Mechatronic Concepts of Automated Weather Radars (a survey)

AbstractQuantification of precipitation is currently an important factor for agriculture but also for flood forecasting. In meteorology there is a strong interest in automatic stations and in replacing manually operated precipitation gauges with automated ones. This article mainly deals with measuring precipitation using radar (Radio Detection and Ranging). Standard weather radars can measure precipitation in a large territory, but to measure the local precipitation a vertically pointing radar is more suited. These types of radars use the Doppler effect to measure the speed of falling drops. The article describes some existing radar units, which allow automatic measurement of the present local rainfall. The common principles and methods for measuring precipitation will also be shown

Path Planning with Modified a Star Algorithm for a Mobile Robot

AbstractThis article deals with path planning of a mobile robot based on a grid map. Essential assumption for path planning is a mobile robot with functional and reliable reactive navigation and SLAM. Therefore, such issues are not addressed in this article. The main body of the article introduces several modifications (Basic Theta*, Phi*) and improvements (RSR, JPS) of A star algorithm. These modifications are focused primarily on computational time and the path optimality. Individual modifications were evaluated in several scenarios, which varied in the complexity of environment. On the basis of these evaluations, it is possible to choose path planning method suitable for individual scenario

Departure from solid solution behavior in double perovskites

Mixed ionic electronic conducting oxides (MIEC) serve a plethora of electrochemical applications such as cathodes for solid oxide electrochemical cells and oxygen evolution reaction catalysts for water splitting. These applications rely to a large extent on the MIEC’s ability for electron and/or ion transfer across the solid/gas or solid/liquid interface. The efficacy of these reactions being governed by the surface defect chemistry and electronic structure, rational design of the (surface) chemistry presents itself as an auspicious path to tune these properties towards optimal device performance. Please click Additional Files below to see the full abstract

Phosphorus poisoning during wet oxidation of methane over Pd@CeO2/graphite model catalysts

10siThe influence of phosphorus and water on methane catalytic combustion was studied over Pd@CeO2 model catalysts supported on graphite, designed to be suitable for X-ray Photoelectron Spectroscopy/Synchrotron Radiation Photoelectron Spectroscopy (XPS/SRPES) analysis. In the absence of P, the catalyst was active for the methane oxidation reaction, although introduction of 15% H2O to the reaction mixture did cause reversible deactivation. In the presence of P, both thermal and chemical aging treatments resulted in partial loss of activity due to morphological transformation of the catalyst, as revealed by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) analysis. At 600 °C the combined presence of PO43− and water vapor caused a rapid, irreversible deactivation of the catalyst. XPS/SRPES analysis, combined with operando X-ray Absorption Near Edge Structure (XANES) and AFM measurements, indicated that water induces severe aggregation of CeO2 nanoparticles, exposure of CePO4 on the outer layer of the aggregates and incorporation of the catalytic-active Pd nanoparticles into the bulk. This demonstrates a temperature-activated process for P-poisoning of oxidation catalysts in which water vapor plays a crucial role.partially_openembargoed_20171009Monai, Matteo; Montini, Tiziano; Melchionna, Michele; Duchoň, Tomáš; Kúš, Peter; Tsud, Nataliya; Prince, Kevin C.; Matolin, Vladimir; Gorte, Raymond J.; Fornasiero, PaoloMonai, Matteo; Montini, Tiziano; Melchionna, Michele; Duchoň, Tomáš; Kúš, Peter; Tsud, Nataliya; Prince, Kevin C.; Matolin, Vladimir; Gorte, Raymond J.; Fornasiero, Paol

Set of Menace connected with Unemployment at Economic Crisis Time

This work is dedicated to the issue of impact of the economic crisis on the labour market. In this work I am in front of all dealing with the increase of unemployment during the economic crisis. I focus on the Rakovník region, in which I analyze the influence of the economic crisis on unemployment

Physically chemical properties of epitaxial films CeOx/Cu(111)

In this work a reversible transition between CeO2/Cu(111) and Ce2O3/Cu(111) was studied by metalic ceria evaporation and oxygen exposition. Prepared layers were characterised by XPS, ISS (and its angle resolved modification), LEED and XPD combined with computer modelling using EDAC code. Four reconstructi- on were identified within the transition - ( √ 7 × √ 7)R19.1◦ , ( √ 3 × √ 3)R30◦ , 3 × 3 and 4 × 4 - for which structural models were suggested. Prepared layers of Ce2O3/Cu(111) exhibiting the 4×4 reconstruction were identified as a cubic pha- se of Ce2O3 by the combination of all methods. The photoelectron spectroscopy study of the chemical state of layers revealed that reduction proceedes from the surface and oxidation is realised by oxygen diffusion into the volume

