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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Development of a Tow Capacity Test Device for Small Unmanned Vehicles

Barnett, Shane 24 January 2006 (has links)
Unmanned ground vehicles (UGVs) will increasingly be used for tasks such as retrieving injured soldiers from a battlefield, transporting supplies, and towing other small vehicles and payloads. To date, the unmanned test community has not standardized on an apparatus or test operating procedure (TOP) specifically for evaluating the towing capacity of small unmanned ground vehicles. Draw-bar testing has been adapted by several groups to quantify small unmanned ground vehicle (SUGV) tow capacity; however, these devices are inherently limited to measuring peak static towing force. This paper describes an alternative method using a variable-resistance tow sled for quantifying the dynamic towing capacity of SUGVs. The tow sled contains a frontal skid plate and a rear axle and wheel arrangement. A weighted carriage is transferred from the rear of the sled to the front of the sled by a cable geared to the rear axle. As the sled is pulled along the ground, towing resistance increases in a controlled linear fashion. An encoder on the rear axle and a load cell in the tow chain provide motion and force data. Testing of the tow sled has been conducted on a TALON SUGV at the Southwest Research Institute (SwRI) Small Robot Test Facility and a MATILDA SUGV at the Joint Unmanned Systems Test, Experimentation, and Research (JOUSTER) site. / Master of Science
62

Understanding the challenges in HEV 5-cycle fuel economy calculations based on dynamometer test data

Meyer, Mark J. 15 December 2011 (has links)
EPA testing methods for calculation of fuel economy label ratings, which were revised beginning in 2008, use equations that weight the contributions of fuel consumption results from multiple dynamometer tests to synthesize city and highway estimates that reflect average U.S. driving patterns. The equations incorporate effects with varying weightings into the final fuel consumption, which are explained in this thesis paper, including illustrations from testing. Some of the test results used in the computation come from individual phases within the certification driving cycles. This methodology causes additional complexities for hybrid electric vehicles, because although they are required to have charge-balanced batteries over the course of a full drive cycle, they may have net charge or discharge within the individual phases. The fundamentals of studying battery charge-balance are discussed in this paper, followed by a detailed investigation of the implications of per-phase charge correction that was undertaken through testing of a 2010 Toyota Prius at Argonne National Laboratory's vehicle dynamometer test facility. Using the charge-correction curves obtained through testing shows that phase fuel economy can be significantly skewed by natural charge imbalance, although the end effect on the fuel economy label is not as large. Finally, the characteristics of the current 5-cycle fuel economy testing method are compared to previous methods through a vehicle simulation study which shows that the magnitude of impact from mass and aerodynamic parameters vary between labeling methods and vehicle types. / Master of Science
63

Normativa styrkevärden i höftadduktorer och -abduktorer hos damfotbollsspelare på elitnivå

Karlsson, Lynn January 2021 (has links)
Inledning: Muskelstyrka i höftregionen är en viktig fysisk färdighet inom fotboll dels ur ett prestationsperspektiv, dels för skadeprevention. Trots detta saknas normativa isometriska styrkevärden för höftadduktorer och - abduktorer hos damfotbollsspelare. Syfte: Syftet med denna tvärsnittsstudie var att undersöka den isometriska höftstyrkan i adduktion, unilateralt och bilateralt, samt höftabduktion unilateralt med en handhållen dynamometer hos skadefria damfotbollsspelare. Metod: 29 friska damfotbollsspelare på elitnivå inkluderades i studien. Den isometriska höftstyrkan mättes vid ett tillfälle på försäsongen med en handhållen dynamometer. Höftadduktion och -abduktion mättes unilateralt i en sidliggande position och den bilaterala höftadduktorstyrkan mättes i ett squeeze-test i en ryggliggande position. Ett tillägg av en extern fixation av dynamometern applicerades vid testtillfället. Resultat: Styrkevärden (medelvärde, SD ±) var: höftabduktion dominant ben 1,94 ± 0,3 Nm/kg, icke-dominant ben 1,81± 0,3 Nm/kg, höftadduktion dominant ben 1,61 ± 0,3 Nm/kg, icke-dominant ben 1,51 ± 0,3 Nm/kg, squeeze-test 4,11 ± 0,5 N. Styrkekvot adduktion/abduktion var 0,83 dominant ben och 0,84 icke-dominant ben. Det dominanta benet var signifikant starkare (p<0,05) i både höftadduktion och -abduktion, 7 % respektive 8 %. Konklusion: För damfotbollsspelare var det dominanta benet signifikant starkare i både höftadduktion och -abduktion. Höftabduktorerna var signifikant starkare än adduktorerna i både det dominanta och icke-dominanta benet med en styrkekvot adduktorerna/abduktorerna på 0,83 respektive 0,84. / Introduction: Hip strength is an important physical factor in soccer for both performance and for injury prevention. Despite this normative isometric strength values are lacking for hip adduction and abduction in healthy women’s soccer players. Aim: The aim of this cross-sectional study was to examine the isometric hip strength in adduction, unilateral and bilateral, and hip abduction unilateral with a handheld dynamometer in healthy women's soccer players. Methods: 29 healthy female elite soccer players were included in the study. The isometric hip strength was measured one time in the pre-season with a hand-held dynamometer. Hip adduction and abduction were measured unilaterally in a side lying position and the bilateral hip adductor strength was measured in a squeeze test in a supine position. An addition of an external fixation of the dynamometer was applied during testing. Results: Strength values (mean, SD ±) were: hip abduction dominant leg 1,94 ± 0,3 Nm/kg, non-dominant leg 1,81± 0,3 Nm/kg, hip adduction dominant leg 1,61 ± 0,3 Nm/kg, non-dominant leg 1,51 ± 0,3 Nm/kg, squeeze-test 4.11 ± 0.5 N. The strength ratio of adduction/abduction were 0,83 dominant leg and 0,84 non-dominant leg. The dominant leg was significantly stronger (p<0,05) in both hip abduction and adduction, 7 % and 8 %, respectively. Conclusion: For women’s soccer players the dominant leg was significantly stronger in both hip abduction and adduction. The hip abductors were significantly stronger than the adductors in both the dominant and non-dominant leg with a strength ratio adductor/abductor 0,83 and 0,84 respectively.
64

