Abstract: A RF signal beam transmission enhancement board comprising: a substrate having at least one substrate surface; at least one elemental-featuring layer disposed on the substrate surface and including a plurality of elemental-featuring elements; and at least one index-matching layer arranged to cover the elemental-featuring elements and the substrate surface. The plurality of elemental-featuring elements has a pattern arrangement with a pattern resolution Rp given by Rp = ? N , where ? is a wavelength of a signal beam to be transmitted and N is an integer ranging from 1 to 10 such that the index-matching layer can work with the elemental-featuring elements to form an elemental-surface for minimizing reflection of a signal beam to be transmitted through the signal beam transmission enhancement board.

Abstract: An electric wheelchair comprising a movable seat part (1), a body part (2) served as a support for the seat part, a seat adjustment mechanism (3) arranged under the seat part, a bottom part (4), and a crawler moving mechanism (5). The crawler moving mechanism (5) comprises two sets of crawlers arranged respectively at both sides underneath the bottom part, and each of which comprises a front crawler and a rear crawler. The bottom part (4) is comprised of a front portion and a rear portion, which are movably connected with a coupling arrangement and capable of deflection with respect to each other. The crawler moving mechanism (5) further comprises movable stretching crawlers arranged respectively at outside of the front crawler, and fixed stair-climbing crawlers arranged respectively at outside of the rear crawler, wherein a free end of the fixed stair-climbing crawler forms a specific angle relative to the rear crawler.

Abstract: An electric wheelchair comprising a movable seat part (1), a body part (2) served as a support for the seat part, a seat adjustment mechanism (3) arranged under the seat part, a bottom part (4), and a crawler moving mechanism (5). The crawler moving mechanism (5) comprises two sets of crawlers arranged respectively at both sides underneath the bottom part, and each of which comprises a front crawler and a rear crawler. The bottom part (4) is comprised of a front portion and a rear portion, which are movably connected with a coupling arrangement and capable of deflection with respect to each other. The crawler moving mechanism (5) further comprises movable stretching crawlers arranged respectively at outside of the front crawler, and fixed stair-climbing crawlers arranged respectively at outside of the rear crawler, wherein a free end of the fixed stair-climbing crawler forms a specific angle relative to the rear crawler.

Abstract: An integrated test circuit for a silicon on insulator circuit structure is formed on the same wafer as the circuit structure. The wafer includes an input circuit coupled to the silicon on insulator circuit structure which generates a drive signal for operating the silicon on insulator circuit structure and an output circuit which processes a response signal from the circuit structure to generate an output signal representing certain characteristics of the silicon on insulator circuit structure.