Software-Defined Optics

Tato bakalářská práce se zabývá současným stavem problematiky komunikace viditelným spektrem světla. V první části je popsána komunikace viditelným světlem a rozbory modulací OFDM a FBMC. Následně je popsán standard IEEE 802.15.7. V praktické části je prováděno měření bitové chybovosti BER a testování limitů LED svítidla. Toto měření je prováděno uvnitř budovy, při měření bitové chybovosti v závislosti na šířce frekvenčního pásma a vzdálenosti od světelného zdroje a použitého modulačního schéma.This bachelor thesis deals with the current state of communication with visible light spectrum. The first part describes visible light communication and analyzes of OFDM and FBMC modulations. Then the IEEE 802.15.7 standard is described. In the practical part, the measurement of BER error rate and testing of LED luminaire limits is performed. This measurement is performed indoors, when measuring the bit error rate depending on the frequency bandwidth and the distance from the light source and the modulation scheme used.440 - Katedra telekomunikační technikyvýborn

Analysis of non-metalic inclusions in motor heads castings and suggestion on their remove

Zlepšování kvality kovu pro sériovou výrobu odlitků automobilového průmyslu vede ke zkvalitňování vlastností odlitků a k jejich nižším výrobním nákladům. Tato práce se zabývá analýzou nekovových vměstků obsažených v odlitcích hlav spalovacích motorů, odlévaných ve společnosti Nemak Czech Republic, s.r.o. Řešení problematiky obsahuje rozbor velikostí, tvarů, chemického složení a tvrdostí konkrétních nekovových vměstků. Dále se práce zabývá popisem čistoty kovu v udržovacích pecích a návrhem na odstranění vměstků z kovu.Improving the quality of metal castings for serial production of automotive industry, leading to improvements in the properties of casts and their lower costs. This publication analyzes the non-metallic inclusions contained in casts of heads of internal combustion engines, molded of Nemak Czech Republic, Ltd. Tackling includes analysis of size, shape, chemical composition and hardness of the specific non-metallic inclusions. The thesis describes the purity metal holding furnaces and proposals to eliminate inclusions from metal.

SDR-Based FPGA System for V2X-VLC Communications

Diplomová práce se zabývá současným stavem problematiky komunikace viditelným světlem mezi vozidly. Práce je rozdělena na dvě hlavní části, přičemž první část slouží jako popis V2X-VLC komunikace a rešerše k vybraným experimentům s důrazem na využití V2X-VLC. Druhá část je praktická, ve které jsou prováděny měření s využitím předního světlometu na automobilu.The master thesis deals with the current state of the visible light communication between vehicles. The thesis is divided into two main sections, with the first section serving as a description of V2X-VLC communication and a review of selected experiments with emphasis on the use of V2X-VLC. The second section is practical, in which in which measurements are carried out using the headlight on the car.440 - Katedra telekomunikační technikyvýborn

Water soluble foundry binders with heat hardening

Se stoupajícími požadavky na slévárenství jsme nuceni vyvíjet nové druhy slévárenských pojiv ať už organických či anorganických. Existuje celá řada požadavků na formovací směsi, pro správnou funkci. Formovací směsi musí vykazovat vhodné technologické, ekonomické a navíc ekologické vlastnosti. Mnoho ekologicky závadných odpadů vzniká z organických látek obsažených převážně v pojivech a katalyzátorech používaných pro formovací směsi. Dobrým uplatněním tedy mohou být vodou rozpustná pojiva vytvrzovaná teplem. Tyto pojiva umožňují snadné a rychlé zpracování a obnovitelnost směsí.With the increasing foundry requirements we are forced to develop new kinds of foundry binders, either organic or inorganic. There are several requirements for the molding composition and for the proper function. The sand mixture must exhibit appropriate technological, economic and also ecological characteristics. Many environmentally harmful wastes are created from the organic substances contained mainly in binders and catalysts used for molding of the mixture. A good application can be the water-soluble binder cured by heat. These binders allow easy and fast processing and a mixture recoverability.

Temperature and Resource Availability May Interactively Affect Over-Wintering Success of Juvenile Fish in a Changing Climate

The predicted global warming may affect freshwater systems at several organizational levels, from organism to ecosystem. Specifically, in temperate regions, the projected increase of winter temperatures may have important effects on the over-winter biology of a range of organisms and especially for fish and other ectothermic animals. However, temperature effects on organisms may be directed strongly by resource availability. Here, we investigated whether over-winter loss of biomass and lipid content of juvenile roach (Rutilus rutilus) was affected by the physiologically relatively small (2-5°C) changes of winter temperatures predicted by the Intergovernmental Panel on Climate Change (IPCC), under both natural and experimental conditions. This was investigated in combination with the effects of food availability. Finally, we explored the potential for a correlation between lake temperature and resource levels for planktivorous fish, i.e., zooplankton biomass, during five consecutive winters in a south Swedish lake. We show that small increases in temperature (+2°C) affected fish biomass loss in both presence and absence of food, but negatively and positively respectively. Temperature alone explained only a minor part of the variation when food availability was not taken into account. In contrast to other studies, lipid analyses of experimental fish suggest that critical somatic condition rather than critical lipid content determined starvation induced mortality. Our results illustrate the importance of considering not only changes in temperature when predicting organism response to climate change but also food-web interactions, such as resource availability and predation. However, as exemplified by our finding that zooplankton over-winter biomass in the lake was not related to over-winter temperature, this may not be a straightforward task

A Liquid Crystal-Switched Passive Van Atta Array Element for Millimetre-Wave Automobile Radar Target Enhancement and Concurrent Data Modulation in Adverse Weather Conditions

Severe weather challenges drivers by degrading visibility and road conditions. Modern automotive collision avoidance systems also experience degraded performance in bad weather, which reduces the range of car-mounted sensors that detect obstacles on the road, and of communication networks that warn other cars about hazards. Radar systems are resistant to most weather but remain affected by heavy rainfall, due to regulatory constraints on frequency and power. Radar architectures can improve, but this thesis proposes to enhance the detectability of vehicles by increasing their radar cross sections with a new automotive safety device: a conformal retrodirective patch antenna array installed into car bodywork. A millimetre-wave array element with a novel liquid crystal switch is successfully simulated, fabricated, and experimentally shown to sufficiently modulate the retransmitted radar signal to piggyback data. This guarantees safe detection ranges in worst-case rain showers and replaces secondary communication systems, minimizing environmental RF pollution