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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

Avaliação longitudinal da estabilidade do tratamento da má oclusão de Classe II com o aparelho Pendulum seguido do aparelho fixo / Longitudinal evaluation of treatment stability for class II malocclusion with a pendulum appliance followed by a fixed one

Alessio Junior, Luiz Eduardo 20 February 2009 (has links)
Compulsando a literatura nota-se uma diversidade de formas de tratamento, apoiadas em diferentes mecanismos terapêuticos, para a correção da má oclusão de Classe II. No entanto, poucos trabalhos estudam a estabilidade da correção com o aparelho Pendulum. Sendo assim, o objetivo deste estudo foi verificar a estabilidade do tratamento da Classe II em longo prazo (5 anos) com o aparelho Pendulum, seguido pelo aparelho fixo. A amostra consistiu de 20 pacientes (14 do gênero feminino e 6 do masculino). A média da idade, ao inicio do tratamento (T1), foi de 14,02 ± 1,62 anos, ao final do tratamento (T2), 18,38 ± 1,84 anos, e no pós-tratamento (T3), 22,94 ± 1,34 anos. Para a análise, foram utilizados traçados cefalométricos e modelos de estudo nas 3 fases. As variáveis nos 3 grupos, foram comparadas pela análise de variância a um critério ANOVA, considerando significativo o valor de P < 0,05. Os resultados mostraram uma grande estabilidade das variáveis cefalométricas, sendo estatisticamente diferentes somente a inclinação do primeiro molar e a posição ântero-posterior do lábio superior. A avaliação do índice PAR demonstrou que o tratamento com o aparelho Pendulum seguido pelo aparelho fixo, foi estável 5 anos pós-tratamento. Conclui-se que o tratamento da Classe II com o aparelho Pendulum e o aparelho fixo, foi estável em longo prazo. / There are, in the literature, several forms of treatment, supported by different therapeutic mechanisms for the correction of Class II malocclusion. However, a few works have studied the stability of Class II correction with the Pendulum appliance. Therefore, this study aimed at verifying the long-term stability (5 years) of a treatment with the Pendulum appliance followed by a fixed one. The sample consisted of 20 patients (14 females and 6 males). The average age at the beginning of the treatment (T1) was 14,02 ± 1,62 yrs, and at the end of the treatment (T2), 18,38 ± 1,84 yrs, and at the post-treatment (T3), 22,94 ± 1,34 yrs. Cephalometric measurements and cast models were used in the 3 phases and the variables for the 3 groups were compared by ANOVA variance analysis, by considering P<0,05, a significant value. The results show a great stability of the cephalometric variables, being statistically different, only the tipping of the 1st molar and the upper lip thickness. The PAR index assessment demonstrated that the treatment with the pendulum appliance, followed by a fixed one, was stable, 5 yrs post-treatment. It was concluded that the Class II treatment with the Pendulum appliance, followed by a fixed one, was more stable in the long term.
62

Avaliação longitudinal da estabilidade do tratamento da má oclusão de Classe II com o aparelho Pendulum seguido do aparelho fixo / Longitudinal evaluation of treatment stability for class II malocclusion with a pendulum appliance followed by a fixed one

