Abstract: A system determination apparatus includes: a calculation unit configured to calculate a variation coefficient representing a degree of variation of traffic and an average traffic amount corresponding to a plurality of days using traffic data of a network apparatus corresponding to the plurality of days; and a determination unit configured to determine a system of the network apparatus using a density of a data group representing a relationship between the variation coefficient and the average traffic amount corresponding to the plurality of days, and the determination unit determines the network apparatus to be a non-operation system in a case where a density of the data group is equal to or higher than a first threshold and determines the network apparatus to be an operation system in a case where the density of the data group is lower than the first threshold.

Abstract: Provided are turbine blades and a gas turbine capable of damping the vibrations caused by an excitation force and facilitating mounting/disassembly. Included are a shroud portion disposed at an end portion of an airfoil portion; a holder casing that can slide relative to the shroud portion, that can also be attached thereto/detached therefrom, and that forms a space with the shroud portion therebetween; and an elastic portion that is disposed in the space, that biases the shroud portion in a direction that separates it from the holder casing, and is disposed in a movable manner relative to the shroud portion; and a pressing portion that is disposed between the elastic portion and the holder casing and that can be moved toward and away from the shroud portion.

Abstract: An inner shroud portion and an outer shroud portion dividedly formed per stationary blade are formed integrally with each stationary blade. A plurality of the stationary blades adjacent to each other in a circumferential direction are coupled together by a band member at the outer shroud portions. The inner shroud portions are held between seal holders which are formed as two divided members in the flowing direction of a working fluid, which are fastened by a bolt, and which have a length corresponding to the plurality of the stationary blades. The plurality of stationary blades, the inner and outer shroud portions, the band member, and the seal holders assembled in this manner constitute a unit. A plurality of the units are connected in the circumferential direction to constitute a stationary blade ring of an axial compressor.

Abstract: Provided are turbine blades and a gas turbine capable of damping the vibrations caused by an excitation force and facilitating mounting/disassembly. Included are a shroud portion disposed at an end portion of an airfoil portion; a holder casing that can slide relative to the shroud portion, that can also be attached thereto/detached therefrom, and that forms a space with the shroud portion therebetween; and an elastic portion that is disposed in the space, that biases the shroud portion in a direction that separates it from the holder casing, and is disposed in a movable manner relative to the shroud portion; and a pressing portion that is disposed between the elastic portion and the holder casing and that can be moved toward and away from the shroud portion.

Abstract: An inner shroud portion and an outer shroud portion dividedly formed per stationary blade are formed integrally with each stationary blade. A plurality of the stationary blades adjacent to each other in a circumferential direction are coupled together by a band member at the outer shroud portions. The inner shroud portions are held between seal holders which are formed as two divided members in the flowing direction of a working fluid, which are fastened by a bolt, and which have a length corresponding to the plurality of the stationary blades. The plurality of stationary blades, the inner and outer shroud portions, the band member, and the seal holders assembled in this manner constitute a unit. A plurality of the units are connected in the circumferential direction to constitute a stationary blade ring of an axial compressor.

Abstract: Gas turbine starting method is improved to start operation with bleed valves being first throttled, then fully opened on the way and then fully closed at 90% speed, thereby fluid unstableness phenomenon is suppressed and starter motor power is reduced. While inlet guide vane (11) and variable stator vanes (C1 to C5) are set to predetermined opening from starting to rated speed, bleed valves (1, 2, 3) are set to predetermined opening until 52% speed for the bleed valve (1) and until 51% speed each for the bleed valves (2, 3), then the bleed valves (1, 2, 3) are fully opened until the speed exceeds 90%, when they are fully closed for rated operation. In the prior art, starting operation is done with bleed valves being first fully opened until the speed is elevated to 90% and then fully closed, but in the present invention, air discharged into ambient air in vain can be reduced and thereby starter motor power can be also reduced.