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Optical fibre factors that limit thetransmission capaity of optical lines
Rouča, Tomáš ; Tejkal, Vladimír (referee) ; Reichert, Pavel (advisor)
Bachelor´s thesis more closely specifies effects of attenuation and dispersion of optical fibers in connection with influencing transmitted signal bandwidth and data transfer capacity. It also examines the influences acting on the optical signal passes through an optical fiber and the mechanism that lead to the attenuation or complete suppression of the signal. The first chapter describes in detail the transmission environment in terms of optical fiber attenuation characteristics of the signal loss caused by rough handling of the optical fiber, manufacturing and material specifications, resulting in scattering or absorption of the transmitted signal. Also, whether the description of fiber dispersion, resulting in the shrinking spectrum of transmitted signal and thus the amount of data at a certain point in time transfer to a defined distance. The second chapter analyzes the effects of attenuation and dispersion in fiber optic transmission capacity currently used in presently optic cables, mechanical couplings, connectors and active components. By mentioning a few examples of real transmission lines with regard to the spectral transmission characteristics that these systems require. This study also includes protocols used to transfer information using xWDM systems. The third chapter deals with modern methods to establish a number of optical signals into a single transmission fiber. Particular attention is devoted to describing the principle of association of the channels in the optical frequencies xWDM, since this method does not currently have a standard solution of information transmission optical fiber for its use significantly more bandwidth, longer distances while maintaining vaulted speed transmission and the possibility of flexible extension without laying new cables and reduce the cost of building transmission lines. The last chapter focuses on describing the implementation of a mathematical model to the spectral characteristics of optical fibers.
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Measurement of the fiber optical transport links
Ambrož, Jan ; Škorpil, Vladislav (referee) ; Reichert, Pavel (advisor)
This thesis deals with the measurement of optical transport links. In particular, the measurement of attenuation, chromatic and polarization mode dispersion. Specic me- asurement systems using a WDM and passive optical networks. Within each chapter are listed the causes and eects restrictive factors and methods of measurement. In chapter Attenuation measurements are described radiation and material loss as the main causes of depression. Methods whitch are described two lengths, insert loss and reectometri. Chromatic dispersion at dierent speeds of various wavelengths limits systems with high transfer rate. Methods of measuring the phase shift, dierential phase shift, pulse time delay and interference. Polarization mode dispersion is a random phenomenon caused double refraction, must be measured after completion of the route. Scanning wavelen- gth, traditional and general interference, reectometri and the polarimetric are methods of measurement. It described the measurement of WDM systems in three stages of its build. In brief PON networks are presented, with the specicities of the measurement over splitter. Most chapters are supplemented by the results and conclusions of practical measurements. At the end of the work are given by the two standards deal with the measurement of optical transport links.
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Noise Source Identification Using Nearfield Acoustical Holography
Nevole, Tomáš ; Míča, Ivan (referee) ; Schimmel, Jiří (advisor)
This master’s thesis deals with problems of noise source identification using nearfield acoustical holography (NAH). In the beginning there is the summary of basic terms and values of a sound pressure field, which is unnecessary for understanding of the theme. In the next part the thesis continues with more detailed description of the NAH technology and the historical context of its emergence. Measurement equipment which is used for scanning of sound pressure fields is also introduced. In addition, the kinds of NAH (according the shape of the wave front) are showed and the planar NAH is descripted most closely. Because of the NAH algorithms are implemented in the wave number domain (k-space), there is also a chapter focused to this problem in the thesis. There are briefly descripted some similar methods in next chapter, like statistically optimized NAH, (SONAH) and iterative NAH with recursive filtration. The main product of the thesis is the practical part represented by testing application. That is created in the Matlab environment and is able to calculate and display hologram of the scanned array by the planar NAH method using the “k-space” filter. The application supposes a planar sound source and in other cases the accuracy of the reconstruction is not guaranteed. There are also given some holograms calculated with the application.
