(25) Calculation of frostline penetration in high-voltage cable trench

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An extract from appendix c of Calculations of Frostline Penetration in High-Voltage Cable Trench, HATHI TRUST (view/download), James K. Landman, Bureau of Reclamation Engineering and Research Center (REC-ERC-77-7), DEC 1977.
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In the early work of this investigation, much of the tedious data condensation was greatly simplified by the use of a programmable pocket calculator. In this example, the Hewlett-Packard HP-25 was used to tabulate air-freezing index data and to generate Y₂(ρ) values for the trial-and-error solution of the coefficient of proportionality transcendental function.
The two programs that follow have applications for the type of data described in this work. While the programs were written specifically for the HP-25, they could be easily adapted to any of the other programmable calculators made by Hewlett-Packard. With some minor changes in the programs, other manufacturer's units may be usable.
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replete with equations, diagrams, figures & program (pages 37-41) descriptions & listings: enjoy!

BEST!
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