Theoretical Models for Thermoregulation in Man
271
At specifiable intervals, the program can be made to branch to an output
sub-routine which can provide values for any and all of the variables and
any values derived from them. Such output can be in the form of a graph or
a table.
Application of Models of Thermoregulation in Man
It is evident that almost any experiment or condition can be simulated
with the model by applying identical experimental conditions. The coefficients and values of the controlled system are based on careful evaluation
of pertinent data in the literature and should not be changed unless there
is compelling reason to do so, such as new findings or new measurements of
heat capacitances, heat conductances, basal rates of metabolic heat production and of evaporative heat loss, and basal local blood flow rates. Naturally
if this model of man is to be modified for other homoiotherms, all these
basal values will need readjustment.
The controller of the present model calls upon a number of other
biological control systems for its proper operation such as the respiratory
control system for supply of oxygen and release of carbon dioxide; the
cardiovascular control system for supplying the required blood flow to all
regions; the water volume control system for making water available for
sweating, etc. As formulated here, no limits have been assigned to the
efficacy of any of these control systems, nor is there a limit to the evaporation of secreted sweat. If required, it is relatively simple to put limits on the
capabilities of all these systems so that exhaustion, dehydration and circulatory limits can be properly evaluated.
In studies in which the objective is the evalution of practical situations,
such as tolerance times, comparisons of stressful conditions, etc., the
precise values of the controller coefficients in the thermoregulatory controller are not of primary importance, and in the model, the values given in
Table 3 will serve adequateh'.
Table 3. Controller coefficients for appled studies with the thermoregulation model
Coefficient
HSW
60
Kcal·-h-1.°C-2
WSW
100
Kcal· h-1.OC-2
DIL
100
1· h-l.°C-l
ST
10
1· h-1.OC-l
PC
60
Kcal· h-1.OC-l
CC
60
Kcal· h-1 .oC-2
If the purpose of the model study is to improve understanding of the
thermoregulatory controller itself, then the emphasis should be on variation
in value and character of the controller coefficients. It is e.g. noticed in
271
At specifiable intervals, the program can be made to branch to an output
sub-routine which can provide values for any and all of the variables and
any values derived from them. Such output can be in the form of a graph or
a table.
Application of Models of Thermoregulation in Man
It is evident that almost any experiment or condition can be simulated
with the model by applying identical experimental conditions. The coefficients and values of the controlled system are based on careful evaluation
of pertinent data in the literature and should not be changed unless there
is compelling reason to do so, such as new findings or new measurements of
heat capacitances, heat conductances, basal rates of metabolic heat production and of evaporative heat loss, and basal local blood flow rates. Naturally
if this model of man is to be modified for other homoiotherms, all these
basal values will need readjustment.
The controller of the present model calls upon a number of other
biological control systems for its proper operation such as the respiratory
control system for supply of oxygen and release of carbon dioxide; the
cardiovascular control system for supplying the required blood flow to all
regions; the water volume control system for making water available for
sweating, etc. As formulated here, no limits have been assigned to the
efficacy of any of these control systems, nor is there a limit to the evaporation of secreted sweat. If required, it is relatively simple to put limits on the
capabilities of all these systems so that exhaustion, dehydration and circulatory limits can be properly evaluated.
In studies in which the objective is the evalution of practical situations,
such as tolerance times, comparisons of stressful conditions, etc., the
precise values of the controller coefficients in the thermoregulatory controller are not of primary importance, and in the model, the values given in
Table 3 will serve adequateh'.
Table 3. Controller coefficients for appled studies with the thermoregulation model
Coefficient
HSW
60
Kcal·-h-1.°C-2
WSW
100
Kcal· h-1.OC-2
DIL
100
1· h-l.°C-l
ST
10
1· h-1.OC-l
PC
60
Kcal· h-1.OC-l
CC
60
Kcal· h-1 .oC-2
If the purpose of the model study is to improve understanding of the
thermoregulatory controller itself, then the emphasis should be on variation
in value and character of the controller coefficients. It is e.g. noticed in