[GRASS-SVN] r30295 - grass/trunk/raster/simwe/r.sim.sediment

[svn_grass at osgeo.org]

Author: helena
Date: 2008-02-23 00:02:23 -0500 (Sat, 23 Feb 2008)
New Revision: 30295

Modified:
   grass/trunk/raster/simwe/r.sim.sediment/description.html
Log:
non-functional flags removed

Modified: grass/trunk/raster/simwe/r.sim.sediment/description.html
===================================================================
--- grass/trunk/raster/simwe/r.sim.sediment/description.html	2008-02-22 18:14:09 UTC (rev 30294)
+++ grass/trunk/raster/simwe/r.sim.sediment/description.html	2008-02-23 05:02:23 UTC (rev 30295)
@@ -9,31 +9,35 @@
 function Monte  Carlo method, to provide robustness necessary for 
 spatially variable conditions and high resolutions (Mitas and Mitasova 
 1998).  Key inputs of the model include the following raster maps:
- elevation (<i>  elevin</i>), flow gradient given by the first-order partial 
+ elevation (<i>  elevin</i> [m]), flow gradient given by the first-order partial 
 derivatives of elevation field (<i> dxin</i> and <i>dyin</i>), 
-overland flow water depth (<i> wdepth</i>), detachment capacity coefficient (<i>detin</i>), 
-transport capacity coefficient (<i>tranin</i>), critical shear stress (<i>tauin</i>) 
+overland flow water depth (<i> wdepth</i> [m]), detachment capacity coefficient 
+(<i>detin</i> [s/m]), transport capacity coefficient (<i>tranin</i> [s]), 
+critical shear stress (<i>tauin</i> [Pa]) 
 and surface  roughness coefficient called Manning's n (<i>manin</i> raster map). 
 Partial derivatives can be computed by <a href="v.surf.rst.html">v.surf.rst</a>
 or <a href="r.slope.aspect.html">r.slope.aspect</a>
-module. The data are automatically converted data from feet to metric
-system using database/projection information. The water depth file can be
-computed using <a href="r.sim.water.html">r.sim.water</a>
+module. The data are automatically converted from feet to metric
+system using database/projection information, so the elevation always should be in meters. 
+The water depth file can be computed using <a href="r.sim.water.html">r.sim.water</a>
 module. Other parameters must be determined using field measurements or
 reference literature (see suggested values in Notes and References). <br>
 
 <p>
 Output includes transport capacity raster map <i>tc</i>  in [kg/ms],
 transport capacity limited erosion/deposition raster map
-<i>et</i> [kg/m<sup>2</sup>s], sediment flow rate raster map 
-<i>flux</i> [kg/ms], and net erosion/deposition raster map [kg/m<sup>2</sup>s]. 
-Simulation time is controled by <i> niter</i> parameter.  The default value is 1000,
-depending on complexity of terrain, land cover and size of the area, several thousand
- iterations may be needed to reach the steady state. Output
-files can be saved during simulation using <i>outiter</i> parameter
+<i>et</i> [kg/m<sup>2</sup>s]i that are output almost immediately and
+can be viewed while the simulation continues. Sediment flow rate raster map 
+<i>flux</i> [kg/ms], and net erosion/deposition raster map [kg/m<sup>2</sup>s]
+can take longer time depending on time step and simulation time. 
+Simulation time is controled by <i> niter</i> [minutes] parameter. 
+<!-- Output files can be saved during simulation using <i>outiter</i> parameter
 defining simulation time step for writing output files. This option requires
 time series flag <i>-t</i>. Files are saved with suffix   containing
-iteration number (e.g. name.500, name.1000, etc.).<br>
+iteration number (e.g. name.500, name.1000, etc.) representing time in seconds.
+-->
+If the resulting erosion/deposition map is noisy, higher number of walkers,
+given by <i>nwalk</i> should be used. 
 <br>
 
 <h2>NOTES</h2>