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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.
211

Hodnocení kardiorespirační zdatnosti sportovců a obézních pacientů pomocí spiroergometrie (Oxycon) / Evaluation of cardiorespiratory capacity of sportsmen and obese patients measured by spiroergometry (Oxycon)

Kieu Thi, Thanh Hai January 2011 (has links)
The objective of this thesis is to evaluate the cardiorespiratory fitness of sportsmen and obese patients through the medium of spiroergometry on cycloergometer by virtue of the analyzer of exhaled gas (Oxycon). Its advantage is that the measurement takes place "on- line", therefore it allows prompt monitoring of measured spiroergometric parameters directly on screen of computer that forms part of the analyzer. The spiroergometry is a method of determining the cardiorespiratory fitness through the medium of analyzer of exhaled gas in order to state the physical fitness. For statistical evaluation of differences in values of spiroergometric indicators between these two observed groups of patients I used the Student's unpaired T-test. The theoretical part contains an introduction into the issue of obesity, obesity epidemiology, history, aetiology and health risks of this disease, classification, diagnostics, treatment, and recommendations and advices for patients. Furthermore it contains terms as sports medicine, influence of motional activity on human organism, cardiorespiratory fitness, spiroergometry methodology, and spiroergometric parameters. The practical part contains a description of spiroergometric measuring process at the Institute of Sports Medicine at the 1st Faculty of Medicine of the...
212

Shape Optimization Of A Cylilndrical-Electrode Structure To Mimic The Orbitrap

Ovhal, Ajay Ashok 08 1900 (has links) (PDF)
The Orbitrap is a mass analyzer that employs an electrostatic field to confine ions. The mass of an ion is determined from the frequency of its axial oscillations in the Orbitrap. The Orbitrap has high resolving power and accuracy. However, the electrodes of the Orbitrap have complicated curved shapes. As a consequence the Orbitrap is not easy to miniaturize. In this thesis we have proposed a class of easily machinable cylindrical-electrode structures to mimic the behavior of an Orbitrap. The proposed structure consists of a single cylinder and many coaxial equally spaced thick rings. A detailed numerical simulation of the cylindrical-electrode structure reveals that axial ion oscillations in it have many spurious frequency components in addition to the dominant frequency component. We have carried out a systematic shape optimization that adjusts the dimensions of the structure to minimize the amplitudes of the spurious frequency components of ion motion in the axial direction. The performance of the optimized structure was found to rival that of a practical Orbitrap.
213

The environment qualities evaluation of a degraded area in recuperation and the drying process of a Brazilian soil using nonconventional methods at micrometric scale / A avaliação da qualidade ambiental de uma área degradada em recuperação e o processo de secagem de um solo brasileiro utilizando métodos não-convencionais em escala micrométrica

Chien Ling Tseng 03 April 2017 (has links)
Soil is a fundamental resource in the environment, its sustainable use is vital to food supply and, consequently, life continuity on the Earth. However, the currently status of this resource in the world is critical and, therefore, the need of soil recovery measures and methods to evaluate it is urgent. The aim of this study is to provide a holistic evaluation about soil architecture at different recovery states, as well as its interaction with fluid in the environment by using nonconventional methods. It was organized a tool package that allows to analyze soil physical at geometric, morphometric and energy scope, to show in a more efficient way, which physical parameters indicate the physical and environmental quality. Subsequently, this package was applied to the study of six types of managements in different stages of development by using of physical parameter derived from the package; It was also analyzed the efficiency of recovery techniques under different perspectives. In addition, the soil-water dynamic was evaluated in a particular condition by using the same tools, offering knowledge about this interaction in the environment along the time. Finally, it is expected that this work can bring new insight on preservation and recovery of this environmental resource. / O solo é um recurso fundamental no meio ambiente, seu uso sustentável é vital para prover alimentos e consequentemente a continuidade da vida na Terra. No entanto, estado atual desse recurso no mundo encontra-se em condição crítica, logo as medidas de recuperação devem ser adotadas urgentemente, consequentemente a necessidade de métodos adequados para avaliação dessas medidas. O objetivo desse estudo é proporcionar uma avaliação holística sobre a arquitetura do solo em diferentes estados de recuperação, assim como sua interação com fluido no meio ambiente utilizando métodos não convencionais. Logo, foi organizado um pacote de ferramentas que permitam analisar a física solo no âmbito de geometria, morfometria e energia, proporcionando parâmetros físicos que indicam a qualidade física e ambiental; Em seguida esse pacote foi aplicado no estudo de seis tipos de manejos com diferentes estágios de desenvolvimento, envolvendo os parâmetros físicos derivados do pacote, mostrando assim a eficiência das técnicas de recuperação sob diferentes perspectivas; Assim foi realizado também a avaliação da dinâmica da água no solo em uma situação particular utilizando as mesmas ferramentas, proporcionando conhecimentos sobre o essa interação no meio ambiente ao longo do tempo. Finalmente, espera-se com esse trabalho novos olhares sobre esse recurso precioso no meio ambiente.
214

