Preemptive Scheduling of Equal-Length Jobs to Maximize Weighted   Throughput
  We study the problem of computing a preemptive schedule of equal-length jobs with given release times, deadlines and weights. Our goal is to maximize the weighted throughput, which is the total weight of completed jobs. In Graham's notation this problem is described as (1 | r_j;p_j=p;pmtn | sum w_j U_j). We provide an O(n^4)-time algorithm for this problem, improving the previous bound of O(n^{10}) by Baptiste. 
Philippe Baptiste, Marek Chrobak, Christoph Durr, Wojciech Jawor and   Nodari Vakhania