Platform doors will be installed at multiple stations in New York City’s subway system after a spate of attacks, including six stabbings, a top transportation official says. The pilot program will see the doors put into place at three stations, including the Times Square station, Metropolitan Transportation Authority Chairman Janno Lieber told NY1. Another effort focuses on using new technology, including lasers, to alert workers more quickly to when people get on tracks in the system, one of the largest in the world. Both pilot programs come after a “significant increase” in the number of people getting on the tracks and inside tunnels, Lieber said. “A lot of people are doing it voluntarily. Sometimes people with mental health issues do it and they don’t understand the dangers and so on,” he said. Others are being pushed. Michelle Alyssa Go, 40, was killed in January when a homeless man shoved her …