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Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

1996

Engineering

Stuart J. Birrell

Articles 1 - 5 of 5

Full-Text Articles in Life Sciences

Comparison Of Sensors And Techniques For Crop Yield Mapping, Stuart J. Birrell, Kenneth A. Sudduth, Steven C. Borgett Feb 1996

Comparison Of Sensors And Techniques For Crop Yield Mapping, Stuart J. Birrell, Kenneth A. Sudduth, Steven C. Borgett

Stuart J. Birrell

The implementation of site-specific crop management is dependent on the variations in yield and yield potential within a field. Crop yield maps are important for both the implementation and evaluation of site-specific crop management strategies. Management decisions and evaluations based on yield maps must take into consideration the accuracy and resolution of the maps.

An impact-based yield monitor and a volumetric yield monitor were compared. The effect of different dynamic models of combine grain flow on the calculated instantaneous yields were investigated. Both simple time delay models and first order models could be used to model the grain flow. In …


Evaluation Of Gps For Applications In Precision Agriculture, Steven C. Borgelt, John D. Harrison, Kenneth A. Sudduth, Stuart J. Birrell Jan 1996

Evaluation Of Gps For Applications In Precision Agriculture, Steven C. Borgelt, John D. Harrison, Kenneth A. Sudduth, Stuart J. Birrell

Stuart J. Birrell

Location coordinate information is needed in precision agriculture to map in-field variability, and to serve as a control input for variable rate application. Differential global positioning system (DGPS) measurement techniques were compared with other independent data sources for sample point location and combine yield mapping operations. Sample point location could be determined to within 1 m (3 ft) 2dRMS using C/A code processing techniques and data from a high-performance GPS receiver. Higher accuracies could be obtained with carrier phase kinematic positioning methods, but this required more time and was a less robust technique with a greater potential for data acquisition …


Nutrient Mapping Implications Of Short-Range Variability, Stuart J. Birrell Jan 1996

Nutrient Mapping Implications Of Short-Range Variability, Stuart J. Birrell

Stuart J. Birrell

Successful site specific nutrient application depends on accurate soil nutrient maps, which are generally developed from grid samples. The implication of short range variability for soil nutrient mapping is investigated. Interpretation of soil nutrient maps must consider the level of confidence associated with estimated values.


Analysis Of Spatial Factors Influencing Crop Yield, K. A. Sudduth, S. T. Drummond, Stuart J. Birrell, N. R. Kitchen Jan 1996

Analysis Of Spatial Factors Influencing Crop Yield, K. A. Sudduth, S. T. Drummond, Stuart J. Birrell, N. R. Kitchen

Stuart J. Birrell

The spatial relationship between crop yields and soil and site parameters was modeled using several methods. Yield maps estimated by projection pursuit regression and neural network analysis agreed well with measured yields. These methods also allowed generation of response curves for estimated yield as a function of each of the input parameters. These response curves were useful for investigating the relationship between yields and individual soil and site parameters.


Missouri Precision Agriculture, N. R. Kitchen, K. A. Sudduth, Stuart J. Birrell, S. C. Borgelt Jan 1996

Missouri Precision Agriculture, N. R. Kitchen, K. A. Sudduth, Stuart J. Birrell, S. C. Borgelt

Stuart J. Birrell

A number of projects related to different facets of precision agriculture are being carried out by an interdisciplinary team of scientists and engineers with the University of Missouri and the USDA Agricultural Research Service. This paper provides an overview of those projects.