Comparison of variability

R. Heikka, P. Minkkinen, and V-M Taavitsainen, Comparison of variable selection and regression methods in multivariate calibration of a process analyzer. Process Control and Quality, 6, 47-54 (1994). 

Heikka, R., Minkkinen, P. and Taavitsainen, V.-M., Comparison of Variable Selection and Regression Methods in Multivariate Calibration of a Process Analyzer Process Contr. Qual. 1994, 6, 47-54. 

Deconvolution of spectra (energy distribution of orbitals and widths of bands) accomplished by comparison of variable energy photoelectron spectra and SCF-Jfct -SW ground state calculation. 

TABLE I. Comparison of Variability Between Diffusion Cell Types... 

Table 17.1. Comparison of variables used in different prognostic models for medium- to long-term outcome after transient ischemic attack and stroke in the Hankey, Kernan (SPI-II) and Howard models...

Example Comparison of variables for the conversion of a conventional rectification plant ... 

Severtsova, E.A. Severtsov, A.C. (2005). Interpopulation comparison of variability o gastrulation of Common frog embryos living in conditions of anthropwgenic polluted ponds. Ontogenez. T. 36. Nq2. p. 110-122. (Russ.). 

Artemisinin combinations In a retrospective study of 46 adults in Cote D Ivoire who were given a 3-day regimen of combinations with artemisinin (lumefantrine, n=20 amo-diaquine, n = I3 mefloquine, n = 7 and piperaquine + trimethoprim, n = 6) and who developed hepatorenal failure, 12 died and 34 recovered within a median of 3-12 days after withdrawal of the combination therapy [IH]. In a comparison of variables between those who died and those who survived. 

Because of the inherent variability in the length and branching neurites of control as well as experimental neurons, we use one-way analysis of variance (ANOVA) for statistical analysis of the data. Analysis of variance allows comparison of variability within as well as between samples, resulting in a more complete assessment of significant changes. 

A comparison of variable operation costs for a devolatilisation extruder versus purge air treatment through a regenerative thermal oxidation unit is given in Table 12.8 below. The calculation is based on an electricity price of EUR 0.05/kWh and a fuel price of EUR... 

Table 1.2 Comparison of variable CVD fabrication protocol/conditions utilised and the resultant variability in graphene quality obtained... 

JA Stillman. Context effects in judging taste intensity A comparison of variable line and category rating methods. Percept Psychophys 54(4) 477-484, 1993. 

To define the thennodynamic state of a system one must specify fhe values of a minimum number of variables, enough to reproduce the system with all its macroscopic properties. If special forces (surface effecls, external fields—electric, magnetic, gravitational, etc) are absent, or if the bulk properties are insensitive to these forces, e.g. the weak terrestrial magnetic field, it ordinarily suffices—for a one-component system—to specify fliree variables, e.g. fhe femperature T, the pressure p and the number of moles n, or an equivalent set. For example, if the volume of a surface layer is negligible in comparison with the total volume, surface effects usually contribute negligibly to bulk thennodynamic properties. 

The essential slow modes of a protein during a simulation accounting for most of its conformational variability can often be described by only a few principal components. Comparison of PGA with NMA for a 200 ps simulation of bovine pancreatic trypsic inhibitor showed that the variation in the first principal components was twice as high as expected from normal mode analy-si.s ([Hayward et al. 1994]). The so-called essential dynamics analysis method ([Amadei et al. 1993]) is a related method and will not be discussed here. 

Laboratory experiments using rodents, or the use of gas analysis, tend to be confused by the dominant variable of fuel—air ratio as well as important effects of burning configuration, heat input, equipment design, and toxicity criteria used, ie, death vs incapacitation, time to death, lethal concentration, etc (154,155). Some comparisons of polyurethane foam combustion toxicity with and without phosphoms flame retardants show no consistent positive or negative effect. Moreover, data from small-scale tests have doubtful relevance to real fine ha2ards. 

In an economic comparison of these three common abatement systems, a 1991 EPA study (58) indicates extended absorption to be the most cost-effective method for NO removal, with selective reduction only matching its performance for small-capacity plants of about 200—250 t/d. Nonselective abatement systems were indicated to be the least cost-effective method of abatement. The results of any comparison depend on the cost of capital versus variable operating costs. A low capital cost for SCR is offset by the ammonia required to remove the NO. Higher tail gas NO... 

The composition of dairy substitutes is highly variable and generally represents the least-cost formulation consistent with consumer acceptance of the product. These imitations invariably have lower fat and protein levels than the dairy products that they are made to resemble. The gross compositions of filled milk, meUorine, synthetic milk, sour cream, coffee whiteners, whipped toppings, and cheese are Hsted in Table 10. A comparison of the composition of certain dairy products and their substitutes is presented in Table 11. 

Quahtative variables can be broken down into two categories. The first consists of those variables whose specific effects ate to be compared directiy eg, comparison of the effect on performance of two proposed preparation methods or of three catalyst types. The requited number of conditions for such variables is generally evident. Such variables are sometimes referred to as fixed effects or Type I variables. 

Plausibility Analysis A comparison of values for process variables that allows faults in the measurement channels of the safety system to be recognized while the process is still in its normal operating range. 

This long-term thermal performance of a material is tested alongside a second, control, material which already has an established RTI and which exhibits a good performance. Such a control is necessary because thermal degradation characteristics are sensitive to variables in the testing programme. Since the control material will also be affected by the same unique combination of these factors during the tests, there is a valid basis for comparison of test and control materials. 

The micropore volume varied from -0.15 to -0.35 cmVg. No clear trend was observed with respect to the spatial variation. Data for the BET surface area are shown in Fig. 14. The surface area varied from -300 to -900 mVg, again with no clear dependence upon spatial location withm the monolith. The surface area and pore volume varied by a factor -3 withm the monolith, which had a volume of -1900 cm. In contrast, the steam activated monolith exhibited similar imcropore structure variability, but in a sample with less than one fiftieth of the volume. Pore size, pore volume and surface area data are given in Table 2 for four large monoliths activated via Oj chemisorption. The data in Table 2 are mean values from samples cored from each end of the monolith. A comparison of the data m Table 1 and 2 indicates that at bum-offs -10% comparable pore volumes and surface areas are developed for both steam activation and Oj chemisorption activation, although the process time is substantially longer in the latter case. 

Figure 10 Comparison of hardness 3 sigma variability ratings fluoroelastomer compound.

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