A method for reducing the damage to a structure caused by an earthquake namely,using laminated rubber for seismic isolation is proposed,and the vibration characteristics of the rubber(which minimizes the seismic respo...A method for reducing the damage to a structure caused by an earthquake namely,using laminated rubber for seismic isolation is proposed,and the vibration characteristics of the rubber(which minimizes the seismic response of the structure during an earthquake)is optimized.A method called“Equivalent Linear System using Restoring Force Model of Power Function Type”(PFT-ELS)is applied to nonlinear vibration analysis of the rubber.In that analysis,a building with 15 layers of the laminated rubber is modeled.The seismic response of the building is analyzed,and the usefulness of the laminated rubber is demonstrated by comparing the seismic responses in the cases with and without the laminated rubber.In addition,the hysteresis restoring-force characteristic of the laminated rubber,which minimizes the seismic response of the building,was optimized by using a genetic algorithm(GA).Based on these results,the optimum restoring-force characteristic for different earthquakes was determined.As a result,it was clarified that the developed optimization method can determine the vibration characteristics of the laminated rubber for minimizing the damage to the structure in the design phase.展开更多
Tetragonal zirconia polycrystals containing 3 mol% yttria (3Y-TZP), which show Superplasticity at high temperatures, were irradiated using 130 MeV Zr+" ions in the TANDEM accelerator facility at Tokai Research Es...Tetragonal zirconia polycrystals containing 3 mol% yttria (3Y-TZP), which show Superplasticity at high temperatures, were irradiated using 130 MeV Zr+" ions in the TANDEM accelerator facility at Tokai Research Establishment, JAERI. The irradiation induced atomic displacement damage was analyzed by TRIM code. Changes in the mechanical properties and fracture behavior caused by the ion irradiation and the effects of subsequent annealing were studied. The distribution of micro-indentation depth as a function of the indentation position from the irradiated surface to the specimen interior was also examined. The occurrence of compressive residual stresses and increases in hardness and fracture toughness were found in the as-irradiated surface region of the specimen. The subsequent annealing revealed that these quantities were decreased gradually with raising the annealing temperature. Probable causes of the generation of the residual stress and the changes in mechanical properties and fracture mode due to the irradiation are discussed.展开更多
1 Results Transition metal-catalyzed [2+2+2] cycloaddition is one of the most efficient protocols for the construction of six-membered ring system.Our group has comprehensively studied various types of highly enantios...1 Results Transition metal-catalyzed [2+2+2] cycloaddition is one of the most efficient protocols for the construction of six-membered ring system.Our group has comprehensively studied various types of highly enantioselective [2+2+2] cycloaddition for the synthesis of chiral cycloadducts; we already reported an iridium-catalyzed intermolecular [2+2+2] cycloaddition between α,ω-diynes,having various tethers and substituents on the alkyne termini,and monoalkynes,possessing oxygen or/and nitrogen functiona...展开更多
文摘A method for reducing the damage to a structure caused by an earthquake namely,using laminated rubber for seismic isolation is proposed,and the vibration characteristics of the rubber(which minimizes the seismic response of the structure during an earthquake)is optimized.A method called“Equivalent Linear System using Restoring Force Model of Power Function Type”(PFT-ELS)is applied to nonlinear vibration analysis of the rubber.In that analysis,a building with 15 layers of the laminated rubber is modeled.The seismic response of the building is analyzed,and the usefulness of the laminated rubber is demonstrated by comparing the seismic responses in the cases with and without the laminated rubber.In addition,the hysteresis restoring-force characteristic of the laminated rubber,which minimizes the seismic response of the building,was optimized by using a genetic algorithm(GA).Based on these results,the optimum restoring-force characteristic for different earthquakes was determined.As a result,it was clarified that the developed optimization method can determine the vibration characteristics of the laminated rubber for minimizing the damage to the structure in the design phase.
文摘Tetragonal zirconia polycrystals containing 3 mol% yttria (3Y-TZP), which show Superplasticity at high temperatures, were irradiated using 130 MeV Zr+" ions in the TANDEM accelerator facility at Tokai Research Establishment, JAERI. The irradiation induced atomic displacement damage was analyzed by TRIM code. Changes in the mechanical properties and fracture behavior caused by the ion irradiation and the effects of subsequent annealing were studied. The distribution of micro-indentation depth as a function of the indentation position from the irradiated surface to the specimen interior was also examined. The occurrence of compressive residual stresses and increases in hardness and fracture toughness were found in the as-irradiated surface region of the specimen. The subsequent annealing revealed that these quantities were decreased gradually with raising the annealing temperature. Probable causes of the generation of the residual stress and the changes in mechanical properties and fracture mode due to the irradiation are discussed.
文摘1 Results Transition metal-catalyzed [2+2+2] cycloaddition is one of the most efficient protocols for the construction of six-membered ring system.Our group has comprehensively studied various types of highly enantioselective [2+2+2] cycloaddition for the synthesis of chiral cycloadducts; we already reported an iridium-catalyzed intermolecular [2+2+2] cycloaddition between α,ω-diynes,having various tethers and substituents on the alkyne termini,and monoalkynes,possessing oxygen or/and nitrogen functiona...