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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Díla Maffea Pantaleoniho, vybrané otázky / Díla Maffea Pantaleoniho vybrané otázky

Asipkova, Hanna January 2010 (has links)
Diplomová práce je zaměřena na významnou italskou osobnost, Maffeo Pantaleoni, a na jeho velký vklad do italské a světové ekonomie. V práci jsou také popsané dva z mnohých problémů, kterými se zabýval italský ekonom na konci 19. a na počátku 20. století; jeho přátelství s Vilfredem Paretem a o skandálu Římské banky, ve kterém Pantaleoni hrál jednu z hlavních rolí. Maffeo Pantaleoni zdůrazňuje důležitost výchozích a konečných pozic pro ekonomické subjekty v díle Výchozí a konečná pozice. Kde ekonom analyzuje a snaží se aplikovat vzájemné působení výchozích a konečných bodů krátkodobých a dlouhodobých časových intervalů v ekonomickém aspektu pomocí příkladů a alegorie. Pomocí druhého díla Některé fenomény ekonomické dynamiky Maffeo Pantaleoni pokračuje ve studiu ekonomů neoklasiků, kteří přesně definovali pojem statiky, a uvádí a vysvětluje dynamiku druhého druhu. Tady autor klade důraz hlavně na vliv rostoucí poptávky na dimenzi podniku a na rozdělení hlavních a specifických výdajů. V obou případech Maffeo Pantaleoni je proti státnímu zásahu a vystupuje pro "svobodnou" ekonomii.
32

Průzkum dynamiky růstu rychle rostoucích dřevin a jejich využití v krajinářské architektuře

Miksová, Lenka January 2017 (has links)
This thesis focuses on the fast-growing deciduous trees. The literature review summarized the information about fast-growing species, their attributes, advantages, disadvantages, possibilities of utilization (especially in landscape architecture), principles of cultivation. Selected species were described, categorized and the assortment was analysed. The aim of practical part was based on the original field research to evaluate growing dynamics of nine species of deciduous trees (a maximum of ten years after planting). Were assessed 225 trees of the model area in biocentre Ráječek in Brno - Černovice. Following attributes were assessed: height, trunk circumference, annual growth of the terminal and annual growth of six other shoots.
33

Vliv lesních disturbancí na dynamiku odtoku v oblasti centrální Šumavy / Impact of forest disturbances on the runoff in the central Sumava Mts.

Bartůňková, Kristýna January 2011 (has links)
Impact of forrest disturbance on the runoff in the central Šumava Mts. ABSTRACT The diploma thesis deals with the influence of forest disturbance, as for example wind and bark beetle calamities, to the runoff characteristics in the central Šumava Mountains. The analysis of five precipitation events and their runoff responses was applied to seven small experimental catchments with different stage of disturbance. Studied catchments were catchments fo Tmavý, Roklanský, Březnický, Javoří, Cikánský, Černohorský potok and Antýgl. Chosen precipitation events belong to the years 2009 and 2010 and to warm half year, when no snow cover can influence the runoff. Similarity of catchments was established by cluster analysis. For comparison of the reaction of single catchments to the same precipitation event was used simple comparison of precipitation and runoff data and waves. Key words: forest disturbance, central Šumava Mountains, rainfall-flow conditions, cluster analysis
34

Populační trendy živočichů různých taxonů a regionů na základě Living Planet Database / Population trends of animals of different taxa and regions on the basis of the Living Planet Database

Váňová, Lenka January 2021 (has links)
The analysis of population trends of animals is increasingly being used not only as an indicator of population changes, but also as an indicator of biodiversity decline. Living Planet Index is one of such indicators, as it shows a proportional decline or increase of all populations by means of mean annual changes in population abundance. Since the first presentation of the index in 1998, its values have been decreasing, which was interpreted as indication of a critical state of global biodiversity. Nevertheless, there are some issues concerning the index. It is unclear to what extent is it robust, if it is not too much influenced by biased data or if it does not comprise a systematic error. This thesis focuses on four vertebrate taxa and its aim is to examine the level of data heterogeneity and their potential influence on the index. For this purpose, two parameters were defined for each population, Growth and Trend. Overall, the trends in abundances were quite balanced, some populations being decreasing, some increasing, and stable populations were also present. Despite of our expectations, the heterogeneity in the data was not large enough to have a substantial effect on the index. Analysis of trends in variously defined groups (e. g. "biomes", taxa or biogeographic realms) revealed only little...
35

