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Určení polohy stanic v síti Internet pomocí přenosového zpoždění / Geolocation of Internet nodes based on communication latencyHorák, Michael January 2013 (has links)
This thesis covers the topic of determination of geographical location of a host in internet network while utilizing measurement of the end to end delay and implementation of Constraint-Based Geolocation. Gradually I go through issue of the delay in computer networks and ways how to measure it. Next chapter describes a few ways to geolocate host in internet network with emphasis on the CBG method. Another chapter is dedicated to describing a way to project spherical coordinates to the two dimensional space, which has been used in implementation of geolocation method. Chapter about implementation builds upon the facts given in previous chapters while functions of the program written in the JAVA programing language are being explained. Two similar geolocation methods were implemented. By comparing the results gained by implementation, new method of geolocation is proposed and devised. It combines properities of both previous methods. There are results of the implemented methods and their comparation to the one of the source documents used in creation of this thesis in summary section.
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The Influence of the Projected Coordinate System on Animal Home Range Estimation AreaBarr, Michael 04 November 2014 (has links)
Animal home range estimations are important for conservation planning and protecting the habitat of threatened species. The accuracy of home range calculations is influenced by the map projection chosen in a geographic information system (GIS) for data analysis. Different methods of projection will distort spatial data in different ways, so it is important to choose a projection that meets the needs of the research. The large number of projections in use today and the lack of distortion comparison between the various types make selecting the most appropriate projection a difficult decision. The purpose of this study is to quantify and compare the amount of area distortion in animal home range estimations when projected into a number of projected coordinate systems in order to understand how the chosen projection influences analysis. The objectives of this research are accomplished by analyzing the tracking data of four species from different regions in North and South America. The home range of each individual from the four species datasets is calculated using the Characteristic Hull Polygon method for home range estimation and then projected into eight projected coordinate systems of various scales and projection type, including equal area, conformal, equidistant, and compromise projections. A continental Albers Equal Area projection is then used as a baseline area for the calculation of a distortion measurement ratio and magnitude of distortion statistic. The distortion measurement ratio and magnitude calculations provide a measurement of the quantity of area distortion caused by a projection. Results show the amount distortion associated with each type of projection method and how the amount of distortion changes for a projection based on geographic location. These findings show how the choice of map projection can have a large influence on data analysis and illustrate the importance of using an appropriate PCS for the needs of a given study. Distorted perceptions can influence decision-making, so it is important to recognize how a map projection can influence the analysis and interpretation of spatial data.
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Education through Maps : The Challenges of Knowing and Understanding the WorldHennerdal, Pontus January 2015 (has links)
The overall purpose of this thesis is to study, in relation to geography education and with a historical perspective, the challenges of knowing and understanding the world. The cases are all from Sweden. In the first paper, educational ideas in the nineteenth and early twentieth centuries are studied, and the results indicate that some of the previously criticised educational ideas that were perceived as resulting from the ideas of nineteenth century regional geography in fact can be observed in earlier centuries and were criticised during the nineteenth century. In the second paper, school children’s ability to locate geographical names on outline maps is compared with children’s ability to complete the same task 45 years earlier. A total of 1,124 students were included in the latter study, and the results were compared with those from a study of 1,200 students from the same town conducted in 1968. The results raise questions regarding the picture of the continuous decline in children’s school results and show, for example, that children today are better at locating continents on a world map. The final paper identifies a new aspect of map reading difficulties. These difficulties in map reading are increasingly important in our global society, i.e., how the edges of the world map cohere. The paper shows that many map readers, children and adults, respond according to the idea of linear peripheral continuity, which indicates that the proposed continuation is along the straight line that continues tangentially to the original route when it crosses the edge. In general, this understanding leads to incorrect interpretations of the continuation of world maps. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 2: Accepted.</p>
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