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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.
61

Problematika uvádění obráběcích center na trh Evropské unie a Společenství nezávislých států / The issue of placing machining centers on the market of the European Union and the Commonwealth of Independent States

Drozdov, Filipp January 2020 (has links)
This thesis discusses introducing CNC machining centers to the markets of the European Union and the Commonwealth of Independent States (currently the Eurasian Economic Union). The first chapter of the thesis focuses on the legal requirements for placing the products on the markets of the European Union and the Eurasian Economic Union, their comparison, systematic analysis of the problem, and certification schemes. The second chapter of the thesis analyses safety requirements for CNC machining centers, discusses CNC machines checklists development and their comparison for the markets of the European Union and the Eurasian Economic Union.
62

Porovnání postojů žáků ZŠ a SŠ k velkým šelmám zejména pak k vlku obecnému (Canis lupus) a psu domácímu (Canis lupus familiaris) / Comparison of Attitudes of Primary and Secondary Schools Students to Large Carnivores, Especially the Common Wolf (Canis lupus) and Domestic Dog (Canis lupus familiaris)

Mejzr, Martin January 2012 (has links)
Today, the issues related to the presence of bears and wolves in the Czech Republic are more frequently discussed due to their occasional occurrence. The significant part of the public still considers these predators dangerous and they even think that a man is supposed to be their potential prey. A lot of surveys confirming this have been already taken, but none of them was focused on the views of primary and secondary schools students. As they are a part of the school education system, their views on the large carnivores should be mainly shaped by it. A questionnaire-based survey was used to find the attitudes of students. The first part of the questionnaire focused on the students' opinions about the dangerousness of predators, its reasons and common wolf presence in the Czech Republic. The second part of the questionnaire is focused on the domestic dog, which has wolf origins. It deals mainly with the attitudes of students to selected dog breeds, dog domestication awareness and views on the so- called "fighting breeds". This work has been aimed at identification of attitudes of the primary and secondary school students from different regions of the Czech Republic to the selected predators. The survey was also taken at primary schools in the High Tatras Mountains, an area where all the large...
63

Anthropogenic impact on predator guilds and ecosystem processes : Apex predator extinctions, land use and climate change

Pasanen Mortensen, Marianne January 2014 (has links)
Humans affect ecosystems by changing species compositions, landscape and climate. This thesis aims to increase our understanding of anthropogenic effects on mesopredator abundance due to changes in apex predator status, landscape and climate. I show that in Eurasia the abundance of a mesopredator, the red fox (Vulpes vulpes), is limited top-down by the Eurasian lynx (Lynx lynx) and bottom-up by winter severity. However, where lynx has been eradicated, fox abundance is instead related to bottom-factors such as cropland (paper I, II). Fox abundance was highest when croplands constituted 25% of the landscape (paper II). I also project red fox abundance in Sweden over the past 200 years and in future scenarios in relation to lynx density, land use and climate change. The projected fox abundance was highest in 1920, when lynx was eradicated and the proportion of cropland was 22%. In 2010, when lynx had recolonised, the projected fox abundance was lower than in 1920, but higher than in 1830. Future scenarios indicated that lynx abundance must increase in respond to climate change to keep fox at the same density as today. The results suggest a mesopredator release when lynx was eradicated, boosted by land use and climate change, and that changes in bottom-up factors can modify the relative strength of top-down factors (paper IV). From 1846-1922, lynx, wolverine (Gulo gulo) and grey wolf (Canis lupus) declined in Scandinavia due to persecution; however I show that the change in wolverine abundance was positively related to the changes in lynx and wolf abundance. This indicates that wolverine is subsidized by carrions from lynx and wolf kills rather than limited top-down by them (paper III). This thesis illustrates how mesopredator abundance is determined by a combination of top-down and bottom-up processes, and how anthropogenic impacts not only can change the structures of predator guilds, but also may modify top-down processes through changes in bottom-up factors. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 3: Submitted. Paper 4: Manuscript.</p><p> </p>
64

Indos, abjects, exiles : Joseph Conrad's culturally liminal characters in the age of nationalism

2013 September 1900 (has links)
This essay is an investigation of transnational author Joseph Conrad’s engagement with issues of cultural liminality during the years around the turn of the 20th century. Through an examination of Almayer from Almayer’s Folly, Yanko of “Amy Foster”, and Cornelius from Lord Jim, the common experience of cultural displacement is considered. Conrad placed these three culturally liminal characters in various, carefully constructed social environments. Thus far, these characters have been under investigated in the critical literature, particularly the mixed-culture Almayer and Cornelius. By investigating these three characters and their environments, this essay demonstrates how Conrad depicts cultural displacement in the age of nationalism to be increasingly multifaceted but inevitably disastrous. The essay further reveals the need for more careful critical assessments of the cultural nuances of Conrad’s characters.
65

