面向成本-收益好的无标度耦合网络构建方法

较大平均路径长度的网络会带来较大的网络延迟, 难以支持时间敏感业务与应用. 通过增加连接可以降低源和目的节点之间的跳数, 进而降低网络平均延迟, 使得更加快速地传播信息, 但是增加连接的同时也增加了网络构建成本. 分层网络是研究网络耦合的一个有效方法, 但目前网络构建过程中将每层网络分别处理并认为每层网络之间没有强相关性. 本文提出了一种面向成本-收益的无标度网络动态构建方法. 此方法将网络分为多层, 基于连续论在高层网络中添加连接, 使得网络演化为无标度网络. 此连续过程包括节点度增加过程和局部网络半径增长两个连续过程, 在增加连接的过程中引入表征网络构建成本和收益的成本-收益指标. 模拟结果表明引入成本-收益指标的无标度耦合网络构建方法能够在合理范围内有效降低网络平均路径长度, 提升网络性能, 并且本文给出了耦合网络的动态业务性能, 通过调整高层网络避免网络拥塞.     

精确计算在π~0重整化链图传播下p→p′微分截面

本文采用中性介子π0与核子N-反核子U-强相互作用的Lorentz不变耦合模型,对质子反质子在中性介子π0重整化链图传播下的散射微分截面,作了严格解析计算后获得了"精确"理论结果;进而,又对该计算结果与π0树图传播下的微分截面作了对比分析,获得了相关辐射修正的重要结果.这对于深入研究质子摊贩质子在高、中、低能区中的弹性碰撞及其描述强相互作用的Lorentz不变耦合模型理论,都将提供某些值得借鉴与参考的理论研究价值.     

A field method for integrating the equations of motion of mechanico--electrical coupling dynamical systems

A field method for integrating the equations of motion for mechanico-electrical coupling dynamical systems is studied. Two examples in mechanico-electrical engineering are given to illustrate this method.     

磁瓶式光电子能谱和速度成像光电子能谱对APS-(A=C14H10,蒽)的研究:电子结构,APS·的自旋轨道耦合和APS-的自旋偶极态

Gaseous dibenzo-7-phosphanorbornadiene P-sulfide anions APS^-(A=C₁₄H₁₀ or anthracene) were generated via electrospray ionization, and characterized by magnetic-bottle photoelectron spectroscopy, velocity-map imaging (VMI) photoelectron spectroscopy, and quantum chemical calculations. The electron affinity (EA) and spin-orbit (SO) splitting of the APS^· radical are determined from the photoelectron spectra and Franck-Condon factor simulations to be EA=(2.62±0.05) eV and SO splitting=(43±7) meV. VMI photoelectron images show strong and sharp peaks near the detachment threshold with an identical electron kinetic energy (eKE) of 17.9 meV at three different detachment wavelengths, which are therefore assigned to autodetachment from dipole-bound anion states. The B3LYP/6-31++G(d,p) calculations indicate APS^· has a dipole moment of 3.31 Debye, large enough to support a dipole-bound electron.     

非线性函数耦合的Chen吸引子网络的混沌同步

利用非对称非线性函数耦合混沌同步方法,讨论了Chen吸引子的混沌同步问题,数值模拟分析初始值和耦合强度因子的选择对于实现混沌同步的影响. 将非对称非线性函数耦合同步方法进一步推广发展到完全连接网络和由星形子网络构成的复杂大网络混沌同步的研究中. 提供了确定网络中神经元之间混沌同步状态稳定性的误差发展方程,并讨论各个耦合强度因子对网络同步稳定性过程的影响,给出了相应的稳定性范围. 通过数值模拟证明利用非线性函数作为耦合函数,实现完全连接网络、星形子网络构成大网络的混沌同步是有效的. 可以预测在网络的混沌同步 关键词： 非线性耦合函数 Chen吸引子 混沌同步 网络     

