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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.
21

Torque Sensor based Powertrain Control / Momentsensorbaserad drivlinereglering

Marciszko, Fredrik January 2004 (has links)
The transmission is probably the drivetrain component with the greatest impact on driveability of an automatic transmission equipped vehicle. Since the driver only has an indirect influence on the gear shift timing, except for situations like kick-down accelerations, it is desirable to improve shift quality as perceived by the driver. However, improving shift quality is a problem normally diametrically opposed to minimizing transmission clutch energy dissipation. The latter has a great impact on transmission lifetime, and has to be defined and taken into consideration along with the notion of shift quality. The main focus of this thesis is the modeling of a drivetrain of an automatic transmission vehicle, and the implementation in MatLab/Simulink, including the first to second gear upshift. The resulting plant based on the derived equations is validated using data from a test vehicle equipped with a torque sensor located at the transmission output shaft. The shaft torque is more or less proportional to the driveline jerk, and hence of great interest for control purposes. Control strategies are discussed and a PID controller structure is developed to control the first to second gear upshift, as opposed to the traditional open-loop upshift control. Furthermore, the proposed controller structure uses the transmission output torque and the differential speed of the engaging clutch as inputs, to control the clutch pressure and the engine output torque, respectively. The structure is unsophisticated and transparent compared to other approaches, but shows great theoretical results in terms of improved shift quality and decreased clutch wear.
22

Silagem de grãos úmidos de milho na alimentação de frangos Label Rouge com suplementação de acidificante / High moisture corn grain silage in the feeding of Label Rouge broilers supplemented with acidifying