Increasing the specific speed of simple microhydro propeller turbines

Fuller, Adam Michael January 2011 (has links)
The late University of Canterbury civil engineering lecturer Peter Giddens developed a range of simple microhydro turbines, with publications from as early as the 1980s. He considered that a range of simple but well-designed turbines which covered the gamut of possible small sites would be more useful than any single turbine. He started with radial inflow turbines, then set about extending their range of applicability by increasing specific speed. That extension was continued by the research in this thesis, which aimed to produce a design with a minimum efficiency of 70 % at a specific speed of at least 600 (rev/min, kW, m). Achieving those targets would differentiate it from existing microhydro designs. In order to reach those performance targets, the volute, runner, and draft tube were examined through experiment and computational fluid dynamics models to characterize past designs and test the validity of their embodied assumptions. A prototype with a design specific speed of 650 was built and fully characterized by dynamometer testing. Measurements of the outlet velocity distribution of two of Peter Giddens’s volutes confirmed that single tangential inlet volutes are not torque-free when certain geometric conditions are met; swirl increased through those volutes by 70 % or more depending on the design. A new overall turbine design was proposed, where axial flow enters the runner and swirling flows leaves it. This required the design of a novel volute. Through computational analysis, the effect of swirling flow entering the conical draft tube was shown to affect its pressure recovery: negatively for draft tubes with small angles, positively for larger angles. It was shown that the peak pressure recovery of an optimum draft tube was not likely to be improved upon by the use of swirl, and since there was uncertainty in the analysis, a conservative draft tube was specified for the prototype. A flat-bladed runner was designed for the prototype and computational modeling indicated its performance would be sensitive to small changes in flow angle. Despite that sensitivity — an intrinsic property of high specific speed runner velocity triangles — the computational model was shown to give good predictions of the runner flow characteristics, although not its effciency. Finally, a 1.2 kW prototype was built and achieved a peak net effciency of 64 % as defined by the American Society of Mechanical Engineers at a net head of 2.07 m, a flowrate of 94 L/s, and a runner shaft speed of 1670 rev/min, corresponding to a specific speed of 740. Maximum measured runner efficiency of 87 % also occurred at those conditions. Compared to existing designs, that performance extended the operational envelope of microhydro turbines considerably. A three-zone computational model of the entire prototype was assembled and trialled, but not validated. It is concluded that for efficient high specific speed turbines, volute swirl characteristics must be known with confidence, as the volute sets the conditions at the leading edge for peak runner efficiency. A simple but efficient runner may be made using flat blades, showing the potential for this geometry even when made by limited workshops. Adding a free-vortex tangential velocity distribution to the inlet flow of a stalled conical draft tube may increase its pressure recovery, although it is not likely to exceed the best performance obtainable with axial inlet flow. Therefore taking measures to reduce the peak fluid velocity entering the draft tube could be more beneficial to overall performance than seeking outright improvements in draft tube pressure recovery.
65

Predictive adaptive cruise control in an embedded environment. / Controle de cruzeiro adaptativo preditivo em um ambiente embarcado.

