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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.
1

Towards controlling software architecture erosion through runtime conformance monitoring

de Silva, Lakshitha R. January 2014 (has links)
The software architecture of a system is often used to guide and constrain its implementation. While the code structure of an initial implementation is likely to conform to its intended architecture, its dynamic properties cannot always be fully checked until deployment. Routine maintenance and changing requirements can also lead to a deployed system deviating from this architecture over time. Dynamic architecture conformance checking plays an important part in ensuring that software architectures and corresponding implementations stay consistent with one another throughout the software lifecycle. However, runtime conformance checking strategies often force changes to the software, demand tight coupling between the monitoring framework and application, impact performance, require manual intervention, and lack flexibility and extensibility, affecting their viability in practice. This thesis presents a dynamic conformance checking framework called PANDArch framework, which aims to address these issues. PANDArch is designed to be automated, pluggable, non-intrusive, performance-centric, extensible and tolerant of incomplete specifications. The thesis describes the concept and design principles behind PANDArch, and its current implementation, which uses an architecture description language to specify architectures and Java as the target language. The framework is evaluated using three open source software products of different types. The results suggest that dynamic architectural conformance checking with the proposed features may be a viable option in practice.
2

Mecânica ventilatória, padrão ventilatório e custo metabólico da ventilação emTrachemys scripta e Chelonoidis carbonarius (Testudines: Cryptodira) / Ventilatory mechanics, ventilatory pattern and metabolic cost of ventilation in Trachemys scripta and Chelonoidis carbonarius (Testudines: Cryptodira)

Baú, Pedro Henrique Trevizan 04 March 2016 (has links)
Dentro da classe Reptilia, a ordem Testudines possui algumas características exclusivas, tais como a fusão das costelas e da coluna vertebral e a perda dos músculos intercostais, inviabilizando a ventilação costal. Além disso, as posições naturais que os Testudines exibem podem influenciar a mecânica ventilatória. O presente estudo teve como objetivo testar a influência do posicionamento do corpo sobre a mecânica ventilatória através da complacência estática e dinâmica e analisar através da respirometria aberta o padrão ventilatório e o custo metabólico da ventilação através da exposição em normóxia, hipóxia e hipercarbia em Trachemys scripta e Chelonoidis carbonarius. Os volumes pulmonares, complacência estática e dinâmica em C. carbonarius foram inferiores aos de T. scripta e outras espécies de Testudines já estudadas. Verificou-se também influência das posições sobre a mecânica ventilatória nas duas espécies, sendo a posição de membros e cabeça retraídos na carapaça apresentando os menores valores (p<0,05). Hipóxia e hipercarbia estimularam o aumento da ventilação nas duas espécies estudadas (p<0,05), sendo observadas maiores alterações da frequência ventilatória e volume corrente em C. carbonarius. Os valores de custo metabólico da ventilação foram baixos devido à uma diminuição no consumo de oxigênio em hipóxia e hipercarbia, indicando depressão metabólica em ambas as espécies ou então o método para calcular esse custo não ser ideal. Ao relacionar os dados de consumo de oxigênio com os de ventilação, verificou-se a possibilidade de shunt cardíaco esquerdo-direito. Será necessário calcular o trabalho mecânico da ventilação a fim de entender melhor a mecânica ventilatória nas duas espécies e posteriormente relacionar os dados de ventilação e custo metabólico da ventilação com os de trabalho mecânico. / Within the class of Reptilia, the order Testudines possesses some exclusive features such as merged ribs and spine and loss of intercostal muscles, preventing costal ventilation. Furthermore, the natural positions exhibited by Testudines, should influence ventilatory mechanics. The aim of this study was to test the influence of different body positions on ventilatory mechanics by measuring static and dynamic compliance and by using open respirometry to analyze the ventilatory pattern and metabolic cost of ventilation in normoxic, hypoxic and hypercarbic exposures in Trachemys scripta e Chelonoidis carbonarius. C. carbonarius showed the lowest values of lung volumes, static and dynamic compliance when compared to T. scripta as well as to other Testudines´s species. Natural positions significantly influenced ventilatory mechanics in both species, with the lowest values found in animals with legs and head retracted into the shell (p<0.05). Hypoxia and hypercarbia stimulated ventilation in both species, with alterations in frequency and tidal volume being greater in C. carbonarius. Estimated metabolic cost of ventilation was low because of a decrease in oxygen uptake during hypoxia and hypercarbia, indicating metabolic depression in both species or that the method used may not be ideal to calculate the metabolic cost of breathing. Relating oxygen uptake data with ventilation data, it may be possible that left-right cardiac shunting occurred. It will be necessary to calculate the mechanic work of breathing to better understand the ventilatory mechanics in both species and relate ventilation data and metabolic cost of ventilation with mechanical work of breathing.
3

