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Electric Drive Diagnostics and Utilization in Agricultural Machinery
Čedík, Jakub ; Pexa, Martin (advisor) ; Kumhála, František (referee)
This doctoral dissertation thesis deals with rotary mowers, specifically with the issue of mulching.
In the theoretical part the reader is being familiar with the technology of mulching and its importance. Further, the individual types of mulchers and its advantages and disadvantages are described. The literary analysis of energy demands of rotary mowers is stated. Further, the parameters influencing energy demands of the mulcher are also analyzed.
The results of measurement of the energy demands of the mulcher with vertical axis of rotation are presented. The dependency of input power, specific energy consumption and fuel consumption on mass performance of the machine are created. Furthermore, the energy demands was determined, while mulcher was working continuously at the permanent grassland. The energy losses of the mulcher were also analyzed.
The effect of modification of operational and constructional parameters on the energy demands and quality of work of the mulcher wit vertical axis of rotation is studied. From the constructional parameters the shape of working tool, especially cloth angle and rake angle of the tool, and shape of the cover of the mulcher workspace is modified. From the operational parameters the cutting speed and mass performance according to conditions is modified.
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Factors affecting the properties of glued joints for glues used in the wood industry
Boška, Pavel ; Böhm, Martin (advisor)
Dissertation focuses on the influence of selected factors on the properties of the bond glued by acetate polyvinyl adhesives. Factors such temperature and moisture content of the environment, the pressing pressure and cyclic stress. Despite the same type of adhesive, the properties may vary for different producers of adhesives and according to which the product is not intended. Influence will be compared to the test samples of dried beech timber with regard to shear bond strength. They will be compared properties of adhesives from different manufacturers and different destination. Test samples and test progress carried out in accordance with current standards, or largely based on. This research should help users streamline the process of adhesive bonding and reduce the production costs of the bond.
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Mophological and molecular diversity of a tropical tree species Guazuma crinita in the Peruvian Amazon
Tuisima Coral, Lady Laura ; Lojka, Bohdan (advisor) ; Helena, Helena (referee)
Fast growing tree species Guazuma crinita (Malvaceae) was selected as a priority species for domestication in the Peruvian Amazon due its important contribution to the livelihood of local farmers. Its domestication process is still in an early age as for many tropical tree species little is known about its genetic variability and we dont know anything about the impact of domestication on its genetic resources. The main objective of this research was to assess the genetic variability of G. crinita within and among populations in the Peruvian Amazon by the use of morphological (wood physical traits) and molecular (ISSR and AFLP) markers.
Wood physical properties among six G. crinita provenances were evaluated. Wood samples were drilled from the base middle and top of the stem of 12 randomly selected eight-years-old trees for determination of wood measurement. Pearson correlations between physical properties were also determined. All wood physical properties except green density differed significantly among provenances. We also found statistically significant variation due to stem level position. The moderately dense wood and the coefficient of anisotropy (1.6) suggested that G. crinita has stable wood; they represent important advantages in terms of costs for transport and transformation process. The results suggested potential to select provenances with desirable wood properties for further breeding and domestication. Due to the variation found even in limited tree samples it is recommended further analysis with more extensive number of samples from different provenances and planting zones.
This research presents the first assessment of genetic variability based on inter-simple sequence repeat (ISSR) markers for 44 G. crinita genotypes from a clonal garden multiplication established in the Peruvian Amazon Research Institute (IIAP) in Ucayali region. Ten ISSR primers amplified a total of 65 bands of which 61 were polymorphic (93.8%). The range of DNA amplification varied from 260 to 2200 bp. Among the provenances overall genetic differentiation (Gst) was 0.03 indicating 97% of genetic diversity within provenances. Gene flow (Nm) was 12.9 alleles per generation. Cluster analysis was not related with geographic origin suggesting a common gene pool which was supported by calculation of weak positive correlation was found between genetic and geographic distance.
With the use of AFLP markers an insight on how domestication process does impact G. crinita genetic resources is also reported on this research work. I was able to generate fingerprint for 58 leaf samples representing eight provenances and three population types, 19 from a natural regenerated population 15 cultivated in home garden nursery and 24 from a collection of genotypes considered as semi-domesticated population. Seven selective AFLP primer combinations were used. A total of 171 fragments were amplified with 99.42% of polymorphism at species level. Each type of population generated fragments with 72.51% 49.12% and 54.39% of polymorphic fragments respectively. Neis genetic diversity and Shannon index information were found to be higher in the population of natural regeneration compared to overall semi-domesticated population (He = 0.10 and 0.9; I = 0.19 and 0.16 respectively). The analysis of molecular variation (AMOVA) showed higher variation within provenances rather than among (84% and 4% respectively). UPGMA clusters analysis and PCoA did not showed correspondence between genetic and geographic distance in addition their correlation was not significant. There was a significant genetic differentiation among types of population suggesting slight genetic bottleneck in semi-domesticated populations yet with relatively high levels of genetic variation.