Competitive analysis of the hotel Dorint Don Giovanni

The Master's Thesis is focused to the issue of competitiveness in Prague four star hotel. The goal of this work is to make strategic competitior analysis, map the current trends affecting tourism and on the basis of the evaluation results to formulate proposals and recommendations to the hotel's management. This work uses the selected analytical methods to determine the future direction of the hotel and eliminating its shortcomings

Set of Menace connected with Unemployment at Economic Crisis Time

Bakalářská práce "Hrozba nezaměstnanosti v době hospodářské krize" se zabývá dopadem hospodářské krize na trh práce. V této práci se zabývám především nárůstem nezaměstnanosti v době hospodářské krize. Zaměřuji se na okres Rakovník, ve kterém analyzuji vliv hospodářské krize na nezaměstnanost v regionu.This work is dedicated to the issue of impact of the economic crisis on the labour market. In this work I am in front of all dealing with the increase of unemployment during the economic crisis. I focus on the Rakovník region, in which I analyze the influence of the economic crisis on unemployment

Photoelectron spectroscopy study of adsorption on sputtered ceria films prepared in-situ

During this work CeOx films were prepared by magnetron sputtering on a graphite foil and a monocrystalline silicon wafer. Samples were characterised by the method of x-ray photoelectron spectroscopy in situ and then exposed to effects of the atmosphere. Influences of substrate, target substrate distance and duration of sputtering on stoichiometry of prepared films were observed. It was found out, that exposition to atmosphere reduces prepared films. Reduction was higher on films prepared on graphite foil and sputtered from greater distance

Elektronické a strukturní vlastnosti modelových katalyzátorů na bázi oxidu ceru

Katalyzátory na bázi oxidu ceru jsou všudypřítomné v industriálních chemických pro- cesech. V této práci jsou studovány jejich základní vlastnosti skrze modelový přístup s cílem podpořit racionální vývoj v heterogenní katalýze. Práce se zaměřuje na porozumění chování kyslíkových vakancí v rámci atomární koordinace a poruch elektronové struktury. S využitím moderních experimentálních technik je vyvinuta škálovatelná soustava mode- lových systémů, která umožňuje kontrolu koncentrace kyslíkových vakancí a jejich lokální koordinace. Vysoká přesnost tohoto inovativního přístupu umožnila pozorování nových fázi nestoichiometrického oxidu ceru a vedla k první studii elektronové struktury oxidu ceru v průběhu izostrukturního přechodu od CeO2 k Ce2O3. Získané výsledky představují pokrok v porozumění základním vlastnostem oxidu ceru ve vztahu k jeho využití v heterogenní katalýze a otevírají nové cesty k funkcionalizaci materiálů na bázi oxidu ceru. Metodologie vyvinutá v rámci této práce je navíc snadno přenositelná na další důležité reducibilní oxidy. 1Catalysts based on cerium oxide are ubiquitous in industrial-scale chemical conversion. Here, a thorough study of their fundamental properties is undertaken via a model system ap- proach with the goal of furthering rational design in heterogeneous catalysis. A focus is put on understanding the behavior of oxygen vacancies in cerium oxide with respect to atomic co-ordination and electronic structure perturbations. Utilizing state-of-the-art probing tech- niques, a scalable model system framework is developed that allows for control over both the oxygen vacancy concentration and local co-ordination. High precision of the innova- tive approach facilitated observation of new phases of substoichiometric cerium oxide and lead to a first-of-a-kind investigation of the electronic structure of cerium oxide throughout isostructural transition from CeO2 to Ce2O3. The acquired results advance fundamental understanding of essential properties of cerium oxide that are relevant to its utilization in heterogeneous catalysis and open new pathways for functionalization of cerium oxide-based materials. Furthermore, the methodology developed in the thesis is transferable to other important reducible oxides. 1Katedra fyziky povrchů a plazmatuDepartment of Surface and Plasma ScienceMatematicko-fyzikální fakultaFaculty of Mathematics and Physic