Mecânica ventilatória, padrão ventilatório e custo metabólico da ventilação emTrachemys scripta e Chelonoidis carbonarius (Testudines: Cryptodira) / Ventilatory mechanics, ventilatory pattern and metabolic cost of ventilation in Trachemys scripta and Chelonoidis carbonarius (Testudines: Cryptodira)

Pedro Henrique Trevizan Baú 04 March 2016 (has links)
Dentro da classe Reptilia, a ordem Testudines possui algumas características exclusivas, tais como a fusão das costelas e da coluna vertebral e a perda dos músculos intercostais, inviabilizando a ventilação costal. Além disso, as posições naturais que os Testudines exibem podem influenciar a mecânica ventilatória. O presente estudo teve como objetivo testar a influência do posicionamento do corpo sobre a mecânica ventilatória através da complacência estática e dinâmica e analisar através da respirometria aberta o padrão ventilatório e o custo metabólico da ventilação através da exposição em normóxia, hipóxia e hipercarbia em Trachemys scripta e Chelonoidis carbonarius. Os volumes pulmonares, complacência estática e dinâmica em C. carbonarius foram inferiores aos de T. scripta e outras espécies de Testudines já estudadas. Verificou-se também influência das posições sobre a mecânica ventilatória nas duas espécies, sendo a posição de membros e cabeça retraídos na carapaça apresentando os menores valores (p<0,05). Hipóxia e hipercarbia estimularam o aumento da ventilação nas duas espécies estudadas (p<0,05), sendo observadas maiores alterações da frequência ventilatória e volume corrente em C. carbonarius. Os valores de custo metabólico da ventilação foram baixos devido à uma diminuição no consumo de oxigênio em hipóxia e hipercarbia, indicando depressão metabólica em ambas as espécies ou então o método para calcular esse custo não ser ideal. Ao relacionar os dados de consumo de oxigênio com os de ventilação, verificou-se a possibilidade de shunt cardíaco esquerdo-direito. Será necessário calcular o trabalho mecânico da ventilação a fim de entender melhor a mecânica ventilatória nas duas espécies e posteriormente relacionar os dados de ventilação e custo metabólico da ventilação com os de trabalho mecânico. / Within the class of Reptilia, the order Testudines possesses some exclusive features such as merged ribs and spine and loss of intercostal muscles, preventing costal ventilation. Furthermore, the natural positions exhibited by Testudines, should influence ventilatory mechanics. The aim of this study was to test the influence of different body positions on ventilatory mechanics by measuring static and dynamic compliance and by using open respirometry to analyze the ventilatory pattern and metabolic cost of ventilation in normoxic, hypoxic and hypercarbic exposures in Trachemys scripta e Chelonoidis carbonarius. C. carbonarius showed the lowest values of lung volumes, static and dynamic compliance when compared to T. scripta as well as to other Testudines´s species. Natural positions significantly influenced ventilatory mechanics in both species, with the lowest values found in animals with legs and head retracted into the shell (p<0.05). Hypoxia and hypercarbia stimulated ventilation in both species, with alterations in frequency and tidal volume being greater in C. carbonarius. Estimated metabolic cost of ventilation was low because of a decrease in oxygen uptake during hypoxia and hypercarbia, indicating metabolic depression in both species or that the method used may not be ideal to calculate the metabolic cost of breathing. Relating oxygen uptake data with ventilation data, it may be possible that left-right cardiac shunting occurred. It will be necessary to calculate the mechanic work of breathing to better understand the ventilatory mechanics in both species and relate ventilation data and metabolic cost of ventilation with mechanical work of breathing.
4