Frank, Rafael 17 December 2014 (has links)
Made available in DSpace on 2017-07-10T17:48:06Z (GMT). No. of bitstreams: 1 Rafael_Frank.pdf: 1053662 bytes, checksum: eb7ec01d3ec53c5bff8738bcd9ca4984 (MD5) Previous issue date: 2014-12-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this study was to determine the aerobic stability, centesimal composition and energy values and the amino acids digestibility of high moisture corn grain silage (HMCS), and evaluate the effect of HMCS inclusion in different levels in diets on performance and gut parameters of Label Rouge broilers. In Experiment 1, to determine the applicability of inoculants usage the growth of main microorganisms involved in fermentation of high moisture corn grain silage was evaluated among time periods, as well as aerobic stability when silages were made with or without the addition of inoculum Lactobacillus plantarum + Propionibacterium acidipropionici. Significant changes were observed for temperature and pH as a function of storage time and use of inoculum. For the population of fungi and entero-bacteria a significant decrease in function of the storage time was observed more expressive for silages in which the inoculum was applied. Changes in all populations of microorganisms studied as a function of storage time were observed. For the chemical composition differences were obtained for dry matter, neutral detergent fiber and acid detergent fiber, when we used silage additive and changes in the concentration of acid detergent fiber in function of the different storage times. Aerobic stability was of 156 hours for silage ensiled by 28 days, without significant difference for inoculation. When ensiled for 56 days, the silage inoculated presented greater stability (60 hours) when compared to no inoculant (32 hours). The high moisture grain corn silage with microbial inoculum based on Lactobacillus plantarum and Propionibacterium acidipropionici was able to reduce the population of fungi and enterobacteria. In Experiment 2, to determine the energy values of high moisture corn silage (HMCS), male broilers from 21 to 31 days old were used, averaging 765 ± 1.70 g. The experimental period lasted ten days, five of adaptation and five for collection. The HMCS replaced in 10, 20, 30 and 40% the reference ration (RR). The method of analysis was the total excreta collection for subsequent analysis of apparent metabolizable energy (AME) and AME corrected for nitrogen balance (AMEn) of HMCS. To determine the amino acid values, the technique of forced feeding was applied in 12 cecectomized Leghorn roosters, with average weight of 1912.10 ± 133.73 g. Six animals received HMCS and the other six were fasted. At the end of the excreta collection period, the essential amino acid profile was determined, as the true digestibility coefficients and the true digestible content of amino acids in HMCS. This food presented average values of 2283 kcal/kg of EMA and 2272 kcal/kg of AMEn, and these energy values were negatively influenced by the inclusion levels of HMCS. Cystine presented the lower digestibility coefficients while leucine and glutamine had the highest digestibility and digestible amino acids values. In Experiment 3, one thousand and two hundred Label Rouge chicks with an average initial weight of 41 ±0.55g were distributed in a completely randomized design, in a factorial 2x5 (with and without the addition of acidifying X 0, 25, 50, 75 and 100% of high-moisture corn grain silage - HMCS). The weight gain (WG), feed intake (FI) and feed conversion (F:G) were determined, beyond the intestinal morphometric analysis and microbiota, carcass yield and cuts. From 1-28 and 1-63 days there was a quadratic effect (P<0.05) of HMCS on FI and F:G. There was interaction (P<0.05) between the levels of HMCS and the addition of acidifying for carcass yield and cuts (wing and chest) and liver of females. Males presented interaction (P<0.05) between levels of HMCS and acidifying for carcass, drumstick, chest and fat. There was an interaction (P<0.05) between HMCS and the inclusion of acidifying in the counting of Lactobacillus and Clostridium at 28 days old and for Lactobacillus at 63 days old. At 28 days there was an interaction (P<0.05) between HMCS and the inclusion of acidifying for villi height. At 63 days there was and quadratic effect of HMCS and the acidifying for crypts, which presented higher diameter for treatments without acidifying. The results suggest that jerk chickens fed up to 50% of HMCS with acidifying had good carcass yield and cuts and had no damage on intestinal development / O objetivo deste trabalho foi determinar a estabilidade aeróbica, a composição bromatológica e energética e a digestibilidade de aminoácidos da silagem de grãos úmidos de milho (SGUM), além de avaliar o desempenho e parâmetros intestinais de frangos Label Rouge recebendo diferentes níveis de SGUM na alimentação. No Experimento 1, para determinar a aplicabilidade da utilização de inóculos, foi avaliado o crescimento dos principais microrganismos envolvidos na fermentação da SGUM ao longo do tempo, assim como a estabilidade aeróbia quando silagens foram confeccionadas com ou sem adição de inóculo Lactobacillus plantarum + Propionibacterium acidipropionici. Foram observadas alterações significativas para temperatura e pH em função de tempo de estocagem e utilização de inóculo. Para a população de fungos e enterobactérias foi observada redução significativa em função do tempo de armazenamento de forma mais expressiva para as silagens em que foi aplicado o inóculo. Observou-se alteração em todas as populações de microrganismos estudados em função do tempo de armazenamento. Para a composição química, foram obtidas diferenças para matéria seca, fibra em detergente neutro e fibra em detergente ácido, quando foi utilizado inoculante, e alterações na concentração de fibra em detergente ácido em função dos diferentes tempos de armazenagem. A estabilidade aeróbica foi de 156 horas para silagens ensiladas por 28 dias, sem diferença significativa para inoculação. Quando ensilada por 56 dias, a silagem inoculada apresentou maior estabilidade (60 horas) quando comparada à sem inoculante (32 horas). A ensilagem de grão úmido de milho com inóculo microbiano à base de Lactobacillus plantarum e Propionibacterium acidipropionici foi capaz de reduzir a população de fungos e enterobactérias. No Experimento 2, para a determinação dos valores energéticos da SGUM, foram utilizados frangos de corte machos, dos 21 aos 31dias de idade, com peso médio de 765 ± 1,70 g. O período experimental teve duração de dez dias, sendo cinco de adaptação e cinco de coleta. A SGUM substituiu em 10, 20, 30 e 40% uma ração referência (RR). O método de análise foi o de coleta total de excretas, para posterior análises de energia metabolizável aparente (EMA) e EMA corrigida pelo balanço de nitrogênio (EMAn) da SGUM. Para a determinação dos valores de aminoácidos, foi usada a técnica de alimentação forçada em 12 galos Leghorn cecectomizados, com peso médio de 1912,10 ±133,73g. Seis animais receberam a SGUM e os outros seis permaneceram em jejum. Ao final do período de coleta de excretas, foi determinado o perfil de aminoácidos essenciais, coeficientes de digestibilidade verdadeira e o conteúdo digestível verdadeiro dos aminoácidos no alimento. A SGUM apresentou valores médios de 2283 kcal/kg de EMA e 2272 kcal/kg de EMAn, sendo que os valores energéticos foram negativamente influenciados pelos níveis de inclusão da SGUM. A cistina apresentou o menor coeficiente de digestibilidade, enquanto que a leucina e a glutamina apresentaram os maiores coeficientes de digestibilidade e os valores de aminoácidos digestíveis. No Experimento 3, foram utilizados 1200 pintos da linhagem Label Rouge, com peso médio inicial de 41 ±0,55g, distribuídos em um delineamento inteiramente casualizado, em esquema fatorial 2x5, (com e sem acidificante X 0, 25, 50, 75 e 100% de silagem de grãos úmidos de milho - SGUM). Foram determinados o ganho de peso (GP), consumo de ração (CR), conversão alimentar (CA), além da análise morfométrica e de microbiota intestinal, rendimento de carcaça e de cortes. De 1 a 28 e de 1 a 63 dias, houve efeito quadrático (P<0,05) da SGUM sobre o CR e CA. Houve interação (P<0,05) entre os níveis de SGUM e a adição de acidificante para o rendimento de carcaça e de cortes (asa, peito) e fígado das fêmeas. Os machos apresentaram interação (P<0,05) entre os níveis de SGUM e o acidificante para carcaça, sobrecoxa, peito e gordura. Houve interação (P<0,05) da inclusão de SGUM e a adição ou não de acidificante para a contagem de Lactobacillus e Clostridium aos 28 dias de idade e Lactobacillus aos 63 dias de idade. Aos 28 dias, houve interação (P<0,05) entre os níveis de SGUM e a adição de acidificante para a altura dos vilos. Aos 63 dias, foi observado efeito quadrático da SGUM para o tratamento com acidificante e as criptas apresentaram maior diâmetro para o tratamento sem acidificante. Os resultados sugerem que frangos caipiras alimentados com até 50% de SGUM com acidificante apresentam boas características de carcaça e de cortes e não sofrem danos sobre os parâmetros intestinais
23

