Abstract: In a turbine rotor in which a rotor material has lower tensile strength than a blade material and the difference in tensile strength between both the materials is large, a strength margin on the blade side is properly distributed to a strength margin on the rotor side with the aim of reducing shear stress in a rotor hook, increasing stiffness of the rotor hook, and reducing peak stress in a rotor neck, to thereby provide a steam turbine rotor and an inverted fir-tree turbine blade in which stress balance is made more appropriate depending on a material strength ratio of the blade material to the rotor material. In the turbine rotor, a rotor radial-direction hook length (Hri) of an i-th rotor hook counting from the outermost circumference of the rotor and a blade radial-direction hook length (Hbi) of an i-th blade hook counting from the outermost circumference of the blade are set to satisfy the relationship of (Hri>Hbi).

Abstract: Minimization of risks to be incurred by a generating plant firm at the time of the firm's non-fulfillment of an agreement for electric power supply which is attributed to an unscheduled shutdown of power generating equipment that supplies electric power to electric power systems. A service center takes an intermediary action for the conclusion of indemnity insurance agreements, in a lump, between a generating plant firm which has power generating equipment and an insurance company, and contracts another indemnity insurance agreement with an electric power company so that a penalty to be incurred at the time of a non-fulfillment of an agreement for electric power supply can be indemnified by the insurance company. Furthermore, the service center subcontracts a maintenance and management service of the power generating equipment, and offers information of operation information and the maintenance status of the power generating equipment to the insurance company for the calculation of insurance premiums.

Abstract: This invention discloses a new semiconductor device having no step type p-i-n juctions but rather has a graded p-i-n juction. The semiconductor device shows a high photoelectric conversion efficiency, and since said device can be produced easily with good reproducibility by a plasma discharge method, it is especially suited for use as a solar battery. An apparatus for the production of said semiconductor device is also disclosed.

Abstract: This invention disclose an amorphous silicon semiconductor film containing at least hydrogen, carbon and oxygen as impurities and the method to produce it. The film is characterized in that the total quantity of carbon and oxygen in said film is at least 0.1 atom %. Since the film has small light absorption coefficient and its optical refractive index is controllable, an excellent window material for solar cell can be provided. Since adherence of the film with a metal electrode as well as with a transparent electrode is sufficient, good reproducibility in making solar cells using the film of this invention as a window material was realized.