Modifying presets

One important case deserves special mention. In some spectrographs, notably the Philips Autrometer (9.7), the comparison of standard with unknown is done as follows. The time At required for a preset number of counts to be given by the standard is established. The unknown is then counted for the same interval. Time is measured with such high precision that this measurement does not contribute to the over-all error. But At for the standard is subject to the fluctuation defined by Equation 10-4. The result of the comparison is therefore subject to the counting error of Equation 10-14 if no background correction is made, or to a similar counting error that is modified to allow for the background correction. 

Typically, two solvents are prepared that are mixed in a controlled manner by the pumping system according to a preset gradient. The content of the organic modifier is increased linearly, stepwise, or exponentially in order to displace the sample. There is, therefore, the need for two solvent systems referred to as A (which is the aqueous component) and B (which contains the organic modifier HPLC grade, UV transparent). 

In its basic design, the equipment is similar to a 2-D TL glow-curve system as described previously, but with the addition of a modified Twyman-Green, Michelson type, interferometer between the oven and the photomultiplier. As the sample is heated, the TL signal is recorded while the movable mirror of the interferometer is scanning a given optical path difference in a preset number of steps. The interference pattern corresponding to each one-way scan... 

In the self-loading system the block or slide that moves backward and forward is stopped after each cycle and stays stopped until the trigger is pulled again. This mechanism can be modified so that the firearm continues to fire until either the ammunition is expended or the trigger released (automatic fire). Some firearms incorporate a selector lever, which allows them to deliver either a single shot or a burst of a preset number of shots, or to become fully automatic. 

The solution to this problem which is usually adopted in practice is to constrain particular parameters to preset values, usually zero, in a least-squares fit of the Hamiltonian to the data. This has the effect of modifying the values obtained for the other parameters in the Hamiltonian. In order to interpret the results in this situation, it is necessary to subject the effective Hamiltonian to yet another transformation to bring it into the form which is actually used in the empirical fit. Before we do this, however, let us consider a particular example to help us understand the nature of these indeterminacies. There is a well-known indeterminacy between the parameters ynv and Ain the Hamiltonian for a molecule in a 2U state, first pointed out by Veseth [33], If we confine ourselves to the simple Hamiltonian... 

There are adaptive PCs. They are control system that changes the settings in response to changes in machine performance to bring the product back into its preset requirements or specification. The shift is maintained so that the control has adapted to changing conditions. It is a technique typically used to modify a closed loop control system. The process control comparator is the portion of the control elements that determines the feedback error on which a controller acts. 

Composites with preset curing rates and temperature, suitable physical and mechanical performance, and high optical properties can be obtained by modifying the type and ratio of the... 

In the static addition mode, a preset volume of modifier highly dependent on sample size is directly added to the sample, held in the cell, prior to extraction. The principal disadvantage of this mode is that, as the supercritical fluid begins to circulate through the sample, the modifier is swept from the extraction cell, so the matrix is brought out of contact with the modified supercritical fluid. Although dynamic addition is usually more effective than static addition — the modifier is continuously passed through the sample in the former — Ashraf and Taylor [35,36] found the static addition of methanol... 

This modified covariance matrix is compared with the preceding one. If the difference is smaller than a preset threshold, the computation is terminated or else return to step 2a, and a new cycling is invoked by using the estimated principal component directions as initial guesses, together with the untouched original data matrix X. 

Once a column has been chosen, the two variables which can be modified to optimise the separation of components are temperature and carrier gas flow-rate. The latter is often preset although the newer microcomputer controlled instruments allow the flow rate and temperature to be changed between runs for automatic optimisation. Accurate control of column temperature is important in order to obtain reproducible chromatograms. 

To modify one of your own presets, select it from the list, modify the parameters in the dialog box, and then click the Save button. 

The top waveform is the original loop file and the bottom is the same waveform modified by the Amplitude Modulation plug-in, using the Wacky preset. 

The Reverberation mode list is another set of presets that alter many background characteristics of the effect. None of the parameters that are modified by the selections on this list is available for manual adjustment in the plug-in window. The Preset list at the top of the window is a good place to start exploring this and many of the other settings in this complex and important effect. 

The Preset list and Room type lists work together to set the overall operation of the effect. Select a Preset first and then a Room type to modify it. As with the XFX Reverb plug-in, tbe Room type sets internal parameters that cannot be adjusted by the user. 

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