|
|
Analysis of the Josephson junction phase dynamics with machine learning techniques
Jurčík, Róbert ; Žonda, Martin (advisor) ; Čermák, Petr (referee)
In this master's thesis, we provide a brief introduction to Josephson junctions and machine learning algorithms. We analyze the phase dynamics of Josephson junctions, notable for their significant second harmonic in the current-phase relationship. Initially, we generate data by simulating stochastic dynamics. We then investigate two aspects: determining occupation probabilities from the distribution function and detecting and categorizing anomalies (phase jumps) in a velocity spectrum. We determine that the random forest algorithm is the most effective model for calculating occupation probabilities from distribution functions. Anomaly detection is achieved without the need for machine learning, thanks to effective preprocessing of the velocity evolution. We then analyze two characteristics of detected anomalies: the number of maxima which they cross and the initial and final positions of the particle with respect to two minima in a potential. For determining each characteristic, we employ supervised learning, requiring only one hidden layer with 32 neurons. 1 April 27, 2024 1 Introduction 2
|
|
|
Causativity in Contemporary Portuguese
Laufková, Petra ; Čermák, Petr (advisor) ; Svobodová, Iva (referee) ; Svobodová, Petra (referee)
Univerzita Karlova Filozofická fakulta Ústav románských studií Románské jazyky Abstrakt disertační práce Mgr. et Mgr. Petra Laufková KAUZATIVITA V SOUČASNÉ PORTUGALŠTINĚ Causativity in Contemporary Portuguese Vedoucí práce: prof. PhDr. Petr Čermák, PhD. 2023 Abstract Causation is one of the basic aspects of the way we conceive coherence in the world we live in. Ways of expressing causativity in languages has therefore been at the center of scientific attention for many years. Causative structures involve two events: a causing event expressing that an entity, the causer, acts on another entity, the causee, and causes its change or activity coded as a second event. On the one hand, our work is a structured compilation of theories and data provided by other scientists, bringing to light different causative mechanisms, their formal description, data related to their distribution and mainly their semantic explanation, based on cognitive linguistics. On the other hand, we carry out research to support theoretical assertions with quantified data and find new results. Contemporary Portuguese has a wide range of morphological, lexical and syntactic causative tools. This thesis describes all of them. Nevertheless, we are mainly interested in what distinguishes Portuguese from other languages we know: the fact that...
|
|
|
Welding problems of the „press chamber“ component
Čermák, Petr ; Dohnal, Ivo (referee) ; Kubíček, Jaroslav (advisor)
Petr Čermák: Welding problems of the "press chamber" component The goal of this work is to produce the "press chamber" component of a food industry machine and selection of a suitable arc welding method, a base and a filler material. Practical part of this work includes technological design of a weldment production process considering all the know-how concerning welding technology, heating process of a stainless steel and a weld quality testing. Especial emphasis is put on analyzing of deformations and residual stresses during welding and taking countermeasures to reduce these undesired defects in the "press chamber" weldment made of high alloy austenitic steel. The final output is the "press chamber" component and a welding jig design reducing occurrence of the undesired deformations or residual stresses.
|
|
|
Using program Rosetta to estimate of soil moisture retention curves from experimental size Bohaté Málkovice
Čermák, Petr ; Doležal, Petr (referee) ; Kameníčková, Ivana (advisor)
Hydraulic characteristics are the most important properties of soil, i.e. retention curve of soil moisture and hydraulic conductivity. Hydraulic conductivity of soil characterizes the ability of the soil to conduct water. Retention curve expresses the relationship between moisture and moisture potential of soil. The running of retention curve is influenced by many factors, eg. grain size and mineralogical composition, content of humus, reduce bulk density and structure of soil. Measurement of retention curves takes a lot of time and money in laboratory conditions therefore pedotransfer functions seem to be an alternative solution. The thesis aims to estimate moisture retention curves of soil in a selected area of interest in South Moravia using program Rosetta (Schaap, 2003). Data of granularity (% content of clay, sand and dust), bulk density of soil and hydrolimits field water capacity and wilting point were used as predictors in individual models of program Rosetta. Data of grain were matched by FAO / USDA system. Retention curves of soil moisture were measured on a sand tank and overpressure devices. The measured retention curves were parameterized by RETC program. Estimated retention curves were graphically compared with measured to determine the quality of the estimate. The accuracy of the estimate was assessed by correlation coefficient R of determination coefficient R2 and standard error SMRE. Usability own derivatives pedotransfer functions is hard to say due to the size of the input data file. I would recommend further verification of data at the other localities in south Moravia.