Effects of Attachment Height and Rail Material of Resistance Training Sled on Trunk Lean and Jerk During Linear Acceleration Training

Fitzgerald, Sean 05 1900 (has links)
Sprint acceleration training has been highly researched and found that resistance sleds are one of the most effective tools for maximizing training adaptations. The resistance sled is being used by many of the world leaders in athletic training but has yet to be researched for the kinetic and kinematic effects some of its key components cause. The aim of this study was to better understand the effects of the attachment height on the sled and sled rail material on the user's trunk lean and jerking effect caused by the sled. This was done because it was hypothesized that the attachment height has a direct impact on trunk lean and sled rail material has a direct impact on jerk caused by the sled. To test these assumptions, experimental and theoretical data was collected using a single subject study analyzing trunk lean and acceleration values of the sled. The results presented a significant decrease in trunk lean (more horizontal line of action) when the attachment height was raised. Additionally, no significant values were attained to support the assumption that by modifying the sled rail material, jerking effects will decrease. The results indicate that there is a direct correlation between attachment height and trunk lean. More research is needed to better understand the relationship between sled rail material and jerk.
24

Vliv senzomotorické intervence na vnímání těla a kvalitu pohybu u muzikantů hrajících na smyčcové nástroje / The influence of sensorimotor intervention on body perception and quality of movement in string musicians.

Kutinová, Eliška January 2021 (has links)
Playing a musical instrument is a very beautiful, but very physically demanding craft. Many musicians suffer from musculoskeletal pain caused, among other things, by a rigid, unchanging posture and a focus on performance at the expense of comfort. The theoretical part of the thesis deals with the influence of music production on the musculoskeletal system of the musician and the possibilities of therapy aimed at improving sensorimotor skills and kinesthesia. The practical part followed the influence of therapy inspired by the Feldenkrais method and Alexander's technique on the movement of the musician during and outside the performance. The research was conducted on 19 professional string musicians. Testing of probands consisted of measurements with inertial sensors, objective measurements of sensorimotor skills and kinesthesia and a questionnaire survey. The parameter measured by the inertial sensors was a jerk (indicates the smoothness of the movement). The results of the measurements show that, even after a single therapy, the smoothness of the chest movement improved statistically significantly.
25

