жесткий is Russian for "intense"

Millions of passengers traveling through Russia soon will have to take a lie detector test as part of new airport security measures that could eventually be applied throughout the country.
    The technology, to be introduced at Moscow's Domodedovo airport as early as July, is intended to identify terrorists and drugs smugglers. But many passengers will be chilled by the set of four questions they will have to answer into a machine, including, "Have you ever lied to the authorities?"
    The machine asks four questions: The first is for full identity; the second, unnerving in its Soviet-style abruptness, demands: "Have you ever lied to the authorities?" It then asks whether either weapons or narcotics are being carried.
    To cut delays, passengers will take the tests after taking off their shoes and putting baggage through the X-ray machines. He doesn't get his shoes back until he satisfactorily answers the questions. Each test will take up to a minute. "If a person fails to pass the test, he is accompanied by a special guard to a cubicle where he is asked questions in a more intense atmosphere," says Vladimir Kornilov, IT director for the airport.
    The fully automated instrument to be used, known as the "Truth Verifier," is hardly the polygraph familiar from old spy thrillers. Passengers will simply speak into a handset. Thanks to "layered-voice-analysis technology," the system, developed by an Israeli company, can even establish whether answers come from the memory or the imagination.

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