Luiz Eduardo Alessio Junior 20 February 2009 (has links)
Compulsando a literatura nota-se uma diversidade de formas de tratamento, apoiadas em diferentes mecanismos terapêuticos, para a correção da má oclusão de Classe II. No entanto, poucos trabalhos estudam a estabilidade da correção com o aparelho Pendulum. Sendo assim, o objetivo deste estudo foi verificar a estabilidade do tratamento da Classe II em longo prazo (5 anos) com o aparelho Pendulum, seguido pelo aparelho fixo. A amostra consistiu de 20 pacientes (14 do gênero feminino e 6 do masculino). A média da idade, ao inicio do tratamento (T1), foi de 14,02 ± 1,62 anos, ao final do tratamento (T2), 18,38 ± 1,84 anos, e no pós-tratamento (T3), 22,94 ± 1,34 anos. Para a análise, foram utilizados traçados cefalométricos e modelos de estudo nas 3 fases. As variáveis nos 3 grupos, foram comparadas pela análise de variância a um critério ANOVA, considerando significativo o valor de P < 0,05. Os resultados mostraram uma grande estabilidade das variáveis cefalométricas, sendo estatisticamente diferentes somente a inclinação do primeiro molar e a posição ântero-posterior do lábio superior. A avaliação do índice PAR demonstrou que o tratamento com o aparelho Pendulum seguido pelo aparelho fixo, foi estável 5 anos pós-tratamento. Conclui-se que o tratamento da Classe II com o aparelho Pendulum e o aparelho fixo, foi estável em longo prazo. / There are, in the literature, several forms of treatment, supported by different therapeutic mechanisms for the correction of Class II malocclusion. However, a few works have studied the stability of Class II correction with the Pendulum appliance. Therefore, this study aimed at verifying the long-term stability (5 years) of a treatment with the Pendulum appliance followed by a fixed one. The sample consisted of 20 patients (14 females and 6 males). The average age at the beginning of the treatment (T1) was 14,02 ± 1,62 yrs, and at the end of the treatment (T2), 18,38 ± 1,84 yrs, and at the post-treatment (T3), 22,94 ± 1,34 yrs. Cephalometric measurements and cast models were used in the 3 phases and the variables for the 3 groups were compared by ANOVA variance analysis, by considering P<0,05, a significant value. The results show a great stability of the cephalometric variables, being statistically different, only the tipping of the 1st molar and the upper lip thickness. The PAR index assessment demonstrated that the treatment with the pendulum appliance, followed by a fixed one, was stable, 5 yrs post-treatment. It was concluded that the Class II treatment with the Pendulum appliance, followed by a fixed one, was more stable in the long term.
63

Application of Cerebellum Inspired Controllers to Balance Related Tasks

Mota, Ricardo Evora 20 December 2022 (has links)
No description available.
64

Método genealógico e modelos mistos na seleção de linhas segregantes de Capsicum baccatum var. pendulum.

