Análise eletromiográfica dos músculos vasto medial e vasto lateral durante contrações isométricas de extensão do joelho

O joelho, por suas características anatômicas e freqüente instabilidade e exposição as lesões tem o quadríceps como importante músculo a ser desenvolvido quanto ao seu trofismo e força. Composto de quatro porções distintas estas podem gerar diferentes vetores de força que podem ter relações diretas com o recrutamento de unidades motoras. O posicionamento articular, a conseqüente modificação do comprimento muscular e a intensidade da contração podem influenciar o desenvolvimento da força do quadríceps. Dentre as contrações relacionadas ao maior recrutamento de unidades motoras com o intuito do desenvolvimento de força está a contração isométrica. Dentre as contrações musculares, as isométricas têm sido frequentemente indicadas para aumentar a força e estabilidade articular em sessões de treinamento e reabilitação. Pelo exposto, o objetivo do estudo foi analisar os músculos vasto medial (VM) e vasto lateral (VL) por meio da eletromiografia de superfície durante 15s de contração isométrica a 20%, 30%, 40% e 50% da contração isométrica voluntária máxima – CIVM com o joelho a 90 graus. Foram utilizados eletrodos de superfície bipolar de Ag/AgCl, posicionados nos músculos VM e VL, um módulo de aquisição de sinais biológicos (Lynx) calibrado com ganho de 1000vezes, filtro de passa alta de 20Hz e de passa baixa de 500Hz. Uma célula de carga foi acoplada perpendicularmente à cadeira de teste especialmente desenvolvida para o estudo e utilizado uma indicador digital para retorno visual. Na análise estatística utilizou-se teste de Friedman e teste de Wilcoxon, e adotou-se nível de significância de p<0,05. Verificou-se que os músculos VM e VL foram semelhantes entre si, e entre as cargas, houve diferença significante entre as cargas de 20% e 40%, 20% e 50%, e 30% e 50% para ambos os músculos, com maior atividade nas cargas de 40% e 50% CVM... (Resumo completo, clicar acesso eletrônico abaixo)

Análise teórica e experimental de uma ventaneira de alto forno, visando seu comportamento térmico e fluidodinâmico

In this work, it was studied the thermal and fluid dynamic behavior from theorical and experimental point of view of a blast furnace tuyere. The tuyere is responsible for the hot air insuflation into the blast furnace. The parameter used in the comparison was the difference between the cooling water inlet and outlet temperatures. There were used forced convection correlations inside circular sections with adequations for non circular sections. Based on operations dates of flux and thermal loads it was possible to model numerically the tuyere, and, since it was obtained the wall temperatures, estimate the conduction and convection resistances and the heat flux through the walls in contact with the water. The total heat fluxes from wall to water were applied to the energy conservation equation where could be estimated the theorical temperature variation. Compared to the real value, the theorical value presented a difference of 0,2 °C. Considering that the boundary conditions around the tuyere are transitories and that your channels have some rugosity irregularities we can consider the estimation method for cooling system coherent with the real operational parameters

Estudo de placas elásticas pelo metodo dos elementos de contorno

Este trabajo tiene como objetivo principal oferecer una herramienta alternativa para la resolución de placas finas, presentes en edifícios, relacionadas con los métodos de cálculo adquiridos durante la universidad, calculo a través de tablas con pocas condiciones de controno. El método utilizado es el Método de los elementos de contorno que discretiza la placa en partes finitas, aproximando los resultados obtenidos a valores reales. En este trabajo se ha utilizado el programa de ordenador Placas2.for (TAGUTI,Y. 2010) basado en el Método de los elementos de contorno para la resolución de las placas finas con varias condiciones de contorno geométricas y de cargas

Alterações microestruturais decorrentes dos sucessivos reparos de solda TIG aplicados ao longo da vida útil de uma estrutura aeronáutica crítica à segurança de vôo