Dynamické vlastnosti obrobku při soustružení / Dynamic characteristic of the workpiece in turning

Nádvorník, Vít January 2016 (has links)
The contens of master thesis is theoretical analysis of vibrations during turning and possibillity to eliminate them, measure dynamic compliance and modal paramteters. The goal of experimental part is to determine the effect of material and type of clamping for three shafts at natural frequency, mode shape and dynamic compliance. Using these results we can optimized cutting parameters and to better overcome vibration during machining.
5

Nonlinear dynamics of cracked structures for non-destructive evaluation

Hiwarkar, Vikrant January 2010 (has links)
The power plant and aerospace industries have been facing a huge loss, due to structural failure. The structural failure occurs due to the presence of the crack in it. Hence, it becomes necessary to monitor the structural health under operating condition. Most of the techniques, for structural health monitoring are used for a specific purpose. Some of these techniques require structure dismantling, which is very much expensive and time consuming. So the vibration based structural health monitoring is advantageous, compared to other techniques. Most of the vibration based Structural Health Monitoring (SHM) approaches, use linear vibration theory. But, these linear vibration based procedures, have inherently low sensitivity to crack. Since crack introduces nonlinearities in the system, their merits in damage detection need to be investigated for SHM. In this thesis, the problem is focused on studying nonlinear dynamics of cracked structures for Structural Health Monitoring. For this, simulations and experiments are performed. The new procedure for the simulation is developed using Matlab-Simulink. It uses the numerical approximation for dynamic compliance operators and a nonlinear model of cracks contact faces interaction to study the dynamic behaviour of the cracked bar. Furthermore, the finite element model of the cracked cantilever bar with crack- tip plasticity is developed and the dynamic behaviour of the elasto-plastic bar is studied. Additionally, numerous experiments are performed to study the dynamics of cantilever bar with the fatigue crack in it. The results from Matlab-Simulink simulation shows the distribution of higher harmonics generated along the bar length, as a function of distance from the crack. In finite element simulation, comparison is made between the resonance frequency of cracked cantilever bar with and without crack-tip plasticity. It is found that, there is decrease in resonance frequency of the cracked bar with cracked tip plasticity, when compared with the resonance frequency of cracked bar without crack-tip plasticity. This reduction in resonance frequency is due to the crack-induced plasticity near the crack tip which affects the overall stiffness of bar. In experiments, the response is measured at four different points on the cracked cantilever bar at a given resonant frequency of excitation at lower and higher vibration amplitude. For lower vibration amplitude, it is found that the response obtained near the vicinity of the crack shows the presence of higher harmonics of resonant frequency, which disappears in the response obtained far away from the crack. For higher vibration amplitude, it is found that the response obtained near the vicinity of the crack shows the presence of higher harmonics along with the low frequency component. This low frequency component causes modulation, which leads to the generation of side band frequencies near the resonant frequency. The occurrence of low frequency component and side band frequencies is due to the vibro-impact behaviour of crack. The amplitude of these side band frequencies and higher harmonics are reduced in the response obtained far away from the crack. This indicates that crack-induced nonlinearity has a localized effect on the dynamics of bar. It is also observed that the magnitude of low frequency component is proportional to the magnitude of resonant frequency of excitation. This indicates that crack behaves like a signal modulator, detector of low frequency component and amplifier as the magnitude of low frequency component is proportional to the magnitude of resonant frequency excitation. From the Matlab-Simulink simulation and experimental results, it is concluded that crackinduced nonlinearity affects the dynamic behaviour of the cracked bar significantly, which will be effective in structural health monitoring. Keywords: vibro-impact, crack, dynamic compliance, harmonics, modulator, detector, amplifier, crack-tip plasticity, resonance frequency, structural health monitoring.
6

