Metodologia de determinação das curvas de probabilidade de falha S-N-P para uma liga de aluminio submetida a diferentes tratamentos termicos de solubilização e precipitação

The approach of the subject matter in this work relies on the fact that the reliability of methods for performance analysis of materials proves critical for the result. This work focused on the development and presentation of the methodology for lifting probability curves for fatigue test (SN) according to standard E739, this focus is justified by the fact that the results in fatigue test show considerable dispersion making it difficult to reading and interpretation of data, this dispersion arises because the phenomenon of rupture is strongly influenced by internal characteristics of the material, we can then have much data ranging from test to test. Thus we set out originally for a brief study of aluminum alloys in question, as well as the treatments to which they were subjected. We also studied the behavior of materials when subjected to cyclic loading, which configures process of fatigue failure, and even fatigue test method in question. This statistical analysis is based on the ASTM E739 standard, so its contents was studied in detail so that we could present in detail the methodology and raise SN curves for different aluminum alloy 7012 subjected to fatigue test. Data were collected from tests conducted in the department of materials from two samples of aluminum alloy 7012 solubilized and precipitated by different time intervals and assayed temperature fatigue-type traction-compression, these data were then analyzed and used to survey curves using the base as E739. After lifting the curve analyzed the characteristics of the test samples and their correlation with the test results. We confirmed the effectiveness of the method of statistical analysis by ASME E739, which allowed the reading of data without this method would be very difficult to have a reading and comparison of the results for the two types... (Complete abstract click electronic access below)

Proposta de um dispositivo para ajuste automático da altura de uma cama hospitalar

This paper proposes a mechanical device to adapt a simple model of hospital bed used in the Emergency Department at Santa Casa of Guaratinguetá, allowing the bed’s height adjustment with electromechanical drive. This adaptation aims to introduce improvements in the routine work of nurses and reduce ergonomic problems stemming from repetitive strain during the transfer of patients to stretchers and wheelchairs, as well as providing more comfort to the bedridden patient. The device is mainly composed of: an electric induction motor used to drive the engine, a steel spindle with square thread, which allows axial displacement of the bed, a transmission system with pulleys and belt, which transmits power supplied by the motor to the spindle. The mechanism allows the height of the bed is regulated between 400 and 800 mm. The estimated implementation cost of this proposal is lower than the acquisition cost of a commercial hospital bed with the same features, which confirms the feasibility of the proposed solution

Proposta de um dispositivo para adaptação em uma cama hospitalar para ajuste de altura

In hospitals, health professionals may face different situations and problems. By following them, it is remarkable that one of the difficulties is related to the support provided by the facilities to carry out their work. This also affects the quality of treatment offered to patients. One of the points of improvement that could be studied is hospital beds. The Fawler's simplest hospital bed type, used in most Brazilian public hospitals, is designed with an ergonomic average height that offers a default position for analysis and treatment of patients. There is no possibility of adjusting the height of those beds, and hence there is a limitation in this regard since that height is fixed, but the physical structures of the workers and patients may vary widely and there may be a conflict when there are people too large or small involved in this process. Beyond that, studies by experts show that beds with height adjustment decreases the muscular effort and improve the movement quality of the spine of nursing staff, reducing the force on certain vertebrae and also the ergonomic risk. Of course, patient comfort is also affected accordingly. As the beds made with height adjustment are very expensive, this study aims to design a device to adapt the not adjustable beds. The project must be viable from an economic and mechanic standpoint, being able to adapt both old and new simplest Fawler hospital bed models, since their dimensions are similar. The final result shows that it is possible to adapt such beds using the designed concept at a viable cost. Furthermore, this concept could be applied in other bed types or objects that have hollow feet

Uma ferramenta para o estudo local de curvas e superfícies singulares no espaço Euclidiano

O objetivo deste trabalho é aplicar uma clássica ferramenta da Teoria de Singularidades, a saber, desdobramentos de funç˜oes reais, no estudo da estrutura local de alguns subconjuntos do espaço Euclidiano.

