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Integration in higher-order finite element method in 3D
Kůs, Pavel
Integration of higher-order basis functions is an important issue, that is not as straightforward as it may seem. In traditional low-order FEM codes, the bulk of computational time is a solution of resulting system of linear equations. In the case of higher-order elements the situation is different. Especially in three dimensions the time of integration may represent significant part of the computation.
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Řízení lidí v multikulturním prostředí
Moryc, Katarzyna Małgorzata ; Dvořáková, Zuzana (advisor) ; Vávra, Radovan (referee)
The main objective of the thesis was to define and analyze key aspects of managerial work in multicultural environment, in one of the Shared Services Center department, of multinational company based in Prague, Czech Republic. Further thesis aimed to define essential competencies of the successful manager and leader driving performance of multicultural department and provides recommendations to improve managerial performance in key aspects of manager s work such as communication, motivation, performance management and cross-cultural leadership. It is argued that presence of intercultural interactions between managers and their subordinates, impacts effectiveness of the managerial performance. Thesis consists of theoretical and practical part. First part of the thesis explores theoretical concepts regarding culture, communication, motivation and leadership with respect to multicultural environment specifics. In the second part, used research methods, conducted research analysis and outcomes are presented. Further in practical part recommendation towards analyzed aspects of managerial work that would lead to higher overall department performance are defined.
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Aspects of the virtualization of higher education and its comparison in the CZ and US
Dlauhá, Dominika ; Šedivá, Zuzana (advisor) ; Pour, Jan (referee)
The topic of this thesis is the evolution of online higher education in the CZ and US, from its beginnings to its current state. Emphasis is placed on describing MOOCs and virtualization in education, ranging from technological, pedagogical and didactic aspects to legislature and finance. A survey was conducted to determine the interest in online courses at the University of Economics, Prague and experience with online learning, resulting in an outline of the future development in this area.
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Effect of snowpack on runoff generation during rain on snow event.
Juras, Roman ; Máca, Petr (advisor) ; Ladislav , Ladislav (referee)
During a winter season, when snow covers the watershed, the frequency of rain-on-snow (ROS) events is still raising. ROS can cause severe natural hazards like floods or wet avalanches. Prediction of ROS effects is linked to better understanding of snowpack runoff dynamics and its composition. Deploying rainfall simulation together with hydrological tracers was tested as a convenient tool for this purpose. Overall 18 sprinkling experiments were conducted on snow featuring different initial conditions in mountainous regions over middle and western Europe.
Dye tracer brilliant blue (FCF) was used for flow regime determination, because it enables to visualise preferential paths and layers interface. Snowpack runoff composition was assessed by hydrograph separation method, which provided appropriate results with acceptable uncertainty. It was not possible to use concurrently these two techniques because of technical reasons, however it would extend our gained knowledge. Snowmelt water amount in the snowpack runoff was estimated by energy balance (EB) equation, which is very efficient but quality inputs demanding. This was also the reason, why EB was deployed within only single experiment.
Timing of snowpack runoff onset decrease mainly with the rain intensity. Initial snowpack properties like bulk density or wetness are less important for time of runoff generation compared to the rain intensity. On the other het when same rain intensity was applied, non-ripe snowpack featuring less bulk density created runoff faster than the ripe snowpack featuring higher bulk density. Snowpack runoff magnitude mainly depends on the snowpack initial saturation. Ripe snowpack with higher saturation enabled to generate higher cumulative runoff where contributed by max 50 %. In contrary, rainwater travelled through the non-ripe snowpack relatively fast and contributed runoff by approx. 80 %.
Runoff prediction was tested by deploying Richards equation included in SNOWPACK model. The model was modified using a dual-domain approach to better simulate snowpack runoff under preferential flow conditions. Presented approach demonstrated an improvement in all simulated aspects compared to the more traditional method when only matrix flow is considered.
