Q2 Z2,(Q2) Z2(Q2) - Institute for Water Resources - U.S. Army

wide range of output would have to be altered. This would probably
result in a U-shaped long-run average cost curve, which if flat at .
all would be flat over a narrower range of output possibilities. Of
course, the level of the curve would be higher than that calculated
by Howe, even if the same input costs were used, simply because of .
the inclusion of delay time. .
Though not a component of the tow process function, an analysis
of waterway capacity and tolls is presented in Chapter IV. This is
an outgrowth of the locking model and may be viewed as an applica-
tion of welfare economics to tow and waterway operations. The anal-
,
ysis provides a method of measuring the capacity of a waterway in ,
terms of the utilization of its locks. A method of calculating the
optimal toll to be charged for use of the waterway is also developed.
The toll is optimal in the sense that if imposed it would equate
private and social coats. Methods are, of course, provided for cal-
culating these costs. A recapitulation of resurts ends the chapter.
Chapter V is an application of the method of Chapter III to the
case of rail freight trains. For the purpose of the rail analysis,
there is no previously existing process function as there was for
the case of barge tows. However, there are, much more widely accepted
and well known engineering relationships available for rail opera-
tions than there are for barge operations. The chapter proceeds to
.exploit these relationships in developing the rail linehaul process
\
function. .
The two most important functions in determining, the speed of a
rail train are, as discussed in Chapter III, the tractive-effort.
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