National Repository of Grey Literature 11,537 records found  beginprevious11528 - 11537  jump to record: Search took 0.30 seconds. 

Human powered electric sources
Naller, Ivan ; Škoda, Jan (referee) ; Baxant, Petr (advisor)
The aim of this work is to map sources of electricity-driven man. It is divided into three parts, the first of which deals with the muscles of the human body and essential components of the diet. The second part includes a search created prototypes of generators from small to big achievements. The last part is focused on the performance that can be achieved in a given individual and the associated energy demands of humanity. After the experiment, it is apparent that the average power of man is in the range of 150 to 300 W. On the basis of the data obtained it is possible to use the energy generated man (in gyms, fitness centers ....) for lighting, or simple applications such as water heating etc.

Switzerland and its attitude towards the european integration
Šrámková, Eva ; Steinmetzová, Dana (advisor) ; Popovová, Marie (referee)
The aim of this thesis is to analyse and to asses the reasons and causes of the Swiss attitude towards the european integration and to adumbrate the future development of this attitude with regard to the future development of the relations between EU and Switzerland during the economic crisis. The thesis is divided into three chapters. The first chapter characterises Switzerland politically a economically. It emphasises the influence of the direct democracy and political parties on government decisions. It describes the Swiss economy in light of macroeconomic indicators, then the sectors of economy, Swiss balance of payments and especially the foreign trade and the trading relations to the EU including the commodity structure. The second chapter deals with the main reasons of the negative attitude of Switzerland towards the regional integrations, characterises Switzerland as a member of the EFTA and focuses on the actual development of the bilateral relations to the EU. The third chapter describes the effects of the financial crisis on the Swiss economy and its impact on the future development of the relations to the EU.

Electrical Trauma
Werner, Petr ; Königová, Radana (advisor)
While energy flash terrified humanity for thousands of years of history, electricity produced by man serve humanity but also threatening , since 1879 , when Thomas Alva Edison discovered the electric light . its system delivery and use of energy was direct current , which is not suitable for high voltage power transmission over long distance. In 1885, he demonstrated another discovery . George Westinghouse has developed a system using alternating current transformers, which are designed to increase the voltage on the one hand and transmission distribution of energy, and reduce stress on energy consumption. ten years lasted feud between advocates of direct and alternating current, which was ended up using alternating current to Niagara Falls in 1895 and for execution by electric chair in 1900. Passing a current through each wire heats up. electrical work made to the current passes through a conductor , all converted into heat. losses thermal energy is proportional to the resistance wire and increases the second square of the current . Therefore, it is advantageous when high energy performance over long distances transmit energy high voltage at low current in the line. With increasing demands on energy was necessary to develop appropriate preventive measures and technical security, as well as improved methods...

Fine set-up of the Ar-Ion laser and fibre loader
Konfršt, Jiří ; Kysela, Bohuš ; Chára, Zdeněk
Use of lasers in the measuring systems, which use LDA/PDA devices, expects good knowledge of physical characteristics of used light source namely for multicomponent measurements. This article is focused on the experimental parameter analysis of individually separated light wavelength from Ar-Ion plasma tube, working in multiline “ML” mode. The best laser source parameters: aperture size, power input and quality of the utilized separate wavelengths were obtained and beams were adjusted to the optical fibres.

Wireless System for Evaluation of Lighting Control in Buildings for Obtaining Information Leading to Savings
Malinowski, Radim ; Korček, Pavol (referee) ; Strnadel, Josef (advisor)
The aim of the thesis is to design a system based on wirelessly comunicating devices that will be able to record an information about persons presesce in certain area. Aquired data will served for evaluation of the area lighting system efficiency. Partial goals related to this work are: to analyze electricity consumption mesaurement methods, to analyze presence and movement detection methods, to analzye wireless communication methods, to desin system's HW and SW including realization, to put system into a real operation and finally, to evaluate measured data.