In situ conservation for populations with high levels of genetic diversity was recommended. In addition proper management of natural regeneration and ex situ genotype collections might be a good conservation strategy to maintain G. crinita genetic resources.
The use of morphological (wood physical traits) and molecular markers were successful to reveal genetic variability of G. crinita and they could be used for other tropical tree species. For further researches it is emphasis to extent the number of samples and geographic scale.
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Assessment of in vitro antioxidant properties of medicinal and edible plant extracts
Tauchen, Jan ; Kokoška, Ladislav (advisor) ; Jaromír , Jaromír (referee)
Identification and characterization of plant-based products with antioxidant and anti-proliferative effects has received much interest over the past few years as possible therapeutic mean for treatment of diseases likely to be associated to oxidative stress (such as atherosclerosis, diabetes, and cancer). This study provides characterization of in vitro antioxidant and/or anti-proliferative potential and phytochemical profile of (i) 39 wine samples of underutilized Georgian grapevine cultivars, (ii) extracts of 22 samples of medicinal plants from Ethiopia and (iii) 23 samples of edible and medicinal plants from Peruvian Amazon. For this purpose, 2,2-diphenyl-1-picrylhydrazyl radical assay (DPPH), oxygen radical absorbance capacity (ORAC) assay, total phenolic content (TPC), and cell viability assay based on metabolization of tetrazolium bromide (MTT) to formazan, together with methods based on high performance liquid chromatography (HPLC-ultra violet/visible spectrometry and HPLC-tandem mass spectrometry) were used. Georgian red wines (particularly Saperavi cultivars) exhibited higher antioxidant capacity (average DPPH and ORAC values at 5.1 and = 10.6 g TE/L wine, respectively) in comparison to Central and West European cultivars [Pinot Noir (DPPH = 3.1 and ORAC = 9.4 g TE/L wine), Cabernet Sauvignon (DPPH = 3.0 and ORAC = 7.3 g TE/L wine) and Cabernet Moravia (DPPH = 2.0 and ORAC = 8.5 g TE/L wine)]. Georgian wines contained significantly greater concentrations of quercetin (between 14.44 and 1.07 ug/mL), kaempferol (between 1.68 and 0.03 ug/mL) and syringic acid (between 12.59 and 4.72 ug/mL), whereas possessed lower quantities of resveratrol (between 5.11 and 0.32 ug/mL) in comparison to Central and West European wines. Amongst edible and medicinal plants from Ethiopia and Peruvian Amazon, only Dodonaea angustifolia (IC50 for DPPH = 22.2 ug/mL, ORAC = 767.6 ug TE/mg extract; IC50 for Hep-G2 = 120.0 ug/mL), Rumex nepalensis (IC50 for DPPH = 5.7 ug/mL, ORAC = 1061.4 ug TE/mg extract; IC50 for Hep-G2 = 50.5 ug/mL), Inga edulis (DPPH and ORAC = 337.0 and 795.7 ug TE/mg extract; IC50 for Hep-G2 and HT-29 = 36.3 and 57.9 ug/mL) and Oenocarpus bataua (DPPH and ORAC = 903.8 and 1024.4 ug TE/mg extract; IC50 for Hep-G2 and HT-29 = 102.6 and 38.8 ug/mL) have demonstrated combinatory antioxidant/anti-proliferative efficacy. Selective anti-proliferative activity was observed for Verbascum sinaiticum (IC50 for Hep-G2 = 80.6 ug/mL) and Annona montana (IC50 for Hep-G2 and HT-29 = 2.7 and 9.0 ug/mL, respectively). Above-mentioned plant material showed only weak or non-toxic effects towards normal cell line. Despite the fact that extracts of Jasminum abyssinicum (IC50 for DPPH = 26.3 ug/mL, ORAC = 1023.7 ug TE/mg extract), Rumex nepalensis (IC50 for DPPH = 5.7 ug/mL, ORAC = 1061.4 ug TE/mg extract), Mauritia flexuosa (DPPH and ORAC = 1062.9 and 645.9 ug TE/mg extract), Myrciaria dubia (DPPH and ORAC = 641.9 and 642.6 ug TE/mg extract) and Theobroma grandiflorum (DPPH and ORAC = 714.8 and 821.9 ug TE/mg extract) have exhibited considerable antioxidant effect, these species were found to possess moderate to low anti-proliferative potential or have shown to be toxic to normal cells line. In all cases it was detected that phenolic compounds content correlated strongly with antioxidant activity, however weakly with anti-proliferative effect. Results suggest above-mentioned species as prospective materials for further development of novel plant-based agents effective against oxidative stress related diseases. However, it is necessary to perform further research which would be focused on detailed characterization of their chemical composition, pharmacological effects and toxicological safety, in order to verify their possible practical use.
