iffness coefficient parameter</p><p><b>References</b>:</p><div><ul><li><a href="https://doi.org/10.1122/1.549893">O.R. Walton and R.L. Braun. Viscosity, granular temperature, and stress calculations for shearing assemblies of inelastic, frictional disks, <i>J. Rheol.</i>, 30:949, 1986</a> (proposal)</li></ul></div><pre class="codeinput"><span class="keyword">classdef</span> ContactForceN_ElastoPlasticLinear &lt; ContactForceN
</pre><h2 id="2">Public properties</h2><pre class="codeinput">    properties (SetA