I reckon "dojicka" here is actually a pump. Please see the text below. Hope it will help you.
Power Plant Model
This applet provides a (very rough) simulation of a nuclear power plant. This power plant consists of three major components: the reactor, turbine, and condenser. Furthermore, there are three pumps, four valves, and one turbine. The reactor boils the water and the steam generated drives the turbine. After the turbine, the condenser cools the steam. In turn, external cooling water cools the condenser. The cooling pumps transport the water from the condenser tank back to the reactor tank.
The simulator calculates values for reactor-tank pressure, condenser-tank pressure, water levels, and so on, and displays them graphically. When components fail, the simulator calculates and displays the consequences for the running power-plant system. For instance, if a cooling pump fails and the corresponding valve is not closed, water may flow backwards from the reactor tank to the condenser tank. This process will then drain the reactor tank and expose the reactor core.