The present invention relates generally to a software architecture for simulation of physical entities. The weight percentage of the lithium iron phosphate is between 1 wt % and 49 wt %, and the weight percentage of the lithium iron phosphate is based on the total weight of the polyimide film. A barrier film is formed on the surfaces of the silicon plugs, and in the holes a dielectric is formed to form lower electrodes of the capacitor elements and an upper electrode therefor. In exemplary embodiment, handles are bowed with upper portions positioned substantially above said cylinder to enable user sitting on said cylinder to reach upward and grasp handle upper portions, and frame includes transversely spaced posts, handles include portions extending downward to engage posts.