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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.
31

Využití R-materiálu v asfaltových směsích s pojivem typu PMB / Use of R-material in asphalt mixtures with PMB type binder

Navrátilová, Pavlína Unknown Date (has links)
The diploma thesis is focused on the use of R-material in asphalt mixtures with a PMB type binder. The work is divided into a theoretical part and a practical part. The theoretical part describes the acquisition of R-material by road milling, the use of R-material, the binder used in the practical part of the work and the types of recycling. The practical part deals with the design of four types of asphalt mixtures with different content of R-material in the asphalt mixture. It also deals with the description of functional tests of asphalt mixtures and the results of these tests.
32

Variabilidade ventilatória durante exercício dinâmico em indivíduos saudáveis e com insuficiência cardíaca / Ventilatory variability during exercise in individuals with heart failure and healthy ones

Renata Rodrigues Teixeira de Castro 06 December 2010 (has links)
A presença de ventilação periódica durante o exercício confere pior prognóstico a pacientes com insuficiência cardíaca. Existem divergências quanto aos critérios para identificação deste fenômeno. Além disso, a interpretação dicotômica (presença ou ausência) quanto a este fenômeno dificulta a estratificação de risco mais detalhada dos pacientes com insuficiência cardíaca. Desta forma, esta tese avalia a utilização de técnicas estabelecidas para análise de variabilidade de sinais para quantificar as oscilações ventilatórias que ocorrem durante o teste cardiopulmonar de exercício, em indivíduos saudáveis, atletas e com insuficiência cardíaca. Um protocolo mais curto para realização de teste cardiopulmonar de exercício em cicloergômetro de braço foi proposto e validado. Tal protocolo foi utilizado em estudo posterior, onde se comprovou que, apesar dos tempos respiratórios não serem influenciados pelo tipo de exercício realizado, a variabilidade ventilatória é maior durante a realização de exercício dinâmico com membros superiores do que com membros inferiores. A capacidade aeróbica de indivíduos sadios também influencia a variabilidade ventilatória durante o teste cardiopulmonar de exercício. Isto foi comprovado pela menor variabilidade ventilatória no domínio do tempo em atletas do que sedentários durante exercício. A análise destes voluntários com o método da análise dos componentes principais revelou que em atletas a variabilidade do volume corrente é a principal responsável pela variabilidade da ventilação-minuto durante o exercício, ao passo que em sedentários a variabilidade da freqüência respiratória apresenta-se como principal responsável por tais variações. Em estudo randomizado e controlado comprovamos que, mesmo indivíduos sadios apresentam redução da variabilidade ventilatória ao exercício após 12 semanas de treinamento físico. Comprovamos que a reabilitação cardíaca reverteu a ocorrência de ventilação periódica em um paciente com insuficiência cardíaca e, finalmente, encontramos que a variabilidade ventilatória correlaciona-se inversamente com a fração de ejeção ventricular esquerda em pacientes com insuficiência cardíaca. Estudos futuros deverão analisar o poder prognóstico da variabilidade ventilatória nestes pacientes. / Exercise periodic breathing confers a bad prognosis in patients with heart failure. There is no agreement among proposed criteria to diagnose exercise periodic breathing. The dichotomic interpretation (presence or absence) when diagnosing this phenomenon impairs a more detailed risk stratification in heart failure. Thus, this thesis evaluates the use of established signal variability techniques to quantify ventilatory oscillations during cardiopulmonary exercise test, in healthy individuals, athletes and patients with heart failure. A short protocol used to perform cardiopulmonary exercise test in arm crank was proposes and validated. This protocol was used in the next study, which found that, although timing of breathing was not altered by exercise type, ventilatory variability was greater during arm dynamic exercise when compared to leg exercise. Aerobic capacity of healthy individuals also influences ventilatory variability during cardiopulmonary exercise test. This was proven by the lower time-domain ventilatory variability in athletes when compared to sedentary individuals. The evaluation of these individuals with principal components analysis showed that tidal volume variability is the principal component o minute-ventilation variability in athletes, whilst in sedentary men, respiratory frequency variability is the responsible for minute-ventilation variability. In a randomized controlled study we have found that even healthy individuals reduce their exercise ventilatory variability after 12 weeks exercise training. We have shown that cardiac rehabilitation reverted exercise periodical breathing in a patient with heart failure and, finally, found that exercise ventilatory variability inversely correlates to left ventricle ejection fraction in patients with heart failure. Future studies should evaluate the prognostic value of ventilatory variability in these patients.
33

