Question

In process modeling, experimental observations provide:

(a) Structure of the model

(b) Non-numerical values of coefficients

(c) Non-numerical values of variables

(d) Numerical values of coefficients

I have been asked this question in an interview.

The origin of the question is Monitoring and Control of Bioreactors topic in section Reactor Engineering of Bioprocess Engineering

Answer 1

Right option is (d) Numerical values of coefficients

To elaborate: Traditionally, models are based on a combination of ‘theoretical’ relationships which provide the structure of the model, and experimental observations which provide the numerical values of coefficients. For biological processes, specifying the model structure can be difficult because of the complexity of cellular processes and the large number of environmental factors which affect cell culture. Usually, bioprocess models are much-simplified approximate representations deduced from observation rather than from theoretical laws of science. As an example, a frequently-used mathematical model for batch fermentation consists of the Monod equation for growth and an expression for rate of substrate consumption as a function of biomass concentration.