OLIVEIRA, Hérica Santos de January 2013 (has links)
Capsicum baccatum var. pendulum chili peppers, known as ladies finger and cambuci, are greatly appreciated in Brazil, however, few studies related to genetic breeding improvement of this species are described. The aim of this study was to propose a new strategy of driving and selection of segregating lines C. baccatum var. pendulum to give sequence to the breeding program genetic of this species in UENF. Forty five lines F2:3 were obtained from individuals of the F2 generation from the cross between UENF 1616 and UENF 1732, using the pedigree method. The selection in F2 was made using the Mulamba Mock index and taking into consideration the traits of greater length, greater wall thickness, soluble solids content and higher dry fruit, important characters to meet both industry as the fruit in natura market. The lines F2:3 were evaluated under field conditions at a spacing of between 1.0 m and 1.2 m between plants rows with seven plants per line. The parents and one commercial genotype represented by BRS Mari were used as controls. The characteristics evaluated were days to flowering (DFF) and days to fruiting (DFR); plant height (PLH); canopy diameter (CAD); fruits number per plant (FNP); fruit fresh mass (FFM); fruit weight feature (FWF); fruit length (FRL); average fruit diameter (FDM); fruit pericarp thickness (FRT); soluble solid content (SSC); dry fruit mass (DFM) and dry matter content (DMC). The heritability estimate of the progeny mean was high magnitude ranging from 0.68 to 0.88 while the individual narrow sense heritability and additive heritability within the plot were of medium magnitude ranging from 0.23 to 0.46 and 0.15 to 0.43 respectively, except for FWF and MSF had values above 0.50 are considered high magnitude. The accuracy of selection was close to unity indicating high accuracy in selection for all traits. The selection of the 20 best lines for each characteristic was based on the ordering of rows in ascending order for the DFF, DFR, PLH, and CAD features in decreasing order for FNP, FFM, FWF, FRL, FDM, FRT, SSC, DFM and DMR, considering the values predicted additive genetic effect BLUP’S and the new improved average population. In order lines F2:3 were better than those obtained in selecting witnesses for the top positions for most traits. Multivariate analyzes were performed by UPGMA hierarchical clustering from individuals selected via higher estimates "BLUP" for FFM and FWF characteristics. After obtaining the groupings of individuals was possible to select these based on their desirable agronomic characteristics. The results obtained by the use of mixed via REML/BLUP and the multivariate analysis models can constitute a new proposal to select individuals with favorable agronomic traits for several generations in breeding programs autogamous species. / As pimentas da espécie Capsicum baccatum var. pendulum, conhecidas como pimenta dedo-de-moça e pimenta Cambuci, são bastante apreciadas no Brasil, porém, poucos trabalhos de melhoramento genético são descritos para essa espécie. O objetivo deste trabalho foi propor uma nova estratégia de condução e seleção de linhas segregantes de C. baccatum var. pendulum para dar sequência ao programa de melhoramento genético desta espécie em andamento na UENF. Quarenta e cinco linhas F2:3 foram obtidas de indivíduos da geração F2, oriunda do cruzamento entre UENF 1616 e UENF 1732, pelo método genealógico. A seleção em F2 foi feita utilizando o índice de Mulamba e Mock, levando-se em consideração as características de maior comprimento, maior espessura da polpa, maior teor de sólidos solúveis e maior massa seca do fruto, caracteres importantes para atender tanto à indústria quanto ao mercado de frutos in natura. As linhas F2:3 foram avaliadas em condições de campo com espaçamento de 1,0 m entre plantas e 1,2 m entre linhas, com sete plantas por linha. Os genitores e um genótipo comercial representado pela cultivar BRS Mari foram utilizados como testemunhas. As características avaliadas foram: dias até o florescimento (DFL) e frutificação (DFR); altura da planta (ALP); diâmetro da copa (DIC); número de frutos por planta (NFP); massa fresca de frutos (MFF); massa média de frutos (MMF); comprimento médio do fruto (CMF); diâmetro médio do fruto (DMF); espessura da polpa do fruto (EPF); teor de sólidos solúveis (TSS); massa seca do fruto (MSF); e teor de massa seca do fruto (TMS). A estimativa de herdabilidade da média da progênie foi de alta magnitude, variando de 0,68 a 0,88, enquanto a herdabilidade individual no sentido restrito e a herdabilidade aditiva dentro da parcela foram de média magnitude, variando de 0,23 a 0,46 e de 0,15 a 0,43, respectivamente, com exceção para MFF e MSF, que obtiveram valores acima de 0,50, sendo consideradas de alta magnitude. A acurácia de seleção foi próxima à unidade, indicando alta precisão na seleção para todas as características avaliadas. A seleção das 20 melhores linhas, para cada característica, foi feita com base no ordenamento de linhas de forma crescente para as características ALP, DIC, DFL, DFR e de forma decrescente para NFP, MMF, CMF, DMF, EPF, TSS, MFF, MSF e TMS, considerando os BLUPs dos valores de efeito genético aditivo predito e a nova média da população melhorada. No ordenamento, as linhas F2:3 foram melhores que as testemunhas, pois obtiveram na seleção as primeiras posições para a maioria das características avaliadas. Foram feitas análises multivariadas pelo agrupamento hierárquico UPGMA com indivíduos selecionados via maiores estimativas “BLUP” para as características MFF e MMF. Após a obtenção dos agrupamentos dos indivíduos, foi possível sua seleção com base em suas características agronômicas desejáveis. A utilização dos resultados obtidos pela metodologia dos modelos mistos e pela análise multivariada pode se constituir em uma nova proposta para selecionar indivíduos com características agronômicas favoráveis para avanço de gerações em programas de melhoramento de espécies autógamas.
65