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Arctic tundra dendrochronology
Lehejček, Jiří ; Svoboda, Miroslav (advisor) ; Monika, Monika (referee)
Historically unprecedented environmental change in the Arctic ecosystems is often given into the context of its past and possible future development. In the region where instrumental meteorological observations are scarce archives need to be investigated in order to address this issues. The comprehensive synthesis one of the archives: long-live circumpolar evergreen Juniperus communis L. shrub is presented here. 20 individuals from southwest Greenland were investigated at the cell anatomy level to understand the ecology of the species and unhide its potential for environmental and climate reconstructions. The findings are as follows:
i) Stop of exponential cross-sectional conduit-lumen widening with increasing age is in contrast with conduit-lumen nature of trees. This indicates that shrubs do not need to saturate their water and nutrient demands via traits of classical hydraulic conductivity law but rather developed different mechanisms. Extreme weather conditions result in prostrate growth form. However, different weather factors probably influence shrub growth differently: While snow and wind act mechanically (a), temperature influences the form of growth physiologically (b). a) So long as the young shrub stem has high resilience to bend back to an upright position after snow melt and so long as it can withstand the wind during the vegetation season it most likely grows upright and the conduit-lumens widen. b) Temperature, resp. freeze-thaw events are responsible for the shrubs preference of safety (finite size of conduit-lumens) over hydraulic efficiency, thus not allowing for more primary growth. All of these (and other) factors are apparently working together and the transition of vertical to more horizontal growth is gradual. As a consequence, the conduit-lumen sizes may not have to be further increased (due to ecophysiological restrictions possibly also must not) because water is no longer transported against gravity.
ii) Observed age/growth trend has to be taken into consideration for further employment of the wood anatomical parameter in paleoenvironmental studies. That is, shrub cell parameters can only be used for this purposes if correctly detrended. This allows for more accurate as well as longer reconstructions because youth trend was often neglected in reconstructions based on shrub annual-rings.
iii) The south-western Greenland Ice-Sheet (GrIS) melt rates reconstruction is presented for the whole 20th century. This part of GrIS is considered as the most active. According to the presented reconstruction current GrIS melt rates are not uncommon for the last century being comparable to first decades of 20th century. This finding is particularly important contribution to the debate on Atlantic meridional overturning circulation (AMOC). Too high fresh water inputs into the Northern Atlantic from GrIS melting may slow down or even stop the AMOC which would result in more continental climate in Europe. Presented results indicate that this threshold lies higher than observed current melt rates of GrIS.
Fascinating Juniperus comunnis species has shown to be able to address many ecological as well as environmental open questions and due to its longevity and abundant distribution has a great potential to become an important player in the Arctic research.
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Iniciace pohybu byčíku, signalizace a regulace pohyblivosti spermií ryb: fyzikální a biochemické řízení
PROKOPCHUK, Galina
The current study attempted to shed light on the regulatory processes and response arrangements of fish spermatozoa during the course of maturation and motility initiation. The first intent of this study was to improve the understanding of the mechanism underlying the acquisition of potential for sperm motility in sturgeon. Up to present work, the physiological process underlying sperm maturation in this species has not been described at all. Our results showed that sperm maturation in sturgeon occurs outside the testes because of dilution of sperm by urine and involves the participation of high molecular weight substances as well as calcium ions present in seminal fluid and/or urine. The second aim of the present study was to investigate the coping mechanisms in fish spermatozoa with osmotic and ionic activating mode, as well as in spermatozoa of euryhaline fishes, to various environmental conditions. We showed that alteration of environmental osmolality might affect the fish sperm in different ways, depending on fish species and modes of spermatozoa motility activation either osmotic or ionic mode. In response to osmotic stress caused by hypotonicity, carp spermatozoa regulated the flow of water across their cell membrane and increased their cytoplasmic volume during their short motility period. In contrast, no indications of sperm volume changes were observed neither in sterlet nor in brook trout spermatozoa, both of which having an ionic mode of motility activation. We also examined the mechanism by which sperm motility triggering in euryhaline fishes can adapt to a broad range of environmental salinity. Our results demonstrated that spermatozoa of euryhaline tilapia, Sarotherodon melanotheron heudelotii, reared in fresh-, sea- or hypersaline water can be activated in hypotonic, isotonic or hypertonic conditions of swimming milieu, provided Ca2+ ions are present at various levels. It was established that the higher the fish rearing salinity or the more hypertonic ambient media at spermatozoa activation, the higher extracellular concentration of Ca2+ ions is required. The results obtained in the present study allow suggesting that osmolality is not the main factor inhibiting sperm motility inside the testis in the S. melanotheron heudelotii. A third aim of this study was investigation of the regulation of motility initiation process and description of flagellar beating initiation in chondrostean spermatozoa. We detected that K+ inhibition of sperm motility in sturgeon can be by-passed due to the pre-exposure of sperm cells to a high osmolality shock prior to its transfer to K+-rich swimming media. Thus, we hypothesized that sturgeon spermatozoa may be activated by use of an unexpected signaling pathway, independent from regular ionic stimulation. The successive activation steps in sturgeon spermatozoa were investigated by high-speed video microscopy, using specific experimental situation, where sperm motility initiation was delayed in time up to several seconds. At motility initiation, the first couple of bends formed at the basal region begins to propagate towards the flagellar tip, but gradually fades when reaching the mid-flagellum. This behavior repeats several times until a stage where the amplitudes of bends gradually reach similar value, what eventually leads to sperm progressive displacement. The total period needed for the flagellum to switch from immobility with rigid shape to full activity with regular propagating bends ranges from 0.4 to 1.2 seconds. In conclusion, the results of the current study bring valuable pieces of information into the general understanding of the processes of maturation of fish spermatozoa, their adaptability to different physical and biochemical circumstances, the extra- and intra-cellular signaling as well as the regulatory mechanisms of motility activation in fish spermatozoa.
