Optimization of Sprinkler Structures to Increase the Water Distribution Uniformity-a Review Optimization of Sprinkler Structures to Increase the Water Distribution Uniformity-a Review Optimization of Sprinkler Structures to Increase the Water Distribution Uniformity-a Review Optimization of Sprinkler Structures to Increase the Water Distribution Uniformity-a Review optimization of sprinkler structures to increase the water distribution uniformity-a review