Compositional clues to sources and sinks of terrestrial organic matter transported to the Eurasian Arctic shelf

Karlsson, Emma January 2015 (has links)
The amount of organic carbon (OC) present in Siberian Arctic permafrost soils is estimated at twice the amount of carbon currently in the atmosphere. The shelf seas of the Arctic Ocean receive large amounts of this terrestrial OC from Eurasian Arctic rivers and from coastal erosion. Degradation of this land-derived material in the sea would result in the production of dissolved carbon dioxide and may then add to the atmospheric carbon dioxide reservoir. Observations from the Siberian Arctic suggest that transfer of carbon from land to the marine environment is accelerating. However, it is not clear how much of the transported OC is degraded and oxidized, nor how much is removed from the active carbon cycle by burial in marine sediment. Using bulk geochemical parameters, total OC, d13C and D14C isotope composition, and specific molecular markers of plant wax lipids and lignin phenols, the abundance and composition of OC was determined in both dissolved and particulate carrier phases: the colloidal OC (COC; part of the dissolved OC), particulate OC (POC), and sedimentary OC (SOC). Statistical modelling was used to quantify the relative contribution of OC sources to these phases. Terrestrial OC is derived from the seasonally thawing top layer of permafrost soil (topsoil OC) and frozen OC derived from beneath the active layer eroded at the coast, commonly identified as yedoma ice complex deposit OC (yedoma ICD-OC). These carbon pools are transported differently in the aquatic conduits. Topsoil OC was found in young DOC and POC, in the river water, and the shelf water column, suggesting long-distance transport of this fraction. The yedoma ICD-OC was found as old particulate OC that settles out rapidly to the underlying sediment and is laterally transported across the shelf, likely dispersed by bottom nepheloid layer transport or via ice rafting. These two modes of OC transport resulted in different degradation states of topsoil OC and yedoma ICD-OC. Terrestrial CuO oxidation derived biomarkers indicated a highly degraded component in the COC. In contrast, the terrestrial component of the SOC was much less degraded. In line with earlier suggestions the mineral component in yedoma ICD functions as weight and surface protection of the associated OC, which led to burial in the sediment, and limited OC degradation. The degradability of the terrestrial OC in shelf sediment was also addressed in direct incubation studies. Molecular markers indicate marine OC (from primary production) was more readily degraded than terrestrial OC. Degradation was also faster in sediment from the East Siberian Sea, where the marine contribution was higher compared to the Laptev Sea. Although terrestrial carbon in the sediment was degraded slower, the terrestrial component also contributed to carbon dioxide formation in the incubations of marine sediment. These results contribute to our understanding of the marine fate of land-derived OC from the Siberian Arctic. The mobilization of topsoil OC is expected to grow in magnitude with climate warming and associated active layer deepening. This translocated topsoil OC component was found to be highly degraded, which suggests degradation during transport and a possible contribution to atmospheric carbon dioxide. Similarly, the yedoma ICD-OC (and or old mineral soil carbon) may become a stronger source with accelerated warming, but slow degradation may limit its impact on active carbon cycling in the Siberian Shelf Seas. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.</p>
66

Turkey

Celebi, Yusuf Inan 01 May 2006 (has links) (PDF)
This thesis analyses Turkey&rsquo / s energy policies and Turkey&rsquo / s foreign relations through the energy issues in the Eurasian region. In the first phase, the energy policies implemented by the state and free market orientation in Turkish energy sector will be discussed. The impacts of neo-liberal economic policies, regional organizations (the European Union and OECD), and global finance institutions (International Monetary Fund &ndash / the IMF and the World Bank &ndash / WB) on Turkish energy sub-sectors, particularly since the beginning of the 1980s, will be examined. In the second phase, Turkey&rsquo / s own autonomy and effectiveness within major energy pipeline projects in the Eurasian energy axis will be questioned in the post-Cold War period. Turkey&rsquo / s relations in the energy issues with the European Union, Middle East, Caucasus and Turkic States, Russia and the United States (US) will be discussed. Basic vulnerabilities in Turkish energy sector and possible acquisitions of Turkey through its international energy deals will be emphasized.
67