The steel type AISI 4130 (ultra-high strength steel) is an alloy of low carbon and its main alloying elements are chromium and molybdenum, which improves the toughness of the weld metal. It has numerous applications, especially where the need for high mechanical strength. It is widely used in equipment used by the aviation industry, such as cradle-tomotor, and this is the motivation for this study. Cots are of fundamental importance, because the engine supports and maintains balance in the fixed landing gear. This equipment is subjected to intense loading cycles, whose fractures caused by fatigue are constantly observed. Will be determined the effects caused by re-welding the structure of aeronautical equipment, and will also study the microstructure of the metal without welding. The studies will be done on materials used in aircraft, which was given to study. The results provide knowledge of microstructure to evaluate any type of fracture that maybe caused by fatigue. Fatigue is a major cause of aircraft accidents and incidents occurred, which makes the study of the microstructure of the metal, weld and re-solder the knowledge essential to the life of the material. The prevention and control of the process of fatigue in aircraft are critical, since the components are subjected to greater responsibility cyclic loading

Fabricação de rodas: uma análise comparativa

In our country, the majority of freight and people by road happens municipal, state and federal. Thus, the heavy vehicles like buses and trucks are the main means of transporting people and cargo. This graduate work aims to study the process of manufacturing wheels for trucks, because we can see the lack of literature on the manufacturing process of wheels and also the importance of the processes used to manufacture wheels, such as lamination, stamping, puckering, machining, welding and painting

Bancos de capacitores se corrente de Inrush

This work discusses about the effects and methods of control and elimination of the currents transients generated by switching capacitor banks, this currents are called inrush currents. Capacitor banks are widely used to compensate a low power factor generated by the widespread use of inductive loads. Currently many of these banks are automatic and therefore the capacitive cells are connected and disconnected according to the inductive loads on the network. However when connecting a capacitor bank to a bus can generate currents transients generated by electromagnetic transients. Aspects of the network, for example, the existence of a bank already connected to the bus, can influence the intensity of this phenomenon. This paper discusses some characteristics of the capacitors and the network to justify and explain the appearance of these transients and discusses its effects on the network and to other equipment. It is concluded that the main cause of this phenomenon is the voltage difference between the capacitor to be connected to the network and the bus, the results of the study were the bases to discuss the traditional methods to mitigate these currents and therefore its negative effects. Although in this paper is yet developed a method of electronic switching that can greatly reduce these transients

Smart Grid e Carros Elétricos - Influência da Carga de Carros Elétricos Sobre o Sistema Elétrico

The technologies are advancing at a pace so expressive that allow the increase of the power quality from generation until the distribution to end customers. This improvement has been made possible through the automation of the energy that follows to a better quality of the energy provided, a lower energy supply disruptions and a very short recovery time. The trend of today and the near future is the distributed energy generation. To keep the automated control of the chain, the presence of Smart Grids is needed and that will be the most efficient and economical way to manage the entire system. Within this theme, is going to be necessary analyze the electric cars that promise to promote a more sustainable transport because it doesn’t uses fossil fuels, and more healthy because it does not emit pollutants into the atmosphere. The popularization of this type of vehicle is estimated to happen in a few decades and the case study analyzing its influence on the demand of the electrical system is something that will be very important in the near future. This paper presents a study of the influence of the inclusion of charges refering to electric cars

Estudo de capacidade de armazenagem e frota em uma empresadoramo de bebidas

This paper presents a case study in a largebeverage company,which suffers fromlack of inputs. Through 5 Whys analysis,it was possible to find the root causes of the problem: the bad fleet sizing deliveriesand low capacityof storage of inputs. Through the use of simulation, it was possible to determine theactual fleet required, and it was alsoquantified thespace required for thestorage ofloads.Based on these results andconsidering the cost, it waspossible todetermine which the most effective solutions toreducing the initialproblem: the increase of storage capacity, considered the best option, even demanding time, or the increase of the fleet, considered a stopgap measure to partially solve the problem until the first solution is finalized

