designed from concepts such as chaos, complexity and self-organization along with the cyber and parametric design, assuming thus the consequent impact of these in the creation and construction of process surfaces. Starting from the investigation of the applicability of the aforementioned conceptual bases, will be exemplified prospects of surface, produced in the first instance through computer interfaces, assigning the emergence of new creative processes and technology. Furthermore, elucidating biomimetics and its importance in the design of the design as a means of inspiration in complex systems of nature.

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Pós-graduação em Agronomia (Produção Vegetal) - FCAV

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Química - IQ