'I was facing a difficult problem.
As already noted, logical empiricism faced a difficult problem in distinguishing between genuine laws and accidental generalizations.
So it's time to reconsider whether the United States still faces a difficult problem with Mexican immigration.
TOKYO — When a South African mining company faced a difficult problem — how to get more black managers into leadership roles — it called on an unexpected source for help, a nonprofit group affiliated with a U.S. business school.
"The E.C.B. faced a difficult problem: it was setting a unique monetary policy for countries with very different monetary needs," Tano Santos, a professor of economics and finance at Columbia Business School, said.
Brush and small trees burned in most cases, but firefighters faced a difficult problem northeast of Los Angeles at the Lake Arrowhead resort, where a forest fire erupted early in the afternoon and added to the plume of smoke hanging over most of the region.
Developments of high-strength aluminum alloys have always faced a difficult problem: owing to their small size, the early-stage strengthening precipitates are difficult to characterize in terms of composition, structure and evolution.
Direct discovery of complex patterns from the audit trails faces a difficult problem of finding appropriate candidate patterns in a huge space of theoretically possible sequences of multisets of syntax trees and the values of parameters that determine a scope and periodicity of the patterns.
We face here a difficult problem: we have a complete weighted directed network featuring flows from stations to centers, and the goal is to extract some meaningful information.
In seeking answers, geologists are faced with a difficult problem.
That means their administrators are faced with a difficult problem: how to keep their budgets balanced as their two main sources of revenue stagnate or shrink.
