Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 12 of 12 for “"Semivariogram"”.
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Spatial Variability Analysis and Reclamation of Saline-Sodic Soils in the Northern Great Plains
… be useful for future study. The exponential semivariogram model was found to be the optimal model for NDVI and yield with the spatial dependence (nugget/sill ratio) of 14.4 and 0%, respectively. Similarly, the exponential model was the optimum fit for mollic depth, lime depth, pH, EC, and SAR …
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Spatio-temporal patterns of soil resources following disturbance in a 40-year-old slash pine (pinus elliottii Engelm.) forest in the Coastal Plain of South Carolina
… than did girdling. Despite the popularity of semivariogram analysis in recent ecological studies, the technique did not provide consistent results on patterns of heterogeneity in our system. A simulation experiment demonstrated that semivariogram analysis may suffer from many problems when it …
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SPATIAL VARIABILITY OF THERMAL PROPERTIES IN RECLAMATION COVER SYSTEMS
… systems of various textures and configurations. Semivariogram analysis demonstrated that on a 40 m slope consisting of mineral soil over sand (Site #1) soil temperatures did not exhibit any spatial structure, due to the presence of vegetation. A 100 m cover system comprised of a structureless …
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Three-Dimensional Distance Based Geostatistical Models to Adjust Radar Rainfall Data
… on the typhoon events, using 3D distances in the semivariogram and Kriging interpolations is shown to be able to produce improved estimations of radar rainfall rates than 2D distance based calculations.
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A comparison of spatial interpolation techniques in temperature estimation
… inverse distance, have lower MAE values. The semivariogram fitting methodology outlined in this dissertation demonstrates how to fit semivariograms iteratively using an indicative goodness of fit (IGF) metric. Semivariogram fitting using an IGF is less subjective and more accurate than …
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Landscape pattern analysis related to forest wildlife resources
… spatial scale influences habitat evaluation. Semivariogram analysis assessed the constancy of expression behavior during changes in scale and presented the limits of tolerance for using large pixels in pattern analyses. The variability observed suggested that pattern misrepresentation occurred …
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Rapid identification of oil contaminated soils using visible near infrared diffuse reflectance spectroscopy
… over an 80 ha study site. An exponential semivariogram using PS predictions revealed strong spatial dependence among soil TPH [r2 = 0.76, range = 52 m, nugget = 0.001 (log10 mg kg-1)2, and sill 1.044 (log10 mg kg-1)2]. An ordinary block kriging map produced from the data showed that TPH …
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Ore Types And Fluid Regimes: Macassa Gold Mine, Kirkland Lake
… which can be approximated by theoretical semivariogram models. However, experimental semivariograms calculated along three principal directions within the type zone: alone strike, across strike, and down dip; have zonal, directional and proportional effect anisotropies.;The (delta)('18)O …
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Recommendations for Data Collection and Analysis During Field Testing of Ground Penetrating Radar Used to Measure Bituminous Asphalt Compaction
… was characterized using the experimental semivariogram. This analysis revealed that the correlation length of the dielectric (and therefore air voids) ranges from 3[ft] to 45[ft] near the centerline joint, and is less than or equal to 13[ft] in the middle of the lane. These relatively …
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Space-time statistical analysis of malaria morbidity incidence cases in Ghana: A geostatistical modelling approach
… the country over the years. The space-time semivariogram models characterising the spatio-temporal continuity of the incidence rates indicated that the occurrence of the malaria morbidity was spatially and temporally correlated within spatial and temporal ranges varying between 30 and 250 km …
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Modelling HIV/AIDS epidemic in Nigeria
… (Moran I and Geary c coefficients, semivariogram and kriging) applied to the National HIV/AIDS Surveillance data. Results revealed the existence of spatial clusters with significant positive spatial autocorrelation coefficients that tended to get stronger as the epidemic developed …
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Optimizing peak gust and maximum sustained wind speed estimates from mid-latitude wave cyclones
… research is needed to merge local-scale semivariograms with continental-scale models. Results showed substantial improvements in wind speed surface estimates over previous estimates and have major implications for catastrophe modeling companies, insurance needs, and construction …