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HIL simulation of manipulators or machines
Dočekal, Martin ; Marada, Tomáš (referee) ; Zuth, Daniel (advisor)
The diploma thesis deals with HIL simulation (hardware in the loop). The thesis contains a manipulator created in the virtual software V-REP. The connection of real inputs and virtual outputs of the machine is realized by the microcontroller Arduino UNO. The first task deals with the control of the manipulator using the joystick PS2. The second task is a separate control of the robot using an microcontroller Arduino UNO. The resulting connection can be modified in the furher and the interface modified. The work will be used for educational purposes.
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Teaching Advanced Python through Automatic Feedback to Student Codes
John, Petr ; Dočekal, Martin (referee) ; Smrž, Pavel (advisor)
This bachelor thesis focuses on the topic of teaching Python programming language assisted by automated system that can provide feedback to submitted solutions. The goal of this thesis was creation of automated system that could evaluate student solutions and provide feedback. The main emphasis was on provided feedback and options for limiting resources that can be used. Created system provides feedback based on the analysis of abstract syntax trees assembled from submitted solutions, allows an administrator to attach tips from third party programs and set restrictions on resources, libraries and functions, that can be used. System was used during summer semester in ISJ course and 60 % of students improved their solution based on feedback given by system. This suggests that created system can be used during Python tuition.
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Creating Dataset for Narrative Structure Recognition by Crowdsourcing
Ignác, Igor ; Dočekal, Martin (referee) ; Smrž, Pavel (advisor)
Goal of this work is creation of extensive dataset for recognition of narrative structure by crowdsourcing method. For this purpose, it was necessary to create a web interface which offers dataset of films for user annotation. The annotation of data gained from IMDb database is established on three different types of annotation. Users validate similarity of movies based on computation done by Sentence-BERT, extraction of keywords from movie plots done by RAKE and precomputed similarity between movies based on their keywords. User's gamification is based on points assignment, which are related with badges, achievements accomplishment and leader board of most successful users.
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Comparison of Classification Methods
Dočekal, Martin ; Zendulka, Jaroslav (referee) ; Burgetová, Ivana (advisor)
This thesis deals with a comparison of classification methods. At first, these classification methods based on machine learning are described, then a classifier comparison system is designed and implemented. This thesis also describes some classification tasks and datasets on which the designed system will be tested. The evaluation of classification tasks is done according to standard metrics. In this thesis is presented design and implementation of a classifier that is based on the principle of evolutionary algorithms.
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Experimatal Analysis of Windshield Wipers Motors
Dočekal, Martin ; Mach, Martin (referee) ; Hájek, Vítězslav (advisor)
The work deals with the methods of measurement of small DC motors, especially motors used for drives wiper’s mechanisms. Furthermore, describing the internal structure and function of wiper’s engines. Measurement of these engines is carried out mainly dynamometers which is described in more details in the work. However, measuring systems consist not only from the dynamometer but also many other components such as controllers, software for testing engines, various stands, temperature and speed testers, and many others. These components are taken into account, when selecting the most suitable measuring system. There are also various systems analyzed and compared in terms of both technical and economic parameters, but also in terms of measurement options, such as immediate viewing characteristics on a PC monitor of the system assembly, the possibility of measuring the friction torque, efficiency, heating, etc. In conclusion, there is a recommendation of measuring system which I chose as the best option according to its parameters.
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Tribological behavior of detonation nanodiamond dispersed in lubricants
Dočekal, Martin ; Čermák, Jan (referee) ; Svoboda, Petr (advisor)
Currently tribological laboratories are looking for a new type of solid ingredients, to create a lubricating composition with minimal friction, heat resistant, with particles well dispersed in oils, sedimentation stable, improving the running properties and to minimize the concentration of solids. Nanodiamonds (DND) could exhibit the possible solution. These particles (in nanometers size) have very good physical and chemical properties, high hardness and resistance. The main advantages are effectiveness at low concentrations, compatibility with various types of oils or environmental safety (carbon additive, unlike metal) in a comparison with other types of additives. However, it is necessary to study these ingredients. The aim of research was to examine the influence of diamond nanoparticles on friction in a lubricated contact (elastohydrodynamic mode). Using tribological equipment, 3D optical profilometer and a microscope, we compared and evaluated using oil with diamond nanoparticles as well as without them. The research focused on the behavior of nanoparticles in contact and the effect they have on friction. To assess these properties of nanodiamonds, EHD optical tribometer was used (this is a device designed for the study of thin lubricating films). 3D optical profilometer and a microscope to assess the wear. And to determine the relationship between the coefficient of friction (COF) and time, Mini Traction Machine was used.
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Design of the electric locomotive drive
Dočekal, Martin ; Klíma, Bohumil (referee) ; Patočka, Miroslav (advisor)
The focus of the work is the calculation and design of battery-powered drive of locomotive, operating in the sub-siding mode, ie when the locomotive is moving on the track section without the overhead line. The proposed battery groups to ensure the drive train will be installed directly into the locomotive engine room. In the theoretical part of the work there has been done the analysis of the electrical locomotives and electrical unit, which nowadays are used in the Czech Republic in driving of voltage controller with the integrated circuit. Then, in the chapter there is a brief description modern locomotives frequency convertor’s and rectifier’s function. The practical part of the work contains the necessary force and energy calculation for train moving on the determined rails. On the base of the received data, the design of battery groups has been done. These battery groups will work as an independent traction which insures the moving of the train on the determined rails. In the work the design, which consists of STEP-UP and STEP-DOWN convertors, has also been done. The power model and model management were created in Matlab Simulink programme. Data and graphs exported from the Matlab Simulink programm are determined for verifying convertor’s function, which can be found in a separate chapter. In addition to the proposal of the battery drive is at work also has been calculated loss of traction rectifier during normal operation of the locomotive, ie outside siding mode. For this calculation, in the conclusion is listed the theory of calculation of the losses incipient in the transistor and freewheeling diode of rectifier. According to the theory own calculation is performed. Subsequently the liquid cooler calculation of the rectifier is calculated.
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