Effect on predictivity

Methanol eoncentration has essentially no effect on predicted water content of the liquid-hydrocarbon phase. The water eontent (not shown in the tables) was about 0.02 mol%. 

Yoder showed that radiation heat transfer and axial conduction heat transfer in the tube wall have a negligible effect on predicting wall temperatures. The following equations were used by Yoder and Rohsenow (1980) as well as previous investigators such as Bennett et al. (1967b), Hynek (1969), and Groeneveld (1972). 

Figure 16.17a schematically shows the individual subcomponents of these three major modules (McRae et al., 1982a), and Fig. 16.17b shows a typical chemical submodel in more detail (Dabdub and Seinfeld, 1996). In the following sections, we shall briefly refer to some of the individual subcomponents of these three modules, particularly with respect to effects on predicted concentrations of secondary species. However, consistent with the focus of this book on atmospheric chem-... 

Given the numerous potential uncertainties due solely to uncertainties in the chemistry, particularly the VOC chemistry and how it is incorporated into models, it is clearly important to understand which are likely to have the most important net effects on predicted concentrations. A number of studies have been carried out to address this issue (e.g., see Hough and Reeves, 1988 Hough, 1988 Dodge, 1989, 1990 Chock et al., 1995 and Olson et al., 1997). Sensitivity analyses have been performed for a number of models. For typical approaches, see Derwent and Hov (1988), Milford et al. (1992), and Gao et al. (1995, 1996). 

For example, Kumar and Russell (1996) examined the effect on predicted ozone levels in the Los Angeles area of two different approaches now used for incorporating meteorology into a grid-based Eulerian model. The diagnostic approach is based on field measurements of the needed meteorological variables and in-... 

Hileman GA, Upadrashta SM, Neau SH. Drug solubility effects on predicting optimum conditions for extrusion and spheronization of pellets. Pharm Dev Tech 1997 2(l) 43-52. 

Results of the four models (Figure 9a) illustrate the effect on predicted recovery rates of including various alkalinity-generating processes. Models 1 and 2 probably yield upper and lower limits of the time required to recover to the preacidification alkalinity level. Model 3 probably yields an underestimate of recovery time, in that it does not consider the need to neutralize acidified surficial sediments (and restore base cations on sediment-exchange sites that have been lost during the last years of acid loading). Model 4 probably yields the most accurate estimate of recovery time, but it does not provide a functional relationship for the cation-production term. Based on Model 4, the north basin will reach 50% of the preexperimental alkalinity concentrations in 3-5 years and 90% in 8 years. Complete recovery is predicted to occur in 12.5-15 years. 

Perturbation of Spectra to Evaluate Effect on Predictive Power of Model... 

There are some difficulties we should be aware of just the same. The maximum that is supposed to appear at co = 0 shows up in the INM calculations as a full-blown divergence (43,44). Indeed this infinity is just one instance of the fundamental problems with INMs at zero frequency. It probably should not be a surprise that a theory that pretends that basic liquid structure does not change with time is going to be ill-suited to studying behavior at the lowest frequencies. The same level of theory predicts liquid diffusion constants to be identically zero, for example. Fortunately, realistic molecular vibrational frequencies tend to be well outside this low-frequency regime, so the effects on predicted Tis are likely to be minimal. Still, as we shall note in Section VI, not every aspect of vibrational spectroscopy will be quite so insulated from this basic issue. 

During adverse meteorological events the use of an interface module to model dispersion parameters can have the advantage to reduce forecast error effects on predicted concentrations. Anyway, further analysis showed that the discussed results are strongly dependent on the radiation scheme used by RAMS model. 

Water or water plus methanol has negligible effect on predicted liquid-hydrocarbon knockout. 

Spangler et al. [93] considered nonlinear instability of a straight liquid jet xmder the influence of both capillary forces and aerodynamic interactions with an external gas. They showed that the gas phase interaction is important even at relatively low jet velocities. The presence of the gas leads to a swelling in the trough region of the wave. Aerodynamic interactions had very httle effect on predicted droplet sizes... 

VarUition In Cross Sections and Methods Effect on Predicted Multiplication Factor (flkA)... 

This review has concentrated on the information which has been obtained from very careful studies of the kinetics of stratospheric reactions. These studies have almost always involved spectroscopic measurements of the rates of disappearance of an atom or free radical under pseudo-first-order conditions, i.e. in the presence of excess of the other reagent. Product analyses have rarely been carried out because of the small amounts of product formed fixim the low concentrations of transient species employed. An important but rather neglected area of selectivity in atmospheric reactions is the possible occurrence of parallel reaction paths leading to different products. In some cases the alternative reaction path could have a significant effect on predicted ozone depletions. For instance, it is generally assumed that the reaction CIO + HO2 yields exclusively HOQ + O2 rather than the energetically feasible HQ + O3. Similarly the photolysis of HOCl is believed to yield exclusively HO + Cl rather than HQ + O. If HQ were formed in either of these processes its relatively high stability in the stratosphere would reduce the proportion of chlorine present as Q and QO and hence decrease the predicted ozone depletions. 

PivlimiiKiry sensitivity analyses results suggest that incorporation of correlation timoiig A, S does have an effect on predicted THDF for these five radioele-... 

A multivariate analysis was conducted that included N intake and ME intake as covariates in predicting N output in faeces, urine and milk. Metabolizable intake had a significant effect on predicting urinary N excretion and milk N secretion but not faecal N excretion. It should be noted that ME intake already includes faecal and urinary energy as part of the calculation, therefore, correlations are expected. The residual standard deviations from the multivariate arralysis including ME intake as a covariate were 13.8, 27.9 and 15.0 g/d. The prediction equations for urinary N excretion and milk N secretion (which had significant effect of ME intake) were ... 

A multivariate analysis was conducted that included N intake and metabolizability as covariates in predicting N output in faeces, urine and milk. Metabolizability had a significant effect on predicting... 

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