Variabilidade ventilatória durante exercício dinâmico em indivíduos saudáveis e com insuficiência cardíaca / Ventilatory variability during exercise in individuals with heart failure and healthy ones

Renata Rodrigues Teixeira de Castro 06 December 2010 (has links)
A presença de ventilação periódica durante o exercício confere pior prognóstico a pacientes com insuficiência cardíaca. Existem divergências quanto aos critérios para identificação deste fenômeno. Além disso, a interpretação dicotômica (presença ou ausência) quanto a este fenômeno dificulta a estratificação de risco mais detalhada dos pacientes com insuficiência cardíaca. Desta forma, esta tese avalia a utilização de técnicas estabelecidas para análise de variabilidade de sinais para quantificar as oscilações ventilatórias que ocorrem durante o teste cardiopulmonar de exercício, em indivíduos saudáveis, atletas e com insuficiência cardíaca. Um protocolo mais curto para realização de teste cardiopulmonar de exercício em cicloergômetro de braço foi proposto e validado. Tal protocolo foi utilizado em estudo posterior, onde se comprovou que, apesar dos tempos respiratórios não serem influenciados pelo tipo de exercício realizado, a variabilidade ventilatória é maior durante a realização de exercício dinâmico com membros superiores do que com membros inferiores. A capacidade aeróbica de indivíduos sadios também influencia a variabilidade ventilatória durante o teste cardiopulmonar de exercício. Isto foi comprovado pela menor variabilidade ventilatória no domínio do tempo em atletas do que sedentários durante exercício. A análise destes voluntários com o método da análise dos componentes principais revelou que em atletas a variabilidade do volume corrente é a principal responsável pela variabilidade da ventilação-minuto durante o exercício, ao passo que em sedentários a variabilidade da freqüência respiratória apresenta-se como principal responsável por tais variações. Em estudo randomizado e controlado comprovamos que, mesmo indivíduos sadios apresentam redução da variabilidade ventilatória ao exercício após 12 semanas de treinamento físico. Comprovamos que a reabilitação cardíaca reverteu a ocorrência de ventilação periódica em um paciente com insuficiência cardíaca e, finalmente, encontramos que a variabilidade ventilatória correlaciona-se inversamente com a fração de ejeção ventricular esquerda em pacientes com insuficiência cardíaca. Estudos futuros deverão analisar o poder prognóstico da variabilidade ventilatória nestes pacientes. / Exercise periodic breathing confers a bad prognosis in patients with heart failure. There is no agreement among proposed criteria to diagnose exercise periodic breathing. The dichotomic interpretation (presence or absence) when diagnosing this phenomenon impairs a more detailed risk stratification in heart failure. Thus, this thesis evaluates the use of established signal variability techniques to quantify ventilatory oscillations during cardiopulmonary exercise test, in healthy individuals, athletes and patients with heart failure. A short protocol used to perform cardiopulmonary exercise test in arm crank was proposes and validated. This protocol was used in the next study, which found that, although timing of breathing was not altered by exercise type, ventilatory variability was greater during arm dynamic exercise when compared to leg exercise. Aerobic capacity of healthy individuals also influences ventilatory variability during cardiopulmonary exercise test. This was proven by the lower time-domain ventilatory variability in athletes when compared to sedentary individuals. The evaluation of these individuals with principal components analysis showed that tidal volume variability is the principal component o minute-ventilation variability in athletes, whilst in sedentary men, respiratory frequency variability is the responsible for minute-ventilation variability. In a randomized controlled study we have found that even healthy individuals reduce their exercise ventilatory variability after 12 weeks exercise training. We have shown that cardiac rehabilitation reverted exercise periodical breathing in a patient with heart failure and, finally, found that exercise ventilatory variability inversely correlates to left ventricle ejection fraction in patients with heart failure. Future studies should evaluate the prognostic value of ventilatory variability in these patients.
34

