Abstract: A porous body design method using a computer causes the computer to execute, a plurality of times, a characteristic prediction/calculation process of predicting or calculating characteristics of a porous body having a predetermined three-dimensional structure, an evaluation process of evaluating the characteristics of the porous body predicted or calculated by the characteristic prediction/calculation process, and an optimization process of changing connectivity between pores in the three-dimensional structure to search for an optimal connectivity, in which the three-dimensional structure of the porous body is determined on the basis of evaluation results of the characteristics of the porous body by the evaluation process.

Abstract: A porous body design method using a computer causes the computer to execute, a plurality of times, a structure generation process of virtually generating a three-dimensional structure of a porous body on the computer on the basis of generation parameter values for generating the porous body, a characteristic prediction/calculation process of predicting or calculating the characteristics of the porous body having the three-dimensional structure generated by the structure generation process, an evaluation process of evaluating the characteristics of the porous body predicted or calculated by the characteristic prediction/calculation process, and an optimization process of changing the generation parameter values to search for optimal generation parameter values, in which the three-dimensional structure of the porous body is determined on the basis of evaluation results of the characteristics of the porous body obtained by the evaluation process.

Abstract: A vacuum pump comprises: a rotor having multiple stages of rotor blades and a rotor cylindrical portion; a stator having multiple stages of stator blades and a stator cylindrical portion; a base housing the rotor and the stator; and a cover member configured to cover an inner wall portion of the base forming an internal space positioned on a gas-discharge downstream side with respect to gas-discharge-downstream-side end portions of the rotor cylindrical portion and the stator cylindrical portion. An inner peripheral side end of the cover member extends from the internal space to a position overlapping with an inner peripheral surface of the rotor cylindrical portion.

Abstract: A vacuum pump comprises: a rotor cylindrical portion; a motor configured to rotate the rotor cylindrical portion; a stator cylindrical portion, the rotor cylindrical portion and the stator cylindrical portion together forming a screw groove pump; a base housing the rotor cylindrical portion and the stator cylindrical portion; a heater configured to heat the base or the stator cylindrical portion; a cooling device attached to the base; and a cover member arranged at an outer peripheral side of the stator cylindrical portion and an outer peripheral side of the base, covering the base through an air insulating layer, and contacting the cooling device.

Abstract: A vacuum pump comprises: a rotor cylindrical portion; a motor configured to rotate the rotor cylindrical portion; a stator cylindrical portion, the rotor cylindrical portion and the stator cylindrical portion together forming a screw groove pump; a base housing the rotor cylindrical portion and the stator cylindrical portion; a heater configured to heat the base or the stator cylindrical portion; a cooling device attached to the base; and a cover member arranged at an outer peripheral side of the stator cylindrical portion and an outer peripheral side of the base, covering the base through an air insulating layer, and contacting the cooling device.

Abstract: A vacuum pump comprises: a rotor having multiple stages of rotor blades and a rotor cylindrical portion; a stator having multiple stages of stator blades and a stator cylindrical portion; a base housing the rotor and the stator; and a cover member configured to cover an inner wall portion of the base forming an internal space positioned on a gas-discharge downstream side with respect to gas-discharge-downstream-side end portions of the rotor cylindrical portion and the stator cylindrical portion. An inner peripheral side end of the cover member extends from the internal space to a position overlapping with an inner peripheral surface of the rotor cylindrical portion.

Abstract: A turbo-molecular pump comprises: multiple stages of rotor blades formed with multiple blades and provided in a pump axial direction; and multiple stages of stator blades provided with multiple blades, the multiple stages of the rotor blades and the multiple stages of the stator blades being alternately arranged in the pump axial direction. Each stage of the stator blade includes multiple divided stator blades, and a clearance is formed at a portion where the multiple divided stator blades face each other, and circumferential phases of the clearances of adjacent ones of the stages of the stator blades in the pump axial direction are shifted from each other.

Abstract: A forgery prevention medium includes a volume hologram layer on which an interference pattern is recorded after being exposed to an emitted laser beam; a digital watermarking information layer that can be interpreted by emitting a light beam with a predetermined wavelength; and an adherend that has the digital watermarking information layer and is attached to the volume hologram layer, wherein the information layer is of a different color from the volume hologram layer.

Abstract: A forgery prevention medium includes a volume hologram layer on which an interference pattern is recorded after being exposed to an emitted laser beam; a digital watermarking information layer that can be interpreted by emitting a light beam with a predetermined wavelength; and an adherend that has the digital watermarking information layer and is attached to the volume hologram layer, wherein the information layer is of a different color from the volume hologram layer.

Abstract: A forgery prevention medium includes a volume hologram layer on which an interference pattern is recorded after being exposed to at least an emitted laser beam; a digital watermarking information layer on which digital watermarking information is recorded; and a substrate film, and the information recorded on the digital watermarking information layer is interpreted by emitting a light beam that is different in one or more of the characteristics, incidence direction, incidence angle and incidence wavelength, from a hologram reproduction illumination beam used to reproduce an image recorded on the volume hologram layer.