"Inverse
solution (UCODE)"
dialog box allows to estimate aquifer parameters by solving inverse
problem with UCODE program (see Poeter E.P., Hill M.C.
Documentation of UCODE, a computer code for universal inverse
modeling // U.S. Geological Survey WaterResources Investigations.
1998. Report 984080).
The dialog is
launched from the main menu "Analysis
> Inverse solution >
UCODE" or function
keys Ctrl+F5.
"Inverse
solution (UCODE)"
dialog boxes.
Explanatory table
"Parameters"
tab


Choose aquifer
parameters for calibration, setting parameters for matching


List
"Parameters
list"

Choose
calibration parameters (checkmark)

"Start
value" text
box

Parameter start
value

"Minimum"
text box

Parameter
minimum value

"Maximum"
text box

Parameter
maximum value

"Perturbation"
text box

Parameter to
calculate sensitivity. 0.01 signifies 1 percent of the parameter
magnitude (recommended)

"Constant
value" text
box

Value of flow
equation parameter excluded from the calibration (not selected in
the parameter list)

Options

See options for
"Matching parameters" dialog
box

"Solver"
list

Choose the
solution for parameter matching. Available for schemes allowing
analysis using several alternative solutions

"Observations"
tab


Drawdown
measurement data in observation wells subject to calibration. Data
available from the ANSDIMAT input file


"Observation
wells" list

Observation
wells for calibration (checkmark)

Observation data
table

Right mouse
click in the table displays a supplemental window with time
conversion for the current observation point

"Time"
column

Observation
time

"s"
column

Drawdown/recovery
value

"Include"
column


"Control
data" tab


Technical
parameters for UCODE program running and parameter estimation. To
change them see user manual for UCODE program

"Output
control" tab


"Run"
button


Run UCODE
program

If convergence
cannot be achieved, or error report appears, try the following to
fix the problem:
1)
change the
starting parameters for matching,
2)
change technical
parameters for UCODE program running ("Control
data"
tab),
3)
remove incorrect
measurements or measurements that are obviously beyond the chosen
conceptual scheme,
4)
reduce the number
of parameters ("Parameter
list" list of the
"Parameter"
tab),
5)
change the solver
(for the conceptual schemes where several solvers can be
applied),
6)
choose other
conceptual scheme.
