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Research was conducted to investigate the theory of critical thickness h(sub c) and strain relaxation in Ge(sub x)Si(sub 1-x)/Si and In(sub x)Ga(sub 1-x)As/GaAs epilayers. A comparison of the experimental data with theoretical data was performed on a variety of alloys and semiconductors with the values of h(sub c) found to be larger than the calculated values. The discrepancy is blamed on the difficulty in nucleating the dislocations.

Theoretical studies of the heterogeneous nucleation of dislocation loops at the defect clusters of strained epitaxial layers reveal that defect clusters with a small radius are capable of decreasing activation energy from 200 eV to 2 eV with a mismatch of about 1% to enable nucleation of the loops. The decrease in the activation energy is more profound and faster in the 60 degrees loops than in the 90 degrees loops. Layers with very high mismatch of 4% to 8% display homogeneous nucleation between 400 and 500 degrees Celsius.

The interactions between an infinite array of nonperiodic dislocations in semiconductor strained epilayers are investigated. Two types of distributions,namely: the uniform-random and the Gaussian distributions, are used to calculate the energies of the arrays of dislocations. Results reveal that the energy of the dislocation arrays and the total energy of the epilayers are modified considerably by the nonperiodic distribution of the dislocations.

A survey of 142 computer professionals and managers reveals the values held by the individuals. Results of the research have implications for the development of corporate institutions and culture. Respondents were classified according to Graves' existence levels: tribalistic, egocentric, conformist, manipulative, sociocentric, and existential. Results show that the existential level predominates over other levels and is ranked highest for items involved with boss, health, systems and procedures, and job freedom. Results also indicate that there are differences between the way people use values to evaluate others and themselves, between the way values are stated and practiced, and between specific-level choices and conceptual-level preferences.