Brugnolli, Mateus Mussi 31 July 2018 (has links)
The development of Advanced Driving Assistance Systems (ADAS) produces comfort and safety through the application of several control theories. One of these systems is the Adaptive Cruise Control (ACC). In this work, a distribution of two control loops of such system is developed for an embedded application to a vehicle. The vehicle model was estimated using the system identification theory. An outer loop control manages the radar data to compute a suitable cruise speed, and an inner loop control aims for the vehicle to reach the cruise speed given a desired performance. For the inner loop, it is used two different approaches of model predictive control: a finite horizon prediction control, known as MPC, and an infinite horizon prediction control, known as IHMPC. Both controllers were embedded in a microcontroller able to communicate directly with the electronic unit of the vehicle. This work validates its controllers using simulations with varying systems and practical experiments with the aid of a dynamometer. Both predictive controllers had a satisfactory performance, providing safety to the passengers. / A inclusão de sistemas avançados para assistência de direção (ADAS) tem beneficiado o conforto e segurança através da aplicação de diversas teorias de controle. Um destes sistemas é o Sistema de Controle de Cruzeiro Adaptativo. Neste trabalho, é usado uma distribuição de duas malhas de controle para uma implementação embarcada em um carro de um Controle de Cruzeiro Adaptativo. O modelo do veículo foi estimado usando a teoria de identificação de sistemas. O controle da malha externa utiliza dados de um radar para calcular uma velocidade de cruzeiro apropriada, enquanto o controle da malha interna busca o acionamento do veículo para atingir a velocidade de cruzeiro com um desempenho desejado. Para a malha interna, é utilizado duas abordagens do controle preditivo baseado em modelo: um controle com horizonte de predição finito, e um controle com horizonte de predição infinito, conhecido como IHMPC. Ambos controladores foram embarcados em um microcontrolador capaz de comunicar diretamente com a unidade eletrônica do veículo. Este trabalho valida estes controladores através de simulações com sistemas variantes e experimentos práticos com o auxílio de um dinamômetro. Ambos controladores preditivos apresentaram desempenho satisfatório, fornecendo segurança para os passageiros.
66

Emissão de amônia de veículo automotor leve e sua  importância para a Saúde Ambiental / Ammonia emission from light duty vehicle and its importance for the environmental health