Auswirkungen der Ultrafiltration auf die Lungenfunktion bei Kindern nach Korrektur eines angeborenen Herzfehlers

Richter, Jost Wigand 14 December 2001 (has links)
Das mit dem kardiopulmonalen Bypass assoziierte kapilläre Leck bei Operationen am offenen Herzen führt zu einem Anstieg des totalen Wassergehalts des Körpers, wobei es vor allem zu einer pulmonalen sowie myokardialen Ödementwicklung kommt. Mit der von Naik, Knight und Elliott (1991) hinsichtlich Filterposition und Filtrationszeitpunkt beschriebenen modifizierten Form der Ultrafiltration unmittelbar nach Abgang vom Bypass konnte eine markante Reduzierung der mit dem Bypass assoziierten Flüssigkeitsakkumulation sowie eine unmittelbare Verbesserung der hämodynamischen Parameter (Herzindex, myokardiale Kontraktilität, verminderter postoperativer Verbrauch inotroper Substanzen) nachgewiesen werden. Ziel vorliegender Studie ist deshalb die Untersuchung der Auswirkung der modifizierten Ultrafiltration auf die Lungenfunktion. Für diese Studie wurden 37 Kinder (Alter 3 Tage bis 92 Monate, Gewicht 3,1 bis 21,3 kg) beobachtet, bei denen die operative Korrektur eines angeborenen Herzfehlers unter Einsatz der Herz-Lungen-Maschine (kardiopulmonaler Bypass mit extrakorporaler Membranoxygenierung) vorgenommen wurde. Bei 27 Kindern wurde nach Abgang von der Herz-Lungen-Maschine die modifizierte Hämofiltration durchgeführt, 10 Kinder dienten als Kontrollgruppe. Bei allen Patienten wurden vor Beginn sowie nach Abschluß des Einsatzes der Herz-Lungen-Maschine, nach der ca. zehn Minuten dauernden modifizierten Ultrafiltration bzw. bei der Kontrollgruppe zu einem vergleichbaren Zeitpunkt ca. zehn Minuten nach Entwöhnung vom kardiopulmonalen Bypass und nach einem weiteren Zeitraum von ca. zehn Minuten mittels dynamischer Lungenfunktionsmessung Parameter der Lungenmechanik (dynamische Compliance und Resistance) sowie Lungenfunktion (alveoloarterielle Sauerstoffdifferenz) bestimmt. Außerdem wurden hämodynamische (arterieller und zentralvenöser Blutdruck) und rheologische Veränderungen (Hämoglobin, Hämatokrit) aufgezeichnet. Bei der modifizierten Ultrafiltration zeigte sich unmittelbar nach Filtrationsende mit dem signifikanten Anstieg der Compliance um 13,9 % ein Effekt, der sich etwa 10 Minuten nach Filtrationsende noch weiter steigerte. Weiterhin konnte ein Abfall der alveoloarteriellen Sauerstoffdifferenz um insgesamt 29,2 % gemessen werden. Es ließ sich jedoch keine proportionale Abhängigkeit zwischen der Ultrafiltratmenge und der Verbesserung der Lungenfunktion nachweisen. Die von anderen Autoren unter modifizierter Ultrafiltration festgestellten Veränderungen der Hämodynamik, wie zum Beispiel der signifikante Anstieg des arteriellen Blutdruckes, oder der rheologischen Veränderungen, wie zum Beispiel ein Anstieg des Hämatokrit-Wertes, ließen sich bestätigen. Die Ergebnisse zeigen, daß durch die modifizierte Technik der Ultrafiltration eine unmittelbare Verbesserung der postoperativen Lungenfunktion erreicht werden kann. / The capillary leak, associated with cardiopulmonary bypass in open heart surgery, causes a rise of total body water resulting in tissue, especially in pulmonary and myocardial edema. The modified ultrafiltration is a new aproach to reduce these edemas, first described by Naik, Knight and Elliot in 1991. With the modification of the postition of the ultrafilter in the bypass circuit and the time of filtration in the first minutes after the patient has been weaned from bypass a significant reduction of the bypass associated fluid accumulation could be shown as well as an improvement of hemodynamics (heart index, myocardial contractility, reduced need of inotopic drugs). To investigate the influence of the modified ultrafiltration on the lung function is the objective of this study. In this study 37 children (aging from 3 days to 92 months, weighting from 3.1 to 21.3 kg) have been examined in cardiac surgery for moderate to severe congenital heart disease with the application of the cardiopulmonary bypass. The effect of modified ultrafiltration, which immediately started after being weaned from the cardiopulmonary bypass, was studied in 27 children, 10 children formed the controll population. In all patients alterations in pulmonary mechanics (dynamic compliance and resistance), in pulmonary function (alveolar-arterial difference of oxygen), in hemodynamics (arterial and central venous blood pressure, heart rate) and in blood values (hemoglobin, hematocrit) could be recorded at frequent intervals. The measurements were done before and after being weaned from bypass, after conclusion of the modified ultrafiltration respectively after a comparable intervall in the control group and about 10 minutes later before the closure of the chest was performed. After the modified ultrafiltration a significant increase of pulmonary compliance of about 13.9 % was observed, an effect, which was further amplified in the next 10 minutes. Furthermore a decrease of alveolar-arterial difference of oxygen of 29.2 % could be shown, but no correlation between the amount of ultrafiltrat and improvement of pulmonary function could be proved. Other findings like a significant increase of arterial blood pressure or an increase of the hematocrit, which were also described by other authors in previous studies, could be confirmed. The results indicate, that by using the modified technique of ultrafiltration an improvement of pulmonary function is achievable.
7