Σχεδίαση και αξιολόγηση ακολουθίας διδακτικών ενοτήτων στα πλαίσια της καινοτομικής και εποικοδομητικής αντίληψης για το αναλυτικό πρόγραμμα φυσικών επιστημών : η περίπτωση της διδασκαλίας του εκκρεμούς στο γυμνάσιο

Δόσης, Σωτήρης 26 August 2014 (has links)
Στόχος της παρούσας διατριβής είναι η σχεδίαση και η αξιολόγηση μιας διδακτικής ακολουθίας για την κίνηση του απλού εκκρεμούς, στα πλαίσια της καινοτομικής και εποικοδομητικής αντίληψης για το αναλυτικό πρόγραμμα Φυσικών Επιστημών. Πρόκειται για έρευνα εφικτότητας η οποία διενεργείται σε τρία επίπεδα: της ανάλυσης, του σχεδιασμού και της εφαρμογής. Το επίπεδο ανάλυσης περιλαμβάνει την επιστημολογική ανάλυση του Γαλιλαϊκού πλαισίου μελέτης της κίνησης του απλού εκκρεμούς, την ανάλυση των νοητικών παραστάσεων των μαθητών για την κίνηση του απλού εκκρεμούς και την ανάλυση των απαιτήσεων της καινοτομικής και εποικοδομητικής αντίληψης για το αναλυτικό πρόγραμμα Φυσικών Επιστημών. Το επίπεδο σχεδιασμού περιλαμβάνει τη διατύπωση των διδακτικών στόχων και τη διαμόρφωση του περιεχομένου της διδακτικής ακολουθίας. Δομικά χαρακτηριστικά της ακολουθίας συνιστούν (α) η πολιτισμική επιλογή του τεχνολογικού πλαισίου λειτουργίας του ρολογιού-εκκρεμούς, (β) η εννοιολογική επιλογή της Γαλιλαϊκής προσέγγισης της μελέτης του απλού εκκρεμούς και (γ) η μεθοδολογική επιλογή της σχολικής εκδοχής της υποθετικο -παραγωγικής προσέγγισης της επιστημονικής γνώσης. Η προτεινόμενη ακολουθία απαρτίζεται από τέσσερις διδακτικές ενότητες και υλοποιείται μέσω δραστηριοτήτων - προβλημάτων, οι οποίες βασίζονται σε μετασχηματισμένο ή αυθεντικό υλικό προερχόμενο από την Ιστορία της Επιστήμης. Το επίπεδο εφαρμογής περιλαμβάνει την πειραματική εφαρμογή της διδακτικής ακολουθίας σε 36 μαθητές της Γ΄ Γυμνασίου και την αξιολόγηση της γνωστικής προόδου που υποθέτουμε ότι θα σημειώσουν. Χρησιμοποιείται η τεχνική του ερωτηματολογίου για να ανιχνευθούν οι νοητικές παραστάσεις των μαθητών πριν και μετά τη συμμετοχή τους στην εφαρμογή του προγράμματος. Η ανάλυση των δεδομένων πραγματοποιείται σε τρία επίπεδα. Στο πρώτο επίπεδο καταδεικνύεται η θετική συμβολή των δραστηριοτήτων της διδακτικής ακολουθίας στη μετακίνηση των απαντήσεων των μαθητών προς την κατεύθυνση της αποδεκτής σχολικής γνώσης για τη κίνηση του εκκρεμούς. Στο δεύτερο επίπεδο καταδεικνύεται η συνολική σημαντική γνωστική πρόοδος των μαθητών στις τρεις συνιστώσες της επιστημονικής γνώσης, την πολιτισμική, την εννοιολογική και τη μεθοδολογική. Τέλος, στο τρίτο επίπεδο καταδεικνύεται η θετική συμβολή της διδακτικής ακολουθίας στη συγκρότηση ομάδων μαθητών που χρησιμοποιούν με επαρκή και συνεκτικό τρόπο τόσο την εννοιολογική όσο και τη μεθοδολογική συνιστώσα της επιστημονικής γνώσης. / The aim of this thesis is the design and evaluation of a teaching sequence for the motion of the simple pendulum, under the innovative and constructive approach of the science curriculum. This study belongs to the ‘feasibility’ research current and was carried out at three levels: analysis, design and implementation. The level of analysis involves the analysis of Galilean epistemological framework about the motion of the pendulum, the analysis of mental representations of students about the motion of the simple pendulum and the analysis of the requirements of innovative and constructive approaches for the science curriculum. The level of design includes the formulation of learning objectives and the content development of the teaching sequence. The structural features of the sequence concern (a) the cultural dimension of scientific knowledge (the relationship between the simple pendulum and the timekeeping problem), (b) the conceptual dimension of scientific knowledge (a Galilean semi-quantitative approach of the isochronal motion of the simple pendulum) and (c) the methodological dimension of scientific knowledge (a hypothetico-deductive approach of the relation between the period of the simple pendulum, its string length and its gravitational acceleration) The proposed sequence is composed of four modules and is implemented through problem – solving activities, which are based on transformed or authentic material from the History of Science. The application level includes the experimental implementation of the teaching sequence to 36 students aged 14-15 y.o. and the evaluation of their cognitive progress that we assume took place during the teaching. A questionnaire is used to detect mental representations of students before and after having participated in the teaching intervention. Data analysis was carried out on three levels. The first level shows the positive contribution of the activities of the teaching sequence to a transformation of student responses towards the acceptable scientific school knowledge about the motion of the simple pendulum. The second level shows the overall significant cognitive progress of students in the three components of scientific knowledge, cultural, conceptual and methodological. Finally, the third level shows the positive contribution of the teaching sequence in the formation of groups of pupils using in an efficient and coherent manner both conceptual and methodological aspects of scientific knowledge.
66