Borsari, Vanderlei 09 March 2015 (has links)
Introdução - A amônia (NH3) é um poluente atmosférico cuja emissão é em parte provocada por atividades antrópicas. A geração de energia através da queima de combustíveis é uma dessas atividades, dentro da qual, o setor de transporte e principalmente os veículos automotores rodoviários são uma fonte considerável das emissões de poluentes. Além de afetar diretamente a saúde humana, a amônia participa de reações na atmosfera que geram como poluente secundário, material particulado fino. Objetivo - Verificar, em veículo com motor de ignição por centelha (ciclo Otto), os valores da emissão de amônia, utilizando os combustíveis gasool 22 (gasolina contendo 22 por cento em volume de etanol anidro), etanol hidratado carburante (EHC) e gás natural veicular (GNV), com e sem a presença de elemento catalítico (catalisador). Métodos - O veículo foi ensaiado em dinamômetro de chassis, seguindo ciclo de condução e amostragem dos poluentes conforme Norma ABNT NBR 6601, para medição da emissão de escapamento, pela Norma ABNT NBR 7024, para medição de autonomia; e seguindo os ciclos de condução congestionamento (NYCC) e agressivo (US-06), adotados pela Agência de proteção ambiental dos EUA (USEPA). Além dos métodos de análise dos gases prescritos nessas Normas, foi utilizado o método FTIR (Fourier Transform InfraRed) para medição de NH3 e de N2O. Resultados - As emissões de amônia encontradas foram: média de 1,06 ± 0,03 mg/km, 1,34 ± 0,42 mg/km e 1,22 ± 0,59 mg/km antes do catalisador; e de 4,16 ± 0,65 mg/km, 3,80 ± 1,60 mg/km e 3,88 ± 0,06 mg/km nas medições após o catalisador, respectivamente para os combustíveis GNV, EHC e gasool 22. Os valores médios de emissão de amônia obtidos nos ensaios com a utilização de gasool 22 com teores de enxofre de 50 ppm e 350 ppm foram respectivamente de 3,26 ± 0,51 mg/km e 3,88 ± 0,06 mg/km. Os valores médios de emissão de amônia para os ciclos FTP-75, NYCC e US-06, foram respectivamente: 4,16 ± 0,65 mg/km, 17,30 ± 3,72 mg/km e 24,91 ± 2,71 mg/km para o combustível GNV; 3,80 ± 1,60 mg/km, 11,46 ± 1,04 mg/km e 5,47 ± 0,44 mg/km para o combustível EHC; e 3,26 ± 0,51 mg/km, 9,51 ± 1,32 mg/km e 15,82 ± 2,29 mg/km para o combustível gasool 22. Conclusão - De forma geral a emissão média de amônia medida antes do catalisador foi menor do que a medição efetuada após o catalisador para todos os combustíveis. Não foi detectada diferença significativa entre os valores de emissão de amônia feitos com dois teores diferentes de concentração de enxofre no gasool 22. Em linhas gerais a emissão de amônia mostrou-se dependente da forma de condução do veículo, apresentando valores superiores de emissão em relação ao ciclo de condução urbana (FTP-75), quando o veículo foi ensaiado seguindo os ciclos de condução NYCC e US- 06. Em princípio a emissão veicular de amônia pode ser importante na formação de material particulado fino em ambiente urbano, no qual é provável que as fontes tradicionais de emissão de amônia, como as atividades agrícolas, não sejam significativas. / Introduction - Ammonia (NH3) is an air pollutant whose emission is partly caused by human activities. Energy generation by burning fuels is one of those activities. In this area, the transportation sector has in on-road motor vehicles the major source of pollutant emissions. In addition to directly affect the human health, ammonia participates in atmospheric reactions that generate, as secondary pollutant, fine particulate matter. Objective - Verify in a vehicle with spark-ignition engine (Otto cycle), the values of ammonia emissions using the fuels gasohol 22, hydrous ethanol fuel (EHC) and compressed natural gas (CNG), with and without the presence of catalytic element (catalyst). Methods - The vehicle was tested on chassis dynamometer, following driving cycle and sampling of pollutants prescribed by ABNT NBR 6601 standard, for measuring exhaust emissions, and by ABNT NBR 7024, for measuring autonomy; and following the congestion (NYCC) and aggressive (US-06) driving cycles, adopted by the Environmental Protection Agency of USA (USEPA). In addition to the methods of gas analysis prescribed in these standards, the FTIR (Fourier Transform InfraRed) method was used for the measurement of NH3 and N2O. Results - Ammonia emissions were: average 1.06 ± 0.03 mg/km, 1.34 ± 0.42 mg/km and 1.22 ± 0.59 mg/km before the catalyst; and 4.16 ± 0.65 mg/km, 3.80 ± 1.60 mg/km and 3.88 ± 0.06 mg/km in measurements after the catalyst, respectively for the CNG, gasohol 22 and EHC fuels. Average values of ammonia emissions from tests with the use of gasohol 22 with sulfur content of 50 ppm and 350 ppm were respectively 3.26 ± 0.51 mg/km and 3.88 ± 0.06 mg/km. The average values of ammonia emissions for the FTP-75, NYCC and US-06 cycles, respectively, were: 4.16 ± 0.65 mg/km, 17.30 ± 3.72 mg/km and 24.91 ± 2.71 mg/km for the CNG fuel; 3.80 ± 1.60 mg/km, 11.46 ± 1.04 mg/km and 5.47 ± 0.44 mg/km for EHC fuel; and 3.26 ± 0.51 mg/km, 9.51 ± 1.32 mg/km and 15.82 ± 2.29 mg/km for the gasohol 22 fuel. Conclusion - In general, the average ammonia emissions measured before the catalyst was lower than the measurements made after the catalyst, for all fuels. There was no significant difference between the emission of ammonia made with two different levels of sulfur concentration in gasohol 22. Broadly the ammonia emission was dependent on the manner of driving of the vehicle, with higher emission values, compared to the urban driving cycle (FTP-75), when the vehicle was tested following the driving cycles NYCC and US-06. In principle vehicular emission of ammonia may be important in the formation of fine particulate matter in an urban environment in which it is likely that traditional sources of ammonia emissions, such as agricultural activities, are not significant.
67

Correlação da classificação funcional de atletas de basquete em cadeira de rodas com análise isocinética dos flexores, extensores e limites de estabilidade do tronco / Correlation of Wheelchair basketball functional classification system with Isokinetic analysis of trunk muscle strength and limits of stability

