code: protected void convertToHours(LinkedList<TimephasedWork> list)
     {
        for (TimephasedWork assignment : list)
        {
           Duration totalWork = assignment.getTotalAmount();
           Duration workPerDay = assignment.getAmountPerDay();
           totalWork = Duration.getInstance(totalWork.getDuration() / 60, TimeUnit.HOURS);
           workPerDay = Duration.getInstance(workPerDay.getDuration() / 60, TimeUnit.HOURS);
           assignment.setTotalAmount(totalWork);
           assignment.setAmountPerDay(workPerDay);
        }
     }
docs: Converts assignment duration values from minutes to hours.
  
  @param list assignment data