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He earned his B.Sc. (1982) in Civil Engineering and M.Sc. (1985) in Structural Engineering from Alexandria University, Egypt. He also holds a M.Sc. (1989) and a Ph.D. (1992) in Aerospace Engineering from Georgia Institute of Technology.

Mixed carbonate and siliciclastic marine sediments commonly become freshwater aquifers in eastern coastal regions of the United States and many other global locations. As these deposits age, the carbonate fraction of the sediment is commonly removed by dissolution and the aquifer can become a solely siliciclastic system or contain zones or beds of pure quartz sand. During aquifer evolution, the sediment grain size characteristics, hydraulic conductivity, and porosity change. An investigation of these changes using mixed carbonate/siliciclastic sediment samples collected from a modern barrier island beach in southern Florida showed that the average mean grain diameter decreased with removal of the carbonate fraction, but the average hydraulic conductivity and porosity increased slightly, but not to statistical significance. This counterintuitive result occurs because of the change in the pore types from a combined shelter and intergranular pore system producing a dual porosity system in the mixed sediments to a single intergranular pore system in the siliciclastic sediment fraction. Within the mixed carbonate/siliciclastic sediment, in the pure carbonate fraction, large shell fractions form grain-supported large pores, which become filled with sand-sized quartz as the shell fragments decrease in size or as the sediment becomes compacted. The hydraulic conductivity increases because the shell fragments that were oriented perpendicular to flow caused an increase in the length of the flow path, or a larger scale tortuosity, compared with the flow through pure quartz sand.

In addition to student surveys, evaluation of student performance on both the final papers and final presentations occurred. Performance was measured against established rubrics that were presented to the students early in the semester and are shown in Tables 1 and 2. These rubrics were designed to include sections focusing on points discussed in the course throughout the semester-e.g. APA formatting, scholarly references, effective communication, the NAE Grand Challenges, etc. Students were encouraged to consult these rubrics starting as early as the outline stage, and continuing through draft and final submission preparation. Criteria Longer Description Points Overall Organization Has appropriate sections that flow logically, provide sufficient topic coverage, and are representative of current body of knowledge. Uses scientific language and structure throughout.