What is the fine-grained topic of the following text: By incorporating the oscillating piston method, which is an industry-proven sensor technology, the ViscoPro 2100 Online Viscosity Monitoring System is the best choice for applications requiring fast, real-time analysis with reliable data that correlates tightly with laboratory results. Only return the topic.
ViscoPro 2100 Online Viscosity Monitoring System's use of the oscillating piston method