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Measurement system for determination of the piezoelectric charge coefficient
Kašpárek, Ondřej ; Skalský, Michal (referee) ; Fialka, Jiří (advisor)
The master's thesis deals with methods of measuring material coefficients of piezoelectric materials with a focus on direct methods of measuring piezoelectric charge constant. The first chapters of this paper focus on the theory of the piezoelectric effect, the description of piezoelectric material coefficients, and the theory of direct measurements of piezoelectric charge constant, where is the generated charge, which corresponds to the mechanical load, measured. The next part of this thesis deals with designing and creating advanced measuring systems based on the quasi-static method, which are measuring the electrical response of the material to a step-change in force or a harmonic force signal straining the testing sample. In the last part, the influences on the measurement results, such as the use of electromagnetic shielding, are investigated using the created measurement systems.
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Measurement of energy harvesters
Kašpárek, Ondřej ; Pikula, Stanislav (referee) ; Kunz, Jan (advisor)
Over recent years the power outputs of piezoelectric energy harvesters have increased to the point where they rival other types of energy harvesting and therefore their sufficient parameterization is necessary. Four piezoelectric PVDF films - DT1-028KL, DT1-052K, DT2-028K a LDT2-028K made by SENZOR SOLUTIONS TE Connectivity were parametrized by two created systems of measurement with force strain. Power outputs of these films when pressed with harmonic force signal with 3 Nrms amplitude are in nW and transferred energies after force impulse with size 300 N are between hundreds and tenths of fJ. Furthermore, values of quality factor, resonance frequency, optimal load resistance and maximal power stability were determined.
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Measurement System for Determining Piezoelectric Charge Coefficient
Kašpárek, O. ; Fialka, J.
The paper focuses on a system of direct measurement of piezoelectric charge coefficient. The created system is based on quasistatic method when harmonic force signal is applied to the examined piezoelectric material. A program in the programming environment LabVIEW was created for control, measurement, and processing. Thanks to the universality of this system from the perspective of hardware, this system offers higher levels of modularity than d33 meters available on the market.
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Measurement system for determination of the piezoelectric charge coefficient
Kašpárek, Ondřej ; Skalský, Michal (referee) ; Fialka, Jiří (advisor)
The master's thesis deals with methods of measuring material coefficients of piezoelectric materials with a focus on direct methods of measuring piezoelectric charge constant. The first chapters of this paper focus on the theory of the piezoelectric effect, the description of piezoelectric material coefficients, and the theory of direct measurements of piezoelectric charge constant, where is the generated charge, which corresponds to the mechanical load, measured. The next part of this thesis deals with designing and creating advanced measuring systems based on the quasi-static method, which are measuring the electrical response of the material to a step-change in force or a harmonic force signal straining the testing sample. In the last part, the influences on the measurement results, such as the use of electromagnetic shielding, are investigated using the created measurement systems.
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Measurement Of Energy Harvesters
Kašpárek, Ondřej
This paper deals with energy harvesting based on piezoelectric principle and options of determining power parameters of piezoelectric energy harvesters. Purpose of the work is to depict one of possible methods in determining these parameters. Subsequently a system for measuring the generated voltage from piezoelectric energy harvesters under harmonic force signal in circuit with external load and a program for evaluating the measured data are put into operation.
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Measurement of energy harvesters
Kašpárek, Ondřej ; Pikula, Stanislav (referee) ; Kunz, Jan (advisor)
Over recent years the power outputs of piezoelectric energy harvesters have increased to the point where they rival other types of energy harvesting and therefore their sufficient parameterization is necessary. Four piezoelectric PVDF films - DT1-028KL, DT1-052K, DT2-028K a LDT2-028K made by SENZOR SOLUTIONS TE Connectivity were parametrized by two created systems of measurement with force strain. Power outputs of these films when pressed with harmonic force signal with 3 Nrms amplitude are in nW and transferred energies after force impulse with size 300 N are between hundreds and tenths of fJ. Furthermore, values of quality factor, resonance frequency, optimal load resistance and maximal power stability were determined.
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Applying project management principles on organization of the national holiday celebrations
Bílková, Lucie ; Hrůzová, Helena (advisor) ; Kašpárek, Ondřej (referee)
This thesis analyzes the causes of organizational problems arising during the preparation of national holiday celebrations. The theoretical part describes the cultural and non-profit sector, deals with the specific management issues of NGOs which organize cultural events, and explains the basic methods and principles of project management. The methodological part lays out the methods used for data collection and analysis. The practical part describes the celebrations of the Struggle for Freedom and Democracy Day on Národní Třída street in Prague, which are organized as a project. Data was collected using observation and interviews with team members and analyzed to discern specific issues facing the project team during the preparation process, and recommendations are provided to address these issues using project management methods.
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New model of cultural center
Kašpárek, Ondřej ; Hucková, Barbara (advisor) ; Melenová, Kateřina (referee)
Culture and Art have, without a doubt, always been major development factors for people and the society as a whole. However, there is no effortless access for everyone or everywhere. This Thesis is focused on the phenomenon of the multifunctional cultural center as an institution developing and initiating cultural and communal life in a region or in a smaller regional city with no cultural infrastructure or background. The first part deals with the discursus of the contemporary cultural centers. Apart from the management issues of the centers, this Thesis handles their work with their target groups as well as their today's mission and activities, which all make these institutions unique. The short summary of the Czech culture centers typology is included; it maps their basic forms in the Czech Republic. The Thesis is ended with a factual proposal of a new multifunctional culture center, which puts the cultural awakening of the citizenry to a more creative way of life with a sense of belonging as its main priority.
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