@Test
 public void testAdd() {
   RegulationAccumulator rc = new RegulationAccumulator(1.0, -2.0);
   RegulationAccumulator rc1 = new RegulationAccumulator(2.0, -3.0);
   rc.add(rc1);
   assertEquals("correct up-regulation", 3.0, rc.getUpRegulationCapacity(), 1e-6);
   assertEquals("correct down-regulation", -5.0, rc.getDownRegulationCapacity(), 1e-6);
 }