Fixed errors

Typically, fixing errors and redesign account for around 30% of product development time, as shown in Figure 5.3, and improving this position provides an opportunity for lead time reduction. This means doing more work early in the process when (Parker, 1997) ... 

Consider now a situation in which the bias limits in the temperature measurements are uncorrelated and are estimated as 0.5 °C, and the bias limit on the specific heat value is 0.5%. The estimated bias error of the mass flow meter system is specified as 0.25% of reading from 10 to 90% of full scale. According to the manufacturer, this is a fixed error estimate (it cannot be reduced by taking the average of multiple readings and is, thus, a true bias error), and B is taken as 0.0025 times the value of m. For AT = 20 °C, Eq. (2.9) gives ... 

Most controllers are calibrated in minutes (or minutes/repeat, a term that comes from the test of putting into the controller a fixed error and seeing how long it takes the integral action to ramp up the controller output to produce the same change that a proportional controller would make when its gain is 1 the integral repeats the action of the proportional controller). 

Up to 50% of maintenance effort is spent fixing errors that have been present since the initial phase of the development. 

Life-Cycle Phase Systems Systems Systems Systems Capability Fix Error... 

This eirgument implies that as the gap thickness h decreases with fixed error in the gap, the boundary to region III should shift upward in proportion to h. This seems to agree with the experiments. If this argument is correct, then from the concentration-dependence of this boundary one can infer the concentration-dependence of 5 it must then scale as 5 a 0. ... 

There may be certain fixed errors, also called systematic errors, which cause repeated measurements to be in error by approximately the same amount. For example, if an instrument is incorrectly calibrated, then every measurement may be off by approximately the same amount. Other examples of systematic errors include different experimenters taking measurements differently or some change to the environment such as a valve leaking or left open that should have been closed. 

There are some measurement techniques that have an inherent error in the measured value compared to the actual value. This is sometimes called a fixed error, although this is somewhat of a misnomer as the amount of the error usually varies with the reading. An example of this type of error is using a thermocouple inserted through the wall of a furnace to measure the gas temperature inside the furnace. This produces a reading... 

D. P. Dolata and J. Arnold, /. Mol. Graphics, 10, 222 (1992). An Easily Fixed Error in the Nyburg Algorithm for Discovering the Best Fit Between Molecules. 

When stripping current is varied, stripping curves are shifted because ohmic drop and electrode polarisation vary with current density. Thus if the cut-off voltage is fixed, errors will be introduced depending on the steepness of the transition. Electrode polarisation can indeed become important as exchange current between 0.6 and 7.8 mA/cm with a 200 mV tension variation per decade of current has been measured (35) for the Ag-Agi Rbl interface. 

The goal of TQM and QC is the reduction of errors to the absolute minimum, leaving only small random errors that can be addressed with the statistics discussed in Chapter 2. To fix errors, they must first be found and diagnosed. An overview of the different sources that contribute to analytic errors is shown in Figure 3.17. Errors associated with the matrix cannot be controlled, but they can be taken into account. 

Fixed error in the system could arise from two sources First, the dewar volume in the cylindrical test section was known with an accuracy of only 0.1 by water calibration at room temperature second, the thermocouple spacing measurement was accurate to only )i6-in. Percentage error in the volumetric measurements was, therefore, afunctionof the total change of liquid level for any given test and varied from 0.4 at the high flow rates to 1.4 at the lower values. 

In this mode of control, the value of the output P depends on the history of errors from when observation started at t= 0. For a fixed error, the different Kj values produce different values of P as a function of time. Faster rates provided by larger values of thus cause a much greater controller output at a particular time after the error is generated. The relationship between the output values and the error for two different values of Kj is illustrated in Fig. 7.8. 

Measurements are shown to comply with the fixed error-threshold ... 

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