Avalia??o muscular respirat?ria: adapta??o do mano vacu?metro nacional para a avalia??o da press?o inspirat?ria nasal e n?vel de intensidade da ventila??o volunt?ria m?xima em sujeitos saud?veis

Severino, Fernanda Gadelha 18 May 2010 (has links)
Made available in DSpace on 2014-12-17T15:16:09Z (GMT). No. of bitstreams: 1 FernandaG_DISSERT.pdf: 1166474 bytes, checksum: 42a23625c719bb1096b1c812ac17e8f4 (MD5) Previous issue date: 2010-05-18 / The clinical importance of evaluating the respiratory muscles with a variety of tests has been proposed by several studies, once that the combination of several tests would allow a better diagnosis and therefore, a better clinical follow of disorders of the respiratory muscles. This study aimed to evaluate the feasibility of adapting a national electronic manovacuometer to measure the nasal inspiratory pressure (study 1) and analyze the level of load intensity of maximum voluntary ventilation, as well as the variables that may influence this maneuver in healthy subjects (study 2). We studied 20 healthy subjects by a random evaluation of two measures of SNIP in different equipments: a national and an imported. In study 2 it was analyzed the intensity of the load of MVV test, change in pressure developed during the maneuver, the possible differences between genders, and the correlations between the flow developed in the test and the result of MVV. In study 1 it was found the average for both measures of nasal inspiratory pressures: 125 ? 42.4 cmH2O for the imported equipment and 131.7 ? 28.7 cmH2O for the national one. Pearson analysis showed a significant correlation between the average, with a coefficient r = 0.63. The average values showed no significant differences evaluated by paired t test (p> 0.05). In the Bland-Altman analysis it was found a BIAS = 7 cmH2O, SD 32.9 and a confidence interval of - 57.5 cmH2O up to 71.5 cmH2O. In the second study it was found significant differences between the genders in the air volume moved, being higher in males 150.9 ? 13.1 l / min vs 118.5 ? 15.7 L / min for (p = 0.0002, 95% CI 44.85 to 20:05). Regarding the inspiratory and expiratory loading, they were significantly higher in men than in women, peak inspiratory pressure (34.7 ? 5.3 cmH2O vs 19.5 ? 4.2 cmH2O, 95% CI - 18.0 to -12.3, p <0.0001), peak expiratory (33.8 vs. 23.1 ? 5.9 cmH2O ? 5.4 cmH2O, 95% CI -17.1 to - 4.6, p <0.0001), and the delta pressure (59.7 ? 10 cmH2O vs 36.8 ? 8.3 cmH2O, 95% CI 14.5 to 31.2, p <0.0002). The Pearson correlation showed that the flow generated by the maneuver is strongly correlated with the delta-expiratory pressure / inspiratory (r2= 0.83,R = 0.91, 95%IC 0.72 a 0.97 e p< 0.0001).Through these results we suggest that the national electronic manovacuometer is feasible and safe to perform the sniff test in healthy subjects. For the MVV, there are differences between the genders in the intensity of pressure developed during the maneuver. We found a load intensity considered low