• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 46
  • 4
  • Tagged with
  • 50
  • 47
  • 17
  • 16
  • 12
  • 9
  • 9
  • 9
  • 9
  • 8
  • 8
  • 8
  • 8
  • 8
  • 7
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Virtuální měřicí systém pro nestandardní bezodrazové komory / Virtual Measurement System for the Anechoic Chambers

Váško, Ondřej January 2013 (has links)
Master thesis examines a selected part of electromagnetic compatibility. In this work, there is theoretically discussed how electromagnetic interference appears and how is spread through free space environment. To eliminate ambient interference signals, the measurements have been performed in anechoic chamber where the undesirable interference signals were suppressed. In the thesis, there are also described parameters of EMI receivers and limits of electromagnetic interference. The description of calculations of the antenna height for finding maximum intensity of electric field strength for standard measurement distance has been made. For proposed transformed measurement distance, calculations of intensity electric field with addition of parameters measuring antenna and object under test were performed. Correction curves for conversion intensity electric field have been obtained as the result.
12

Návrh elektromagnetického laboratorního vibrátoru / Design of electromagnetic laboratory shaker

Vaněček, Michal January 2011 (has links)
My thesis describes the design of a laboratory electromagnetic vibrator, which will be used for testing of the vibrating microgenerators. In the first part of my thesis is the search of selected laboratory electromagnetic vibration generators. There is also formulated its own proposal and subsequent tuning of the required dimensions and characteristics of the laboratory electromagnetic vibration generator. The tuning of necessary properties and dimensions is formed as modeling and simulating in programms Matlab / Simulink and ANSYS. The conduct of laboratory electromagnetic vibration generator is implemented in MATLAB / Simulink. Design and dimensions of the laboratory electromagnetic vibration generator is made in SolidWorks.
13

Přístroje EMD a jejich ovlivnění / EMD instruments and electromagnetic mmunity

Mikula, Dalibor January 2009 (has links)
The work deals with implantable devices and possibilities of interference of elektromagnetic field. At first, the electromagnetic compatibility is discussed. Basic terms are explained, followed by insisting on resources of possible distrurbing of implantable devices and standards dealing with this issue. Furthermore, short chapter about devices affecting function of implantable devices is introduced. It means devices which patients with implantable devices may meet in common life, as well as devices used in common life, also devices used jn medical environment. In the next part, measuring process of electromamagnetic effect in working compartment of FN Brno magnetotheraphy and elektrotheraphy is devised. There is a concept of measuring card thanks to which impulses of implantable devices are measured. Finally, a description of measuring on implantable devices in FN Brno. MIKULA, D. EMD instruments and electromagnetic immunity. Brno, 2009. 74 s. Master’s thesis in Brno University of technology on faculty of elektrical engeenerig and communication. Supervisor Ing. Marie Havlíková , Ph.D.
14

Měření elektromagnetického vyzařování v částečně a plně bezodrazových komorách / Measurements of electromagnetic interference in anechoic and semi-anechoic chambers

Deneš, Roman January 2015 (has links)
This thesis is focused on a detailed analysis of the mechanisms of electromagnetic wave propagation in anechoic chambers. The analysis takes into account the influence of the measurement distance, setup of anechoic chamber and other parameters. Furthermore, the work deals with a validation of both types of anechoic chambers and examines the impact of selected parameters on the measurement results. Based on the theoretical analysis and practical measurement, the comparation between semi and fully anechoic chamber, or a three and ten meter measuring distance was made. This thesis also contains a detailed analysis of sources of the uncertainty.
15

Servisního modulu pro automatickou sanitární techniku / Service device for automatic sanitary equipment

Kudláček, Martin January 2018 (has links)
The aim of this thesis is to inform readers about the basic principle of electronics for which the service module for the automatic sanitary technique will be designed, as well as design and describe the most important parts of the module theoretically. Likewise, the thesis deals with the most common mistakes in the design of printed circuits boards with respect to the resistance of the resulting device against interference. The implementation itself includes both module design and a communication algorithm for connecting multiple service modules and their remote control using the Raspberry Pi minicomputer. The thesis also contains a design of algorithm for verification of data transmission by the transmission system.
16

