Sum mean

They include simple statistics (e.g., sums, means, standard deviations, coefficient of variation), error analysis terms (e.g., average error, relative error, standard error of estimate), linear regression analysis, and correlation coefficients. 

To be concrete, if we take MSG and IMP as the standards for both groups of substances, u and v represent the totals of acidic amino acids and nucleotides in terms of the concentrations of MSG and IMP, respectively. In our taste space, the sum means combining the components of two solutions, and the scalar multiple means concentrating or diluting of a solution. The absolute value means the intensity of umami of a solution in terms of the concentration of, say, MSG alone. 

The primes near the sum mean the term with subscripts j = k is excluded. The sum subscripts / , mean that they can vary independently from subscripts l,m, which correspond to the k -th sphere. 

This sum means that in the non-adiabatie approaeh, the motion of the system involves many potential energy surfaees at the same time (see Fig. 6.15d). 

Fig. 2 Bland and Altman plot. Segmental sum mean resistance (fi) between methods 3 and 4...

The law of the slowness involves the sum function, so the result may contain numerous sums, meaning that concentrations are not separated from each other and the temperature. 

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