Evaluation of Model-Based Design Using Rapid Control Prototyping on Forklifts / Utvärdering av modelbaserad utveckling med Rapid Control Prototyping på gaffeltruckar

Jansson, Lovisa, Nilsson, Amanda January 2019 (has links)
The purpose of this thesis is to evaluate Rapid Control Prototyping which is apart of the Model-Based Design concept that makes it possible to convenientlytest prototype control algorithms directly on the real system. The evaluation ishere done by designing two different controllers, a gain-scheduled P controllerand a linear Model Predictive Controller (mpc), for the lowering of the forks of aforklift.The two controllers are first tested in a simulation environment. The thesis con-tains two different simulation models: one physical where only minor parameteradjustments are done and one estimated black-box model. After evaluating thecontrollers in a simulation environment they are tested on a real forklift with areal-time target machine.The designed controllers have different strengths and weaknesses as one is non-linear and single variable, the P controller, and the other linear and multivariable,thempc. The P controller has a smooth movement in all situations without be-ing slow, unlike thempc. The disadvantage of the P controller compared to thempcis that there is no guarantee that the P controller will keep the speed limit,whereas thempcapproach gives such a guarantee.The better performance of the P controller outweighs the speed limit guaranteeand thus a conclusion is drawn that the nonlinearities of the system has a largereffect than the multivariable aspect. Also, another conclusion drawn is that work-ing with Model-Based Design and Rapid Control Prototyping makes it possibleto test many different ideas on a real forklift without spending a lot of time onimplementation. / Syftet med detta examensarbete är att utvärdera Rapid Control Prototyping vil-ket är en del av modellbaserad utveckling som gör det möjligt att enkelt testamodeller av styralgoritmer direkt på det riktiga systemet. Utvärderingen är gjordgenom att testa två olika regulatorer, en P-regulator med parameterstyrning ochen linjär modelbaserad prediktionsregulator (mpc), för sänkningen av gafflarnapå en truck.De två regulatorerna testas först i en simuleringsmiljö. I arbetet används två olikasimuleringsmodeller: en fysikalisk där endast mindre parameterjusteringar görsoch en estimerad black-box modell. Efter att regulatorerna utvärderas i simule-ringsmiljön testas de även på en riktig truck med hjälp av automatisk kodgenere-ring och exekvering på en dedikerad hårdvaruplattform.De konstruerade regulatorerna har olika för- och nackdelar eftersom en är olinjäroch envariabel, P-regulatorn, och en är linjär men flervariabel,mpc:n. P-regulatornhar en mjuk rörelse i alla lägen utan att bli för långsam, till skillnad frånmpc:n.Nackdelen med P-regulatorn, jämfört medmpc:n är att det inte finns någon ga-ranti för att P-regulatorn håller hastighetsbegränsningen sommpc:n gör.P-regulatorns bättre prestanda överväger garantin om att hålla hastighetsbegräns-ningen och därför dras slutsatsen att olinjäriteterna i systemet överväger effekter-na av det faktum att det också är flervariabelt. En annan slutsats är att modell-baserad utveckling och Rapid Control Prototyping gör det möjligt att testa fleraolika idéer på en riktig gaffeltruck utan att spendera för mycket tid på implemen-tationen.
26

歩行中の手先振動抑制に対する視覚情報の役割

UNO, Yoji, KAGAWA, Takahiro, TOGO, Shunta, 宇野, 洋二, 香川, 高弘, 東郷, 俊太 02 1900 (has links)
No description available.
27

Identifying a Test to Monitor Weightlifting Performance in Competitive Male and Female Weightlifters

