Abstract: A method of manufacturing a positive electrode material has the steps of synthesizing an iron metal in a phosphoric acid solution to form an iron phosphate dispersion solution; adding a vanadium pentoxide (V2O5), a non-ionic surfactant and a carbon source to the iron phosphate dispersion solution; and adding a lithium salt to the iron phosphate dispersion solution and then grinding and dispersing it to produce a positive electrode material. By regulating the timing of the addition of vanadium pentoxide (V2O5), the present invention enables the battery made of the positive electrode material to have the advantage of higher battery performance.

Abstract: The invention discloses a method for transmitting digital contents between devices. First digital contents are modulated into an audio signal in a first device, wherein the first digital contents include contact information and at least one index of at least one second digital content. The audio signal is outputted by at least one audio generator of the first device and then received by at least one audio receiver of a second device. The audio signal is demodulated in the second device to make the second device obtain the first digital contents. The second device obtains the at least one second digital content according to the at least one index of the at least one second digital contents through a wired or wireless communication.

Abstract: A method for diagnosing blades of a wind turbine is provided. The method includes steps of acquiring, via a microphone, an operation sound of the wind turbine when the wind turbine is under operation; transforming the operation sound into a time-frequency spectrum; integrating the time-frequency spectrum over time to generate a marginal spectrum; determining whether any blade of the wind turbine is damaged according to the marginal spectrum and a reference curve.

Abstract: The invention discloses a method for transmitting digital contents between devices. First digital contents are modulated into an audio signal in a first device, wherein the first digital contents include contact information and at least one index of at least one second digital content. The audio signal is outputted by at least one audio generator of the first device and then received by at least one audio receiver of a second device. The audio signal is demodulated in the second device to make the second device obtain the first digital contents. The second device obtains the at least one second digital content according to the at least one index of the at least one second digital contents through a wired or wireless communication.