Approved for public release, distribution unlimited / The purpose of this thesis is to conduct the research necessary to develop integrated 3D terrain maps capable of supporting an Unmanned Aerial Vehicle Flight Mission Control Support System. In this work, the author has tried to explore the feasibility of exploiting digital topographic maps and further understanding of the digital terrain support available to UAV FMCSS developers. This thesis explores numerous digital terrain data representations and tools available to create digital environments. This work examines and gives a methodology how to find, process, and operate in these environments. To accomplish this, the author explores the more general problem of where to find the data, what tools are available, and how to put the pieces together to create a registered digital environment on a state-of-the-art computer. This work provides a logical construct and design methodology for an analyst to create high fidelity terrain data sets. It functions as a â how toâ manual to help analysts understand which information and tools are available to use for different types of simulation projects.

N/A

The zebrafish visual system relies on positional information in the retina and optic tectum, so that the spatial fidelity of light signals that enter the eye are preserved for visual processing. This positional information is essential for ordered topographic mapping of retinal ganglion cell axons. Spatial information in the retina and tectum relies on discrete signaling pathways that regulate polarized expression of axon guidance molecules in distinct domains in both the retina and tectum, thereby ensuring that accurate topographic maps are created. In this thesis, I have investigated the function of two families of transcription factors, Pbx and Meis, as well as a growth factor of the Bmp family, Gdf6a, in specifying positional identity in the zebrafish visual system. I demonstrate that two partially redundant pbx genes, pbx2 and pbx4, along with members of the meis family, are required for patterning of the dorsal retina and tectum in zebrafish. Embryos lacking these critical transcription factors exhibit retinal ganglion cell axon outgrowth errors, which are likely the result of tectal mis-patterning. Bone morphogenetic protein (Bmp) growth factors regulate dorsal retinal identity in vertebrate models, but the developmental timing of this signaling remains unclear. In this thesis, I investigate the functions of two zebrafish Bmps, Gdf6a and Bmp4, during initiation of dorsal retinal identity. Knockdown of zebrafish Gdf6a blocks initiation of dorsal marker expression, while knockdown of Bmp4 produces no discernable retinal phenotype. These data, combined with analyses of embryos ectopically expressing Bmps, demonstrate that Gdf6a is necessary and sufficient for initiation of dorsal retinal identity, and loss of such identity leads to errors in retinal ganglion cell topographic mapping. Finally, I demonstrate that gdf6a is required for numerous embryonic processes in addition to dorsal retina specification. Gdf6a in required for eye growth, as loss of Gdf6a function leads to microphthalmia. I have obtained preliminary evidence that this growth factor is also required for development of the lens and axial skeleton. Furthermore, many of these phenotypes are similar to those seen in human patients with mutations in GDF6, highlighting the importance of understanding the function of this growth factor in model organisms. / Molecular Biology and Genetics

No description available.

