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Measuring device connected over USB
Flek, Tomáš ; Strašil, Ivo (referee) ; Krajsa, Ondřej (advisor)
In essence, this master’s thesis focuses on search and project on optimal electrical scheme, which will substitute for digital oscilloscope function. The thesis consist of three parts, first part is about problems associated with oscilloscope signal sampling and data bus descriptions, second part where are selected particular circuits, electrical scheme, eventually shown different options which could be used. Third part consists of software function description developed for controlling microprocessor. In choosing of analog devices, are focused on parameters like maximal input voltage on which the device has most ideal parameters, but also parameters, which are critical for particular block, like for example input impedance, device noise, operating amplifier input voltage and current offset. All devices were chosen with battery supply possibility, so what the lowest possible power consumption. In this thesis is theoretically described each circuit block and reasons for their selection.
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Head Pose Estimation and Tracking
Pospíšil, Aleš ; Krajsa, Ondřej (referee) ; Přinosil, Jiří (advisor)
Diplomová práce je zaměřena na problematiku detekce a sledování polohy hlavy v obraze jako jednu s možností jak zlepšit možnosti interakce mezi počítačem a člověkem. Hlavním přínosem diplomové práce je využití inovativních hardwarových a softwarových technologií jakými jsou Microsoft Kinect, Point Cloud Library a CImg Library. Na úvod je představeno shrnutí předchozích prací na podobné téma. Následuje charakteristika a popis databáze, která byla vytvořena pro účely diplomové práce. Vyvinutý systém pro detekci a sledování polohy hlavy je založený na akvizici 3D obrazových dat a registračním algoritmu Iterative Closest Point. V závěru diplomové práce je nabídnuto hodnocení vzniklého systému a jsou navrženy možnosti jeho budoucího zlepšení.
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Vehicle detection in images
Pálka, Zbyněk ; Přinosil, Jiří (referee) ; Krajsa, Ondřej (advisor)
This thesis dissert on traffic monitoring. There are couple of different methods of background extraction and four methods vehicle detection described here. Furthermore there is one method that describes vehicle counting. All of these methods was realized in Matlab where was created graphical user interface. One whole chapter is dedicated to process of practical realization. All methods are compared by set of testing videos. These videos are resulting in statistics which diagnoses about efficiency of single one method.
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Automatic Attendant application using Asterisk PBX
Benýšek, Jiří ; Krajsa, Ondřej (referee) ; Kovář, Petr (advisor)
Application of IP telephony is still more and more popular. This technology is designed for large companies as well as for home or office use. If customer needs to use advanced features of the private branch exchanges, he had to purchase more expensive solutions than common equipment. These professional products may be replaced by open source solutions, which can fully replace them. Private branch exchange Asterisk is one example of these products. Bachelor’s thesis is focused on IP telephony, treats of basic principles and network protocols used by this service. This thesis then describes the public branch exchange Asterisk, its possibilities for use in call centers and administration of call queues using this PBX. After theoretical analysis, this thesis deals with installation and configuration of this PBX. It includes installation of necessary operating system, additional packages containing necessary libraries and modules needed for correct function of the PBX. Configuration of Asterisk such as creation of user accounts of SIP protocol and dialplan is described in the next chapter and then all of these functions are tested. Achieved practical results are presented in the last chapter of this bachelor’s thesis.
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Virtual serial port and its safety conversion to Ethernet
Pokorný, Michal ; Krajsa, Ondřej (referee) ; Koutný, Martin (advisor)
Bachelor´s thesis try to find a solution to make virtual serial port and its safe transfer on Ethernet. Nowdays communications channels don't offer appropriate security of a whole communication. Therefore it depends on get-togethers, in order to realize this security themselves.This means ensure reliable data transfer, these data from among get-togethers encrypt in order to appropriate attacher be unable to read them in real - time, eventually to change them. As a result this Bachelor thesis is the application, which, except transfer between virtual serial port and Ethernet, insure authentication among get - togehthers communication and cipher transfer among them. As an encryption algorithm is used algorithm AES. It is concerned symmetrical cipher, which ciphers data after pages about size 128 byte.