Efeito do exercício prévio na determinação da potência crítica

The objective of this study was to analyze the influence of previous exercise on the determination of critical power (CP). Seven apparently healthy nontrained males, of 18 to 25 years, participated of this study. The subjects were submitted, in different days to the following protocols in a cyclergometer: 1) one progressive test until voluntary exhaustion for the determination of lactate threshold (LL), maximal oxygen uptake (VO2max) and its corresponding intensity (IVO2max); 2) six constant workload tests at 95,100 and 110% IVO2max until exhaustion with and without a previous exercise at 70% , in random order. The exhaustion times (tlim) at 95, 100 and 110% IVO2max were adjusted forme thress models of two parameters to estimate CP and anaerobic work capacity (AWC) [P=CTAn/tlim)+CP; tlim = CTAn/(P-PC); P=PC.tlim+ CTAn]. The model with the lowest standard error was considered for the estimation of CP. The tlim at 95% IVO2max was similar without (501 ± 140 s) and with previous exercise (473 ± 99 s). However, the tlim at 100% (381 ± 103 s and 334 ± 101 s) and 110% IVO2max (267 ± 163 s and 227 ± 68 s) was significantly longer with previous exercise. There was no significant difference in CP and AWCat conditions without (200 ± 27 W and 23 ± 11 kJ, respectively) and with previous exercise (212 ± 30 W and 18 ± 8 kJ, respectively). It can be concluded that the parameters of the relationship between power and time were not modified by the previous severe exercise

Projeto, desenvolvimento e construção de um redutor/multiplicador de velocidades de baixo custo

This paper aims to present the design, development and construction of a reducer / multiplier speeds low cost, sturdy and easy operation. The beginning of the project was given to research on issues related to mechanisms and machine elements, and these theories of fundamental importance in the development of items of equipment which, together with the aid of AutoCAD software, enabled the construction of it. Parallel to the sizing of equipment, were also investigated and taken into account the costs of materials used in the project. Made to mount the reducer / multiplier speeds it was at the evidence through experiments involving the use of torque wrench, tachometer and weights, getting proven applicability in situations that are small or medium loads required

Centro de educação, cultura e lazer

O presente Trabalho Final de Graduação apresenta um projeto que se baseou no programa oferecido pelo Centro Educacional Unificado – CEU, equipamento público criado em 2001 pela Secretaria Municipal de Educação da Prefeitura de São Paulo destinado a áreas periféricas da cidade de São Paulo. E também no programa oferecido pelo SESI – Serviço Social da Indústria, entidade de direito privado criado em 1946 pela CNI – Confederação Nacional da Indústria. Formulado para funcionar como um espaço de sociabilização da vida urbana e com o intuito de oferecer EDUCAÇÃO, CULTURA E LAZER para o desenvolvimento integral de crianças, jovens e adultos das comunidades do entorno. O programa desenvolvido para o CENTRO DE EDUCAÇÃO, CULTURA E LAZER, conta com um Bloco Cultural o qual apresenta espaços como: Biblioteca, Teatro, Refeitório, Administração, Salas de atividades diversas e a Creche; o Bloco Educacional Abriga um Centro de Educação Infantil (CEI), uma Escola Municipal de Educação Infantil (EMEI), uma Escola Municipal de Ensino Fundamental (EMEF) e Educação de Jovens e Adultos (EJA). E por fim, uma Praça de Esporte e Lazer equipada com Ginásio Poliesportivo coberto, quadras descobertas, piscinas e playground, sendo estes espaços abertos aos finais de semana com a finalidade de proporcionar opções de recreação em beneficio de toda comunidade. A escolha do local para a implantação deste projeto foi a cidade de Ribeirão Preto (localizada a nordeste do Estado de São Paulo), no bairro Jardim Jamil Seme Cury, conjunto habitacional criado para receber moradores vindos de uma comunidade carente que se localizava no entorno do aeroporto Leite Lopes, o qual passa por discussões para a inserção de um Terminal Internacional de Cargas, e consequentemente necessita ampliar sua área de abrangência

Validação dos parâmetros aeróbio e anaeróbio a partir de protocolo não invasivo aplicado ao exercício resistido - supino reto

