Researchers say predicting future water usage for drilling is tough, citing economic and technological uncertainties.

These newsroom crises have come when the Times can least afford them-during a period of technological and economic uncertainty that has affected the entire industry.

These are activities which form part of a project but do not directly contribute to the resolution of the scientific or technological uncertainty.

When achieving design objectives requires the resolution of scientific or technological uncertainty within a project, work to do this will be R&D.

Design activities which do not directly contribute to the resolution of scientific or technological uncertainty within a project are not R&D.

This equality also applies to the methods used to resolve scientific or technological uncertainty.

Because there is scientific and technological uncertainty around whether a material with the desired physical characteristics can be made, the R&D continues.

The scientific or technological uncertainty associated with this work is resolved once prototype plugs have been fully tested in the engine.

Technical problems that have been overcome in previous projects on similar systems are not likely to be technological uncertainties.

In either case, a valid technological uncertainty can still exist.