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The use of (nano)oxides for metal and metalloid stabilization in contaminated soils
Michálková, Zuzana ; Komárek, Michael (advisor) ; Luke, Luke (referee)
The main objective of the thesis was to evaluate the potential of selected Mn and Fe (nano)oxides for the stabilization of metals and metalloids in contaminated soils. The research was focused basically on three materials - commercial nanomaghemite (Fe III), nanomagnetite (Fe II,III) and a synthetic amorphous Mn oxide (AMO). The main aim of the work was to provide a complex view on the chosen stabilizing amendments regarding not just their direct influence on contaminants mobility and stabilization mechanisms, but also their stability and alterations in soil conditions together with influence on soil microorganisms and higher plants. Firstly, adsorption properties of the tested materials towards Cd, Cu, Pb and As were investigated. In this context, the most effective material showed to be the AMO reaching one to two orders of magnitude higher adsorption capacities than Fe III and Fe II,III under given experimental conditions. Interestingly, the rate of As(V) adsorption onto AMO was increasing with increasing pH as a result of high pHzpc of the AMO (8.1) and significant dissolution of this phase at lower pH values. As a next step, the influence of (nano)oxides on metal(loid)s mobility and other physico-chemical soil characteristics after application to contaminated soil was examined. Again, the AMO proved to be the most efficient in reducing mobile pools of Cd, Cu, Pb, Zn and As. On the other hand, Fe III and Fe II,III addition had generally less significant effects on contaminants mobility. AMO application further resulted in an increase of soil pH connected with AMO dissolution and unwanted decomposition of soil organic matter. When (nano)oxides alterations in soil conditions were observed, MnCO3 coatings were identified on AMO surface while no significant changes were recorded for Fe III and Fe II,III. As the MnCO3 formation was connected with increased AMO stability, AMO particles synthetically covered with MnCO3 coating (denoted as SM AMO) were prepared. Although the SM-AMO had a lower mass loss in soil than pure AMO, the stabilizing efficiency was almost the same for both materials. The differences in surface composition of both materials were decreasing with time as MnCO3 naturally precipitated on the AMO surface in soils while the SM AMO coating was gradually dissolving. When investigating the effect on soil microbiota, AMO efficiently promoted soil microbial activity while no significant changes were observed in the case of Fe III and Fe II,III. The AMO was also able to reduce the uptake of Cd, Pb and Zn by sunflower (Helianthus annuus L.), eliminate Zn phytotoxicity symptoms and increase biomass yield. On the other hand, toxic levels of Mn released from the AMO in an acidic soil were found in sunflower tissues. AMO application is thus recommended for contaminated neutral or slightly alkaline pH with a higher cation exchange capacity in order to avoid unwanted release of Mn. Finally, various types of AMO-biochar composite sorbents were recently prepared and field experiment focused on stabilization of Cd, Pb, Zn and As using studied materials is currently under preparation. The combined results from the thesis highlight the importance of a complex experimental approach dealing with all parts of the contaminated soil environment in order to obtain complete information about the efficiency and usefulness of any newly developed stabilizing amendment.
