Friday was the one-year anniversary of a frightening day of violence at South Philadelphia High School. That’s when more than a dozen Asian immigrant students were attacked by their African American peers. The victims said the attacks were racially motivated.A year later, those same students say things have improved. Last year’s attacks touched off an eight-day boycott by students protesting a lack of safety at the school. Friday, the students held a rally. They tied blue ribbons symbolizing peace to the school gates. Senior Duong-nghe Ly said the new principal — Otis Hackney — has made a difference. “Mr. Hackney has been very responsible … to try to make the school better,” he said. “And I really feel safer in the school right now.”After-school program director Latoria Anderson agreed. “The school’s climate has changed tremendously, the students are friendlier to one another, the staff is more involved with the students,” she said. “It’s just a dramatic change all over.”Anderson said the stepped-up security, along with more programs for the students, has helped foster a more positive atmosphere at the school.