Comfort Considerations in Net ZEBs: Theory and Design - Modeling, Design, and Optimization of Net-Zero Energy Buildings - page 119

itself within one generation; the former could be considered as a result of a
long-term adaptation to one given thermal environment, and the latter as a
short-term adaptation that happens within hours to months.
Psychological Adaptation
Psychological adaptation can be considered as an altered perception of a
given thermal environment, caused by an individual's thermal history and
expectation. It is related to the habituation of an individual to a given
thermal condition, since if an individual is repeatedly exposed to a certain
thermal stimulus, his/her perception of the thermal stress, such as his/
her expectation, diminishes. According to this, psychological adaptation is
difficult to evaluate. It also depends on the adaptive opportunities that an
individual can use to customize the indoor environment, since an individual
attemptstotolerate,uptoacertaindegree,uncomfortableconditionsifthey
can control them (Paciuk, 1989).
Behavioral Adaptation
Behavioral adaptation can be considered as the set of all those activities that
are, voluntarily or involuntarily, implemented by an individual in order to
modify the amount of energy and mass exchanges between his/her body
and the surrounding thermal environment. Behavioral adaptation is usually
classified into three types of action: personal , for example, removing one
garment; technological , for example, modifying the set-point temperature
of a building system, opening a window, or operating a shading device; and
cultural , for example, a socially shared practice of resting during the hottest
hours of summer days.
Bases and Formulations of the Adaptive Comfort Models
The models based on the heat balance of the human body were developed
using climate chambers. The adaptive models, however, were derived from
the statistical analysis of data from field studies of people in real buildings,
for example, de Dear, Brager, and Cooper (1997) and Nicol and McCartney
(2001). Humphreys (1978) and Auliciems (1981) demonstrated that,
specifically in buildings in free-floating mode, the neutral temperatures
are mostly linked to the outdoor temperatures, rather than to the indoor
conditions as assumed by the rational model. The rational models are
deterministic models; instead the adaptive models are derived from a
black-box approach and relate indoor neutral temperatures to outdoor