Indirect effects of invasive species community effects of invasive aquatic plant control and direct and indirect effects of non-native peacock bass /

Kovalenko, Katya, January 2009 (has links)
Thesis (Ph.D.)--Mississippi State University. Department of Wildlife and Fisheries. / Title from title screen. Includes bibliographical references.
68

Entre genre, race et nation : vers une nationalité hybridée : le cas des métis franco-vietnamiens «abandonnés» en Indochine française lors de l’entre-deux-guerres

Deschênes-Boutin, Jérémie 04 1900 (has links)
No description available.
69

A spatial and temporal analysis of the changes in alien macrophyte communities and a baseline assessment of the macroinvertebrates associated with Eurasian watermilfoil, Myriophyllum spicatum L. (Haloragaceae) in the Vaal River

Fordham, Colin Justin January 2012 (has links)
The majority of South Africa’s fresh water (lotic and lentic), is eutrophic and this has resulted in water hyacinth, Eichhornia crassipes (C.Mart.) Solms. (Pontederiaceae) becoming South Africa’s most damaging aquatic macrophyte. Recently however, concerns have also been voiced over the presence of highly invasive submerged macrophyte species, such as Eurasian water-milfoil, Myriophyllum spicatum L. (Haloragaceae) in the Vaal River. Interaction studies between floating and submerged macrophytes have shown that floating macrophyte dominance restricts light penetration into the water column shading out submerged macrophytes while submerged macrophyte dominance reduces nutrient availability in the water column limiting floating macrophyte growth. This cycle ensures that these species cannot coexist in the same habitat for extended periods of time. The aims of this thesis were to: 1. Investigate changes in the historical and current macrophyte dominance in the Vaal River 2. Determine whether these changes could be attributed to stochastic events, such as floods and herbicide control measures. 3. The physio-chemical conditions of the water column, and whether pressure from herbivory by macroinvertebrates had possibly influenced Eurasian water-milfoil’s ability to dominate. Spatial and temporal analysis of satellite imagery revealed that water hyacinth and submerged macrophyte species dominated different regions of the study area over different periods of time from 2006 to 2010. This was significantly correlated with nitrate concentrations of the water column. One of the lower Vaal River Water Management Areas (WMA) had changed from a water hyacinth dominated state in 2006 to an alternative submerged macrophyte dominated stable state in 2008. It was concluded that this change could be attributed to: a stochastic flooding event in 2006; perturbation from integrated control measures implemented against water hyacinth; and low nitrate concentrations of the WMA. The lack of any substantial macroinvertebrate herbivory pressure or control measures implemented against Eurasian water-milfoil, compared to similar surveys conducted in the U.S.A. and its native range in Eurasia was shown to contribute to its dominance. Future successful integrated control programmes, including biological control against Eurasian water-milfoil, could provide the perturbation required to restore the ecosystem. However, without the reduction in nitrate concentration levels, water hyacinth will remain the dominant stable state of the rest of the Vaal River.
70

Validating Citizen Science data for use in the design and management of constructed wetlands: a case study of Tufted Duck and Eurasian Teal.

Chamberlain, Richard January 2018 (has links)
Citizen science offers a potentially powerful tool for the environmental scientist to access large data sets over increasingly greater time scales. Given the ease of which information can be reported or shared online and the increase in community interest there is an overwhelming amount of data available. But two major questions remain; is the data reliable and how is it best used? This study addresses the first question by testing the ability of such data from Artportalen, Sweden’s Species Gateway for reporting observations of birds (and other flora and fauna), to reflect patterns in the presence and absence of breeding records of Tufted Duck (Aythya fuligula) and Eurasian Teal (Annas crecca). This was done by undertaking wetland assessments in a set of constructed wetland sites from Artportalen in Halland, Southern Sweden, with breeding records of the target species. A literature review was also undertaken to explore the existing ecological knowledge of breeding habitat requirements for each species. Physical and biological characteristics from the wetlands visited were then qualitatively compared to the existing ecological knowledge for each species’ preferred breeding habitat. This method resulted in some support for the reliability of this particular Citizen Science data, in that it reflected Tufted Duck’s preference to breed in wetlands closer to the coast, that provided some form of cover or screening around the edges and which had a large proportion of their shoreline bordered by tall emergent vegetation. Conversely, it reflected Eurasian Teal’s preference for inland wetlands that were closer to relatively open natural freshwater bodies, where tall emergent vegetation wasn’t as abundant. How this and other Citizen Science data can be used in the design and management of constructed wetlands for conservation purposes in light of these results is then discussed.

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