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11.
<正> Su has recently established the projective theory of space curvesby a purely geometrical method and has shown among other thingsthat the projective invariants of a curve can simply be expressed by cer-tain double ratios.In my former paper I have interpreted the curvatureform by the Von Staudt's double ratios of the tangent of the space curveC at a point infinitely near an ordinary point P with respect to unda-mental tetrahedron of Sannia at P. 相似文献
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The correlation between neutron-to-proton yield ratio (Rnp) and neutron skin thickness (δnp) in neutron-rich projectile induced reactions is investigated within the framework of the Isospin-Dependent Quantum Molecular Dynamics (IQMD) model. The density distribution of the Droplet model is embedded in the initialization of the neutron and proton densities in the present IQMD model. By adjusting the diffuseness parameter of neutron density in the Droplet model for the projectile, the relationship between the neutron skin thickness and the corresponding Rnp is obtained. The results show strong linear correlation between Rnp and δnp for neutron-rich Ca and Ni isotopes. It is suggested that Rnp may be used as an experimental observable to extract δnp for neutron-rich nuclei, which is very interesting in the study of the nuclear structure of exotic nuclei, the equation of state (EOS) of asymmetric nuclear matter and neutron-rich matter in astrophysics, etc. 相似文献
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Investigation of Exotic Structure of the Largely Deformed Nucleus ^23A1 in the Relativistic-Mean-Field Model
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A candidate for proton halo nucleus ^23A1 is investigated based on the constrained calculations in the framework of the de[ormed relativistic mean tield (RMF) model with the NL075 parameter set. It is shown by the constrained calculations that the ground state of ^23A1 has a large deformation that corresponds to the prolate shape. With that large deformation, the non-constrained RMF calculation predicts that there appears an inversion between the 2s1/2 [211] and ld5/2 [202] shells. The valence proton of ^23A] is weakly bound and occupies 2s1/2 [211] and ld5/2 [202] with the weights of 56% and 29%, respectively. The calculated RMS radius for matter is in agreement with the experimental one. It is also predicted that the difference between the proton RMS radius and the neutron one is very large, This suggests that there exists a proton hMo in ^23Al. 相似文献
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AAC是MPEG-4标准的音频编码规范,为了提高音频数据的压缩率,往往忽略了音频中所包含的高频成分,只对低频部分进行编码,因此AAC解码器设计中高频重建技术对提高音频质量起着非常重要的作用.本文论述了高频重建技术的原理,并采用SBR技术,实现了AAC音频编码的高频重建,同时性能评测结果表明所实现的AAC SBR系统满足实际应用的要求. 相似文献
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The isoscaling behaviour is investigated in a frame of isospin-dependent quantum molecular dynamics models. The isotopic yields ratio Y2/Y1 for reactions ^48Ca ^48Ca and ^40 Ca ^4oCa at different entrance channels are simulated and presented, the relationship between the isoscaling parameter and the entrance channel is analysed, the results show that a and β reduce with the rise of incident energies and increase with the impact parameter b, which can be attributed to the temperature varying of the pre-fragments in different entrance channels. The relation of a and symmetry-term coefficient Csym reveals that the chemical potential difference △μ is sensitive to thesymmetry-term coefficient Csym, and raises with the increasing Csym. 相似文献
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随着5G商用的到来,基于5G三大应用场景的业务需求,现有核心网集中式部署不能满足新的需求,网络随业务流向边缘迁移是产业发展趋势。移动边缘计算靠近用户侧部署,能提供更短时延和保护隐私等功能。本文通过分析移动边缘计算面向的重点行业和重点领域等业务发展需求,协同构建客户的业务、无线和局房资源视图,匹配出移动边缘计算部署机房位置及资源储备。 相似文献
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烯酮或乙烯与甲醛环加成协同反应机理的对比研究 总被引:1,自引:0,他引:1
本文研究了烯酮与甲醛, 乙烯与甲醛两个环加成反应的协同过程的过渡态(TS),用能量分解方法对两个过渡态中反应物间的相互作用能的本质做了剖析。通过对比,发现在乙烯与甲的过渡态中反应物的占有轨道间电子的交换排斥作用能比较大, 从而可以说明此反应比乙烯与烯酮间的协同过程难于进行。 相似文献