A scraper blade for a conveyor may comprise: a blade body having a scraping edge and a base for mounting the scraper blade on a blade mount of a conveyor, wherein the blade body has a plurality of elongated recessed features extending across the rearward side thereof, wherein the elongated recessed features are spaced apart and are generally parallel to the scraping edge. Embodiments of the invention provide for a transmission that is coaxially mounted with the output shafts and the two motorgenerators, which allows for a space-saving design. A source of optical energy is configured to inject optical energy into the optical fiber, and an optical detector is configured to detect a first optical return signal having characteristics that are affected by vibrations of the structural elements. B-number, no longer refers to the subscription networknumber range owner and the old rule \u201cthe number range of the called party reveals the tariff level\u201d is no longer valid. The PIFA becomes smaller by using an electrical resonance length of the feed line, a shape of the feed line, and the open stub and the matching pad, improves the flexibility of the antenna design, and obtains a wider frequency band.