Santos, Sileno da Silva 26 November 2013 (has links)
INTRODUÇÃO. A força muscular e o equilíbrio do tronco são os aspectos mais importantes para a determinação da classificação funcional de atletas de basquetebol em cadeira de rodas. O objetivo deste estudo foi analisar e correlacionar a força muscular e os limites de estabilidade do tronco de acordo com a classificação funcional para atletas de basquetebol em cadeira de rodas. MÉTODOS. Quarenta e dois atletas, com classificação funcional homologada pela federação paulista da modalidade, distribuídos nas quatro classes do Basquetebol em Cadeira de Rodas (Classe 1 n= 11; Classe 2 n=11; Classe 3 n= 9; Classe 4 n=11) com média de idade de 28,3±7.4 (16-46) anos, do sexo masculino tiveram a força muscular e equilíbrio de tronco avaliados. A força do tronco foi avaliada nos músculos extensores e flexores utilizando o dinamômetro isocinético Biodex® de forma isométrica com 15 º de amplitude. Os atletas realizaram uma série de 10 repetições com 15 segundos de descanso entre cada repetição. O equilíbrio do tronco foi avaliado no equipamento Balance Master® e o teste utilizado foi o de Limites de Estabilidade (LOS) de forma adaptada. Os atletas, sentados em um banco, realizaram movimentos voluntários do tronco em oito direções no plano frontal e lateral. Os movimentos foram feitos no sentido horário, ao redor de um perímetro, visualizado pelo paciente em um monitor e que representa o limite de 100% de deslocamento dado pelo equipamento. RESULTADOS. Considerando a distribuição dos atletas nas classes, houve diferença significativa na comparação dos índices de força muscular e equilíbrio entre as classes 1x3; 1x4 e 2x4. Houve correlação negativa (moderada) entre a força muscular do tronco em flexão e o DM (r=-.68, p=.02. Houve correlação positiva (forte) na classe 3 da força muscular do tronco em extensão e o DM (r=.92 p=0,001). CONCLUSÃO. A força muscular isométrica de flexão e extensão do tronco e os índices de equilíbrios de VD e DM nas direções anterior, posterior aumentam progressivamente com as classes e apresentam maiores diferenças na comparação entre as classes 1 e 3 e 1 e 4 e 2 e 4. Não houve correlação entre a força muscular isométrica dos flexores e extensores do tronco e os limites de estabilidade de acordo com a classificação funcional do BCR / BACKGROUND. Trunk muscle strength and balance are very important in defining the class of wheelchair basketball (WCB) athletes. This study aims to correlate and analyze trunk muscle strength and balance among high-performance Brazilian WCB athletes with their functional classification. METHODS. Forty-two male athletes of mean age 28.3±7.4 years (16-46) were divided into four groups based on WCB classes as follow: class 1 n=11; class 2 n=11; class 3 n=9; and class 4 n=11. The athletes performed a set of 10 repetitions of trunk flexion and extension with 15 seconds of rest between each repetition using the BiodexR isokinetic dynamometer in isometric form, with amplitude 15° to evaluate trunk muscle strength. In order to evaluate trunk balance, using the Balance Master® equipment and the Limits of Stability test (LOS), the athletes made voluntary trunk movements in eight directions (clockwise) in the frontal and lateral planes while seated on a bench. During the test, the athletes could view the movements on a monitor that represented the 100% displacement limit given by the equipment. RESULTS. There were significant differences in comparisons of trunk muscle strength and LOS in the classes 1vs.3, 1vs.4 and 2 vs.4. There was moderate negative correlation between trunk muscle strength in flexion and maximum excursion (r=-0.68; p=0.02). There was a strong positive correlation in class 3 between trunk muscle strength in extension and maximum excursion (r=0.92;p= 0.001). CONCLUSION. There was no correlation of isometric trunk muscle strength in flexion and extension and LOS indices, according to the functional classification of the WCB athletes
68

Emissão de amônia de veículo automotor leve e sua  importância para a Saúde Ambiental / Ammonia emission from light duty vehicle and its importance for the environmental health