|
|
|
The evaluation of the lifetime period of welded frame for hydraulic press machine RONDOPRESS
Čermák, Petr ; Mrňa, Libor (referee) ; Kubíček, Jaroslav (advisor)
Petr Čermák: Service time assessment of the welded frame for the hydraulics of RONDOPRESS press machine The goal of this thesis is to assess durability of the welded frame for the hydraulics of RONDOPRESS press machine, which is used at the bakery sector in the food industry. The press machine chamber is made of stainless steel, because of food (dough) processing. But the strengthened part of the press machine consists of a carbon steel frame with a hydraulic cylinder. For the life of the RONDOPRESS machine is determining the rigidity and durability of the frame. Therefore it is necessary to carry out a study of carbon steel weldability, choose a suitable welding method and then make an evaluation of welded frame construction used in terms of weld joints in analyzed areas. Practical part consists of the frame computer model design, stress calculations and the service time calculation for required 1,825,000 cycles, choosing the appropriate welding method and avoiding undesired deformations. The final output is an operational frame of the RONDOPRESS press machine that meets the required service time specified by the number of production process cycles.
|
|
|
Digital conversion of analog signals
Čermák, Petr ; Sedláček, Jiří (referee) ; Murina, Milan (advisor)
My work is focused on digital elaboration of the analog signal. In my work the analysis has been carried out in all parts of digit chains processing analog signal. The entranced variable is signal from measuring coil, which is afterwards strengthen and transfer to a sampler. The sample signal is processed by an A/D converter and then sends to a parallel port. On the basis of acquired data the scheme has been constructed for sample processing. The transfer to the parallel port is done (made) in two steps, at first one part of the word is transferred and then the rest of the word follows. Between the converter and sampler is tight relationship and synchronization. Both of them are managed from one central bus.
|
|
|
Digital conversion of analog signals
Čermák, Petr ; Sedláček, Jiří (referee) ; Murina, Milan (advisor)
My work is focused on digital elaboration of the analog signal. In my work the analysis has been carried out in all parts of digit chains processing analog signal. The entranced variable is signal from measuring coil, which is afterwards strengthen and transfer to a sampler. The sample signal is processed by an A/D converter and then sends to a parallel port. On the basis of acquired data the scheme has been constructed for sample processing. The transfer to the parallel port is done (made) in two steps, at first one part of the word is transferred and then the rest of the word follows. Between the converter and sampler is tight relationship and synchronization. Both of them are managed from one central bus.
|
|
|
The effect of soil structure on the hydraulic characteristics of the soil
Čermák, Petr ; Doležal, Petr (referee) ; Kameníčková, Ivana (advisor)
Soil is very important in the hydrological cycle of landscape. The retention and storage ability depends on the quality, type of structure and other properties of the soil. The retention ability of soil is determined by gravitational pores (the coarsest pores), which are drained off after filling the water. The accumulation depends on the capillary pores in which water is bounded by capillary forces. The soil works also as a filter´s environment which cleans naturally the water. This process can be also converse, when various substances are released from soil to water. The state and amount of water between the surface of soil and level of groundwater affect many important processes such as fertility of soil, drain from drainage area, supply of groundwater sources and others. Structure of soil changes fundamentally by cultivation of soil and types of farming crops. Aggregates are mechanical destructed by weather conditions and soil gradually loses its good qualities, fertility is reducing and flood protection is decreasing. This fact can be avoided by right choice of crops and the type of tillage soil.
|
|
|
Gerund in Spanish and its translation counterparts in Czech and Russian
Kavko, Marharyta ; Krinková, Zuzana (advisor) ; Čermák, Petr (referee)
in English: The purpose of this bachelor's thesis was the analysis of the Spanish gerund and its translated analogues in Czech and Russian languages along with a contrastive analysis of the translations. The main goal of the thesis is to discover which translation equivalents were chosen for the Czech and Russian languages, if they have any similarity and what kind of difference in the translation tradition appears. The main sources for the theoretical part were prominent Spanish, Czech and Russian grammatic and linguistic works. As the source of material for the contrastive analysis of the translation from Spanish to Czech was used the parallel Czech-Spanish corpus InterCorp. For the contrastive analysis of the translation from Spanish to Russian was used the method of manual excerpting from the officially published Russian publications. Key words: Gerund, transgressive, translation, Spanish, Czech, Russian, contrastive analysis
|
|
|
The presence of cooperative learning in Spanish classes: observation and analysis of problems
Hanzalová, Marie Anna ; González Lozano, Javier (advisor) ; Čermák, Petr (referee)
The primary objective of the present study was to conduct an analysis of the presence of cooperative learning in Spanish as a foreign language (ELE) classes in the Czech Republic, with a specific focus on identifying the main challenges encountered by secondary school teachers during this process. To accomplish this goal, a mixed-method research approach was employed, utilizing an online questionnaire specifically designed for Spanish teachers. The initial section of the questionnaire encompassed an investigation into the participants' level of familiarity with the term "cooperative learning," as well as their knowledge and utilization of various cooperative techniques. Furthermore, the study explored the specific areas in which cooperative learning was applied, the essential prerequisites for its successful implementation, and the associated benefits linked to this pedagogical methodology. Conversely, the subsequent section of the questionnaire centred around examining the perceived obstacles encountered by teachers, students, and external factors that negatively impact the integration of cooperative learning within the classroom environment. The research findings underscored the widespread awareness regarding the concept of cooperative learning, with each teacher, on average, demonstrating...
|
guest ::
RSS feed.