National Repository of Grey Literature 108 records found  1 - 10nextend  jump to record: Search took 0.09 seconds. 
MV Cables Failures and Malfunctions
Holuša, Martin ; Pelikán, Luděk (referee) ; Krbal, Michal (advisor)
The aim of this diploma thesis is to define cable and his accessories and describe defects and fault which can appear on the cable and his accessories. The thesis also divides the cable and his accessories into individual parts, which are describe in more detail. Diagnostic methods that can be used to detect individual faults and monitor their status on individual parts of the cable and cable accessories are also listed. The thesis's practical part focuses on the test of one component of the cable assembly using PD measurement and monitoring its surface temperature.
Creation of Knowledge Database for Lighting Technology with the Possibility of Expert Query Processing
Krbal, Michal ; Sokanský, Karel (referee) ; Gašparovský, Dionýz (referee) ; Baxant, Petr (advisor)
This presented thesis is focused on the complex description of creation the database system for the lighting. The important static and dynamic parameters of light sources and luminaires are listed in the first part of thesis. These parameters are complemented by the measured values and their relationships. The next chapters of thesis are focused to description of obtained parameters, structural design, historical and expected development of individual representatives of light sources. In the following sections are described current state of used data formats of luminaires and the possibilities for describing of light sources. The database systems are created as a result of this thesis. These databases are used for collecting, sorting, searching and sophisticate comparison of the parameters of light sources and luminaires.
Development of laboratory samples for wireless transmission of electric power based on the magnetic induction
Kopečný, David ; Štěpánek, Jaroslav (referee) ; Krbal, Michal (advisor)
The aim of the thesis is to collect the information about wireless transmission by using magnetic induction and about the current solutions of wireless applications in practice. The thesis includes theoretical basis and information about the current state of wireless power applications. This thesis is also focused on physical principle and draft of possible technical solution. On top of that, it also contains the information from some legislative and hygienic regulations. The second aim is draft of laboratory equipment on the base of gained information and its implementation for purpose of teaching and measuring. For this part was chosen topology of circuit and the specifications of resonance circuits. It resulted in producing a preparation, which consists of the exciter, primary circuit, secondary circuit and a module for measuring. The third aim is to take a measurement on this product and evaluation of characteristic from point of view of efficiency. Measured data were integrated into characteristics. The efficiency of transfer was measured depending on distance and used load. At the same time was also observed work frequency of product. Furthemore, another laboratory product was measured, in which was reached the efficiency more than 51%. The thesis is divided into four main chapters, which can be thematically named as follows: the information, the theory, the draft and the measurement. The first two chapters deal with the theory and characterization of technologies of already applied systems mainly from transport. The following two chapters contain the description of proposal of the product and the very measuring of the efficiency.
Generation of Voltage Wave by Impulse Generator
Poloni, Miroslav ; Krbal, Michal (referee) ; Pelikán, Luděk (advisor)
The presented bachelor thesis deals with the problems and functions of impulse voltage generators. The theoretical part describes the functions and various connections of the impulse generator, types of impulse voltage, tests and test procedures. In the practical part of the work, theoretical knowledge in the form of simulations was verified. The simulations were performed in the LTspice program from Linear Technology, where the impulse generator model was made. Simulations were then performed on the given model of the shock generator, from simpler ones such as the dependence of the size of the load capacity to the inductance connected in parallel. The results of all simulations should bring benefits and ease in real shock generator tests
Street Lighting Control
Kořenek, Jan ; Krbal, Michal (referee) ; Štěpánek, Jaroslav (advisor)
This bachelor thesis deals in a theoretical part with the origin of the light, his features and lighttechnical quantities. There are also characterized light sources, which are currently most used to control street lighting. There are further described basics of the street light and currently most used ways of street lighting control. Further part of this thesis is focused on practical control of different types of light sources and monitoring their parameters, such as luminous flux, power, efficiency or correlated colour temperature during voltage reduction. These light sources are high pressure sodium lamps, halogenid lamp, fluorescent lamp and high pressure mercury lamp. Main conclusion from measurements are several cross characteristics, where is possible to monitor behavior of the parameters during voltage reduction. The last part concerned about practical street lighting control in Bezděkov, which is a village located near Havlíčkův Brod. There was connected the dimmer. On the street was created net of points according to the standard. In these points were measured illuminance for voltage 230 V and then for lower voltages 210 V and 190 V. These values were processed and average and minimum value was compared with the value defined in the standard.