Vanderlei Borsari 09 March 2015 (has links)
Introdução - A amônia (NH3) é um poluente atmosférico cuja emissão é em parte provocada por atividades antrópicas. A geração de energia através da queima de combustíveis é uma dessas atividades, dentro da qual, o setor de transporte e principalmente os veículos automotores rodoviários são uma fonte considerável das emissões de poluentes. Além de afetar diretamente a saúde humana, a amônia participa de reações na atmosfera que geram como poluente secundário, material particulado fino. Objetivo - Verificar, em veículo com motor de ignição por centelha (ciclo Otto), os valores da emissão de amônia, utilizando os combustíveis gasool 22 (gasolina contendo 22 por cento em volume de etanol anidro), etanol hidratado carburante (EHC) e gás natural veicular (GNV), com e sem a presença de elemento catalítico (catalisador). Métodos - O veículo foi ensaiado em dinamômetro de chassis, seguindo ciclo de condução e amostragem dos poluentes conforme Norma ABNT NBR 6601, para medição da emissão de escapamento, pela Norma ABNT NBR 7024, para medição de autonomia; e seguindo os ciclos de condução congestionamento (NYCC) e agressivo (US-06), adotados pela Agência de proteção ambiental dos EUA (USEPA). Além dos métodos de análise dos gases prescritos nessas Normas, foi utilizado o método FTIR (Fourier Transform InfraRed) para medição de NH3 e de N2O. Resultados - As emissões de amônia encontradas foram: média de 1,06 ± 0,03 mg/km, 1,34 ± 0,42 mg/km e 1,22 ± 0,59 mg/km antes do catalisador; e de 4,16 ± 0,65 mg/km, 3,80 ± 1,60 mg/km e 3,88 ± 0,06 mg/km nas medições após o catalisador, respectivamente para os combustíveis GNV, EHC e gasool 22. Os valores médios de emissão de amônia obtidos nos ensaios com a utilização de gasool 22 com teores de enxofre de 50 ppm e 350 ppm foram respectivamente de 3,26 ± 0,51 mg/km e 3,88 ± 0,06 mg/km. Os valores médios de emissão de amônia para os ciclos FTP-75, NYCC e US-06, foram respectivamente: 4,16 ± 0,65 mg/km, 17,30 ± 3,72 mg/km e 24,91 ± 2,71 mg/km para o combustível GNV; 3,80 ± 1,60 mg/km, 11,46 ± 1,04 mg/km e 5,47 ± 0,44 mg/km para o combustível EHC; e 3,26 ± 0,51 mg/km, 9,51 ± 1,32 mg/km e 15,82 ± 2,29 mg/km para o combustível gasool 22. Conclusão - De forma geral a emissão média de amônia medida antes do catalisador foi menor do que a medição efetuada após o catalisador para todos os combustíveis. Não foi detectada diferença significativa entre os valores de emissão de amônia feitos com dois teores diferentes de concentração de enxofre no gasool 22. Em linhas gerais a emissão de amônia mostrou-se dependente da forma de condução do veículo, apresentando valores superiores de emissão em relação ao ciclo de condução urbana (FTP-75), quando o veículo foi ensaiado seguindo os ciclos de condução NYCC e US- 06. Em princípio a emissão veicular de amônia pode ser importante na formação de material particulado fino em ambiente urbano, no qual é provável que as fontes tradicionais de emissão de amônia, como as atividades agrícolas, não sejam significativas. / Introduction - Ammonia (NH3) is an air pollutant whose emission is partly caused by human activities. Energy generation by burning fuels is one of those activities. In this area, the transportation sector has in on-road motor vehicles the major source of pollutant emissions. In addition to directly affect the human health, ammonia participates in atmospheric reactions that generate, as secondary pollutant, fine particulate matter. Objective - Verify in a vehicle with spark-ignition engine (Otto cycle), the values of ammonia emissions using the fuels gasohol 22, hydrous ethanol fuel (EHC) and compressed natural gas (CNG), with and without the presence of catalytic element (catalyst). Methods - The vehicle was tested on chassis dynamometer, following driving cycle and sampling of pollutants prescribed by ABNT NBR 6601 standard, for measuring exhaust emissions, and by ABNT NBR 7024, for measuring autonomy; and following the congestion (NYCC) and aggressive (US-06) driving cycles, adopted by the Environmental Protection Agency of USA (USEPA). In addition to the methods of gas analysis prescribed in these standards, the FTIR (Fourier Transform InfraRed) method was used for the measurement of NH3 and N2O. Results - Ammonia emissions were: average 1.06 ± 0.03 mg/km, 1.34 ± 0.42 mg/km and 1.22 ± 0.59 mg/km before the catalyst; and 4.16 ± 0.65 mg/km, 3.80 ± 1.60 mg/km and 3.88 ± 0.06 mg/km in measurements after the catalyst, respectively for the CNG, gasohol 22 and EHC fuels. Average values of ammonia emissions from tests with the use of gasohol 22 with sulfur content of 50 ppm and 350 ppm were respectively 3.26 ± 0.51 mg/km and 3.88 ± 0.06 mg/km. The average values of ammonia emissions for the FTP-75, NYCC and US-06 cycles, respectively, were: 4.16 ± 0.65 mg/km, 17.30 ± 3.72 mg/km and 24.91 ± 2.71 mg/km for the CNG fuel; 3.80 ± 1.60 mg/km, 11.46 ± 1.04 mg/km and 5.47 ± 0.44 mg/km for EHC fuel; and 3.26 ± 0.51 mg/km, 9.51 ± 1.32 mg/km and 15.82 ± 2.29 mg/km for the gasohol 22 fuel. Conclusion - In general, the average ammonia emissions measured before the catalyst was lower than the measurements made after the catalyst, for all fuels. There was no significant difference between the emission of ammonia made with two different levels of sulfur concentration in gasohol 22. Broadly the ammonia emission was dependent on the manner of driving of the vehicle, with higher emission values, compared to the urban driving cycle (FTP-75), when the vehicle was tested following the driving cycles NYCC and US-06. In principle vehicular emission of ammonia may be important in the formation of fine particulate matter in an urban environment in which it is likely that traditional sources of ammonia emissions, such as agricultural activities, are not significant.
69

