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Reaction of certified seed and farming seed in selected variety potato
VANĚK, Petr
The main aim of this bachelor work was influence of certified seed and farmer seed in selected potato varieties. In 2008 attempts were established with certified seed and farmer seed. The selected varieties were evaluated by the number released plants, production of potatoes, proportion of market tubers and starch kontent in tubers. Comparisons were 4 varieties with different lenit of growing season {--} Magda, Adéla, Ditta, Bionta.
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New test approach and evaluation of dynamic and thermal parameters of elastomers
Pešek, Luděk ; Vaněk, František ; Procházka, Pavel ; Bula, Vítězslav ; Cibulka, Jan ; Vaněk, Petr
The new test approaches for evaluation of thermo-visco-elastic parameters of elastomers are designed, realized and discussed herein. The main attention is devoted to a kinematic excited rubber beam sample under transient resonant sweep excitation. Mechanical material characteristics, i.e. Young modulus and loss angle, are identified from analytical formulas of FRF function based on measured dynamic loading and response signals. Heat material constants were estimated indirectly by numerical thermo-mechanical FE model and matching numerical and experimental results. The „sweep” regime tests serve for estimation of thermal and mechanical dependences. Long-term tests with cyclic resonant loading enable analysis of material degradation, such as hardening and permanent deformation, due to fatigue. For dynamic tests with pressure pulsation and sudden loading and unloading the high-power electromagnetic pulsater has been developed for damping rubber segments of tram wheels.
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Kinematic system for measurement of dynamic parametes of vibrationg parts under rotation
Pešek, Luděk ; Vaněk, František ; Procházka, Pavel ; Vaněk, Petr ; Cibulka, Jan ; Bula, Vítězslav
Kinematic system for measurement of dynamic parameters of vibrating parts under rotation.In the contribution the research on the improvement of the kinematic measuring system for evaluation of natural and forced vibration of machinery parts under rotation is presented. The improvement was aimed at the sensor part for a continuous movement of rotating and vibrating disk. For this reason the numerical FE model of the physical model of bladed disk was developed and analyzed. Laboratory verification of the new proposed sensor system was performed under an electromagnetic harmonic excitation. By means of strain-gauge measurement that were placed on several disk blades with a slip-ring signal transmission, the dynamics of the rotor was analyzed and the kinematic system was calibrated.
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The vibrodiagnostic system VDS-UT2 for the investigation of a tram wheel operational vibration and deformation
Pešek, Luděk ; Vaněk, František ; Balda, Miroslav ; Procházka, Pavel ; Vaněk, Petr ; Cibulka, Jan ; Bula, Vítězslav
The system consists of both measuring, acquisition and processing tools for monitoring of tram wheel and wheel set operational parameters,e.g.static and dynamic deformation, displacement, velocity, acceleration and temperature. The measuring on the rotating wheel is realized both by telemetric and by time difference system. Measured data can be remote observed via internet connection with the control PC. Tha acquisition system by Starmans s.r.o provides continuous analog and digital data collection. The control PC processes digital logical signals and evaluates time intervals representing circumferential turning angles between disk and rim. In the contribution the diagnostic system is described and the measured data with damage analysis are presented.
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