首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
1.
在AHP应用中提出了各种各样的标度,在分析比较各种标度后,得出指数标度是核心标度的结论,证明了1-9标度与指数标度不相容,指出许多标度实质上只是指数标度的特例,提出了确定指数标度参数的方法,并指出了应用指数标度时应注意的问题及其解决办法。  相似文献   

2.
李洪云  尹妍妍  王青  王立飞 《物理学报》2015,64(18):180502-180502
利用半经典方法研究了平行电磁场中里德堡氢原子的分形自相似现象. 通过研究平行电磁场中里德堡氢原子的逃逸时间和初始出射角间的关系, 发现了逃逸时间图的自相似结构, 并通过研究与图中冰柱对应的逃逸轨道, 得到了自相似结构和逃逸轨道之间的关系, 发现了该类自相似逃逸轨道满足的规律. 进一步研究了标度能量和标度磁场对体系动力学的影响, 表明标度能量和标度磁场均控制体系的分形自相似结构. 当标度能量或标度磁场比较小时, 没有自相似现象, 随着标度能量或标度磁场的增大, 自相似出现, 体系变复杂.  相似文献   

3.
针对全反射棱镜式激光陀螺标度因数随温度周期性变化的现象,根据矩阵光学方法研究了稳频状态下温度变化对环形激光面积的影响,获得了全反射棱镜式激光陀螺标度因数与稳频电压的关系,并得出光束偏移是引起标度因数随温度周期性变化的原因。根据标度因数与稳频电压的关系,建立了全反射棱镜式激光陀螺标度因数补偿模型,通过实验对比了补偿前后标度因数的非线性度。结果表明,根据该补偿模型对全反射棱镜式激光陀螺标度因数进行补偿,标度因数非线性度提高了一个数量级以上,对提高全反射棱镜式激光陀螺的性能具有一定的参考价值。  相似文献   

4.
结出了双重Q^2重标度模型的重标度参数经验公式,其中建立了重标度参数ξV,ξS及ξG与原子核平均结合能之间的联系,利用这套公式可以给出A≥12的所有核的重标度参数值,进而可以采用这些重标度参数值计算有关核过程做出预言。  相似文献   

5.
给出了双重Q2 重标度模型的重标度参数经验公式 ,其中建立了重标度参数 ξV,ξS 及 ξG 与原子核平均结合能之间的联系 .利用这套公式可以给出A≥ 1 2的所有核的重标度参数值 ,进而可以采用这些重标度参数值计算有关核过程做出预言 .  相似文献   

6.
唐刚  马本堃 《物理学报》2001,50(5):851-855
使用动力学重整化群和直接标度分析的方法研究了非局域Lai-Das Sarma-Villain方程的动力学标度性质.动力学重整化群分析表明非局域非线性项的存在能够导致新的固定点和连续变化的动力学标度指数的产生.使用直接标度分析方法则分别得到了在弱耦合和强耦合区内的标度指数值.在弱耦合区域内得到的标度指数与动力学重整化方法得到的标度指数值能很好地吻合. 关键词: 表面生长 动力学重整化群分析 标度分析  相似文献   

7.
胡岗 《物理学报》1985,34(5):573-580
本文用格林函数方法讨论Fokker-Planck方程的非定态问题,将标度理论的“标度区”和“最终时区”统一考虑。在标度理论的头两个时区,所得结果与标度理论的解一致。当t→∞时,所得的非定态解趋于Fokker-Planck方程的定态解,解决了标度区分布函数在稳定点发散的问题,避免了“标度区”和“最终时区”对接的困难。 关键词:  相似文献   

8.
给出了推广x重新标度模型的重标度参数经验公式,其中建立了重标度参数与原子核的平均结合能之间的联系,由该公式可以得出A≥12的所有核的重标度参数值,利用这些参数值可以计算有关核过程并做出预言.  相似文献   

9.
唐刚  马本堃 《物理学报》2002,51(5):994-998
将直接标度分析方法推广应用到含时间空间关联噪声的非局域及各向异性KardarParisiZhang方程的动力学标度分析中,分别得到了方程在强耦合区和弱耦合区的标度指数值.在弱耦合区得到的标度指数能与使用动力学重整化方法得到的结果相吻合 关键词: 表面生长 标度分析 KPZ方程  相似文献   

10.
给出了双重Q2重标度模型的重标度参数经验公式,其中建立了重标度参数ξVS及ξG与原子核平均结合能之间的联系.利用这套公式可以给出A≥12的所有核的重标度参数值,进而可以采用这些重标度参数值计算有关核过程做出预言.  相似文献   

11.
In the present paper we discuss the critical behavior of Thornsystem using Catastrophe Theory. The universal critical asymptotic form of the family of free energy functions for Thomsystem with one order parameter and two field parameters is obtained. The expressions of critical exponents, the scaling laws, and the scaling hypotheses are all derived from this universal asymptotic form.  相似文献   

