Decagon Devices KD2 Pro Operator's Manual page 63

can give a wide range of results depending on the starting
point of the iteration because the single needle problem is sus-
ceptible to getting stuck in local minima. The linear least
squares computation is also very fast.
References:
1. Carslaw, H.S. and J.C. Jaeger (1959) Conduction of Heat in
Solids, 2nd Edition. Oxford, London.
2. Abramowitz, M. and I. A. Stegun (1972) Handbook of math-
ematical functions. Dover Publications, Inc., New York.
3. Marquardt, D. W. (1963) "An algorithm for least-squares
estimation of nonlinear parameters" J. Soc. Indust. Appl.
Math. 11:431-441.
4. Kluitenberg, G. J., J. M. Ham, and K. L. Bristow (1993)
"Error analysis of the heat pulse method for measuring
soil volumetric heat capacity" Soil Sci. Soc. Am. J. 57:1444-
1451.
KD2 Pro Operator's Manual
8. KD2 Pro Theory
59