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Vplyv extrémneho umyvacieho procesu na pevnosť v ohybe lepeného spoja v listnatom dreve
Tuhý, Dušan
The diploma thesis is focused on the issue of the effect of the washing process on the bending strength of the glued joint in a special solid wood panel made of hardwood. The goal was to analyze currently available adhesives and types of joints in solid wood panels and to deal with the issue of the washing process and its influence. The selected glue was PVAc glue Rakoll ® GXL 4 and a butt joint, and then the changes in bending strength were compared on wood samples from beech, oak, ash and maple after thirty cycles of an intensive washing process using cleaning tablets and subsequent acclimatization of the samples. These were compared with samples that did not undergo the cleaning process.
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Stanovení mechanických vlastností dřeva v čerstvém stavu
Jakeš, Ondřej
This bachelor thesis deals with the determination of mechanical properties of wood in a fresh state. The object of the research was Acer platanoides. The mechanical properties were determined using the destructive method on the Zwick Z050. The primary objective was to determine the density, the modulus of elasticity, the modulus of rupture and also to determine the relationship between the individual variables. The secondary objective was to use the results obtained and to compare the density variability along the trunk and the density dependence on the cardinal point.
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Stanovení pružnostních a pevnostních charakteristik dřeva v čerstvém stavu
Bielesz, Robin
This thesis examines the elasticity and strength characteristics of freshly felled timber. Specifically, the wood of Norway maple (Acer platanoides L.). There was a whole trunk of one tree from urbanized environment, which were marked the world sides. After production of individual samples with dimension od 20 × 20 × 30 mm it has been necessary for each sample to describe his former position in the trunk (height, location in the trunk, location of the world side). The final experiment was performed on the testing machine Zwick 050, samples were tested by destructive method by pressure along the fibers. Then the results were processed using program testXpert from Zwick. The result is how to change the density, strength and elasticity characteristics in different locations in tree trunk.
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Výskyt podkorních a dřevokazných druhů hmyzu na javorech (Acer spp.)
Janík, Daniel
This bachelor thesis deals with maple (A. pseudoplatanus, A. campestre a A. platanoides) tree wood attacking pests. The work addresses potential pests of the Acer genus in the form of an extensive scientific literature and other sources review. The findings are that there are not many threatening xylophagous species with calamity potential currently present in the Czech Republic. An experiment with wooden insect traps was introduced in 2019 to confirm this hypothesis in the future and to possibly extend the spectrum of maple-attacking species. The results from the bachelor thesis experiment will be published in own diploma thesis, which will be focused on wood damage itself, pest spreading and their detailed biology.
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Vliv defektů ve dřevě na stanovení rychlosti šíření zvuku ve dřevě v čerstvém stavu
Vobořil, Matěj
This bachelor research deals with determining the speed of sound propagation in wood in fresh state. Specifically, maple milk (Acer platanoides L.) was investigated. Acoustic properties were determined by the non-destructive method thanks device from Fakopp company. These were an ultrasonic timer and a microsecond timer. Sensors like SD02, TD45 and US10 were selected for measurement. The primary objective was to determine the velocity of the sound signal propagating both 1 m long trunk and the 20 x 20 x 300 mm sized samples and to determine the effect of wood defects on that velocity. The secondary objective was to determine the dependence of the measured results depending on the world side.
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Srovnání rychlosti akustického signálu s mechanickými vlastnostmi dřeva javoru
Fišer, Petr
Work is processed by comparing the propagation velocity of the acoustic signal in the maple and hornbeam. Another object of this work was to determine the dependent propagation speed of the acoustic signal in comparison with the mechanical properties of maple wood. Meaurement the speed of the acoustic signal was measured acoustic tomography Fakopp ArborSonic and 3D mechanical properties were measured in a universal testing machine ZWICK Of the 050 samples were used from one maple and hornbeam one that grew in urban environments.
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Jídelní stůl z masivního dřeva
Svojšová, Iveta
The reason why this thesis was crated is that the author was asked to design this table according the needs of investors and also asked to provide the manufacturing process. That lead to the construction design and final production of the table. Author then could be present in the whole realization process. The table was crated with respect for nature, craft and personal approach to the entire implementation.
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Analýza vývoje tržních cen vybraných druhů a jakostních tříd listnatého řeziva
Šoupalová, Jana
This thesis is focused on price development of selected hardwood lumber types and quality grades. Processed analysis provides a comprehensive overview of the price development on the Czech market for the reference period 2008--2012. Selected tree species were oak, beech, maple and alder. All processed data were provided directly to the lumber producer and subsequently were supplemented by the published statistics from the Czech Statistical Office. Provided data were divided into two aggregated classes for each tree species. Aggregated classes were formed according to ways of lumber using, thus accordind to its quality. Prediction for 2013 is created in second part of the thesis using basic techniques of the conjunctural time series analysis. However, because of the existential problems of one of the cooperating companies in 2013 was not possible to accurately verify this prediction.
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