The purpose of this study was to investigate the validity of critical force test from maximal lactate steady state (MLSS) during resistance test using straight bench press. Five healthy male volunteers aged (22.6 ± 2.88 years), weight (76.3 ± 11.49 kg) e height (182.6 ± 7.54cm), trained in resistance exercise, and performed four diferent test to determine: one maximal effort (1RM), critical force using the critical power model (force vs 1/time limit - 20, 25 and 30% 1RM). The CF was the linear coefficient and the anaerobic impulse capacity (CIA) was the angular. MLSS was determined using loads of 80, 90, 100 and 110% of critical force. Blood lactate samples were abtained at each 300sec between each stage of total 1200sec. Maximal 30s test (M30) was accomplished with load of 25% of body weight in SBP. The results showed that the 1 RM was 79.4 Kgf (± 16.98), CF 10.1N (± 2.25), CIA 1756.82 N.s (± 546.96) and the R² 0.984 (± 0,02). The MLSS occurs at 100% CF load. The lactate concentration at the MLSS was 2.2 mmol/L (± 0.77). Significant correlation was observed between MLSS and CF on SBP (r = 0.88 p = 0.05). In M30 the minimum, mean and peak power were (25.0 ± 4.9, 28.0 ± 4.9, and 30.0 ± 4.6 kgf.rps, respectively). The fatigue index was 18.0% (± 6,8). The M30 was significantly correlated with Ppeak and Pmean (r = 0.98 for both, p = 0.003). The CF means has been validated to predict the resistance training and the CIA show to be a representative anaerobic parameter in straight bench press.

Avaliação da auto-suficiência energética de reatores anaeróbios no tratamento de esgoto sanitário e de água preta

The purpose of this project is to verify whether anaerobic reactors applied to sewage treatment are energetically self-sufficient. This evaluation can be made by balancing the methane produced through the anaerobic transformation stages (hydrolysis, acidogenesis, acetogenesis and methanogenesis) and the reactor energy consumption requirements. The original project included methanogenic activity tests, which could not be performed due to setbacks in the installation of an analytical instrument. Scientific articles about bench- and full-scale anaerobic reactors were investigated instead. An average substrate-to-methane conversion efficiency of 58,2±18,6% was found for the bench-scale reactors and higher efficiencies (89,2%) were found for the cases which had higher Organic Loading Rates (OLRs) values. The average energy output was 0,013 kWh/Lsewage, value unable to meet the energy needs for the reactor operation, considering equipments normally used such as temperature controller. This balance can become positive if few hypotheses are made, for example (i) to eliminate the use of temperature controller (ii) to alter the operation pattern from continuous to intermittent. Based on energy balance assessment of eight bench-scale reactors, it was observed that the implementation of a system for biogas utilization is not energetically feasible. However, interesting results were found for a full-scale sewage treatment plant, ETE Ouro Verde – Foz do Iguaçu, PR, Brazil. Even though its substrate-tomethane conversion efficiency was about 10% only, the energy balance was quite positive, with energy consumption of 68 kWh/month and energy production of 660 kWh/month. This analysis leads us to conclude that energy recovery from full-scale sewage treatment plants should be practiced by other plants

Intervenção urbana: transporte público e qualidade de vida na cidade sem limites - terminal urbano central de Bauru

O grau de desenvolvimento econômico e social de uma sociedade pode ser avaliado diretamente à facilidade de transporte de passageiros e cargas. A qualidade de vida nas cidades é fortemente influenciada pelas características do transporte público. O Brasil tem 80 % de sua população morando em cidades, de forma que uma maior utilização do transporte público seria a solução para problemas de congestionamento, poluição, acidentes, desumanização e outros males que atingem as cidades modernas. Bauru, interior de São Paulo, é uma cidade de porte médio que apresenta um dos maiores índices de utilização de automóveis particulares, em parte pela formação da cidade, que é “espalhada”, e outra por suas características econômicas. A população de baixa renda, moradores da periferia e dependentes do transporte público, enfrenta grandes dificuldades para acessar as diferentes áreas da cidade (má operacionalização do sistema?). Este trabalho de finalização da graduação tem como objetivo maior trazer opções e facilitar o acesso da população a todas as áreas da cidade, através de um sistema de terminais e mini-terminais urbanos de transporte coletivo, buscando a melhor utilização do espaço público, uma maior mobilidade na cidade e a melhoria da qualidade de vida da população

Estudo de uma ponte rolante comercial no transportede bobina de aço de 12 toneladas

This work aims to determine the stresses acting on the main beam of a crane to transport steel coils of up to twelve tons. To determine the stress it was made a revision of the knowledge of the mechanics of materials to apply the analytical method. Following a review of the finite element method is made to understand the same. To complete the study it was used the commercial software ANSYS to determine the stresses by finite element method, the program provides images that help to better understand the results obtained. With the results a comparison of the values of the tensions between the two methods (analytical and finite element) was made. To assist in the calculations it was used the NBR 8400, 1984 (Calculation of Lifting Equipment Load)