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Incomplete data

At this point, analysts have a set of adjusted measurements that may better represent the unit operation. These will ultimately be used to identify faults, develop a model, or estimate parameters. This automatic reconciliation is not a panacea. Incomplete data sets, unknown uncertainties and incorrec t constraints all compromise the accuracy of the adjustments. Consequently, preliminary adjustments by hand are still recommended. Even when automatic adjustments appear to be correct, the resiilts must be viewed with some skepticism. [Pg.2569]

Estimate the effective fraction w etted packing area by Figure 9-46 or 9-43. As a general rule, try not to accept design if fraction wetted is le.ss than 0.5. If it is less, adjust tower conditions to raise value, bearing in mind that this factor is based on scattered and very incomplete data. [Pg.361]

Manufacturers and specialist materials development associations publish extensive corrosion data in the form of monographs, and this form of presentation is also used in national standards. The most recent comprehensive text in this category is perhaps the publication by the Zinc Development Association . The work is important in that the section on chemicals also deals with common, though complex, chemical formulations, e.g. Are-extinguisher fluids, soaps and syndets, agricultural chemicals such as pesticides and fertilisers. This publication also demonstrates the mammoth task of recording all the available data for just one material. A comparable book for mild steel would probably be much larger, whereas for many other materials the information has not yet been determined. Thus at best, only very incomplete data are available in this form. [Pg.406]

Effective use of incomplete data sets Rapid analysis of data... [Pg.693]

In Table 3.2 the preparative precoated silica gel plates for straight phase PLC from different mamrfacturers are summarized. Incomplete data are due to incomplete information received from the manufacturers. [Pg.43]

Overall, each of these KBS approaches has its place, depending on the needs of the problem and the characteristics of the process. However, the advantages, limitations, and roles of the various methods must be clarified so that problem-solving efficiency can be achieved along with the ability to reach correct conclusions despite challenging circumstances knowledge that is incomplete data that are incomplete, unreliable, or extremely plentiful or situations that are untested or completely unanticipated. [Pg.71]

Completion of missing data. The proceeding of completion depends on the character of the incomplete data set. In conventional data lists of random character such as a nxm data list (data matrix) which contain results of several analytes (m) in diverse samples (n), missing data are frequently substituted by the mean of the respective analyte over all the samples. [Pg.247]

Association Retrieving a complete copy of a data item if only incomplete data can be fed in. [Pg.89]

Resource estimates and current production Natural gas from coal is present wherever coal is found and, as coal is found in great quantities throughout the world (see Section 3.5), natural gas from coal may represent a large energy source. As for all types of unconventional gas, the published reserve and resource figures show great variations and are often based on estimations from incomplete data. In addition, as... [Pg.94]

The thermodynamic theory of solutions is complete in the sense that the exact relations among thermodynamic coefficients are all known, the Gibbs-Helmholtz equation for example. However in practice it commonly is necessary to make predictions on the basis of incomplete data, therefore to make extrapolations and other approximations. Reliable approximations depend upon a knowledge of the solution structure. [Pg.548]

Checking the data quality is strongly recommended inspection of the Wilson plot and data reduction statistics is very useful in judging the extent of the resolution to which the data can realistically be used. Pathologically bad data, for example those from a split crystal, twinned data, systematically incomplete data, low resolution overloads will always make model building and refinement hard if not impossible. [Pg.167]

A Bayesian hierarchical modeling framework was used to evaluate the effects data for each species and test endpoint (Figure 7.4). Hierarchical models reduce the effect of incomplete data sets, small numbers of tests, inconsistent information on effects among species, and other issues that lend uncertainty to the risk characterization results. [Pg.134]

An empirical structure-property relation is based on observations in a set of fragmentary and incomplete data, instead of being based on a well-established theory of wide applicability and tested extensively. It is a tentative hypothesis designed to explain... [Pg.202]

Reproductive risk descriptors are intended to address variability of risk within the population and the overall adverse impact on the population. In particular, differences between high-end and central tendency estimates reflect variability in the population but not the scientific uncertainty inherent in the risk estimates. There is uncertainty in all estimates of risk, including reproductive risk. These uncertainties can result from measurement uncertainties, modelling uncertainties and assumptions made due to incomplete data. Risk assessments should address the impact of each of these uncertainties on confidence in the estimated reproductive risk values. [Pg.136]

Only one structure (99) based on X-ray crystallography has been reported, with incomplete data. Angles are in degrees, and bond lengths in A.132... [Pg.27]

Note Some original target compounds (see Table I) are not included because of inconsistent or incomplete data. a All rejections indicated by greater than (>) were obtained by using the analytical limit of rejection in eq 1. Actual rejection may approach 1002. — means cannot be determined from available data neg means negative value. [Pg.439]

Note Some original target compounds (see Table I) are not included because of inconsistent or incomplete data. [Pg.440]


See other pages where Incomplete data is mentioned: [Pg.571]    [Pg.2179]    [Pg.355]    [Pg.230]    [Pg.66]    [Pg.415]    [Pg.421]    [Pg.532]    [Pg.26]    [Pg.163]    [Pg.164]    [Pg.91]    [Pg.268]    [Pg.44]    [Pg.144]    [Pg.279]    [Pg.39]    [Pg.551]    [Pg.678]    [Pg.264]    [Pg.229]    [Pg.21]    [Pg.31]    [Pg.123]    [Pg.131]    [Pg.717]    [Pg.498]    [Pg.138]   
See also in sourсe #XX -- [ Pg.284 , Pg.285 ]

See also in sourсe #XX -- [ Pg.261 , Pg.323 ]




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Calculations for Missing and Incomplete Data

Incomplete

Incomplete or Insufficient Data Sets

Incompleteness

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