Biomedical Engineering Reference
In-Depth Information
Figure 6.12. Exemplification of the response from a chemical gas sensor during a fermen-
tation process.
implemented as a fermentation system to measure qualitative values of a known
complex chemical and biological process, i.e., the bread fermentation process.
Wide, (1996), shows an interesting experiment, namely that a commercial gas sen-
sor as shown in Fig. 6.12 together with analysis of the sensor data is able to support
an operator to make the optimal decision about the dynamics of a fermentation
process. The signal processing is performed by time series analysis using variance,
kurtosis and shewness, i.e., quantities frequently used in the field of mechanical
analysing applications, deduced from the sensor data as can further be read in the
paper, Wide (1996).
This technique can be compared with the traditional operator used method by
gently pushing a finger on the dough surface and studying the dynamical response
behaviour, i.e., the surface is with some time dependence returning to it's initial
position. A corresponding method that mimics the human sensing procedure has
been proposed in Wide (1995), illustrating that the same strategy is used in a sensor
system, when applying compressed air pulses on the surface and detecting the
reaction, e.g., with an optical distance measuring device to establish the surface
time of recovery.
The mixing process is highly related to rheological aspects that change the
dough properties continuously. In Wide (1999a), an illustrative experiment is pre-
sented that involves a technical-based methodology in correlation with the use of
human experience by learning a system behaviour and when the specific mixing
process is considered optimal.
 
Search WWH ::




Custom Search