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Diagnostics of electric discharges in liquids
Vašíček, Michal ; Mazánková, Věra (referee) ; Kozáková, Zdenka (advisor)
The main scope of this thesis is to measure electrical characteristics of a DC discharge in an electrolyte solution in order to evaluate individual discharge parameters (voltage, current, emitted light and sound). As a result of these parameters, a comparison between a diaphragm and capillary configuration has been realized using static and dynamic characteristics. Next part of this thesis is finding mutual differences and to set an approximate transition of individual configurations. For the study of the pin-hole discharge a polycarbonate reactor with total volume of 110 ml was used. It was divided by a changeable polyacetal insulating wall. The Shapal ceramic discs (thickness of 0.3–1.5 mm and diameter of the central pin-hole of 0.3 mm) were mounted in the centre of the insulating wall. This wall divided the reactor into two approximately equal spaces with one stainless steel electrode in each part. A DC high voltage source providing constant power supply up to 500 W was applied on the electrodes. The water solution of NaCl with initial conductivity of 570 S/cm was used as electrolyte. Time resolved electrical characteristics were recorded by a four channel oscilloscope Tektronix TDS 2024B. Measured parameters were as follows: voltage (by a HV probe Tektronix P6015A), current at ballast resistor of 5.13 , sound detected by a piezzo-microphone mounted under the reactor, and light emitted by the discharge was detected by an optical fiber in vicinity of the orifice. Measuring and processing of time resolved electrical characteristics present an accurate description of behavior of the diaphragm and capillary configuration. Voltage differences during the phase of bubble formation as well as around the breakdown point were discussed. This thesis contains a description of bubble cavitation and sets transition ratio between the diaphragm and capillary configuration approximately to l/d= 3 (where l is thickness of the wall and d is diameter of the pin-hole).
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Plasma diagnostics of electric discharges generated in selected configurations in liquids
Vašíček, Michal ; Bartlová, Milada (referee) ; Kozáková, Zdenka (advisor)
My diploma thesis is focused on a comparison of direct-current and high frequency (15-80 kHz) electric discharge, which generates non-thermal plasma in water solution of sodium chloride. Mainly current-voltage and Lissajous charts are discussed in the first part of this thesis. These charts describe different discharge phases: electrolysis, bubble formation, discharge breakdown and discharge regular operation in a pin-hole of a dielectric barrier. Influence of frequency, electrolyte conductivity, thickness of the diaphragm (or length of the capillary) and pin-hole diameter on discharge breakdown and bubble generation was studied, too. Measurements were realized in a polycarbonate reactor with total volume of 110 ml, which was divided by a changeable polyacetal insulating wall. This wall divided the reactor into two approximately equal spaces with one stainless steel planar electrode in each part. The Shapal-MTM ceramic discs (thickness of 0.3–1.5 mm and diameter of the central pin-hole of 0.3-0.9 mm) were mounted in the centre of the insulating wall. Initial conductivity of sodium chloride solution was chosen within the interval of 100900 S/cm. The second part of my thesis compares an influence of the direct-current (DC) and high frequency (HF) power sources on physical solution properties (conductivity, pH and temperature) and generation of hydrogen peroxide. A plasma reactor with total volume of 4 l and with mixing set up was divided into two equal spaces with one planar platinum electrode in each part. Diaphragm with thickness of 0.6 mm and pin-hole diameter of 0.6 mm was installed in the middle of the separating wall. Experiment was held at discharge operation of 45 W for 40 minutes with both power sources. Detection of hydrogen peroxide was realised by using a titanium reagent forming a yellow complex, which was analysed by absorption spectroscopy. If HF discharge power is plotted as a function of applied frequency, exponential decrease of frequency with increasing power can be observed. Higher breakdown voltage is necessary for thicker dielectric barriers, on the other hand for bigger diameter of the pin-hole lower breakdown voltage and higher power is needed in DC as well as in HF regime. Breakdown voltage is decreased by the increasing conductivity in both regimes; due to more charge carriers in the higher conductivity lower breakdown voltage is needed. However frequency in HF regime and DC discharge power increases. HF discharge power is decreased by the increasing conductivity. Solution conductivity and temperature are increased by initial conductivity value in both discharge regimes. Solution pH drops to acidic conditions when HF or DC positive regime is applied due to the generation of reactive species and electrolysis (in DC regime). However solution becomes alkaline when DC negative regime is applied. Concentration of hydrogen peroxide is produced linearly when HF or DC negative regime is applied and it depends on initial solution conductivity.
