Abstract: An operation assistance system for a small watercraft includes: a position specification unit that specifies an abnormality occurrence position, which is a position where an abnormality has occurred, when the abnormality has occurred in a small watercraft; a transmission unit that transmits information on the abnormality occurrence position specified by the position specification unit; and a processing circuit, in which the processing circuit includes a storage unit that stores information on the abnormality occurrence position transmitted from the transmission unit, and an information provision unit that creates predetermined operation assistance information based on information on the abnormality occurrence position stored in the storage unit and transmits the created operation assistance information.

Abstract: Optical-disk stamper that prevents mold-release defects caused by mold-release irregularities that occur when the mold is opened while improving transferability during disk molding to enable the manufacture of high-quality optical disks at a favorable yield rate. On one side of a stamper body (1), a molding surface (2) furnished when bumps (3) for imprinting pits into an optical disk is formed. The molding surface, including the bumps, is formed of a polymer resin whose thermal diffusivity is 0.01 m2/h or under. More preferably the molding surface is formed of a poorly heat-conducting phenolic resin whose thermal diffusivity is between 0.0004 and 0.001 m2/h, suppressing heat diffusion from the molten resin toward the stamper during the disk molding process and nullifying rapid cooling and local hardening of the resin.

Abstract: Continuous DNA-amplification method and apparatus. Reaction mixture containing reagent solution and DNA fragments serving as templates is continuously temperature-processed by heat-exchange fluids whose temperatures differ, enabling successive DNA amplification reactions to be carried out efficaciously in large volume. Apparatus has a reaction-mixture tank, isothermal denaturing, annealing and elongation tanks, a recirculation path that circuits the isothermal tanks, and a pump that works to feed reaction mixture within the recirculation path unidirectionally through it. The reaction mixture, transferred from tank to tank by the pump, is maintained at prescribed reaction temperatures in the isothermal tanks. Heat-exchange efficiency is improved compared with batch systems, and the reaction mixture—uniformly, swiftly put into prescribed temperature states—can be amplification-reacted under ideal conditions, enabling quantum improvement in the amplification efficiency.

Abstract: Optical-disk stamper that prevents mold-release defects caused by mold-release irregularities that occur when the mold is op,ened while improving transferability during disk molding to enable the manufacture of high-quality optical disks at a favorable yield rate. On one side of a stamper body (1), a molding surface (2) furnished with bumps (3) for imprinting pits into an optical disk is formed. The molding surface, including the bumps, is formed of a polymer resin whose thermal diffusivity is 0.01 m2/h or under. More preferably the molding surface is formed of a poorly heat-conducting phenolic resin whose thermal diffusivity is between 0.0004 and 0.001 m2/h, suppressing heat diffusion from the molten resin toward the stamper during the disk molding process and nullifying rapid cooling and local hardening of the resin.

Abstract: The axial power distribution of a nuclear reactor in a region of high burn-up degrees should desirably be flat. In consideration of the fact that void coefficients have a distribution in the axial direction, a mean infinite multiplication factor in an axially upper region of a reactor core is made lower than a mean infinite multiplication factor in a lower region. Especially, this becomes possible in such a way that a mean enrichment factor of fuel located in the uppr region is made lower than a mean enrichment factor of fuel located in the lower region.

Abstract: The core of a nuclear reactor is constituted by two sorts of fuel assemblies: first fuel assemblies each of which contains both fissile material and gadolinea and second fuel assemblies each of which contains only the fissile material. The ratio of the number of the first fuel assemblies to that of the second fuel assemblies are selected to be 1:3. The enrichment of the fissile material is larger at the upper part of the reactor core than at the lower part of the same. The fuel assembly containing both of the fissile material and the gadolinea includes first fuel rods each of which contain both the fissile material and the gadolinea, and second fuel rods which contains only the fissile material. The number of the first fuel rods and the concentration of gadolinea are substantially in proportion to the power density at positions in the reactor core where the fuel assembly is placed.