Bioresource and Agricultural Engineering Commons^™

Ventilation System Design Parameters For Greenhouses For Tobacco Production, R. S. Gates, George A. Duncan

Agricultural Engineering Extension Updates

Methods for germination and initial growth of tobacco have changed rapidly in recent years, moving from outside float beds into double-layer plastic greenhouses. Typically, these "tobacco greenhouses" consist of sidewall curtains, which run the entire length of both sides of the house. They may also have modest mechanical ventilation.

Ventilation of greenhouse structures is a mature field, with engineering practices for proper design given by numerous organizations including ASAE. In this article we briefly outline the important features of ventilation of concern to tobacco greenhouse operators.

Effect Of Parameter Distributions On Uncertainty Analysis Of Hydrologic Models, C. Thomas Haan, Daniel E. Storm, T. Al-Issa, Sandeep Prabhu, George J. Sabbagh, Dwayne R. Edwards

Biosystems and Agricultural Engineering Faculty Publications

Increasing concern about the accuracy of hydrologic and water quality models has prompted interest in procedures for evaluating the uncertainty associated with these models. If a Monte Carlo simulation is used in an uncertainty analysis, assumptions must be made relative to the probability distributions to assign to the model input parameters. Some have indicated that since these parameters can not be readily determined, uncertainty analysis is of limited value. In this article we have evaluated the impact of parameter distribution assumptions on estimates of model output uncertainty. We conclude that good estimates of the means and variances of the input …