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Random error 352 INDEX

In general, it is desired to make the pilot sequence as short as possible, however, very short pilot sequences lead to an inaccurate PDF estimation, and thus to incorrect estimations of Ar and r0nS(H. Fig. 19 shows the estimation performance for Lpii0t = 250,500,1000, and 2000. Fig. 19.(a) depicts 5at which describes the relative estimation error of Ar. For Lpoot = 2000, 8at decreases monotonically with increasing WNR, and is lower than 1% for WNR > —3 dB. Shorter pilot sequences lead to an increased relative estimation error. However, for some WNR, robust estimation is no longer possible at all. Lowering the WNR further introduces so much noise into the PDF estimation that the largest component of the computed DFT spectrum appears at any random frequency index 0 < l < Ldft — 1. [Pg.29]

If the error has even a small random component, the performance index (( ) will always reduce if automatic updating is implemented. The index measures only random error. If there was no random error then the index would have a value of 1 - no matter how large the... [Pg.209]

Many of the monitoring techniques suggested for inferentials can be applied to analysers. For example the performance index (0) can be used to identify excessive random error between analyser and laboratory. The CUSUM can be used to check for a bias error which can arise particularly if the analysis method does not exactly match the laboratory technique. [Pg.212]

Recall that the precision quantifies random errors. Let s consider the titration curve especially about the equivalence point (Fig. 10.1). It appears that the lower the slope is at the equivalence point, the higher the propagation of the error due to the pH measurement is. This is sufficient to justify the introduction of the parameter Ti to quantify the phenomenon, q is named the sharpness index. It is defined as being the magnitude of the slope of the titration curve ... [Pg.160]

Here 4 is the target state vector at time index k and Wg contains two random variables which describe the unknown process error, which is assumed to be a Gaussian random variable with expectation zero and covariance matrix Q. In addition to the target dynamic model, a measurement equation is needed to implement the Kalman filter. This measurement equation maps the state vector t. to the measurement domain. In the next section different measurement equations are considered to handle various types of association strategies. [Pg.305]

For a product where it is desired or necessary to show external predictability (e.g., to bridge to the commercial product for a low therapeutic index product), the external validation batch can be included in the same study as the IVIVC batches, normally in a separate study arm (i.e., not randomized). This reduces the probability of failing to fulfill the strict external validation criteria (prediction errors for Cmax and AUC of < 10%), as the data are collected in the same study population as those used to develop and validate the IVIVC. [Pg.302]

Figure 5. Stomatal density (SD A), epidermal cell density (ED B) and stomatal index (SI C) of sun and shade leaves from modem Nothofagus solandri trees at three localities on the South Island of New Zealand (Fig. 2 Horrible Bog (HOR), Kawatiri Junction (KJ) and St. Arnaud (SA). Nested mixed-model ANOVA of the entire data set indicate significant differences between sun and shade leaves for SD(p = 0.017) and ED (p = 0.011) but not SI (p = 0.108) Asterisks indicate significant ( p< 0.05) and highly significant ( p < 0.01) differences from nested mixed-model ANOVA in that character between the means of sun and shade leaves per location (Table 1). Five sun and five shade leaves per tree were measured (seven random counts per leaf). Error bars represent 1 S.E.M. Figure 5. Stomatal density (SD A), epidermal cell density (ED B) and stomatal index (SI C) of sun and shade leaves from modem Nothofagus solandri trees at three localities on the South Island of New Zealand (Fig. 2 Horrible Bog (HOR), Kawatiri Junction (KJ) and St. Arnaud (SA). Nested mixed-model ANOVA of the entire data set indicate significant differences between sun and shade leaves for SD(p = 0.017) and ED (p = 0.011) but not SI (p = 0.108) Asterisks indicate significant ( p< 0.05) and highly significant ( p < 0.01) differences from nested mixed-model ANOVA in that character between the means of sun and shade leaves per location (Table 1). Five sun and five shade leaves per tree were measured (seven random counts per leaf). Error bars represent 1 S.E.M.
Here, the catalytic activity is set as c, = i/k that is, the activity is monotonically increasing with the species index. Then, instead of global change to any molecular species by replication error, we modify the rule so that the change occurs only within a given range iu(error rate p, the molecule j + / with / a random number over [—i o, i o] is synthesized. [Pg.587]

NSGA-II parameters used in this study are maximum number of generations (up to 500), population size (100 chromosomes), probability of crossover (0.85), probability of mutation (0.05), distribution index for the simulated crossover operation (10), distribution index for the simulated mutation operation (20) and random seed (0.6). Except for the first and last parameter listed here, rest of the NSGA-II parameter values are taken from Tarafder et al. (2005). Values for maximum number of generations and random seed are obtained by trial and error. Our preliminary gene manipulation optimization runs show convergence within 500 generations for the random seed of 0.6. [Pg.412]

The selection of solvents and solvent blends for use in coatings and inks is based upon solubility/viscosity characteristics and application/performance properties. Published solubility parameters and hydrogen bonding indexes are used to construct two-dimensional solubility maps. Methodology is described, and illustrations are shown. Data are provided on evaporation times of neat solvents, viscosities and dry times of polymer solutions, electrostatic characteristics of solvents, and on selected solvent blend recommendations for several polymers. Unpublished test methods for flow testing and for substrate testing are provided. Combination of the results from these areas provides a viable method for practical solvent blend selection this approach is faster than random trial-and-error and can result in superior, formulated solvent blends. [Pg.121]

Figure 6.14 Deviation between the observed signal S and the expected signal St as a function of wavenumber index k for a triplicate measurement of one sample. Three repetitions of a measurement of the identical sample, in general, deliver three slightly different spectra. The differences can be categorised into random contributions (noise) and systematic effects (reproducibility error). The error contributions are evaluated around a wavenumber index k within a range from k — 6 to k + 6. Noise Ab,r(K) is estimated as the average over the standard deviations within each measurement while reproduction error b.rlK) is estimated as the standard deviation among the mean values of each of the three spectra within the given wavenumber index interval. Figure 6.14 Deviation between the observed signal S and the expected signal St as a function of wavenumber index k for a triplicate measurement of one sample. Three repetitions of a measurement of the identical sample, in general, deliver three slightly different spectra. The differences can be categorised into random contributions (noise) and systematic effects (reproducibility error). The error contributions are evaluated around a wavenumber index k within a range from k — 6 to k + 6. Noise Ab,r(K) is estimated as the average over the standard deviations within each measurement while reproduction error b.rlK) is estimated as the standard deviation among the mean values of each of the three spectra within the given wavenumber index interval.

See other pages where Random error 352 INDEX is mentioned: [Pg.246]    [Pg.185]    [Pg.14]    [Pg.75]    [Pg.501]    [Pg.142]    [Pg.73]    [Pg.108]    [Pg.150]    [Pg.346]    [Pg.127]    [Pg.219]    [Pg.281]    [Pg.53]    [Pg.258]    [Pg.1281]    [Pg.786]    [Pg.189]    [Pg.81]    [Pg.449]    [Pg.95]    [Pg.14]    [Pg.196]    [Pg.1376]    [Pg.337]    [Pg.1346]    [Pg.202]   


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