Organization of beach volleyball and beach football - Summer-Winter Escape

Bakalářská práce se zabývá vytvořením projektu turnaje Summer Winter Escape.Práce je rozdělena do dvou částí. První, teoretická část, vymezuje pojmy a definice, které souvisí s daným tématem a jež vychází z odborné literatury a zjištěných informací. Tyto pojmy se týkají marketingu, managementu, ale i projektového managementu. V praktické části je nejprve provedena analýza společnosti a návrh na zlepšení propagace. Poté se práce zabývá vytvořením projektu turnaje v beach volejbale a plážovém fotbale. V závěru jsou předložena opatření ke zlepšení projektu.The objective of this bachelor's thesis is to create a project for an upcoming tournament organized by Summer Winter Escape. The thesis is divided into two parts. The first part is theoretical, and it is focused on terms and definitions related to the topic, which are based on specialized literature and verified information. These terms and definitions concernmarketing, management and project management. The practical part consists of an analysis of the association Summer Winter Escape, and an improvement proposal for propagation.Another point of this part is to create a project for a tournament in beach volleyball and beach football. In the conclusion of the thesis submitted measures for improvement the project

The longest common subsequence problem a finite automata approach

A new algorithm that creates a common subsequence automaton for a set of strings is presented. Moreover, it is shown that a longest common subsequence of two strings over a constant alphabet can be found in φ (|A|(|S1| + |S2| + Σa∈A|S1|a|S2|S 2|a)) time, where |A| is the size of the alphabet, |Si| is the length of the input string i, and |Si|a is the number of occurrences of a ∈ A in Si.</p

Two-dimensional pattern matching by two-dimensional online tessellation automata

A new method that transforms a special type of non-deterministic two-dimensional online tesselation automata into deterministic ones is presented. This transformation is then used in a new general approach to exact and approximate two-dimensional pattern matching based on two-dimensional online tessellation automata that generalizes pattern matching approach based on finite automata well known from one-dimensional case.</p

A new protocol for the identification of singlet fission sensitizers through computational screening

Although singlet fission presents deep advantages or the generation of solar energy, the list of efficient singlet fission sensitizers is still very short, encouraging the theoreticians to focus their efforts on selecting and designing new candidates. Here, it is presented a computational protocol for the efficient screening of databases to select those species matching the energy requirements for singlet fission. Hence, out of the initial 29,123 species, 254 molecules (0.87%) were found to match singlet fission energy conditions. The consideration of practical concerns such as availability or stability reduced the number to just 24 (0.08%), among which the aminoanthraquinone derivatives are found particularly promising. The proposed protocol correct the deficiencies of the preceding ones, reaching DFT accuracy and minimizing the risk of getting false negatives especially at the early stages of the screening. In addition, this protocol can be used in future high-throughput investigations using datasets composed of millions of species.</p

Ab initio description of nanodiamonds: A DFT and TDDFT benchmark

In this article 15 DFT functionals were evaluated in order to find a good description of the electronic features and geometries of the nanodiamonds. With this in mind, two sets of molecules were designed, one of them composed by well-known organic molecules and other by diamondoids. The main parameters considered for comparison in this work are the excitation energies, ionization potentials, and the energies of the frontier orbitals. Moreover, absorption distances and binding energies were also considered to assess the quality of the description of the physisorption process. The best overall performance was found on hybrid functionals and more specifically on those with low HF percentage (TPSSH and O3LYP), despite reasonable results with lower computational cost can be obtained with GGA or LDA methods. The use of a correction for the dispersion interaction is mandatory except when a Truhlar functional, LDA or ωB97X functional is used. An augmented triple zeta basis set is recommended, especially for the description of the nanodiamond model, while an augmented double zeta is enough to yield a converged geometry.</p

On magnetic fluid particles dynamics investigation

This paper deals with the investigation of the dynamics of magnetorheological fluid. The response of ferromagnetic particles to changes in external magnetic field is observed with the use of high speed camera. Optically obtained data are processed with the use of scientific tool ImageJ. Functions and limit values of the particles dynamics are determined with the use of statistic methods afterwards

Tribological behaviour of Mo-S-N solid lubricant coatings in vacuum, nitrogen gas and elevated temperatures