Caracterización y mejora genética de la berenjena (Solanum melongena) para compuestos bioactivos

Plazas Ávila, María de la O 31 March 2015 (has links)
Las frutas y hortalizas presentan compuestos bioactivos beneficiosos para la salud humana. El desarrollo de variedades con un mayor contenido en este tipo de compuestos es de interés, ya que contribuye a satisfacer una demanda creciente por parte de los consumidores por productos con propiedades funcionales. Dentro de las hortalizas, la berenjena (Solanum melongena) presenta una alta actividad antioxidante, fundamentalmente derivada de su alto contenido en polifenoles, y se ha demostrado que presenta efectos beneficiosos para la salud humana. Entre los compuestos fenólicos de la berenjena destaca el ácido clorogénico, ya que se trata del más abundante en este cultivo y presenta múltiples propiedades beneficiosas para la salud. Esta Tesis Doctoral trata de la caracterización y mejora de la berenjena para obtener información relevante y material vegetal para el desarrollo de variedades de berenjena con un mayor contenido en compuestos bioactivos, en particular polifenoles. Para ello utilizamos la variación intraespecífica e interespecífica. Por otra parte, en una mejora integral se debe tener en cuenta no solo el carácter a mejorar, sino también aquellos caracteres de interés para el éxito de una variedad, por lo que también hemos estudiado otros caracteres relacionados con el incremento del contenido en polifenoles, como puede ser el pardeamiento del fruto, y así como otros caracteres de interés general en mejora. En una primera parte de esta Tesis Doctoral nos centramos en el estudio de la diversidad en berenjena común y especies relacionadas para los caracteres objeto de esta tesis y también para caracteres de interés agronómico. El objetivo es evaluar la diversidad, identificar fuentes de variación y estudiar las relaciones entre caracteres. En un primer estudio, evaluamos una colección de variedades tradicionales de berenjena, en la cual hemos encontrado una alta diversidad para caracteres de calidad funcional y pardeamiento. En este estudio encontramos que el contenido en ácido clorogénico está correlacionado positivamente con la actividad antioxidante y que la correlación con el pardeamiento es baja, demostrando que es posible seleccionar variedades de berenjena con alto contenido en ácido clorogénico y pardeamiento moderado. También comprobamos que incluso con baja actividad polifenol oxidasa (PPO) se puede producir pardeamiento significativo, sugiriendo que la actividad PPO no es el factor limitante para el pardeamiento en la colección estudiada. Con objeto de ampliar la diversidad genética de la berenjena para la mejora de compuestos bioactivos y otros caracteres de importancia hemos estudiado la diversidad en una colección de berenjenas escarlata (S. aethiopicum) y gboma (S. macrocarpon). La caracterización morfológica mediante descriptores convencionales y herramientas fenómicas (Tomato Analyzer) nos ha permitido estudiar las relaciones entre los distintos grupos de cultivares y especies silvestres relacionadas y determinar que los complejos berenjena escarlata y gboma son hipervariables. En esta colección hemos estudiado también la actividad reductora y el contenido en ácido clorogénico, encontrado una enorme variabilidad. En general, la berenjena escarlata presenta contenidos relativamente bajos, mientras que la berenjena gboma, en particular su ancestro silvestre S. dasyphyllum, presentan valores muy elevados. También hemos comprobado en cultivos celulares de macrófagos que las variedades con mayor contenido en ácido clorogénico presentan una mayor inhibición de la producción de óxido nítrico (NO) indicando propiedades beneficiosas para la salud. En la segunda parte de la Tesis Doctoral hemos evaluado el interés de la hibridación interespecífica para la mejora de la berenjena, en particular para el contenido en compuestos bioactivos. Hemos obtenido dos familias, incluyendo retrocruzamientos, entre la berenjena común (S. melongena) por una parte y la berenjena escarlata cultivada (S. aethiopicum) y la especie silvestre S. incanum por otra. Los resultados muestran que la fertilidad de los materiales derivados de la hibridación entre S. melongena y S. aethiopicum es baja y que se obtiene una baja eficiencia en los retrocruzamientos hacia S. melongena. Además, el bajo contenido en polifenoles de S. aethiopicum se comporta como dominante. En cambio el retrocruzamiento hacia S. aethiopicum proporciona muchas plantas con mayores niveles de fertilidad. Sugerimos, por tanto, que S. melongena puede ser una fuente de variación para la mejora en contenido en polifenoles de la berenjena escarlata. La familia obtenida por hibridación interespecífica entre S. melongena y S. incanum mostró altos niveles de fertilidad y en el primer retrocruce hacia S. melongena se encuentran individuos morfológicamente similares a la Resumen berenjena cultivada. El estudio de los compuestos fenólicos mostró que S. incanum es una buena fuente de variación para la mejora de la berenjena común, con valores muy superiores a los de la especie cultivada. En el primer retrocruce se encuentran ya individuos con alto contenido en ácido clorogénico y pardeamiento moderado, lo cual sugiere que es posible introgresar exitosamente el alto contenido en ácido clorogénico de S. incanum en el fondo genético de la berenjena cultivada. En definitiva, los trabajos realizados en esta Tesis Doctoral aportan nuevo conocimiento sobre la diversidad y relaciones entre caracteres implicados en la calidad funcional de la berenjena y otros caracteres de interés en la mejora genética de este cultivo. Los materiales seleccionados y obtenidos son de gran interés para el desarrollo de variedades comerciales de berenjena con propiedades bioactivas mejoradas. / Plazas Ávila, MDLO. (2015). Caracterización y mejora genética de la berenjena (Solanum melongena) para compuestos bioactivos [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48563 / TESIS
215

