CE En 547 - Exam #2 KEY

Fall Semester 2018

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1. (1 pt each) True or False:

a. T F  (calibration) When computing a weighted error norm such as the sum of the squared weighted residuals, the weight for a particular observation is typically inversely proportional to the size of the calibration target (conf. interval).

b. T F  (modflow) You can improve the convergence of an oscillating MODFLOW model by reducing the convergence tolerance.

c. T F  (gms) You can have multiple 2D scatter point sets in GMS, and each scatter point set can have multiple data sets.

d. T F  (calibration) The RMS error norm is generally greater than the MAE error norm.

e. T F  (gms) When interpolating MODFLOW grid layer elevations using the GMS interpolation tools, the more points you have, the less difference it makes which interpolation scheme you use.

f. T F  (modflow) If a cell is going dry in a MODFLOW model, it can often be rectified by either decreasing the recharge or increasing the K.

g. T F  (modflow) With a typical MODFLOW solver, increasing the acceleration parameter will make the model converge more rapidly but it may become unstable.

h. T F  (gms) You can have multiple sets of overlapping polygons in a single coverage in a GMS conceptual model as long as each polygon only has one property.

i. T F  (calibration) You can choose river conductance as one of your parameters for automated calibration with PEST.

j. T F  (calibration) PEST is an acronym derived from Parameter Evaluation Software Tool.