Sequoia LISST-100X, Руководство пользователя

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LISST-100X User’s Guide 3
Simpler descriptions of principles and practice are offered in a
separate study by Agrawal et al., 1991
1
. A more up to date
description of the technology and its application is provided by
Agrawal & Pottsmith, 2000
2
.
We explain the inversion process as follows: Let E be the 32-
element data vector that contains the angular scattering energy
sensed by the 32 silicon rings. It is related to the volume
distribution
3
via
E = K N
V
where K is the scattering property kernel matrix and N
V
is the
volume distribution.
The volume distribution is obtained by inverting the above
equation. Included with the LISST-100X instrument, we have
provided software that obtains the inverted volume distribution N
V
1
Agrawal, Y.C., I.N. McCave, and J.B. Riley, 1991: "Laser diffraction size analysis," in Principles, methods and applications
of particle size analysis , J.P.M. Syvitski, editor, Cambridge University Press, pp. 119-128.
2
Agrawal, Y. C. and H. C. Pottsmith, 2000: Instruments for Particle Size and Settling Velocity Observations in Sediment
Transport, Marine Geology, 168, pp 89-114.
3
The volume distribution is related to the number distribution via N
V
= a
3
n(a). It represents the volume concentration of
particles in the size range a to a + da . The results from the LISST instruments provide the volume concentration of
particles in each of 32 size classes. The size classes are log-spaced from the range 1.25-250 microns (Type-B
instruments) or 2.5-500 (Type-C). See Appendix B for further details.