The present invention relates to a novel fulvene compound and a preparation method thereof, and more particularly to a fulvene compound having substituted groups in the 2- and 5-positions, prepared from an unsaturated ketone having a substituted group in the \u03b2-position and a halogen atom in the \u03b1-position, and a preparation method thereof. The engine is constructed and arranged to operate from a stored power source such as batteries to provide extended run times by controlling the power supplied to the electromagnets in a manner that controls heat generation within the electromagnetic coils, thereby increasing coil life. The bioengineered graft prostheses are used for implantation, repair, or use in a mammalian host. The heat sink is used to transmit heat. A method for communicating messages requiring synchronization includes receiving symbols in a modem; analyzing the symbols to identify a primitive synchronization signal; and modifying a physical layer operating parameter of the modem in response to identifying the primitive synchronization signal.