In the paper, a fuzzy variable structure control with a harmonizing mechanism has been developed and applied to the positioning control of an electro-hydraulic servo system. The simulation experiment results show that the performance by using the controller is better than those by just only using either fuzzy controller or variable structure controller. In addition, it also demonstrates that it...

Nowadays, hydropower plays an essential role in the energy market. Due to their fast response and regulation capacity, hydraulic turbines operate at off-design conditions with a high number of starts and stops. In this situation, dynamic loads and stresses over the structure are high, registering some failures over time, especially in the runner. Therefore, it is important to know the dynamic r...

More than 40 000 km year of water flows through the intricate hydraulic pathways inside leaves. This water not only sustains terrestrial productivity, but also constitutes nearly70%of terrestrial evapotranspiration, thereby influencing both global and local climate (Chapin et al. 2002). Thus, the central role played by leaf vascular systems in terrestrial biology provides an important context f...

In conjunction with association rules for data mining, the connections between testing indices and strong and weak association rules were determined, and new derivative rules were obtained by further reasoning. Association rules were used to analyze correlation and check consistency between indices. This study shows that the judgment obtained by weak association rules or non-association rules i...

A proportion-integration-differentiation (PID) controller is a generic control loop feedback mechanism widely used in multi-channel aircraft structural fatigue test. The PID parameter is obtained by test setup method in which PID is tuned after the test setup is actually performed, so that the tuning period becomes overlong. And the dynamic characteristic of mechanical and hydraulic equipment i...

The floodplains of many gravel-bed streams have a general stratigraphy that consists of a layer of topsoil covering gravel-dominated subsoil. Previous research has demonstrated that this stratigraphy can facilitate preferential groundwater flow through focused linear features, such as paleochannels, or gravelly regions within the vadose zone. These areas within the floodplain vadose zone may pr...