Co1-xNixSb3-ySey热电输运中晶界和点缺陷的耦合散射效应

结合机械合金化与放电等离子烧结工艺制备了Ni和Se共掺的细晶方钴矿化合物Co_1-xNi_xSb_3-ySe_y,研究了晶界和点缺陷的耦合散射效应对CoSb₃热电输运特性的影响.通过Ni掺杂优化载流子浓度提高功率因子.在x=0.1时,功率因子达到最大值1750μWm^-1K^-2(450℃),是没有掺Ni试样的两倍.晶界和点缺陷的耦合散射机理使晶格热导率急剧下降,其中Co_0.9Ni_0.1Sb_2.85Se_0.15的室温晶格热导率降低至1.67Wm^-1K^-1,接近目前单填充效应所能达到的最低值1.6Wm^-1K^-1,其热电优值ZT在450℃时达到最大值0.53.将Callaway-Von Baeyer点缺陷散射模型嵌入到Nan-Birringer有效介质理论模型,对晶界散射和点缺陷散射的耦合效应对热导率的影响进行了定量分析,模型计算与实验结果符合.理论模型计算表明,当晶粒尺寸下降到50nm同时掺杂引入点缺陷散射后,Co_0.9Ni_0.1Sb_2.85Se_0.15的晶格热导率下降到0.8Wm^-1K^-1. 关键词： 3')" href="#">CoSb₃ Ni和Se掺杂 热电性能 耦合散射效应     

间氟溴苯分子240 nm紫外光解动力学

The photodissociation dynamics of m-bromofluorobenzene has been experimentally investigated at around 240 nm using the DC-slice velocity map imaging technique. The kinetic energy release spectra and the recoiling angular distributions of fragmented Br(²P_3/2) and Br(²P_1/2) atoms from photodissociation of m-bromofluorobenzene have been measured at different photolysis wavelengths around 240 nm. The experimental results indicate that two dissociation pathways via (pre-)dissociation of the two low-lying ¹ππ^* excited states dominate the production process of the ground state Br(²P_3/2) atoms. Because of the weak spin-orbit coupling effect among the low-lying triplet and singlet states, the spin-orbit excited Br(²P_1/2) atoms are mainly produced via singlet-triplet state coupling in the dissociation step. The similarity between the present results and that recently reported for o-bromofluorobenzene indicates that the substitution position of the fluorine atom does not significantly affect the UV photodissociation dynamics of bromofluorobenzenes.     

相对论平均场理论对∧,Ξ和∑超核的研究(英文)

基于相对论平均场理论,系统地研究了单∧,Ξ和∑超核,超子-核子相互作用通过拟合实验数据以及参照之前理论工作来确定。以16O为核芯,通过加入不同类型超子（∧,Ξ0,-和∑+,0,-）,比较了超子的平均势场和单粒子能级,并研究了对核芯的杂质效应。整体上看,∧和Ξ0超子在大块性质上类似;Ξ0超子平均势场最浅;库仑相互作用对于带电超子Ξ-,∑+和∑-非常重要。作为杂质,原子核中加入超子会使整个体系更束缚。然而,不同超子对原子核的半径有不同效应。此外,讨论了ωYY张量耦合,发现其对超子的能级劈裂有显著影响,甚至导致Ξ超子中出现能级反转现象。Single ∧, Ξ, and ∑ hypernuclei are systematically studied within the framework of relativistic mean-field (RMF) model with YN interactions being constrained according to the experimental data and previous theoretical efforts. By adding a hyperon to 16O, the mean-field potentials and single-particle levels for hyperons (∧, Ξ0,-, and ∑+,0,-) are compared and the impurity effects on the nuclear core are examined. In general, the ∧ and ∑0 hyperons show similar behaviors in bulk properties since both of them are electroneutral and with similar coupling constants; Ξ0 hyperon owns the shallowest mean-field potential well; and Coulomb interactions play vital roles in the charged Ξ-, ∑-, and ∑+ hyperons. As an impurity, the intruded single-hyperon makes the nuclear system more bound in most cases due to the attractive NY interaction. However, very different effects on the nucleon radii are observed for different hyperons. Besides, the effects of the ωYY tensor couplings on the spin-orbit splitting are discussed, and remarkable influences are found which even change the level ordering of Ξ hyperon.     

超声分子束注入模型与流体输运程序的耦合

将超声分子束注入模型加入到流体输运程序ONETWO 中,为ONETWO 程序提供了重要的粒子源和电子、离子热源项。在ONETWO 程序物理模型中加入超声分子束注入模型,修改TPSMBI 程序并将其耦合到 ONETWO 程序中。运用耦合后的ONETWO 程序模拟研究了喷气法与超声分子束注入产生的源项。将超声分子束注入模型加入到ONETWO 程序中不仅可以为相关的实验分析提供一种重要的工具,也可为未来装置(如中国聚变工程实验堆)的物理设计提供重要的粒子和能量源信息。