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Structures in optical fiber
Polreich, Štěpán ; Čučka, Milan (referee) ; Urban, František (advisor)
This thesis describes the basic concepts, principles and basic characteristics od optical fibers. There are some particular types of structures of optical fibers and their use in practice. The work is also presented technology of these structures. For each of the structures is also described in which field are used, if is area of sensor technology or telecommunication technology. Considerable part is dedicated to special structures that are used especially in sensor technology thanks to its high sensitivity. The thesis describes the design of structures which have been machined by using a femtosecond laser and then states in which area thus treated fibers are used.
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Optical Distributed Sensor Systems
Dorazin, David ; Münster, Petr (referee) ; Čučka, Milan (advisor)
This bachelors thesis solves possibilities of utilization optical fiber as a sensor. At the beginning the thesis desribes basic principle of ligh transmition in optical fiber, optical fiber and his linear and nonlinear properties. Second part of the thesis deals with sorting of distributed optical fiber sensors and describes each type of the sorted sensor due to principle which they work on. The Michelson interferometer is described and its modification in the form of the Fiber optic Michelson interferometer, which is designed and simulated in the VPIphotonics software. At the end of the thesis is performed measuring of vibrations by the Fiber optic Mach-Zehnder interferometer.
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Fiber optic sensors
Janďourek, Leoš ; Šifta, Radim (referee) ; Čučka, Milan (advisor)
Term paper deals with optics, optical fibers and in particular with optical sensors, which are described in more detail. Furthermore, we introduce a new simulation program from VPI photonics. We will show the user interface and the possibiliti of sumulation in it.
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Usage of polarization multiplexing in optical access networks
Jakoubek, Petr ; Čučka, Milan (referee) ; Šifta, Radim (advisor)
This thesis reviews polarization multiplexing and its similarities, advantages and disadvantages to other types of multiplexing methods. The basics of optical fibers and its effects on transmission are discussed in terms of commonly used multiplexes. Additionally, divisions of optical access networks and multiplexing methods which could be used simultaneously with polarization multiplexing along with active and passive elements used for high-speed transmission such as polarization multiplex are described. Practical measurements of temperature influence to polarization and signal crosstalk in the amount of 70 °C and -40 °C are also included. The practical and theoretical measurements on 1 Gb signal led in G.652.D fiber for different situations are examined. Measurements containing 1 Gb signal includes test on triple play services (voice, video, data). First practical measurement on 1 Gb transmission shows how white noise, representing analog television, transmitted in the first polarization beam affects the signal in the second polarization beam. Second practical measurements show how two data streams transmitted through a single fiber at the same wavelength, but different polarization beams, creates a full duplex connection between two network elements. Results confirm the possibility on the usage of polarization multiplexing in optical access networks at common temperatures.
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Modern video codecs
Bílek, Jan ; Čučka, Milan (referee) ; Číka, Petr (advisor)
This bachelor's thesis focuses on modern video codecs and its output video quality assessment. Firstly, principles of some objective and subjective assessment methods are explained. Afterwards, the most common video codecs are introduced, namely H.264, H.265, VP8, VP9, Dirac~2.2.3, WMV and Sorenson Spark. The outcome of this thesis is a desktop application named VideoCodecs written in C++ language, which uses ffmpeg library for encoding and decoding tasks. As a part of the application, algorithms PSNR, SSIM and M--SVD for objective video quality assessment were implemented. Furthermore, a simulation of transport channel was included, enabling us to bring errors into provided video. Using this application, video quality measurements were carried out, on four test sequences in HD resolution at several bitrates. According to our results, the best video codec regarding the video quality is H.265 before H.264, VP9 and VP8.
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Web portal for the video transmission from IP cameras
Čučka, Milan ; Doležel, Radek (referee) ; Zeman, Václav (advisor)
This work is about methods for transferring an image from the web cameras, IP cameras and the creation of a live transmission of television cameras with streaming server and subsequent placement on the web. The first part deals with basic methods of webcam image transfer. This information is described in detail, in next section. The third section describes using of IP cameras for live broadcasts or transmission to a common frame. The last section describes creation of a streaming server and the process of creating a live transmission. There are the advantages and disadvantages of each technology. At the end of the work is given the most frequently used multimedia data formats.
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Optical fiber point sensors
Okoun, Petr ; Čučka, Milan (referee) ; Urban, František (advisor)
This diploma thesis analyzes a structure of spot optical sensors with longitudinal grid and multiple Bragg grating and possibilities of spot optical sensors use and implementation in the industry. Basic principles of light propagation through optical environment are described in the introduction part, followed by description of phenomena in optical fibers and sensors. The distribution of fiber optic sensors and the use of optic fiber in spot mode is described further. The optical sensor system is designed on the basis of analysis with description of its construction at the end of this work. A significant part is devoted to the analysis of longitudinal structures in the fiber in response to multiple Bragg gratings, their subsequent manufacture and suggestion of use in sensors industry.
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Possibilities Lending to Company by Choosen Bank and Non-bank Entities
Šprta, František ; Čučka, Milan (referee) ; Rejnuš, Oldřich (advisor)
The Bachelor thesis is focused on the comparison of commercial banks and non-banking credit companies in term of the supply of business loans to businessman. The comparison is performed based on an analysis of the supply of business loans provided by subjects selected out of the Czech financial market. Selected loans will be compared by selected criteria. The result is a selection of the most favorable loan for specific company.
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Search storage of fiber optic cables
Čučka, Milan ; Dostál, Otto (referee) ; Filka, Miloslav (advisor)
This work deals with the possibilities of laying and reverse lookup optical routes with the help of modern technology. Hereinafter, there are possibilities for documentation and registration of fiber optic lines. Speaking of thesis, it focuses on optical technology, advantages and disadvantages of this technology. Introduction focuses on fiber optic cable and related theoretical knowledge. Additionally, there are introduced comparisons with metallic lines. Another part is based on different searching methods for optical cables using metallic elements are analyzed in a detail. This section discusses galvanic and inductive methods. Subsequently, the thesis deals with searching for optical paths with the help of EMS (electronic marker system). Moreover, there are described individual types of electronic tags which are used in the installation of different kinds of lines. There are also briefly described seeker EMS markers, made by Dynatel. In addition to my work you can find the description of GPS (Global Positioning System) technology and routing the cable with the help of GPS system. Finally, possibility of documentation and evidence in the ArcGIS from ERSI and in the SPIDER-fiber from Gisoft is given. The overall functions of individual programs and their options are analyzed. The last section presents the implementation of laboratory tasks and programming burial markers, creating navigation in Urwigo and realisation with Openwing in Nokia phone. In the end of the work is map with markers positions.
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Optical information transmission - transmission security
Kondicz, Dávid ; Čučka, Milan (referee) ; Filka, Miloslav (advisor)
The submitted work deals with issues of optical transmissions and its security. We will become familiar with a variety of transferability of information, based on which we can assess the advantages and disadvantages of each technology as compared to optical information transmission. Based on acquired information we will try to implement interception of optical communication of cable TV provider.
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