Application of pulsed Nd:YAG laser in thin foil microwelding

Experimental investigations were carried out using a Nd:YAG laser operating in pulsed mode for welding a lap joint between thin foil and thick sheet. The pulse energy was varied from 1.5 to 3.0 J at increments of 0.25 J with a 4 ms pulse duration. The base material used for this study was AISI 316L foils with 100 mu m thickness and sheet with 3.0 mm thickness. The welds were analysed by optical and electronic microscopy, tensile shear tests and micro hardness. The results indicate that pulse energy control is of considerable importance to join thin foil and thick sheet with good quality. The ultimate tensile strength of the welded joints increased at first and then decreased as the pulse energy increased. The process appeared to be very sensitive to the gap between couples. Large voids delimited by the molten zone boundary were observed in joints welded with high pulse energy.

Identification of nonlinear structures using discrete-time Volterra series

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

Effects of laser beam energy on the pulsed Nd:YAG laser welding of thin sheet corrosion resistant materials

The aim of this study was to value the possibility to join, for pulsed Nd:YAG laser welding, thin foils lap joints for sealing components in corrosive environment. Experimental investigations were carried out using a pulsed neodymium: yttrium aluminum garnet laser weld to examine the influence of the pulse energy in the characteristics of the weld fillet. The pulse energy was varied from 1.0 to 2.5 J at increments of 0.25 J with a 4 ms pulse duration. The base materials used for this study were AISI 316L stainless steel and Ni-based alloys foils with 100 mu m thickness. The welds were analyzed by electronic and optical microscopy, tensile shear tests and micro hardness. The results indicate that pulse energy control is of considerable importance to thin foil weld quality because it can generate good mechanical properties and reduce discontinuities in weld joints. The ultimate tensile strength of the welded joints increased at first and then decreased as the pulse energy increased. In all the specimens, fracture occurred in the top foil heat-affected zone next to the fusion line. The microhardness was almost uniform across the parent metal, HAZ and weld metal. A slight increase in the fusion zone and heat-affected zone compared to those measured in the base metal was observed. This is related to the microstructural refinement in the fusion zone, induced by rapid cooling of the laser welding. The process appeared to be very sensitive to the gap between couples.

Determinação da resistência à flexão de ligas odontológicas, utilizadas em prótese parcial fixa e prótese sobre implante, soldadas por brasagem e a laser

Pós-graduação em Odontologia Restauradora - ICT

Degenerative joint disease in cattle and buffaloes in the Amazon region: a retrospective study

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

Instituições, confinamento e relações de poder: questões metodológicas no pensamento de Michel Foucault

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

Use of a type IIB external skeletal fixator in experimental tarsocrural arthrodesis in dogs

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

Incidência e Caracterização de Lesões Desportivas no Taekwondo segundo o Gênero

Taekwondo practice has been associated with physical and biomechanical overloads, which are related to occurrence of sports injuries (SI). However, etiological and nosographic information about SI are limited and conflicting. This study analyzed and characterized the SI in Taekwondo athletes, according to gender. Casuistic integrated 22 athletes, 12 men and 10 women, athletes from São Paulo State Team of Taekwondo, adult category, with 23,6±6,8 years, body weight of 66,0±13,1 kg and 1,72±0,09 m of height. Reported morbidity survey was used to obtain retroactive information to 2009 season. Nosographic variables were analyzed using Goodman’s Test for contrasts among multinomial populations. All athletes reported injuries in the season; 56 cases were registered, determining an injury rate of 2.54 SI/athlete; 26 events (46.4%) occurred in males (2.17 SI/athlete), and 30 (53.6%) were related to women (3.00 SI/athlete). There were predominance of injuries in joints (35,7%) and muscles (39,3%); both genders presented injuries in lower members (82.1%, p<0.01), predominant in combat situations (80.4%, p<0.05), during the preparatory period of training (73.2%). There was a higher treatment request among male athletes (73.1%), which showed high asymptomatic return (69.2%); the female group referred similar proportions of absence and presence of treatment request, collaborating for the greater symptomatic return of these athletes (70.0%). In conclusion, the results support predominance of muscles and joints injuries in lower segments, derived from fighting, involving female athletes.

Experiências de estágio curricular supervisionado e portfólios de aprendizagem

This article portrays Supervised Curricular Training experiences in Paulistas Universities by means of learning portfolios. The reflections presented indicate the pathways of experiences with this feature didactic-pedagogical motivator of qualitative advances in cultural formation of students and teachers of the Pedagogy Course. The methodological approach was chosen for consistent in the defense of necessary joints of dialogical, reflexive and emancipatory dimensions in training teachers for Early Childhood Education, and to contribute in the mediation of the activities carried out by undergraduates, with individualized follow in the formation of each one of them. The experience, stand out learnings regarding limits of this practice and the significant advances realized in each student, by means of their written work, sharing of knowledge, the interlocution between them and the teachers and the link with theory and practice through the Internship Supervised and the use of learning portfolios.

Preparação e caracterização estrutural, mecânica e anelástica de ligas do sistema Ti-Ta contendo oxigênio intersticial, para uso biomédico

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise da falha do suporte de mancal de um eixo cardan utilizado num veículo pesado

Pós-graduação em Engenharia Mecânica - FEG

O Método de Kane aplicado a um modelo de corpo humano para obtenção da pressão intradiscal na coluna lombar

Nos últimos anos tem surgido vários métodos para se estudar sistemas multicorpos. A vantagem destes métodos é a obtenção das equações do movimento de forma mais fácil e precisa. Robôs, manipuladores, mecanismos, satélites, máquinas em geral e sistemas biomcânicos, pelas suas características, podem ser vantajosamente tratados por formalismo multicorpo, mas precisamente, o método de Kane a um modelo do corpo humano, com a finalidade de se determinar a pressão intradiscal entre as vértebras L4/L5 da coluna lombar, em algumas atividades normais de vida diária, como: sentar, abaixar, pegar e elevar cargas, realizar movimentos de flexão e extensão. Pretendeu-se, também obter os esforços internos nas diversas articulações deste modelo. A pressão intradiscal representa um parâmetro importante para caracterizar a sobrecarga na coluna, podendo ter relação com a degeneração do disco intervertebral, o que produz muita dor em indivíduos. Inicialmente, o modelo foi proposto e o método de Kane foi aplicado para se obter as equações do movimento. Para resolvê-las, foi necessário realiza a filmagem de um sujeito realizando as atividades citadas, a fim de se obter as equações das trajetórias dos diversos segmentos do corpo humano. Após a simulação, os parâmetros desejados foram obtidos e comparados com valores experimentais citados na literatura.

Can cone-beam computed tomography superimposition help orthodontists better understand relapse in surgical patients?

This case report describes the interdisciplinary treatment of a 19-year-old Brazilian man with a Class I malocclusion, a hyperdivergent profile, an anterior open bite, and signs of temporomandibular joint internal derangement. The treatment plan included evaluation with a temporomandibular joint specialist and a rheumatologist, orthodontic appliances, and maxillomandibular surgical advancement with counterclockwise rotation. Cone-beam computed tomography images were taken before and after surgery at different times and superimposed at the cranial base to assess the changes after orthognathic surgery and to monitor quantitatively the internal derangement of the temporomandibular joints and surgical relapse. Our protocol can improve the orthodontist's understanding of surgical instability, demonstrate the clinical value of cone-beam computed tomography analysis beyond the multiplanar reconstruction, and guide patient management for the best outcome possible.

Goniometric evaluation of both forelimbs and hind limbs in two species of Neotropical monkeys

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