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Optimization and application of in vitro techniques in selected members of the family Brassicaceae
Hilgert-Delgado, Alois Antonín ; Fernández Cusimamani, Eloy (advisor) ; Jana, Jana (referee)
This thesis is focused on the application and optimization of biotechnological methods within the family Brassicaceae. Most of this thesis is focused specifically the genus Brassica. The main objective of this dissertation thesis was to optimize and apply selected biotechnological methods in the resynthesis of oilseed rape (B. napus) from its baseline species (B. oleracea, CC and B. rapa, AA) and subsequently create valuable genetic plant materials.
The optimized procedure implemented in my work have exhibited better results of hybrid production (resynthesis) than in similar published experiments and provides a simplified and less laborious method via simple ovule culture and early hybrid verification.
The next accomplished step was to work with a wider range of materials using a broader source of different and contrasting genotypes from Brassica rapa (spring and winter oilseed and vegetable turnips) and B. oleracea (green and purple curly kales and cabbages) for new combinations and wider genetic diversity.
It was concluded that the optimized ovule culture protocol with early verification, developed in the framework of this thesis, is satisfactorily sufficient enough to be applicable in breeding programmes, aimed at diversity expansion of winter oilseed rape gene pool, as the resynthesized embryos were derived in most combinations.
New resynthesized verified lines were colchicine treated in order to obtain diploid regenerants and the fertile plants were self-pollinized and crossed with elite oilseed rape lines for further research and breeding.
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Plasmodiophora brassicae on winter rape
Řičařová, Veronika ; Ryšánek, Pavel (advisor) ; Jaroslav, Jaroslav (referee)
Winter oilseed rape (Brassica napus) is an important crop in the Czech Republic. Clubroot disease caused by the pathogen Plasmodiophora brassicae Wor. is a serious and still-growing problem for oilseed rape growers. Research on P. brassicae in the Czech Republic is therefore important for the development of effective strategies to manage clubroot under Czech environmental conditions.
One of the aims of this study was monitoring of this pathogen. The disease was previously widespread in commercial vegetable production and in hobby gardens. Since 2010, oilseed rape clubroot started to spread across the whole country, whereas it had previously only been observed in the northeast. Clubroot occurrence was monitored for five years by the Union of Oilseed Growers and Processors on the basis of disease symptoms present on oilseed rape fields. The presence of P. brassicae and clubroot symptoms were reported in all regions of the Czech Republic, except the Ústecký Region, and in 31 out of 76 districts. At present, at least 130 fields are known to be infested by the pathogen, but this number is very likely underestimated. Some soil samples were also tested by conventional PCR (polymerase chain reaction) to evaluate the possibility of their usage. All 14 suspected samples tested positive by PCR.
The next aim was to evaluate the pathotype composition of P. brassicae populations from the Czech Republic, according to the three evaluation systems, and to determine soil inoculum loads for representative fields via traditional end-point PCR as well as quantitative PCR analysis. There were considerable differences between the populations of P. brassicae, and the number of pathotypes varied depending on the evaluation system and the threshold used to distinguish susceptible vs. resistant plant reactions. This is the first study comparing the effect of different thresholds. Using an index of disease (ID) of 25 % to distinguish susceptible vs. resistants reactions, there was a total of five pathotypes identified based on the differentials of Williams, five with the system of Somé et al., and 10 with the European Clubroot Differential (ECD) set. However, based on a threshold of 50%, there were five pathotypes according to the evaluation system by Williams, four based on the differentials of Somé et al. and 8 with the ECD set. Changing of the thresholds led to the reclassification of some pathotypes. Pathotypes 7 by Williams was the most frequent in both thresholds. High amounts of pathogen DNA were found in many of the field soils analysed by quantitative PCR.
