Evaluation precision

As already mentioned in the introduction, ruggedness is a part of the precision evaluation. Precision is a measure for random errors. Random errors cause imprecise measurements. Another kind of errors that can occur are systematic errors. They cause inaccurate results and are measured in terms of bias. The total error is defined as the sum of the systematic and random errors. 

The basic criterion for successful validation was that a method should come within 25% of the "true value" at the 95% confidence level. To meet this criterion, the protocol for experimental testing and method validation was established with a firm statistical basis. A statistical protocol provided methods of data analysis that allowed the accuracy criterion to be evaluated with statistical parameters estimated from the laboratory test data. It also gave a means to evaluate precision and bias, independently and in combination, to determine the accuracy of sampling and analytical methods. The substances studied in the second phase of the study are summarized in Table I. 

ISO TR 9272, 2005. Rubber and Rubber Products - Evaluating precision for test methods. 

ASTM D4483, 2003. Standard practice for evaluating precision for test method standards in the rubber and carbon black industries. 

If we were to differentiate this expression with respect to T and V, we would be able to evaluate precisely the rate at which p varied with respect to T (a constant) for any given T, or, with respect to V, for any given V (a variable) (see Problem 4.13). 

Apart from the extraction and analytical methods, it is fundamental that the quality of analytical data is demonstrated by running quality controls (QC). De Vivo et al. (2004) recommend to validate analytical data by evaluating precision (which expresses the extent of reproducibility of analytical determinations) and accuracy (which expresses the degree of correctness of the data compared with true values) of results through the use of standard samples analysed together with the samples collected during the mapping activities. The accuracy and precision so determined should not exceed 15% for the analytical results to be considered acceptable. 

Some coefficients of and A 0 have been evaluated precisely in terms of a series expansion in powers of x and/or y [26,27]. 

Adsorption using different probe molecules is available for determination of the pore entrance structure. N2 molecules adsorbed near the pore entrance at 77 K often block further adsorption, indicating the presence of ultramicropores and pore-neck structures. The preadsorption technique is also effective for elucidation of the pore entrance structure. Fractal analysis using adsorption is helpful to understand the fine structure of nanopore walls. [10,11] However, the probe molecules must be carefully chosen and the monolayer capacity must be evaluated precisely, because the BET monolayer should not be used. 

Some coefficients of and have been evaluated precisely in terms of a... 

The voltammetry for the ion transfer at the interface of two immiscible electrolyte solutions, VITIES, is expected to offer much information available for analyzing the ion transfer at the aqueous/membrane interface [14,15], if the organic solution is regarded as the membrane. Transfer energies of ions at the aqueous/membrane interface and amounts of ions transferred can be evaluated precisely by VITIES. The kinetics of the ion transfer and the interfacial adsorption can also be investigated by this method. The present authors measured the relations between the membrane potential and the membrane current (the... 

The acid strength of a given acid site is equal to the value of pKgg+ or pKp of the less basic indicator which changes colour upon reaction with the centre. It is assumed that for such indicators the ratio of [BH ]/[B] or [R ]/[R0H] is equal to unity, The colour change of the indicator may be followed visually or by spectroscopy. In the latter case the acid strength may be evaluated precisely for any catalyst even a coloured one. 

The purpose of all of these techniques is to determine how a system performs based on the selection of one or more performance parameters. The first two techniques on repetitive measurement and the use of internal test or reference samples is the classical way to evaluate precision. However this can be a time consuming process if it is not carefully planned, and quality assessment frequently provides a way to minimize the number of measurements. The use of duplicate samples in routine testing, and the accumulation of this information over a time period, is another approach to evaluating precision. More details on this will be given in Section 8 on laboratory precision, which addresses both intralaboratory and interlaboratory operations. 

Hence, the stated above similar techniques allow one to determine the fractal dimension of a macromolecular coil in a good solvent on the basis of the known molecular characteristics of polymer. These teehniques give identical results, but evaluation precision with two characteristics (C and S) is somewhat higher, than at one (CJ usage. 

