Active control is a research area that focuses on developing methods to actively manipulate and control the behavior of physical systems. This can include a wide range of applications such as controlling vibrations in structures, noise reduction in vehicles, and stabilization of unstable systems. Active control typically involves the use of sensors to measure the behavior of the system, a control algorithm to process this information, and actuators to apply the necessary control inputs to achieve the desired response. Researchers in this area work on developing innovative control strategies and technologies to improve the performance, efficiency, and safety of various systems.