Forced off-time

On removal of the electric field, the ionic movement decreases dramatically and the initial alignment is recreated by elastic forces propagated from the surface boundary layers as well as by conduction. Therefore, switch-off times, /off, are an order of magnitude longer ( 20-100 ms) due to the high degree of disorder caused by the flow of liquid crystal and the absence of a restoring field effect. 

After the sample was taken, the sample port cover was replaced on its bolts but not bolted down as the procedure specified. The agitator was started and almost simultaneously the contents of the reactor erupted, forcing off the 6.8 kg sampling port cover. The analysis of resin samples from the reactor, erupted resin on the equipment and a sample taken from the reactor 15 minutes prior to the accident indicated that, during the time the technician was taking the reactor sample, the vessel contents were still reacting and essentially at the boiling point of the mass. 

Finally, it is possible to have a combination of PWM and PPM where one has variable width pulses and variable periods. In all cases, the output PWM stream is a series of pulses in which the dc voltage level is proportional to the ratio of the amount of on time with respect to the amount of off time for the pulses in the stream. Myopulse modulation, as implemented by Childress (1973) in his myoelectric controller, is an example of this form of pulse modulation (Fig. 32.25). This is an elegant proportional controller that can be implemented with a minimum of components. Because percentage myoelectric signal on time (EMG signal level above an arbitrary threshold) is monoton-ically related to muscle output force level, a proportional signal can be achieved very simply. This... 

Adjust the DP system to quickly response to the changes of the environment. The quick mode could be used in this circumstance to cope with the rapid speed and direction changes of the soliton. Thus, enough time could be obtained for the thrusts to resist the external force before the rig is being forced off. 

Typical recorded shear force versus time curves for a limestone powder are drawn in Fig. 4. The left curve illustrates the preshear stage without vibrations. The second curve shows the shear force during shear, without vibrations as well. The third curve depicts the shear force during vibrated shear for a new sample and the same consolidation and preshear conditions. The vibrations lead to a lower shear force maximum at the same normal stress level. Eventually, the fourth example shows also vibrated shear. But after the shear force maximum had been reached, the vibration excitation was switched off, marked by S in Fig. 4. After this switch-off the shear force increased again, nearly up to the unvibrated peak value. 

Fig. 10. Conformational flooding accelerates conformational transitions and makes them accessible for MD simulations. Top left snapshots of the protein backbone of BPTI during a 500 ps-MD simulation. Bottom left a projection of the conformational coordinates contributing most to the atomic motions shows that, on that MD time scale, the system remains in its initial configuration (CS 1). Top right Conformational flooding forces the system into new conformations after crossing high energy barriers (CS 2, CS 3,. . . ). Bottom right The projection visualizes the new conformations they remain stable, even when the applied flooding potentials (dashed contour lines) is switched off.

There are two main reasons why a pump should not operate below its MCSF (/) the radial force (radial thmst) is increased as a pump operates at reduced flow (44,45). Depending on the specific speed of a pump, this radial force can be as much as 10 times greater near the shut off, as compared to that near the BEP and (2) the low flow operation results in increased turbulence and internal flow separation from impeller blades. As a result, highly unstable axial and radical fluctuating forces take place. 

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