Predictive adaptive cruise control in an embedded environment. / Controle de cruzeiro adaptativo preditivo em um ambiente embarcado.

Mateus Mussi Brugnolli 31 July 2018 (has links)
The development of Advanced Driving Assistance Systems (ADAS) produces comfort and safety through the application of several control theories. One of these systems is the Adaptive Cruise Control (ACC). In this work, a distribution of two control loops of such system is developed for an embedded application to a vehicle. The vehicle model was estimated using the system identification theory. An outer loop control manages the radar data to compute a suitable cruise speed, and an inner loop control aims for the vehicle to reach the cruise speed given a desired performance. For the inner loop, it is used two different approaches of model predictive control: a finite horizon prediction control, known as MPC, and an infinite horizon prediction control, known as IHMPC. Both controllers were embedded in a microcontroller able to communicate directly with the electronic unit of the vehicle. This work validates its controllers using simulations with varying systems and practical experiments with the aid of a dynamometer. Both predictive controllers had a satisfactory performance, providing safety to the passengers. / A inclusão de sistemas avançados para assistência de direção (ADAS) tem beneficiado o conforto e segurança através da aplicação de diversas teorias de controle. Um destes sistemas é o Sistema de Controle de Cruzeiro Adaptativo. Neste trabalho, é usado uma distribuição de duas malhas de controle para uma implementação embarcada em um carro de um Controle de Cruzeiro Adaptativo. O modelo do veículo foi estimado usando a teoria de identificação de sistemas. O controle da malha externa utiliza dados de um radar para calcular uma velocidade de cruzeiro apropriada, enquanto o controle da malha interna busca o acionamento do veículo para atingir a velocidade de cruzeiro com um desempenho desejado. Para a malha interna, é utilizado duas abordagens do controle preditivo baseado em modelo: um controle com horizonte de predição finito, e um controle com horizonte de predição infinito, conhecido como IHMPC. Ambos controladores foram embarcados em um microcontrolador capaz de comunicar diretamente com a unidade eletrônica do veículo. Este trabalho valida estes controladores através de simulações com sistemas variantes e experimentos práticos com o auxílio de um dinamômetro. Ambos controladores preditivos apresentaram desempenho satisfatório, fornecendo segurança para os passageiros.
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Avaliação da força de preensão digital em trabalhadores de enfermagem / Assessment of digital grip strength in nursing professionals

