F. D. FARD ET AL.
Copyright © 2013 SciRes. ENG
ues can be used for distinguishing these two postures.
Figu r e 8 shows that the values of standard deviation vary
from posture 1 to posture 4. According to Figure 9
skewness values of posture 2 have negative signs, and
skewness values of posture 3 have positive signs while
those of postures 1 and 4 are close to zero (negative or
positive). So these three groups (posture 2, posture 3,
posture 1 and 4) can be distinguished by the skewness
coefficient. Finally, Figure 10 shows that kurtosis coef-
ficients of posture 2 and 3 are generally larger than those
of postures 1 and 4. This sounds reasonable, since fitted
normal distributions of postures 1 and 4 are similar to
standard normal distribution, while those of postures 2
and 3 generally have higher peaks.
4. Conclusions
A continuous-time pressure monitoring system is pre-
sented. Due to its useful information about patient’s
movement history, feasibility for simultaneous monitor-
ing of pressure and alarming options, it is proposed that
this system can be utilized for pressure ulcer prevention.
Sitting posture identification is possible using the pre-
sented system. A method for detecting different sitting
postures has been proposed and verified. It is suggested
that preventing pressure ulcers in wheelchair-bound pa-
tients can be performed using the sitting posture detec-
tion method.
Spatial resolution of the designed system can be im-
proved in future works by increasing the number of
pressure sensors. The presented pressure monitoring sys-
tem can be expanded to be used in mattresses of bedrid-
den patients.
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