A preferred embodiment of the invention is directed to support structures such as spacers used to provide a uniform distance between two layers of a device. The memory card includes a flash memory and a control chip for controlling the flash memory, and the control chip has a voltage regulator, a pad power supplier, a core controller and an output circuit. A second set of programs is stored on a server, with at least one of the first set of programs having a counterpart in the second set of programs. When a pointer has returned to an initial position, the magnetic flux generated in the output coil can reach the detection coil through the magnetic piece, so that a microcomputer can detect the initial position of the pointer. Each modular beamformer may further comprise a plurality of multipliers assigned to the delaying units to generate conditioned signals by adaptively applying weights to the signals output by the plurality of delaying units. The virtual assistants may additionally, or alternatively, interact with each other to carry out tasks for the users, which may be illustrated in conversation user interfaces.