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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.
81

Laboratorní studium polní iontové emise z prachových zrn / Laboratory Study of Field Ion Emission from Dust Grain

Jeřáb, Martin January 2011 (has links)
Title: Laboratory study of field ion emission from dust grains Author: Martin Jeřáb Department: Department of Surface and Plasma Science Supervisor: Prof. RNDr. Jana Šafránková, DrSc., KFPP Abstract: Dust particles are common objects in space environment. As a dust particles, we call objects with typical sizes of several atoms up to approximately 100 µm. However, a total mass of dust particles is only about 1% of total mass of our galaxy, the presence of dust particles significantly affects environment. The most interesting is dynamics of dust particles and attached dust charging processes. The presented thesis consists of two main parts. The first part deals with the experimental study of field ion emission. Our measurements have been performed using gold and carbon spherical dust grains. It has been found that during the charging of dust particle using ion gun are the primary ions implanted under the surface of the dust particle from where they are release in the form of neutral gas. This releasing of implanted ions affects field ion emission for several hours. The second part of the thesis describes a development of new experimental apparatus determined to the study of photoemission dust charging and con- sequently to the "true" field ion emission study. Keywords: dust, dusty plasmas, charging properties, field...
82

Nabíjení prachových zrn v ionizovaných prostředích / Charging of dust grains in ionized media

Vaverka, Jakub January 2014 (has links)
No description available.
83

Návrh cestní sítě v komplexní pozemkové úpravě / Proposal of road network for complex land adjustment

FLORIÁN, Ondřej January 2015 (has links)
The main purpose of this thesis was compiling the detailed literature search containing the description of a road network from the historical development point of view, detail characteristics of lane types used in complex land adjustment and the evaluation of the road and lane network as a possible element of erosion control. The main object was the analysis of the road and lane network changes during several historical periods, in which the network was captured, studied and the results were compared. The possible causes of the changes where described for key moments of the historical development. As the location of interest the cadastral area Nakri in Ceske Budejovice district was chosen. For this location the detailed road and lane network analasys shows clear overview of remarkable changes during historical development. A part of this thesis is not only capturing the changes, but also a proposal of resolved complex land adjustment, which is in compliance with latest requirements for proposing a plan of common facilities.
84

Vliv intenzity hospodaření a biotopové struktury na ptačí společenstva v zemědělské krajině

KALINOVÁ, Karolína January 2018 (has links)
The thesis presents data from bird monitoring, carried out in agricultural landscape in borderland of Southern Moravia (Czech republic) and Lower Austria (Austria). Relations among habitats and bird species richness and abundance are studied and data from both countries compared.
85

Využití a zpracování historických mapových podkladů pro projektování komplexních pozemkových úprav. / Use and application of historical maps for land consolidation projekt.

KOUBOVÁ, Veronika January 2009 (has links)
This diploma thesis deals with usage and processing historical maps. The main attention was given to the maps of Stable Cadaster and Land Cadaster, which are mostly used for this purpose. The part of the cadastral unit Dříteň {--} Velice was chosen as given locality, where was realized the land adjustment.
86

Kondiční závislost druhotných ornamentů a výběr partnera u koroptve polní Perdix perdix) / Condition dependence of secondary ornamentation and mate choice in Grey Partridges

Gabrielová, Barbora January 2012 (has links)
This study focuses on relationships between individual condition, measures of ornament expression and mate choice in the Grey Partridge (Perdix perdix). It is based on the correlative data as well as results of manipulative experiments. I found positive correlation between the size of melanin- and carotenoid-based ornaments in partridges. The size and the redness of the carotenoid skin patch, and the size of the melanin-based feather ornamentation were associated with several measures of immunity and overall body condition (complement activity, ratio of immature erythrocytes, heterophil/leucocyte ratio, response to novel antigen). Furthermore, data from natural populations indicate that the expression of carotenoid-based ornamentation is associated with sexual attractiveness (measured as the ability to obtain a social mate) in partridges. Data from captive individuals indicate that carotenoid supplementation improves the redness of carotenoid-based ornament, while the stimulation of the immune system under increasing concentrations of supplemented carotenoids has no measurable effect on condition and physiological state. This seems to contradict predictions of the 'Carotenoid maintenance hypothesis'. Overall, results better understanding the role of carotenoid and melanin-based ornamentation in signaling...
87