Blaze Gratings with a Ribbed Back Slope
Krátký, Stanislav ; Meluzín, Petr ; Horáček, Miroslav ; Kolařík, Vladimír ; Matějka, Milan ; Chlumská, Jana ; Král, Stanislav
Binary relief phase-modulated gratings provide symmetrical diffraction of the incoming light beam. Asymmetrical gratings, e.g. asymmetrical triangular blazed gratings, are characteristic by an asymmetrical diffraction behavior, where one of the first diffraction orders is more important than the other one. Electron beam lithography is a suitable and flexible tool for patterning of such kind of gratings. High quality results can be readily obtained when the period of the grating is relatively large and the relief depth is relatively low, this is the case of gratings with a small blaze angle. As the blaze angle increases, the quality of result suffers from several patterning-related issues. One of the problems is a reflection of the incoming light beam from the back slope (anti-blaze facet) of the blaze grating. We propose a novel configuration, with a ribbed modulation of the back slope. This modulation is perpendicular to the direction of the grating grooves. This paper presents an analysis of the proposed blazed grating configuration. E-beam pattern generators were used to prepare a few\nsamples of blaze gratings with a ribbed back slope. One part of the experiment was performed with a Gaussianshaped beam and another one with the variable-shaped beam. Results of the experiment are presented.\nFinally, we discuss the optical performance of two blaze gratings with similar parameters, one of them is with the flat back slope and another one is with the ribbed back slope.

Device calibration.
Melich, Radek ; Václavík, Jan ; Žídek, Karel
The device has to be calibrated in absolute terms for its brightness response. This will be facilitated by a combination of an integrating sphere and collimating objective. The emitted total light intensity will be controlled by a reference photodiode inside the integrating sphere.

Measurement of camera spectral response
Melich, Radek ; Václavík, Jan ; Žídek, Karel
Spectral response of the camera will be measured using monochromator in conjunction with an integration sphere. Camera without objective will be placed in one port of the integrating sphere and light beam from monochromator will be fed into perpendicular port. Sensor of the camera sensor will be therefore uniformly illuminated by diffused light from monochromator. Proposed FWHM of the monochromator is 15 nm as a trade-off between light intensity provided by monochromator and deformation of spectral characteristic (Picture XY). Diameter of the integrating sphere has to be larger than 100 mm to ensure uniform illumination over sensor area.

Portable and Miniaturized Separation Techniques Applicable for Food and Biotechnology Analysis
Dvořák, Miloš ; Pospíchal, Jan (referee) ; Bednář,, Petr (referee) ; Rittich, Bohuslav (advisor)
Capillary electrophoresis was used for determination of 6 fractions of caseins. Those fractions were measured in 144 samples of cow’s milk originated from the feeding experiment focused on explanation the influence of the feeding onto casein productions. In this work were separated 6 fraction of caseins first time with total resolution of the peaks. Capillary electrophoresis was applied for determination of short-chain organic acids during fermentation of wine must. It was compared the fermentation of must fermented by different yeast. The difference of profile short-chain organic acids during fermentation were not statistically significant. The once difference was in the utilisation of the malic acid and production of the lactic acid. A portable miniaturized system for medium pressure liquid chromatography was developed. The components were tested and system was used for the isocratic and gradient elution of various analytes (food dyes, parabens). New line of electroluminescent diodes (LEDs) for deep-UV areas of wavelength based on a different materials substrate was characterised. The new line was compared with old line LEDs. The new line LEDs was incorporated in deep-UV absorbance detectors. Detectors were characterised and tested for a detection various analytes in modes flow injection analysis and chromatography separation. First time was characterised this new line of the LEDs and the origin of the parasitic emission band produced by deep-UV LEDs light sources was explained. This origin is given by disturbances of a materials substrates. This work is a contribution for an advance of low-cost and portable systems and detection devices in the field of analytical chemistry.

Spectroscopic Study of Underwater Electrical Discharge Generated by Nanosecond Pulses.
Pongrác, Branislav ; Šimek, Milan ; Babický, Václav ; Člupek, Martin ; Lukeš, Petr
Underwater electrical discharge generated by high voltage pulses with nanosecond duration (~110 kV amplitude on the needle, ~5 ns duration (FWHM), 1 Hz repetition rate) has been investigated. Time–resolved optical emission spectroscopy showed different emission spectra profile of the ns–pulsed discharge compared to the μs–pulsed discharges investigated previously. Some characteristic peaks typical for water discharges (Hα, OI) were clearly visible in the spectra. In addition, the integral light emission of the discharge was recorded by photomultiplier tube.