1. Assoc. Prof. of Civ. Engrg., Univ. of Missouri, Columbia, Mo.
2. Prof. and Chmn. of Civ. Engrg. Dept., Univ. of Missouri, Columbia, Mo.
3. Assoc. Prof. of Agric. Engrg,, Texas A & M College, College Station, Tex,.
4. Highway Research Engr., U.S. Bur. of Pub. Rds., Washington, D. C.