In consideration of the fuzzy constraint boundary and through analysis of structural reliability, a model of structural fuzzy optimum design is established based on reliability for offshore jacket platforms. According...In consideration of the fuzzy constraint boundary and through analysis of structural reliability, a model of structural fuzzy optimum design is established based on reliability for offshore jacket platforms. According to the characteristics of offshore jacket platforms, the tolerance coefficient of the constraint boundary is determined with the fuzzy optimization method. The optimum level cut set lambda*, which is the intersection of the fuzzy constraint set and fuzzy objective set, is determined with the bound search method, and then the fuzzy optimum solution to the fuzzy optimization problem is obtained. The central offshore platform SZ36-1 is designed with the fuzzy optimum model based on reliability; the results are compared with those from deterministic optimum design and fuzzy optimum design. The tendency of design variables in the above three methods and its reasons are analyzed. The results of an example show that the fuzzy optimum design based on reliability is stable and reliable.展开更多
The holographic storage properties of Fe (0.03% (mass fraction) Fe2O3):LiNbO3 doped with Sc at different levels (0, 1%, 2%, 3%) were investigated. The Sc threshold concentration in Fe:LiNbO3 was implied to be ...The holographic storage properties of Fe (0.03% (mass fraction) Fe2O3):LiNbO3 doped with Sc at different levels (0, 1%, 2%, 3%) were investigated. The Sc threshold concentration in Fe:LiNbO3 was implied to be about 3% (mole fraction) because O-H vibration absorption peak of Sc (3%):Fe:LiNbO3 was at 3508 cm^-1, compared with 3484 cm^-1 of crystals with lower Sc doping level. Sc(3%):Fe:LiNbO3 exhibited higher optical damage resistance ability. The threshold intensity (wavelength 488 nm) of Sc (3%):Fe:LiNbO3 was 2.2 ×10^2 W ·cm^-2, two orders of masnitude higher than that of Fe:LiNbO3. Holographic storage properties of the crystals were determined in an extraordinary polarized laser of wavelength 632.8 nm by a two-wave coupling method. It was found that in terms of holographic storage properties, the optimal doping concentration of Sc was 2% (mole fraction) among this crystal series.展开更多
基金This research project was financially supported by the National Natural Science Foundation of China (Grant No. 59895410)
文摘In consideration of the fuzzy constraint boundary and through analysis of structural reliability, a model of structural fuzzy optimum design is established based on reliability for offshore jacket platforms. According to the characteristics of offshore jacket platforms, the tolerance coefficient of the constraint boundary is determined with the fuzzy optimization method. The optimum level cut set lambda*, which is the intersection of the fuzzy constraint set and fuzzy objective set, is determined with the bound search method, and then the fuzzy optimum solution to the fuzzy optimization problem is obtained. The central offshore platform SZ36-1 is designed with the fuzzy optimum model based on reliability; the results are compared with those from deterministic optimum design and fuzzy optimum design. The tendency of design variables in the above three methods and its reasons are analyzed. The results of an example show that the fuzzy optimum design based on reliability is stable and reliable.
基金Project supported by Natural Science Foundation of Heilongjiang Province (E200512)
文摘The holographic storage properties of Fe (0.03% (mass fraction) Fe2O3):LiNbO3 doped with Sc at different levels (0, 1%, 2%, 3%) were investigated. The Sc threshold concentration in Fe:LiNbO3 was implied to be about 3% (mole fraction) because O-H vibration absorption peak of Sc (3%):Fe:LiNbO3 was at 3508 cm^-1, compared with 3484 cm^-1 of crystals with lower Sc doping level. Sc(3%):Fe:LiNbO3 exhibited higher optical damage resistance ability. The threshold intensity (wavelength 488 nm) of Sc (3%):Fe:LiNbO3 was 2.2 ×10^2 W ·cm^-2, two orders of masnitude higher than that of Fe:LiNbO3. Holographic storage properties of the crystals were determined in an extraordinary polarized laser of wavelength 632.8 nm by a two-wave coupling method. It was found that in terms of holographic storage properties, the optimal doping concentration of Sc was 2% (mole fraction) among this crystal series.