The phrase "a useful approximation of" is correct and usable in written English.
It can be used when discussing a simplified or estimated representation of something that is not exact but serves a practical purpose.
Example: "In physics, we often use a useful approximation of the gravitational force to simplify complex calculations."
Alternatives: "a helpful estimate of" or "a practical representation of".
The C + NVC model with the incorporation of Wu et al. (2009) outputs was adapted for use in this paper, it was shown to give a useful approximation of the difference between scenarios, and could be further utilised with specific wildfire management data (i.e. pre-suppression efforts–such as prescribed burning) if and where available.
This theory provides a useful approximation of the historical changes that have taken place in populations in many different regions of the world.
The body mass index is a useful approximation of body fat, but it can be misleading for muscular athletic individuals, like President Bush, who would be considered overweight, as the article notes.
A useful approximation of Eqs.
Thus the MC characterizes a point at which we have constructed a useful approximation of the complete system.
Economists have extrapolated a useful approximation of uncovered interest rate parity that follows intuitively from these assumptions.
Although this exact cancellation of the radial and angular dispersion effects provides a useful approximation for many types of proton pairs, the 3-fold rotational jumps of methyl protons deviates strongly from spherical isotropy.
The initial rate of development of constitutional undercooling is shown to be equivalent to the growth restriction factor and is a useful approximation for the effect of solute on grain size when potent nucleant substrates are present.
The similar sensitivities of plateau-phase cultured cells and cells taken directly from large growing tumours is direct evidence that plateau-phase cultures are a useful approximation to the state of cytokinetic resistance to chemotherapeutic drugs that prevails in solid tumours, although they may not fully reflect the cytokinetic heterogeneity present in tumours.
The method appears to be a useful approximation for a wide variety of problems.
These assumptions are not too restrictive and the solution appears to be a useful approximation for a broad range of material-mill combinations.