Orbitální a kolizní dynamika malých těles / Orbital and collisional dynamics of small bodies

Rozehnal, Jakub January 2021 (has links)
This work is devoted to a study of dynamical and collisional processes, governing populations of small bodies in the Solar System. It pays special attention to asteroid families and Jupiter Trojans. Librating around L4 and L5 Lagrangian points of the Sun-Jupiter-asteroid system, these asteroids are believed to be captured from the trans- Neptunian region during a giant planet system instability about 4 Gy ago. We discovered (back in 2011) there is only one significant collisional family among Trojans, associated with C-type asteroid (3548) Eurybates, i.e., one of the targets for the upcoming 'Lucy' mission. Detailed analysis of new proper resonant orbital elements, colours and albedos, together with statistical significance computations, allowed us to find five more collisional families: Hektor, (9799), Arkesilaos, Ennomos, and (247341). The discovery of the first D-type family associated with (624) Hektor was the most surprising, because it is the most primitive taxonomic type. Using long-term dynamical simulations of synthetic families, evolving by chaotic diffusion, we estimated the ages of the Eurybates and Hektor families, approximately (2.5±1.5) Gy for both. We also studied impact processes by means of the smoothed-particle hydrodynamics (SPH). We simulated cratering events on (624) Hektor, the origin...
36

Loranthus europaeus Jacq. verzus druhy r. Quercus L. resp. Carpinus L. =:Loranthus europaeus Jacq. vs. Quercus L. resp. Carpinus L. genera. /

Kubíček, Jan January 2018 (has links)
A better understanding of host – hemiparasite association can lead to deepening and improving strategies, which would result in a long-term sustainability of their mutual balance or prosperity of urban and forest vegetation growth. The aim of the thesis is to describe and explore periodicity and dynamics of hemiparasite (Loranthus europaeus Jacq.) on various host woody species (Quercus petraea (Matt) Liebl., Carpinus betulus L., Prunus spinosa L.), options of the host support and means of a careful removal of parasite. However, to determine the progress of the infestation in time was the primary aim of the thesis. The research has been carried out in Brno – Kohoutovice and National Park Podyjí. The emergence of both hemiparasite´s and host´s phenophases were mutually compared in the critical conditions. The variation of the growth modules of mistletoe was compared in relation to the host species. The growth and fruit yield of the host and hemiparasite were analysed after the application of fertilizer based on the variations of the mineral content of leaves and soil. Between the years 2011-2015, 1599 stems were monitored for the degree of infestation by mistletoe. The results indicate that the vitality of the hemiparasite depends on the type of host. Fertilizer application improved the growth of the host. Arboricide application on the leaves of the hemiparasite was proven to be efficient. The abundance of hemiparasite increases with the increasing diameter at breast height (DBH), time and mutual interaction. The amount of hemiparasite slightly increases with the lower DBH. However, with the increasing DBH the mentioned phenomenon decreases. The trees with high DBH even show the decrease in the mistletoe infestation in time. Nevertheless, the decrease was accompanied by negative effect – gradual reduction of the crown and loss of the host tree branches. Hemiparasite is able to eradicate the whole stand. Hence, the necessity of paying attention to this issue since the young age of the individual trees. It is necessary to protect trees against stress aspects which can accelerate the negative effect of hemiparasite on the host.
37

Populační dynamika bolena dravého Leuciscus aspius v údolní nádrži Želivka / Population dynamics of Asp Leuciscus aspius from the Želivka dam