Avaliação da resistência ao cisalhamento de um solo tropical não saturado

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

Ajuste metabólico e respostas imunes de pacus juvenis alimentados com diferentes níveis de carboidratos e submetidos a jejum prolongado

Pós-graduação em Zootecnia - FCAV

Comportamento das curvas de saturação da água e LNAPL em solo da formação Rio Claro

Pós-graduação em Geociências e Meio Ambiente - IGCE

Morphometric growth characteristics and body composition of bullfrog tadpoles in captivity

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

Deposition of bodily chemical components in the carcass of tilapia (oreochromis sp.) strains

The knowledge of how animals deposited chemical components as water, protein, fat and ash in the carcass is importance for the formulation of a balanced diet, allowing maximum performance with a low environmental impact. So, the study was carried out to evaluate the influence of different tilapia strains (Chitralada, Commercial, Red and Universidade Federal de Lavras [UFLA]) on the deposition of bodily chemical components in the carcass. The bodily components analyzed were water, protein, fat and ash. For the determination of the bodily chemical deposition curves by age, the exponential, Brody, logistic, Gompertz and von Bertalanffy models were adjusted. The Commercial and UFLA strains deposited water at a faster speed (P<0.05) compared with the remaining strains. As for protein, the Red strain had a lower estimated maturity weight (49.37 g), and was more precocious (202 days) with regard to maximum deposition in comparison to the other strains (Chitralada, UFLA and Commercial) in which there was an estimated maturity weight of 231.5 g and maximum depositionfor 337 days. There were no differences (P>0.05) for the logistic model parameter between Red, UFLA and Commercial strains for fat, which presented a maximum fat deposition (0.23 g) at 310 days of age. Regarding ash deposition, the Commercial strain presented a higher maximum deposition (0.10 g) at 337 days, occurring later than the other strains that presented maximum deposition (0.033g) at 254 days of age. Thus, it was concluded that the genetic strains evaluated differ in chemical deposition curves of water, protein, fat and ash.

Estudo do efeito do transporte de massa nas curvas de polarização potenciodinâmica em ligas de alumínio da série 7XXX de aplicação aeronáutica

Aluminum Alloys are widely used as structural materials in the aerospace industry due to low weight, high mechanical strength and enduring corrosion resistance. Their resistance to corrosion is attributed to the rapidly formed stable oxide film (Al2O3) which spontaneously forms itself on the surface of the material. However, in the presence of aggressive ions, such as halide, Aluminum Alloys are subject to a localized process of corrosion. The electrochemical behavior of 7081-T73511 and 7050-T7451 Aluminum Alloys employed in the aerospace industry was investigated using a 0.6 M NaCl solution under the conditions of a controlled mass transport employing a rotating disk electrode. The theoretical limiting current density was determined by the Kouteki-Levich equation. The results confirmed that the inter-metallic Al7Cu2Fe acts as preferential cathode generating the galvanic coupling and the dissolution of the Aluminummatrix around it.

Número de Milnor associado a curvas reduzidas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Seleção genômica para características longitudinais de bovinos da raça Holandesa

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Controle visual de automóveis em curvas em situação simulada: efeitos da experiência em contexto real

Dirigir é uma tarefa altamente complexa que requer sincronia entre informações adquiridas e comandos motores, sendo a visão fonte primordial de recursos para o controle do volante por parte do motorista, para que este possa fazer a manobra na quantidade correta e no momento apropriado. Simulações nem sempre preservam os aspectos relevantes do ambiente. O ponto tangente (PT), local mais interno da curva, é onde os motoristas olham em situações de curva ao conduzir um veículo durante contexto natural, e, de acordo com a literatura, este fenômeno também ocorre em situações experimentais com o uso de simuladores específicos de trânsito. Este estudo visa verificar se este comportamento se reproduz em situação simulada de videogame e como a experiência de dirigir naturalmente afeta o desempenho na simulação. Foram recrutados vinte participantes, divididos em dois grupos de dez pessoas cada, com e sem Carteira Nacional de Habilitação e todos com experiência em videogame. A tarefa foi conduzir um veículo em circuito gerado por um jogo de videogame, enquanto seus olhos, e seus respectivos movimentos, foram monitorados e gravados por sistema eye-tracker. Para análise dos dados, foi utilizado o vídeo da imagem gerada pelo videogame com a adição do cursor referente ao olhar do participante. Foram analisadas apenas as situações nas quais os participantes executavam a manobra de cada uma das onze curvas do percurso, utilizando o software ASL Results Plus (versão 1.8.2.18) para estabelecer Áreas de Interesse (AI) de 3º e 10º ao redor do ponto tangente da curva. As variáveis dependentes foram Número Total de Fixações (NF) e Duração Total das Fixações (DF). Os dados foram submetidos à análise de variância de medidas repetidas, tendo fatores grupo (HA ou NH), AI (outros 3º ou 10º) e curvas (onze curvas). Não houve efeito significativo de grupo para ambas as variáveis dependentes. Houve efeito principal de...