A method is disclosed to form a reliable silicon nitride spacer between the lower edges of the floating gate and the control gate of a split-gate flash memory cell. The method is applicable for a flash memory having predefined erase-write blocks and write-read blocks, for enhancing the tampering proof characteristics of the flash memory. An improved heat exchange system includes heat exchange elements within the heat exchangers comprised of hybrid externally finned elements, smooth interior stainless steel tubes thermally bonded within the externally finned elements, the tubes containing vortex generators. The wireless device may adjust the propagation model based on the received wireless signals and the arrangement-based distance values, and may generate adjusted distance values using the adjusted propagation model. A stop on telescopic arm link shaft further allows the golfer to adjust the maximum amount of angle change desired during a golf swing. The connection unit may be heated to reflow and fuse the solder portions to the contact termination, thereby constructing an array.