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Logarithmic model

Show that for a given order of polynomial the maximum relative error of the vapor pressure is considerable lower for the logarithmized model. [Pg.209]

In diis section, we will discuss exponential and logarithmic models and their basic characteristics. [Pg.546]

Adams (1987) has stated a similar relation between fatalities (F) and vehicle kilometres (V), which was presented Log (F/V) = a + b y where y = year - 1985. Broughton (1988) has tested this logarithmic model on data from Britain between 1950 and 1985 and the results fitted well. In the same study Broughton applied the same model to data from four western countries U.S.A (1943-85), West Germany (1965-85), Norway (1947-85) and New Zealand (1948-83). He found that this model describes the data pretty well. [Pg.35]

The dissolution kinetics of titanium follows a two-phase logarithmic model (Healy and Ducheyne, 1992, 1993). In the first phase the concentration of OH groups increases. The second phase coincides with the adsorption of P-containing species. Figure 9.19 clearly indicates the presence of a second phase after 400h of immersion. In the initial phase titanium is released either in the form of Ti(OH)n " ")+ or TiO(OH)2. In the second phase adsorption of H2PO4"... [Pg.452]

It can be seen that the first 4 models overlap the data almost exactly. The response predicted by the 4 models is plotted in Figure 4.7 and shows the logarithmic model... [Pg.65]

Table 10.5 Parameters for the logarithmic model based on the binary oil-... Table 10.5 Parameters for the logarithmic model based on the binary oil-...
It is simple to model this equation using a spreadsheet (such as EXCEL), or programs such as MATLAB, or graphics calculators. However, it must be borne in mind that the logarithmic model does not work at very low currents, especially at zero. It is best to start the plots with a current of l.OmAcm. As an example, we have given below the MATLAB script file that was used to produce the graph in Figure 3.1. [Pg.60]

At first, bihemispheric reaction tasks were considered. There was evidence that there existed a linear relation between reaction time and the number of alternatives in choice reaction tasks. The number of alternative stimuli plus the number of alternative responses and the reaction times are strongly related. The precise type of this relation is questionable. The law of Hick which suggests a logarithmic model has dominated this discussion for a long time. The question arises whether new data fit Hick s law or any other law. The results of the preparatory studies of this chapter fit better to a linear relation between reaction time and the number of alternatives. But this is only valid when the number of alternatives is not too high. At higher numbers, the relation is clearly non-linear. [Pg.351]

That analyticity was the source of the problem should have been obvious from the work of Onsager (1944) [16] who obtained an exact solution for the two-dimensional Ising model in zero field and found that the heat capacity goes to infinity at the transition, a logarithmic singularity tiiat yields a = 0, but not the a = 0 of the analytic theory, which corresponds to a finite discontinuity. (Wliile diverging at the critical point, the heat capacity is synnnetrical without an actual discontinuity, so perhaps should be called third-order.)... [Pg.644]

Fig. 2 The dependence on q of the non-zero eigenvalues of the two-dimesional, three-hole model described in the text shows the rapid onset of escape Grom wells as soon as q exceeds unity and the saturation at higher values of q. Also shown is the logarithm of the ratio of the two non-zero eigenvalues. Fig. 2 The dependence on q of the non-zero eigenvalues of the two-dimesional, three-hole model described in the text shows the rapid onset of escape Grom wells as soon as q exceeds unity and the saturation at higher values of q. Also shown is the logarithm of the ratio of the two non-zero eigenvalues.
The group contribution method allows the approximate calculation of solubility by summing up fragmental values associated with substmctural units of the compounds (see Section 7.1). In a group contribution model, the aqueous solubility values are computed by Eq. (12), where log S is the logarithm of solubility, C is the number of occurrences of a substmctural group, i, in a molecule, and is the relative contribution of the fragment i. [Pg.496]

This model then leads us through a thicket of statistical and algebraic detail to the satisfying conclusion that going from small solute molecules to polymeric solutes only requires the replacement of mole fractions with volume fractions within the logarithms. Note that the mole fraction weighting factors are unaffected. [Pg.517]

The Fischer-Tropsch process can be considered as a one-carbon polymerization reaction of a monomer derived from CO. The polymerization affords a distribution of polymer molecular weights that foUows the Anderson-Shulz-Flory model. The distribution is described by a linear relationship between the logarithm of product yield vs carbon number. The objective of much of the development work on the FT synthesis has been to circumvent the theoretical distribution so as to increase the yields of gasoline range hydrocarbons. [Pg.164]

Sterilization of Media First-order kinetics may be assumed for heat destruction of living matter, and this leads to a linear relationship when logarithm of the fraction surviving is plotted against time. However, nonlogarithmic kinetics of death are quite often found for bacterial spores. One model for such behavior assumes inactivation of spores via a sensitive intermediate state by the mechanism ... [Pg.2141]

This small figure may also be compatible with a logarithmic decay [34,57]. Also, the survival probability of a blob of A species embedded in a B sea (separated by a wall of empty sites) decreases in time with exponent 6 = 0.80 0.20 (see Eq. (6)), reminiscent of critical behavior of the ZGB model at the first-order IPT [34]. [Pg.422]

FIG. 10 Micelle size distribution for H2T2 surfactants within the Larson model. The dashed lines show fits to the expected form for spherical micelles (main peak) and cylindrical micelles (tail). Inset shows the tail of the distribution on a semi-logarithmic plot to demonstrate the exponential decay predicted for the cylindrical micelles. (From Nelson et al. [120].)... [Pg.654]

This function is intermediate between the parallel model and the series model and referred to as the logarithmic law of mixture shown in curve 3. The law of mixture is valid for a composite system when there is no interaction in the interface. However, it is natural to consider that interaction will occur in the interface due to contact between A and B. Then considering the creation of interfacial phase C, different from A and B, the following equation can be presented ... [Pg.816]

The FTS mechanism could be considered a simple polymerization reaction, the monomer being a Ci species derived from carbon monoxide. This polymerization follows an Anderson-Schulz-Flory distribution of molecular weights. This distribution gives a linear plot of the logarithm of yield of product (in moles) versus carbon number. Under the assumptions of this model, the entire product distribution is determined by one parameter, a, the probability of the addition of a carbon atom to a chain (Figure 4-7). ... [Pg.126]

FIGURE 3.6 Classical model of agonism. Ordinates response as a fraction of the system maximal response. Abscissae logarithms of molar concentrations of agonist, (a) Effect of changing efficacy as defined by Stephenson [24], Stimulus-response coupling defined by hyperbolic function Response = stimulus/(stimulus-F 0.1). (b) Dose-response curves for agonist of e = 1 and various values for Ka. [Pg.46]


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See also in sourсe #XX -- [ Pg.549 , Pg.550 ]




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