Molybdenum disulphide (MoS2) is well known for the exceptional tribological properties in inert and high vacuum environments. On the other hand, these properties rapidly degrade in humid and higher temperature (&gt;300 °C) environments which cause increase of the friction coefficient and substantial increase of the wear. Apart from this, MoS2 films also suffers of porous structure, very low hardness and low load-bearing capacity which limits its applications in terrestrial atmosphere and more demanding conditions. Mo-S-N coatings published in previous studies revealed greatly improved mechanical and tribological properties in humid environment – low coefficient of friction, very low wear rates and one order of magnitude higher hardness. However, to this date, knowledge about sliding response of these Mo-S-N coating is mainly limited to humid air. In this work, we tested Mo-S-N coatings with different nitrogen contents from 0 to 40 at.% of N in vacuum (10−2 Pa), nitrogen atmosphere and elevated temperatures. The coatings were deposited by High Target Utilisation Sputtering method. All tribological tests were performed using ball-on-disc testing rig. A maximum hardness of 8 GPa was measured for the 19 and 31 atomic % N-doped coatings. In all testing conditions, the pure MoS2 films had COFs in the range of 0.02–0.15 and wear rates of 1.2–22×10−6 mm3N−1 m−1. The COF and specific wear rates decreased with N additions. Mo-S-N films had COFs between superlubric 0.007 and 0.13 and wear rates of 0.08–3×10−6 mm3N−1 m−1. The best overall tribological performance was shown to be for the Mo-S-N films containing 31 at.% of N. This study concluded that Mo-S-N coatings performed better than MoS2 in all testing conditions.</p

Revisiting the electronic nature of nanodiamonds

Nanodiamonds, commonly described as fragments of diamond, have been theoretically found to have lower HOMO-LUMO energy splitting compared to the bandgap of bulk diamond. This apparent lack of correlation between theory and experiment is caused by the position of the LUMO, which is placed in the surface of the ND. An eventual enlargement of the ND towards a macroscopic size will turn the LUMO into the unoccupied surface states, which are not accounted if the bandgap of a bulk material is measured. Here, the electron structure of the nanodiamonds is evaluated, demonstrating that due their nature they should be described as discrete systems instead of bulk materials. Hence, the word bandgap should be avoided in the case of the nanodiamonds, using HOMO-LUMO gap instead. Additionally, our obtained ionization potentials show a satisfactory degree of correlation with the experiment, while the electron affinities are found to be positive. Although this feature fits the estimation performed from experimental data, it opposes the generally accepted idea of a negative electron affinity for hydrogenated nanodiamonds. The present article clarifies common misunderstandings regarding the electronic nature of the NDs, and provides some guidelines for the correct computation of this systems. Finally, as a helpful tool, an estimation of the content of carbon atoms and its surface to volume ratio is provided starting from the diamond unit cell.</p

Structure, mechanical and tribological properties of Mo-S-N solid lubricant coatings

Solid lubricant coatings deposited by plasma-assisted deposition techniques represent modern way to reduce the coefficient of friction in lubricant-free sliding contacts. Molybdenum disulphide (MoS2 ) is perhaps the most known and applied solid lubricant coating; however, its use is strictly limited by low hardness and environmental sensitivity. To improve mechanical and tribological properties, we doped MoS2 coating with nitrogen. Mo-S-N self-lubricant films were deposited by pulsed d. c. High Target Utilisation Sputtering (HiTUS) in reactive atmosphere. The effect of deposition conditions on chemical composition, structure and mechanical properties of MoSx and Mo-S-N coatings was studied; films with the most promising properties have been selected for tribological testing. MoSx film with the elemental composition sulphur to molybdenum (S/Mo ratio) 1.6 exhibited the coefficients of friction (COFs) in humid air 0.17 and 0.07 for loads 2 and 15 N, respectively. Mo-S-N films were prepared with nitrogen content in a range of 11 to 50 at., whereas S/Mo ratio varied from 1.35 to 0.4. Mo-S-N films were amorphous or nanostructured with nanograins of molybdenum disulphide. Hardness increased with N content up to 14 GPa for film with the highest content of nitrogen. Friction behaviour in humid air was evaluated using a ball-on-disk tribometer. Globally, the doping with N resulted in hardness in Mo–S–N films one order of magnitude higher and wear rate two orders of magnitude lower than in an undoped one, keeping the friction coefficient at the same level or even lower. These coatings showed remarkable friction coefficients in humid air from 0.28 to 0.05 with loads from 2 to 15 N, respectively. The excellent friction properties were attributed to the formation of a thin molybdenum disulphide tribofilm at the sliding interface. HiTUS represents a very promising way of producing thin films on the thermally sensitive substrates (e.g. bearing steel) with desired properties. </p