1. a Department of Plant and Soil Sciences , Mississippi State University , Mississippi State , Mississippi , USA
2. b Department of Civil and Environmental Engineering , Tennessee Technological University , Cookeville , Tennessee , USA
3. c Pacific International Engineering , PLLC , Edmonds , Washington , USA
4. d Department of Civil Engineering , University of Technology Malaysia , Skudai , Malaysia
5. e Barr Engineering Company , Minneapolis , Minnesota , USA