Lelis, Cheila Maíra 18 December 2014 (has links)
Objetivo: O presente estudo pretendeu avaliar a força de preensão digital em trabalhadores de enfermagem a fim de determinar as médias desta força e correlacionar com os fatores pessoais e ocupacionais Métodos: Estudo descritivo, correlacional, quantitativo, realizado em um hospital de ensino de Ribeirão Preto. Os sujeitos foram categorizados por meio de um questionário que abordou características pessoais e profissionais; para a mensuração da força de preensão digital foi utilizado um dinamômetro hidráulico Preston Pinch Gauge® (North Coast Medical - Estados Unidos), por meio deste foram realizadas três mensurações consecutivas para cada medida de força e utilizou-se a média destas pinças para as análises. As coletas de dados foram realizadas em 2013, este estudo recebeu a aprovação de Comitê de Ética e Pesquisa. Compuseram a amostra 41 profissionais de enfermagem do sexo feminino, que trabalhavam no período matutino. Foram realizados testes estatísticos e o nível de significância considerado foi ? = 0, 05; o programa utilizado nas análises foi a IBM SPSS (Statistical Package for Social Science) versão 22.0. Resultados: As trabalhadoras encontravam-se na faixa etária entre 21 e 60 anos; 56,1% eram casadas e 58,5% possuíam filhos; com relação ao nível de escolaridade 43,9% tinham ensino médio completo.No que diz respeito ao vínculo empregatício atual na enfermagem, 56,1% faziam seis horas semanais e 68,3% horas extras neste vinculo; 7,3% possuíam outro vínculo na área da enfermagem, porém sem realizar horas extras. Já se afastaram do trabalho por motivo de doença 63,4%; referiram sentir dor no dedo da mão 26,8%; 95,1% das trabalhadoras realizavam atividades domésticas em sua própria casa; 70,7% não praticavam atividade física; 58,5% possuíam algum tipo de atividade de lazer, foram observadas ainda doenças osteomusculares (27,3%). Os valores da médias gerais da pinças foram: 3,64 (kgf) polpa-a-polpa,3,85 (kgf), trípode; 6,08(kgf) lateral.Conclusão: Mesmo que não se tenha identificado uma porcentagem alta em relação a carga horária de trabalho associada as horas extras e o duplo vínculo, as variáveis independentes identificadas, influenciaram o desempenho dos testes de preensão de pinça, consequentemente, na diminuição bilateral das forças de preensão das pinças digitais estudadas. Entre as categorias profissionais e as médias de pinça houve correlação positiva e significativa, destacando pinças polpa-a-polpa (mão dominante). A força de preensão digital pode ser um indicador para determinar a função da mão e poder ser usada para indicar o grau de disfunção da extremidade superior acometida, não se pode afirmar que existam alterações relacionadas aos membros superiores das trabalhadoras de enfermagem, mesmo tendo em vista que a literatura infere que muitas das patologias associadas ao membro superior têm como alguns de seus sintomas iniciais a diminuição da força de pinças, fraqueza e dor nos dedos. Seria necessário agregar aos dados avaliados de preensão de digitais mais avaliações, como as clinicas, motoras e sensitivas. Diante do incipiente número de investigações relacionadas à força de preensão digital entre estas trabalhadoras, este estudo pretendeu contribuir na prevenção do desenvolvimento de disfunções ocupacionais, com a sugestão de inserção desta avaliação nos exames médicos admissionais, periódicos, de retorno ao trabalho e demissionais / Objective: This study aimed to evaluate the digital grip strength of nursing staff in order to determine the averages of this strength and correlate it to personal and occupational factors. Methods: Descriptive, co-relational, quantitative study carried out at a teaching hospital in Ribeirão Preto. Subjects were categorised by means of a questionnaire which addressed personal and professional characteristics; for the measurement of digital grip strength the hydraulic dynamometer Preston Pinch Gauge® (North Coast Medical - the United States) was used, with which three consecutive readings were made for each strength measurement and the mean of the pinches was used for the analysis. Data collection was performed in 2013 and this study was approved by the Research and Ethics Committee. 41 female nursing staff members composed the samples, all of whom worked in the morning. Statistical tests were made and the significance level considered was ? = 0.05; the program used for the analysis was IBM SPSS (Statistical Package for Social Science) version 22.0. Results: The workers were aged between 21 and 60 years; 56.1% were married and 58.5% had children; regarding the level of education 43.9% were high- school graduates. Concerning the current nursing employment relationship 56.1% worked six hours per week and 68.3% overtime in such relationship; 7.3% had other nursing labour bonds although not working overtime. 63.4% were away from work due to health complications; 26.8% indicated to suffer from finger pain; 95.1% of the workers performed household chores in their own houses; 70.7% did not do any physical activity; 58.5% had some kind of leisure activity, and osteomuscular conditions were still observed (27.3%). General mean values found were: 3.64 (kgf) pulp to pulp, 3.85 (kgf) three points and 6.08 (kgf) lateral pinch. Conclusion: Although there was not an identification of a higher percentage related to the working hours associated to overtime and double labour bond, the independent variables identified affected the pinch grip test performance, consequently reducing bilaterally the digital pinch grip strengths analysed. There was positive and significant correlation between the professional categories and the pinch means, highlighting pulp to pulp pinch(dominant hand). Digital grip strength can be an indicator to determine hand function and can be used to demonstrate the level of dysfunction of the affected upper limb ends, but it cannot be stated that there are alterations related to the upper limbs of nursing staff, even considering that the literature infers that many pathologies associated to the upper limbs present the reduction of pinch strength and finger weakness and pain as some of their initial symptoms. It would be necessary to add more evaluations to the already analysed data on digital grip, such as clinical, motor and sensitive evaluations. Before the incipient number of investigations related to the digital grip force among these workers, this study intended to contribute to the prevention of the development of occupational dysfunctions, suggesting the further introduction of this evaluation to admission, periodic, return to work and discharge medical examinations

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