Caracterização físico-química e de compostos funcionais de pimenta Dedo-de-Moça BRS Mari em função do estádio de maturação e tempo de armazenamento / Characterization physics, chemistry and functional compounds of Dedo-de-Moça BRS Mari peppers in function of stages of maturaty and storage time

Soethe, Cristina 06 September 2013 (has links)
Made available in DSpace on 2016-12-08T16:44:46Z (GMT). No. of bitstreams: 1 PGPV13MA129.pdf: 769146 bytes, checksum: 325221488dc3eed07f936323f45bb010 (MD5) Previous issue date: 2013-09-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study was to determine the characteristics of quality and functional compounds of Dedo-de-Moça BRS Mari peppers at different stages of maturation and the optimal period to harvest fruits with higher sensory and nutraceutical quality and evaluate two types of polymeric packaging and cold storage on the physico-chemical and nutraceutical characteristics of the peppers. The pepper fruits were grown in the experimental field at Embrapa Hortaliças, Brasília - DF, 2012. In experiment 1, the peppers were evaluated at 20, 30, 40, 50, 60, 70 and 80 days after anthesis (DAA) regarding soluble solids (SS), titratable acidity (TA), color (h°, L* and C), chlorophyll a, b and total phenolic content and capsanthin antioxidant activity. In experiment 2, the fruits harvested at 80 DAA were also evaluated postharvest in two types of polymeric packaging (polyvinyl chloride - PVC, polyethylene terephthalate - PET). In this experiment, the fruits were stored at 10±1°C for 15 days and evaluated every three days. It was found that when evaluating the maturation stages, the SS content increased up to 70 DAA and TA obtained peaked at 50 DAA with a decrease in the later stages. Total chlorophyll a reduced to 60 DAA from then little change occurred until 80 DAA. Chlorophyll b was higher at 30 DAA after the values were lower. Hue angle (h°) and L* decreased to 60 DAA, indicating the change of external color of the fruit from green to red, with small changes in color up to 80 DAA. The total phenolic content increased up to 60 DAA from then small increases occurred up to 80 DAA. The percentage of antioxidant activity increased during maturation, and capsanthin content had increased to 70 DAA when the fruits were completely red. No difference was observed between the packages evaluated the characteristics evaluated. The storage time had no effect on the soluble solids content, the percentage of citric acid and SS/TA ratio of the BRS Mari peppers. However, there was decreased brightness and increased hue angle and chroma from the third day of storage, with little change until the end of the experiment. The phenolic content and antioxidant activity decreased percentage of the third day of storage, with a little variation from then until the end of the storage period. The content of capsanthin was not influenced by storage time. Therefore, the ideal stage for harvesting Dedo-de-Moça BRS Mari peppers, taking into consideration the sensory characteristics, is at 70 DAA, when the highest levels of capsanthin occur. Fruits harvested at maturity stage feature higher antioxidant capacity. Regardless of the type of packing, cold storage did not alter the palatability characteristics, but by the third day of storage had a negative influence on the