Rizika predace hnízd koroptve polní (Perdix perdix) / Nest predation risk in Grey Partridge (Perdix perdix)

Holomek, Stanislav January 2013 (has links)
The gray partridge (Perdix perdix) is a bird species living in hiding and nesting on the ground in the open landscape. Even though this species uses several well-known anti-predator adaptations and strategies, its nests are often predated. The range of nest predators and the circumstances of predation have not, however, been satisfactorily described yet. This diploma thesis summarizes the results of experiments carried out on artificial nests and is supplemented by the description of nest behaviour of two incubing hens obtained from video shooting their nests. This work also includes the results of video shoots of predators on artificial nests, the most common of them being the marten. The successful survival of nests in all experiments was influenced mainly by hiding the nest in vegetation. However, the presence of feather odour of adult birds increased the risks of predation even for well-hidden nests. Nests placed in grass biotopes survived the best regardless their covering. What mattered most in other biotopes (along the edges of field roads, forests or groves and field biotopes off any lines) was the covering of nests with vegetation. Partridges nesting close to the edge of a forest or a grove are not very safe from predators. The fact that both nesting partridges and nest predators prefer a...
88

Příprava mikrosatelitových markerů pro studium koroptve polní (Perdix perdix) / Development of Grey Partridge (Perdix perdix) microsatellite markers

Vaněčková, Dominika January 2011 (has links)
The aim of this work was the construction of set of microsatellites for the Grey Partridge (Perdix perdix). I succeeded in isolation of seven new specific microsatellites. Another microsatellite markers were passed from close relative galliform species (Galliformes). On the whole I gained 18 microsatellite loci which were used for study of population charakteristics of three partridge populations from Stodůlky, Písecko and Milešín. The analysis showed conspicuous structuredness of these populations and surprisingly low values (less then 100) of their effective population sizes. Seven of the microsatellites were chosen for analysis of paternity. Indeed I found the evidence of extrapair paternity in this putatively monogamous bird. Finally I conclude, on the basis of sequenation of mitochondrial control region that our populations belong to the western linage of mitochondrial DNA.
89

Analýza realizovaných společných zařízení v pozemkových úpravách ve vybraných k.ú. okresu Tábor / The realization of common facilities in landscape planning in selected areas of Tábor district

SEKALOVÁ, Martina January 2015 (has links)
The realization of common facilities in landscape planning was evaluated in three areas of Tábor district: Sudoměřice near Tábor, Prudice and Libějice. Realization of landscape planning had been completed in these areas nine years before the evaluation. The evaluation consisted of detailed analysis of common facilities in landscape planning project and their comparison with current realized situation. A special emphasis was given to reconstructed and newly constructed elements and to neglected elements in landscape planning. The results were conveyed to tables and graphs that inform about a proportion of realized and unrealized elements and point out that the proportion of realized facilities was insufficient. The theses is concluded by a summary of results and by a list of proposals that would lead to a landscape improvement.
90

Biotopové nároky synantropních ptáků (vrabec domácí, vrabec polní a hrdlička zahradní)

MACHOVÁ, Markéta January 2017 (has links)
Aim of this study was to assess distribution and abundance of common synanthropic species of birds (House sparrow, Tree sparrow, Eurasian collared dove and Blackbird) in area of the city České Budějovice in the Czech Republic in autumn and winter. Habitat preferences of these species were analysed. Study also determined influence of the certain characteristics of urban vegetation on their occupation by both species of sparrows.

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