System optimization. Beyond monitoring how machinery, assets, and workers are performing, companies are using IoT applications to run complex systems, often through closed-loop systems that can automatically make decisions based on sensing input. Smart grids for electricity, water,and transportation networks are cropping up around the world. In these systems, sensors pick up performance data and actuators are used to take appropriate action—such as coordinating traffic signals based on the number and movement of vehicles in a city. In Mannheim, Germany, for example, the electric utility is using smart grid technology to confirm whether repairs have been made effectively, helping improve system performance.