Soil nitrate-nitrogen (NO3-N) data arranged on a three-dimensional grid were analyzed to compare tillage effect on the spatial distribution of residual NO3-N in the soil profile of agricultural plots drained by subsurface tiles. A three-dimensional median-based resistant (to outlier(s)) approach was developed to polish the spatially located data on soil NO3-N affected by directional trends (non...

Improving green total factor productivity (GTFP) is the key for China’s mineral resources industry to get out of dilemma resource depletion and environmental degradation. The Super Slacks-Based Measure (Super-SBM) model with undesirable output used calculate GTFP between 2004 2019, space–time correlation threshold quantitatively determined by semivariogram. On this basis, spatial weight matrix ...

Some observations are more variable in space and relatively less variable in time or vice versa. Based on the major source of variability, regionalized variable theory is used to construct either spatial or temporal semivariograms. Examples include georeferenced soil data, with primarily spatial variability, and daily weather data, with primarily temporal variability, as input to dynamic simula...

Randommeasurement errors in digital terrain models are important to their quality. The present paper describes an untypical use of variograms to compute this kind of measurement errors. After subtracting a low frequency drift from depth/height measurements, a variogram analysis of the residuals is used to derive the random measurement errors of the observations. Numerical experiments on laserca...

the objectives of this study were to 1) describe the risk factors, incidence, production and reproduction consequences of retained placenta in dairy cows, and 2) estimate the financial losses associated with retained placenta. calving records from march 2008 to december 2013 comprising 59,341 calving were included in the data set. the effects of risk factors on retained placenta incidence were ...