SimSurface Settings

The Settings dialog box allows the user to set various options relating to the physical setup of the charge-box system as well as some of the details of the numerical algorithm employed in the model. From a scientific standpoint, these "details" are one of the most important parts of any activity involving Surface. How "good" your answer is depends on how "good" your algorithm is. At the same time, a scientist wants to do a lot of science, so they have to figure out how to get a "good" answer in the least possible amount of time. For example, setting the cooling factor to an extremely slow rate (like .999) and doing 1000 calculations per step may give a very accurate answer, but it will take a long time to get that answer. It may be the case that a setting of .9 for the cooling fator and 500 calculations per step gives essentially the same answer in a much shorter time period. These and other similar questions are part of what users of Surface should be exploring in order to get a feel for what scientists do. The settings dialog box looks like this:

The meanings of these settings are as follows:

Charge on walls:

Sets the amount of charge on walls of box. A setting of ten gives that wall the amount of charge that would result if ten charges (like the ones in the box) were ground up into itty bitty pieces and evenly distributed along the wall.

Annealing Parameters

Number of charges
Sets (gasp!) the number of charges. There are also tools (add a charge and remove a charge) that can do this.
Cooling factor
This is a multiplier that changes the temperature at each step. At .5, the temperature is reduced by half at each step, at .9, the temperature is reduced to 90 percent of the previous temperature at each step, etc.
Trials per temperature
This sets the number of attempted moves made at each temperature setting.
Temp to step ratio
Sets how big a step each electron can take at a particular temperature.

Options

Animate Relaxation Shows the process of

Find the coordinates of a charge

Shows the coordinates (x,y) of the charge.