How does your smile rate on a scale of zero to 100? If you worked for Japan's Keihin Electric Express Railway Co., you'd know—on a daily basis.

The Tokyo-based train company is using a "Smile Scan" system to evaluate the grins of its 530 station staffers at 15 stations when they report to work each day, Japan's Mainichi Daily News reported earlier this month. The smiles (including eye movements, lip curves and wrinkles) are scored on a scale ranging from zero (scowling) to 100 (glowing) using a camera and computer provided by Kyoto-based Omron Corp., with low scores earning employees automatically generated advice such as, "You still look too serious," or "Lift up your mouth corners."

The railway network covers 87 kilometers and serves an average of 1.2 million passengers daily. The idea is for workers to print out and carry around an image of their best smile in an attempt to remember and replicate it as they encounter customers throughout their shifts.

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