Power average

The quantities in this fomuila are defined as in equation Bl.5,32. but with the laser parameters translated into more convenient tenns is the average power at the indicated frequency is the laser pulse duration ... 

The most connnon commercially prepared amplifier systems are pumped by frequency-doubled Nd-YAG or Nd-YLF lasers at a 1-5 kHz repetition rate a continuously pumped amplifier that operates typically in the 250 kHz regime has been described and implemented connnercially [40]. The average power of all of the connnonly used types of Ti-sapphire amplifier systems approaches 1 W, so the energy per pulse required for an experiment effectively detennines the repetition rate. 

Power source Initial average power, W Spacecraft Mission type Launch date Orbital lifetime, yr... 

In terms of strietly passive reaetive loads, the power faetor is the resulting phase between the voltage and the eurrent waveforms. In power supplies though, it is the distortion to the voltage waveform resulting from the time whieh input reetifiers eonduet. Power faetor is measured from 0 to I where I is where all the power is used by the load (purely resistive). The typieal eapaeitive input filter found in power supplies has an average power faetor of 0.5 to 0.7. 

Power factor adjustment Although related to the average power factor of the load, the method of calculation may be based directly on measured power factor or on the measurement of reactive kVA over the period. Values at which power factor charges are incurred vary from 0.8 to 0.95 lag. 

Sometimes power loss and heat generation occur intermittently and to find the average amount of heat that will go into the oil, the average power loss should be calculated. Usually, taking an average over a 1-hour period should be sufficient. Therefore, hydraulic systems should include a positive means of heat removal. Normally, a heat exchanger is used for this purpose. 

Notice that those distribution functions that satisfy Eq. (4-179) still constitute a convex set, so that optimization of the E,R curve is still straightforward by numerical methods. It is to be observed that the choice of an F(x) satisfying a constraint such as Eq. (4-179) defines an ensemble of codes the individual codes in the ensemble will not necessarily satisfy the constraint. This is unimportant practically since each digit of each code word is chosen independently over the ensemble thus it is most unlikely that the average power of a code will differ drastically from the average power of the ensemble. It is possible to combine the central limit theorem and the techniques used in the last two paragraphs of Section 4.7 to show that a code exists for which each code word satisfies... 

An average power constraint on the input distribution will be assumed of the form,... 

W.m (see Ch.l4). To get enough return flux at the minimum laser power, one needs to optimize the laser specifications (continuous wave or pulsed, pulse width, pulse repetition rate, (average) power, spectral profile) taking into both saturation, technological, budget and operation constraints. This is the challenge described in detail in the above mentioned chapter. 

Experiments on the sky. Two experiments have been carried out at the sky, using two laser installations built for the American and French programmes for Uranium isotope separation, respectively AVLIS at the Lawrence Livermore Nat l Lab (California) in 1996 and SILVA at CEA/Pierrelatte (Southern France) in 1999. The average power was high pa 2 x 175 W, with a pulse repetition rate of 12.9 and 4.3 kHz, a pulse width of 40 ns and a spectral width of 1 and 3 GHz. Polarization was linear. The return flux was < 5 10 photons/m /s (Foy et al., 2000). Thus incoherent two-photon resonant absorption works, with a behavior consistent with models. But we do need lower powers at observatories ... 

During the black incorporation phase, the aftermixing phase, the second part of the remilling phase and the second part of the final batch mixing phase, an average power consumption has been taken... 

The ratio between average power and enthalpy increase per unit of time is compared between the various mixing phases. 

As in boundary-layer flows, smaller reference floe diameters are found with gas sparging than with the same average power input in a baffled stirred tank 127] or [44,45]. This can be explained if it is assumed that the floes come into close contact with the gas phase and find their way into the zones of higher stress. 

It can be seen that for the same average power input, greater stresses are produced by gas sparging than by many impellers. Fig. 17. According to the comparison in Fig. 17, evidently zones exist in bubble columns in which the energy densities are 20 times higher than in a stirred tank. But the comparison on the basis of average power input in Fig. 16 shows that also impeller (for example small inclined blade impellers) exist which produce more shear than bubble columns. 

Viscosimeters at higher average power input only cause stresses of the same order as that produced by low-shear impellers (Fig. 16). 

The results in Fig. 25 for hybridoma cells show that due to the low growth rate, which lies in the range of p < 0.02/h, animal cells could only be cultivated under very moderate stress conditions of it< 0.005 -0.05 N/m. That means that, also for very low-shear impellers such as large-blade impellers, the average power input has to be limited to P/V <30-50 W/m ... 

A considerable decrease both in the deposition rate and in powder formation was found when the 13.56-MHz excitation was modulated with a square wave of 2 Hz [510, 511]. In the y -regime, Biebericher et al. [512] have observed a decrease in deposition rate from 1.0 nm/s in a continuous-wave (cw) 50-MHz SiH4-H2 plasma, to 0.2 nm/s in a similar (i.e. with the same average power of 10 W) plasma, modulated by a frequency of 100 kHz. 

Here, results are shown from experiments performed in ASTER, reported by Biebericher et al. [512. 519], A SiH4-H2 (50 50 flow ratio, total flow 60 seem) plasma was generated at an RF excitation frequency of 50 MHz. The substrate temperature was 250°C. The RF signal was ampitude modulated (AM) by a square wave. The modulation frequency has been varied in a range of 1-400 kHz. The modulation depth was always 90%. The duty cycle was fixed at 50%. The pressure amounted to 0.2 mbar, and the average power was kept at 10 W. With a duty cycle of 50%, this leads to a power of 20 W during the plasma-on period. 

Table 8E-4 gives the information needed to specify the pumps for the plant and the average power required to operate them. A detailed calculation for the barge unloading pump follows. 

A pump efficiency of 80% is obtained from Figure 8-5. This gives a brake horsepower (BHP) of 37.50. A motor efficiency of 89% is obtained from Figure 8-6. The average power per day used by these pumps is ... 

The warehouses are designed to be operated only 35 hours per week and the outside lights should only be on about half the time. The other power will be on most of the time. This gives an average power of 67 kw. 

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