Vlastnosti asfaltových směsí typu SMA s R-materiálem / Properties of asphalt mixtures of SMA-type with RAP

Acuna Subia, Luis Carlos January 2018 (has links)
The aim of the diploma thesis is to verify and compare the properties of bituminous stone mastic asphalt, namely SMA 11S with modified PMB 45 / 80-55 asphalt binder or 50/70 road bitumen binder with rubber granulate. Comparison of properties is performed using functional tests. The thesis is divided into the theoretical and practical part. The theoretical part deals with the familiarization with the use of the SMA mixture, the selected concepts concerning recycling of non-leveled roads are described and described. Attention is paid especially to the recycling of roads in the Czech Republic with an emphasis on hot recycling on the incinerator, which allows increased dosing of Reclaimed Asphalt into asphalt mixtures. In the practical part, the results of the functional tests of the SMA 11S mixture, which have been taken from the test section, are processed and evaluated.
35

Využití pěnoasfaltu v asfaltových směsích / Usage of foam bitumens in asphalt mixtures

Venclíková, Michaela January 2018 (has links)
In this diploma thesis there are described the issues use of foamed bitumen as binder in asphalt mixtures. The thesis is divided into two parts, theoretical and practical. The aim of theoretical part was to elaborate an overview of technologies, which allow to reduce the temperature during the production and laying of asphalt mixtures. The aim of the practical part was to compare the selected empirical and functional parameters of two types of asphalt mixtures produced in two variants, with hot bitumen and foamed bitumen. Attention was paid mainly to stiffness and low temperature parameters.
36

Využití technologie pěnoasfaltu / Usage of foam bitumen technology

Machel, Ondřej January 2019 (has links)
The diploma thesis deals with the production of warm mix asphalts, using the foam bitumen technology. The thesis is divided into theoretical and practical part. The theoretical part is focused on the basic division of roadway constructions, particularly on warm mix asphalts. The aim of the practical part was to find out whether the produced asphalt mixture retains its functional properties when the operating temperature is reduced. For this purpose, two asphalt mixtures of the ACO 11+ type at operating temperature of 150 °C and reduced operating temperature of 130 °C were made. Functional tests and empirical and functional tests were carried out on the produced asphalt mixtures and the extracted bitumen binders respectively. In the conclusion of the thesis, the results of the tests are mutually compared.
37

Využití R-materiálu v krytových vrstvách vozovek / Usage of recycled material in asphalt surface layers

Malá, Markéta January 2016 (has links)
Diploma thesis deals with adding R - material to the wearing asphalt courses, specifically to the SMA 11S. It has two parts – theoretical and practical. The theoretical part describes using R - material in the recycling of roads, different types of recycling and how is this problem handled in the Czech Republic, the practical part deals with the design of three kinds of asphalt mixtures with different added ratios of R – material, describing empirical and functional tests on the bitumen binder and the designed asphalt mixtures and the results of those tests.
38

Využití R - materiálu v asfaltových kobercích mastixových / Usage of recycled material in stone mastic asphalts

Slavíček, Michal January 2017 (has links)
This diploma thesis deals with the designs of asphalt mixtures for the wearing asphalt courses, specifically for the SMA 11S with an added 30 % and 50 % RAP (reclaimed asphalt pavement), this material was reclaimed from the wearing asphalt course type SMA. The thesis is divided into two parts. The first part is theoretical and it deals with the recycling of asphalt roads and adding RAP to the new asphalt mixures for the roads. The second part is practical. It deals with the design itself. Two types of SMA were designed, first with a 30 % RAP and second with a 50 % RAP. In those mixtures functional tests of asphalt mixtures were made.The results were compared to the asphalt mixture with 0 % of RAP and with the mixture with 30 % of RAP reclaimed from the wearing, binder and base course together. The results are summed up in the conclusion.
39

Ověření funkce bezkontaktního snímače hladiny paliva v palivové nádrži / Testing and calibration of fuel level gauge

HAIKL, Petr January 2013 (has links)
This work inkluse measurement principles for measuring liquid level in tanks with a focus on fuel. Are described most frequently used types of liquid level sensors, focusing on fuel. The work inkluse design chosen technical solutions fuel level sensor and its technical implementation, including the technical implementation and verification of its functionality and calibration.

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