Bouše, Eduard January 2014 (has links)
The aim of this study was to evaluate the material about the asp Leuciscus aspius (L., 1758) from the dam Želivka - Švihov in the years 1971 - 2014. Main emphasis was put on the analysis of the flock spawning from 2008 - 2014. Here, basic abiotic conditions were monitored at the time of the spawning and growth and population characteristics were calculated. Spawning took place at two locations, at 4 - 10 0 C, the asp showed a spawning site accuracy. Males predominated on the spawning grounds in the overall ratio of 1,22 : 1. The age of the fish examined ranged from 3+ to 13+. The average mortality of adults is about 0,4. Additional flock spawning ranges from 20 to 50%. The length at which scales begin to form (SL = 29,7 mm), was determined by using the rate between the body length and scale radius. Differences in the growth rates between males a females are minimal, only from the third to the fifth age group, males showed a higher growth rates. The length - weight relationship can be described as W = 0,0153. L3,19 .
38

Vývoj a aplikace molekulové dynamiky pro chirální systémy / Development and applications of molecular dynamics for chiral systems

Kessler, Jiří January 2012 (has links)
The Thesis deals with MD simulations of solutions of chiral solutes in chiral solvents. These solutions consist of 2,2,2-trifluoro-1-phenylethanol, 1-phenylethanol and 1-phenyl- ethanamine.The differences in NMR properties between different combnations of solvent and solute absolute configuration were modeled. Indeed, differences in radial distribution functions and conformer abundances of solute calculated by the WHAM method were found. These results correlated with experimental differences in NMR shifts. Additionally, a method of cluster preselection was developed. It significantly decreased the amount of clusters needed for computations of NMR shieldings and hence the computer time. Keywords: chirality, molecular dynamic, nuclear magnetic resonance
39

Interakce iontů s proteiny / Ion - Protein Interaction

Heyda, Jan January 2011 (has links)
Title: Ion-Protein Interactions Author: Mgr. et Mgr. Jan Heyda Department: Physical and Macromoleculer Chemistry Advisor: Prof. Pavel Jungwirth, DSc., IOCB AS CR, v.v.i. Advisor's e-mail address: pavel.jungwirth@uochb.cas.cz Abstract: Conventional molecular dynamics simulations in combination with ad- vanced methods of analyses were used to improve the understanding of the interac- tion between ions and proteins in salt solutions. Thus systems of diverse complexity and size were investigated, starting with simple (and molecular) salt solutions with small fragments that mimic the various functional groups of amino acids such as N-methylacetamide representing the peptide bond or alkylated ammonium cations. Continuing with individual positively charged amino acids (arginine, histidine, ly- sine) a strong binding interaction with small fluoride anion that is significantly weak- ened for larger halides (Cl− , Br− , I− ) was described. This observation was extended by detecting the strong sensitivity of fluoride to charge distribution on ammonium, lysine side chain, and the N-terminal of glycine while sensitivity of iodide was found to be low. Later it was shown that the attractive side chain-side chain interactions are significant for short positively charged peptide fragments in polyarginine and dihistidine, while...
40

Populační dynamika bolena dravého Leuciscus aspius (L., 1758) v údolní nádrži Želivka / Population dynamics of Asp Leuciscus aspius ( L., 1758) from the Želivka dam

Bouše, Eduard January 2013 (has links)
The scale material of the asp (Leuciscus aspius, L., 1758) collected from the Želivka dam between 1971 and 2012 has been processed and evaluated. The samples gathered between 2008 and 2012 have been used to determine the basic growth and population characteristics. In the first place I focused on the shoal spawning analysis. The age of individuals in this analysis ranged between 3+ to 13+, at the body length ranging between 370 to 690 mm. The length of the fish when the scales begin to appear (SL = 29,7 mm) was determined on the base of correlation between the body length and the scale radius. The growth rate in recent years was defined using the technique of back - calculation from the scales. The body length-weight relationship can be described as W = 0,009 ∙ L3,1 . The difference in the growth speed between males and females was minimal and statistically inconclusive. The growth speed of an asp in the Želivka dam is roughly at the same level as all other water reservoirs in Czech Republic.

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