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Use of RFID in logistics
Skála, Michal ; Pour, Jan (advisor) ; Basl, Josef (referee)
The Bachelor thesis focuses on two best-known technology automatic identification, barcodes and radio freguency identification (RFID). The goal is to acquaint readers with these technologies and describe a possible procedure implementating RFID to logistics warehouse. At the beginning of the work are presented theoretical information, that are important to understand these technologies. Using practical experience I am trying to outline the introduction of RFID to logistics warehouse. The main contribution of this work is to look at the issue of the implementation of automatic identification from another perspective, to introduce RFID technology, which expects a promising future and shows detailed analysis of the cost of RFID tag. The second chapter describes the most known bar-code technology, since its creation to the present. There are listed the most common types of bar codes and equipment used to scan bar codes. The third chapter focuses on RFID technology. It deals with different types of RFID systems in terms of functionality and differences between them. There are presented the equipment needed to run the system. The fourth chapter deals with the safety of RFID technology in terms of threats and understanding the reasons for the attack on the technology. The fifth chapter focuses on the analysis of prices of a particular RFID tag. It examines why prices are that high and how the price could change in the future. The sixth chapter describes a possible procedure for implementing RFID into the logistics of a particular stock. It includes a SWOT analysis, which highlights the strengths and weaknesses of this technology. The seventh chapter predicts the possible development and application of RFID in the future.
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TV Serial as a Social Medium
Havlová, Jana ; Krtilová, Kateřina (advisor) ; Řehořová, Irena (referee)
Divided into a theoretical and practical part, this master's thesis is concerned with TV serials as a social medium. The theoretical part introduces some of the theories of postmodern times (Baudrillard, Virilio, Lipovetsky, Bauer and Bauman), further it analyses the concepts related to media communication and their interrelations (Thompson, Jirák, Köpplová, Berger, Luckmann, Burton, Barhes) in oder to provide a theoretical framework for the analysis of the particular TV serial "Sex and the City" in the practical part of the thesis. With respect to the serial character and content it includes also a gender perspective.
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Karel Pivoňka and bassoon´s class of HAMU from beginning to present
Propilková, Denisa ; SEIDL, Jiří (advisor) ; HERMAN, František (referee)
The title of my master's thesis is Karel Pivoňka and Academy of Performing Arts in Prague and bassoon class from the beginning to the present. In the first chapter is the development of czech bassoon school and everything that preceded the bassoon class of Academy of Performing Arts. In the first chapter is subchapter where I mention the personality of Karel Bidlo, which also had an effect on the development of czech bassoon school. In the second chapter I discuss Academy of Performing Arts, the school and individual departments. In the third chapter describes the personality of Karel Pivoňka and in the subchapter are listed all the graduates of the Conservatory and the Academy of Performing Arts, which studied at prof. Karel Pivoňka. In the following chapter are the most significant graduates from the beginning to the present. The last chapter is an overview of most concerts and broadcasts for radio, which played Karel Pivoňka. Annex is scanned photo of Karel Pivoňka.
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The use of optical methods in the diagnosis of electrical machines
Tobolák, Petr ; Kuchyňková, Hana (referee) ; Janda, Marcel (advisor)
This term describes questions of scanning rotors of asynchronous motors using 3D scanner. At the beginning it deals with a theory of asynchronous motors, defects of these machines and last but not least also questions of 3D scanning. Directly it focuses on a practical processing of measured rotors and their necessary modifications using of a program GEOMAGIC. It includes a diagnostic of deviations of scanning components of rotors with a model created on a program AUTODESK INVENTOR and posiible reasons of their creation.
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Reaction time of sports horses.
KERNEROVÁ, Nina
In this thesis were charted information and methodology about reaction time of horses on optical stimulus. As an optical stimulus was used vehement and unforseen movement by white board (500 x 500 mm) on which horses reacted very well. Reaction scanning was made by high-speed video camera MotionScope 9400, which was connected to a computer. In total was evaluated group of 35 horses. The average age was 5.8 years, the average reaction time on optical stimulus was 152 ms. In experiment was group of 14 thoroughbreds and 21 warmbloods. Group contained 4 stallions, 17 geldings and 14 mares. The largest group was represented by 5 years old (10 representatives). By the thoroughbreds was found out reaction time 154 ms, by the warmblood group 150 ms. Differences between breeds were not statistically significant. The lowest average reaction time was measured out by stallions (139 ms), then mares (149 ms) and the highest rate was by geldings (157 ms). The difference between reaction time of geldings and mares was not statistically significant. The lowest rate was measured out by the age group from 2 to 4 years old (142 ms), then group of 6 to 13 years old (156 ms). The highest rate had group of 5 years old (159 ms). The differences between age groups were not upholded as statistically significant. The correlation coefficient expressing relation between age of horses and reaction time on the optical stimulus was found out very low, that means that it is not statistically significant. In this thesis was proved, that as well as humans, horses react more quickly on acoustic stimulus than on optical stimulus.
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