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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.
111

Fuzzygeoprvky v rastrové reprezentaci pro podporu rozhodování

Machalová, Jitka January 2003 (has links)
No description available.
112

Podpora rozhodování v prostředí GIS a její aplikace do managementu krajiny

Pechanec, Vilém January 2005 (has links)
No description available.
113

Geographic information system (GIS) integration of geological, geochemical and geophysical data from the Aggeneys base metal province, South Africa

Naicker, Isayvani January 1994 (has links)
Geographic Information System (GIS) technology aids in storage, manipulation, processing, analysis and presentation of spatial data sets. GIS can effectively interrogate large multidisciplinary exploration data sets in the search for new mineral exploitation targets. A spatial database, the AGGeneys Exploration Database (AGGED), has been created, comprising exploration data gathered during two decades of exploration for base-metals in the Aggeneys area, Bushmanland, South Africa. AGGED includes data extracted from analog maps, as well as digital remotely sensed sources, stored in vector and raster data structures, respectively. Vector data includes field based observations such as the extent of outcropping geological units, litho- and chrono-stratigraphic data; structural data; laboratory data based on regional geochemical stream sediment and traverse sampling; cadastral data and known mineral occurrences. Raster data includes Landsat satellite TM imagery and airborne magnetic data. Spatial variation within single data maps are examined. Spatial correlation between three different data maps are facilitated using colour analysis of hue, saturation and value components in a perceptual colour model. Simultaneously combining lead and zinc data with Landsat TM and geophysical magnetic data spatially delineates four new "geoscience" anomalies in the area under investigation. Two distinctive anomalies occur on the farms Aroams and Aggeneys. The Aroams anomaly (GSAl) has not been previously recognised, whereas the Aggeneys anomaly (GSA2) has been located before. The two other "geoscience" anomalies, on the farm Haramoep (GSA3 and GSA4 ), are slightly less distinct. Overlaying fold axial trace patterns and anomalies on the farm Haramoep, indicate that F2 and F3 fold structures are closely associated with these two anomalies. The location of the Aroams anomaly occurs along the same east-west trend of the four known major ore-deposits viz. Big Syncline, Broken Hill, Black Mountain and Gamsberg. Extrapolating F2 and F3 fold patterns using magnetic data locates this Aroams anomaly along the F3 axial trace extending from Big Syncline through to Gamsberg. The elevated Pb-Zn geochemical anomaly and structural data associated with the Aroams anomaly makes it a promising future exploitation target. The AGGED database can be expanded both in geographic extent to include surrounding areas, and to allow for inclusion of future surveys. Analytical processing of data in AGGED can also be continued and expanded. GIS is a burgeoning field and developments in GIS technology will impact on the explorationist. Developments in object-oriented and knowledge-based database technologies, visualisation techniques and artificial intelligence, incorporated in future GIS need to be closely monitored and evaluated by geoscience explorationists.
114

The development of a Geographic information system for environmental monitoring on the Cape Peninsula, and an assessment of the use of spot imagery for vegetation mapping

Webster, Michael S January 1991 (has links)
This thesis concerns the establishment of a Geographic Information System for the Cape Peninsula and the use of SPOT satellite imagery to map land cover classes. The former is seen as a necessary tool to promote judicious conservation management decisions for the fragile "Fynbos" ecosystem, and the latter as a convenient means of acquiring up-to-date information concerning the environment, and to monitor change.
115

Identifying Potential Sedimentation Sources through a Remote Sensing and Gis Analysis of Landuse/Landcover for the Weeks Bay Watershed, Baldwin County, Alabama

Cartwright, John Harrison 03 August 2002 (has links)
The Weeks Bay watershed in Baldwin County, Alabama has experienced rapid changes in landuse/ landcover (LULC) from 1990 to 2000. These changes have resulted in increased upland erosion and higher concentrations of suspended sediment within the watershed. For this research project a spatial model was developed to identify potential sources of sediment relevant to LULC and slope. Landsat satellite imagery was classified to assess LULC within the Weeks Bay watershed. The classification includes forested vegetation, herbaceous vegetation (seasonal and persistent), mixed/ transitional vegetation, urban/ built-up areas, sparse/ residual vegetation and water, with an overall accuracy of 78%. Change detections of the classified images yielded substantial increases in urban areas (92.5%). These data were coupled with slope data in a geographic information system and a raster analysis provided a qualitative evaluation of potential sediment sources within the Weeks Bay watershed based on the change in LULC and slopes of the landscape.
116

Predictive modeling of archaeological site location in Cuba

Unknown Date (has links)
This work aimed at aiding academic and CRM professionals in archaeology by developing a predictive model of prehistoric sites on the southeastern coast of Cuba. The variables in this model were identified by previous archaeological research at Guantâanamo Bay Naval Station. Both GIS analysis and weights of evidence testing were conducted on the model. The results of the GIS and statistical analysis allowed for refinement of the model. Cuba is central to understanding the prehistoric settlement of the Caribbean. The model explored not only site occurrence and environmental correlations, but also looked at intersite correlations. It was determined that site occurrences are strongly linked to low elevation, proximity to other sites, south-facing areas, mangroves, and geologic formations. This model may add to the understanding of the prehistoric settling of Cuba, as well as the interactions between native groups. / by April A. Watson. / Thesis (M.A.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
117