during the MVV, and found a strong correlation between the flow generated in the test and the delta pressure expiratory / inspiratory / A import?ncia clinica de avaliar os m?sculos respirat?rios com uma variedade de testes vem sendo proposta por diversos trabalhos, pois a combina??o de v?rios testes possibilitaria um melhor diagn?stico e consequentemente um melhor seguimento cl?nico das disfun??es dos m?sculos respirat?rios. Este trabalho teve como objetivo avaliar a viabilidade da adapta??o do manovacu?metro nacional eletr?nico para a realiza??o da medida de press?o inspirat?ria nasal (estudo 1) e analisar o n?vel de intensidade de carga da ventila??o volunt?ria m?xima, assim como as vari?veis que possam influenciar a manobra em sujeitos saud?veis (estudo 2). Foram estudados 20 sujeitos saud?veis atrav?s da avalia??o aleat?ria de duas medidas de SNIP em equipamentos diferentes: um nacional e outro importado. No estudo 2 foi analisado a intensidade da carga do teste da ventila??o volunt?ria m?xima(VVM), a varia??o de press?o desenvolvida durante manobra, as poss?veis diferen?as entre g?neros, e as correla??es entre o fluxo desenvolvido no teste e o resultado da VVM. No estudo 1 as m?dias encontradas durante as duas medidas das press?es nasais foram de 125 ? 42,4 cmH2O para o aparelho importado e de 131,7 ? 28,7 cmH2O para o nacional. A an?lise de Pearson demonstrou uma correla??o significativa entre as m?dias com um coeficiente r=0.63. Os valores m?dios n?o apresentaram diferen?as significativas avaliadas pelo teste t pareado (p>0,05).Na an?lise de Bland-Altman foi encontrado um BIAS igual a 7 cmH2O, desvio padr?o 32,9 e um intervalo de confian?a de - 57,5cmH2O at? 71,5 cmH2O. No estudo 2 foi encontrada diferen?a significativa entre os g?neros para o volume de ar deslocado maior em homens 150.9 ? 13.1 l/mim vs 118.5 ? 15.7 L/mim para (p= 0.0002, IC95% 20.05 ? 44.85). Em rela??o carga inspirat?ria e expirat?ria foram significativamente maiores em homens que nas mulheres: pico inspirat?rio (34.7 ? 5.3 cmH2O vs 19.5 ? 4.2 cmH2O, IC95% - 18.0 a -12.3, p< 0.0001), pico expirat?rio (33.8 ? 5.9 cmH2O vs 23.1 ? 5.4 cmH2O, IC95% -17.1 a - 4.6, p< 0.0001), assim como o delta de press?o (59.7 ? 10 cmH2O vs 36.8 ? 8.3 cmH2O, IC95% 14.5 a 31.2 , p< 0.0002). A correla??o de Pearson mostrou que o fluxo gerado pela manobra est? fortemente correlacionado com o delta de press?o expirat?ria/inspirat?ria (r2= 0.83,R = 0.91, (95%IC 0.72 a 0.97 e p< 0.0001). Atrav?s dos resultados encontrados podemos sugerir que o manovacu?metro eletr?nico nacional ? vi?vel e seguro para realiza??o do sniff teste em sujeitos saud?veis. Em rela??o a VVM, existem diferen?as entre os g?neros na intensidade de press?o desenvolvida durante a VVM, a uma intensidade de carga durante a VVM foi considerada baixa assim como foi encontrada uma forte correla??o entre o fluxo gerado no teste e o delta de press?o expirat?rio/inspirat?rio

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