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Performance recording in Charolais beef herd
Jelínek, Petr ; Toušová, Renata (advisor) ; Petr, Petr (referee)
Summary
In this thesis I dealt with verification of performance of beef cattle Charolais Breed on farm: Chov Charolais spol. s r. o. Slabce. The main objective of my diploma work was to assess the growth abilities of calves Charolais breed from birth till weaning in relation to various factors, for instance: gender, order of calving, number of born calves during one calving, month and year of the birth on the respective farm. The relevant data was assessed for the period of years 2012 - 2015. In this period there was born 324 calves of which 162 bulls, 153 heifers and 9 still born calves. The assessment of calf's growth characteristics was related to the average birthweight, average gain from birth to 120 days, and average weight at the age of 120 and 210 days. For the evaluation of calf's growth characteristics was used data gained from the database of performance testing of beef cattle (KUMP) for the given period. Growth parameters related to selected factors were processed with the use of statistical software SAS 9.3 (SAS 9.3, 2011).
The average weight of young bulls at birth was 33,58 kg and average weight of heifers was 32,99 kg. The average weight of bulls at the age of 120 days was 183,66 kg and the average weight of heifers was 175,58 kg which was demonstrated to be statistically significant (P < 0,01). The average weight of bulls at the age of 210 days was 288,28 kg which is again higher than heifers with average weight of 264,21 kg (P < 0,05). To summarize, there was identified statistically significant difference of the gender influence in behalf of bulls.
After comparison of average weight at birth, at the age of 120 and 210 days separately for twins and an only child, there is obvious and also statistically significant finding (P < 0,01) that the observed twins are usually smaller at birth and their growth abilities are worse than that of only child. The average weight at birth for an only child is about 4,48 kg higher compared to twins. Then the average weight at the age of 120 days for an only child is about 38,68 kg higher than average weight of twings. Finally the average weight at the age of 210 days is about 58,26 kg higher for an only child.
Regarding to the influence of order of calving there was identified no significant effect to both average birth weight and weight at the age of 210 days. The only statistical significance was identified between order of calving and the average weight at the age of 120 days in 1st, 2nd, 5th, 7th, 10th order of calving (P < 0,05). Further I found out that calves in the 1st order of calving have significantly lower average weight from the 1st calving mothers at the age of 120 days than the calves in the 2nd, 5th, 7th, 10th order of calving. The average weight of calves at the age of 120 days is about 9,29 kg lower than weight of calves in the 2nd order of calving. On the other hand the average weight of calves at the age of 120 days in the 5th order of calving is about 18,37 kg higher than weight of calves in the 1st order of calving. Similarly, calves in the 7th order of calving have about 13,63 kg higher weight than calves from the 1st calving mothers. And also calves at the age of 120 days in the 10th order of calving have about 15,78 kg higher weight than calves from the 1st calving mothers.
In respect of influence of year of birth was identified statistically significant different level (P < 0,01) of the average birthweight in year 2013 compared to other years. Similarly there was demonstrated the statistically significant difference (P < 0,01) regarding to the average gain from birth in year 2013 compared to other years. The average birthweight in 2013 was 34,91 kg. The lowest average birthweight of 31,65 kg was observed in 2015. And for instance in 2012 the average birthweight was 32,48 kg which is still about 2,43 kg lower than in 2013. Regarding the evaluation of the average gain from birth till the age of 120 days there was only reported value of 1046,78 g in 2013. The best year regarding the average gain from birth till the age of 120 days was year 2014 which represented value of 1214,37 g.
In the observed breed there took place births predominantly from January till June. Regarding the month of birth there was demonstrated statistically significant difference (P < 0,05) in respect of average birthweight of calves born in May 31,98 kg compared calves born in February 32,55 kg and in March 33,07 kg. Further was identified statistically significant difference regarding the average gain from birth for calves born in June 995,28 g compared to calves born in February 1197,87 g (P < 0,01). Similarly in March was reported value of 1181,18 g (P < 0,05). The last statistically significant difference (P < 0,01) was identified in respect of average weight at the age of 210 days of calves born in May 199,55 kg and in June 201 kg in comparison to calves born in January 282,05 kg, in February 284,65 kg, in March 277,21 kg and in April 277,76 kg. To conclude, based on the statistical analysis, conclusive results and literary sources there had been confirmed hypothesis that internal factors positively affect the growth abilities of calves.