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Proposal for Company Financial Plan
Douchová, Tereza ; Vašíček, Michal (referee) ; Karas, Michal (advisor)
The master’s thesis focuses on the draft financial plan of the company. The first part of the thesis focuses on the theoretical basis of financial planning. The next part is focuses to introduction of selected company and business analysis at present. Subsequently, the company’s financial plan for the years 2016 - 2018 is proposed in two variants. The last part of the thesis is an evaluation of the company’s financial plan.
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The dynamics of the development of Ruthenian dialects in Slovakia and Ukraine as exemplified by prepositions
Vašíček, Michal
This article deals with the dynamics of the vocabulary of Ruthenian dialects in two regions of two states – eastern Slovakia and Transcarpathia in Ukraine. It focuses on prepositions as well as conjunctions and particles, which are function words with a high frequency of occurrence. The analysis is based on dialectal material obtained during our own field research, carried out since 2011 in this area, specifically in the municipalities of Ubľa and Malyj Bereznyj, lying close to the Slovak-Ukrainian state border. Here, until World War II closely related Ruthenian dialects had been evolving in sociolinguistically identical conditions. But after World War II, they were separated by the Czechoslovak-Soviet border and came under the influence of different literary languages – Slovak, on the one side, and Ukrainian and Russian on the other. Due to levelling processes oriented to different literary languages, the originally closely related dialects have considerably diverged from each other. Comparing the current material with older dialectal materials, we will try to document more recent influences of literary languages on the development of Ruthenian dialects.\n
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The dynamics of Southern Carpathian dialects
Vašíček, Michal ; Giger, Markus (advisor) ; Rabus, Achim (referee) ; Dudášová, Júlia (referee)
The dynamics of Southern Carpathian dialects - abstract The aim of this work is to describe the development of Southern Carpathian dialects in two state entities, in northeastern Slovakia and the Transcarpathian region of Ukraine, in the last 70 years. Starting material are recordings of dialectal speech and their transcription obtained in own field research conducted since 2011 within the studied area, especially in villages located close to the Slovak-Ukrainian state border. The focus of this work is a description of the dynamics of the phonetic, morphological and lexical system of the dialects of two villages, Ublya, which was chosen due to the long tradition of dialect research, and Malyi Bereznyi, the nearest neighboring village on the territory of Ukraine. Here until World War II closely related Southern Carpathian dialects had been developing in the same sociolinguistic conditions. After World War II they were separated by the Czechoslovak- Soviet border and came under the influence of different standard languages - Slovak, on the one hand, and Ukrainian and Russian on the other hand. A comparison of older material with the results of our field research enables to observe a dialectal divergence caused by leveling processes oriented to different standard languages. Data obtained in Ublya and Malyi...
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Proposal for Company Financial Plan
Douchová, Tereza ; Vašíček, Michal (referee) ; Karas, Michal (advisor)
The master’s thesis focuses on the draft financial plan of the company. The first part of the thesis focuses on the theoretical basis of financial planning. The next part is focuses to introduction of selected company and business analysis at present. Subsequently, the company’s financial plan for the years 2016 - 2018 is proposed in two variants. The last part of the thesis is an evaluation of the company’s financial plan.
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The Lachian of Óndra Łysohorsky as a Microlanguage. Morfological Analysis.
