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Psychoacoustic model of human hearing
Lepa, Ondřej ; Smékal, Zdeněk (referee) ; Sysel, Petr (advisor)
This thesis deals with human auditory system and psychoacoustics. Deals with psychoacoustic model of standard MPEG following the norm ISO/IEC 13818-3, Information technology - Generic coding of moving pictures and associated audio information Part 3: Audio. Closer look is given to determination of PAM, to methods of masking and what potential of masking it has. Next the simple computation of psychoacoustic values is~done in Matlab environment.
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USB Host with PIC Microcontrollers
Kučera, Pavel ; Janoušek, Vladimír (referee) ; Hanáček, Petr (advisor)
The aim of master thesis is implementation of USB host in a microcontroller PIC. The thesis contains description of ways of peripherals to computer connections with detailed description of USB bus. There are also discussed several approaches in implementations USB host for embedded systems. A concept of layered USB host system is designed on the basis of analysis of the state of the art. Finally, the designed system is implemented in microcontroller. Resulting firmware of development kit is tested on real USB device.
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Mechanical and Electrical Properties of Thin Metal Films Deposited by Vacuum Evaporation
W. F. Yahya, Doaa ; Kolařík, Vladimír (referee) ; Štencl,, Jiří (referee) ; Šandera, Josef (advisor)
Thin layers are widely used in many fields of technology and today we can say that they are found in all modern technologies. Thin layers can be created in two ways, namely by chemical or physical means. This work focuses on the latter method, more particularly a technology of thermal evaporation of thin layers in a vacuum. The work focuses on the process principles during and after the evaporation. Much of the work focuses on the development and design of experiments. These experiments illustrate some of the phenomena that take place on thin films produced by the aforementioned technology. Work helps to better understand processes during formation of thin layers and properties that influence the quality and stability of thin films. In conclusion we describe results of experiments and new developments in the field of thin films deposition using evaporation under vakuum are summarized.
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Analysis of an Electromagnetic Wave on the Boundary between Electromagnetic Materials
Kadlec, Radim ; Lazar, Josef (referee) ; Macháč, Jan (referee) ; Kroutilová, Eva (advisor)
The proposed dissertation thesis contains an analysis of conditions on the boundary between layers having varied electromagnetic properties. The research is performed using consistent theoretical derivation of analytical formulas, and the underlying problem is considered also in view of multiple boundaries including the effect of the propagation of electromagnetic waves having different instantaneous speed. The author presents a survey and formulation of the basic characteristics of methods used for electromagnetic wave propagation analysis; in this respect, special emphasis is placed on radial models. The processing of the topic involved the designing and verification (using a set of different, layered planar materials) of algorithms to analyze the electromagnetic field components. The algorithm was assembled to enable simple evaluation of all components of the electromagnetic field in relation to the speed of the wave propagation in a heterogeneous environment. The proposed algorithms are compared by means of different numerical methods for the modelling of electromagnetic waves on the boundary between materials; moreover, electromagnetic field components in common points of the model were also subject to comparison. When in conjunction with tools facilitating the analysis of material response to the source of a continuous signal, the algorithms constitute a supplementary instrument for the design of a layered material. Such design enables the realization of, for example, recoilless plane, recoilless transition between different types of environment, and filters for both optical and radio frequencies.
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Study of luminicsence properties of organic semicondustors
Koňák, Petr ; Horák, Michal (referee) ; Boušek, Jaroslav (advisor)
This document describes using organic semiconductors to the electroluminescence on thin layers. In introduction of this file there is analysis a the problem of organic semiconductors and it's using in today's world. Next, I want to describe work with the given samples, their chemical composition and also include results from the measuration of electroluminescence.
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QoS in UMTS
Kavan, Radovan ; Hanus, Stanislav (referee) ; Kejík, Petr (advisor)
This thesis treats of QoS (Quality of Service) in UMTS system. The term quality of service is frequently used, recently, however not only in computer networks, but also more and more in mobile networks also. Present system of 2nd generation (2G) GSM enables only limited exploitation of QoS function. System UMTS is a system of 3rd generation (3G) already and contains quality of service in greater measure which is ensured with number of algorithms and functions. Individual QoS functions enable effective utilization of radio interface, support maintenance of planned coverage and offer high spectral efficiency. Functions that cater to quality of service are called RRM functions (Radio Resource Management). There exist five basic functions in UMTS system that are Admission control (AC), Power control (PC), Load control (LC), Handover control (HC) and Packet scheduler (PS). These functions are responsible for control of network access, control of power, control of network load, control of handover and packet (bit rate) scheduling. Last three functions are usually collectively designated as Congestion control, control of network overload. UMTS layer model, differentiation of services, traffic classes and 3GPP concept are also discussed. In thesis the attention is piad to Admission control algorithm – control of network access – in the uplink direction and to different ways of load (in the cell) modeling. Individual approaches are simulated in MATLAB. A possibility of using algorithm in the real system is discussed in conclusion.
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Reflex Treatment of Transparent Materials
Meluzín, Ondřej ; Tulka, Jaromír (referee) ; Molliková, Eva (advisor)
This thesis deals with the possibilities and methods of coating of transparent materials in order to improve their optical-reflective properties. It describes various methods that nowadays coatings can be applied on an industrial scale, while maintaining a constant thickness and properties across the applied coating. Further provides specific examples of how the application of different optical coatings can improve the desired properties of materials used for technical applications.
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Computer control of the deposition process
Pavera, Michal ; Voborný, Stanislav (referee) ; Urbánek, Michal (advisor)
This bachaloers thesis deals with automation of the deposition process of the ultrathin layers by IBAD method. One of the tasks is to design motorized target and shutter manipulator. The thesis therefore contain drawings of these manipulators. Which enable their control by stepper motors. Second task is to design of electronics and program control of primary and secondary ion source. In this part is described connection of the system with the computer using AD/DA converters and the appropriate programming. Last part of the thesis deals with differences between automated and manual control of the system, their advantages and disadvantages.
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Aplikovatelnost nové metody pro lepší diskretizaci valmi malých hloubek vniku
Musil, Ladislav
The paper deals with tests of a new suggested method for an easier discretisation of thin layers of electromagnetic field penetrating into a conducting material. First the principle of the new method and its derivation is described. Comparison of computation with and without the transformation follows. The comparison is done on several very simple arrangements of induction heating of a ferromagnetic material. The computation were carried out by the FEM based professional code of FEMLAB supplemented with single purpose scripts written by the author in MATLAB and MATHEMATICA.
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