Travis, S. Kyle, Goodin, Jacob R., Beckham, George K., Bazyler, Caleb D. 23 May 2018 (has links)
Monitoring tests are commonly used to assess weightlifter’s preparedness for competition. Although various monitoring tests have been used, it is not clear which test is the strongest indicator of weightlifting performance. Therefore, the purpose of this study was to (1) determine the relationships between vertical jump, isometric mid-thigh pull (IMTP) and weightlifting performance; and (2) compare vertical jumps to IMTP as monitoring tests of weightlifting performance in a large cohort of male and female weightlifters. Methods: Fifty-two competitive weightlifters (31 males, 21 females) participated in squat and countermovement jump testing (SJ, CMJ), and IMTP testing performed on force plates. All laboratory testing data was correlated to a recent competition where the athletes had attempted to peak. Results: Squat jump height (SJH) was the strongest correlate for men and women with the Sinclair Total (r = 0.686, p ≤ 0.01; r = 0.487, p ≤ 0.05, respectively) compared to countermovement jump height (r = 0.642, p ≤ 0.01; r = 0.413, p = 0.063), IMTP peak force allometrically scaled to body mass (r = 0.542, p ≤ 0.01; r = −0.044, p = 0.851) and rate of force development at 200 ms (r = 0.066, p = 0.723; r = 0.086, p = 0.711), respectively. Further, SJH was a stronger correlate of relative weightlifting performance compared to IMTP peak force in females (p = 0.042), but not male weightlifters (p = 0.191). Conclusions: Although CMJ and IMTP are still considered strong indicators of weightlifting performance, SJH appears to be the most indicative measure of weightlifting performance across a wide-range of performance levels. Thus, SJH can be used as a reliable measure to monitor weightlifting performance in male and female weightlifters.
28

Evaluating Multi-Modal Brain-Computer Interfaces for Controlling Arm Movements Using a Simulator of Human Reaching

Liao, James Yu-Chang 02 September 2014 (has links)
No description available.
29

Plant error compensation and jerk control for adaptive cruise control systems

Meadows, Alexander David 05 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Some problems of complex systems are internal to the system whereas other problems exist peripherally; two such problems will be explored in this thesis. First, is the issue of excessive jerk from instantaneous velocity demand changes produced by an adaptive cruise control system. Calculations will be demonstrated and an example control solution will be proposed in Chapter 3. Second, is the issue of a non-perfect plant, called an uncertain or corrupted plant. In initial control analysis, the adaptive cruise control systems are assumed to have a perfect plant; that is to say, the plant always behaves as commanded. In reality, this is seldom the case. Plant corruption may come from a variation in performance through use or misuse, or from noise or imperfections in the sensor signal data. A model for plant corruption is introduced and methods for analysis and compensation are explored in Chapter 4. To facilitate analysis, Chapter 2 discusses the concept of system identification, an order reduction tool which is employed herein. Adaptive cruise control systems are also discussed with special emphasis on the situations most likely to employ jerk limitation.
30

Commande numérique ouverte : interpolation optimisée pour l'usinage 5 axes grande vitesse des surfaces complexes

Beudaert, Xavier 04 July 2013 (has links) (PDF)
Le processus de fabrication des pièces usinées arrive à maturité concernant la fabrication assistée par ordinateur et la maîtrise du procédé d'usinage. Aujourd'hui, les perspectives d'améliorations importantes sont liées à l'optimisation de la commande numérique et de ses interactions avec le reste du processus de fabrication. L'objectif de cette thèse est donc de maîtriser les briques de base de la commande numérique pour optimiser le processus d'usinage 5 axes grande vitesse des surfaces complexes. La création d'une commande numérique ouverte nécessite le développement des algorithmes qui transforment le programme d'usinage en consignes échantillonnées pour les axes de la machine. La première partie des travaux consiste à rendre la géométrie suffisamment continue notamment pour les trajets interpolés linéairement en 5 axes qui présentent des discontinuités en tangence. Ensuite, l'interpolation temporelle du trajet crée la trajectoire d'usinage respectant les contraintes cinématiques et en particulier le jerk de chacun des 5 axes de la machine. L'implémentation matérielle de ces algorithmes permet de piloter une machine d'usinage grande vitesse 5 axes avec une commande numérique ouverte. Ainsi, les verrous technologiques associés aux commandes numériques industrielles sont levés et la chaîne numérique est entièrement contrôlée de la CFAO jusqu'au déplacement des axes. La maîtrise complète de la commande numérique offre la possibilité de définir exactement le trajet d'usinage à partir de la CAO sans introduire les écarts géométriques inhérents aux formats de description standards. L'interpolation de la trajectoire d'usinage directement sur la surface à usiner améliore de manière significative la qualité et la productivité de l'usinage des surfaces complexes. La commande numérique PREMIUM-OpenCNC permet la validation expérimentale de ces travaux et ouvre de nombreuses autres voies d'amélioration du processus de fabrication.

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