Whenever, the thermodynamic Debye temperature for polymers exceeds their condensed-state temperature. Therefore the quantum statistics of atomic vibrations should be taken into account. As the F (6/T) function has no a precise analytical form, the true activation parameters cannot be evaluated precisely. Nevertheless, in the Tb < T < range, only two vibrational modes, those with the Vt and Vb frequencies, are shown to give the greatest contributions in... 

A. Piratelli-Filho, F.H. Tavares Fernandes, R. Valdes Arencibia, Application of Virtual Spheres Plate for AACMMs evaluation. Precision Engineering, 32-2 (2012) 349-355. 

For mixtures of several nucleotides and/or nucleosides, however, spectroscopic analyses become difficult because UV spectra contain only a small number of absorption bands and have a very similar shape. In these cases, it is necessary to evaluate precisely and in detail the minor differences in the spectra, such as the position of the shoulders and the relative intensities of the various bands, which are often sufficient for multicomponent analysis. Two approaches, the so-called principal component regression (PGR) and partial least-squares (PLS) regression analyses, with Fourier preprocessing of UV spectra, have been developed. These methods can monitor continuously entire spectral regions, and they are generally reliable and accmate. They have allowed the composition of 14 unknown mixtures of dAMP, dCMP, dGMP, and dTMP to be analyzed, with average per cent errors of 0.60-1.85%. The presence of a protein... 

For nonionic dyes, their surface interactions, such as ion-dipole and hydrogen bonding, can significantly alter the photophysical and photochemical properties of the dyes. On the other hand, organically modified clays accommodate a variety of nonionic dyes without significant modification of their properties. While the amounts of dye intercalated cannot be controlled (or evaluated) precisely, the photoprocesses of such dyes can yield important microscopic information. Hierarchical control from micro- to macroscopic structures is a key issue for the practical application of intercalation compounds. Recent developments regarding controlled macroscopic forms of intercalation compounds, such as particle shape (300,301), and the characterization of suspensions (302) represent milestones for the application of intercalation compounds. 

Asakai et al. [22] implemented coulometric titration on potassium dichromate (K2Cr207), an essential reference material for volumetric analysis. Its reliability and certainty was evaluated precisely and automatically titrating with Fe. In Fig. 7 [22], the coulometric titratimi cell was schematically illustrated. The counter electrode was isolated from the analytical solution preventing cross-reacting from the electrolysis products and the analyte. The oxidimetric purity of K2Ct207 was obtained on the basis of Faraday s law. Furthermore, the dependences of the purity on sample mass and applied electrolysis current were investigated. 

The prescribed GC—FIB testing method has an evaluated precision of <1% relative standard deviation to determine D-lactic acid in PLA. 

It is difficult to evaluate precisely the human response caused by an acute, hazardous exposure for a variety of reasons. First, humans experience a wide range of acute adverse health effects, including irritation, narcosis, asphyxiation, sensitization, blindness, organ system damage, and death. In addition, the severity of many of these efifects varies with intensity and duration of exposure. For example, exposure to a substance at an intensity that is sufficient to cause only... 

By the observation of quantum beat Q, one can determine the details on the nuclear levels, from which the hyperfine interaction parameters are evaluated precisely. 

Evaluates precision, accuracy, linearity range, LOD, LOQ, specificity, ruggedness and robustness in pre-validation experiments. 

Poisson s ratios in crystalline polymers were evaluated precisely from direct measurements of the sample dimensions during deformation over a wide range of extensional speeds, strain rates, temperatures and the degrees of crystallinities of the samples. True stress-strain curves with inhomogeneous deformation could be determined using the transient Poisson s ratio data in the necked portion and unnecked portions. Mechanical nonlinearity is closely related to the nonlinear behavior of Poisson s ratio in each region. We will now describe our conclusions for each region in more detail. 

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