A major obstacle stands in the way of implementing any such improvements. Both SRAG and SEC have all they can do just to maintain the data collection and analysis that are needed for ongoing operations. The incorporation of improvements becomes a secondary activity, and the lack of adequate resources and agency support in both organizations is limiting the rate of improvement. Currently, the incorporation of improvements lags far behind taking advantage of new capability. Figure 5.1 illustrates the backlog of models that need to be improved before the ISS radiation environment can be accurately specified and forecast.

The transition to better models is virtually stalled by the full commitment of personnel to higher priority operational tasks. Whenever SRAG personnel have the time, they work on integrating improvements. NOAA SEC has introduced a rapid prototyping process in an attempt to overcome the traditionally costly and drawn-out process of "transitioning" models to operational status. This entails subjecting scientific models and results to a linear process of validation and refinement; specifying and designing the user interface; developing mission-qualified software; and "backstepping" the process to make changes necessitated by problems with the science, the validation, or operational or customer requirements. The rapid prototyping process is a dynamic, circular process in which validation, user interfaces, customer products, and software testing are performed simultaneously in the user environment. It involves the scientists who originated the models, the forecasters and other users, and systems support staff working together to reduce the integration time from years to months and to cut costs, which can amount to millions of dollars, by more than 50 percent. The problem with the rapid prototyping process is that even it needs resources beyond the baseline operations staff. SEC has reallocated its limited resources to support the rapid prototyping staff, but the contingencies of day-to-day operations have hampered progress.

Figure 5.1 The number of environmental radiation models currently in operation that provide forecasting support to ISS (left column) falls short of the number of models required to provide reliable, accurate forecasts to ISS (right column). The shortfall exists for three types of forecast—forecasting the intensity and time of SPEs (top group), forecasting the area over the polar caps where SPE will reach the ISS (middle group), and forecasting the increase in radiation exposure on board ISS from growth of the trapped radiation belts associated with geomagnetic activity (bottom group).



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