農林水産研究情報センターで作成したPDFファイルを使用している。

N/A

Mountainous regions are ubiquitously dissected by river networks. These networks are the main drivers by which climate and tectonic signals are transmitted to the rest of the landscape, and control the response timescale of the landscape to these external forcings. Furthermore, river systems set the downslope boundary conditions for hillslope sediment transport, which controls landscape denudation. Therefore, understanding the controls on the organisation and structure of river networks in upland landscapes is an important goal in Earth surface processes research. The recent introduction of high-resolution topographic data, such as airborne lidar data, has revolutionised our ability to extract information from the topography, providing new opportunities for linking geomorphic process with landscape form. This thesis is focused on developing techniques for analysing high-resolution topographic data to quantify and understand controls on the structure of fiuvial systems in upland landscapes. Firstly, I develop and test new algorithms for objective feature extraction from lidar-derived digital elevation models (DEMs). I present a new method for identifying the upstream extent of channel processes by identifying scaling breaks in river long profiles. I then compare this new method to three existing methods of channel extraction, using field-mapped channel heads from four field sites in the US. I find that the new method presented here, along with another method of identifying channels based on valley geometry, most accurately reproduces the measured channel heads in all four field sites. I then present a new method for identifying floodplains and fiuvial terraces from DEMs based on two thresholds: local gradient, and elevation compared to the nearest channel. These thresholds are calculated statistically from the DEM using quantile-quantile plots and do not need to be set manually for each landscape in question. I test this new method against field-mapped floodplain initiation points, published flood hazard maps, and digitised terrace surfaces from eight field sites in both the US and the UK. This method provides a new tool for rapidly and objectively identifying floodplain and terrace features on a landscape scale, with applications including flood risk mapping, landscape evolution modelling, and quantification of sediment storage and routing. Finally, I apply these new algorithms to examine the density of channel networks across a range of mountainous landscapes, and explore implications for fluvial incision models. I compare the relationship between drainage density (Dd) and erosion rate (E) using both analytical solutions and numerical modelling, and find that varying the channel slope exponent (n) in detachment-limited fluvial incision models controls the relationship between Dd and E. Following on from this, I quantify Dd for five field sites throughout the US. For two of these field sites I compare Dd to cosmogenic radionuclide (CRN)-derived erosion rates, and for each site I use mean hilltop curvature as a proxy for erosion rate where CRN-derived erosion rates are not available. I find that there is a significant positive relationship between Dd, E, and hilltop curvature across four out of the five field sites. In contrast to assumptions made in many studies of fluvial incision, this positive relationship suggests that the channel slope exponent n is greater than unity for each of these landscapes, with fundamental implications for both landscape evolution and sediment transport.

In 1882, the United States Geological Survey began its National Mappping Program designed to map the nation using a series of several thousand topographic quadrangles. Since that date, the program and the maps themselves have undergone many changes due mainly to technological advances in mapping methods. The use of data collected from historic U.S.G.S. topographic maps in modem day applications necessitates a general knowledge of the potentials and limitations of these data. This study compares representations of terrain features on historic maps compiled using plane table methods with the same features as represented on more accurate modem maps compiled using photogrammetry. Using the modem map as a standard, errors in the old maps were identified and defined using statistical procedures. Measures of closed contour lines recorded the angularity of the line, the length of the line, the area within the contour, the shape of the feature and spatial relationships between contour pairs. The analysis attempts to relate errors to these geometric components of contour lines and to predict the occurrence of error. Due to practices of smoothing and generalization of contour lines in plane table surveys, measures of both angularity and shape were significantly different between older and newer maps. Systematic errors, a consistent displacement of contour lines in a similar direction, were also identified on the historic maps. Based on these results, several suggestions for continuation of the research are given. / Master of Science

The southern Appalachian Mountains have long been an area of interest for the analysis of forest species growth and composition. Past forest vegetation studies focus on species composition and structure for relatively local scale research areas. Species distribution within this geographic area was compiled from studies published from 1956 to 2006. The distribution of hardwood species within the southern Appalachians decreased as the elevation of the sites increased, but this relationship could not be solely attributed to elevation gradient. In order to better understand the relationship between elevation on the radial growth of tree species within the region, an elevation microsite was selected to explore the relationship between elevation and the radial growth of upland oak. Eight study sites across an elevation gradient were selected, and 20 oak tree cores were collected, cross-dated, measured, and a master chronology was created for each site. The correlation between ring width index and Palmer drought severity index (PDSI), precipitation and temperature was calculated with each site's master chronology. There was a significant positive correlation between PDSI and ring width index during the growing season for a majority of the year, and a significant positive correlation between precipitation and ring width index during the growing season. Even though the master chronologies originated from eight separate sites, there were common dendroclimatic responses across seven of the sites. Canonical correspondence analysis of site characteristics and ring width index indicate that the master chronologies can be grouped into three separate chronologies based upon similar environmental and site characteristic responses. / Master of Science

Generalization of Road Network in Topographic Map Abstract The diploma thesis presents automated selection of the elements of path network. The review deals with this term and describes its position in map generalization process; the ways of path thinning apllied in the main Czech cartography institutions are reviewed too. Next part of the thesis describes the data and the tools that are applied in the proposed method. The main part introduces the suggested method of selecting elements of path network which was implemented on the test data. Keywords: map generalization, path network, path thinning, graph theory, ZABAGED, ArcGIS, Python, NetworkX