用独立元格等效作用量研究三维U(1)格点规范理论的相结构

在格点规范理论中,应用变分累积展开方法,引入独立元格等效作用量,研究了三维U(1)格点规范理论的元格内能,得到连续的内能曲线,与Monte Carlo(MC)数据相符,表明理论是禁闭的.     

Large deviations behavior of counting processes and their inverses

We show, under regularity conditions, that a counting process satisfies a large deviations principle in or the Gärtner-Ellis condition (convergence of the normalized logarithmic moment generating functions) if and only if its inverse process does. We show, again under regularity conditions, that embedded regenerative structure is sufficient for the counting process or its inverse process to have exponential asymptotics, and thus satisfy the Gärtner-Ellis condition. These results help characterize the small-tail asymptotic behavior of steady-state distributions in queueing models, e.g., the waiting time, workload and queue length.     

Expressing a Probability Density Function in Terms of another PDF: A Generalized Gram-Charlier Expansion

An explicit formula relating the probability density function with its cumulants is derived and discussed. A generalization of the Gram-Charlier expansion is presented, allowing to express one PDF in terms of another. The coefficients of this general expansion are explicitly obtained.      

连续相位调制技术的分析与应用

探讨了连续相位调制技术,提出了基于CPM技术的应用实例,任何连续相位调制器均可分解为无记忆调制器和连续相位编码器,该技术具有较高的功率和频谱利用率.采用多元码和CPM调制技术相结合实现的串行级联系统,既降低了CPM系统成本,又提高了系统性能,具有较大的实用价值.     

Methods of Quantum Field Theory in the Physics of Subsurface Solute Transport

The stochastic theory of subsurface solute transport has received stimulus recently from modeling techniques originating in quantum field theory (QFT), resulting in new calculations of the solute macrodispersion tensor that derive from the solving Dyson equation with a subsequent renormalization group analysis. In this paper, we offer a critical evaluation of these techniques as they relate specifically to the derivation of a field-scale advection–dispersion equation. An approximate Dyson equation satisfied by the ensemble-average solute concentration for tracer movement in a heterogeneous porous medium is derived and shown to be equivalent to a truncated cumulant expansion of the standard stochastic partial differential equation which describes the same phenomenon. The full Dyson equation formalism, although exact, is of no importance to the derivation of an improved field-scale advection–dispersion equation. Similarly, renormalization group analysis of the macrodispersion tensor has not yet provided results that go beyond what is available currently from the cumulant expansion approach.     

基于分数间隔的四二阶归一化累积量盲均衡算法

针对目前分数间隔盲均衡算法存在的缺陷,提出了基于分数间隔的四二阶归一化累积量盲均衡算法.先对接收信号进行分数间隔采样,然后利用四二阶归一化累积量将盲均衡算法归结为无约束的极值问题,从而简化了算法,加快了收敛速度,降低了误码率.仿真验证了算法的有效性.     

基于吸收峰混叠的红外混合气体分析方法的研究

针对5种主次吸收峰严重交叠的红外混合气体定量分析问题,提出一种基于高阶累积量分析方法,该方法将重叠的吸收谱线映射到彼此相互分开的四阶累积量空间;在四阶累积量空间中提出一种基于正则理论和最小二乘相结合的支持向量机多维数据建模方法.在小样本下有效地提高了模型的准确度和收敛速度实验结果表明,该方法使系统的引用误差小于4%,因而能满足外场使用的要求.     

Cumulants in the 3-dimensional Ising,O（2） and O（4） spin models

Based on the universal properties of a critical point in different systems and that the QCD phase transitions fall into the same universality classes as the 3-dimensional Ising, O（2） or O（4） spin models, the critical behavior of cumulants and higher cumulant ratios of the order parameter from the three kinds of spin models is studied. We found that all higher cumulant ratios change dramatically the sign near the critical temperature. The qualitative critical behavior of the same order cumulant ratio is consistent in these three models.     

THERMODYNAMIC PROPERTIES OF LADDER-LIKE HEISENBERG SYSTEM

By combining the cumulant expansion method with the double-chain approximation , we study thermodynamic properties of ladder-like He isenberg system. We find the interaction between interchains has different effect in high and low temperature.     

Statistical decomposition of chaotic attractors by the eigenvectors of Oseledec matrix-active and passive information dynamics

Summary Correlated sets of physical variables or coordinates of the equations of motion are extracted from the distribution of eigenvectors of theOseledec matrix. These coordinates characterize the dynamics on the (un-)stable manifolds. The information-theoretic properties of the dynamics on the (un-)stable foliations imply a decomposition of chaos by theactive andpassive coordinates. We introduceinformation consumption in the active dynamics to account for the complicated dynamics on some of the stable manifolds. The information flow direction is transversal to the subspace spanned by the passive coordinates. Its dynamics can beisolated orone-way decorrelated. An example is given to show how these ideas can be applied to better understand the chaotic modal interaction of a nonlinear beam.