The algorithm is divided into two steps. The first step pre-locates the blank by aligning its centre of gravity and approximate normal vector with those of destination surfaces, with largest overlap of projections...The algorithm is divided into two steps. The first step pre-locates the blank by aligning its centre of gravity and approximate normal vector with those of destination surfaces, with largest overlap of projections of two objects on a plane perpendicular to the normal vector. The second step is optimizing an objective function by means of gradient-simulated annealing algorithm to get the best matching of a set of distributed points on the blank and destination surfaces. An example for machining hydroelectric turbine blades is given to verify the effectiveness of algorithm.展开更多
Global seismicity catalogs are sufficient for characterizing double seismic zones （DSZs） in subducting slab and facilitate to estimate layer separation without inconsistent uncertainties as local catalogs. Previous ...Global seismicity catalogs are sufficient for characterizing double seismic zones （DSZs） in subducting slab and facilitate to estimate layer separation without inconsistent uncertainties as local catalogs. Previous studies have shown the correlation between DSZs layer separation and plate age while correlation for those younger than -60 Ma is suspicious. The lacking of DSZs with layer separation less than 10 km further makes it difficult to precisely estimate such correlation. Thus, we incorporate eight DSZs data determined through local seismicity into globally-determined dataset and reexamine such correlation. The best fitting results show that both a linear model and a square root of plate age can mathematically fit the layer separation well. However, it is difficult to distinguish these two models when plate age is greater than -20 Ma since their difference is less than 2 km. However, if extrapolation is possible, both models should provide physical information that DSZs will not form if there is no subducting lithosphere. As a result, the DSZs cannot be produced until the oceanic lithospheric age becomes greater than 0.9 Ma in the square root model while the linear model gives a misleading result. As such the square root model demonstrates the relationship physically better than the linear one, it still needs further test in the future with more available data, nevertheless, our study might also provide evidence for the suggestion that the plate age is a primary control factor of the DSZs geometry as well as the subducting process which disregards any local tectonic stresses.展开更多
In this research work, the upward transition probabilities for the transition levels, 0<sup>+</sup> → 2<sup>+</sup>, 2<sup>+</sup> → 4<sup>+</sup>, 4<sup>+</s...In this research work, the upward transition probabilities for the transition levels, 0<sup>+</sup> → 2<sup>+</sup>, 2<sup>+</sup> → 4<sup>+</sup>, 4<sup>+</sup> → 6<sup>+</sup> and 6<sup>+</sup> → 8<sup>+</sup> levels of even-even neutron rich <sup>104-114</sup>Ru isotopes have been calculated by using the Global Best Fit (GBF) method. In addition, the associated parameters such as, Quadrupole moment and Deformation parameter of even-even <sup>104-114</sup>Ru have been calculated. The dependency of these nuclear parameters shows the nuclear magic number tendency.展开更多
文摘The algorithm is divided into two steps. The first step pre-locates the blank by aligning its centre of gravity and approximate normal vector with those of destination surfaces, with largest overlap of projections of two objects on a plane perpendicular to the normal vector. The second step is optimizing an objective function by means of gradient-simulated annealing algorithm to get the best matching of a set of distributed points on the blank and destination surfaces. An example for machining hydroelectric turbine blades is given to verify the effectiveness of algorithm.
基金supported by the National Natural Science Foundation of China(grant Nos.40874047 and 40574047)
文摘Global seismicity catalogs are sufficient for characterizing double seismic zones （DSZs） in subducting slab and facilitate to estimate layer separation without inconsistent uncertainties as local catalogs. Previous studies have shown the correlation between DSZs layer separation and plate age while correlation for those younger than -60 Ma is suspicious. The lacking of DSZs with layer separation less than 10 km further makes it difficult to precisely estimate such correlation. Thus, we incorporate eight DSZs data determined through local seismicity into globally-determined dataset and reexamine such correlation. The best fitting results show that both a linear model and a square root of plate age can mathematically fit the layer separation well. However, it is difficult to distinguish these two models when plate age is greater than -20 Ma since their difference is less than 2 km. However, if extrapolation is possible, both models should provide physical information that DSZs will not form if there is no subducting lithosphere. As a result, the DSZs cannot be produced until the oceanic lithospheric age becomes greater than 0.9 Ma in the square root model while the linear model gives a misleading result. As such the square root model demonstrates the relationship physically better than the linear one, it still needs further test in the future with more available data, nevertheless, our study might also provide evidence for the suggestion that the plate age is a primary control factor of the DSZs geometry as well as the subducting process which disregards any local tectonic stresses.
文摘In this research work, the upward transition probabilities for the transition levels, 0<sup>+</sup> → 2<sup>+</sup>, 2<sup>+</sup> → 4<sup>+</sup>, 4<sup>+</sup> → 6<sup>+</sup> and 6<sup>+</sup> → 8<sup>+</sup> levels of even-even neutron rich <sup>104-114</sup>Ru isotopes have been calculated by using the Global Best Fit (GBF) method. In addition, the associated parameters such as, Quadrupole moment and Deformation parameter of even-even <sup>104-114</sup>Ru have been calculated. The dependency of these nuclear parameters shows the nuclear magic number tendency.