The development of electrodeless fluorescent lamps and their applications in lighting
Šenk, Tomáš ; Škoda, Jan (referee) ; Krbal, Michal (advisor)
The aim of this thesis is more familiar with electrodeless fluorescent lamps. In work is on introduction to the historical development of electrodeless fluorescent lamps, as is explained by their principle of operation and briefly discussed three basic design of these light sources. Subsequently there is mentioned some unique characteristics of electrodeless fluorescent lamps, which are different from other commercially available light sources. After explaining some light - technical variables. The work also provides a comparison of the parameters electrodeless fluorescent lamps with other available light sources. Further there are listed detailed parameters of several types electrodeless fluorescent lamps available in the Czech Republic. A description of possible applications in various types of light fitting. The next section describes the ballast system needed to supply the light sources. Below it is shown and described several start-up characteristics of the luminous flux of different types of electrodeless fluorescent lamps and various levels of compensation current drawn by induction lamps. There are also some parameters of available ballasts systems. Furthermore, given the possibility of applying electrodeless fluorescent lamps in extreme conditions. The conclusion is stated measurements of several cross characteristics of electrodeless fluorescent lamps.
Breakdown Voltage Measurement of Solid and Liquid Dielektric Materials
Ryšavý, Tomáš ; Pelikán, Luděk (referee) ; Krbal, Michal (advisor)
This thesis aims to theoretically describe the formation of electric breakdown in solid and liquid dielectric materials and subsequently focuses on the measuring itself. In addition to describing the standardized procedure of electrical breakdown or breakdown voltage of dielectric materials, this paper also focuses on the most important parameters and conditions that affect the electric strength of materials. This thesis also includes designs of electrode systems and test chambers for measuring solid and liquid dielectrics.
LED technology for Lighting Plants
Pospíšil, Tomáš ; Pavelka, Tomáš (referee) ; Krbal, Michal (advisor)
The aim of the work is to describe the physiology of plants and their needs to the successful evolution and growth. Furthermore to introduce a characteristic light requirement of plants and summarize differences between light requirements of the human eye and plants. More there are shortly mentioned the light quantities and units and by means of these quantities and their units there is assessed the appropriateness of lighting for plants. Another aim is to describe the electric and lighting-technical LED parameters that are suitable for use as a lamp designed for illumination of plants, outline the basic requirements that should the lamp designed for illuminating the plants fulfill. The last part is devoted to the presentation and evaluation of the measurement results of the lamp, which was already developed and used on prototype light source using LED.
Wireless Energy Transfer
Lašo, Matej ; Paar, Martin (referee) ; Krbal, Michal (advisor)
The aim of this Bachelor's thesis is to give complex information about wireless energy transfer and its historical evolution. The thesis then continues with describing the devices that are using wireless energy transfer and the effects this method is having on human health and the ways protecting against its effects. The second part, concerning practical measurements, aims at measuring on special pads using the wireless transfer on which I have made all my calibrations and measuring of magnetic flux and efficiency of this transfer.
Design of the morning sun simulator
Suský, Stanislav ; Krbal, Michal (referee) ; Štěpánek, Jaroslav (advisor)
This work deals with the introduction of the influence of electromagnetic radiation on circadian rhythms and their influence on the organism. The work describes circadian rhythms and their influence on the organism, the location and description of functions of important organs and the influence of electromagnetic radiation on these organs. There are described light sources and their influence on circadian rhythms.

National Repository of Grey Literature : 108 records found   1 - 10nextend  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.