Example i54: 3D Duodenum - Body Surface Potential and Magnetic Field

This example takes the dipole source per element (from example i53) in a 3D duodenum as an input to compute the body surface potential and magnetic field external to the torso.

The corresponding body surface potential and magnetic fields are shown below at two different specific time. The magnetic field vectors have been translated to the left for visual purposes - in reality they are centred over the torso.

t=5s	t=298s

The comfile run by this example is as follows:

set Num_threads 1
# Set up a regions for the torso
$torso = 1;

# Set up a class for the laplace problem
$laplace = 1;

# Read in geometry of the torso
fem define para;r;$example/torso
fem de coor 3,1
fem define nodes;r;$example/skin
fem de base;r;$example/torso
fem define ele;r;$example/skin

# Group nodes to be applied for the .ipinit
fem group node 1009 as bottom reg $torso
fem group node 1262 as top reg $torso
fem group node 1010..1261,1263..1298 as middle reg $torso

# Define the laplace problem in the torso
fem define eq;r;$example/skin reg $torso class $laplace
fem define mate;r;$example/skin reg $torso class $laplace 
fem define ini;r;$example/skin reg $torso class $laplace 
fem define solve;r;$example/skin reg $torso class $laplace   

# Perform an initial solve
fem solve reg $torso class $laplace

# Magnetic field at 19 electrodes recording place for SQUID
fem def data;r;$example/squid_19 field num_fields 3 reg $torso

# Read in the dipole source and multiply -1 to correct the dipole direction
fem define sour;r;$example/dipoles_elem reg $torso scale -1

# Change the location of the dipole
fem change source translate by 0,0,0
fem de sour;w;dipole_changed as dipole 
fem export sour;dipole_changed as dipole


for $M (0..5)
{
$time=$M
# Apply the sources to the laplace problem
fem update sour reg $torso class $laplace time $time

# Solve the laplace problem
fem solve reg $torso class $laplace
fem export node;torso_pot_$time reg $torso class $laplace field as torso

# eval solu magnetic [data/mfi]
# both-primary/secondary
# squid-config 3- Z vectors @ 19 positions
fem eval solu mag from data both squid_config 3 time $time
fem export data;torso_mag_$time as torso_mag field_num 1..3 field_name mag
}

Files used by this example are:

Name                 Modified     Size

example_i54.com      02-Nov-2005  1.7k
dipoles_elem.ipsour  02-Nov-2005  1.0M
skin.ipelem          02-Nov-2005  102k
skin.ipequa          02-Nov-2005  1.4k
skin.ipinit          02-Nov-2005  665 
skin.ipmate          02-Nov-2005   54 
skin.ipnode          02-Nov-2005  263k
skin.ipsolv          13-Apr-2007  1.3k
squid_19.ipdata      02-Nov-2005  2.1k
torso.ipbase         02-Nov-2005   12k
torso.ippara         02-Nov-2005  5.9k

Download the entire example:

Name                      Modified     Size

examples_i_i5_i54.tar.gz  18-Jan-2011  295k

Testing status by version:

Testing status by file:

• torso_mag_5.exdata
  

  i686-linux
  Success	cm:	ndiff test: no significant differences with generic answer.
  Success	cm-debug:	ndiff test: no significant differences with generic answer.
  mips-irix
  Success	cm:	ndiff test: no significant differences with generic answer.
  Success	cm-debug:	ndiff test: no significant differences with generic answer.
  Success	cm-debug-clear-malloc:	ndiff test: no significant differences with generic answer.
  Success	cm-debug-clear-malloc7:	ndiff test: no significant differences with generic answer.
  Success	cm64:	ndiff test: no significant differences with generic answer.
  Success	cm64-debug:	ndiff test: no significant differences with generic answer.
  rs6000-aix
  Success	cm:	ndiff test: no significant differences with generic answer.
  Success	cm-debug:	ndiff test: no significant differences with generic answer.
  Success	cm64:	ndiff test: no significant differences with generic answer.
  Success	cm64-debug:	ndiff test: no significant differences with generic answer.
  x86_64-linux
  Success	cm:	ndiff test: no significant differences with generic answer.
  Success	cm-debug:	ndiff test: no significant differences with generic answer.

  
  
• torso_pot_5.exnode
  

  i686-linux
  Success	cm:	ndiff test: no significant differences with generic answer.
  Success	cm-debug:	ndiff test: no significant differences with generic answer.
  mips-irix
  Success	cm:	ndiff test: no significant differences with generic answer.
  Success	cm-debug:	ndiff test: no significant differences with generic answer.
  Success	cm-debug-clear-malloc:	ndiff test: no significant differences with generic answer.
  Success	cm-debug-clear-malloc7:	ndiff test: no significant differences with generic answer.
  Success	cm64:	ndiff test: no significant differences with generic answer.
  Success	cm64-debug:	ndiff test: no significant differences with generic answer.
  rs6000-aix
  Success	cm:	ndiff test: no significant differences with generic answer.
  Success	cm-debug:	ndiff test: no significant differences with generic answer.
  Success	cm64:	ndiff test: no significant differences with generic answer.
  Success	cm64-debug:	ndiff test: no significant differences with generic answer.
  x86_64-linux
  Success	cm:	ndiff test: no significant differences with generic answer.
  Success	cm-debug:	ndiff test: no significant differences with generic answer.

  
  

Graphical output from this problem is given here.

Html last generated: Sun Mar 6 05:51:40 2016

Input last modified: Mon Jan 17 14:11:45 2011