One or more techniques are provided for identifying a period of minimal motion for an organ of interest, such as the heart or lungs. The plurality of electrodes may be supported on the first layer of material, and are preferably incorporated in andor project from the second layer of material. A semi-rigid offset portion with threaded ends is provided, with an adaptor having a threaded portion to couple to the threaded ends and a slip fitting to couple to the mounting post adaptor. Preferably, the root-tip-trapping region will form between and {fraction } of the sidewall, most preferably between and of the sidewall. The length of the assemblies can be extended without actuating the jack mechanisms to adjust the frame to nearly fit a space between two surfaces. Preferably, the method further includes the step of: constructing a user profile having at least one user characteristic for users of the ad survey.