The experiments have shown that the reasons of this kind of damage are low-frequency self-excited oscillation as well as external vibration coupled with acoustic resonance of the vessel with an attached the pipe leading to fleeting reduction of drag force in the valve and to high-frequency valve chatter.
CONCLUSIONS: Hospital procedural volume was associated with higher frequency of valve repair, higher frequency of prosthetic valve usage in elderly patients, and lower adjusted operative mortality.
This improvement is achieved mainly by the reduction of frequency of valve operation, like MS dryers requiring periodical regeneration, and by the standardized module arrangement of the DS with SC.
It was found that use of oscillatory air supply with a proper frequency and valve on/off time ratio to replace steady air supply would increase not only the collection zone recovery but also the froth zone recovery.
While the two sensitivity indexes of the natural frequency of servo valve, the damping ratio of servo valve, the system supply oil pressure, the internal leakage coefficient, the effective piston area of servo cylinder, the proportional gain, the force sensor gain and the viscous damping coefficient are large.
While the two sensitivity indexes of the natural frequency of servo valve, the damping ratio of servo valve, the system supply oil pressure, the internal leakage coefficient, the effective piston area of servo cylinder, the proportional gain, the force sensor gain and the viscous damping coefficient are large. .
Second, two strategies to equalise and optimise the workload (conduction ratio and switching frequency) of each valve are developed: 1) the circular queue schedule strategy ensures uniform workload of each valve and 2) the circular queue with random rotation schedule strategy can further decrease the switching frequency drastically by introducing randomness.
The resonance frequency increases as valve flap thickness increases and width decreases.
Over time, with more force and frequency added, the valve sees the same force, the same opening and closing, that it's going to see in the body after implementation".
An optimal synchronization between the high voltage (HV) pulse frequency and solenoid valve frequency has been determined, allowing for the prevention of electrical breakdown events within the inter-electrode gap over a negative voltage ranging from 0 to 4.5 kV.
