A solar cell assembly, including an electric-optically transducing layer, an electrically conducting layer, and an electrically insulating layer positioned between the electric-optically transducing layer and the electrically conducting layer. A diffusion model for the image segment is determined. The present invention is useful as a pill or series of pills that can be formulated and spotted to a particular formation zone. The separators and the membrane-electrode assemblies, stacked in the guide box, are heated and compressed by a press and heaters to obtain a unitized fuel cell stack. The gripping tools preferably incorporate force sensors which are used to determine overbends needed to get the desired final shape of the archwire.