Cost-benefit analysis for software process improvement

Justification of investments to improve software development processes and technol- ogy continues to be a significant challenge for software management. Managers interested in improving quality, cost, and cycle-time of their products have a large set of methods, tools, and techniques from which to choose. The implementation of one or more of these potential improvements can require considerable time and cost. Decision makers must be able to understand the benefits from each proposed improvement and decide which improvements to implement. While a variety of approaches exist for evaluating the costs and benefits of a few specific improvements such as inspections or systematic reuse, there is no general model for evaluating software process improvements. The result of this research is a practical, useful framework to assist practitioners in evaluating potential process improvements. This general framework can accommodate a variety of methods for estimating the cost-benefit effects of a process change. To illustrate this framework a set of cost-benefit templates for Emerald and Cleanroom technologies were developed and validated. Methods for evaluating effects range from constants and simple equations to bayesian decision models and dynamic process simulations. A prototype tool was developed to assist in performing cost-benefit analysis of software process improvements

Future technology pathways of terrestrial III–V multijunction solar cells for concentrator photovoltaic systems

Future terrestrial concentrator cells will likely feature four or more junctions. The better division of the solar spectrum and the lower current densities in these new multijunction cells reduce the resistive power loss (I^(2)R) and provide a significant advantage in achieving higher efficiencies of 45–50%. The component subcells of these concentrator cells will likely utilize new technology pathways such as highly metamorphic materials, inverted crystal growth, direct-wafer bonding, and their combinations to achieve the desired bandgaps while maintaining excellent device material quality for optimal solar energy conversion. Here, we report preliminary results of two technical approaches: (1) metamorphic ~1 eV GaInAs subcells in conjunction with an inverted growth approach and (2) multijunction cells on wafer-bonded, layer-transferred epitaxial templates