Correlations of sea surface height and solid earth tides with seismicity in the equatorial Pacific Ocean : a GIS approach

Zennaro, Barbara 17 February 2006 (has links)
In the equatorial Pacific Ocean, earthquakes are used as an indicator of tectonic stress for normal faults in the Galapagos Spreading Center, transform faults along the East Pacific Rise and thrust faults in the Middle American subduction zone. Linkages between seafloor tectonic processes and oceanographic and lunar conditions were explored using time-series cross-correlation analyses on two different time scales. Data for earthquakes in the eastern tropical Pacific study area are obtained using the hydrophone arrays of the NOAA-VENTS Program. Hydroacoustic monitoring (listening to underwater sounds) provides scientists with a detailed dataset that includes even small earthquakes, starting as low as magnitude 0.6, that are not perceived by land-based seismographs. Data for sea surface heights (SSH) consist of two different datasets. On a moon's quarter time scale, SSH data used to investigate the influence of the earth tide and changes in oceanic conditions were remotely acquired by the altimeter on board the TOPEX/Poseidon (T/P) satellite. SSH data used to investigate the influence of the ocean tides were obtained from the Tidal Model Driver (Padman and Erofeeva 2003), that predicts SSH for locations every hour. The Geographic Information System (GIS) was used for the visual display of the data and to compute basic descriptive statistics. A lab-book was created for the educational-outreach section of this work, explaining step by step how GIS has been used. Significant results show correlations between normal faults and ocean tides and between the thrust fault and earth tides. Also, the Quebrada and the Discovery transform faults show high correlation of earthquake events, suggesting that at such temporal and spatial resolution, the plate moves as a rigid block. / Graduation date: 2006
118

GIS flood modeling in Indianapolis, Indiana / Geographic information systems flood modeling in Indianapolis, Indiana

Ma, Qian 20 July 2013 (has links)
Access to abstract permanently restricted to Ball State community only. / Access to thesis permanently restricted to Ball State community only. / Department of Geography
119

Quantitative characterisation of channel sinuosity, determination of catchment and sedimentary basin controls on channel sinuosity and interpretation of channel planform in fluvial systems with GIS and remote sensing techniques

Afolabi, Olamide January 2015 (has links)
This work have quantitatively determine the catchment variables controlling the sinuosity transition of non-valley constrained DFS channels in Alaska, Himalaya and the Andes. Results from the characterisation of channel sinuosity were used through regression analyses to determine the catchment and channel bed parameters controlling reach sinuosity trend and transition of fluvial channel planforms in order to infer a control on the heterogeneity of DFS in the rock record. The catchment approach used was necessary because the studied fluvial systems are associated with DFS (which are regarded as larger forms of alluvial fans) and catchment based approach have been used to investigate controls on alluvial fan morphology. In addition, catchment based investigations are rare in the analyses of the discriminant functions that are considered as controlling factors on channel sinuosity and planform employed previously in the tributary systems. Two distinct channel types were found through the characterisation of 553 reaches of fluvial channels in 3 different modern continental sedimentary basins; channels with no transition in sinuosity/planform (group 1), and channels with transition in sinuosity/planform (group 2) Among the channel bed and catchment quantitative variables investigated in this work, catchment area is the only parameter that shows a general relationship with the channel distance from the apex to the transition point in channel sinuosity through the overall regression results. The result shows that the bigger the catchment area the longer the transition point which is related to a higher water and sediment discharge. Thus, the point at which the channel sinuosity transition will occur can be predicted from the catchment area through the regression equation [y=0.0017x + 28] of the overall linear regression line, where x is the catchment area and y is the channel distance from the apex to the point of transition in channel sinuosity. As the studied channels are associated with DFS, this relation also reflects the prediction of the transition point in the DFS fluvial styles in the rock record. Overall regression analysis results show statistically poor results for the relationship between catchment elevation, catchment slope, channel bed elevation, channel bed slope and either the channel sinuosity or the sinuosity transition. However, in all the three study areas, the majority of the datasets show a trend with the catchment area/sinuosity transition relationship. Additionally, the study area with mainly the biggest catchments (longer channel sinuosity transition) is associated with the highest catchment slope, lowest channel bed elevation and more anabranching channels. Also, the study area with mainly the smallest catchments (shorter channel sinuosity transition) is associated with lower catchment slope, higher channel bed elevation and fewer anabranching channels. This suggests that the higher water and sediment discharge may be related to the steeper slopes and the anabranching channels may reflect the lower channel bed elevation. However, deviations obeserved in the overall regression result in the three study areas are attributed to the differences in the climatic, geologic and tectonic factors in the 3 settings. Although, the differences in these study areas have been shown, nevertheless the interpretations cannot be substantiated in this work with the available data. Thus, there is need for further research to prove any conclusive relationship between these factors and hence remains an issue of debate. In conclusion, this work shows that catchment area is an important controlling parameter on the transition in channel sinuosity of non-valley constrained DFS channels and consequently reflects a a control on the transition in spatial variations of the associated DFS in the rock record.
120

Uncertainty and fitness-for-use in handling aerial photographic interpretive data in geographical information systems

Brimicombe, A. J. January 1994 (has links)
published_or_final_version / Geography and Geology / Doctoral / Doctor of Philosophy

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