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Orangutans breeding and factors affecting their reproduction in captivity and in the wild
Kalkušová, Olga ; Kubík, Štěpán (advisor) ; Burešová, Eva (referee)
Information concerning orangutans living in the wild and the issue of their breeding has been summarized within the framework of this thesis. Orangutans in their natural habitats in tropical rainforests of Sumatra and Borneo are not subjected to the same influences as those bred in captivity. Their reproduction thus differs in certain aspects. Reproduction of orangutans in the wild is strongly influenced by their solitary way of life. Females are accompanied only by their young or eventually by other females and according to the studies they seek contact with males only in their period of rut. The contact is then limited to a period of time needed for copulation. One exception to this behaviour may be couples with juvenile males. After birth, the female looks after the young male for up to 8 years, having no rut during this period. The cycle of females living in the wild also shows dependency on the availability of food supply. Negative energy balance during which the cycle stops has been observed during periods of food scarcity. In the following period with abundance of food, the cycle is renewed again. The cycle renewal also occurs in cases when the female loses her young. As a consequence of these reproductive limitations females may give birth to 4 young at maximum in their life.
Guidelines have been drawn up for breeding in zoos which regulate the conditions and suitability of the exhibits so that they meet the orangutans needs. Their natural mental and physical activity is related to their health and natural behaviour. However, despite all efforts the zoos cannot provide the same conditions to the orangutans as those they would have in the wild. The forced increased socialization and contact with other individuals held in captivity may bring stress, stereotype behaviour and associated health problems which are rather frequent with orangutans bred in captivity.
According to the records in the pedigree books, the age of first reproduction and the interval between births were shorter in case of females kept in captivity. Even the keeping of males and females in one exhibit increases the probability of copulation and becoming pregnant. These changes also entail certain risks according to the studies. Breeding in captivity embodies higher mortality rate of young and adult animals. This is probably caused by young age of females at the birth and short intervals between births which are often shorter than 4 years. Females born in captivity also lack experience which they gain in the wild by learning and observing and are not able to take care of their young or refuse it later. Even females that got pregnant between the age of 11 and 14 have been described. However, such pregnancy poses a great risk for females and they die soon after birth or live much shorter. Young orangutans born in captivity were often taken away from their mothers. It is not very suitable on the one side, but on the other side, after having their young taken away from them, the females started a new, full-fledged cycle in a few weeks and could become pregnant again. However, as direct care of the young by humans has a negative effect, the young are often given back to their mothers which is successful in many cases.
Orangutans have been studied for more than 40 years and a lot of things concerning their breeding in captivity have changed during this time. Zoological gardens are trying to provide the orangutans as natural conditions as possible. It is necessary for the exhibits and the enrichment to provide enough physical and mental activities to the orangutans. Despite these efforts, the limited space and the related contacts between individuals may bring stressful situations. These are then manifested in the behaviour and health of the orangutans.
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Comparison of the performance of selected varieties of winter oilseed rape (Brassica napus)
Krouželová, Jana ; Bečka, David (advisor) ; Roman, Roman (referee)
Winter oilseed rape is the most important oilseed plant grown in the Czech Republic. During
recent years, rapeseed sown areas rapidly increased due to its complex usage in industry.
Similarly, the rapeseed oil gains importance which is used in food industry.
The successful cultivation of rapeseed includes the right cultivation technology as well as the
choice of suitable variety which will be the adapted to climatic conditions of location. There
are over 600 varieties to choose from based on Common Catalogue of Varieties of
Agricultural Plant Species from which is about 80 varieties commonly used in practice in
climatic conditions of the Czech Republic. Suitability of these varieties and their yield are
tested based on variety testing conducted by ÚKZUZ. The varieties which proved to be
suitable based on previous testing are recommended for cultivation and placed in
Recommended List of Varieties which helps farmers to orientate in new varieties in the Czech
Republic.The aim of this diploma thesis is a comparison of the performance of selected varieties of
rapeseed which were cultivated in semi-operational conditions in Humburky,
Kralovehradecky region. In this theses yield, oil content, 1000 seed weight were compared.
Two hypotheses were set:
1) Hybrid varieties reach higher height and yield
2) Oil content of liner and hybrids cultivars is equivalent
Further these features were observed: plant height, pod number on the terminal raceme, stalk
number on the terminal raceme, number of primary and secondary branches, height and length
of yield floor and their correlation with yield.
Cultivar Faktor KWS (hybrid) reached the best yield from selected varieties, yielding 5,02 t/
ha (119,2 % average yield). The average yields of liner and hybrids cultivars were almost
equivalent (4,16 t/ha hybrids and 4,10 t/ha liner). The greatest difference between liner and
hybrid varieties was observed in plant height. The hybrids reached 10 cm higher on the
average than liner varieties.
The second hypothesis about the similar oil content of hybrid and liner varietes was
confirmed. Observed varieties reached both 43,3 % of oil content .
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