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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.
1

Anatomicko-fyziologická studie kořenů dřevin v jeskyni Cigánská (CHKO Moravský kras)

Plichta, Roman January 2011 (has links)
No description available.
2

Druhové složení bezobratlých při kolonizaci kadáverů v mělkých hrobech / Species composition of invertebrates during cadavers colonizatin in shallow graves

Pikal, Lukáš January 2016 (has links)
In this work, I deal with forensic entomology and representation of invertebrates species which colonise carcasses found in shallow graves, covered with a layer of soil. There was a field experiment conducted from mid-May 2015 to mid-September 2015 for the purpose of this topic. It took place in the Bohemian Forest, known in Czech as Šumava, in the Kundratice village, where shallow graves were dug in the garden of a family house. There were 12 graves in total. There was a carcass of domestic fowl (Gallus gallus f. domestica, Linné, 1758), each weighing about 2 kg, inserted into each grave and then buried. The distance between the graves was 1.5 m. All the individuals of domestic fowl were killed in the same way under the same conditions. The individual graves were divided into four sectors, each sector containing graves with depths of 10 cm, 30 cm, and 50 cm. Subsequently, one sector was dug up every month, and all developmental stages of insects were picked up from each depth, and the samples were then sorted according to whether they were found in the soil or on the carcase itself. The identified samples were then determined by a specialist. Finally, the findings were compared with literary sources and either refuted or confirmed. The experiment has verified the knowledge that members of the Calliphoridae family do not participate on the decomposing process of buried carcasses.
3

Stav a role invazního mlže slávičky mnohotvárné (Dreissena polymorpha) ve vodárenské nádrži Želivka / State and role of invasive zebra mussel (\kur{Dreissena polymorpha}) in the Želivka Reservoir

MERZOVÁ, Martina January 2017 (has links)
The work is focused on the status and role of zebra mussels (Dreissena polymorpha) in the water reservoir Želivka. Literature review summarizes the basic characteristics of living zebra mussels and its impact on the aquatic ecosystem. Current knowledge about this invasive bivalves show that its presence in the water reservoir has certain advantages, but also disadvantages. The main advantage is that zebra as filtrator, increases the transparency of the water and provides food for the animals living in the aquatic environment, or in its vicinity. Disadvantages are then mainly from the economic point of view, the zebra clogs pipes and thus prevents water flow and attached to marker buoys, fishing nets and attaches to the hulls of ships that can be attacked from the inside. In field part population of zebra mussels was sampled in different parts of the reservoir and identified following parameters (temperature and oxygen stratification, coverage to substrate coverage depending on the depth and the substrate, the length of shells according to the horizontal and vertical gradient filtering capacity and the volume rate). The results showed that the incidence and size of shells affects both horizontal and vertical gradient. Zebra mussels occur most depth 1-9 m on rocky, or stony substrate. The greatest incidence was found at Budeč and at Hráz, where the water is less eutrophic than the Zahrádka. Based on these parameters, and literature data was calculated hypothetical filter capacity and discussed its possible impact on the ecosystem components of the reservoir.
4

Srovnání kořenového systému hybridů trav xFestulolium s rodičovskými druhy

Lukášek, Dominik January 2016 (has links)
Rye grass are common considered optimum grass species for intensive agriculture in area with sufficient rainfall, because they provide a high production of quality forage. Unfortunately, they have lack of resistance to abiotic stresses. With heed to the progress climate change, when these stresses will increase, we are looking for genes from better-adapted species of Festuca. Target features are better use of nitrogen and water to attainment high production of forage, increased tolerance to drought and ability rooting compacted layers of soil. These targets lead to research on growth of roots, which are to fulfil the above written targets in award. Following the research of M. Humphreys we are focused on detailed monitoring root growth of three species xFestulolium and their parent species in the early stages of development in our research. They were tested following grasses: Festuca arundinacea (cv. KORA), Festuca pratensis (cv. PRONELA), Lolium multiflorum (cv. MORAVICE) and xFestulolium (cv. HYKOR, HOSTYN and PRIOR). The chosen the method of cultivation in cylinder with sand in outdoor conditions with fertilization in two doses, corresponding to a total 80 kg N/ha. The experiment was performed in two terms: 21. 5. when 23. 7. 2015 and 21. 9. when 11. 12. 2015. In the first term, growth was limited by high temperatures. In the second term were limiting the contrary low temperatures, especially at the end of vegetation. The evaluated parameters were: maximum depth of rooting, total dry root biomass, total root length, root surface, root volume, the ratio R/S, the dry weight of aboveground biomass, maximum height aboveground biomass, number of tillers, number developed leaves, surfaces of the leaves and root length in individual thickness categories. The length, surface and volume of roots with flat leaves, were evaluated through image analysis scans in program WinRHIZO (Regent Instruments, Canada). In most parameters it was the best Lolium multiflorum MORAVICE with xFestulolium HOSTYN. The differences between them are in most of parameters statistically insignificant (outside the maximum depth of root and flat of leaves, where MORAVICE achieved significantly higher values). Anticipated advantages relating to the growth of strong and deep roots in this experiment did not show. The supposed main reason for the termination of the experiment in the early stage of development.
5

Analýza prací ve výškách a nad volnou hloubkou u Hasičského záchranného sboru České republiky a civilního sektoru / Analysis of work at heights and above free depth at the Fire and Rescue Service of the Czech Republic and the civil sector

