You are tasked to design a system that will monitor and regulate the air flow in a hospital ward. The design should take inputs from all of the following four sensors:
Sensor A has been set to trigger when the windows in the ward are open.
Sensor B has been set to trigger when the relative level of moisture in the air has exceeded 30%.
Sensor C is an anemometer and has been set to trigger when the rate of air flow at the ventilation grills has dropped below 20 m/s.
Sensor D is a thermometer and has been set to trigger when the ambient temperature in the ward has exceeded 20°C.
The system should operate based on the following conditions:
• If the windows in the ward are closed, the system should switch on the air conditioning unit automatically if 1) the temperature is over 20°C and airflow rate is less 20m/s, or 2) temperature is over 20°C and humidity over 30%.
• If the windows in the ward are open and the ambient temperature is over 20°C, the system should generate an alert.
a) Based on the information given above, provide a Truth Table for the system. For both the air conditioning unit and the alert system, use a Karnaugh Map to obtain a Boolean Expression for each case.