Vašíček, Michal ; Marvan, Jiří (advisor) ; Čermák, Václav (referee)
Diploma thesis "The Lachian of Óndra Łysohorsky as a Microlanguage" deals with literary lachian, a microlanguage, created by the poet Óndra Łysohorsky (own name Ervin Goj) and based on the upper Ostravice dialects. This language should be an attempt to create a new standard language for speakers of lachian dialects. However, the broader public did not accept it and with the exception of a short period at the end of the 30th years of the 20th century Óndra Łysohorsky was the only person, who wrote poems in lachian. It is therefore rather unique poetic idiolect. The language of Łysohorsky's poetry has not yet been explored in detail, systematic grammatical descriptions are completely lacking. The aim of this thesis is to provide a description of the morphology of this unique linguistic phenomenon. For this purpose it was created the lachian language corpus, which contains the vast majority of lachian poetic texts. A language corpus allows a more detailed elaboration of the language material, therefore it was possible to try to sort grammatically all the vocabulary of literary lachian. Each of the paradigmatic types is followed by the list of all the words (which we can determine) inflected according to this declination or conjugation model. Besides the morphological description the thesis tries to...
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National consciousness of Southern-Carpathian dialect speakers in the Slovak-Ukrainian border area
Vašíček, Michal
This paper aims to analyze the current national identification of East-Slavic dialect speakers in Slovakia and compare it with the national attitudes of Slavic inhabitants on the territory of the Transcarpathian region of Ukraine. Among the representatives of East-Slavic ethnic group in the Slovak Republic the ethnonym Rusnak predominates, while in Ukraine the majority of informants consider themselves to be Ukrainians or Rusyns. Seventy-year existence of the political border between Czechoslovakia and USSR and then between Slovakia and Ukraine has greatly influenced not only the development of the local East-Slavic dialects, but also the national consciousness of their speakers.
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Plasma diagnostics of electric discharges generated in selected configurations in liquids
Vašíček, Michal ; Bartlová, Milada (referee) ; Kozáková, Zdenka (advisor)
My diploma thesis is focused on a comparison of direct-current and high frequency (15-80 kHz) electric discharge, which generates non-thermal plasma in water solution of sodium chloride. Mainly current-voltage and Lissajous charts are discussed in the first part of this thesis. These charts describe different discharge phases: electrolysis, bubble formation, discharge breakdown and discharge regular operation in a pin-hole of a dielectric barrier. Influence of frequency, electrolyte conductivity, thickness of the diaphragm (or length of the capillary) and pin-hole diameter on discharge breakdown and bubble generation was studied, too. Measurements were realized in a polycarbonate reactor with total volume of 110 ml, which was divided by a changeable polyacetal insulating wall. This wall divided the reactor into two approximately equal spaces with one stainless steel planar electrode in each part. The Shapal-MTM ceramic discs (thickness of 0.3–1.5 mm and diameter of the central pin-hole of 0.3-0.9 mm) were mounted in the centre of the insulating wall. Initial conductivity of sodium chloride solution was chosen within the interval of 100900 S/cm. The second part of my thesis compares an influence of the direct-current (DC) and high frequency (HF) power sources on physical solution properties (conductivity, pH and temperature) and generation of hydrogen peroxide. A plasma reactor with total volume of 4 l and with mixing set up was divided into two equal spaces with one planar platinum electrode in each part. Diaphragm with thickness of 0.6 mm and pin-hole diameter of 0.6 mm was installed in the middle of the separating wall. Experiment was held at discharge operation of 45 W for 40 minutes with both power sources. Detection of hydrogen peroxide was realised by using a titanium reagent forming a yellow complex, which was analysed by absorption spectroscopy. If HF discharge power is plotted as a function of applied frequency, exponential decrease of frequency with increasing power can be observed. Higher breakdown voltage is necessary for thicker dielectric barriers, on the other hand for bigger diameter of the pin-hole lower breakdown voltage and higher power is needed in DC as well as in HF regime. Breakdown voltage is decreased by the increasing conductivity in both regimes; due to more charge carriers in the higher conductivity lower breakdown voltage is needed. However frequency in HF regime and DC discharge power increases. HF discharge power is decreased by the increasing conductivity. Solution conductivity and temperature are increased by initial conductivity value in both discharge regimes. Solution pH drops to acidic conditions when HF or DC positive regime is applied due to the generation of reactive species and electrolysis (in DC regime). However solution becomes alkaline when DC negative regime is applied. Concentration of hydrogen peroxide is produced linearly when HF or DC negative regime is applied and it depends on initial solution conductivity.
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