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Thermostat for biological experiments
Štens, Radovan ; Krajsa, Ondřej (referee) ; Chmelař, Milan (advisor)
Master's thesis deals with a design of the thermostat for biological experiments considering 2l of volume, with capability of setting up required temperature between 20-40 degree Celsius and related accuracy of measurement +/- 1 degree Celsius. Following chapters are one by one described and properly explained from possible ways of measuring temperature to final implementation. Result of the thesis presents necessarily calculations, discussion of module's performance modeling, schematics together with PCB's design and the list of components. Neither the question of software nor possibilities of realization is neglected.
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Billing system and call monitoring for PBX Asterisk
Depiak, Petr ; Šilhavý, Pavel (referee) ; Krajsa, Ondřej (advisor)
This master's thesis is focused on developement of billing system with the options of monitoring individual calls for software exchange Asterisk. Billing of calls is adaptible with the help of group of individual rules, consisting of tariff impulses, numerical prefix, with help of outgoing trunk and cost of the billed unit. The first part of this work is focused on instalation, configuration and preparation of individual components of the billing system. In this work is explained the architecture of the billing system and highlighted the purpose of work of the model database. Next we focused on the purpose and the principal system invidual function of the system including solution. At last there is a simple manual to operate the system with the help of created web interface.
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Optimization of data communication over high-voltage lines
Minárik, Peter ; Krajsa, Ondřej (referee) ; Mlýnek, Petr (advisor)
The thesis deals with analysis of the PLC (Power Line Communication) system for data communications through powerlines. In the introduction describes the technology of data transmission through the energy network and is divided into categories corresponding with the explanation of the various specifications and features. Different types of coding, affecting the transmitted signal interference and modulation techniques used in a PLC are also described. The practical part is made up of telecommunications network model with transmission channel realized as additive white noise. The model can setup different types of modulation and coding in relate with the signal to noise ratio and bit error rates. The individual blocks settings are described in detail. The model was simulated. The results of simulation are displayed and evaluated at the end of work.
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Implementing of GSM modem in PBX Asterisk
Benýšek, Jiří ; Krajsa, Ondřej (referee) ; Šilhavý, Pavel (advisor)
Short Message Service (shortly SMS) is the most widely used type of communication systems. The main advantages are that allow a fast exchange of messages between devices, a very good availability through GSM and a reasonable price. Nowadays the SMS service support has expanded to include other technologies such as a service of the information navigation and the remote connection. The master‘s thesis concentrates on the Short Message Service, deals with basic principles and statements using by this service. The topic of the thesis is software PBX Asterisk and its possibility of SMS implementation, especially verification of SMS processing goes through the PSTN. After the basic introduction the master‘s work deals with the installation and configuration of the server. The main focus is on an installation of the operating system with an additional pack including necessary libraries and modules for a correct working of the server. The following section is paying attention to the Asterisk server configuration, especially a hardware card installation which is necessary for a connection with analog telephones, done by Bluetooth connections, set up user’s profiles of the SIP protocol and create a dial plan. This is followed by a verification of SMS option of the implementation and communication with GSM modem which is used as a gate for an exchange SMS between PSTN and GSM network. The last chapter of this master‘s thesis comes with the aimed results.
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Implementation of the channel equalization algorithms used in FMT modulation
Krejča, Libor ; Krajsa, Ondřej (referee) ; Šilhavý, Pavel (advisor)
The objective of Diploma thesis is design of analysis tool for equalizers used in FMT modulation. The model of transmission channel was designed for simulations with FMT. The transmission path is modeled by test loop, which corresponds to DSL line. For this reason, some principles of DSL technology is described in the thesis. The principles of multicarrier modulation are introduced in first part. The multicarrier modulation with filter bank (FMT) is described in detail.The different methods of design the fiter bank are given and compared. Channel equalization are introduced in second part. The attention was focused on minimum mean square error filtering (MMSE). Decision feedback channel equalizer (DFE) is extended from linear MMSE equalizer. DFE equalizers were programmed in analysis tool. For computation of equalizer coeficients was used also equalizers based on adaptive algorithms and MMSE. The last part describes the results of DFE equalizers used in communication system with FMT modulation. Analysis tool was programmed in MATLAB with a graphical user interface. It allows to show mean square error, signal-to-noise ratio and transmission speed dependence on delay between original and distorted signal. Signal-to-noise ration is displayed also in individual subchannels and users can display mean square error dependence on different orders of DFE filters.
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