An asymmetrically programmed memory material is described for use as a rectifying element for driving symmetric or substantially symmetric resistive memory elements in a crosspoint memory architecture. A prompt is generated for presentation by the mobile device for a destination point within the premise. Further implementations include a first anchoring branch member extending from the anchoring trunk member. Nonmetallic pins may be used to secure the cable rack arms to the stanchions. If X is not equal to 1, an error condition exists and an amended time t is calculated based on the rate of change X.