Experiments with P. brassicae-resistant cultivars of winter oilseed rape were conducted in an infested field and greenhouse. In the greenhouse, six resistant cultivars were grown in infested soil collected from various fields in the Czech Republic and assessed for index of disease (ID %). The best results bring cultivar Mentor (2+- 0.7 %) closely followed by cultivar SY Alister (5+-1.1 %), the highest ID had cultivar CHW 241 (30+-3.8%). In the field experiment, seven resistant cultivars were grown, and disease development was monitored monthly. The lowest index of disease brought cultivar Andromeda (3+- 0.8 %) and PT 235 (4+-1.5 %), the highest ID has cultivar CWH 241(46 +- 6.5 %) in the first season and in the second season any cultivar achieved 25 % ID. Yields were measured at the end of the cropping season. The highest yield was achieved by cultivar SY Alister (6.1 t/ha) in the first season and cultivar PT 242 (5.03 t/ha) in the second season. The inoculum level was measured across the field by (qPCR), and a map of the infestation was created. The highest spore concentration was found on the field entrance. Collectively, the information obtained on the effectiveness of host resistance and pathogenic diversity of P. brassicae populations from the Czech Republic may help to more effectively manage clubroot in this country.
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Analysis of selected factors affecting occurrence of Chalara fraxinea in the environment.
Havrdová, Ludmila ; Šrůtka, Petr (advisor) ; Jaroslava, Jaroslava (referee)
Extensive investigation of ash dieback impact on different rural vegetation types (solitaires, scattered plantations, riparian stands, scree- and ash-alder alluvial forests) was performed in the Lusatian Mts. (the Czech Republic) between 2011 and 2013. The rate of ash dieback and 27 environmental variables were investigated in 80 research plots with a total of 1045 evaluated trees. The developed model (GLM) explained ca 27% of the disease variability. Particular models for each vegetation type importantly differed from each other and explained 28--46% of the disease variability. The variables that positively affected the disease impact included the host crown area, ash area and rate of ash in the stands, tree layer area, canopy closure, north aspect, shrub and herbaceous layer canopy, vertical heterogeneity and standard deviation of TPI. Tree height, the distance and damage of the nearest host as well as the water source distance, slope and its standard deviation affected it negatively. The coincidental attack of the trees by Armillaria sp. and Hylesinus fraxini positively affected the disease progress, whereas the presence of Nectria sp. and Aceria fraxinivorus conclusively decreased progress, most likely via the induction of secondary metabolites. The highly conclusive regression of ash dieback on the number of days with an air humidity of >95% between 6--11 a.m. in the main period of ascospore spread was identified. Because the air humidity near the ground was highly affected by local factors, a GLM model explaining the variability of air humidity with that of investigated factors was developed. This model explained 77% of the variability attributed to air humidity, local factors (TPI and SD of TPI, aspect, slope, altitude, distance from open water, tree and shrub layers canopy, tree stand height, etc.) greatly affected the disease impact related to air humidity. The landscape form was identified as a factor (most likely via air humidity) that affects the impact of the disease -- for example, the stands on mountain tops and slopes were less affected than the stands in valleys. The vegetation types highly differed in the disease extent. In general, the solitaires and scree forests were significantly less damaged than mixed ash-alder forests and riparian stands. The smaller stands were less affected than the more extended, the stands enclosed in canopy of other forests were less damaged than comparable vegetation in open landscapes and stands with higher humidity (riparian stands and mixed ash-alder forests) were more damaged than those without water. The outcome clearly supports the possibility of development and usefulness of appropriate forest and landscape management of the disease.
