Techniques for Quality Control in Football Field Located in Agricultural Area

摘要

A set of eight sprinklers was evaluated in a soccer field located in the city of Cascavel, Paraná, Brazil, using quality control techniques. The graph X (Shewhart’s individual control card), the EWMA graph (exponentially weighted moving average) and the CUSUM tabular graph (cumulative sum) were used. The system was composed of two parallel lateral lines distanced of 18 meters, containing five sprinklers in each line every 18 meters. The first four sprinklers (area A) and the last four (area B) were evaluated with 25 trials of 10 minutes of irrigation for each area, with the monitoring of climatic effects. For the evaluation of the system, the distribution uniformity coefficient (DU) was used, obtaining in the area A and B the values of 68.72 and 70.0%. This low value can be justified by the high wind velocity during the tests, that varied from 0.57 to 8.5 m s-1. By Shewhart’s control chart, the irrigations of both areas were under control. From the CUSUM chart, only area B was under control. From the EWMA chart, both areas were out of control, being considered the most suitable for evaluation of the system because it detected the small variations in the process.