appearance of the fruit, and reduced the phenolic composition and the percentage of antioxidant activity / O objetivo deste trabalho foi determinar as características de qualidade e de compostos funcionais de pimenta Dedo-de-Moça BRS Mari em diferentes estádios de maturação e o período ideal de colheita dos frutos com maior qualidade sensorial e de compostos bioativos, bem como avaliar o efeito de dois tipos de embalagens poliméricas e o tempo de armazenamento refrigerado sobre as características físico-químicas e funcionais. As pimentas foram colhidas de plantas cultivadas no campo experimental da Embrapa Hortaliças, Brasília DF, 2012. No experimento 1 as pimentas foram avaliadas aos 20, 30, 40, 50, 60, 70 e 80 dias após a antese (DAA) quanto ao teor de sólidos solúveis (SS), acidez titulável (AT), coloração (h°, L* e C), clorofilas a, b e total, fenólicos totais, atividade antioxidante e teor de capsantina. No experimento 2, frutos colhidos aos 80 DAA foram avaliados quanto à conservação pós-colheita em dois tipos de embalagens poliméricas (policloreto de vinila PVC; polietileno tereftalato - PET). Neste experimento, os frutos foram armazenados a 10±1oC durante 15 dias e as avaliações realizadas a cada três dias. Verificou-se que ao avaliar os estádios de maturação, o teor de SS aumentou até 70 DAA e a AT obteve maior valor aos 50 DAA com decréscimo nos estádios posteriores. Clorofilas a e total reduziram até 60 DAA, quando a partir de então pouca variação ocorreu até 80 DAA. Clorofila b foi mais elevada aos 30 DAA, quando após os valores foram mais baixos. Ângulo hue (h°) e L* diminuíram até 60 DAA, indicando mudança da coloração externa dos frutos de verde para vermelho, com pequenas mudanças na coloração até 80 DAA. O conteúdo de fenólicos totais aumentou até 60 DAA, quando a partir de então pequenos aumentos ocorreram até 80 DAA. A porcentagem de atividade antioxidante aumentou durante a maturação, e o conteúdo de capsantina teve aumento até 70 DAA, momento em que os frutos estavam com a coloração externa totalmente vermelha. No experimento 2, não foi observada diferença significativa entre as embalagens avaliadas quanto às características avaliadas. O tempo de armazenamento não apresentou efeito sobre o teor de SS, AT e na relação SS/AT de pimentas BRS Mari . Todavia, diminuiu a luminosidade e aumentou o ângulo hue e o croma a partir do terceiro dia de armazenamento, com poucas alterações até o final do experimento. O teor de compostos fenólicos e porcentagem de atividade antioxidante diminuíram no terceiro dia de armazenamento, havendo a partir de então pouca variação até o final do período de armazenamento. O conteúdo de capsantina não foi influenciado pelo tempo de armazenamento. Portanto, o estádio ideal de colheita das pimentas Dedo-de-Moça BRS Mari , levando em consideração as características sensoriais, é aos 70 DAA, momento em que apresenta também maior conteúdo de capsantina. Frutos colhidos em estádio de maturação mais avançado apresentam maior capacidade antioxidante. Independente do tipo de embalagem, o tempo de armazenamento refrigerado não alterou as características de palatabilidade, mas até o terceiro dia de armazenamento influenciou negativamente na aparência dos frutos, reduziu a composição de fenólicos totais e a porcentagem de atividade antioxidante
67