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Evaluation of information security in information systems
Urbanec, Jiří ; Toman, Prokop (advisor) ; Vlasta , Vlasta (referee)
Information is a valuable asset for organizations and a source of competitive advantage nowadays. Therefore it is necessary to retain information security characteristics of processes and systems in required limits and continuously evaluate the state using measurement. The problem in measurement shows to be in the selection of suitable characteristics and measures of the processes or the products, which are subject to measurement.The main aim of the dissertation thesis is to design methodic for evaluating information security in information systems and formulate conclusions and recommendations for its use in practice. The situation in The Czech Republic was obtained based on a quantitative survey in which data was collected by means of a questionnaire survey (N=785; n=101) and qualitative research was conducted in the 3 organizations from financial sector in the Czech Republic. Results showed that at present an absolute majority of surveyed organizations evaluate information systems from the perspective of risk to valuable information (58.49%). Organizations evaluating information security are most often to identify weaknesses and emerging issues (41.5%). Only a 17.6% of them measure. The designed methodic identifies behavioral model of the organization, defines measurable characteristics of the system and the organization based on extended security model, defines process of development of the measures based on GQM tool, engages measurement process compatible with ISO 27004 and presents evaluation procedure using measured values. The proposed procedures and constructs focused on improvement of field detected by the survey, the "information classification" and "difference between perception of information value between owner and processor". The procedures were validated on two anonymous organizations and are presented in form of case studies. One of the conclusions is, that proposed methodic is applicable mostly in organizations with strong technical and financial base, where it is possible to overcome requirements of measures development processes and measurement application. Also the methodic of evaluation has its own limits of applicability.
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Socially Excluded Localities and Their Revitalization. Case Study: Ústecký Region.
Zoubková, Věra Thea ; Maier, Karel (advisor) ; Jakub, Jakub (referee)
The dissertation deals with the incidence and revitalization of socially excluded localities in a defined study area. The aim of this contribution is to identify and visualize the situation of the Ústecký Region in order to find common patterns of urban deprivation occurrence and to establish the guiding principles of revitalization policies in the Czech Republic. The research took place from September 2010 to June 2015. It combined qualitative and quantitative methods, in-situ and desk research. An analysis of primary and secondary data revealed 130 excluded localities in 42 towns and cities out of 354 in the region. The majority of deprived localities (87 %) can be found in highly urbanized areas. Two thirds of localities are small areas with up to 100 inhabitants. Socially excluded areas emerge in the centre, residential districts as well as on the outskirts of towns; however, three fifths of localities are not spatially segregated. Prefabricated housing estates are the largest and most populated deprived areas. Every other inhabitant of socially excluded localities in the Region lives in a prefabricated house. Brick houses are the most proliferated type of housing facility used as accommodation for socially excluded people. They can be found in every other deprived area. Vast majority of them was built before 1989. Family houses are deprived very scarcely; however, they belong to the most dilapidated part of socially excluded housing estate. Two thirds of localities have developed naturally, while the other third has been created by a regulated relocation of socially excluded people. Vast majority of deprived areas have existed for more than 5 years. Private property prevails. Half of the localities have entered the process of revitalization to improve the urban environment, human resources and security. Applied policies aim to keep the inhabitants in place and improve the quality of public space and service. However, involvement of residents in local regeneration policymaking is weak and ineffective. The renewal process depends on grants and subsidies. Europeanization is strong especially in big cities; nevertheless, most localities are small and therefore don't qualify for the sources of the built environment programs which prefer large areas of intervention. Results of revitalization process differ from one locality to another. Areas of housing and employment fall behind in particular. As far as property regeneration is concerned, the best owners are municipalities, house unit owners associations and housing associations. Not in one case, however, reaches the share of regenerated housing units 50 % of deprived properties. In any case, the market prices of local flats stay low compared with those of correspondingly equipped properties elsewhere in town.
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Mathematical modelling in basin of Litavka in the framework integrated system water
Hejduk, Tomáš ; Pech, Pavel (advisor) ; Máca, Petr (referee)
These thesis brings new findings in flood issues, which importance has been sharply increasing in the light of last years experience. Hypotheses about the usefulness of hydrological measurements in the creation of computational geometry watercourses, as well as using the data from aerial laser scanning in the preparation of computer tracks water flows have been confirmed. Presented papers introduce the use of new technologies, knowledge and other results of applied research in the field of preparation of input data for hydrodynamic models, geographic information systems, personal identification and early warning and information sharing to support the elimination of consequences of natural disasters or traffic accidents. The above presented findings about the use of airborne laser scanning data and synthesis these data with hydrological measurements are of great importance for the improvement of flood prevention. Another practical use of these findings lies in urbanism planning and flood forecasts. The effort is to increase the security of citizens in the case of threats to their security through early warning - ie. Preventative protection by results of conducted research in the field of mathematical modelling rainfall-runoff and passage of flood flows in the river system providing new knowledge for the identification and registration of persons. During the research conducted, the attention was paid to define tools supporting integrated activities of the state security and rescue forces, including increased education and communication between state administration, local governments and the public. However the main goal of this work is to prevent the effects of natural and anthropogenic risks to human health and property of citizens. The attention is paid especially on the most common natural hazard represented by the floods.
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