Aplikace teorie formálních jazyků v oblasti počítačové bezpečnosti / Formal Language Theory Applied to Computer Security

Regéciová, Dominika January 2018 (has links)
Computer security is and will always be a critical area that affects everyone. Despite all the efforts made to build safer systems and test them, however, new vulnerabilities and vulnerabilities are still emerging and creating the impression of tilting at windmills. Partial justification of the current state, but also possible solutions, brings in many respects an extraordinary view of security through formal language theory. Emphasis should be put on a more responsible approach to the recognition and processing of inputs, which are often the gateway to many attacks. In this paper, we will get acquainted with this trend and its recommendations for development and will then introduce a new method of detecting SQL injection attacks built on its foundations.
216

Aplikační rozhraní pro podporu grafiky v jazyce VHDL / Application interface for handling graphics in VHDL language

Vlček, Petr January 2009 (has links)
The objective of this thesis is creating interface for the picture generator. The interface generates a VGA signal with possibility of 4bit color depth. The interface controls two chips of one port SRAM IS61 witch is supplied with Digilent Spartan-3 Starter Kit Board and comunicates trought FIFO blocks based on the shift register principle. Graphics interface generates lines and secondary forms, circles and secondary forms, fills area up and controles 2D transformations of picture.
217

Hodnocení kvality osvětlení s využitím moderních softwarových prostředků / Evaluation of Lighting Quality Using Modern Software Tools

Fazekas, Tibor January 2011 (has links)
This thesis deals with the evaluation of the quality of lighting with the usage of the latest software products used nowadays. The first part of the work is about indoor lighting, the basic requirements invested in lighting, and the basic concepts of indoor lighting. The second part includes complete search for today's computer implements for projecting, simulating, calculation and analysis of light, their functions and characteristics, including luminance analyzers based on CCD sensors and their software equipment. The last part of the work has the task to model a computer room using softwares which can be found within the territory of VUT Brno, and the task was to assess its lighting. Following this, with the help of luminance analyzer, the task is to capture the scene under different lighting conditions and to evaluate the measured data.
218

Návrh paketového analyzátoru pro bezdrátové senzorové sítě založené na standardu IEEE 802.15.4 / Packet analyser for a Wireless Sensor Networks based on the standard IEEE 802.15.4

Bednařík, Martin January 2011 (has links)
The objective of this thesis is to get familiar with wireless sensor networks technologies and with standard IEEE 802.15.4. and communication principle in wireless sensor networks built on this standard. Main goal of this project is to design a packet analyzer, which is capable to catch data on chosen channel and this data is able to analyze. Part of this project is production of necessary microcontroller software equipment. Another output of this project is do a research of available packet analyzers on market and compare them with analyzer build by this thesis.
219

DWDM v přístupových sítích / DWDM in access networks

Šifta, Radim January 2011 (has links)
The aim of this master´s thesis is an explanation of the problem of optical access networks with wavelength division multiplex, main purpose is to demonstrate the difference between simulation and real measurement. The thesis is divided into several basic thematic areas. At the beginning of thesis is outlined the basic division of multiplexing system, there are discussed the basic solutions of wavelength multiplexes and their possible combinations. The next chapter deals with the active elements, which are an essential part of xWDM systems such as optical lasers, detectors and amplifiers. The following chapter is focused on the passive elements, especially on the passive filters, which form a key part of the wavelength multiplex. Methods of measurement C/DWDM networks are discussed in the next part of thesis. The next chapter describes the topology used by active and passive optical networks. Penultimate part of this thesis consists of designs simulated models PON and WDM-PON networks and comparing their transmission parameters. The final part presents the results of practical measurements of experimental optical access network with wavelength division multiplex, the results are simultaneously compared with results of simulations.
220

Komunikační rozhraní pro ovládání spektrálního analyzátoru / Communication Environment for Spectral Analyzer Control

Smělík, Martin January 2011 (has links)
The aim of this master‘s thesis was design a new communication interface for spectral analyzer Seaward EMC Spectrum Receiver, which instead of the RS 232 interface is connected to a computer via the USB interface. This thesis contains both hardware and software solution based on the analysis and comprehensive understanding of communication between the spectrum analyzer and the computer. Further it contains the whole realization of communication interface and an example of measurement of the EMC problems too. Last part of this thesis was a realization of the automatic measurement via the development environment MATLAB and Agilent VEE, which was used for measurement of noise background.

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