Feedback Stabilization of Inverted Pendulum Models

Cox, Bruce 01 January 2005 (has links)
Many mechanical systems exhibit nonlinear movement and are subject to perturbations from a desired equilibrium state. These perturbations can greatly reduce the efficiency of the systems. It is therefore desirous to analyze the asymptotic stabilizability of an equilibrium solution of nonlinear systems; an excellent method of performing these analyses is through study of Jacobian linearization's and their properties. Two enlightening examples of nonlinear mechanical systems are the Simple Inverted Pendulum and the Inverted Pendulum on a Cart (PoC). These examples provide insight into both the feasibility and usability of Jacobian linearizations of nonlinear systems, as well as demonstrate the concepts of local stability, observability, controllability and detectability of linearized systems under varying parameters. Some examples of constant disturbances and effects are considered. The ultimate goal is to examine stabilizability, through both static and dynamic feedback controllers, of mechanical systems
68

Platform for ergonomic steering methods nvestigation of quot Segway-style quot balancing scooters

Zhou, Weiqian January 2008 (has links)
Segway has been a popular production as an alternative transporter since its invention at the end of 20th century. Millions of people like for its ergonomic design and high-tech elements. It is predicted to be an innovational product to change a person's life style. This thesis focuses on building a simple low cost, home-made Segway style scooter. This project uses two electric scooter motors, two 12V car batteries, one accelerometer and several microprocessors to build up the whole system. Significantly, this project also explains how to build a Brushed Direct Current (BDC) motor driver with a rated output power of more than 350W and the capability of coping with up to 120A transient peak current and up to 40A continuous current. Four-quadrant operation and eight modes of DC motor operation are discussed. A mathematical model of the Segway style scooter is also introduced in details. This including the modelling of a BDC motor, a two-wheeled inverted pendulum and their combination. The linearization of these models is used. At the end the linearized model is simulated in computer software.
69

Nonlinear control system of inverted pendulum based on input-output linearization

Maeda, Ken. January 2006 (has links)
Thesis (M.S.)--State University of New York at Binghamton, Thomas J. Watson School of Engineering and Applied Sciences, Electrical Engineering Department. / Includes bibliographical references.
70

Dynamics of a spin-1 BEC in the regime of a quantum inverted pendulum

Gerving, Corey Scott 03 April 2013 (has links)
The primary study of this thesis is the experimental realization of the non-equilibrium dynamics of a quantum inverted pendulum as examined in the collective spin dynamics of a spin-1 Bose-Einstein condensate. In order to compare experimental results with the simulation past the low depletion limit, current simulation techniques needed to be extended to model atomic loss. These extensions show that traditional measurements of the system evolution (e.g. measuring the mean and standard deviation of the evolving quantity) were insufficient in capturing the quantum nature of the evolution. It became necessary to look at higher order moments and cumulants of the distributions in order to capture the quantum fluctuations. Extending the implications of the loss model further, it is possible that the system evolves in a way previously unpredicted. Spin-mixing from a hyperbolic fixed point in the phase space and low noise atom counting form the core of the experiment to measure the evolution of the distributions of the spin populations. The evolution of the system is also compared to its classical analogue, the momentum-shortened inverted pendulum. The other experimental study in this thesis is mapping the mean-field phase space. The mean-field phase space consists of different energy contours that are divided into both phase-winding trajectories and closed orbits. These two regions are divided by a separatrix whose orbit has infinite period. Coherent states can be created fairly accurately within the phase space and allowed to evolve freely. The nature of their subsequent evolution provides the shape of the phase space orbit at that initial condition. From this analysis a prediction of the nature of the entire phase space is possible.

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