Jelen, Martin January 2020 (has links)
Title: Analysis of work at heights and above free depth at the Fire Rescue Service of the Czech Republic and civilian sector Objectives: Describe the current status of work at height in the civilian sector and the Fire Rescue Service of the Czech Republic and compare work at height in the areas: legal regulations, qualification levels, training courses, training centers and equipment. Analyze the height interventions of FRS CR in 2016-2018. Methods: Data collection from internal staff, study of available literature and subsequent research. Comparison of the current situation in given aspects. The analyzes were divided according to the types of interventions, which were given the frequency, location and time distribution in the given years. Results: The results of the diploma thesis are a description of the current state of work at heights and above clear depth for civilian high- altitude and firefighters of the Czech Fire Rescue Service and an analysis of height and above depth interventions at units of Fire Rescue Service of the Czech Republic in 2016, 2017 and 2018. Keywords: Analysis, fireman, height, depth, intervention
6

Statistická hloubka funkcionálních dat / Statistical Depth for Functional Data

Nagy, Stanislav January 2016 (has links)
Statistical data depth is a nonparametric tool applicable to multivariate datasets in an attempt to generalize quantiles to complex data such as random vectors, random functions, or distributions on manifolds and graphs. The main idea is, for a general multivariate space M, to assign to a point x ∈ M and a probability distribution P on M a number D(x; P) ∈ [0, 1] characterizing how "centrally located" x is with respect to P. A point maximizing D(·; P) is then a generalization of the median to M-valued data, and the locus of points whose depth value is greater than a certain threshold constitutes the inner depth-quantile region corresponding to P. In this work, we focus on data depth designed for infinite-dimensional spaces M and functional data. Initially, a review of depth functionals available in the literature is given. The emphasis of the exposition is put on the unification of these diverse concepts from the theoretical point of view. It is shown that most of the established depths fall into the general framework of projection-driven functionals of either integrated, or infimal type. Based on the proposed methodology, characteristics and theoretical properties of all these depths can be evaluated simultaneously. The first part of the work is devoted to the investigation of these theoretical properties,...
7

Vážená hloubka dat a diskriminace založená na hloubce dat / Weighted Data Depth and Depth Based Discrimination

Vencálek, Ondřej January 2011 (has links)
The concept of data depth provides a powerful nonparametric tool for multivariate data analysis. We propose a generalization of the well-known halfspace depth called weighted data depth. The weighted data depth is not affine invariant in general, but it has some useful properties as possible nonconvex central areas. We further discuss application of data depth methodology to solve discrimination problem. Several classifiers based on data depth are reviewed and one new classifier is proposed. The new classifier is a modification of k-nearest- neighbour classifier. Classifiers are compared in a short simulation study. Advantage gained from use of the weighted data depth for discrimination purposes is shown.
8

Vážené poloprostorové hloubky a jejich vlastnosti / Weighted Halfspace Depths and Their Properties

Kotík, Lukáš January 2015 (has links)
Statistical depth functions became well known nonparametric tool of multivariate data analyses. The most known depth functions include the halfspace depth. Although the halfspace depth has many desirable properties, some of its properties may lead to biased and misleading results especially when data are not elliptically symmetric. The thesis introduces 2 new classes of the depth functions. Both classes generalize the halfspace depth. They keep some of its properties and since they more respect the geometric structure of data they usually lead to better results when we deal with non-elliptically symmetric, multimodal or mixed distributions. The idea presented in the thesis is based on replacing the indicator of a halfspace by more general weight function. This provides us with a continuum, especially if conic-section weight functions are used, between a local view of data (e.g. kernel density estimate) and a global view of data as is e.g. provided by the halfspace depth. The rate of localization is determined by the choice of the weight functions and theirs parameters. Properties including the uniform strong consistency of the proposed depth functions are proved in the thesis. Limit distribution is also discussed together with some other data depth related topics (regression depth, functional data depth)...
9

Funkční vlastnosti pracovních nástrojů kypřičů na zpracování půdy / Functional properties of tillers working tools

Hamouz, Karel January 2016 (has links)
This theses provides an overview of tillers´ working tools used in current tillage technologies for soil loosening to varying depths. A more detailed overview was made to describe current solutions for the design of tillers for shallow and medium depths. Literary insights into the quality of work and energy requirements of tillers´ working tools are presented. The work also includes the results of field measurement of draught force and quality evaluation of the work of three selected prototypes of chisel tines. This results were used to find out the relationship between specific draught and soil-aggregate size distribution on different widths of chisels and their working depth. For all widths of tines, a significant growth in specific draught was found with increasing working depth. The specific draught significantly correlated with the cross-section area of the loosened soil (correlation coefficient 0,808).
10

Využití secích strojů pro přípravu půdy při pěstování obilnin / Use of seeding machinery for soil preparation in the cultivation of cereals

JÍRA, Václav January 2014 (has links)
The aim of the thesis is to extend knowledge in terms of the application of modern seeding machinery for soil preparation for sowing in the cultivation of cereals. In the literary section of the report a brief overview of the use of seed drills for minimum tillage. Load small-plot experiment on the selected station and simultaneously perform evaluation activities seeders work to prepare the ground in terms of quality seed, seed depth, coming in plants (growth phase), or the occurrence of weeds. The thesis will brief overview of the analysis of operating costs. The results evaluate and propose recommendations for possible use in agricultural practice.

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