12.
13.
Previous numerical studies have revealed the existence of embedded solitons (ESs) in a class of multiwave systems with quadratic nonlinearity, families of which seem to emerge from a critical point in the parameter space, where the zero solution has a fourfold zero eigenvalue. In this paper, the existence of such solutions is studied in a three-wave model. An appropriate rescaling casts the system in a normal form, which is universal for models supporting ESs through quadratic nonlinearities. The normal-form system contains a single irreducible parameter epsilon, and is tantamount to the basic model of type-I second-harmonic generation. An analytical approximation of Wentzel-Kramers-Brillouin type yields an asymptotic formula for the distribution of discrete values of epsilon at which the ESs exist. Comparison with numerical results shows that the asymptotic formula yields an exact value of the scaling index, -65, and a fairly good approximation for the numerical factor in front of the scaling term.  相似文献   

14.
《Physica A》1991,179(3):344-377
The paper is concerned with some theoretical and empirical attempts to obtain a unified equation for the thermodynamic properties of fluids that incorporates the nonclassical scaling laws near the critical point and crosses over to a classical analytic equation far away from the critical point. Specifically we investigate to what extent the various proposed crossover models agree with the known theoretical predictions for the universal ratios among the asymptotic and correction-to-scaling amplitudes in the power-law expansions of the thermodynamic properties around the critical point.  相似文献   

15.
Critical dynamics in film geometry is analyzed within the field-theoretical approach. In particular we consider the case of purely relaxational dynamics (Model A) and Dirichlet boundary conditions, corresponding to the so-called ordinary surface universality class on both confining boundaries. The general scaling properties for the linear response and correlation functions and for dynamic Casimir forces are discussed. Within the Gaussian approximation we determine the analytic expressions for the associated universal scaling functions and study quantitatively in detail their qualitative features as well as their various limiting behaviors close to the bulk critical point. In addition we consider the effects of time-dependent fields on the fluctuation-induced dynamic Casimir force and determine analytically the corresponding universal scaling functions and their asymptotic behaviors for two specific instances of instantaneous perturbations. The universal aspects of nonlinear relaxation from an initially ordered state are also discussed emphasizing the different crossovers occurring during this evolution. The model considered is relevant to the critical dynamics of actual uniaxial ferromagnetic films with symmetry-preserving conditions at the confining surfaces and for Monte Carlo simulations of spin system with Glauber dynamics and free boundary conditions.  相似文献   

16.
非平衡相变的临界标度理论及普适性   总被引:10,自引:0,他引:10  
综述了作者近年来在非平衡相变临界( N P C) 标度理论及普适性研究的进展。主要包括一般 N P C 系统规格化模型,局域序参量的概率分布,广义势的临界渐近形式,空时有关函数及其临界奇异行为。论证了 N P C 系统的临界可标度性,导出了一组普适的 N P C 标度关系,由之计算出的4 种 N P C 普适类的临界指数与目前已知的实验及理论结果吻合得非常好。此外,还讨论了非平衡相变临界标度理论的普适性,将平衡相变临界标度理论作为一种特殊极限情况含于同一理论体系中。  相似文献   

17.
综述了作者近年来在非平衡相变临界( N P C) 标度理论及普适性研究的进展。主要包括一般 N P C 系统规格化模型,局域序参量的概率分布,广义势的临界渐近形式,空时有关函数及其临界奇异行为。论证了 N P C 系统的临界可标度性,导出了一组普适的 N P C 标度关系,由之计算出的4 种 N P C 普适类的临界指数与目前已知的实验及理论结果吻合得非常好。此外,还讨论了非平衡相变临界标度理论的普适性,将平衡相变临界标度理论作为一种特殊极限情况含于同一理论体系中。  相似文献   

18.
The probability distribution of the order parameter is expected to take a universal scaling form at a phase transition. In a spin system at a quantum critical point, this corresponds to universal statistics in the distribution of the total magnetization in the low-lying states. We obtain this scaling function exactly for the ground state and first excited state of the critical quantum Ising spin chain. This is achieved through a remarkable relation to the partition function of the anisotropic Kondo problem, which can be computed by exploiting the integrability of the system.  相似文献   

19.
Analytic maps of the form \(f(z) = e^{2\pi i\Omega } z + \mathcal{O}(z^2 )\) display quasiperiodicity when Ω satisfies a diophantine condition. Quasiperiodic motion is confined to a neighborhood of the origin known as a Siegel domain. The boundary of this domain obeys universal scaling relations. In this paper we investigate these scaling relations through a renormalization group analysis, and we discuss singularities and asymptotic form of the scaling function.  相似文献   

20.
We consider the universality class of the two-dimensional tricritical Ising model. The scaling form of the free energy leads to the definition of universal ratios of critical amplitudes which may have experimental relevance. We compute these universal ratios by a combined use of results coming from perturbed conformal field theory, integrable quantum field theory, and numerical methods.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号