Bezkontaktní zatěžování a měření vysokootáčkových strojů / Contactless loading and measurement of high-speed machines

Vojče, Zbyněk January 2018 (has links)
Práce se zabývá problematikou měření momentu u velmi vysokootáčkových strojů. Z důvodů vysokých rychlostí jsou tradiční metody měření momentu nepoužitelné, z tohoto důvodu je nutno vyvinout novou bezkontaktní metodu. Pro měření je zvolena metoda zatěžování vířivou brzdou, pro kterou je proveden analytický výpočet jejích vlastností pomocí Maxwellových rovnic a je vytvořen model vířivé brzdy v programu FEMM a Ansys/Maxwell 2D. Na závěr jsou výsledky simulací a výpočtů porovnány s měřením na prototypech brzdy.
17

Vliv trajektorie elektronového svazku na vlastnosti povrchu oceli 42CrMo4 / Influence of the electron beam trajectory on the surface properties of steel 42CrMo4

Mikuš, Tomáš January 2018 (has links)
The thesis deals with surface quenching of steel 42CrMo4 by electron beam. Influence of technologic parameters and beam deflection on properties and structure of prepared layers is studied. Electron beam surface quenching was applicated with and without melting of the surface. Structures of layers made by electron beam quenching were compared with structures made by laser and electromagnetic induction. Structures and phases were analysed by optical microscopy, SEM and roentgen diffraction. Hardness was measured on hardened layers.
18

Elektromagnetická kompatibilita výzbrojí tramvajových vozidel / Electromagnetic compatibility of tram equipment

Gavshin, Ruslan January 2021 (has links)
This diploma thesis deals with the issue of EMC of tram vehicles and traction system. The first chapter defines the issues that are then dealt with in the thesis. The next chapter lists the objectives of the work. Subsequent chapters analyze the issues described in chapter 2. In the last chapter, a flow chart is proposed, which should serve as a tool to estimate the hazards of the traction drive due to induced bearing currents.
19

Využití signálů elektromagnetické a akustické emise pro lokalizaci trhlin vznikajících při mechanickém zatěžování pevných látek / Application of electromagnetic and acoustic emission signals for localization of cracks generated during mechanical stressing of solids

Burděj, Václav January 2008 (has links)
Terms of acoustic emission (AE) and electromagnetic emission (EME) designated physical effects and also as diagnostic methods based on these effects. These effects are caused by generated cracks in materials that rank among non-destructive techniques of material diagnostics. The advantage of them is that they do not affect the measured object and give us information about the current dynamic state of a tested material. One disadvantage of these effects is that they provide very low energy of signal emissions and make it difficult for broader usage. It is expected better localization of cracks in non-conductive materials by connecting of these two techniques (diagnostics). There are designed and described new methods for crack detection with usage of AE and EME signals in this work. Also there is description of measuring arrangement intended of crack detection and experimental sample for checking accuracy of methods for crack detection. There was performed comparison of accuracy of methods in crack detection.
20

Optovláknový zdroj laserového záření / Fiber optic source of laser radiation

Fučík, Milan January 2013 (has links)
This master’s thesis deals with parameters and properties of electromagnetic wave, its spread in environment and then in optical fiber, as well with optical fibers. Principle of laser sources and a issues of coupling a optical performance into optical fiber are described here. Next a function of laser diodes, power and cooling requirements are described. A block diagram of fiber optic source of laser radiation is designed as well as a circuit solution of every single block with respecting of parameters and sensitivity of used laser diode. The protection of laser diode and high-frequency modulation of optical power are solved. Subsequently the construction of every single block was done and the right function of constructional solution was tested.

Page generated in 0.0735 seconds