Â­TÂ­here are many different ways to create a motion sensor. For example: 1  It is common for stores to have a beam of light crossing the room near the door, and a photosensor on the other side of the Â­room. 2  When a customer breaks the beam, the photosensor detects the change in the amount of light and rings a bell.
Definition of weir. 1  1 : a fence or enclosure set in a waterway for taking fish. 2  2 : a dam in a stream or river to raise the water level or divert its flow.
Some of the major important types of wastewater treatment process are as follows: 1. Effluent Treatment Plants (ETP) 2. Sewage Treatment Plants (STP) 3. Common and Combined Effluent Treatment Plants (CETP). It is estimated that every year 1.8 million people die due to suffering from waterborne diseases.